| 2016 |
| "Magnetic susceptibility of actinide(III) cations: an experimental and theoretical study" Autillo M, Guerin L, Bolvin H, Moisy P and Berthon C , PHYSICAL CHEMISTRY CHEMICAL PHYSICS., MAR 7, {2016}. Vol. {18}({9}), pp. {6515-6525}. (2016}. |
| Abstract: In a previous paper, the influence of radioactive decay (alpha and beta(-)) on magnetic susceptibility measurements by the Evans method has been demonstrated by the study of two americium isotopes. To characterize more accurately this phenomenon and particularly its influence on the Curie law, a new study has been performed on two uranium isotopes (U-238 and U-233) and on tritiated water ((H2O)-H-3). The results on the influence of alpha emissions have established a relationship between changes in the temperature dependence and the radioactivity in solution. Regarding the beta(-) emissions, less influence was observed while no temperature dependence linked to this kind of radioactive emission could be identified. Once magnetic susceptibility measurements of actinide(III) cations were corrected from radioactivity effects, methods of quantum chemistry have been used on free ions and aquo complexes to calculate the electronic structure explaining the magnetic properties of Pu(III), Am(III) and Cm(III). The ligand field effect on the magnetic behavior (the Curie constant and temperature-independent susceptibilities) was analyzed by considering different solvation environments. |
BibTeX:
@article{ISI:000371139400017,
author = {Autillo, Matthieu and Guerin, Laetitia and Bolvin, Helene and Moisy, Philippe and Berthon, Claude},
title = {Magnetic susceptibility of actinide(III) cations: an experimental and theoretical study},
journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},
year = {2016},
volume = {18},
number = {9},
pages = {6515-6525},
doi = {10.1039/c5cp07456h}
}
|
| "Radiation chemical behavior of aqueous butanal oxime solutions irradiated with helium ion beams" Costagliola A, Venault L, Deroche A, Garaix G, Vermeulen J, Omnee R, Duval F, Blain G, Vandenborre J, Fattahi-Vanani M and Vigier N, RADIATION PHYSICS AND CHEMISTRY., FEB, {2016}. Vol. {119}, pp. {186-193}. (2016). |
| Abstract: Samples of butanal oxime in aqueous solution have been irradiated with the helion (He-4(2+)) beam of the ARRONAX (Nantes) and the CEMHTI (Orleans) cyclotrons. The consumption yield of butanal oxime has been measured by gas-chromatography coupled with mass spectrometry. Yields of gaseous products (mainly H-2) have also been measured by micro-gas-chromatography. Butanal oxime can react with H-center dot radicals by abstraction mechanism to enhance H-2 production. Yields of liquid phase products (hydrogen peroxide and nitrite ion) have been measured by colorimetric methods. Butanal oxime acts as a scavenger of OH center dot radical to inhibit the production of H2O2. The observation of the radiolytic products allows then to discuss a degradation mechanism of butanal oxime in aqueous solutions. (C) 2015 Published by Elsevier Ltd. |
BibTeX:
@article{ISI:000367282200027,
author = {Costagliola, A. and Venault, L. and Deroche, A. and Garaix, G. and Vermeulen, J. and Omnee, R. and Duval, F. and Blain, G. and Vandenborre, J. and Fattahi-Vanani, M. and Vigier, N.},
title = {Radiation chemical behavior of aqueous butanal oxime solutions irradiated with helium ion beams},
journal = {RADIATION PHYSICS AND CHEMISTRY},
year = {2016},
volume = {119},
pages = {186-193},
doi = {10.1016/j.radphyschem.2015.10.010}
}
|
| "Decay Mechanism of NO3 center dot Radical in Highly Concentrated Nitrate and Nitric Acidic Solutions in the Absence and Presence of Hydrazine" Garaix G, Horne GP, Venault L, Moisy P, Pimblott SM, Marignier J-L and Mostafavi M, JOURNAL OF PHYSICAL CHEMISTRY B., JUN 9, {2016}. Vol. {120}({22}), pp. {5008-5014}. (2016). |
| Abstract: The decay mechanism of NO3 center dot has been determined through a combination of experiment and calculation for 7 mol dm(-3) solutions of deaerated aqueous LiNO3 and HNO3, in the absence and presence of hydrazine (N2H4, N2H5+, and N-2,H-6(2+)). In the absence of hydrazine, the predominant NO3 center dot decay pathways are strongly dependent upon the pH of the solution. For neat, neutral pH LiNO3 solutions (7 mol dm 3), NO3 center dot produced by the pulse is fully consumed within 160 mu s by OH center dot (37, H2O (29, NO2- (17, and NO2 (17. For acidic HNO3 solutions (7 mol dm-3), radiolytically produced NO3 center dot is predominantly consumed within 1 ms by HNO2 (15 and NO2 (80. Intervening formulations exhibit the mechanistic transition from neat LiNO3 to neat HNO3. In highly acidic nitric acid solution, hydrazine exists mainly as N2H5+ and N2H62+, both of which rapidly consume NO3 center dot in addition to other decay mechanisms, with rate constants of 2.9 (+/- 0.9) X 10(7) and 1.3 (+/- 0.3) X 10(6) dm(3) mol(-1) s(-1), respectively. |
BibTeX:
@article{ISI:000377841200015,
author = {Garaix, Guillaume and Horne, Gregory P. and Venault, Laurent and Moisy, Philippe and Pimblott, Simon M. and Marignier, Jean-Louis and Mostafavi, Mehran},
title = {Decay Mechanism of NO3 center dot Radical in Highly Concentrated Nitrate and Nitric Acidic Solutions in the Absence and Presence of Hydrazine},
journal = {JOURNAL OF PHYSICAL CHEMISTRY B},
year = {2016},
volume = {120},
number = {22},
pages = {5008-5014},
doi = {10.1021/acs.jpcb.6b02915}
}
|
| "Reaction Mechanisms in Talc under Ionizing Radiation: Evidence of a High Stability of H-center dot Atoms" Laine M, Allard T, Balan E, Martin F, Von Bardeleben HJ, Robert J-L and Le Caer S ({2016}), JOURNAL OF PHYSICAL CHEMISTRY C, FEB, Vol. {120}({4}), pp. {2087-2095}. 2016. |
| Abstract: The reactivity under ionizing radiation of synthetic and natural talc was studied. The two samples were chosen as models of nonswelling clays. H-2 production measurements evidenced that the H-2 yield in synthetic talc was of the same order of magnitude as in water, implying a very efficient production, and then recombination, of hydrogen atoms arising from the lysis of structural -OH groups. This yield was 30 times smaller in natural talc. The discrepancy between synthetic and natural talc is most likely related to transition elements cationic impurities in the latter. Even if they are present in very small amounts, they are able to efficiently scavenge the electrons and/or the hydrogen atoms. The produced defects in irradiated synthetic talc were investigated by means of electron paramagnetic resonance (EPR) spectroscopy, which enabled proposing reaction mechanisms. Lastly, the EPR spectra evidenced the presence, at 298 K, of hydrogen atoms, which were detected few days after irradiation in both types of talc. This surprisingly high stability was mainly attributed to the absence of water molecules. It is proposed that the hydrogen atoms are stabilized in octahedra between two tetraedra sheets. |
BibTeX:
@article{ISI:000369772900009,
author = {Laine, Maxime and Allard, Thierry and Balan, Etienne and Martin, Francois and Von Bardeleben, H. Jurgen and Robert, Jean-Louis and Le Caer, Sophie},
title = {Reaction Mechanisms in Talc under Ionizing Radiation: Evidence of a High Stability of H-center dot Atoms},
journal = {JOURNAL OF PHYSICAL CHEMISTRY C},
year = {2016},
volume = {120},
number = {4},
pages = {2087-2095},
doi = {10.1021/acs.jpcc.5b11396}
}
|
| "Ultrafast Decay of the Solvated Electron in a Neat Polar Solvent: The Unusual Case of Propylene Carbonate" Le Caer S, Ortiz D, Marignier J-L, Schmidhammer U, Belloni J and Mostafavi M , JOURNAL OF PHYSICAL CHEMISTRY LETTERS., JAN 7, {2016}. Vol. {7}({1}), pp. {186-190}. (2016). |
| Abstract: The behavior of carbonates is critical for a detailed understanding of aging phenomena in Li-ion batteries. Here we study the first reaction stages of propylene carbonate (PC), a cyclical carbonate, by picosecond pulse radiolysis. An absorption band with a maximum around 1360 nm is observed at 20 ps after the electron pulse and is shifted to 1310 nm after 50 ps. This band presents the features of a solvated electron absorption band, the solvation lasting up to 50 ps. Surprisingly, in this polar solvent, the solvated electron follows an ultrafast decay and disappears with a half time of 360 ps. This is attributed to the formation of a radical anion PC-center dot. The yield of the solvated electron is low, suggesting that the radical anions are mainly directly produced from presolvated electrons. These results demonstrate that the initial electron transfers mechanisms are strongly different in linear compared with cyclical carbonates. |
BibTeX:
@article{ISI:000367968700032,
author = {Le Caer, Sophie and Ortiz, Daniel and Marignier, Jean-Louis and Schmidhammer, Uli and Belloni, Jacqueline and Mostafavi, Mehran},
title = {Ultrafast Decay of the Solvated Electron in a Neat Polar Solvent: The Unusual Case of Propylene Carbonate},
journal = {JOURNAL OF PHYSICAL CHEMISTRY LETTERS},
year = {2016},
volume = {7},
number = {1},
pages = {186-190},
doi = {10.1021/acs.jpclett.5b02668}
}
|
| "Identification of Transient Radical Anions (LiClO4)(n)(-) (n=1-3) in THF Solutions: Experimental and Theoretical Investigation on Electron Localization in Oligomers" Ma J, Archirel P, Pernot P, Schmidhammer U, Le Caer S and Mostafavi M, JOURNAL OF PHYSICAL CHEMISTRY B., FEB 4, {2016}. Vol. {120}({4}), pp. {773-784}. (2016). |
| Abstract: Picosecond pulse radiolysis measurements of tetrahydrofuran (THF) solutions containing LiClO4 over a wide range of concentration are performed to investigate the formation of transient species. The Cl-35 NMR measurements of these solutions prior to irradiation show that the salt is in the form of (LiClO4)(n) oligomers. Kinetics and transient absorption spectra of intermediates in each solution are obtained on the time scale from 10 to 3800 ps. A global spectro-kinetic matrix of the data is analyzed by the multicurve resolution alternated least-squares (MCR-ALS) method. It shows the presence of 3 transient species induced by electron pulse, in addition to the solvated electron. A hybrid Monte Carlo/DFT molecular simulation method is elaborated, using the MPW1K functional for the configuration sampling and B3LYP for the spectra calculations. The maximum of the absorption band of the monomer (LiClO4)(-), dimer (LiClO4)(2)(-), trimer (LiClO4)(3)(-), and tetramer (LiClO4)(4)(-) anions are deduced from the simulations. They enable one to label the MCR-ALS spectra (differences are below 0.1 eV) and to interpret the kinetic data. The simulations show also that Li-1 ion catalyzes the reduction of perchlorate by excess electrons. Only the dimer anion, due to its unique structure with a stable Li-2(+) core and two nonbridging perchlorates, presents higher stability toward ClO4- reduction into ClO3-. It corresponds to the long-lived species observed in the experiments. |
BibTeX:
@article{ISI:000369773100019,
author = {Ma, Jun and Archirel, Pierre and Pernot, Pascal and Schmidhammer, Uli and Le Caer, Sophie and Mostafavi, Mehran},
title = {Identification of Transient Radical Anions (LiClO4)(n)(-) (n=1-3) in THF Solutions: Experimental and Theoretical Investigation on Electron Localization in Oligomers},
journal = {JOURNAL OF PHYSICAL CHEMISTRY B},
year = {2016},
volume = {120},
number = {4},
pages = {773-784},
doi = {10.1021/acs.jpcb.5b11315}
}
|
| "Ostwald ripening in a yield-stress fluid under uniform gas production" Marchal A, Vergnes B, Poulesquen A and Valette R, JOURNAL OF NON-NEWTONIAN FLUID MECHANICS., MAY, {2016}. Vol. {231}, pp. {49-55}. (2016). |
| Abstract: The evolution kinetics of a bubble population driven by a uniform production of gas in a yield-stress fluid matrix is investigated in the context of the long time swelling of bitumen drums in which radioactive salts have been dispersed (salts suspensions in a bitumen matrix). Radioactivity generates uniform volume production of hydrogen by radiolysis of bitumen chains. Since the production rate of gas occurs on very long time scales (more than a hundred years), one needs to set up theoretical models to predict the material swelling. It has been shown in previous studies that bitumen is a yield stress fluid. Therefore, the present work proposes to study the influence of a yield stress and of the production rate of gas on the evolution kinetics of a bubbles population. Usually, in a non-yield stress fluid and without gas creation, a supersaturation of gas leads to a scenario of germination, bubble growth and Ostwald ripening (growth of large bubbles at the expense of smaller ones). Over long times, a self-similar distribution of large bubbles is selected, independent of the initial distribution of nuclei. In this work, it is shown that there exist conditions for which the yield stress competes with the kinetics of ripening and induces hysteresis phenomena on the kinetics of bubbles distribution. The coupled effect of gas production rate and yield stress on the final population is discussed. (C) 2016 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000375500100005,
author = {Marchal, A. and Vergnes, B. and Poulesquen, A. and Valette, R.},
title = {Ostwald ripening in a yield-stress fluid under uniform gas production},
journal = {JOURNAL OF NON-NEWTONIAN FLUID MECHANICS},
year = {2016},
volume = {231},
pages = {49-55},
doi = {10.1016/j.jnnfm.2016.03.005}
}
|
| "Picosecond Pulse Radiolysis of Propylene Carbonate as a Solute in Water and as a Solvent" Marignier J-L, Torche F, Le Caer S, Mostafavi M and Belloni J, JOURNAL OF PHYSICAL CHEMISTRY B., MAR 10, {2016}. Vol. {120}({9}), pp. {2388-2396}. (2016). |
| Abstract: The ester propylene carbonate (PC) is a solvent with a high static dielectric constant where the charges generated by ionizing radiation are expected to be long-lived at room temperature. Time-resolved optical absorption spectroscopy after picosecond electron pulses reveals the formation of a UV band, within less than two nanoseconds, that is assigned to the radical anion PC-center dot, arising from a fast attachment reaction of electrons onto PC. Assignment and reactivity of PC-center dot in neat solvent and solutions are discussed in relation with data obtained in solutions of PC in water under reducing or oxidizing conditions and in solutions in PC of aromatic scavengers with various reduction potentials. The fate of the electrons and the ionization yield in PC are compared with those of other solvents. |
BibTeX:
@article{ISI:000372042000035,
author = {Marignier, Jean-Louis and Torche, Faycal and Le Caer, Sophie and Mostafavi, Mehran and Belloni, Jacqueline},
title = {Picosecond Pulse Radiolysis of Propylene Carbonate as a Solute in Water and as a Solvent},
journal = {JOURNAL OF PHYSICAL CHEMISTRY B},
year = {2016},
volume = {120},
number = {9},
pages = {2388-2396},
doi = {10.1021/acs.jpcb.5b11793}
}
|
| "Impact of radiolysis and radiolytic corrosion on the release of C-13 and Cl-37 implanted into nuclear graphite: Consequences for the behaviour of C-14 and Cl-36 in gas cooled graphite moderated reactors" Moncoffre N, Toulhoat N, Bererd N, Pipon Y, Silbermann G, Blondel A, Galy N, Sainsot P, Rouzaud JN, Deldicque D and Dauvois V, JOURNAL OF NUCLEAR MATERIALS., APR 15, {2016}. Vol. {472}, pp. {252-258}. (2016). |
| Abstract: Graphite finds widespread use in many areas of nuclear technology based on its excellent moderator and reflector qualities as well as its strength and high temperature stability. Thus, it has been used as moderator or reflector in CO2 cooled nuclear reactors such as UNGG, MAGNOX, and AGR. However, neutron irradiation of graphite results in the production of C-14 (dose determining radionuclide) and Cl-36 (long lived radionuclide), these radionuclides being a key issue regarding the management of the irradiated waste. Whatever the management option (purification, storage, and geological disposal), a previous assessment of the radioactive inventory and the radionuclide's location and speciation has to be made. During reactor operation, the effects of radiolysis are likely to promote the radionuclide release especially at the gas/graphite interface. Radiolysis of the coolant is mainly initiated through gamma irradiation as well as through Compton electrons in the graphite pores. Radiolysis can be simulated in laboratory using gamma irradiation or ion irradiation. In this paper, C-13, Cl-37 and N-14 are implanted into virgin nuclear graphite in order to simulate respectively the presence of C-14, Cl-36 and nitrogen, a C-14 precursor. Different irradiation experiments were carried out using different irradiation devices on implanted graphite brought into contact with a gas simulating the coolant. The aim was to assess the effects of gas radiolysis and radiolytic corrosion induced by gamma or He2+ irradiation at the gas/graphite interface in order to evaluate their role on the radionuclide release. Our results allow inferring that radiolytic corrosion has clearly promoted the release of C-14, Cl-36 and N-14 located at the graphite brick/gas interfaces and open pores. (C) 2016 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000373489700031,
author = {Moncoffre, N. and Toulhoat, N. and Bererd, N. and Pipon, Y. and Silbermann, G. and Blondel, A. and Galy, N. and Sainsot, P. and Rouzaud, J. -N. and Deldicque, D. and Dauvois, V.},
title = {Impact of radiolysis and radiolytic corrosion on the release of C-13 and Cl-37 implanted into nuclear graphite: Consequences for the behaviour of C-14 and Cl-36 in gas cooled graphite moderated reactors},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2016},
volume = {472},
pages = {252-258},
doi = {10.1016/j.jnucmat.2015.12.020}
}
|
| "Oxidative dissolution of unirradiated Mimas MOX fuel (U/Pu oxides) in carbonated water under oxic and anoxic conditions" Odorowski M, Jegou C, De Windt L, Broudic V, Peuget S, Magnin M, Tribet M and Martin C, JOURNAL OF NUCLEAR MATERIALS., JAN, {2016}. Vol. {468}, pp. {17-25}. (2016). |
| Abstract: Few studies exist concerning the alteration of Mimas Mixed-OXide (MOX) fuel, a mixed plutonium and uranium oxide, and data is needed to better understand its behavior under leaching, especially for radioactive waste disposal. In this study, two leaching experiments were conducted on unirradiated MOX fuel with a strong alpha activity (13 x 10(9) Bq.g(MOX)(-1) reproducing the alpha activity of spent MOX fuel with a burnup of 47 GWd.t(HM)(-1) after 60 years of decay), one under air (oxic conditions) for 5 months and the other under argon (anoxic conditions with [O-2] < 1 ppm) for one year in carbonated water (10(-2) mol L-1). For each experiment, solution samples were taken over time and Eh and pH were monitored. The uranium in solution was assayed using a kinetic phosphorescence analyzer (ICPA), plutonium and americium were analyzed by a radiochemical route, and H2O2 generated by the water radiolysis was quantified by chemiluminescence. Surface characterizations were performed before and after leaching using Scanning Electron Microscopy (SEM), Electron Probe Microanalyzer (EPMA) and Raman spectroscopy. Solubility diagrams were calculated to support data discussion. The uranium releases from MOX pellets under both oxic and anoxic conditions were similar, demonstrating the predominant effect of alpha radiolysis on the oxidative dissolution of the pellets. The uranium released was found to be mostly in solution as carbonate species according to modeling, whereas the Am and Pu released were significantly sorbed or precipitated onto the TiO2 reactor. An intermediate fraction of Am (12 was also present as colloids. SEM and EPMA results indicated a preferential dissolution of the UO2 matrix compared to the Pu-enriched agglomerates, and Raman spectroscopy showed the Pu-enriched agglomerates were slightly oxidized during leaching. Unlike Pu-enriched zones, the UO2 grains were much more sensitive to oxidative dissolution, but the presence of carbonates did not enable observation of an oxidized layer by Raman spectroscopy with the exception of a few areas revealing the presence of U4O9. This data shows the heterogeneous nature of the alteration and the need to combine information from different techniques to determine the origin of releases. (C) 2015 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000367761700003,
author = {Odorowski, Melina and Jegou, Christophe and De Windt, Laurent and Broudic, Veronique and Peuget, Sylvain and Magnin, Magali and Tribet, Magaly and Martin, Christelle},
title = {Oxidative dissolution of unirradiated Mimas MOX fuel (U/Pu oxides) in carbonated water under oxic and anoxic conditions},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2016},
volume = {468},
pages = {17-25},
doi = {10.1016/j.jnucmat.2015.09.059}
}
|
| "Photoreduction of the ferredoxin/ferredoxin-NADP(+)-reductase complex by a linked ruthenium polypyridyl chromophore" Quaranta A, Lagoutte B, Frey J and Setif P, JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY., JUL, {2016}. Vol. {160}, pp. {347-354}. (2016). |
| Abstract: Photosynthetic ferredoxin and its main partner ferredoxin-NADP-reductase (FNR) are key proteins during the photoproduction of reductive power involved in photosynthetic growth. In this work, we used covalent attachment of ruthenium derivatives to different cysteine mutants of ferredoxin to trigger by laser-flash excitation both ferredoxin reduction and subsequent electron transfer from reduced ferredoxin to FNR. Rates and yields of reduction of the ferredoxin [2Fe-2S] cluster by reductively quenched Ru* could be measured for the first time for such a low redox potential protein whereas ferredoxin-FNR electron transfer was characterized in detail for one particular Ru-ferredoxin covalent adduct. For this adduct, the efficiency of FNR single reduction by reduced ferredoxin was close to 100% under both first-order and diffusion-limited second-order conditions. Interprotein intracomplex electron transfer was measured unambiguously for the first time with a fast rate of c. 6500 s(-1). Our measurements point out that Ru photosensitizing is a powerful approach to study the functional interactions of ferredoxin with its numerous partners besides FNR. (C) 2016 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000378453500040,
author = {Quaranta, Annamaria and Lagoutte, Bernard and Frey, Julien and Setif, Pierre},
title = {Photoreduction of the ferredoxin/ferredoxin-NADP(+)-reductase complex by a linked ruthenium polypyridyl chromophore},
journal = {JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY},
year = {2016},
volume = {160},
pages = {347-354},
doi = {10.1016/j.jphotobiol.2016.04.030}
}
|
| 2015 |
| "Water radiolysis with heavy-ion beams at GANIL. Back to 20 years of investigations." Baldacchino G, In CIRIL, 30 YEARS OF INTERDISCIPLINARY RESEARCH AT GANIL. Vol. {629}, (2015). |
| Abstract: This article reports a short history of the studies carried out in the domain of radiation chemistry with the swift heavy ions of GANIL (Grand Accelerateur National d'Ions Lourds) during the last 20 years. The originality of these studies lays on two main aspects which were never been investigated simultaneously before: 1) the energy of the GANIL ions provides an energy deposition in small samples (few millimeters) that can be considered as almost constant; this allows studies on LET-effect on radiolytic yields, 2) production of pulses as short as a few nanoseconds made available the access to pulse radiolysis method and the study of transient chemical species such as hydrated electron, hydroxyl radical and superoxide. Future is now focus on high temperature effects on water radiolysis for which, again, nothing exist but only simulations and speculations. |
BibTeX:
@inproceedings{ISI:000359790700009,
author = {Baldacchino, G.},
title = {Water radiolysis with heavy-ion beams at GANIL. Back to 20 years of investigations.},
booktitle = {CIRIL, 30 YEARS OF INTERDISCIPLINARY RESEARCH AT GANIL},
year = {2015},
volume = {629},
note = {Conference on CIRIL - More Than 30 Years of Interdisciplinary Research at GANIL Meeting, Caen, FRANCE, OCT 17, 2013},
doi = {10.1088/1742-6596/629/1/012009}
}
|
| "RADIOLYSIS OF NITROGEN AND WATER-ICE MIXTURE BY FAST IONS: IMPLICATIONS FOR KUIPER BELT OBJECTS" de Barros ALF, da Silveira EF, Bergantini A, Rothard H and Boduch P, ASTROPHYSICAL JOURNAL., SEP 10, {2015}. Vol. {810}({2}), (2015). |
| Abstract: The participation of condensed nitrogen in the surface chemistry of some objects in the outer solar system, such as Pluto and Triton, is very important. The remote observation of this species using absorption spectroscopy is a difficult task because N-2 is not IR active in the gas phase. Water is also among the most abundant molecules in the surface of these objects; chemical reactions between N-2 and H2O induced by cosmic rays are therefore expected. Although pure N-2 ice is hardly identified by IR spectroscopy, the species produced through the processing of the surface ice by cosmic rays may give relevant clues indicating how abundant the N-2 is in the outside layers of the surface of trans-Neptunian objects (TNOs). The objective of this work is to investigate the formation of nitrogenated species induced by cosmic-ray analogs in an ice mixture containing nitrogen and water. Experiments were performed in the GANIL Laboratory by bombarding N-2:H2O (10:1) ice at 15 K with 40 MeV Ni-58(11+) ions. Evolution of precursor and daughter species was monitored by Fourier transform infrared spectrometry. The main produced species are the nitrogen oxides NOk (k = 1-3), N2Oj (j = 1-5), N-3, and O-3. Among them, the N2O and N-3 are the most abundant, representing similar to 61% of the total column density of the daughter molecules at 10(13) ions cm(-2) fluence; the current results indicate that the yield of daughter species from this mixture is low, and this may be one of the reasons why NiOj molecules are not usually observed in TNOs. |
BibTeX:
@article{ISI:000362083700072,
author = {de Barros, A. L. F. and da Silveira, E. F. and Bergantini, A. and Rothard, H. and Boduch, P.},
title = {RADIOLYSIS OF NITROGEN AND WATER-ICE MIXTURE BY FAST IONS: IMPLICATIONS FOR KUIPER BELT OBJECTS},
journal = {ASTROPHYSICAL JOURNAL},
year = {2015},
volume = {810},
number = {2},
doi = {10.1088/0004-637X/810/2/156}
}
|
| "Evaluation of the feasibility of the powder injection moulding process for the fabrication of nuclear fuel and comparison of several formulations" Bricout J, Matheron P, Ablitzer C, Gelin JC, Brothier M and Barriere T, POWDER TECHNOLOGY., JUL, {2015}. Vol. {279}, pp. {49-60}. (2015). |
| Abstract: Six forming aid formulations were used to assess the nuclear fuel elaboration by means of the powder injection moulding (NM) process. These formulations were especially designed for actinide powders (UO2 and MOX) by taking into account the specificities of these powders, in particular any solutions to prevent radiolysis. Once the feedstocks with the UO2 powder had been prepared, the thermal studies showed no significant endothermic or exothermic reaction, which demonstrates the quasi-independent behaviour of the polymer system with respect to the uranium dioxide powder. The mass of the carbon residues a key criterion in selecting a formulation was below 150 ppm for all six formulations, which is still sufficient for obtaining net-shaped pellets following the sintering process. The formulations to be recommended for the nuclear fuel application are those containing polystyrene as they achieve satisfactory deagglomeration combined with an adequate level of injectability (low shear viscosity of the system). Moreover, they are theoretically resistant to radiolysis phenomena due to the benzene rings of the polystyrene. (C) 2015 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000356123400008,
author = {Bricout, J. and Matheron, P. and Ablitzer, C. and Gelin, J. C. and Brothier, M. and Barriere, Th},
title = {Evaluation of the feasibility of the powder injection moulding process for the fabrication of nuclear fuel and comparison of several formulations},
journal = {POWDER TECHNOLOGY},
year = {2015},
volume = {279},
pages = {49-60},
doi = {10.1016/j.powtec.2015.03.038}
}
|
| "Anion emission from water molecules colliding with positive ions: Identification of binary and many-body processes" Chesnel JY, Juhasz Z, Lattouf E, Tanis JA, Huber BA, Bene E, Kovacs STS, Herczku P, Mery A, Poully JC, Rangama J and Sulik B, PHYSICAL REVIEW A., JUN 29, {2015}. Vol. {91}({6}). (2015). |
| Abstract: It is shown that negative ions are ejected from gas-phase water molecules when bombarded with positive ions at keV energies typical of solar-wind velocities. This finding is relevant for studies of planetary and cometary atmospheres, as well as for radiolysis and radiobiology. Emission of both H- and heavier (O- and OH-) anions, with a larger yield for H-, was observed in 6.6-keV(16)O(+) + H2O collisions. The experimental setup allowed separate identification of anions formed in collisions with many-body dynamics from those created in hard, binary collisions. Most of the anions are emitted with low kinetic energy due to many-body processes. Model calculations show that both nucleus-nucleus interactions and electronic excitations contribute to the observed large anion emission yield. |
BibTeX:
@article{ISI:000357020000001,
author = {Chesnel, J. -Y. and Juhasz, Z. and Lattouf, E. and Tanis, J. A. and Huber, B. A. and Bene, E. and Kovacs, S. T. S. and Herczku, P. and Mery, A. and Poully, J. -C. and Rangama, J. and Sulik, B.},
title = {Anion emission from water molecules colliding with positive ions: Identification of binary and many-body processes},
journal = {PHYSICAL REVIEW A},
year = {2015},
volume = {91},
number = {6},
doi = {10.1103/PhysRevA.91.060701}
}
|
| "Effect of gamma irradiation on MnO2/Ag2O hydrogen getter" Chlique C, Lambertin D, Galliez K, Labed V, Dannoux-Papin A, Jobic S, Deniard P and Leoni E, JOURNAL OF NUCLEAR MATERIALS., MAR, {2015}. Vol. {458}, pp. {162-167}. (2015). |
| Abstract: This study aims to show the stability of c-MnO2/Ag2O hydrogen getter under gamma irradiation in order to be suitable for decreasing the hydrogen risk during the nuclear waste transportation. The chemical and the structural properties of the getter were barely unchanged for irradiated doses up to 4 MGy. The pair distribution function (PDF) analysis showed that the c-MnO2, which can be describe as an intergrowth of the ramsdellite phase (R-MnO2) and the pyrolusite phase (beta-MnO2), had the same intergrowth rate (around 60% for beta-MnO2 and 40% for R-MnO2) after irradiation and the silver containing promoter was also unchanged. The getter remains therefore efficient for hydrogen trapping. Furthermore, c-MnO2/Ag2O was tested in a closed environment in the presence of hydrogen released by organic technological waste radiolysis, such as polyvinyl chloride, ion exchange resins, polyethylene and silicone. Over 80% of the hydrogen, generated by organic radiolysis, was trapped under a 1.5 MGy gamma irradiation. (C) 2014 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000349169600019,
author = {Chlique, Christophe and Lambertin, David and Galliez, Kevin and Labed, Veronique and Dannoux-Papin, Adeline and Jobic, Stephane and Deniard, Philippe and Leoni, Elisa},
title = {Effect of gamma irradiation on MnO2/Ag2O hydrogen getter},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2015},
volume = {458},
pages = {162-167},
doi = {10.1016/j.jnucmat.2014.11.128}
}
|
| "Swift heavy ion modifications of astrophysical water ice" Dartois E, Auge B, Rothard H, Boduch P, Brunetto R, Chabot M, Domaracka A, Ding JJ, Kamalou O, Lv XY, Frota da Silveira E, Thomas JC, Pino T, Mejia C, Godard M and de Barros ALF, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS., DEC 15, {2015}. Vol. {365}({B}), pp. {472-476}. (2015). |
| Abstract: In the relatively shielded environments provided by interstellar dense clouds in our Galaxy, infrared astronomical observations have early revealed the presence of low temperature (10-100 K) ice mantles covering tiny grain ``cores'' composed of more refractory material. These ices are of specific interest because they constitute an interface between a solid phase under complex evolution triggered by energetic processes and surface reactions, with a rich chemistry taking place in the gas phase. The interstellar ice mantles present in these environments are immersed, in addition to other existing radiations fields, in a flux of cosmic ray particles that can produce new species via radiolysis processes, but first affects their structure, which may change and also induces desorption of molecules and radicals from these grains. Theses cosmic rays are simulated by swift ions in the laboratory for a better understanding of astrophysical processes. (C) 2015 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000366787000007,
author = {Dartois, E. and Auge, B. and Rothard, H. and Boduch, P. and Brunetto, R. and Chabot, M. and Domaracka, A. and Ding, J. -J. and Kamalou, O. and Lv, X. -Y. and Frota da Silveira, E. and Thomas, J. -C. and Pino, T. and Mejia, C. and Godard, M. and de Barros, A. L. F.},
title = {Swift heavy ion modifications of astrophysical water ice},
journal = {NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS},
year = {2015},
volume = {365},
number = {B},
pages = {472-476},
doi = {10.1016/j.nimb.2015.08.053}
}
|
| "Revisited water radiolysis at elevated pH by accounting O-3(center dot-) kinetics at low and high LET" El Omar AK, Baldacchino G, Monnet I and Bouniol P , RSC ADVANCES. Vol. {5}({108}), pp. {89244-89253}. (2015). |
| Abstract: Ozonide radical, O-3(center dot-), is used in this study for probing radiolytic species formed in the radiolysis of liquid water at elevated pH. Its formation allows the scavenging of O center dot- whereas its disappearing is due to its reactions with HO2- and O-2(center dot-). This article focuses on the formation and the reaction of O-3(center dot-) at pH 13.2 by using pulse radiolysis technique, with 10 MeV electrons and 1 GeV C6+ ions beams for the first time. This allowed us to work with two different Linear Energy Transfer (LET) values (0.27 and 33 eV nm(-1) respectively), which means with two different primary distributions of radiolytic species. Consequently the rates constant of reactions O-3(center dot-) + HO2- and O-3(center dot-) + O-2(center dot-) could be revised with acceptable accuracy thanks to deterministic simulations: (1.1 +/- 0.2) x 10(6) M-1 s(-1) and (1.5 +/- 0.5) x 10(7) M-1 s(-1) respectively. Furthermore, the primary radiolytic yields of HO center dot/O center dot- and H2O2/HO2- at high LET and pH 13.2 were estimated at 6.5 and 9.6 x 10(-8) mol J(-1) respectively which corresponds to the literature values. |
BibTeX:
@article{ISI:000363417900089,
author = {El Omar, A. K. and Baldacchino, G. and Monnet, I. and Bouniol, P.},
title = {Revisited water radiolysis at elevated pH by accounting O-3(center dot-) kinetics at low and high LET},
journal = {RSC ADVANCES},
year = {2015},
volume = {5},
number = {108},
pages = {89244-89253},
doi = {10.1039/c5ra16858a}
}
|
| "Self-Radiolysis of Tritiated Water Stored in Zeolites 4A: Production and Behavior of H-2 and O-2" Frances L, Douilly M, Grivet M, Ducret D and Theobald M, JOURNAL OF PHYSICAL CHEMISTRY C., DEC 24, {2015}. Vol. {119}({51}), pp. {28462-28469}. (2015). |
| Abstract: Radiolysis of confined water and self-radiolysis of tritiated water give rise to several unanswered questions. To take into account this double specificity, we studied systems of zeolites 4A containing tritiated water at different water loading ratios. Two tritiated waters were synthesized at the volumetric activities of 27 and 60 TBq L-1. For each one, five samples were prepared, differentiated by their water loading ratios, expressed in percentage, close to 4 7 11 14 and 19 The study of the radiolysis in those systems revealed a double role of zeolites 4A: first, they increase the decomposition of water. Then they enhance the recombination of the major stable radiolytic products detected. We actually evidenced a total recombination between H-2 and O-2, which is catalyzed by the zeolites. |
BibTeX:
@article{ISI:000367561700026,
author = {Frances, Laetitia and Douilly, Mikael and Grivet, Manuel and Ducret, Didier and Theobald, Marc},
title = {Self-Radiolysis of Tritiated Water Stored in Zeolites 4A: Production and Behavior of H-2 and O-2},
journal = {JOURNAL OF PHYSICAL CHEMISTRY C},
year = {2015},
volume = {119},
number = {51},
pages = {28462-28469},
doi = {10.1021/acs.jpcc.5b10243}
}
|
| "Hydrogen radiolytic release from zeolite 4A/water systems under gamma irradiations" Frances L, Grivet M, Renault J-P, Groetz J-E and Ducret D , RADIATION PHYSICS AND CHEMISTRY., MAY, {2015}. Vol. {110}, pp. {6-11}. (2015). |
| Abstract: Although the radiolysis of bulk water is well known, some questions remain in the case of adsorbed or confined water, especially in the case of zeolites 4A, which are used to store tritiated water. An enhancement of the production of hydrogen is described in the literature for higher porous structures, but the phenomenon stays unexplained. We have studied the radiolysis of zeolites 4A containing different quantities of water under Cs-137 gamma radiation. We focused on the influence of the water loading ratio. The enhancement of hydrogen production compared with bulk water radiolysis has been attributed to the energy transfer from the zeolite to the water, and to the influence of the water structure organization in the zeolite. Both were observed separately, with a maximum efficiency for energy transfer at a loading ratio of about 13 and a maximum impact of structuration of water at a loading ratio of about 4 (C) 2015 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000350932400002,
author = {Frances, Laetitia and Grivet, Manuel and Renault, Jean-Philippe and Groetz, Jean-Emmanuel and Ducret, Didier},
title = {Hydrogen radiolytic release from zeolite 4A/water systems under gamma irradiations},
journal = {RADIATION PHYSICS AND CHEMISTRY},
year = {2015},
volume = {110},
pages = {6-11},
doi = {10.1016/j.radphyschem.2015.01.008}
}
|
| "Alpha radiolysis of nitric acid and sodium nitrate with He-4(2+) beam of 13.5 MeV energy" Garaix G, Venault L, Costagliola A, Maurin J, Guigue M, Omnee R, Blain G, Vandenborre J, Fattahi M, Vigier N and Moisy P, RADIATION PHYSICS AND CHEMISTRY., JAN, {2015}. Vol. {106}, pp. {394-403}. (2015). |
| Abstract: A study of aqueous nitric acid solution alpha radiolysis was performed through experiments carried out at a cyclotron facility, where a helion beam with an energy of 13.5 MeV could be delivered into the solution. The effects of nitrate and hydronium ions on the formation yields of hydrogen peroxide and nitrous acid, G(H2O2) and G(HNO2), were studied. The results showed that G(H2O2) decreases linearly with increasing nitrate ion concentration. On the other hand, G(HNO2) increases with the nitrate ion concentration until it reaches a plateau for nitric acid concentrations higher than 2 mol L-1. It was also found that an increase of hydronium ion concentration has a favorable effect on G(H2O2) and G(HNO2). Furthermore, it appears that these effects are additive and that the variations of G(H2O2) and G(HNO2) can be described by two parametric expressions, as a function of the nitrate and hydronium ion concentrations. (C) 2014 Published by Elsevier Ltd. |
BibTeX:
@article{ISI:000344422400058,
author = {Garaix, G. and Venault, L. and Costagliola, A. and Maurin, J. and Guigue, M. and Omnee, R. and Blain, G. and Vandenborre, J. and Fattahi, M. and Vigier, N. and Moisy, P.},
title = {Alpha radiolysis of nitric acid and sodium nitrate with He-4(2+) beam of 13.5 MeV energy},
journal = {RADIATION PHYSICS AND CHEMISTRY},
year = {2015},
volume = {106},
pages = {394-403},
doi = {10.1016/j.radphyschem.2014.08.008}
}
|
| "Conducting polymer-supported palladium nanoplates for applications in direct alcohol oxidation" Ghosh S, Teillout A-L, Floresyona D, de Oliveira P, Hagege A and Remita H, INTERNATIONAL JOURNAL OF HYDROGEN ENERGY., APR 20, {2015}. Vol. {40}({14}), pp. {4951-4959}. (2015). |
| Abstract: Nanostructured materials play a critical role in the catalysis of various relevant reactions in fuel cells, resulting in enhanced intrinsic electroactivity with high surface area, superior conductivity and better mass transport. The catalytic activity and stability of Pd nanoplates (Pd-NPLs) for the oxidation of ethanol were studied by using cyclic voltammetry and chronoamperometry. The poly(diphenylbutadyine) (PDPB) polymer nanofiber can be used as support to enhance the catalytic activity of Pd nanoplates for the oxidation of ethanol. The chronoamperometric response confirms the better activity and stability of the nanofiber-based support compared to commercial nafion (5 wt. The nanofiber morphology of the poly(diphenylbutadyine) polymer helps in the effective dispersion of the Pd nanoplates, facilitating an easier access of ethanol molecules to the catalytic sites. The dispersion of the Pd nanoplates within the polymer nanofibers is connected with an enhancement of the catalytic activity. These results show that the polymer-supported Pd nanoplate based hybrid structure is a promising anode catalyst in direct alcohol fuel cells (DAPCs). Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000352666600027,
author = {Ghosh, Srabanti and Teillout, Anne-Lucie and Floresyona, Dita and de Oliveira, Pedro and Hagege, Agnes and Remita, Hynd},
title = {Conducting polymer-supported palladium nanoplates for applications in direct alcohol oxidation},
journal = {INTERNATIONAL JOURNAL OF HYDROGEN ENERGY},
year = {2015},
volume = {40},
number = {14},
pages = {4951-4959},
doi = {10.1016/j.ijhydene.2015.01.101}
}
|
| "High temperature Raman study of UO2: A possible tool for in situ estimation of irradiation-induced heating" Guimbretiere G, Canizares A, Raimboux N, Joseph J, Desgardin P, Desgranges L, Jegou C and Simon P, JOURNAL OF RAMAN SPECTROSCOPY., APR, {2015}. Vol. {46}({4}), pp. {418-420}. (2015). |
| Abstract: Recently, in situ Raman setups under irradiation become available, and uranium dioxide is one of the most studied compounds. This paper reports the temperature dependence of the only Raman-active mode in fluorine UO2. Besides the interest in terms of phonon anharmonicity knowledge, this can be used to estimate the heating induced by irradiation: The frequency shift and width of the T-2g peak can be used as an internal indirect probe of the local temperature in the 20-590 degrees C range. Copyright (c) 2015 John Wiley & Sons, Ltd. |
BibTeX:
@article{ISI:000352636600011,
author = {Guimbretiere, G. and Canizares, A. and Raimboux, N. and Joseph, J. and Desgardin, P. and Desgranges, L. and Jegou, C. and Simon, P.},
title = {High temperature Raman study of UO2: A possible tool for in situ estimation of irradiation-induced heating},
journal = {JOURNAL OF RAMAN SPECTROSCOPY},
year = {2015},
volume = {46},
number = {4},
pages = {418-420},
doi = {10.1002/jrs.4661}
}
|
| "AComDim as a multivariate tool to analyse experimental design application to gamma-irradiated and leached ion exchange resins" Korifi R, Amat S, Rebufa C, Labed V, Rutledge DN and Dupuy N , CHEMOMETRICS AND INTELLIGENT LABORATORY SYSTEMS., FEB 15, {2015}. Vol. {141}, pp. {12-23}. (2015). |
| Abstract: gamma-Irradiations of ion exchange resins were carried out under various experimental conditions, selected using an experimental design, to simulate the ageing of such nuclear wastes. Those resins are a commercial mixed bed, constituted of 75 wt.% of a cationic resin and 25 wt.% of an anionic resin, and both are pure cationic and anionic resins. Then, irradiated samples were leached, at two different temperatures (20 degrees C and 50 degrees C). Solid matrices were characterized by a spectroscopic technique and spectral data were analysed by the ANOVA Common Dimensions (AComDim) method to detect and highlight influential factors and interactions. Four factors were studied (absorbed dose under irradiation, atmosphere during irradiation, dose rate, leaching temperature and resin type) with several levels for each. In a first study of the separate resins, the absorbed dose and the irradiation atmosphere appeared as the most influencing factors for the anionic resin. The leaching temperature was significant but only in interaction with other factors, while this parameter was significant for the cationic and mixed bed resins. In a global study of all the spectral data, the resin type appeared as the most influential factor for the radiolysis of resins. (C) 2014 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000350096200002,
author = {Korifi, R. and Amat, S. and Rebufa, C. and Labed, V. and Rutledge, D. N. and Dupuy, N.},
title = {AComDim as a multivariate tool to analyse experimental design application to gamma-irradiated and leached ion exchange resins},
journal = {CHEMOMETRICS AND INTELLIGENT LABORATORY SYSTEMS},
year = {2015},
volume = {141},
pages = {12-23},
doi = {10.1016/j.chemolab.2014.12.003}
}
|
| "Aging of magnesium stearate under high doses gamma irradiation and oxidative conditions" Lebeau D, Beuvier L, Cornaton M, Miserque F, Tabarant M, Esnouf S and Ferry M, JOURNAL OF NUCLEAR MATERIALS., MAY, {2015}. Vol. {460}, pp. {130-138}. (2015). |
| Abstract: In nuclear waste packages conditioning processes, magnesium stearate is widely used because of its high lubricating properties. For safety purposes, the radiolytic degradation of these organic materials has to be better understood to be able to predict their aging in repository conditions. This study reports the radiolytic degradation of magnesium stearate, using gamma-rays at room temperature and under air. Modifications were followed using different analytical tools (XPS, ATR-FTIR, ICP-AES, ATG and mass spectrometry). It has been observed that molecules mainly formed up to 1000 kGy of gamma irradiation dose under radio-oxidation are alkanes, hydroperoxides, double bonds in the aliphatic chain, carboxylates with aliphatic chain shorter than the one of stearate and ketones. At a dose of 4000 kGy, dicarboxylic acids are observed: the formation of these molecules needs a dose of at least 1000 kGy to be created under radio-oxidation. These observations allow us to propose a non-exhaustive degradation mechanism of magnesium stearate under gamma-irradiation at room temperature and under air. (C) 2015 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000352172500017,
author = {Lebeau, D. and Beuvier, L. and Cornaton, M. and Miserque, F. and Tabarant, M. and Esnouf, S. and Ferry, M.},
title = {Aging of magnesium stearate under high doses gamma irradiation and oxidative conditions},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2015},
volume = {460},
pages = {130-138},
doi = {10.1016/j.jnucmat.2015.02.016}
}
|
| "Oxidizing dissolution mechanism of an irradiated MOX fuel in underwater aerated conditions at slightly acidic pH" Magnin M, Jegou C, Caraballo R, Broudic V, Tribet M, Peuget S and Talip Z , JOURNAL OF NUCLEAR MATERIALS., JUL, {2015}. Vol. {462}, pp. {230-241}. (2015). |
| Abstract: The (U,Pu)O-2 matrix behavior of an irradiated MIMAS-type (MIcronized MASter blend) MOX fuel, under radiolytic oxidation in aerated pure water at pH 5-5.5 was studied by combining chemical and radiochemical analyses of the alteration solution with Raman spectroscopy characterizations of the surface state. Two leaching experiments were performed on segments of irradiated fuel under different conditions: with or without an external gamma irradiation field, over long periods (222 and 604 days, respectively). The gamma irradiation field was intended to be representative of the irradiation conditions for a fuel assembly in an underwater interim storage situation. The data acquired enabled an alteration mechanism to be established, characterized by uranium(UO22+) release mainly controlled by solubility of studtite over the long-term. The massive precipitation of this phase was observed for the two experiments based on high uranium oversaturation indexes of the solution and the kinetics involved depended on the irradiation conditions. External gamma irradiation accelerated the precipitation kinetics and the uranium concentrations (2.9 x 10(-7) mol/l) were lower than for the non-irradiated reference experiment (1.4 x 10(-5) mol/l), as the quantity of hydrogen peroxide was higher. Under slightly acidic pH conditions, the formation of an oxidized UO2+x phase was not observed on the surface and did not occur in the radiolysis dissolution mechanism of the fuel matrix. The Raman spectroscopy performed on the heterogeneous MOX fuel matrix surface, showed that the fluorite structure of the mainly UO2 phase surrounding the Pu-enriched aggregates had not been particularly impacted by any major structural change compared to the data obtained prior to leaching. For the plutonium, its behavior in solution involved a continuous release up to concentrations of approximately 3 x 10(-6) mol L-1 with negligible colloid formation. This data appears to support a predominance of the +V oxidation state for plutonium in solution under highly oxidizing conditions. Furthermore, the Raman spectroscopy monitoring of the sample surface oxidation states did not point to any significant effect from the high Pu content of the aggregates (10-15 and therefore did not indicate a better aggregate stability under radiolysis compared to the mainly UO2 matrix. This is because acidic pH conditions do not favor the development of oxidized layers on a fuel surface, with the exception of secondary phases. (C) 2015 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000357545900026,
author = {Magnin, M. and Jegou, C. and Caraballo, R. and Broudic, V. and Tribet, M. and Peuget, S. and Talip, Z.},
title = {Oxidizing dissolution mechanism of an irradiated MOX fuel in underwater aerated conditions at slightly acidic pH},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2015},
volume = {462},
pages = {230-241},
doi = {10.1016/j.jnucmat.2015.03.029}
}
|
| "Radiolysis and sputtering of carbon dioxide ice induced by swift Ti, Ni, and Xe ions" Mejia C, Bender M, Severin D, Trautmann C, Boduch P, Bordalo V, Domaracka A, Lv XY, Martinez R and Rothard H, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS., DEC 15, {2015}. Vol. {365}({B}), pp. {477-481}. (2015). |
| Abstract: Solid carbon dioxide (CO2) is found in several bodies of the solar system, the interstellar medium (ISM) and young stellar objects, where it is exposed to cosmic and stellar wind radiation. Here, the chemical and physical modifications induced by heavy ion irradiation of pure solid CO2 at low temperature (T = 15-30 K) are analyzed. The experiments were performed with Ti (550 MeV) and Xe (630 MeV) ions at the UNILAC of GSI/Darmstadt and with Ni ions (46 and 52 MeV) at IRRSUD of GANIL/Caen. The evolution of the thin CO2 ice films (deposited on a Csl window) was monitored by mid-infrared absorption spectroscopy (FTIR). The dissociation rate of CO2, determined from the fluence dependence of the IR absorption peak intensity, is found to be proportional to the electronic stopping power S-e. We also confirm that the sputtering yield shows a quadric increase with electronic stopping power. Furthermore, the production rates of daughter molecules such as CO, CO3 and O-3 were found to be linear in S-e. (C) 2015 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000366787000008,
author = {Mejia, C. and Bender, M. and Severin, D. and Trautmann, C. and Boduch, Ph and Bordalo, V. and Domaracka, A. and Lv, X. Y. and Martinez, R. and Rothard, H.},
title = {Radiolysis and sputtering of carbon dioxide ice induced by swift Ti, Ni, and Xe ions},
journal = {NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS},
year = {2015},
volume = {365},
number = {B},
pages = {477-481},
doi = {10.1016/j.nimb.2015.09.039}
}
|
| "Determination of alpha dose rate profile at the HLW nuclear glass/water interface" Mougnaud S, Tribet M, Rolland S, Renault JP and Jegou C, JOURNAL OF NUCLEAR MATERIALS., JUL, {2015}. Vol. {462}, pp. {258-267}. (2015). |
| Abstract: Alpha irradiation and radiolysis can affect the alteration behavior of High Level Waste (HLW) nuclear glasses. In this study, the way the energy of alpha particles, emitted by a typical HLW glass, is deposited in water at the glass/water interface is investigated, with the aim of better characterizing the dose deposition at the glass/water interface during water-induced leaching mechanisms. A simplified chemical composition was considered for the nuclear glass under study, wherein the dose rate is about 140 Gy/h. The MCNPX calculation code was used to calculate alpha dose rate and alpha particle flux profiles at the glass/water interface in different systems: a single glass grain in water, a glass powder in water and a water-filled ideal crack in a glass package. Dose rate decreases within glass and in water as distance to the center of the grain increases. A general model has been proposed to fit a dose rate profile in water and in glass from values for dose rate in glass bulk, alpha range in water and linear energy transfer considerations. The glass powder simulation showed that there was systematic overlapping of radiation fields for neighboring glass grains, but the water dose rate always remained lower than the bulk value. Finally, for typical ideal cracks in a glass matrix, an overlapping of irradiation fields was observed while the crack aperture was lower than twice the alpha range in water. This led to significant values for the alpha dose rate within the crack volume, as long as the aperture remained lower than 60 mu m. (C) 2015 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000357545900029,
author = {Mougnaud, S. and Tribet, M. and Rolland, S. and Renault, J. -P. and Jegou, C.},
title = {Determination of alpha dose rate profile at the HLW nuclear glass/water interface},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2015},
volume = {462},
pages = {258-267},
doi = {10.1016/j.jnucmat.2015.04.012}
}
|
| "Electrolytes Ageing in Lithium-ion Batteries: A Mechanistic Study from Picosecond to Long Timescales" Ortiz D, Gordon IJ, Baltaze J-P, Hernandez-Alba O, Legand S, Dauvois V, Larbi GS, Schmidhammer U, Marignier J-L, Martin J-F, Belloni J, Mostafavi M and Le Caer S , CHEMSUSCHEM., NOV 9, {2015}. Vol. {8}({21}), pp. {3605-3616}. (2015). |
| Abstract: The ageing phenomena occurring in various diethyl carbonate/LiPF6 solutions are studied using gamma and pulse radiolysis as a tool to generate similar species as the ones occurring in electrolysis of Li-ion batteries (LIBs). According to picosecond pulse radiolysis experiments, the reaction of the electron with (Li+, PF6-) is ultrafast, leading to the formation of fluoride anions that can then precipitate into LiF(s). Moreover, direct radiation-matter interaction with the salt produces reactive fluorine atoms forming HF(g) and C2H5F(g). The strong Lewis acid PF5 is also formed. This species then forms various (RRRP)-R-1-R-2-P-3=O molecules, where R is mainly -F, -OH, and -OC2H5. Substitution reactions take place and oligomers are slowly formed. Similar results were obtained in the ageing of an electrochemical cell filled with the same model solution. This study demonstrates that radiolysis enables a description of the reactivity in LIBs from the picosecond timescale until a few days. |
BibTeX:
@article{ISI:000364525800010,
author = {Ortiz, Daniel and Gordon, Isabel Jimenez and Baltaze, Jean-Pierre and Hernandez-Alba, Oscar and Legand, Solene and Dauvois, Vincent and Larbi, Gregory Si and Schmidhammer, Uli and Marignier, Jean-Louis and Martin, Jean-Frederic and Belloni, Jacqueline and Mostafavi, Mehran and Le Caer, Sophie},
title = {Electrolytes Ageing in Lithium-ion Batteries: A Mechanistic Study from Picosecond to Long Timescales},
journal = {CHEMSUSCHEM},
year = {2015},
volume = {8},
number = {21},
pages = {3605-3616},
doi = {10.1002/cssc.201500641}
}
|
| "Radiolysis as a solution for accelerated ageing studies of electrolytes in Lithium-ion batteries" Ortiz D, Steinmetz V, Durand D, Legand S, Dauvois V, Maitre P and Le Caer S, NATURE COMMUNICATIONS., APR, {2015}. Vol. {6}, (2015). |
| Abstract: Diethyl carbonate and dimethyl carbonate are prototype examples of eco-friendly solvents used in lithium-ion batteries. Nevertheless, their degradation products affect both the battery performance and its safety. Therefore, it is of paramount importance to understand the reaction mechanisms involved in the ageing processes. Among those, redox processes are likely to play a critical role. Here we show that radiolysis is an ideal tool to generate the electrolytes degradation products. The major gases detected after irradiation (H-2, CH4, C2H6, CO and CO2) are identified and quantified. Moreover, the chemical compounds formed in the liquid phase are characterized by different mass spectrometry techniques. Reaction mechanisms are then proposed. The detected products are consistent with those of the cycling of Li-based cells. This demonstrates that radiolysis is a versatile and very helpful tool to better understand the phenomena occurring in lithium-ion batteries. |
BibTeX:
@article{ISI:000353704700002,
author = {Ortiz, Daniel and Steinmetz, Vincent and Durand, Delphine and Legand, Solene and Dauvois, Vincent and Maitre, Philippe and Le Caer, Sophie},
title = {Radiolysis as a solution for accelerated ageing studies of electrolytes in Lithium-ion batteries},
journal = {NATURE COMMUNICATIONS},
year = {2015},
volume = {6},
doi = {10.1038/ncomms7950}
}
|
| "Experimental design approach for identification of the factors influencing the gamma-radiolysis of ion exchange resins" Rebufa C, Traboulsi A, Labed V, Dupuy N and Sergent M , RADIATION PHYSICS AND CHEMISTRY., JAN, {2015}. Vol. {106}, pp. {223-234}. (2015). |
| Abstract: Gamma radiolysis was investigated on a nuclear grade mixed bed ion exchange resin and its pure components under different irradiation conditions. Screening designs were performed to identify the factors influencing gas production after their gamma-radiolysis and to compare their gamma-degradation stability. Only hydrogen and trimethylamine quantities were considered as the response in the experimental designs. The other detected gases and water-soluble products were used to improve the resins degradation. Aerobic irradiation atmosphere decreased the H-2g production of AmbOH, MB400, and amines. The water presence increased the H-2g quantities for AmbH and decreased those for MB400 resin. Liquid water had no effect on H-2g production from AmbOH but was favorable to increased amine production. The H-2g production of AmbH increased with the absorbed dose that had little effect on the AmbOH resin. No impact of dose on the H-2g production was detected for MB400 that appeared to be less degraded. (C) 2014 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000344422400034,
author = {Rebufa, C. and Traboulsi, A. and Labed, V. and Dupuy, N. and Sergent, M.},
title = {Experimental design approach for identification of the factors influencing the gamma-radiolysis of ion exchange resins},
journal = {RADIATION PHYSICS AND CHEMISTRY},
year = {2015},
volume = {106},
pages = {223-234},
doi = {10.1016/j.radphyschem.2014.07.020}
}
|
| "Electrochemical behaviour of 316L stainless steel exposed to representative chemistry in pressurised water reactors under proton radiation" Wang M, Perrin S, Corbel C and Feron D), JOURNAL OF ELECTROANALYTICAL CHEMISTRY., JAN 15, {2015}. Vol. {737}({SI}), pp. {141-149}. (2015). |
| Abstract: The electrochemical behaviour of 316L stainless steel has been investigated in representative primary PWR environment under proton irradiation. The electrochemical potential of 316L stainless steel and the environmental parameters (temperature, hydrogen pressure, etc.) have been measured continuously under irradiation. Highly reproductive electrochemical results have been observed with fast increases of the potentials under irradiation. This oxidative response increases with increasing flux and decreases with increasing hydrogen pressure. Depending on the temperature, the oxidative response can either be reduced or enhanced. Moreover, the synergetic effect of thermal ageing and cumulated fluence on 316L stainless steel can influence the electrochemical potential with or without irradiation. (C) 2014 Published by Elsevier B.V. |
BibTeX:
@article{ISI:000349508300017,
author = {Wang, M. and Perrin, S. and Corbel, C. and Feron, D.},
title = {Electrochemical behaviour of 316L stainless steel exposed to representative chemistry in pressurised water reactors under proton radiation},
journal = {JOURNAL OF ELECTROANALYTICAL CHEMISTRY},
year = {2015},
volume = {737},
number = {SI},
pages = {141-149},
doi = {10.1016/j.jelechem.2014.10.015}
}
|
| 2014 |
| "Acetone degradation by cosmic rays in the solar neighbourhood and in the Galactic Centre" Andrade DPP, de Barros ALF, Ding J, Rothard H, Boduch P and da Silveira EF, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY., NOV 11, {2014}. Vol. {444}({4}), pp. {3792-3801}. (2014). |
| Abstract: Acetone (CH3COCH3) was the first molecule with 10 atoms found in the interstellar medium. This molecule was found towards the hot molecular core Sagittarius B2 (N-LHM) and in the Orion-KL star-forming region towards the hot core. Laboratory data, such as the formation and destruction cross-sections and the half-life of the molecules, combined with theoretical calculations and astronomical observations, can help us to elucidate the processes that occur in the astronomical sources. In this work, we study the radiolysis of acetone ice by 40-MeV Ni-58(11) + ions at 16 K. Pure acetone ice was bombarded with nickel ions, which are cosmic ray constituents that are highly efficient at inducing chemical reaction in ices, in order to provide experimental data for a model describing interaction with similar heavy constituents of cosmic rays (with z >= 10). The dissociation rate of pure acetone and its half-life in the interstellar medium in close proximity to the solar system and the Galactic Centre due to the main ions (H, He, C, Mg, O, Si, Fe, Ni) are predicted from recorded spectra and the current analysis. The formation of new molecular species by cosmic rays is discussed and the atom budget is analysed. The formation cross-section of species, as well as the penetration depth of some light and heavy ions, are also calculated. We present a discussion on the energy lost and the penetration depth of acetone ice. |
BibTeX:
@article{ISI:000343400100059,
author = {Andrade, Diana P. P. and de Barros, Ana L. F. and Ding, Jingjie and Rothard, Hermann and Boduch, Philippe and da Silveira, Enio F.},
title = {Acetone degradation by cosmic rays in the solar neighbourhood and in the Galactic Centre},
journal = {MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
year = {2014},
volume = {444},
number = {4},
pages = {3792-3801},
doi = {10.1093/mnras/stu1519}
}
|
| "The influence of radioactive decay on actinide magnetic susceptibility measurements obtained using the Evans method" Autillo M, Kaden P, Geist A, Guerin L, Moisy P and Berthon C, PHYSICAL CHEMISTRY CHEMICAL PHYSICS. Vol. {16}({18}), pp. {8608-8614}. (2014). |
| Abstract: In order to explain the higher magnetic susceptibility of some aquo actinide ions than predicted by Hund's rules, the molar magnetic susceptibilities of two americium isotopes (Am-241 and Am-243) were measured using the Evans method. The results obtained show a growing change in the magnetic susceptibility with alpha and also a beta(-) activity increase in solution. beta(-) particle effects appear to be stronger than radicals formed by alpha particles on the experimental values. The temperature dependence of Am(III) magnetic susceptibility has been observed but from experiments carried out here, it appears to be difficult to prove whether this effect arises from radicals or beta(-). Finally, magnetic susceptibilities of americium recorded in different media (HClO4, HCl, and HNO3) have been compared to alpha and beta emissions' impact. |
BibTeX:
@article{ISI:000334602900049,
author = {Autillo, Matthieu and Kaden, Peter and Geist, Andreas and Guerin, Laetitia and Moisy, Philippe and Berthon, Claude},
title = {The influence of radioactive decay on actinide magnetic susceptibility measurements obtained using the Evans method},
journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},
year = {2014},
volume = {16},
number = {18},
pages = {8608-8614},
doi = {10.1039/c4cp00724g}
}
|
| "First observation of HO center dot reactivity in water under high energy ions at elevated temperature" Balcerzyk A, Boughattas I, Pin S, Balanzat E and Baldacchino G, PHYSICAL CHEMISTRY CHEMICAL PHYSICS. Vol. {16}({43}), pp. {23975-23984}. (2014). |
| Abstract: This communication reports the first observation of the formation of HO center dot produced under two different High energy ion beams, O-18(8+) and Ar-36(18+) having Linear Energy Transfers (LET) of 65 and 350 eV nm(-1) respectively, at temperatures up to 411 K. Both scavenging with various concentrations of SCN- and heavy-ion pulse radiolysis methods are used with an original temperature and pressure regulated optical cell. Deconvolution of kinetics is used to analyze the evolution of HO center dot track segment yields as a function of time and temperature. It takes care of involving the ionic strength effect and Arrhenius expression in the rate constants correction. The results show a fast decay of HO center dot yields in the 10(-10)-10(-8) s range which denotes an efficient reactivity of this species in the track structure of the ion beam. This effect is enhanced with the lowest LET of O8+. Increasing the temperature also accelerates the decays for both ions. These observations are discussed in terms of temperature activation of reactions and the track structure exhibiting the formation of HO center dot in a ``low LET'' penumbra around the ionization tracks. HO center dot track segment yields at 100 ns, of 0.4 x 10(-7) and 0.6 x 10(-7) mol J(-1), respectively for 350 and 65 eV nm(-1), are not affected by temperature. |
BibTeX:
@article{ISI:000343974100053,
author = {Balcerzyk, A. and Boughattas, I. and Pin, S. and Balanzat, E. and Baldacchino, G.},
title = {First observation of HO center dot reactivity in water under high energy ions at elevated temperature},
journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},
year = {2014},
volume = {16},
number = {43},
pages = {23975-23984},
doi = {10.1039/c4cp03049d}
}
|
| "Processing of low carbon content interstellar ice analogues by cosmic rays: implications for the chemistry around oxygen-rich stars" de Barros ALF, da Silveira EF, Pilling S, Domaracka A, Rothard H and Boduch P, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY., MAR, {2014}. Vol. {438}({3}), pp. {2026-2035}. (2014). |
| Abstract: Radiolysis of a homogeneous H2O:H2CO:CH3OH (100:2:0.8) ice mixture by fast heavy ions is performed in the laboratory in an attempt to simulate the interaction of cosmic rays with frozen surfaces at 15 K. Bombarded by 220-MeV O-16(7 +) ions, the ice layer is thin enough to be traversed by projectiles at approximately constant velocity and with charge states close to the equilibrium one. Analysis by Fourier transform infrared spectroscopy (FTIR) reveals that the molecular species formed are CH4, CO2, CO, HCO, HCOO- and CH3OCHO. The formation and dissociation cross-sections of all observed daughter molecules are determined. As a control procedure, a carbon budget is performed as the beam fluence increases. The observed radiation effects lead to a general observation that the destruction cross-sections of condensed gases by heavy ions are ruled by a power law that is a function of the electronic stopping power: sigma(d) similar to S-e(n) , where n is approximately 3/2. This relation is observed for the destruction of precursor H2CO molecules and for the formation of daughter species. The present results help our understanding of the chemical and physicochemical interactions induced by heavy cosmic rays in cold astrophysical environments with low carbon contents, such as those around oxygen-rich stars. |
BibTeX:
@article{ISI:000331877000007,
author = {de Barros, A. L. F. and da Silveira, E. F. and Pilling, S. and Domaracka, A. and Rothard, H. and Boduch, P.},
title = {Processing of low carbon content interstellar ice analogues by cosmic rays: implications for the chemistry around oxygen-rich stars},
journal = {MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
year = {2014},
volume = {438},
number = {3},
pages = {2026-2035},
doi = {10.1093/mnras/stt2305}
}
|
| "Chemical and physical effects induced by heavy cosmic ray analogues on frozen methanol and water ice mixtures" de Barros ALF, da Silveira EF, Rothard H, Langlinay T and Boduch P, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY., SEP 21, {2014}. Vol. {443}({3}), pp. {2733-2745}. (2014). |
| Abstract: The chemical and physical effects induced by fast heavy-ion irradiation on a frozen mixture of methanol (CH3OH) and water (H2O) at 15 K are analysed. The laboratory experiment described here simulates the energy transfer processes that occur when cosmic rays bombard this particular ice mixture and helps to elucidate the understanding of the radiolysis of ices occurring in interstellar medium grains, at the surfaces of comets, and on icy Solar system bodies. Infrared spectroscopy (FTIR) was used before and during irradiation with a 40 MeV Ni-58(11+) ion beam to determine the variation of the main absorption bands of methanol, water and products. In particular, the radiolysis of CH3OH:H2O (1:1) mixture leads to the formation of H2CO, CH4, CO, CO2, HCO and HCOOCH3. Their formation and dissociation cross-sections are determined. H2CO, CH4 and HCOOCH3 molecules have relatively high destruction cross-sections of around 9 x 10(-13) cm(2). Furthermore, atomic carbon, oxygen and hydrogen budgets are determined and used to verify the stoichiometry of the most abundant molecular species formed. Temperature effects are compared with irradiation effects, and the spectra of samples warmed-up to different temperatures are compared with those of the irradiated CH3OH:H2O mixtures. As an astrophysical application, the CH3OH:H2O dissociation cross-sections due to other ion beam projectiles and energies are predicted assuming validity of the S-e(3/2) power law; calculation of the integrated dissociation rates confirms the importance of nickel and some other heavy-ion constituents of cosmic rays in astrochemistry. |
BibTeX:
@article{ISI:000342920400063,
author = {de Barros, A. L. F. and da Silveira, E. F. and Rothard, H. and Langlinay, T. and Boduch, P.},
title = {Chemical and physical effects induced by heavy cosmic ray analogues on frozen methanol and water ice mixtures},
journal = {MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
year = {2014},
volume = {443},
number = {3},
pages = {2733-2745},
doi = {10.1093/mnras/stu1208}
}
|
| "One-electron oxidation reactions of purine and pyrimidine bases in cellular DNA" Cadet J, Wagner JR, Shafirovich V and Geacintov NE, INTERNATIONAL JOURNAL OF RADIATION BIOLOGY., JUN, {2014}. Vol. {90}({6}), pp. {423-432}. (2014). |
| Abstract: Purpose : The aim of this survey is to critically review the available information on one-electron oxidation reactions of nucleobases in cellular DNA with emphasis on damage induced through the transient generation of purine and pyrimidine radical cations. Since the indirect effect of ionizing radiation mediated by hydroxyl radical is predominant in cells, efforts have been made to selectively ionize bases using suitable one-electron oxidants that consist among others of high intensity UVC laser pulses. Thus, the main oxidation product in cellular DNA was found to be 8-oxo-7,8-dihydroguanine as a result of direct bi-photonic ionization of guanine bases and indirect formation of guanine radical cations through hole transfer reactions from other base radical cations. The formation of 8-oxo-7,8-dihydroguanine and other purine and pyrimidine degradation products was rationalized in terms of the initial generation of related radical cations followed by either hydration or deprotonation reactions in agreement with mechanistic pathways inferred from detailed mechanistic studies. The guanine radical cation has been shown to be implicated in three other nucleophilic additions that give rise to DNA-protein and DNA-DNA cross-links in model systems. Evidence was recently provided for the occurrence of these three reactions in cellular DNA. Conclusion : There is growing evidence that one-electron oxidation reactions of nucleobases whose mechanisms have been characterized in model studies involving aqueous solutions take place in a similar way in cells. It may also be pointed out that the above cross-linked lesions are only produced from the guanine radical cation and may be considered as diagnostic products of the direct effect of ionizing radiation. |
BibTeX:
@article{ISI:000336909500003,
author = {Cadet, Jean and Wagner, J. Richard and Shafirovich, Vladimir and Geacintov, Nicholas E.},
title = {One-electron oxidation reactions of purine and pyrimidine bases in cellular DNA},
journal = {INTERNATIONAL JOURNAL OF RADIATION BIOLOGY},
year = {2014},
volume = {90},
number = {6},
pages = {423-432},
doi = {10.3109/09553002.2013.877176}
}
|
| "Electron Transfer at Oxide/Water Interfaces Induced by Ionizing Radiation" Chelnokov E, Cuba V, Simeone D, Guigner JM, Schmidhammer U, Mostafavi M and Le Caer S, JOURNAL OF PHYSICAL CHEMISTRY C., APR 17, {2014}. Vol. {118}({15}), pp. {7865-7873}. (2014). |
| Abstract: The electron transfer from oxide into water is studied in nanoparticle suspensions of various oxides (SiO2, ZnO, Al2O3, Nd2O3, Sm2O3, and Er2O3) by means of pulse and gamma radiolysis. The time-resolved and steady-state investigations of the present study demonstrate independently that whatever the band gap and the electron affinity of the oxide, the electron transfer always takes place in these nanometric systems: Irradiation generates hot electrons which have enough energy to cross the semiconductor-liquid interface. Moreover, picosecond measurements evidence that the spectrum of the solvated electron is the same as in water. Lastly, the decay of the solvated electron is similar on the picosecond to nanosecond time scale in water and in these suspensions, but it is clearly different on the nanosecond to microsecond time scale. |
BibTeX:
@article{ISI:000334730300014,
author = {Chelnokov, E. and Cuba, V. and Simeone, D. and Guigner, J. -M. and Schmidhammer, U. and Mostafavi, M. and Le Caer, S.},
title = {Electron Transfer at Oxide/Water Interfaces Induced by Ionizing Radiation},
journal = {JOURNAL OF PHYSICAL CHEMISTRY C},
year = {2014},
volume = {118},
number = {15},
pages = {7865-7873},
doi = {10.1021/jp501396a}
}
|
| "Electrochemical formation and reactivity of a manganese peroxo complex: acid driven H2O2 generation vs. O-O bond cleavage" Ching HYV, Anxolabehere-Mallart E, Colmer HE, Costentin C, Dorlet P, Jackson TA, Policar C and Robert M, CHEMICAL SCIENCE. Vol. {5}({6}), pp. {2304-2310}. (2014). |
| Abstract: The formation of a side-on peroxo [(MnL)-L-III(O-2)] complex (L = phenolato-containing pentadentate ligand), resulting from the reaction of electrochemically reduced O-2 and [(MnL)-L-II](+), is monitored in DMF using cyclic voltammetry, low temperature electronic absorption spectroscopy and electron paramagnetic resonance spectroscopy. Mechanistic studies based on cyclic voltammetry reveal that upon addition of a strong acid the Mn-O bond is broken, resulting in the release of H2O2, whereas in the presence of a weak acid the O-O bond is cleaved via a concerted dissociative electron transfer. This dichotomy of MO versus O-O bond cleavage is unprecedented for peroxomanganese(III) complexes and the latter offers a route for electrochemical O-2 activation by a manganese(II) complex. |
BibTeX:
@article{ISI:000336254500024,
author = {Ching, H. Y. Vincent and Anxolabehere-Mallart, Elodie and Colmer, Hannah E. and Costentin, Cyrille and Dorlet, Pierre and Jackson, Timothy A. and Policar, Clotilde and Robert, Marc},
title = {Electrochemical formation and reactivity of a manganese peroxo complex: acid driven H2O2 generation vs. O-O bond cleavage},
journal = {CHEMICAL SCIENCE},
year = {2014},
volume = {5},
number = {6},
pages = {2304-2310},
doi = {10.1039/c3sc53469c}
}
|
| "Behavior of Heptavalent Technetium in Sulfuric Acid under alpha-Irradiation: Structural Determination of Technetium Sulfate Complexes by X-ray Absorption Spectroscopy and First Principles Calculations" Denden I, Poineau F, Schlegel ML, Roques J, Solari PL, Blain G, Czerwinski KR, Essehli R, Barbet J and Fattahi M, JOURNAL OF PHYSICAL CHEMISTRY A., MAR 6, {2014}. Vol. {118}({9}), pp. {1568-1575}. (2014). |
| Abstract: The effect of alpha-radiolysis on the behavior of heptavalent technetium has been investigated in 13 and 18 M H2SO4. Irradiation experiments were performed using alpha-particles (He-4(2+), E = 68 MeV) generated by the ARRONAX cyclotron. UV-visible and X-ray absorption fine structure spectroscopic studies indicate that Tc(VII) is reduced to Tc(V) under alpha-irradiation. Extended X-ray absorption fine structure (EXAFS) spectroscopy measurements are consistent with the presence of mononuclear technetium sulfate complexes. Experimental results and density functional calculations show the formation of [TcO(HSO4)(3)(H2O)(OH)](-) and/or [TcO(HSO4)(3)(H2O)(2)] and [Tc(HSO4)(3)(SO4)-(H2O)] and/or [Tc(HSO4)(3)(SO4)(OH)](-) for 13 and 18 M H2SO4, respectively. |
BibTeX:
@article{ISI:000332756100003,
author = {Denden, I. and Poineau, F. and Schlegel, M. L. and Roques, J. and Solari, P. Lorenzo and Blain, G. and Czerwinski, K. R. and Essehli, R. and Barbet, J. and Fattahi, M.},
title = {Behavior of Heptavalent Technetium in Sulfuric Acid under alpha-Irradiation: Structural Determination of Technetium Sulfate Complexes by X-ray Absorption Spectroscopy and First Principles Calculations},
journal = {JOURNAL OF PHYSICAL CHEMISTRY A},
year = {2014},
volume = {118},
number = {9},
pages = {1568-1575},
doi = {10.1021/jp404967f}
}
|
| "Ultrahigh dose-rate FLASH irradiation increases the differential response between normal and tumor tissue in mice" Favaudon V, Caplier L, Monceau V, Pouzoulet F, Sayarath M, Fouillade C, Poupon M-F, Brito I, Hupe P, Bourhis J, Hall J, Fontaine J-J and Vozenin M-C , SCIENCE TRANSLATIONAL MEDICINE., JUL 16, {2014}. Vol. {6}({245}), (2014). |
| Abstract: In vitro studies suggested that sub-millisecond pulses of radiation elicit less genomic instability than continuous, protracted irradiation at the same total dose. To determine the potential of ultrahigh dose-rate irradiation in radiotherapy, we investigated lung fibrogenesis in C57BL/6J mice exposed either to short pulses (<= 500 ms) of radiation delivered at ultrahigh dose rate (>= 40 Gy/s, FLASH) or to conventional dose-rate irradiation (<= 0.03 Gy/s, CONV) in single doses. The growth of human HBCx-12A and HEp-2 tumor xenografts in nude mice and syngeneic TC-1 Luc(+) orthotopic lung tumors in C57BL/6J mice was monitored under similar radiation conditions. CONV (15 Gy) triggered lung fibrosis associated with activation of the TGF-beta (transforming growth factor-beta) cascade, whereas no complications developed after doses of FLASH below 20 Gy for more than 36 weeks after irradiation. FLASH irradiation also spared normal smooth muscle and epithelial cells from acute radiation-induced apoptosis, which could be reinduced by administration of systemic TNF-alpha (tumor necrosis factor-alpha) before irradiation. in contrast, FLASH was as efficient as CONV in the repression of tumor growth. Together, these results suggest that FLASH radiotherapy might allow complete eradication of lung tumors and reduce the occurrence and severity of early and late complications affecting normal tissue. |
BibTeX:
@article{ISI:000339661200004,
author = {Favaudon, Vincent and Caplier, Laura and Monceau, Virginie and Pouzoulet, Frederic and Sayarath, Mano and Fouillade, Charles and Poupon, Marie-France and Brito, Isabel and Hupe, Philippe and Bourhis, Jean and Hall, Janet and Fontaine, Jean-Jacques and Vozenin, Marie-Catherine},
title = {Ultrahigh dose-rate FLASH irradiation increases the differential response between normal and tumor tissue in mice},
journal = {SCIENCE TRANSLATIONAL MEDICINE},
year = {2014},
volume = {6},
number = {245},
doi = {10.1126/scitranslmed.3008973}
}
|
| "Chemical composition effects of methylene containing polymers on gas emission under gamma-irradiation" Ferry M, Dannoux-Papin A, Dely N, Legand S, Durand D, Roujou JL, Lamouroux C, Dauvois V, Coignet P, Cochin F and Esnouf S, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS., SEP 1, {2014}. Vol. {334}, pp. {69-76}. (2014). |
| Abstract: The presence of different chemical groups in methylene containing polymers can lead to very different behaviors under ionizing radiation. To better understand the effect of these groups on gas production under gamma-irradiation, especially on hydrogen formation, and to study the efficiency of energy transfer between chemical groups, several methylene containing polymers with different controlled group concentrations were studied in inert atmosphere. We analyzed the influence of the nature and position of the chemical group using methylene containing copolymers with aliphatic side-chains (different lengths), ester groups in the side-chains (different concentrations) and ester groups in the polymer backbone (different concentrations). Radiation chemical yields of H-2, CO, CO2 and CH4 were determined at room temperature by high resolution mass spectrometry. On the basis of these results, we attempt to obtain a better understanding of the mechanisms involved. It can be observed that crystallinity and aliphatic side-chain have no effect on hydrogen formation. On contrary, esters on side-chain and in the backbone have an important influence on hydrogen formation, with the most important effect when esters groups are in the backbone. In these two kind of materials, energy fraction transferred from methylene to ester groups has been quantified and only 10 wt% (or less) of ester groups are sufficient to protect effectively the aliphatic moiety. (C) 2014 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000340339300012,
author = {Ferry, M. and Dannoux-Papin, A. and Dely, N. and Legand, S. and Durand, D. and Roujou, J. L. and Lamouroux, C. and Dauvois, V. and Coignet, P. and Cochin, F. and Esnouf, S.},
title = {Chemical composition effects of methylene containing polymers on gas emission under gamma-irradiation},
journal = {NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS},
year = {2014},
volume = {334},
pages = {69-76},
doi = {10.1016/j.nimb.2014.05.007}
}
|
| "Polarizable Molecular Mechanics Studies of Cu(I)/Zn(II) Superoxide Dismutase: Bimetallic Binding Site and Structured Waters" Gresh N, El Hage K, Perahia D, Piquemal J-P, Berthomieu C and Berthomieu D, JOURNAL OF COMPUTATIONAL CHEMISTRY., NOV 5, {2014}. Vol. {35}({29}), pp. {2096-2106}. (2014). |
| Abstract: The existence of a network of structured waters in the vicinity of the bimetallic site of Cu/Zn-superoxide dismutase (SOD) has been inferred from high-resolution X-ray crystallography. Long-duration molecular dynamics (MD) simulations could enable to quantify the lifetimes and possible interchanges of these waters between themselves as well as with a ligand diffusing toward the bimetallic site. The presence of several charged or polar ligands makes it necessary to resort to second-generation polarizable potentials. As a first step toward such simulations, we benchmark in this article the accuracy of one such potential, sum of interactions between fragments Ab initio computed (SIBFA), by comparisons with quantum mechanics (QM) computations. We first consider the bimetallic binding site of a Cu/Zn-SOD, in which three histidines and a water molecule are bound to Cu(I) and three histidines and one aspartate are bound to Zn(II). The comparisons are made for different His6 complexes with either one or both cations, and either with or without Asp and water. The total net charges vary from zero to three. We subsequently perform preliminary short-duration MD simulations of 296 waters solvating Cu/Zn-SOD. Six representative geometries are selected and energy-minimized. Single-point SIBFA and QM computations are then performed in parallel on model binding sites extracted from these six structures, each of which totals 301 atoms including the closest 28 waters from the Cu metal site. The ranking of their relative stabilities as given by SIBFA is identical to the QM one, and the relative energy differences by both approaches are fully consistent. In addition, the lowest-energy structure, from SIBFA and QM, has a close overlap with the crystallographic one. The SIBFA calculations enable to quantify the impact of polarization and charge transfer in the ranking of the six structures. Five structural waters, which connect Arg141 and Glu131, are endowed with very high dipole moments (2.7-3.0 Debye), equal and larger than the one computed by SIBFA in ice-like arrangements (2.7 D). |
BibTeX:
@article{ISI:000342747100002,
author = {Gresh, Nohad and El Hage, Krystel and Perahia, David and Piquemal, Jean-Philip and Berthomieu, Catherine and Berthomieu, Dorothee},
title = {Polarizable Molecular Mechanics Studies of Cu(I)/Zn(II) Superoxide Dismutase: Bimetallic Binding Site and Structured Waters},
journal = {JOURNAL OF COMPUTATIONAL CHEMISTRY},
year = {2014},
volume = {35},
number = {29},
pages = {2096-2106},
doi = {10.1002/jcc.23724}
}
|
| "Characterization of Nuclear Materials in Extreme Conditions: Raman Spectroscopy Approach" Guimbretiere G, Desgranges L, Jegou C, Canizares A, Simon P, Caraballo R, Raimboux N, Barthe M-F, Ammar M-R, Maslova OA, Duval F and Omnee R, IEEE TRANSACTIONS ON NUCLEAR SCIENCE., AUG, {2014}. Vol. {61}({4, 2}), pp. {2045-2051}. (2014). |
| Abstract: A review is given of our last advances on Raman spectroscopy characterization of irradiated and/or leached UO2, PuO2 and (U, Pu)O-2 samples. For this purpose, three original Raman setups dedicated to the study of nuclear materials were involved. In every case, irradiation-induced Raman defect bands in the 500-750 cm(-1) range was observed. For UO2, an annealing temperature experiment suggests that these defect bands could be the signatures of medium-range structured defects. Besides, the leaching experiments show different behavior between the irradiated in situ probed UO2 ceramic and post mortem probed [UO2 + (U, Pu)O-2] sample: The growth of an altered layer made of studtite and schoepite phases was monitored at the surface of UO2 ceramic, while post-mortem studies reveal the presence of U3O8 and studtite phases at the surface of the UO2 grains of the binary sample. No alteration layer was observed at the surface of the leached (U, Pu)O-2 grains. |
BibTeX:
@article{ISI:000343929400013,
author = {Guimbretiere, G. and Desgranges, L. and Jegou, C. and Canizares, A. and Simon, P. and Caraballo, R. and Raimboux, N. and Barthe, M-F and Ammar, M-R and Maslova, O. A. and Duval, F. and Omnee, R.},
title = {Characterization of Nuclear Materials in Extreme Conditions: Raman Spectroscopy Approach},
journal = {IEEE TRANSACTIONS ON NUCLEAR SCIENCE},
year = {2014},
volume = {61},
number = {4, 2},
pages = {2045-2051},
doi = {10.1109/TNS.2014.2311166}
}
|
| "Diffusion-controlled reactions modeling in Geant4-DNA" Karamitros M, Luan S, Bernal MA, Allison J, Baldacchino G, Davidkova M, Francis Z, Friedland W, Ivantchenko V, Ivantchenko A, Mantero A, Nieminem P, Santin G, Tran HN, Stepan V and Incerti S, JOURNAL OF COMPUTATIONAL PHYSICS., OCT 1, {2014}. Vol. {274}, pp. {841-882}. (2014). |
| Abstract: Context Under irradiation, a biological system undergoes a cascade of chemical reactions that can lead to an alteration of its normal operation. There are different types of radiation and many competing reactions. As a result the kinetics of chemical species is extremely complex. The simulation becomes then a powerful tool which, by describing the basic principles of chemical reactions, can reveal the dynamics of the macroscopic system. To understand the dynamics of biological systems under radiation, since the 80s there have been on-going efforts carried out by several research groups to establish a mechanistic model that consists in describing all the physical, chemical and biological phenomena following the irradiation of single cells. This approach is generally divided into a succession of stages that follow each other in time: (1) the physical stage, where the ionizing particles interact directly with the biological material; (2) the physico-chemical stage, where the targeted molecules release their energy by dissociating, creating new chemical species; (3) the chemical stage, where the new chemical species interact with each other or with the biomolecules; (4) the biological stage, where the repairing mechanisms of the cell come into play. This article focuses on the modeling of the chemical stage. Method This article presents a general method of speeding-up chemical reaction simulations in fluids based on the Smoluchowski equation and Monte-Carlo methods, where all molecules are explicitly simulated and the solvent is treated as a continuum. The model describes diffusion-controlled reactions. This method has been implemented in Geant4-DNA. The keys to the new algorithm include: (I) the combination of a method to compute time steps dynamically with a Brownian bridge process to account for chemical reactions, which avoids costly fixed time step simulations; (2) a k-d tree data structure for quickly locating, for a given molecule, its closest reactants. The performance advantage is presented in terms of complexity, and the accuracy of the new algorithm is demonstrated by simulating radiation chemistry in the context of the Geant4-DNA project. Application The time-dependent radiolytic yields of the main chemical species formed after irradiation are computed for incident protons at different energies (from 50 MeV to 500 key). Both the time-evolution and energy dependency of the yields are discussed. The evolution, at one microsecond, of the yields of hydroxyls and solvated electrons with respect to the linear energy transfer is compared to theoretical and experimental data. According to our results, at high linear energy transfer, modeling radiation chemistry in the trading compartment representation might be adopted. (C) 2014 Elsevier Inc. All rights reserved. |
BibTeX:
@article{ISI:000340335800044,
author = {Karamitros, M. and Luan, S. and Bernal, M. A. and Allison, J. and Baldacchino, G. and Davidkova, M. and Francis, Z. and Friedland, W. and Ivantchenko, V. and Ivantchenko, A. and Mantero, A. and Nieminem, P. and Santin, G. and Tran, H. N. and Stepan, V. and Incerti, S.},
title = {Diffusion-controlled reactions modeling in Geant4-DNA},
journal = {JOURNAL OF COMPUTATIONAL PHYSICS},
year = {2014},
volume = {274},
pages = {841-882},
doi = {10.1016/j.jcp.2014.06.011}
}
|
| "Radiolysis of water in the vicinity of passive surfaces" Moreau S, Fenart M and Renault JP, CORROSION SCIENCE., JUN, {2014}. Vol. {83}, pp. {255-260}. (2014). |
| Abstract: Porous metals were used to describe the water radiolysis in the vicinity of metal surfaces. The hydroxyl radical production under gamma irradiation was measured by benzoate scavenging in water confined in a 200 nm porous Ni base alloy or in Stainless steel. The presence of the metallic surfaces changed drastically the HOo production level and lifetime. The solvated electron production was measured via glycylglycine scavenging for Stainless steel and was found to be significantly smaller than hydroxyl production. These observations imply that interfacial radiolysis may deeply impact the corrosion behavior of the SS and Ni based alloys. (C) 2014 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000335274700026,
author = {Moreau, S. and Fenart, M. and Renault, J. P.},
title = {Radiolysis of water in the vicinity of passive surfaces},
journal = {CORROSION SCIENCE},
year = {2014},
volume = {83},
pages = {255-260},
doi = {10.1016/j.corsci.2014.02.024}
}
|
| "Influence of hydrogen-oxidizing bacteria on the corrosion of low carbon steel: Local electrochemical investigations" Moreira R, Schuetz MK, Libert M, Tribollet B and Vivier V , BIOELECTROCHEMISTRY., JUN, {2014}. Vol. {97}({SI}), pp. {69-75}. (2014). |
| Abstract: Low carbon steel has been considered a suitable material for component of the multi-barrier system employed on the geological disposal of high-level radioactive waste (HLW). A non negligible amount of dihydrogen (H-2) is expected to be produced over the years within the geological repository due to the anoxic corrosion of metallic materials and also to the water radiolysis. The influence of the activity of hydrogen-oxidizing bacteria (HOB) and iron-reducing bacteria (IRB) on carbon steel corrosion is considered in this study because of the high availability of energetic nutriments (H-2, iron oxides and hydroxides) produced in anoxic disposal conditions. Local electrochemical techniques were used for investigating the activity of IRB as a promoter of local corrosion in the presence of H-2 as electron donor. A local consumption of H2 by the bacteria has been evidenced and impedance measurements indicate the formation of a thick layer of corrosion products. (C) 2013 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000334083300010,
author = {Moreira, Rebeca and Schuetz, Marta K. and Libert, Marie and Tribollet, Bernard and Vivier, Vincent},
title = {Influence of hydrogen-oxidizing bacteria on the corrosion of low carbon steel: Local electrochemical investigations},
journal = {BIOELECTROCHEMISTRY},
year = {2014},
volume = {97},
number = {SI},
pages = {69-75},
doi = {10.1016/j.bioelechem.2013.10.003}
}
|
| "Comparison of UV and high-energy ion irradiation of methanol:ammonia ice" Munoz Caro GM, Dartois E, Boduch P, Rothard H, Domaracka A and Jimenez-Escobar A, ASTRONOMY & ASTROPHYSICS., JUN, {2014}. Vol. {566}, (2014). |
| Abstract: Aims. The main goal of this work is to compare the effects induced in ices of astrophysical relevance by high-energy ions, simulating cosmic rays, and by vacuum ultraviolet (UV) photons. Methods. This comparison relies on in situ infrared spectroscopy of irradiated CH3OH: NH3 ice. Swift heavy ions were provided by the GANIL accelerator. The source of UV was a microwave-stimulated hydrogen flow discharge lamp. The deposited energy doses were similar for ion beams and UV photons to allow a direct comparison. Results. A variety of organic species was detected during irradiation and later during ice warm-up. These products are common to ion and UV irradiation for doses up to a few tens of eV per molecule. Only the relative abundance of the CO product, after ice irradiation, was clearly higher in the ion irradiation experiments. Conclusions. For some ice mixture compositions, the irradiation products formed depend only weakly on the type of irradiation, swift heavy ions, or UV photons. This simplifies the chemical modeling of energetic ice processing in space. |
BibTeX:
@article{ISI:000338681500051,
author = {Munoz Caro, G. M. and Dartois, E. and Boduch, P. and Rothard, H. and Domaracka, A. and Jimenez-Escobar, A.},
title = {Comparison of UV and high-energy ion irradiation of methanol:ammonia ice},
journal = {ASTRONOMY & ASTROPHYSICS},
year = {2014},
volume = {566},
doi = {10.1051/0004-6361/201322983}
}
|
| "Radiolysis of amino acids by heavy and energetic cosmic ray analogues in simulated space environments: alpha-glycine zwitterion form" Portugal W, Pilling S, Boduch P, Rothard H and Andrade DPP, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY., JUL 11, {2014}. Vol. {441}({4}), pp. {3209-3225}. (2014). |
| Abstract: In this work, we studied the stability of the glycine molecule in the crystalline zwitterion form, known as alpha-glycine (+NH3CH2COO-), under the action of heavy cosmic ray analogues. The experiments were conducted in a high vacuum chamber at the heavy-ion accelerator Grand Acc,l,rateur National d'Ions Lourds (GANIL), in Caen, France. The samples were bombarded at two temperatures (14 and 300 K) by Ni-58(11+) ions of 46 MeV, up to a final fluence of 10(13) ion cm(-2). The chemical evolution of the sample was evaluated in situ using a Fourier Transform Infrared Spectrometer (FTIR). The bombardment at 14 K produced several daughter species, such as OCN-, CO, CO2 and CN-. The results also suggest the appearance of peptide bonds during irradiation, but this must be confirmed by further experiments. The half-life of glycine in the interstellar medium was estimated to be 7.8 x 10(3) yr (300 K) and 2.8 x 10(3) yr (14 K). In the Solar system, the values were 8.4 x 10(2) yr (300 K) and 3.6 x 10(3) yr (14 K). It is believed that glycine could be present in space environments that suffered aqueous changes, such as the interiors of comets, meteorites and planetesimals. This molecule is present in the proteins of all living beings. Therefore, studying its stability in these environments will provide further understanding of the role of this species in prebiotic chemistry on Earth. |
BibTeX:
@article{ISI:000338764700030,
author = {Portugal, Williamary and Pilling, Sergio and Boduch, Philippe and Rothard, Hermann and Andrade, Diana P. P.},
title = {Radiolysis of amino acids by heavy and energetic cosmic ray analogues in simulated space environments: alpha-glycine zwitterion form},
journal = {MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
year = {2014},
volume = {441},
number = {4},
pages = {3209-3225},
doi = {10.1093/mnras/stu656}
}
|
| "Implementation of laser induced fluorescence in a pulse radiolysis experiment - a new way to analyze resazurin-like reduction mechanisms" Balcerzyk A and Baldacchino G, ANALYST. Vol. {139}({7}), pp. {1707-1712}. (2014). |
| Abstract: Resazurin (RNO) reduction by hydrated electrons produces a fluorescent molecule: resorufin (RN). To take advantage of RN fluorescence, a novel setup is designed by implementing fluorescence detection induced by laser in a pulse radiolysis experiment. Time resolved fluorescence spectra were recorded with a fast gated intensified CCD camera during the reduction of RNO from mu s to ms. Two 532 nm laser types have been used to describe the short ms range by a 5 ns Q-switch laser and the mu s-ms range by a CW DPSS laser. By fitting the simulated model to the experimental data a second order rate constant of 10(9) M-1 s(-1) was re-evaluated. This method should be considered in the near future in many in situ and real time measurements for evaluating radical production. |
BibTeX:
@article{ISI:000332422400018,
author = {Balcerzyk, A. and Baldacchino, G.},
title = {Implementation of laser induced fluorescence in a pulse radiolysis experiment - a new way to analyze resazurin-like reduction mechanisms},
journal = {ANALYST},
year = {2014},
volume = {139},
number = {7},
pages = {1707-1712},
doi = {10.1039/c3an02000b}
}
|
| "Processing of formic acid-containing ice by heavy and energetic cosmic ray analogues" Bergantini A, Pilling S, Rothard H, Boduch P and Andrade DPP, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY., JAN, {2014}. Vol. {437}({3}), pp. {2720-2727}. (2014). |
| Abstract: Formic acid (HCOOH) has been extensively detected in space environments, including interstellar medium (gas and grains), comets and meteorites. Such environments are often subjected to the action of ionizing agents, which may cause changes in the molecular structure, thus leading to formation of new species. Formic acid is a possible precursor of pre-biotic species, such as Glycine (NH2CH2COOH). This work investigates experimentally the physicochemical effects resulting from interaction of heavy and energetic cosmic ray analogues (46 MeV Ni-58(11 +)) in H2O:HCOOH (1:1) ice, at 15 K, in ultrahigh vacuum regime, using Fourier transform infrared spectrometry in the mid-infrared region (4000-600 cm(-1) or 2.5-12.5 mu m). After the bombardment, the sample was slowly heated to room temperature. The results show the dissociation cross-section for the formic acid of 2.4 x 10(-13) cm(2), and half-life due to galactic cosmic rays of similar to 8 x 10(7) yr. The IR spectra show intense formation of CO and CO2, and small production of more complex species at high fluences. |
BibTeX:
@article{ISI:000329158900053,
author = {Bergantini, A. and Pilling, S. and Rothard, H. and Boduch, P. and Andrade, D. P. P.},
title = {Processing of formic acid-containing ice by heavy and energetic cosmic ray analogues},
journal = {MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
year = {2014},
volume = {437},
number = {3},
pages = {2720-2727},
doi = {10.1093/mnras/stt2082}
}
|
| "Effect of hydration and thermal treatment on ceria surface using non-intrusive techniques" Gaillard J, Venault L, Calvet R, Del Confetto S, Clavier N, Podor R, Odorico M, Pellequer J-L, Vigier N and Moisy P, JOURNAL OF NUCLEAR MATERIALS., JAN, {2014}. Vol. {444}({1-3}), pp. {359-367}. (2014). |
| Abstract: The evolution of plutonium dioxide surface due to water adsorption seems to influence H-2 generation through the radiolysis of adsorbed water. Surface evolution of ceria, a non-radioactive surrogate for plutonium dioxide, was investigated using Inverse Gas Chromatography (IGC), Raman spectroscopy, Environmental Scanning Electronic Microscopy (ESEM) and Atomic Force Microscopy (AFM). IGC highlights the complexity of ceria surface revealing three different adsorption sites on surface and indicate a surface evolution upon hydration. Thermal treatment appears to regenerate at least partially the initial surface state before hydration. IGC points out the influence of calcination temperature of ceria precursor on surface reactivity. The nature of surface modification was investigated by Raman spectroscopy which suggests formation of superficial hydroxide layer. ESEM and AFM were used to study potential surface topology modification upon superficial layer formation. Cerium hydroxide forms as a superficial layer with a nanostructure differing from the one of the oxide. (C) 2013 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000329888100046,
author = {Gaillard, Jeremy and Venault, Laurent and Calvet, Rachel and Del Confetto, Sylvie and Clavier, Nicolas and Podor, Renaud and Odorico, Michael and Pellequer, Jean-Luc and Vigier, Nicolas and Moisy, Philippe},
title = {Effect of hydration and thermal treatment on ceria surface using non-intrusive techniques},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2014},
volume = {444},
number = {1-3},
pages = {359-367},
doi = {10.1016/j.jnucmat.2013.10.018}
}
|
| 2013 |
| "Chemical reactions induced in frozen formic acid by heavy ion cosmic rays" Andrade DPP, de Barros ALF, Pilling S, Domaracka A, Rothard H, Boduch P and da Silveira EF, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY., APR, {2013}. Vol. {430}({2}), pp. {787-796}. (2013). |
| Abstract: We studied the effects produced by the interaction of heavy ion cosmic rays with interstellar and cometary organic molecules in the solid phase. Formic acid (HCOOH) ice at 15 K was irradiated by 267-MeV Fe-56(22+) ions and the chemical evolution was analysed using Fourier transform infrared spectroscopy. The destruction cross-section of HCOOH and the formation cross-sections of the produced molecular species have been determined; the sputtering yield values are also discussed. The most abundant chemical species formed by Fe ion irradiation are CO, CO2 and H2O. The half-life of frozen formic acid molecules in the interstellar medium, as a result of interaction with the different cosmic ray constituents, is evaluated to be 10(8) yr, considering that the destruction cross-section sigma(d) of heavy ions is ruled by a power law as a function of the electronic stopping power S-e (i.e. sigma(d) similar to S-e(3/2)). Moreover, a complementary study based on mass spectrometry data from the literature has been performed, in order to understand the HCOOH molecule radiolysis, the desorption of its product and the chemical reaction pathways in ice. |
BibTeX:
@article{ISI:000318275000004,
author = {Andrade, Diana P. P. and de Barros, Ana L. F. and Pilling, Sergio and Domaracka, Alicja and Rothard, Hermann and Boduch, Philippe and da Silveira, Enio F.},
title = {Chemical reactions induced in frozen formic acid by heavy ion cosmic rays},
journal = {MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
year = {2013},
volume = {430},
number = {2},
pages = {787-796},
doi = {10.1093/mnras/sts408}
}
|
| "CHEMICAL PROCESSING OF PURE AMMONIA AND AMMONIA-WATER ICES INDUCED BY HEAVY IONS" Bordalo V, da Silveira EF, Lv XY, Domaracka A, Rothard H, Seperuelo Duarte E and Boduch P , ASTROPHYSICAL JOURNAL., SEP 10, {2013}. Vol. {774}({2}), (2013). |
| Abstract: Cosmic rays are possibly the main agents to prevent the freeze-out of molecules onto grain surfaces in cold dense clouds. Ammonia (NH3) is one of the most abundant molecules present in dust ice mantles, with a concentration of up to 15% relative to water (H2O). FTIR spectroscopy is used to monitor pure NH3 and NH3-H2O ice samples as they are irradiated with Ni and Zn ion beams (500-600 MeV) at GANIL/France. New species, such as hydrazine (N2H4), diazene (N2H2 isomers), molecular hydrogen (H-2), and nitrogen (N-2) were identified after irradiation of pure NH3 ices. Nitrous oxide (N2O), nitrogen oxide (NO), nitrogen dioxide (NO2), and hydroxylamine (NH2OH) are some of the products of the NH3-H2O ice radiolysis. The spectral band at 6.85 mu m was observed after irradiation of both types of ice. Besides the likely contribution of ammonium (NH4+) and amino (NH2) radicals, data suggest a small contribution of NH2OH to this band profile after high fluences of irradiation of NH3-H2O ices. The spectral shift of the NH3 ``umbrella'' mode (9.3 mu m) band is parameterized as a function of NH3/H2O ratio in amorphous ices. Ammonia and water destruction cross-sections are obtained, as well as the rate of NH3-H2O (1:10) ice compaction, measured by the OH dangling bond destruction cross-section. Ammonia destruction is enhanced in the presence of H2O in the ice and a power law relationship between stopping power and NH3 destruction cross-section is verified. Such results may provide relevant information for the evolution of molecular species in dense molecular clouds. |
BibTeX:
@article{ISI:000323888900014,
author = {Bordalo, V. and da Silveira, E. F. and Lv, X. Y. and Domaracka, A. and Rothard, H. and Seperuelo Duarte, E. and Boduch, P.},
title = {CHEMICAL PROCESSING OF PURE AMMONIA AND AMMONIA-WATER ICES INDUCED BY HEAVY IONS},
journal = {ASTROPHYSICAL JOURNAL},
year = {2013},
volume = {774},
number = {2},
doi = {10.1088/0004-637X/774/2/105}
}
|
| "Experimental evidence of the influence of iron on pore water radiolysis in cement-based materials" Bouniol P, Muzeau B and Dauvois V, JOURNAL OF NUCLEAR MATERIALS., JUN, {2013}. Vol. {437}({1-3}), pp. {208-215}. (2013). |
| Abstract: Hydrated tricalcium silicate based cement pastes or mixes, with the addition or not of amorphous iron oxyhydroxide, were irradiated for I year in a closed system (7 radiation) with the aim of provoking radiolysis of the alkaline pore solution (pH > 13). The data collected (on-line monitoring of the total pressure and the H-2 content in 500 cm(3) mini-containers irradiated at 45 degrees C and 1.07 kGy/h with V-gas/V-paste approximate to 1) enable us to conclude that the addition of 1% of FeOOHam, gives rise to about 26% of additional residual H-2 after 1 year. This result appears to validate the hypothesis of a partial mobilisation of the and O- radicals in a continuous process of Fe(III) <-> Fe(II) oxidation-reduction, at the expense of their action within the Allen type reaction chain that is responsible for the recycling of H-2. Despite the complexity of the porous material, the simulation of the experiment with the CHEMSIMUL application leads to a result that is quite close, and stresses the importance of the kinetic coupling between gas transport in the porous material and the reaction system. (C) 2013 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000319172200032,
author = {Bouniol, P. and Muzeau, B. and Dauvois, V.},
title = {Experimental evidence of the influence of iron on pore water radiolysis in cement-based materials},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2013},
volume = {437},
number = {1-3},
pages = {208-215},
doi = {10.1016/j.jnucmat.2013.02.018}
}
|
| "Response to Comment on ``Mechanism of Pt-IV Sonochemical Reduction in Formic Acid Media and Pure Water''" |
| Abstract: Contrary to radiolysis, sonochemistry is not only based on radical processes and further effects such as local activation or heating must be considered in particular for the sonolysis of formic acid. In the same way, the high local concentration of radicals observed in sonochemistry can induce different mechanisms compared to radiolysis. |
BibTeX:
@article{ISI:000327801800044,
author = {Chave, Tony and Nikitenko, Sergey I.},
title = {Response to Comment on ``Mechanism of Pt-IV Sonochemical Reduction in Formic Acid Media and Pure Water''},
journal = {CHEMISTRY-A EUROPEAN JOURNAL},
year = {2013},
volume = {19},
number = {50},
pages = {17213-17215},
doi = {10.1002/chem.201303042}
}
|
| "Implantation of multiply charged sulfur ions in water ice" Ding JJ, Boduch P, Domaracka A, Guillous S, Langlinay T, Lv XY, Palumbo ME, Rothard H and Strazzulla G, ICARUS., SEP-OCT, {2013}. Vol. {226}({1}), pp. {860-864}. (2013). |
| Abstract: Sulfuric acid has been suggested to be present on the surface of the jovian moon Europa where it is mixed with the dominant water ice. The formation mechanism of sulfuric acid is still under discussion. We present new experimental results on the implantation of Sq+ (q = 7, 9, 11) ions at an energy range between 35 and 176 keV in water ice at 80 K. Previous results on 200 keV S+ implantation in H2O at 80K have also been included in the data analysis. Experiments with multiply-charged ions at different energies are particularly relevant to simulate the complexity of the irradiation environment to which the surface of Europa is exposed being embedded in the jovian magnetosphere. The experiments were performed at the low energy ion beam facility ARIBE of GANIL in Caen (France). 35-176 key Sq(+) (q = 7, 9, 11) ions were implanted in solid H2O layers which were frozen at 80K. Fowler Transform Infrared Spectrometry (FTIR) was used to analyze the sample in the 5000-600 cm(-1) (2-16.7 mu m) region with a spectral resolution of 1 cm(-1). The results of our experiments indicate that implantation produces hydrated sulfuric acid with yields that increase with ion energy, from 0.12 molecules ion(-1) for 35 key ions to 0.64 molecules ion(-1) for 200 key ions. We have also searched for the production of SO2 and H2S, but we were not able to find any evidence for their synthesis. We conclude that sulfur ion implantation is the dominant formation mechanism of hydrated sulfuric acid at Europa. The suggestion that the observed distribution of sulfuric acid on the surface is well correlated with the local flux of sulfur ions find a full explanation by present experimental data. (C) 2013 Elsevier Inc. All rights reserved. |
BibTeX:
@article{ISI:000324720200066,
author = {Ding, J. J. and Boduch, P. and Domaracka, A. and Guillous, S. and Langlinay, T. and Lv, X. Y. and Palumbo, M. E. and Rothard, H. and Strazzulla, G.},
title = {Implantation of multiply charged sulfur ions in water ice},
journal = {ICARUS},
year = {2013},
volume = {226},
number = {1},
pages = {860-864},
doi = {10.1016/j.icarus.2013.07.002}
}
|
| "Aliphatic/Aromatic Systems under Irradiation: Influence of the Irradiation Temperature and of the Molecular Organization" Ferry M, Bessy E, Harris H, Lutz PJ, Ramillon JM, Ngono-Ravache Y and Balanzat E, JOURNAL OF PHYSICAL CHEMISTRY B., NOV 21, {2013}. Vol. {117}({46}), pp. {14497-14508}. (2013). |
| Abstract: With the aim of understanding the electronic excitation, charge or reactive species transfers occurring during irradiation, we studied the role of the aromatic content on ethylene/styrene random copolymers (PES) and on cyclohexane/benzene glasses (amorphous organic solids). Radiation-induced modifications were monitored in situ, at the molecular level, using Fourier transform infrared spectroscopy (FTIR). Irradiations were performed under a vacuum, and thanks to in situ measurements, oxidation was avoided. We followed both the C = C bond creation in the aliphatic moiety and the destruction of the aromatic moiety. The influence of the irradiation temperature was investigated by irradiating samples at room temperature and at 11 K. At such a low temperature, long-range migration hardly occurs and its influence is considerably reduced or could even vanish. Therefore, low temperature irradiation gives insight on the relative influence of reactive species transport and electronic excitation and charge transport. We found that the effect of lowering the PES irradiation temperature from room temperature to 11 K is small, indicating a minor role for the reactive species transport. Moreover, the two chosen systems allow the examination of the relative magnitude of intra- and intermolecular transfers. We demonstrate that, under conditions where reactive species are almost frozen, intermolecular transfers are very efficient. |
BibTeX:
@article{ISI:000327557700033,
author = {Ferry, M. and Bessy, E. and Harris, H. and Lutz, P. J. and Ramillon, J. -M. and Ngono-Ravache, Y. and Balanzat, E.},
title = {Aliphatic/Aromatic Systems under Irradiation: Influence of the Irradiation Temperature and of the Molecular Organization},
journal = {JOURNAL OF PHYSICAL CHEMISTRY B},
year = {2013},
volume = {117},
number = {46},
pages = {14497-14508},
doi = {10.1021/jp406260z}
}
|
| "Water Radiolysis in Exchanged-Montmorillonites: The H-2 Production Mechanisms" Fourdrin C, Aarrachi H, Latrille C, Esnouf S, Bergaya F and Le Caer S, ENVIRONMENTAL SCIENCE & TECHNOLOGY., AUG 20, {2013}. Vol. {47}({16}), pp. {9530-9537}, (2013). |
| Abstract: The radiolysis of water confined in montmorillonites is studied as a function of the composition of the montrnorillonite, the nature of the exchangeable cation, and the relative humidity by following the H-2 production under electron irradiation. It is shown that the main factor influencing this H-2 production is the water amount in the interlayer space. The effect of the exchangeable cation is linked to its hydration enthalpy. When the water amount is high enough to get a basal distance higher than 1.3 nm, then a total energy transfer from the montmorillonite sheets to the interlayer space occurs, and the H-2 production measured is very similar to the one obtained in bulk water. For a basal distance smaller than 1.3 nm, the H-2 production increases with the relative humidity and thus with the water amount. Lastly, electron paramagnetic resonance measurements evidence the formation of a new defect induced by ionizing radiation. It consists of a hydrogen radical (H-2 precursor) trapped in the structure. This implies that structural hydroxyl bonds can be broken under irradiation, potentially accounting for the observed H-2 production. |
BibTeX:
@article{ISI:000323471700065,
author = {Fourdrin, C. and Aarrachi, H. and Latrille, C. and Esnouf, S. and Bergaya, F. and Le Caer, S.},
title = {Water Radiolysis in Exchanged-Montmorillonites: The H-2 Production Mechanisms},
journal = {ENVIRONMENTAL SCIENCE & TECHNOLOGY},
year = {2013},
volume = {47},
number = {16},
pages = {9530-9537},
doi = {10.1021/es401490t}
}
|
| "In situ Raman monitoring of He2+ irradiation induced damage in a UO2 ceramic" Guimbretiere G, Desgranges L, Canizares A, Caraballo R, Duval F, Raimboux N, Omnee R, Ammar MR, Jegou C and Simon P, APPLIED PHYSICS LETTERS., JUL 22, {2013}. Vol. {103}({4}), (2013). |
| Abstract: The in situ Raman probing of a UO2 ceramic in [Ar/H-2, 95/5] gas atmosphere followed by exposure to He2+ ionic irradiation coming from a cyclotron accelerator was implemented. It was observed that the growth of Raman defect bands exhibits a unique kinetic nicely modelized by a simple direct impact model, and with an annealing rate constant of 5.6 x 10(-4) +/- 4 x 10(-5) s(-1) for an ionic flow of 50 nA and an ions-beam induced sample heating of 170 +/- 10 degrees C. Also, it was observed that the Ar plasma induced by the ions-beam is a sensitive probe of the presence of the ions-beam. (C) 2013 AIP Publishing LLC. |
BibTeX:
@article{ISI:000322406600031,
author = {Guimbretiere, G. and Desgranges, L. and Canizares, A. and Caraballo, R. and Duval, F. and Raimboux, N. and Omnee, R. and Ammar, M. R. and Jegou, C. and Simon, P.},
title = {In situ Raman monitoring of He2+ irradiation induced damage in a UO2 ceramic},
journal = {APPLIED PHYSICS LETTERS},
year = {2013},
volume = {103},
number = {4},
doi = {10.1063/1.4816285}
}
|
| "Formation of negative hydrogen ions in 7-keV OH++ Ar and OH++ acetone collisions: A general process for H-bearing molecular species" Juhasz Z, Sulik B, Rangama J, Bene E, Sorgunlu-Frankland B, Fremont F and Chesnel J-Y, PHYSICAL REVIEW A., MAR 29, {2013}. Vol. {87}({3}), (2013). |
| Abstract: We demonstrate that the formation of negative hydrogen ions (H-) occurs in a wide class of atomic and molecular collisions. In our experiments, H(-)emission from hydroxyl cations and acetone molecules was observed in keV-energy collisions. We show that hydride (H-) anions are formed via direct collisional fragmentation of molecules, followed by electron grabbing by fast hydrogen fragments. Such general mechanism in hydrogen-containing molecules may significantly influence reaction networks in planetary atmospheres and astrophysical media and new reaction pathways may have to be added in radiolysis studies. DOI: 10.1103/PhysRevA.87.032718 |
BibTeX:
@article{ISI:000316931600008,
author = {Juhasz, Zoltan and Sulik, Bela and Rangama, Jimmy and Bene, Erika and Sorgunlu-Frankland, Burcu and Fremont, Francois and Chesnel, Jean-Yves},
title = {Formation of negative hydrogen ions in 7-keV OH++ Ar and OH++ acetone collisions: A general process for H-bearing molecular species},
journal = {PHYSICAL REVIEW A},
year = {2013},
volume = {87},
number = {3},
doi = {10.1103/PhysRevA.87.032718}
}
|
| "H-2 production through oxide irradiation: Comparison of gamma rays and vacuum ultraviolet excitation" Klett C, Cui Y, Devineau S, Foy E, Dagnelie R and Renault JP, INTERNATIONAL JOURNAL OF HYDROGEN ENERGY., APR 1, {2013}. Vol. {38}({10}), pp. {3889-3897}. (2013). |
| Abstract: The production of molecular hydrogen by gamma radiolysis and vacuum ultra violet photolysis of dried and hydrated nanoporous titania and zirconia nanoparticles has been studied. The nanoparticles were prepared as free standing films using a surface sol-gel process on cellulose. A significant hydrogen production was observed for both TiO2 and ZrO2 in vacuum ultra violet or gamma irradiation. This production could be optimized by controlling the amount of water and by introducing hydroxyl radical scavengers in the irradiated systems. The mechanism underlying hydrogen production seems qualitatively different in gamma and in vacuum ultra violet (VUV) irradiation. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000316714200007,
author = {Klett, Charles and Cui, Yanan and Devineau, Stephanie and Foy, Eddy and Dagnelie, Romain and Renault, Jean Philippe},
title = {H-2 production through oxide irradiation: Comparison of gamma rays and vacuum ultraviolet excitation},
journal = {INTERNATIONAL JOURNAL OF HYDROGEN ENERGY},
year = {2013},
volume = {38},
number = {10},
pages = {3889-3897},
doi = {10.1016/j.ijhydene.2012.12.035}
}
|
| "Water splitting by infrared femtosecond laser excitation of surface plasmon" Klett C, Mirica J-P, Hergott J-F, Lepetit F and Renault J-P, CHEMICAL PHYSICS LETTERS., FEB 12, {2013}. Vol. {558}, pp. {31-35}. (2013). |
| Abstract: Gold nanoparticles supported on soda-lime glass exhibit a photochemical water splitting activity under infrared femtosecond laser excitation. Both H-2 and hydroxyl radicals productions were characterized. The hydroxyl radicals production mechanism was identified by comparison with three prototypal mechanisms, photoionization of organic compound in the UV, VUV dissociation of water and water gamma radiolysis. The mechanisms involved in the case of laser femtosecond seem to be water ionization events occurring at distance from the gold particles. (C) 2012 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000314660600006,
author = {Klett, Charles and Mirica, Jean-Philippe and Hergott, Jean-Francois and Lepetit, Fabien and Renault, Jean-Philippe},
title = {Water splitting by infrared femtosecond laser excitation of surface plasmon},
journal = {CHEMICAL PHYSICS LETTERS},
year = {2013},
volume = {558},
pages = {31-35},
doi = {10.1016/j.cplett.2012.12.031}
}
|
| "Design of a high pressure system for pulse radiolysis studies up to 400 MPa with flow regulation" Le DTN, Pin S, Anjoure D, Chopineau P and Baldacchino G, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS., MAR 15, {2013}. Vol. {299}, pp. {1-7}. (2013). |
| Abstract: This article reports details of a new setup including an optical flow cell and devices which can increase pressure up to 400 MPa by controlling the ramp rate. It is composed of two high pressure syringe pumps which can make liquids flowing up to 4 cm(3)/mn. The optical flow cell can contains aqueous solutions and allow carry out pulse radiolysis experiments with a pulsed 10-MeV electron beam by performing in situ and time resolved optical analysis, such as transient UV-visible absorption or fluorescence spectroscopy. A Labview-program has been developed to drive and monitor automatons which regulate pressure, make solution flow under pressure, carry out operations such as filling, emptying or cleaning the system under safe conditions. Two results are exhibited: 1/associated to phosphate buffer, the fluorescence spectrum of the fluorescein pH-sensor has been performed under pressure. Phosphate pKa is confirmed to be very sensitive to pressure increase even up to 300 MPa. 2/a time-resolved absorption spectroscopy of hydrated electron in deaerated water has been conducted up to 350 MPa with a continuous flow of sample. In presence of tertio-butanol and bisTris pH7-buffer in solution, the spectral shift of hydrated electron is finely reproduced. BisTris is also confirmed as insensitive buffer under high pressure and its reduction by hydrated electron remains constant with a rate constant of (4.6 +/- 0.6) x 10(8) M-1 S-1. (C) 2013 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000317322200001,
author = {Le, D. -T. NGuyen and Pin, S. and Anjoure, D. and Chopineau, P. and Baldacchino, G.},
title = {Design of a high pressure system for pulse radiolysis studies up to 400 MPa with flow regulation},
journal = {NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS},
year = {2013},
volume = {299},
pages = {1-7},
doi = {10.1016/j.nimb.2013.01.034}
}
|
| "Influence of the Nature of Self-Assembled Mono layers on Their Reactivity under Ionizing Radiation: A Solid-State NMR Study" Le Caer S, Brunet F, Chatelain C, Ladevie L, Durand D, Dauvois V, Renault JP and Charpentier T, JOURNAL OF PHYSICAL CHEMISTRY C., NOV 7, {2013}. Vol. {117}({44}), pp. {23258-23271}. (2013). |
| Abstract: The behavior of different nanoporous grafted silicas (-Si(CH3)(2)R) under ionizing radiation is investigated as a function of the chemical nature of the grafting. The structure and reactivity of the grafting after irradiation is characterized by solid-state NMR spectroscopy. The chemical reactivity is also investigated by mass spectrometry gas analysis. The major gases detected after irradiation are H-2 and/or CH4. Different types of behaviors under ionizing radiation are depicted as a function of R When R contains an aromatic ring or is the cyclopentadienyl moiety, then the overall measured radiolytic yields are low and CH4 is the major gas detected. The aromatic ring acts as an efficient energy trap. When R contains an alkyl chain with a -CN ending, the major gas detected is dihydrogen due to the lysis of the -CH(H) bond, but it is also shown that the -CN group acts as an energy trap, even if it is of course less efficient than an aromatic ring. When R consists of a long alkyl chain, an efficient energy transfer occurs at the interface and leads to a significant H-2 production due to the lysis of the -CH(H)- bond. Lastly, when R is small (a methyl or an ethyl group), the situation is different and the Si-C bond is preferentially cleaved over the C-H bond. |
BibTeX:
@article{ISI:000326845400089,
author = {Le Caer, S. and Brunet, F. and Chatelain, C. and Ladevie, L. and Durand, D. and Dauvois, V. and Renault, J. Ph. and Charpentier, T.},
title = {Influence of the Nature of Self-Assembled Mono layers on Their Reactivity under Ionizing Radiation: A Solid-State NMR Study},
journal = {JOURNAL OF PHYSICAL CHEMISTRY C},
year = {2013},
volume = {117},
number = {44},
pages = {23258-23271},
doi = {10.1021/jp4056335}
}
|
| "Are underground clay disposal conditions favorable for microbial activity and biocorrosion?" Libert M, Kerber-Schuetz M, Esnault L and Bildstein O, In PROCEEDINGS OF THE FOURTEENTH INTERNATIONAL SYMPOSIUM ON WATER-ROCK INTERACTION, WRI 14. Vol. {7}, pp. {73-76}. (2013). |
| Abstract: The French concept for geological disposal of high-level radioactive waste is based on a multi-barrier system including metallic containers confined in a claystone layer. The main alteration vector is water coming from the host rock and triggering corrosion of metallic components. Despite extreme conditions, microorganisms can adapt and survive in these environments. Anoxic corrosion of metallic containers and water radiolysis produce H-2, which potentially represents an abundant energetic source for microbial development, especially in this type of environment containing low amounts of biodegradable organic matter. Moreover, formation of Fe(III)-bearing corrosion products such as magnetite (Fe3O4) can provide electron acceptors for microbial development. Therefore, biocorrosion studies are needed in order to investigate the activity of hydrogenotrophic bacteria able to reduce sulphates or Fe(III) from iron oxides (passive layer). These studies help in evaluating such microbial impacts on the long-term stability of metallic components involved in radioactive waste disposal. (C) 2013 The Authors. Published by Elsevier B.V. |
BibTeX:
@inproceedings{ISI:000321664000018,
author = {Libert, M. and Kerber-Schuetz, M. and Esnault, L. and Bildstein, O.},
editor = {Hellmann, R and Pitsch, H},
title = {Are underground clay disposal conditions favorable for microbial activity and biocorrosion?},
booktitle = {PROCEEDINGS OF THE FOURTEENTH INTERNATIONAL SYMPOSIUM ON WATER-ROCK INTERACTION, WRI 14},
year = {2013},
volume = {7},
pages = {73-76},
note = {14th International Symposium on Water-Rock Interaction (WRI), Avignon, FRANCE, JUN 09-14, 2013},
doi = {10.1016/j.proeps.2013.03.181}
}
|
| "Fragmentation Dynamics Of Complex Molecules And Their Clusters" Maclot S, Capron M, Maisonny R, Lawicki A, Chesnel JY, Domaracka A, Mery A, Poully JC, Rangama J, Holm AIS, Johansson HAB, Seitz F, Rosen S, Schmidt H, Zettergren H, Rousseau P, Cederquist H, Huber BA and Adoui L, In APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY. Vol. {1525}, pp. {11-19}. (2013). |
| Abstract: Complex molecular systems such as large molecules or clusters are characterised by a large number of degrees of freedom. Energies well in excess of individual thresholds for fragmentation can be stored for long times and metastable excited states become important. We will concentrate in this paper on the study of the response of such nanoscale systems, i.e. we will study excitation and fragmentation mechanisms induced by highly charged ion radiation, reflecting dynamic energy and charge flow processes. We will illustrate these relaxation processes for different molecular systems from Polycyclic Aromatic Hydrocarbons, water or biomolecule targets and their clusters in collision with multiply charged ions. We will emphasize that slow multiply charged ions provide an efficient way to study the stability of complex systems. Indeed, such ions are known to remove several electrons at large impact parameters resulting in a fast and gentle ionization. |
BibTeX:
@inproceedings{ISI:000319997900001,
author = {Maclot, S. and Capron, M. and Maisonny, R. and Lawicki, A. and Chesnel, J. -Y. and Domaracka, A. and Mery, A. and Poully, J. -C. and Rangama, J. and Holm, A. I. S. and Johansson, H. A. B. and Seitz, F. and Rosen, S. and Schmidt, H. and Zettergren, H. and Rousseau, P. and Cederquist, H. and Huber, B. A. and Adoui, L.},
editor = {McDaniel, FD and Doyle, BL and Glass, GA and Wang, Y},
title = {Fragmentation Dynamics Of Complex Molecules And Their Clusters},
booktitle = {APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY},
year = {2013},
volume = {1525},
pages = {11-19},
note = {22nd International Conference on the Application of Accelerators in Research and Industry (CAARI), Fort Worth, TX, AUG 05-10, 2012},
doi = {10.1063/1.4802280}
}
|
| "Cosmic ray-ice interaction studied by radiolysis of 15 K methane ice with MeV O, Fe and Zn ions" Mejia CF, de Barros ALF, Bordalo V, da Silveira EF, Boduch P, Domaracka A and Rothard H, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY., AUG, {2013}. Vol. {433}({3}), pp. {2368-2379}. (2013). |
| Abstract: Methane (CH4) ice is found in the interstellar medium and in several bodies of the Solar system, where it is commonly exposed to cosmic rays and stellar winds. The chemical, physical and structural effects induced by fast heavy ions in thin layers of pure CH4 ices at 15 K are analysed by mid-infrared spectroscopy (Fourier transform infrared). Different pure CH4 ice samples were irradiated with 6 MeV O-16(2 +), 220 MeV O-16(7 +), 267 MeV Fe-56(22 +) and 606 MeV Zn-70(26 +) ions at Grand Accelerateur National d'Ions Lourds/France. Results show that CnHm molecules, where n = 2-4 and m = 2(n - 1) to 2(n + 1) and radical species CH3, C2H3 and C2H5 are formed. The destruction cross-sections of CH4 ice and the formation cross-sections of new molecules CnHm are reported. The extrapolation of current results allow us to estimate the half lives of CH4 ices in the interstellar medium and the Solar system (Earth orbit) as about 600 x 10(6) and 600 yr, respectively. This huge ratio strongly suggests that the vast majority of chemical or even biochemical processes induced by ionizing radiation occur close to stars. |
BibTeX:
@article{ISI:000322403800050,
author = {Mejia, C. F. and de Barros, A. L. F. and Bordalo, V. and da Silveira, E. F. and Boduch, P. and Domaracka, A. and Rothard, H.},
title = {Cosmic ray-ice interaction studied by radiolysis of 15 K methane ice with MeV O, Fe and Zn ions},
journal = {MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
year = {2013},
volume = {433},
number = {3},
pages = {2368-2379},
doi = {10.1093/mnras/stt902}
}
|
| "Rheological, structural and chemical evolution of bitumen under gamma irradiation" Mouazen M, Poulesquen A, Bart F, Masson J, Charlot M and Vergnes B, FUEL PROCESSING TECHNOLOGY., OCT, {2013}. Vol. {114}, pp. {144-153}. (2013). |
| Abstract: Bitumen derived from crude oil by fractional distillation has been used in the nuclear industry as a radioactive waste encapsulation matrix. When subjected to alpha, beta and gamma self-irradiation, this organic matrix undergoes radiolysis, generating hydrogen bubbles and modifying the physical and chemical properties of the material. In this paper, the effects of irradiation on bitumen materials, especially in terms of its physical, chemical, structural and rheological properties, were characterized at radiation doses ranging from 1 to 7 MGy. An increase in the shear viscosity and melt yield stress was observed with increasing doses. Similarly, the elastic and viscous moduli (G' and G `') increase with the dose, with a more pronounced increase for G' that reflects enhanced elasticity arising from radiation-induced cross-linking. In addition, a low-frequency plateau is observed for G', reflecting pseudo-solid behavior and leading to an increase of the complex viscosity. This behavior is due to increased interactions between asphaltene particles, and to aromatization of the bitumen by gamma-radiations. Cross-linking of bitumen enhances its strength, as confirmed by various techniques (modulated DSC, DTA/TGA, SEC, FTIR and XRD). (C) 2013 Published by Elsevier B.V. |
BibTeX:
@article{ISI:000321089800017,
author = {Mouazen, M. and Poulesquen, A. and Bart, F. and Masson, J. and Charlot, M. and Vergnes, B.},
title = {Rheological, structural and chemical evolution of bitumen under gamma irradiation},
journal = {FUEL PROCESSING TECHNOLOGY},
year = {2013},
volume = {114},
pages = {144-153},
doi = {10.1016/j.fuproc.2013.03.039}
}
|
| "Influence of gamma irradiation effects on the residual alteration rate of the French SON68 nuclear glass" Rolland S, Tribet M, Jollivet P, Jegou C, Broudic V, Marques C, Ooms H and Toulhoat P, JOURNAL OF NUCLEAR MATERIALS., FEB, {2013}. Vol. {433}({1-3}), pp. {382-389}. (2013). |
| Abstract: The residual rate regime of SON68 nuclear glass has been investigated here by static experiments under external irradiation. The experiments were carried out in a gamma irradiator with Co-60 sources. Four dose rates were studied: two high dose rates (5 and 10 kGy h(-1)) to exacerbate electronic radiation effects, and two lower dose rates (0.8 and 0.05 kGy h(-1)). The objective of this work is not to assess potential LET effects but to assess more widely electronic effects on the residual rate regime which controls the long term stability of the glass under geological disposal. Fresh glasses were leached in argon atmosphere at 90 degrees C and at a high surface-area-to-volume ratio (SA/V = 10 000 m(-1)). Under these conditions the system quickly reaches the residual alteration rate regime. The alteration rate was monitored by solution analyses: the release of glass alteration tracer elements-in particular boron, sodium and lithium-was measured by ICP-AES. The hydrogen peroxide produced by water radiolysis was quantified by chemiluminescence. Radiation effects on the glass and its gel network were characterized by scanning electron microscopy (SEM) and Transmission Electron Microscopy (TEM). Higher H2O2 concentrations were measured on irradiated samples in the presence of glass, suggesting an irradiation effect on the glass and its alteration layer. However, the data obtained on glass alteration show that potential defects or changes induced by gamma irradiation do not modify the kinetics of alteration up to a gamma dose rate of 10 kGy h(-1): the residual rates measured for the different dose rates studied are similar and comparable to experiments performed without irradiation. Moreover, these observations are consistent with SEM and TEM characterizations which show that the alteration layer formed under gamma irradiation is similar to the alteration layer formed without irradiation. This study demonstrates that species produced by pure water radiolysis and defects induced by gamma irradiation in the glass and/or its alteration layer may remain limited and localized enough not to affect glass alteration under these conditions. (c) 2012 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000316153800049,
author = {Rolland, S. and Tribet, M. and Jollivet, P. and Jegou, C. and Broudic, V. and Marques, C. and Ooms, H. and Toulhoat, P.},
title = {Influence of gamma irradiation effects on the residual alteration rate of the French SON68 nuclear glass},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2013},
volume = {433},
number = {1-3},
pages = {382-389},
doi = {10.1016/j.jnucmat.2012.10.001}
}
|
| "Encapsulation of Mg-Zr alloy in metakaolin-based geopolymer" Rooses A, Steins P, Dannoux-Papin A, Lambertin D, Poulesquen A and Frizon F, APPLIED CLAY SCIENCE., MAR, {2013}. Vol. {73}({SI}), pp. {86-92}. (2013). |
| Abstract: Investigations were carried out to propose a suitable material for the encapsulation of Mg-Zr alloy wastes issued from fuel cladding of the first generation nuclear reactors. Stability over time, good mechanical properties and low gas production are the main requirements that embedding matrices must comply with in order to be suitable for long run storage. One of the main issues encapsulating Mg-Zr alloy in mineral binder is the hydrogen production related to Mg-Zr alloys corrosion and water radiolysis process. In this context, metakaolin geopolymers offer an interesting outlook: corrosion densities of Mg-Zr alloys are significantly lower than in Portland cement. This work firstly presents the hydrogen production of Mg-Zr alloy embedded in geopolymers prepared from different the activation solution (NaOH or KOH). The effect of addition of fluorine on the magnesium corrosion in geopolymer has been investigated too. The results point out that sodium geopolymer is a suitable binder for Mg-Zr alloy encapsulation with respect to magnesium corrosion resistance. Furthermore the presence of fluorine reduces significantly the hydrogen release. Then, the impact of fluorine on the geopolymer network formation was studied by rheological, calorimetric and F-19 NMR measurements. No direct effect resulting from the addition of fluorine has been shown on the geopolymer binder. Secondly, the formulation of the encapsulation matrix has been adjusted to fulfil the expected physical and mechanical properties. Observations, dimensional evolutions and compressive strengths demonstrated that addition of sand to the geopolymer binder is efficient to meet the storage criteria. Consequently, a matrix formulation compatible with Mg-Zr alloy encapsulation has been proposed. Finally, irradiation tests have been carried out to assess the hydrogen radiolytic yield of the matrix under exposure to gamma radiation. (c) 2012 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000317798600013,
author = {Rooses, Adrien and Steins, Prune and Dannoux-Papin, Adeline and Lambertin, David and Poulesquen, Arnaud and Frizon, Fabien},
title = {Encapsulation of Mg-Zr alloy in metakaolin-based geopolymer},
journal = {APPLIED CLAY SCIENCE},
year = {2013},
volume = {73},
number = {SI},
pages = {86-92},
doi = {10.1016/j.clay.2012.09.023}
}
|
| "Light-induced tryptophan radical generation in a click modular assembly of a sensitiser-tryptophan residue" Sheth S, Baron A, Herrero C, Vauzeilles B, Aukauloo A and Leibl W, PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES. Vol. {12}({6}), pp. {1074-1078}. (2013). |
| Abstract: Click chemistry was used as an efficient method to covalently attach a chromophore to an amino acid. Such easily prepared model systems allow for time-resolved studies of one-electron oxidation reactions by the excitation of the chromophore by a laser flash. The model complex ruthenium-tryptophan (Ru-Trp) has been synthesised and studied for its photophysical and electrochemical properties. Despite a small driving force of less than 100 meV, excitation with a laser flash results in fast internal electron transfer leading to the formation of the protonated radical (Trp(center dot)H(+)). At neutral pH electron transfer is followed by deprotonation to form the neutral Trp(center dot) radical with the rate depending on the concentration of water acting as the proton acceptor. The formation of the tryptophan radical was confirmed by EPR. |
BibTeX:
@article{ISI:000319228600012,
author = {Sheth, Sujitraj and Baron, Aurelie and Herrero, Christian and Vauzeilles, Boris and Aukauloo, Ally and Leibl, Winfried},
title = {Light-induced tryptophan radical generation in a click modular assembly of a sensitiser-tryptophan residue},
journal = {PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES},
year = {2013},
volume = {12},
number = {6},
pages = {1074-1078},
doi = {10.1039/c3pp50021g}
}
|
| "Gamma radiation effect on gas production in anion exchange resins" Traboulsi A, Labed V, Dauvois V, Dupuy N and Rebufa C, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS., OCT 1, {2013}. Vol. {312}, pp. {7-14}. (2013). |
| Abstract: Radiation-induced decomposition of Amberlite IRA400 anion exchange resin in hydroxide form by gamma radiolysis has been studied at various doses in different atmospheres (anaerobic, anaerobic with liquid water, and aerobic). The effect of these parameters on the degradation of ion exchange resins is rarely investigated in the literature. We focused on the radiolysis gases produced by resin degradation. When the resin was irradiated under anaerobic conditions with liquid water, the liquid phase over the resin was also analyzed to identify any possible water-soluble products released by degradation of the resin. The main products released are trimethylamine (TMA), molecular hydrogen (H-2g) and carbon dioxide (CO2g). TMA and H-2g are produced in all the irradiation atmospheres. However, TMA was in gaseous form under anaerobic and aerobic conditions and in aqueous form in presence of liquid water. In the latter conditions, TMA(aq) was associated with aqueous dimethylamine (DMA(aq)), monomethylamine (MMA(aq)) and ammonia (NH4aq+). CO2g is formed in the presence of oxygen due to oxidation of organic compounds present in the system, in particular the degradation products such as TMA(g). (c) 2013 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000324657500002,
author = {Traboulsi, A. and Labed, V. and Dauvois, V. and Dupuy, N. and Rebufa, C.},
title = {Gamma radiation effect on gas production in anion exchange resins},
journal = {NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS},
year = {2013},
volume = {312},
pages = {7-14},
doi = {10.1016/j.nimb.2013.06.021}
}
|
| "Hydrogen bonding to the cysteine ligand of superoxide reductase: acid-base control of the reaction intermediates" Tremey E, Bonnot F, Moreau Y, Berthomieu C, Desbois A, Favaudon V, Blondin G, Houee-Levin C and Niviere V, JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY., OCT, {2013}. Vol. {18}({7}), pp. {815-830}. (2013). |
| Abstract: Superoxide reductase (SOR) is a non-heme iron metalloenzyme that detoxifies superoxide radical in microorganisms. Its active site consists of an unusual non-heme Fe2+ center in a [His(4)Cys(1)] square pyramidal pentacoordination, with the axial cysteine ligand proposed to be an essential feature in catalysis. Two NH peptide groups from isoleucine 118 and histidine 119 establish hydrogen bonds involving the sulfur ligand (Desulfoarculus baarsii SOR numbering). To investigate the catalytic role of these hydrogen bonds, the isoleucine 118 residue of the SOR from Desulfoarculus baarsii was mutated into alanine, aspartate, or serine residues. Resonance Raman spectroscopy showed that the mutations specifically induced an increase of the strength of the Fe3+-S(Cys) and S-C-beta(Cys) bonds as well as a change in conformation of the cysteinyl side chain, which was associated with the alteration of the NH hydrogen bonding involving the sulfur ligand. The effects of the isoleucine mutations on the reactivity of SOR with O-2 (aEuro cent a') were investigated by pulse radiolysis. These studies showed that the mutations induced a specific increase of the pK (a) of the first reaction intermediate, recently proposed to be an Fe2+-O-2 (aEuro cent a') species. These data were supported by density functional theory calculations conducted on three models of the Fe2+-O-2 (aEuro cent a') intermediate, with one, two, or no hydrogen bonds involving the sulfur ligand. Our results demonstrated that the hydrogen bonds between the NH (peptide) and the cysteine ligand tightly control the rate of protonation of the Fe2+-O-2 (aEuro cent a') reaction intermediate to form an Fe3+-OOH species. |
BibTeX:
@article{ISI:000324636200009,
author = {Tremey, Emilie and Bonnot, Florence and Moreau, Yohann and Berthomieu, Catherine and Desbois, Alain and Favaudon, Vincent and Blondin, Genevieve and Houee-Levin, Chantal and Niviere, Vincent},
title = {Hydrogen bonding to the cysteine ligand of superoxide reductase: acid-base control of the reaction intermediates},
journal = {JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY},
year = {2013},
volume = {18},
number = {7},
pages = {815-830},
doi = {10.1007/s00775-013-1025-1}
}
|
| 2012 |
| "Degradation of erioglaucine dye under gamma-irradiation" Azar F, Yang HB, Venault L and Faure S, In ATALANTE 2012 INTERNATIONAL CONFERENCE ON NUCLEAR CHEMISTRY FOR SUSTAINABLE FUEL CYCLES. Vol. {7}, pp. {647-653}. (2012). |
| Abstract: The kinetics and the mechanism degradation of erioglaucine dye in aqueous solution irradiated under gamma-rays from Co-60 are investigated. From the results of the absorption UV-Vis spectra of 0.7 mM erioglaucine solution as function of dose, the concentration of erioglaucine decreases exponentially with increasing the gamma-irradiation dose and the plot on a logarithmic scale against the dose shows a clear pseudo first order rate. The apparent pseudo-first order rate constant (k(app)=1.8x10(-3) min(-1)) was calculated. We also found the degradation mechanism as results of mass-spectrum analyses of the degradation products under the gamma-irradiated erioglaucine solution. The results show that the principal cleavage is the C-N bond. (C) 2012 Elsevier B.V...Selection and/or peer-review under responsibility of the Chairman of the ATALANTE 2012 Program Committee |
BibTeX:
@inproceedings{ISI:000312637500095,
author = {Azar, F. and Yang, H. -B. and Venault, L. and Faure, S.},
editor = {Poinssot, C},
title = {Degradation of erioglaucine dye under gamma-irradiation},
booktitle = {ATALANTE 2012 INTERNATIONAL CONFERENCE ON NUCLEAR CHEMISTRY FOR SUSTAINABLE FUEL CYCLES},
year = {2012},
volume = {7},
pages = {647-653},
note = {International Conference on Nuclear Chemistry for Sustainable Fuel Cycles (ATALANTE), Montpellier, FRANCE, SEP 03-07, 2012},
doi = {10.1016/j.proche.2012.10.098}
}
|
| "Radiolysis of astrophysical ices by heavy ion irradiation: Destruction cross section measurement" de Barros ALF, Boduch P, Domaracka A, Rothard H and da Silveira EF, LOW TEMPERATURE PHYSICS., AUG, {2012}. Vol. {38}({8}), pp. {759-765}. (2012). |
| Abstract: Many solar system objects, such as planets and their satellites, dust grains in rings, and comets, are known to either be made of ices or to have icy surfaces. These ices are exposed to ionizing radiation including keV, MeV and GeV ions from solar wind or cosmic rays. Moreover, icy dust grains are present in interstellar space and, in particular, in dense molecular clouds. Radiation effects include radiolysis (the destruction of molecules leading to formation of radicals), the formation of new molecules following radiolysis, the desorption or sputtering of atoms or molecules from the surface, compaction of porous ices, and phase changes. This review discusses the application of infrared spectroscopy FTIR to study the evolution of the chemical composition of ices containing the most abundant molecular species found in the solar system and interstellar medium, such as H2O, CO, CO2 and hydrocarbons. We focus on the evolution of chemical composition with ion fluence in order to deduce the corresponding destruction and formation cross sections. Although initial approach focused on product identification, it became increasingly necessary to work toward a comprehensive understanding of ice chemistry. The abundances of these molecules in different phases of ice mantles provide important clues to the chemical processes in dense interstellar clouds, and therefore it is of importance to accurately measure the quantities such as dissociation and formation cross sections of the infrared features of these molecules. We also are able to obtain the scaling of these cross sections with deposited energy. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4743476] |
BibTeX:
@article{ISI:000308384200015,
author = {de Barros, A. L. F. and Boduch, P. and Domaracka, A. and Rothard, H. and da Silveira, E. F.},
title = {Radiolysis of astrophysical ices by heavy ion irradiation: Destruction cross section measurement},
journal = {LOW TEMPERATURE PHYSICS},
year = {2012},
volume = {38},
number = {8},
pages = {759-765},
doi = {10.1063/1.4743476}
}
|
| "A Novel Cryo-Reduction Method to Investigate the Molecular Mechanism of Nitric Oxide Synthases" Bernad S, Brunel A, Dorlet P, Sicard-Roselli C and Santolini J, JOURNAL OF PHYSICAL CHEMISTRY B., MAY 17, {2012}. Vol. {116}({19}), pp. {5595-5603}. (2012). |
| Abstract: Nitric oxide synthases (NOSs) are hemoproteins responsible for the biosynthesis of NO in mammals. They catalyze two successive oxidation reactions. The mechanism of oxygen activation is based on the transfer of two electrons and two protons. Despite structural analogies with cytochromes P450, the molecular mechanism of NOS remains yet to be elucidated. Because of extremely high reaction rates, conventional kinetics methods failed to trap and characterize the major reaction intermediates. Cryo-reduction methods offer a possibility to circumvent this technological lock, by triggering oxygen activation at cryogenic temperatures by using water radiolysis. However, this method is not adapted to the NOS mechanism because of the high instability of the initial (FeO2)-O-II complex (extremely fast autoxidation and/or reaction with the cofactor H4B). This imposed a protocol with a stable (FeO2)-O-II complex (observed only for one NOS-like protein) and that excludes any redox role for H4B. A relevant approach to the NOS mechanism would use H4B to provide the (second) electron involved in oxygen activation; water radiolysis would thus provide the first electron (heme reduction). In this context, we report here an investigation of the first electron transfer by this alternative approach, i.e., the reduction of native NOS by water radiolysis. We combined EPR and resonance Raman spectroscopies to analyze NOS reduction for a combination of different substrates, cofactor, and oxygen concentrations, and for different NOS isoforms. Our results show that cryo-reduction of native NOS is achieved for all conditions that are relevant to the investigation of the NOS mechanism. |
BibTeX:
@article{ISI:000304073400003,
author = {Bernad, Sophie and Brunel, Albane and Dorlet, Pierre and Sicard-Roselli, Cecile and Santolini, Jerome},
title = {A Novel Cryo-Reduction Method to Investigate the Molecular Mechanism of Nitric Oxide Synthases},
journal = {JOURNAL OF PHYSICAL CHEMISTRY B},
year = {2012},
volume = {116},
number = {19},
pages = {5595-5603},
doi = {10.1021/jp300749b}
}
|
| "Control of the Evolution of Iron Peroxide Intermediate in Superoxide Reductase from Desulfoarculus baarsii. Involvement of Lysine 48 in Protonation" Bonnot F, Molle T, Menage S, Moreau Y, Duval S, Favaudon V, Houee-Levin C and Niviere V, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY., MAR 21, {2012}. Vol. {134}({11}), pp. {5120-5130}. (2012). |
| Abstract: Superoxide reductase is a nonheme iron metalloenzyme that detoxifies superoxide anion radicals O-2(center dot-) in some microorganisms. Its catalytic mechanism was previously proposed to involve a single ferric iron (hydro)peroxo intermediate, which is protonated to form the reaction product H2O2. Here, we show by pulse radiolysis that the mutation of the well-conserved lysine 48 into isoleucine in the SOR from Desulfoarculus baarsii dramatically affects its reaction with O-2(center dot-). Although the first reaction intermediate and its decay are not affected by the mutation, H2O2 is no longer the reaction product. In addition, in contrast to the wild-type SOR, the lysine mutant catalyzes a two-electron oxidation of an olefin into epoxide in the presence of H2O2, suggesting the formation of iron-oxo intermediate species in this mutant. In agreement with the recent X-ray structures of the peroxide intermediates trapped in a SOR crystal, these data support the involvement of lysine 48 in the specific protonation of the proximal oxygen of the peroxide intermediate to generate H2O2, thus avoiding formation of iron-oxo species, as is observed in cytochrome P450. In addition, we proposed that the first reaction intermediate observed by pulse radiolysis is a ferrous-iron superoxo species, in agreement with TD-DFT calculations of the absorption spectrum of this intermediate. A new reaction scheme for the catalytical mechanism of SOR with O-2(center dot-) is presented in which ferrous iron-superoxo and ferric hydroperoxide species are reaction intermediates, and the lysine 48 plays a key role in the control of the evolution of iron peroxide intermediate to form H2O2. |
BibTeX:
@article{ISI:000302191900025,
author = {Bonnot, Florence and Molle, Thibaut and Menage, Stephane and Moreau, Yohann and Duval, Simon and Favaudon, Vincent and Houee-Levin, Chantal and Niviere, Vincent},
title = {Control of the Evolution of Iron Peroxide Intermediate in Superoxide Reductase from Desulfoarculus baarsii. Involvement of Lysine 48 in Protonation},
journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY},
year = {2012},
volume = {134},
number = {11},
pages = {5120-5130},
doi = {10.1021/ja209297n}
}
|
| "The solubility constant of calcium peroxide octahydrate in relation to temperature; its influence on radiolysis in cement-based materials" Bouniol P and Lapuerta-Cochet S, JOURNAL OF NUCLEAR MATERIALS., JAN, {2012}. Vol. {420}({1-3}), pp. {16-22}. (2012). |
| Abstract: The solubility constant of calcium peroxide octahydrate (K-per) is determined in relation to temperature through an experimental method based on pH monitoring. The value of K-per = (CaOH+) (HO2-) (H2O)(7) is provided by the modified Arrhenius expression K-per = 7.329 x 10(-161) x T-58.929 X exp(5061.5/T). At 25 degrees C, K-per = (1.13 +/- 0.01) x 10(-7). That expression takes into account the kinetics of the homogeneous decomposition of hydrogen peroxide according to the H2O2 + HO2- -> H2O + OH- + O-2 mechanism. The variation of the rate constant with temperature is achieved by completing the data taken from the literature by observing the kinetics at 65 degrees C and is expressed as k = A x exp (-E-a/RT) where A = 600 M-1 s(-1) and E-a = 35 kJ/mol. At 25 degrees C, k = (4.5 +/- 0.1) x 10(-4) M-1 s(-1). In parallel, a new presentation of the available data on calcium equilibria in relation to temperature (complexation of Ca2+ and of CaOH+, solubility of portlandite) is used to support the simulations made on the overall system (calcium + peroxide). By integrating the new data, it is possible to forecast a specific behaviour of gamma radiolysis in a cement-based material as a function of the temperature. Below 25 degrees C, CaO2 center dot 8H(2)O precipitation acts in synergy with Allen's chain-reaction and leads rapidly to a stationary state with a small amount of H-2. At 25 degrees C and above, precipitation stops, the stationary state is more difficult to achieve and the production of both H-2 and O-2 is significantly higher. (C) 2011 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000300462300003,
author = {Bouniol, P. and Lapuerta-Cochet, S.},
title = {The solubility constant of calcium peroxide octahydrate in relation to temperature; its influence on radiolysis in cement-based materials},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2012},
volume = {420},
number = {1-3},
pages = {16-22},
doi = {10.1016/j.jnucmat.2011.09.009}
}
|
| "In situ Raman monitoring of materials under irradiation: study of uranium dioxide alteration by water radiolysis" Canizares A, Guimbretiere G, Tobon YA, Raimboux N, Omnee R, Perdicakis M, Muzeau B, Leoni E, Alam MS, Mendes E, Simon D, Matzen G, Corbel C, Barthe MF and Simon P, JOURNAL OF RAMAN SPECTROSCOPY., OCT, {2012}. Vol. {43}({10}), pp. {1492-1497}. (2012). |
| Abstract: In situ Raman scattering studies allow following real-time evolutions of volume or surface structures under extreme conditions. In nuclear materials sciences, ion irradiation-induced atomic organization modification and water radiolysis are of a major interest. In order to better understand these phenomena, we have developed an in situ versatile portable Raman spectroscopy system coupled with a cyclotron accelerator, allowing monitoring of a solid/liquid interface under irradiation and thus giving access to effects of radiolysis. The different parts of the system and their improvements are described in details. The system efficiency is highlighted by a comparative study of the time dependence of UO2 surface modification induced, on one hand by contact with water under irradiation by 5?MeV He2+ particles, and on the other hand by pure chemical alteration, through contact with a hydrogen peroxide solution. Copyright (c) 2012 John Wiley & Sons, Ltd. |
BibTeX:
@article{ISI:000310248400022,
author = {Canizares, A. and Guimbretiere, G. and Tobon, Y. A. and Raimboux, N. and Omnee, R. and Perdicakis, M. and Muzeau, B. and Leoni, E. and Alam, M. S. and Mendes, E. and Simon, D. and Matzen, G. and Corbel, C. and Barthe, M. F. and Simon, P.},
title = {In situ Raman monitoring of materials under irradiation: study of uranium dioxide alteration by water radiolysis},
journal = {JOURNAL OF RAMAN SPECTROSCOPY},
year = {2012},
volume = {43},
number = {10},
pages = {1492-1497},
doi = {10.1002/jrs.4088}
}
|
| "Topological analysis of the structure of self-irradiated sodium borosilicate glass" Dewan L, Hobbs LW and Delaye J-M, JOURNAL OF NON-CRYSTALLINE SOLIDS., DEC 15, {2012}. Vol. {358}({24, SI}), pp. {3427-3432}. (2012). |
| Abstract: High-level nuclear waste glasses must maintain their mechanical and chemical stability over very long time scales. Self-irradiation damage in these glasses induces bond-breakage and atomic displacements by two distinct mechanisms: radiolysis (principally from energetic beta-decay electrons) and ballistic mechanisms involving collision cascades initiated by energetic fission nuclei and recoil of alpha-emitting actinide nuclei. This study investigates collision-cascade-induced alteration of the glass network in a simplified sodium borosilicate model nuclear waste glass, using molecular dynamics (MD) simulation and efficient topological assessment algorithms. Network topologies of the initial and resulting altered glass structures were determined by enumerating the primitive-ring-based local cluster atom complements at each atom site. The topological description is seen to provide a revealing assessment of network structural changes in the simulated radiation environment. (c) 2012 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000312479500004,
author = {Dewan, Leslie and Hobbs, Linn W. and Delaye, Jean-Marc},
title = {Topological analysis of the structure of self-irradiated sodium borosilicate glass},
journal = {JOURNAL OF NON-CRYSTALLINE SOLIDS},
year = {2012},
volume = {358},
number = {24, SI},
pages = {3427-3432},
note = {19th University Conference on Glass Science, Rensselaer Polytechn Inst, Troy, NY, AUG 03-05, 2011},
doi = {10.1016/j.jnoncrysol.2012.04.033}
}
|
| "Radiation-induced nitration of organic compounds in aqueous solutions" Ershov BG, Gordeev AV, Bykov GL and Moisy P, RADIOCHIMICA ACTA. Vol. {100}({12}), pp. {919-923}. (2012). |
| Abstract: Radiolysis in aqueous nitrate and acetic acid solutions and nitrate/nitric acid and phenol was studied. The radiolysis of these solutes occurs with (NO2)-N-center dot radical, which is the active nitrating agent. Accumulation of nitromethane and nitrite was determined during gamma-irradiation of aqueous solutions containing acetic and nitrate solutions. Irradiation of aqueous phenol-nitrate/nitric acid solutions results in the formation of 2- and 4-nitrophenols. |
BibTeX:
@article{ISI:000313372800008,
author = {Ershov, B. G. and Gordeev, A. V. and Bykov, G. L. and Moisy, Ph.},
title = {Radiation-induced nitration of organic compounds in aqueous solutions},
journal = {RADIOCHIMICA ACTA},
year = {2012},
volume = {100},
number = {12},
pages = {919-923},
doi = {10.1524/ract.2012.1977}
}
|
| "Irradiation of Ethylene/Styrene Copolymers: Evidence of Sensitization of the Aromatic Moiety As Counterpart of the Radiation Protection Effect" Ferry M, Bessy E, Harris H, Lutz PJ, Ramillon JM, Ngono-Ravache Y and Balanzat E, JOURNAL OF PHYSICAL CHEMISTRY B., FEB 16, {2012}. Vol. {116}({6}), pp. {1772-1776}. (2012). |
| Abstract: Molecules containing aromatics systems are more stable in the presence of ionizing radiations than alkanes. In the same way, introducing aromatic rings into aliphatic compounds increases their stability. The protective effect is nonlocal and likely results from the transfer of energy and species from the aliphatic moiety to the aromatic one. For years, it was commonly assumed that the aromatic moiety, which is very radiation resistant, accommodates the extra energy remaining unaffected. The use of Fourier transform infrared spectroscopy, online with high energy ion beam irradiation of ethylene/styrene random copolymers, allows us to bring experimental evidence that the benzene rings are sensitized by transfer reactions and consequently that this effect is more important in polymers with low benzene ring molar content. |
BibTeX:
@article{ISI:000300274900004,
author = {Ferry, M. and Bessy, E. and Harris, H. and Lutz, P. J. and Ramillon, J. -M. and Ngono-Ravache, Y. and Balanzat, E.},
title = {Irradiation of Ethylene/Styrene Copolymers: Evidence of Sensitization of the Aromatic Moiety As Counterpart of the Radiation Protection Effect},
journal = {JOURNAL OF PHYSICAL CHEMISTRY B},
year = {2012},
volume = {116},
number = {6},
pages = {1772-1776},
doi = {10.1021/jp209535p}
}
|
| "Study of long term behavior of intermediate level long lived waste packages: an overview of the R&D approach and results" Lamouroux C and Cochin F , In ATALANTE 2012 INTERNATIONAL CONFERENCE ON NUCLEAR CHEMISTRY FOR SUSTAINABLE FUEL CYCLES. Vol. {7}, pp. {559-566}.(2012). |
| Abstract: This paper addresses the radiolysis phenomenon on organic compounds leading to the formation of new molecular species such as gases and small soluble molecules. A large number of industrial and pure polymers were irradiated either with gamma radiation or swift heavy ions. Radiolytic yields were determined and the effects of the dose and the oxidation of materials were studied. A specific tool dedicated to the determination of the energy released through organic materials by alpha particles was developed. The release of chemical species such as carboxylic acids from more than twenty polymers under gamma and simulated alpha radiolysis at different cumulated dose was also described. (C) 2012 Elsevier B.V...Selection and/or peer-review under responsibility of the Chairman of the ATALANTE 2012 Program Committee |
BibTeX:
@inproceedings{ISI:000312637500082,
author = {Lamouroux, C. and Cochin, F.},
editor = {Poinssot, C},
title = {Study of long term behavior of intermediate level long lived waste packages: an overview of the R&D approach and results},
booktitle = {ATALANTE 2012 INTERNATIONAL CONFERENCE ON NUCLEAR CHEMISTRY FOR SUSTAINABLE FUEL CYCLES},
year = {2012},
volume = {7},
pages = {559-566},
note = {International Conference on Nuclear Chemistry for Sustainable Fuel Cycles (ATALANTE), Montpellier, FRANCE, SEP 03-07, 2012},
doi = {10.1016/j.proche.2012.10.085}
}
|
| "Modifications under Irradiation of a Self-Assembled Monolayer Grafted on a Nanoporous Silica Glass: A Solid-State NMR Characterization" Le Caer S, Brunet F, Chatelain C, Durand D, Dauvois V, Charpentier T and Renault JP, JOURNAL OF PHYSICAL CHEMISTRY C., FEB 23, {2012}. Vol. {116}({7}), pp. {4748-4759}. (2012). |
| Abstract: Controlled pore glasses with a pore size of 8 nm are grafted with chlorodimethylsilane (ClSi(CH3)(2)H). The surface of the glass is carefully characterized before and after irradiation with 10 MeV electrons by solid-state NMR measurements. H-1 MAS NMR experiments in one and two dimensions (2D double quantum and 2D exchange) have been used to reveal the grafting of the chlorodimethylsilane at the silica surface and evidence the formation of a homogeneous layer on the surface. Irradiation leads to a high H-2 yield (3.3 x 10(-7) mol/J) due to the efficient cleavage of the Si H bond. Methane is detected in smaller quantities (5.5 X 10(-8) mol/J), indicating that the Si H bond is preferentially cleaved over the Si C bond. The H2 production arising from OH groups on the surface is very minor in comparison to the Si H and Si C radiolysis. |
BibTeX:
@article{ISI:000301156500049,
author = {Le Caer, S. and Brunet, F. and Chatelain, C. and Durand, D. and Dauvois, V. and Charpentier, T. and Renault, J. Ph.},
title = {Modifications under Irradiation of a Self-Assembled Monolayer Grafted on a Nanoporous Silica Glass: A Solid-State NMR Characterization},
journal = {JOURNAL OF PHYSICAL CHEMISTRY C},
year = {2012},
volume = {116},
number = {7},
pages = {4748-4759},
doi = {10.1021/jp211639u}
}
|
| "Experimental and theoretical study of the degradation of malonamide extractant molecules under ionizing radiation" Le Caer S, Vigneron G, Guillaumont D, Berthon L, Zorz N and Moisy P, RSC ADVANCES. Vol. {2}({9}), pp. {3954-3967}. (2012). |
| Abstract: The behavior of three malonamides diluted in octane and submitted to ionizing radiation has been studied by means of in situ infrared spectroscopy, electrospray ionization mass spectrometry and quantum chemistry calculations. The major channel at low dose for a malonamide with ethyl groups on the nitrogen atoms and no substituent on the central carbon atom arises from the addition of an octyl group from the solvent. Adding alkyl chains on the nitrogen atoms and/or an alkyl chain on the central carbon atom weakens the central C-C bond which is then preferentially cleaved upon irradiation. The other bond cleavages (both C-N and C-H cleavages) are then detected when increasing the dose. |
BibTeX:
@article{ISI:000302810800061,
author = {Le Caer, S. and Vigneron, G. and Guillaumont, D. and Berthon, L. and Zorz, N. and Moisy, P.},
title = {Experimental and theoretical study of the degradation of malonamide extractant molecules under ionizing radiation},
journal = {RSC ADVANCES},
year = {2012},
volume = {2},
number = {9},
pages = {3954-3967},
doi = {10.1039/c2ra01201d}
}
|
| "Nanosecond Pulse Radiolysis of Nanoconfined Water" Musat RM, Cook AR, Renault J-P and Crowell RA, JOURNAL OF PHYSICAL CHEMISTRY C., JUN 21, {2012}. Vol. {116}({24}), pp. {13104-13110}. (2012). |
| Abstract: The radiation chemistry of water in 1 and 57 nm pore diameter controlled pore glass is studied using nanosecond pulse radiolysis and compared to that of the bulk. The absorption spectrum of the solvated electron shows little dependence on the pore size suggesting that they solvate within the pore. It is shown that the reaction rate of the solvated electron increases dramatically with decreasing pore size, going from 6.8 X 10(6) s(-1) in the bulk to 34.7 X 10(6) s(-1) in a 1 nm pore. The initial yield (at 20 ns) shows an increase of 2.03 +/- 0.01 in a 1 nm pore relative to the bulk. Formation of the solvated electron most likely occurs by an energy transfer process that occurs at the interface followed by diffusion into the pore. |
BibTeX:
@article{ISI:000305444300014,
author = {Musat, Raluca M. and Cook, Andrew R. and Renault, Jean-Philippe and Crowell, Robert A.},
title = {Nanosecond Pulse Radiolysis of Nanoconfined Water},
journal = {JOURNAL OF PHYSICAL CHEMISTRY C},
year = {2012},
volume = {116},
number = {24},
pages = {13104-13110},
doi = {10.1021/jp301000c}
}
|
| "Effect of groundwater on the dissolution rate of the simulated nuclear waste glass SON68 under gamma irradiation" Rolland S, Tribet M, Broudic V, Jollivet P, Jegou C and Toulhoat P, In ATALANTE 2012 INTERNATIONAL CONFERENCE ON NUCLEAR CHEMISTRY FOR SUSTAINABLE FUEL CYCLES. Vol. {7}, pp. {587-592}. (2012). |
| Abstract: The leaching behaviour of the inactive reference of the R7T7 glass is investigated here in a synthetic clayey groundwater solution, focusing on the effect of gamma irradiation on this residual alteration rate, under static conditions, at 90 degrees C. Results don't underline any significant effect of gamma irradiation on the residual alteration rate up to 5kGy/h, compared to experiments performed out of irradiation in groundwater or in pure water. Moreover, the evolution of boron releases in groundwater versus time is similar whatever the dose rate. These observations are consistent with SEM characterizations. (C) 2012 Elsevier B.V...Selection and/or peer-review under responsibility of the Chairman of the ATALANTE 2012 Program Committee |
BibTeX:
@inproceedings{ISI:000312637500086,
author = {Rolland, S. and Tribet, M. and Broudic, V. and Jollivet, P. and Jegou, C. and Toulhoat, P.},
editor = {Poinssot, C},
title = {Effect of groundwater on the dissolution rate of the simulated nuclear waste glass SON68 under gamma irradiation},
booktitle = {ATALANTE 2012 INTERNATIONAL CONFERENCE ON NUCLEAR CHEMISTRY FOR SUSTAINABLE FUEL CYCLES},
year = {2012},
volume = {7},
pages = {587-592},
note = {International Conference on Nuclear Chemistry for Sustainable Fuel Cycles (ATALANTE), Montpellier, FRANCE, SEP 03-07, 2012},
doi = {10.1016/j.proche.2012.10.089}
}
|
| "Investigation of gamma radiation effect on the anion exchange resin Amberlite IRA-400 in hydroxide form by Fourier transformed infrared and C-13 nuclear magnetic resonance spectroscopies" Traboulsi A, Dupuy N, Rebufa C, Sergent M and Labed V, ANALYTICA CHIMICA ACTA., MAR 2, {2012}. Vol. {717}, pp. {110-121}.(2012). |
| Abstract: Radiation-induced decomposition of the anion exchange resin Amberlite IRA-400 in hydroxide form by gamma radiolysis has been studied under different irradiation doses and irradiation atmospheres. In this work, we focused on the degradation of the solid part of the resin by Fourier transformed infrared (FTIR) and C-13 nuclear magnetic resonance (NMR) spectroscopies associated with chemometric treatments. FTIR and C-13 NMR techniques showed that only-CH2N+(CH3)(3) groups were detached from the resin whereas the polystyrene divinylbenzene backbone remains intact. The quaternary ammonium groups were replaced by amine or carbonyl groups according to the irradiation atmosphere (with or without water or oxygen). Principal components analysis (PCA) was used to classify the degraded resins according to their irradiation conditions by separating the effect of the dose or the environment. The PCA loadings have shown spectral regions which discriminate the irradiated resins whereas SIMPLe-to-use Interactive Self-modeling Mixture Analysis (SIMPLISMA) allows to identify families of component characterizing the chemical structure of resins and estimate their relative contributions according to the irradiation atmospheres. (C) 2011 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000301566200013,
author = {Traboulsi, A. and Dupuy, N. and Rebufa, C. and Sergent, M. and Labed, V.},
title = {Investigation of gamma radiation effect on the anion exchange resin Amberlite IRA-400 in hydroxide form by Fourier transformed infrared and C-13 nuclear magnetic resonance spectroscopies},
journal = {ANALYTICA CHIMICA ACTA},
year = {2012},
volume = {717},
pages = {110-121},
doi = {10.1016/j.aca.2011.12.046}
}
|
| "Mechanism of radiation-induced reactions in aqueous solution of coumarin-3-carboxylic acid: Effects of concentration, gas and additive on fluorescent product yield" Yamashita S, Baldacchino G, Maeyama T, Taguchi M, Muroya Y, Lin M, Kimura A, Murakami T and Katsumura Y, FREE RADICAL RESEARCH., JUL, {2012}. Vol. {46}({7}), pp. {861-871}. (2012). |
| Abstract: The radiation-induced reactions of a water-soluble coumarin derivative, coumarin-3-carboxyl acid (C3CA), have been investigated in aqueous solutions by pulse radiolysis with a 35 MeV electron beam, final product analysis following Co-60 gamma-irradiations and deterministic model simulations. Pulse radiolysis revealed that C3CA reacted with both hydroxyl radicals ((OH)-O-center dot) and hydrated electrons (e(aq)(-)) with near diffusion-controlled rate constants of 6.8 x 10(9) and 2.1 x 10(10) M-1 s(-1), respectively. The reactivity of C3CA towards O-2(center dot-) was not confirmed by pulse radiolysis. Production of the fluorescent molecule, 7-hydroxy-coumarin-3-carboxylic acid (7OH-C3CA), was confirmed by final product analysis with a fluorescence spectrometer coupled to a high performance liquid chromatography (HPLC) system. Production yields of 7OH-C3CA following Co-60.-irradiations depended on the irradiation conditions and ranged from 0.025 to 0.18 (100 eV)(-1). Yield varied with saturating gas, additive and C3CA concentration, implying the presence of at least two pathways capable of providing 7OH-C3CA as a stable product following the scavenging reaction of C3CA with (OH)-O-center dot, including a peroxidation/elimination sequence and a disproportionation pathway. A reaction mechanism for the two pathways was proposed and incorporated into a deterministic simulation, showing that the mechanism can explain experimentally measured 7OH-C3CA yields with a constant conversion factor of 4.7% from (OH)-O-center dot scavenging to 7OH-C3CA production, unless t-BuOH was added. |
BibTeX:
@article{ISI:000305246200005,
author = {Yamashita, Shinichi and Baldacchino, Gerard and Maeyama, Takuya and Taguchi, Mitsumasa and Muroya, Yusa and Lin, Mingzhang and Kimura, Atsushi and Murakami, Takeshi and Katsumura, Yosuke},
title = {Mechanism of radiation-induced reactions in aqueous solution of coumarin-3-carboxylic acid: Effects of concentration, gas and additive on fluorescent product yield},
journal = {FREE RADICAL RESEARCH},
year = {2012},
volume = {46},
number = {7},
pages = {861-871},
doi = {10.3109/10715762.2012.684879}
}
|
| 2011 |
| "Radiation effects on a linear model compound for polyethers" Aymes-Chodur C, Dannoux A, Dauvois V and Esnouf S, POLYMER DEGRADATION AND STABILITY., JUL, {2011}. Vol. {96}({7}), pp. {1225-1235}. (2011). |
| Abstract: Radiation effects on a model polyether - poly(tetramethylene) glycol (PTMG) induced by high energy radiation were investigated. To understand the degradation mechanism, electron paramagnetic resonance (EPR), Fourier transform infra-red spectroscopy (FTIR), electrospray and gas mass spectrometry (ESI-MS and gas-MS), were carried out to identify radicals and chemical modifications. Size exclusion chromatography (SEC) was used to follow the evolution of the distribution of molecular weight. On the basis of the results, a mechanism of degradation for PTMG is proposed. (C) 2011 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000292410800008,
author = {Aymes-Chodur, C. and Dannoux, A. and Dauvois, V. and Esnouf, S.},
title = {Radiation effects on a linear model compound for polyethers},
journal = {POLYMER DEGRADATION AND STABILITY},
year = {2011},
volume = {96},
number = {7},
pages = {1225-1235},
doi = {10.1016/j.polymdegradstab.2011.04.015}
}
|
| d "Cosmic ray impact on astrophysical ices: laboratory studies on heavy ion irradiation of methane" e Barros ALF, Bordalo V, Seperuelo Duarte E, da Silveira EF, Domaracka A, Rothard H and Boduch P, ASTRONOMY & ASTROPHYSICS., JUL, {2011}. Vol. {531}, (2011). |
| Abstract: Laboratory data of CH4 ice radiolysis promoted by fast heavy ions are obtained by infrared spectroscopy (FTIR). CH4 molecules are condensed on a CsI substrate at 15 K, and the ice layer is bombarded by 220 MeV O-16(7+) ion beam. The ice thickness is thin enough to be traversed by projectiles at constant velocity close to the equilibrium charge state. The induced CH4 dissociation gives rise to the formation of molecular species CH3, C2H2, C2H4, C2H6, and C3H8. Their formation and dissociation cross sections are determined. C2H6 represent the most abundant daughter molecules. The carbon budget analysis of CH4 and its radiolysis products shows that the column density of carbon atoms contained in the methane destroyed during ion irradiation is 30-50% greater than the sum for the column densities of the newly formed species. As an astrophysical implication, the current results allow estimation of chemical reaction rates in ices covering interstellar grains. |
BibTeX:
@article{ISI:000293017700038,
author = {de Barros, A. L. F. and Bordalo, V. and Seperuelo Duarte, E. and da Silveira, E. F. and Domaracka, A. and Rothard, H. and Boduch, P.},
title = {Cosmic ray impact on astrophysical ices: laboratory studies on heavy ion irradiation of methane},
journal = {ASTRONOMY & ASTROPHYSICS},
year = {2011},
volume = {531},
doi = {10.1051/0004-6361/201016021}
}
|
| "Radiolysis of frozen methanol by heavy cosmic ray and energetic solar particle analogues" de Barros ALF, Domaracka A, Andrade DPP, Boduch P, Rothard H and da Silveira EF, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY., DEC, {2011}. Vol. {418}({2}), pp. {1363-1374}. (2011). |
| Abstract: The chemical and physical effects induced by fast heavy ion irradiation on frozen pure methanol (CH3OH) at 15 K were studied. These energetic ions can simulate the energy transfer processes that occur by cosmic ray irradiation of interstellar ices, comets and icy Solar system bodies. The analysis was made by infrared spectroscopy (Fourier transform infrared) before and after irradiation, with 16-MeV 16O5+, 220-MeV 16O7+, 606-MeV 65Zn20+ and 774-MeV 86Kr31+ ion beams. Integrated values of the absorbance of the main methanol bands were determined. The induced CH3OH dissociation gives rise to the formation of molecular species, particularly H2CO, CH2OH, CH4, CO, CO2, HCO and HCOOCH3. Their formation and dissociation cross-sections were determined. H2CO and CH4 molecules are in general the most abundant new products of the four beams analysed. Except for the HCO and CH2OH species, cross-sections increased with the electronic stopping power, roughly as sigma similar to S3/2e. The G values for CH3OH destruction by fast heavy ion irradiation with Zn and Kr beams were found to be considerably larger than those for oxygen, helium or hydrogen. As an astrophysical implication, the S3/2e power law should be very helpful for predicting the CH3OH formation and dissociation cross-sections for other ion beam projectiles and energies. As astrophysical point of view, the analysis of the predictions reveals the unexpected importance of iron and some other heavy ion constituents of cosmic rays in astrochemistry. |
BibTeX:
@article{ISI:000297987400054,
author = {de Barros, A. L. F. and Domaracka, A. and Andrade, D. P. P. and Boduch, P. and Rothard, H. and da Silveira, E. F.},
title = {Radiolysis of frozen methanol by heavy cosmic ray and energetic solar particle analogues},
journal = {MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
year = {2011},
volume = {418},
number = {2},
pages = {1363-1374},
doi = {10.1111/j.1365-2966.2011.19587.x}
}
|
| "Water Radiolysis: Influence of Oxide Surfaces on H-2 Production under Ionizing Radiation" Le Caer S, WATER., MAR, {2011}. Vol. {3}({1}), pp. {235-253}. (2011). |
| Abstract: The radiolysis of water due to ionizing radiation results in the production of electrons, H-center dot atoms, (OH)-O-center dot radicals, H3O+ ions and molecules (dihydrogen H-2 and hydrogen peroxide H2O2). A brief history of the development of the understanding of water radiolysis is presented, with a focus on the H-2 production. This H-2 production is strongly modified at oxide surfaces. Different parameters accounting for this behavior are presented. |
BibTeX:
@article{ISI:000312254300013,
author = {Le Caer, Sophie},
title = {Water Radiolysis: Influence of Oxide Surfaces on H-2 Production under Ionizing Radiation},
journal = {WATER},
year = {2011},
volume = {3},
number = {1},
pages = {235-253},
doi = {10.3390/w3010235}
}
|
| "Production of a fluorescence probe in ion-beam radiolysis of aqueous coumarin-3-carboxylic acid solution-1: Beam quality and concentration dependences" Maeyama T, Yamashita S, Baldacchino G, Taguchi M, Kimura A, Murakami T and Katsumura Y, RADIATION PHYSICS AND CHEMISTRY., APR, {2011}. Vol. {80}({4}), pp. {535-539}. (2011). |
| Abstract: Aqueous coumarin-3-carboxylic acid (3-CCA) solutions were irradiated with seven different ion beams covering LET range from 0.5 to above 2000 eV/nm. G-values of 70H-CCA, one of hydroxylated products in radiolysis of the solutions, have been determined by fluorescence-HPLC technique in 3-CCA concentration range from 0.1 to 26 mM. The formation yield of 70H-CCA increased with increase in concentration of 3-CCA while it decreased with increase in LET value of ion beam. Compared with our previous reports on G((center dot)OH) at a scavenging capacity of 10(7) s(-1) with absorption spectroscopy, it was found that G(7OH-CCA) is about (4.7 +/- 0.6)% of G((center dot)OH), which is consistent for all of the ion beams used in the present study. However, 7OH-CCA yields in high 3-CCA concentration region, especially by using extremely high LET ions, were much higher than expected values based on the above conversion factor and G(OH) value predicted in theoretical work. (C) 2010 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000287624600002,
author = {Maeyama, Takuya and Yamashita, Shinichi and Baldacchino, Gerard and Taguchi, Mitsumasa and Kimura, Atsushi and Murakami, Takeshi and Katsumura, Yosuke},
title = {Production of a fluorescence probe in ion-beam radiolysis of aqueous coumarin-3-carboxylic acid solution-1: Beam quality and concentration dependences},
journal = {RADIATION PHYSICS AND CHEMISTRY},
year = {2011},
volume = {80},
number = {4},
pages = {535-539},
doi = {10.1016/j.radphyschem.2010.11.013}
}
|
| "Production of a fluorescence probe in ion-beam radiolysis of aqueous coumarin-3-carboxylic acid solution-2: Effects of nuclear fragmentation and its simulation with PHITS" Maeyama T, Yamashita S, Taguchi M, Baldacchino G, Sihver L, Murakami T and Katsumura Y, RADIATION PHYSICS AND CHEMISTRY., DEC, {2011}. Vol. {80}({12}), pp. {1352-1357}. (2011). |
| Abstract: The G(OH) values in aqueous coumarin-3-carboxylic-acid (3-CCA) solutions irradiated with (12)C(6+) beams having the energies of 135, 290 and 400 MeV/u were measured by a fluorescent method around the Bragg peak, with 0.6 mm intervals, and quartz cells of 1 cm optical lengths, at the Heavy Ion Medical Accelerator in Chiba, National Institute of Radiological Sciences (NIRS). For each ion, the G(OH) has been calculated as a function of dose average LET and position. The calculated results have been compared to measurements, and the results, reproducibility and reliability of the calculations are discussed in the paper. (C) 2011 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000295665100010,
author = {Maeyama, Takuya and Yamashita, Shinichi and Taguchi, Mitsumasa and Baldacchino, Gerard and Sihver, Lembit and Murakami, Takeshi and Katsumura, Yosuke},
title = {Production of a fluorescence probe in ion-beam radiolysis of aqueous coumarin-3-carboxylic acid solution-2: Effects of nuclear fragmentation and its simulation with PHITS},
journal = {RADIATION PHYSICS AND CHEMISTRY},
year = {2011},
volume = {80},
number = {12},
pages = {1352-1357},
doi = {10.1016/j.radphyschem.2011.07.004}
}
|
| "Effect of gamma irradiation on nuclear bituminized waste products (BWP): X-ray microtomography and rheological characterization" Mouazen M, Poulesquen A, Bart F and Vergnes B, JOURNAL OF NUCLEAR MATERIALS., DEC, {2011}. Vol. {419}({1-3}), pp. {24-31}. (2011). |
| Abstract: In the last 50 years bitumen has been widely used in France as a matrix for embedding low- and intermediate-level radioactive waste. This organic matrix is subjected to alpha, beta and gamma radiation generating radiolysis gases, which consist mainly of hydrogen but also some carbon oxide and lighter hydrocarbons. The gases form bubbles whose growth entails swelling of the bitumen if the radiolytic process of gas generation is more important than the removal process. To assess the influence of gamma radiation on the swelling and rheological behavior of the bitumen matrix, external gamma irradiation experiments were performed on pure bitumen (PB) and on a model synthesized bituminized waste product (BWP: 60 wt% bitumen + 40 wt% salts). Greater swelling was observed for the BWP samples than for PB. X-ray microtomography shows that the hydrogen bubbles are more numerous in the case of BWP, indicating that the salts may be considered as preferential nucleation sites. Moreover, the rheological characterization of the samples shows that the Newtonian viscosity is higher for the BWP model sample, and that the irradiation enhances this phenomenon. In the case of accelerated irradiation (dose rate exceeding the actual dose rate), swelling increases with the irradiation dose since the gas production rate is higher than the removal process until a plateau is reached at approximately 4-5 MGy, indicating an equilibrium between gas production and release. Finally, the impact of the dose rate on the number, size and shape of bubbles and on macroscopic swelling is discussed on the basis of X-ray microtomography results. (C) 2011 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000298936600004,
author = {Mouazen, M. and Poulesquen, A. and Bart, F. and Vergnes, B.},
title = {Effect of gamma irradiation on nuclear bituminized waste products (BWP): X-ray microtomography and rheological characterization},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2011},
volume = {419},
number = {1-3},
pages = {24-31},
doi = {10.1016/j.jnucmat.2011.07.025}
}
|
| "Electrochemical behaviour of stainless steel in PWR primary coolant conditions: Effects of radiolysis" Muzeau B, Perrin S, Corbel C, Simon D and Feron D, JOURNAL OF NUCLEAR MATERIALS., DEC, {2011}. Vol. {419}({1-3}), pp. {241-247}. (2011). |
| Abstract: Few data are available in the literature on the role of the water radiolysis on the corrosion of stainless steel core components in PWR operating conditions (300 degrees C, 155 bar). The present approach uses a high energy proton beam to control the production of radiolytic species at the interface between a stainless steel sample and water in a high temperature and high pressure (HP-HT) electrochemical cell working in the range 25 degrees C/1 bar-300 degrees C/90 bar. The cell is designed to record the free corrosion potential of the AISI 316L/water interface mounted in line with a cyclotron delivering the proton beam. The evolution of the potential is compared before, during and after the proton irradiation. The first results are obtained with an aqueous solution containing boron, lithium and dissolved hydrogen, as in PWR primary coolant circuit. The stainless steel/water interfaces are irradiated between 25 degrees C and 300 degrees C with protons emerging at 22 MeV at the interface. The flux is varied by five orders of magnitude, from 6.6 x 10(11) to 6.6 x 10(15) H(+) m(-2) s(-1). The evolution of the free corrosion potential is highly dependent on the temperature and/or pressure. For a given temperature and pressure, it evolves with the flux and the ageing of the AISI 316L/water interfaces. An important role of the temperature of irradiation on the electrochemical response was observed. These results give a better understanding of the role of radiolysis on stainless steel corrosion in high temperature conditions. (C) 2011 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000298936600030,
author = {Muzeau, Benoist and Perrin, Stephane and Corbel, Catherine and Simon, Dominique and Feron, Damien},
title = {Electrochemical behaviour of stainless steel in PWR primary coolant conditions: Effects of radiolysis},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2011},
volume = {419},
number = {1-3},
pages = {241-247},
doi = {10.1016/j.jnucmat.2011.08.051}
}
|
| "Development of normal phase-high performance liquid chromatography-atmospherical pressure chemical ionization-mass spectrometry method for the study of 6,6 `-bis-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-benzo [1,2,4]-triazin-3-yl)-[2,2 `]-bipyridine hydrolytic degradation" Nicolas G, Jankowski CK, Lucas-Lamouroux C and Bresson C, JOURNAL OF CHROMATOGRAPHY A., SEP 16, {2011}. Vol. {1218}({37}), pp. {6369-6378}. (2011). |
| Abstract: In the field of nuclear waste management, the 6,6'-bis-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydrobenzo[1,2,4]-triazin-3 -yl)-[2,2 `]-bipyridine (CyMe(4)BTBP) is a polycyclic N-based molecule eligible to remove actinides from spent nuclear fuel by liquid-liquid extraction processes. In such processes, the organic phase containing the extracting molecules will undergo hydrolysis and radiolysis, involving degradation products. The purpose of this work was to develop a normal phase chromatography (NP-HPLC) coupled to atmospherical pressure chemical ionisation-mass spectrometry (APCI-MS) method to separate and identify degradation products of CyMe(4)BTBP dissolved in octanol, submitted to HNO(3) hydrolysis. 1 mol L(-1) HNO(3) hydrolysis conditions were used regarding the selective actinides extraction (SANEX) process, while 3 mol L(-1) HNO(3) conditions were applied for the group actinide extraction (GANEX) process. The first step consisted in optimizing the chromatographic separation conditions using a diode array detection (DAD). Retention behavior of a non hydrolyzed mixture of N,N'-dimethyl-N,N'-dioctyl-hexyloxyethyl-malonamide (DMDOHEMA), a malonamide used in the SANEX process to increase the kinetic of extraction, and CyMe(4)BTBP were investigated on diol-, cyano-, and amino-bonded stationary phases using different mobile phase compositions. These latter were hexane with different polar modifiers, i.e. dioxane, isopropanol, ethanol and methylene chloride/methanol. The different retention processes in NP-HPLC were highlighted when using various stationary and mobile phases. The second step was the setting-up of the NP-HPLC-APCI-MS coupling and the use of the low-energy collision dissociation tandem mass spectrometry (CID-MS/MS) of the precursor protonated molecules that allowed the separation and the characterization of the main hydrolytic CyMe(4)BTBP degradation product under a 3 mol L(-1) HNO(3) concentration. Investigation of the CID-MS/MS fragmentation pattern was used to suggest the potential ways leading to this hydrolysis degradation product. This NP-HPLC-APCI-MS method development is described for the first time for the CyMe(4)BTBP and should provide separation methods regarding the analysis of polycyclic N-based extracting molecules and more generally for the investigation of the organic phase coming from liquid-liquid extraction processes used in nuclear fuel reprocessing. (C) 2011 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000295113600018,
author = {Nicolas, Gregory and Jankowski, Christopher K. and Lucas-Lamouroux, Christine and Bresson, Carole},
title = {Development of normal phase-high performance liquid chromatography-atmospherical pressure chemical ionization-mass spectrometry method for the study of 6,6 `-bis-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-benzo [1,2,4]-triazin-3-yl)-[2,2 `]-bipyridine hydrolytic degradation},
journal = {JOURNAL OF CHROMATOGRAPHY A},
year = {2011},
volume = {1218},
number = {37},
pages = {6369-6378},
doi = {10.1016/j.chroma.2011.07.003}
}
|
| "In-Situ Raman Observation of the First Step of Uranium Dioxide Weathering Exposed to Water Radiolysis" Guimbretiere G, Canizares A, Simon P, Tobon-Correa YA, Ammar MR, Corbel C and Barthe MF , SPECTROSCOPY LETTERS. Vol. {44}({7-8, SI}), pp. {570-573}. (2011). |
| Abstract: The effect of irradiation is a key point in the knowledge of the behavior of some compounds such as uranium-based ones. Regarding this topic, the authors developed an original in-situ Raman spectroscopy device coupled to a cyclotron ion beam. This original instrument allows observing the kinetics of uranium dioxide weathering by alpha radiolysis of water. The authors then observed that an altered layer made of Studtite and Schoepite phases grows linearly during the irradiation and extends for several hours after irradiation. Kinetics of production of some molecular species during radiolysis were also reported. |
BibTeX:
@article{ISI:000299995800025,
author = {Guimbretiere, G. and Canizares, A. and Simon, P. and Tobon-Correa, Y. A. and Ammar, M. R. and Corbel, C. and Barthe, M. F.},
title = {In-Situ Raman Observation of the First Step of Uranium Dioxide Weathering Exposed to Water Radiolysis},
journal = {SPECTROSCOPY LETTERS},
year = {2011},
volume = {44},
number = {7-8, SI},
pages = {570-573},
note = {Conference on Micro-Raman Spectroscopy and Luminescence Studies in the Earth and Planetary Sciences (CORALS), Spanish CSIC Cent Campus, Madrid, SPAIN, MAY 18-20, 2011},
doi = {10.1080/00387010.2011.610857}
}
|
| "Ion microbeam irradiation for radiobiology and radical chemistry: status and prospect" Khodja H, In COST CHEMISTRY CM0603-MELUSYN JOINT MEETING: DAMAGES INDUCED IN BIOMOLECULES BY LOW AND HIGH ENERGY RADIATIONS. Vol. {261}, (2011). |
| Abstract: Ion microbeams are commonly used to study local irradiation effects in living cells, as it has been established that ion beam irradiations can lead to deleterious changes in cells that are not struck directly by the microbeam. Such changes, which take place over distances long compared to the size of the irradiation spot and for times long compared to the time of irradiation, are collectively termed radiation-induced bystander effect or RIBE. Free-radical chemistry is frequently invoked to explain the RIBE but no unified model is available at present. Ion microbeams when coupled with advanced methods for observing free radicals are the tools of choice for investigating the chemistry and biological processes governing RIBE. |
BibTeX:
@inproceedings{ISI:000291672100012,
author = {Khodja, H.},
editor = {Gauduel, YA and HoueeLevin, C},
title = {Ion microbeam irradiation for radiobiology and radical chemistry: status and prospect},
booktitle = {COST CHEMISTRY CM0603-MELUSYN JOINT MEETING: DAMAGES INDUCED IN BIOMOLECULES BY LOW AND HIGH ENERGY RADIATIONS},
year = {2011},
volume = {261},
note = {COST Chemistry CM0603-MELUSYN Joint Meeting Damages Induced in Biomolecules by Low and High Energy Radiations, Paris, FRANCE, MAR 09-12, 2010},
doi = {10.1088/1742-6596/261/1/012012}
}
|
| "Radiolysis of astrophysical ice analogs by energetic ions: the effect of projectile mass and ice temperature" Pilling S, Duarte ES, Domaracka A, Rothard H, Boduch P and da Silveira EF , PHYSICAL CHEMISTRY CHEMICAL PHYSICS. Vol. {13}({35}), pp. {15755-15765}. (2011). |
| Abstract: An experimental study of the interaction of highly charged, energetic ions (52 MeV(58)Ni(13+) and 15.7 MeV (16)O(5+)) with mixed H(2)O:C(18)O(2) astrophysical ice analogs at two different temperatures is presented. This analysis aims to simulate the chemical and the physicochemical interactions induced by cosmic rays inside dense, cold astrophysical environments, such as molecular clouds or protostellar clouds as well at the surface of outer solar system bodies. The measurements were performed at the heavy ion accelerator GANIL (Grand Accelerateur National d'Ions Lourds) in Caen, France. The gas samples were deposited onto a CsI substrate at 13 K and 80 K. In situ analysis was performed by a Fourier transform infrared (FTIR) spectrometer at different fluences. Radiolysis yields of the produced species were quantified. The dissociation cross section at 13 K of both H(2)O and CO(2) is about 3-4 times smaller when O ions are employed. The ice temperature seems to affect differently each species when the same projectile was employed. The formation cross section at 13 K of molecules such as C(18)O, CO (with oxygen from water), and H(2)O(2) increases when Ni ions are employed. The formation of organic compounds seems to be enhanced by the oxygen projectiles and at lower temperatures. In addition, because the organic production at 13 K is at least 4 times higher than the value at 80 K, we also expect that interstellar ices are more organic-rich than the surfaces of outer solar system bodies. |
BibTeX:
@article{ISI:000294167700003,
author = {Pilling, Sergio and Duarte, Eduardo Seperuelo and Domaracka, Alicja and Rothard, Hermann and Boduch, Philippe and da Silveira, Enio F.},
title = {Radiolysis of astrophysical ice analogs by energetic ions: the effect of projectile mass and ice temperature},
journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},
year = {2011},
volume = {13},
number = {35},
pages = {15755-15765},
doi = {10.1039/c1cp20592g}
}
|
| "In situ UV-visible spectrum acquisition of Br(3)(-). Investigations of concentrated HBr aqueous solutions under 13-keV X-rays" Saffre D, Atinault E, Pin S, Renault JP, Hazemann JL and Baldacchino G, In COST CHEMISTRY CM0603-MELUSYN JOINT MEETING: DAMAGES INDUCED IN BIOMOLECULES BY LOW AND HIGH ENERGY RADIATIONS. Vol. {261}, (2011). |
| Abstract: Water radiolysis has been investigated by in situ and direct detection by using the scavenging method and 13-keV X-rays from ESRF synchrotron. By using a famous chemical system, concentrated hydrobromic acidic solutions over a range of concentrations (from 0.1 to 0.6 mole.dm(-3)), and real time absorption spectroscopy of Br(3)(-) around 266 nm, we aimed at evaluating the effect of 13-keV X-rays, below the ionization K-edge of Br, on the Br(-) oxidation yield value. The HO(center dot) scavenging time ranging in the picosecond scale is also taken into consideration going to the earliest initial yields. We have also observed the limit of use of N(2)O and air as saturation gas. The oxidation limitation also comes from the presence of H(3)O(+) in abundance giving birth of competitive reactions. The determination of the dose rate delivered to the solution has been performed by using the Fricke dosimeter system by following absorbance at 304 nm. The dose rate was 18.5 Gy.s(-1). |
BibTeX:
@inproceedings{ISI:000291672100013,
author = {Saffre, D. and Atinault, E. and Pin, S. and Renault, J. P. and Hazemann, J. L. and Baldacchino, G.},
editor = {Gauduel, YA and HoueeLevin, C},
title = {In situ UV-visible spectrum acquisition of Br(3)(-). Investigations of concentrated HBr aqueous solutions under 13-keV X-rays},
booktitle = {COST CHEMISTRY CM0603-MELUSYN JOINT MEETING: DAMAGES INDUCED IN BIOMOLECULES BY LOW AND HIGH ENERGY RADIATIONS},
year = {2011},
volume = {261},
note = {COST Chemistry CM0603-MELUSYN Joint Meeting Damages Induced in Biomolecules by Low and High Energy Radiations, Paris, FRANCE, MAR 09-12, 2010},
doi = {10.1088/1742-6596/261/1/012013}
}
|
| 2010 |
| "Radiolysis of the polyethylene/water system: Studies on the role of hydroxyl radical" Billamboz N, Grivet M, Foley S, Baldacchino G and Hubinois J-C, RADIATION PHYSICS AND CHEMISTRY., JAN, {2010}. Vol. {79}({1}), pp. {36-40}. (2010). |
| Abstract: The role of hydroxyl radical on polyethylene degradation under aqueous conditions has been studied. The reactivity of HO(center dot) towards PE is highlighted by pulse radiolysis experiments on a PE powder suspension in water using the thiocyanate competition technique. Infrared analysis of PE films irradiated in the presence of water is performed. Solutions have been either degassed with Ar, in order to remove O(2) which would react with the PE. or N(2)O which enhances the production of HO(center dot) radicals. Oxygenated groups and double bond groups created at the surface of PE are characterized using IR analysis, and the results for both saturated solution systems are compared. (C) 2009 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000272377300007,
author = {Billamboz, Nicolas and Grivet, Manuel and Foley, Sarah and Baldacchino, Gerard and Hubinois, Jean-Charles},
title = {Radiolysis of the polyethylene/water system: Studies on the role of hydroxyl radical},
journal = {RADIATION PHYSICS AND CHEMISTRY},
year = {2010},
volume = {79},
number = {1},
pages = {36-40},
doi = {10.1016/j.radphyschem.2009.08.016}
}
|
| "On the Use of Electrospray Ionization and Desorption Electrospray Ionization Mass Spectrometry for Bulk and Surface Polymer Analysis" Bonnaire N, Dannoux A, Pernelle C, Amekraz B and Moulin C, APPLIED SPECTROSCOPY., JUL, {2010}. Vol. {64}({7}), pp. {810-818}. (2010). |
| Abstract: Electrospray ionization (ESI) and desorption electrospray ionization (DESI) mass spectrometry were for the first time compared to investigate degradation products resulting from radiolysis of polyurethane (PUR) irradiated using accelerated electrons. First, DESI optimization was performed to obtain the best results in terms of sensitivity for surface polymer analysis. Then, a comparison was performed between DESI-MS and ESI-MS characterization of the degradation products of irradiated PUR with different doses up to 10 MGy. Similar results were obtained despite a lower sensitivity of DESI. Finally, DESI results obtained by direct surface analysis of irradiated PUR films as a function of depth were compared to bulk analysis results obtained by ESI. This comparison shows that degradation products of PUR are very comparable at the surface or within the polymer, confirming the radio-oxidation homogeneity. |
BibTeX:
@article{ISI:000279713500018,
author = {Bonnaire, Nicolas and Dannoux, Adeline and Pernelle, Christine and Amekraz, Badia and Moulin, Christophe},
title = {On the Use of Electrospray Ionization and Desorption Electrospray Ionization Mass Spectrometry for Bulk and Surface Polymer Analysis},
journal = {APPLIED SPECTROSCOPY},
year = {2010},
volume = {64},
number = {7},
pages = {810-818}
}
|
| "Photochemical processes observed during the reaction of superoxide reductase from Desulfoarculus baarsii with superoxide Re-evaluation of the reaction mechanism" Bonnot F, Houee-Levin C, Favaudon V and Niviere V, BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS., APR, {2010}. Vol. {1804}({4}), pp. {762-767}. (2010). |
| Abstract: Superoxide reductase SOR is an enzyme involved in superoxide detoxification in some microorganisms. Its active site consists of a non-heme ferrous center in an unusual [Fe(NHiS)(4) (SCys)(1)] square pyramidal pentacoordination that efficiently reduces superoxide into hydrogen peroxide. In previous works, the reaction mechanism of the SOR from Desulfoarculus baarsii enzyme, studied by pulse radiolysis, was shown to involve the formation of two reaction intermediates T1 and T2. However, the absorption spectrum of T2 was reported with an unusual sharp band at 6213 nm, very different from that reported for other SORs. In this work, we show that the sharp band at 625 nm observed by pulse radiolysis reflects the presence of photochemical processes that occurs at the level of the transient species formed during the reaction of SOR with superoxide. These processes do not change the stoichiometry of the global reaction. These data highlight remarkable photochemical properties for these reaction intermediates, not previously suspected for iron-peroxide species formed in the SOR active site. We have reinvestigated the reaction mechanism of the SOR from D. baarsii by pulse radiolysis in the absence of these photochemical processes. The T1 and T2 intermediates now appear to have absorption spectra similar to those reported for the Archaeoglobus fulgidus SOR enzymes. Although for some enzymes of the family only one transient was reported, on the whole, the reaction mechanisms of the different SORs studied so far seem very similar, which is in agreement with the strong sequence and structure homologies of their active sites. (C) 2009 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000275516500015,
author = {Bonnot, Florence and Houee-Levin, Chantal and Favaudon, Vincent and Niviere, Vincent},
title = {Photochemical processes observed during the reaction of superoxide reductase from Desulfoarculus baarsii with superoxide Re-evaluation of the reaction mechanism},
journal = {BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS},
year = {2010},
volume = {1804},
number = {4},
pages = {762-767},
doi = {10.1016/j.bbapap.2009.11.019}
}
|
| "The influence of iron on water radiolysis in cement-based materials" Bouniol P, JOURNAL OF NUCLEAR MATERIALS., AUG, {2010}. Vol. {403}({1-3}), pp. {167-183}. (2010). |
| Abstract: For the time being, assessing the H-2 source term generated by gamma irradiated cement-based materials consists of simulating the radiolysis of the pore liquid on the only elementary reactions relating to the decomposition of alkaline water. Such incomplete description does not take into account the impurities contained in the cement and leads to underestimate the production of H-2. Systematically present in cement materials, iron is likely to influence radiolysis by the disturbance induced on radical chemistry throughout the irradiation period. The faster reactivity of e(aq)(-) and OH center dot radicals on Fe(III) and Fe(II), respectively, than on H2O2 and H-2 is responsible for the lower recycling capability of the ``Allen's chain reaction'', allowing for H-2 to be preserved in a closed system. A critical review of reaction data about iron complexes (hydroxo-, peroxo-) is presented in order to build up an ``iron'' database. Radiolysis simulations in cement porewater in the presence of Fe(OH)(3) (considered as a model phase) show, as expected, an increase in the effective production of radiolytic H-2 and the co-existence of exotic valence Fe(IV) with Fe(II) and (III) during the irradiation period (gamma). (C) 2010 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000280896700023,
author = {Bouniol, P.},
title = {The influence of iron on water radiolysis in cement-based materials},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2010},
volume = {403},
number = {1-3},
pages = {167-183},
doi = {10.1016/j.jnucmat.2010.06.020}
}
|
| "H-2 formation by electron irradiation of SBA-15 materials and the effect of Cu-II grafting" Brodie-Linder N, Le Caer S, Alam MS, Renault JP and Alba-Simionesco C, PHYSICAL CHEMISTRY CHEMICAL PHYSICS. Vol. {12}({42}), pp. {14188-14195}. (2010). |
| Abstract: Measurement of H-2 production from electron irradiation (10 MeV) on SBA-15 materials has shown that adsorbed water is attacked preferentially. Silanol groups are only attacked when they are in the majority with respect to adsorbed water, however they are much less efficient at producing H-2. The comparison between water content before and after electron irradiation and the corresponding H-2 production indicates that water desorption is the main route to adsorbed water loss for SBA-15 materials. On the other hand, surface silanol groups are more susceptible to attack, leading to H-2 production when SBA-15 samples have undergone extensive thermal treatment. Electron irradiation of SBA-15-Cu materials has shown that the presence of Cu-II on the surface reduces and inhibits the production of H-2. This inhibiting power affects adsorbed water bonded to grafted copper but not surface silanol groups. |
BibTeX:
@article{ISI:000283262400037,
author = {Brodie-Linder, Nancy and Le Caer, Sophie and Alam, Mohammad Shahdo and Renault, Jean Philippe and Alba-Simionesco, Christiane},
title = {H-2 formation by electron irradiation of SBA-15 materials and the effect of Cu-II grafting},
journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},
year = {2010},
volume = {12},
number = {42},
pages = {14188-14195},
doi = {10.1039/c0cp00115e}
}
|
| "DIAMEX Solvent Behavior under Continuous Degradation and Regeneration Operations" Cames B, Bisel I, Baron P, Hill C, Rudloff D and Saucerotte B, In NUCLEAR ENERGY AND THE ENVIRONMENT. Vol. {1046}, pp. {255-269}. (2010). |
| Abstract: Industrial implementation of partitioning processes based on solvent extraction requires solvent recycling with constant separation and physicochemical properties. In nuclear applications, both radiolysis and acidic hydrolysis lead to degradation products which need to be removed from solvent before its recycling. The long term evolution of DIAMEX process solvent (0.65M DMDOHEMA HTP) under continuous degradation by acidic hydrolysis and gamma-radiolysis was studied in the laboratory-scale MARCEL, gamma-irradiation facility, with and without alkaline treatment process (AT). With AT, analyses of organic phase showed the accumulation of only one degradation product, MDOHEMA, probably responsible for the molybdenum accumulation observed. Distribution coefficients of Zr, Pd, Fe and Nd, surface tension, refraction index, settling time, viscosity, and density were constant during the tests. Furthermore, no catalytic effect of fission and corrosion products was observed. These studies were consolidated by comparative alpha- and gamma-radiolysis batch tests which showed that alpha-radiolysis and gamma-radiolysis led to the same degradation products. |
BibTeX:
@inproceedings{ISI:000292221500021,
author = {Cames, B. and Bisel, I. and Baron, P. and Hill, C. and Rudloff, D. and Saucerotte, B.},
editor = {Wai, CM and Mincher, BJ},
title = {DIAMEX Solvent Behavior under Continuous Degradation and Regeneration Operations},
booktitle = {NUCLEAR ENERGY AND THE ENVIRONMENT},
year = {2010},
volume = {1046},
pages = {255-269},
note = {238th Annual Meeting of the American-Chemical-Society, Washington, DC, AUG 16-20, 2009}
}
|
| "Infrared study of astrophysical ice analogues irradiated by swift nickel ions" Domaracka A, Seperuelo Duarte E, Boduch P, Rothard H, Ramillon JM, Dartois E, Pilling S, Farenzena LS and da Silveira EF, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS., OCT 1, {2010}. Vol. {268}({19}), pp. {2960-2963}. (2010). |
| Abstract: Water, carbon oxide, carbon dioxide, and ammonia ices are known to be pervasive constituents of the solar system and the interstellar medium. These ices and ice-covered surfaces are exposed to bombardment by energetic projectiles like photons, electrons, and ions. Laboratory experiments have been carried out to study the effects of such irradiation. However, there is a clear lack of information about the interaction of heavy ion components of solar/stellar wind and galactic cosmic rays (e.g. Fe) with ices in the key to GeV energy range. The objective of this work is to study the effects produced in astrophysical ices by highly charged nickel ions at relatively high energy (similar to 50-500 MeV) in the electronic energy loss regime, and to compare them with those produced by protons, photons, and electrons. Our results for CO2 and CO indicate that sputtering induced by heavy ions can be an important mechanism to desorb molecules in astrophysical environments. (C) 2010 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000282301100025,
author = {Domaracka, A. and Seperuelo Duarte, E. and Boduch, P. and Rothard, H. and Ramillon, J. M. and Dartois, E. and Pilling, S. and Farenzena, L. S. and da Silveira, E. F.},
title = {Infrared study of astrophysical ice analogues irradiated by swift nickel ions},
journal = {NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS},
year = {2010},
volume = {268},
number = {19},
pages = {2960-2963},
note = {15th International Conference of the Radiation Effects in Insulators, ITALY, AUG 30-SEP 04, 2009},
doi = {10.1016/j.nimb.2010.05.017}
}
|
| "Oxidizing dissolution of spent MOX47 fuel subjected to water radiolysis: Solution chemistry and surface characterization by Raman spectroscopy" Jegou C, Caraballo R, De Bonfils J, Broudic V, Peuget S, Vercouter T and Roudil D, JOURNAL OF NUCLEAR MATERIALS., APR 1, {2010}. Vol. {399}({1}), pp. {68-80}. (2010). |
| Abstract: The mechanisms of oxidizing dissolution of spent MOX fuel (MIMAS TU2(R)) subjected to water radiolysis were investigated experimentally by leaching spent MOX47 fuel samples in pure water at 25 degrees C under different oxidizing conditions (with and without external gamma irradiation); the leached surfaces were characterized by Raman spectroscopy. The highly oxidizing conditions resulting from external gamma irradiation significantly increased the concentration of plutonium (Pu(V)) and uranium (U(VI)) compared with a benchmark experiment (without external irradiation). The oxidation behavior of the plutonium-enriched aggregates differed significantly from that of the UO(2) matrix after several months of leaching in water under gamma irradiation. The plutonium in the aggregates appears to limit fuel oxidation. The only secondary phases formed and identified to date by Raman spectroscopy are uranium peroxides that generally precipitate on the surface of the UO(2) grains. Concerning the behavior of plutonium, solution analysis results appear to be compatible with a conventional explanation based on an equilibrium with a Pu(OH)(4(am)) phase. The fission product release - considered as a general indicator of matrix alteration - from MOX47 fuel also increases under external gamma irradiation and a change in the leaching mode is observed. Diffusive leaching was clearly identified, coinciding with the rapid onset of steady-state actinide concentrations in the bulk solution. (C) 2010 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000277333700009,
author = {Jegou, C. and Caraballo, R. and De Bonfils, J. and Broudic, V. and Peuget, S. and Vercouter, T. and Roudil, D.},
title = {Oxidizing dissolution of spent MOX47 fuel subjected to water radiolysis: Solution chemistry and surface characterization by Raman spectroscopy},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2010},
volume = {399},
number = {1},
pages = {68-80},
doi = {10.1016/j.jnucmat.2010.01.004}
}
|
| "Raman spectroscopy characterization of actinide oxides (U1-yPuy)O-2 Resistance to oxidation by the laser beam and examination of defects" Jegou C, Caraballo R, Peuget S, Roudil D, Desgranges L and Magnin M, JOURNAL OF NUCLEAR MATERIALS., OCT 30, {2010}. Vol. {405}({3}), pp. {235-243}. (2010). |
| Abstract: Structural changes in four (U1-yPuy)O-2 materials with very different plutonium concentrations (0 <= y <= 1) and damage levels (up to 110 dpa) were studied by Raman spectroscopy The novel experimental approach developed for this purpose consisted in using a laser beam as a heat source to assess the reactivity and structural changes of these materials according to the power supplied locally by the laser The experiments were carried out in air and in water with or without hydrogen peroxide As expected the material response to oxidation in air depends on the plutonium content of the test oxide At the highest power levels U3O8 generally forms with UO2 whereas no significant change in the spectra indicating oxidation is observed for samples with high plutonium content ((PuO2)-Pu-239) Samples containing 25 wt % plutonium exhibit intermediate behavior typified mainly by a higher-intensity 632 cm(-1) peak and the disappearance of the 1LO peak at 575 cm(-1) This can be attributed to the presence of anion sub-lattice defects without any formation of higher oxides The range of materials examined also allowed us to distinguish partly the chemical effects of alpha self-irradiation The results obtained with water and hydrogen peroxide (a water radiolysis product) on a severely damaged (PuO2)-Pu-238 specimen highlight a specific behavior observed for the first time (C) 2010 Elsevier B V All rights reserved |
BibTeX:
@article{ISI:000284303000003,
author = {Jegou, C. and Caraballo, R. and Peuget, S. and Roudil, D. and Desgranges, L. and Magnin, M.},
title = {Raman spectroscopy characterization of actinide oxides (U1-yPuy)O-2 Resistance to oxidation by the laser beam and examination of defects},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2010},
volume = {405},
number = {3},
pages = {235-243},
doi = {10.1016/j.jnucmat.2010.08.005}
}
|
| "Understanding the Redox-Induced Polymer Grafting Process: A Dual Surface-Solution Analysis" Mesnage A, Esnouf S, Jegou P, Deniau G and Palacin S, CHEMISTRY OF MATERIALS., DEC 14, {2010}. Vol. {22}({23}), pp. {6229-6239}. (2010). |
| Abstract: As recently reported, the Graftfast process is a grafting method that provides covalently grafted polymer films. It relies on the chemical reduction of diazonium salts by reducing agents in absence or presence of a vinylic monomer. Contrary to electroinduced methods delivering strongly grafted and stable polymer films such as cathodic electrografting (CE) of vinylic monomers (which requires drastic experimental conditions) or surface electroinitiated emulsion polymerization (SEEP), the Graftfast process provides strongly grafted polymer films on any type of materials (conductors, semiconductors, and insulators). Moreover, it is a fast one-step reaction occurring at atmospheric pressure, ambient air and room temperature in water, which makes it more suitable for applications than the slower ATRP-based methods. This article aims to complete the first paper on this process by giving preliminary answers to the question: How does the Graftfast process work? To achieve this mechanistic study, dual surface-solution analyses were performed. Both spontaneous and redox-induced grafting of polynitrophenylene-like (PNP) films and poly(hydroxyethyl) methacrylate (PHEMA) films were analyzed by infrared-attenuated total reflection (IR-ATR) and X-ray photoelectron spectroscopy (XPS) while the corresponding reactive solutions were studied by electronic paramagnetic resonance, EPR (spin-trapping method using 2-methyl-2-nitrosopropane MNP as spin-trapping agent). The EPR spectra and hyperfine structure of MNP adducts provide evidence of aryl radicals production, growing polymer chains radicals formation, and the existence of critical concentration values, leading to favorable grafting kinetics. |
BibTeX:
@article{ISI:000284975100006,
author = {Mesnage, Alice and Esnouf, Stephane and Jegou, Pascale and Deniau, Guy and Palacin, Serge},
title = {Understanding the Redox-Induced Polymer Grafting Process: A Dual Surface-Solution Analysis},
journal = {CHEMISTRY OF MATERIALS},
year = {2010},
volume = {22},
number = {23},
pages = {6229-6239},
doi = {10.1021/cm1014702}
}
|
| "Footprinting of Protein Interactions by Tritium Labeling" Mousseau G, Raffy Q, Thomas OP, Agez M, Thai R, Renault JP, Pin S, Ochsenbein F, Cintrat J-C and Rousseau B, BIOCHEMISTRY., MAY 25, {2010}. Vol. {49}({20}), pp. {4297-4299}. (2010). |
| Abstract: A new footprinting method for mapping protein interactions has been developed, using tritium as a radioactive label. As residues involved in an interaction are less labeled when the complex is formed, they can be identified via comparison of the tritium incorporation of each residue of the bound protein with that of the unbound one. Application of this footprinting method to the complex formed by the histone H3 fragment H3(122-135) and the protein hAsflA(1-156) afforded data in good agreement with NMR results. |
BibTeX:
@article{ISI:000277649200001,
author = {Mousseau, Guillaume and Raffy, Quentin and Thomas, Oliver P. and Agez, Morgane and Thai, Robert and Renault, Jean Philippe and Pin, Serge and Ochsenbein, Francoise and Cintrat, Jean-Christophe and Rousseau, Bernard},
title = {Footprinting of Protein Interactions by Tritium Labeling},
journal = {BIOCHEMISTRY},
year = {2010},
volume = {49},
number = {20},
pages = {4297-4299},
doi = {10.1021/bi100031a}
}
|
| "Radiolysis of water in nanoporous gold" Musat R, Moreau S, Poidevin F, Mathon MH, Pommeret S and Renault JP, PHYSICAL CHEMISTRY CHEMICAL PHYSICS. Vol. {12}({39}), pp. {12868-12874}. (2010). |
| Abstract: Nanoporous gold was used as a high specific surface material to describe the water radiolysis in the vicinity of metal surfaces. Porous gold monoliths were prepared by electrolytic dissolution of silver in Au-Ag alloys and characterized by small angle neutron scattering. The hydroxyl radical production under gamma irradiation was measured by benzoate scavenging in water confined in 50 nm porous gold or in silica glasses of similar pore size, and in bulk water. Whereas a silica interface induces minimal modifications to the HO(center dot) radical production with respect to bulk water, HO(center dot) production near gold is enhanced more than seven times on the short time scale, and almost completely suppressed by reaction with the metal on the long time scale. |
BibTeX:
@article{ISI:000282643900060,
author = {Musat, R. and Moreau, S. and Poidevin, F. and Mathon, M. H. and Pommeret, S. and Renault, J. P.},
title = {Radiolysis of water in nanoporous gold},
journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},
year = {2010},
volume = {12},
number = {39},
pages = {12868-12874},
doi = {10.1039/c0cp00967a}
}
|
| "Potential applications of sonochemistry in spent nuclear fuel reprocessing: A short review" Nikitenko SI, Venault L, Pflieger R, Chave T, Bisel I and Moisy P, ULTRASONICS SONOCHEMISTRY., AUG, {2010}. Vol. {17}({6, SI}), pp. {1033-1040}. (2010). |
| Abstract: The industrial treatment of spent nuclear fuel is based upon a hydrometallurgical process in nitric acid medium. In order to minimize the volume of radioactive waste it scorns interesting to generate the reactive species in situ in such solutions using ultrasonic irradiation without addition of salt-forming reagents. This review summarizes for the first time the versatile sonochemical processes with uranium, neptunium and plutonium in homogeneous nitric acid solutions and heterogeneous systems. The dissolution of refractory solids, ultrasonically driven liquid-liquid extraction and the sonochemical degradation of the volatile products of organic solvent radiolysis issued from PUREX process are considered. Also the guidelines for required further work to ensure successful application of the studied processes at industrial scale are discussed. (C) 2009 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000279625500010,
author = {Nikitenko, S. I. and Venault, L. and Pflieger, R. and Chave, T. and Bisel, I. and Moisy, P.},
title = {Potential applications of sonochemistry in spent nuclear fuel reprocessing: A short review},
journal = {ULTRASONICS SONOCHEMISTRY},
year = {2010},
volume = {17},
number = {6, SI},
pages = {1033-1040},
doi = {10.1016/j.ultsonch.2009.11.012}
}
|
| "Radiolysis of Water Confined in Porous Silica: A Simulation Study of the Physicochemical Yields" Ouerdane H, Gervais B, Zhou H, Beuve M and Renault JP, JOURNAL OF PHYSICAL CHEMISTRY C., JUL 29, {2010}. Vol. {114}({29}), pp. {12667-12674}. (2010). |
| Abstract: We investigate the radiolysis of liquid water confined in a porous silica matrix by means of an event-by-event Monte Carlo simulation of electron penetration in this composite system. We focus on the physical and physicochemical effects that take place in the picosecond range, before the radicals start to diffuse and react. We determine the radiolytic yields of the primary species for a system made of cylindrical pores filled with water over a wide range of pore radii R(C). We show that the relative position of the conduction band edge V(0) in both materials plays a major role in the radiolysis of composite systems. Due to its lower V(0) as compared to that of silica, water acts as a collector of low-energy electrons, which leads to a huge enhancement of the solvated electron yields for R(C) <= 100 nm. The confinement has also a marked effect on the spatial distribution of the radicals, which become isolated in a very large number of pores as R(C) decreases. |
BibTeX:
@article{ISI:000280070900041,
author = {Ouerdane, H. and Gervais, B. and Zhou, H. and Beuve, M. and Renault, J. -Ph.},
title = {Radiolysis of Water Confined in Porous Silica: A Simulation Study of the Physicochemical Yields},
journal = {JOURNAL OF PHYSICAL CHEMISTRY C},
year = {2010},
volume = {114},
number = {29},
pages = {12667-12674},
doi = {10.1021/jp103127j}
}
|
| "Radiolysis of H2O:CO2 ices by heavy energetic cosmic ray analogs" Pilling S, Duarte ES, Domaracka A, Rothard H, Boduch P and da Silveira EF, ASTRONOMY & ASTROPHYSICS., NOV-DEC, {2010}. Vol. {523}, (2010). |
| Abstract: An experimental study of the interaction of heavy, highly charged, and energetic ions (52 MeV Ni-58(13+)) with pure H2O, pure CO2 and mixed H2O:CO2 astrophysical ice analogs is presented. This analysis aims to simulate the chemical and the physicochemical interactions induced by heavy cosmic rays inside dense and cold astrophysical environments, such as molecular clouds or protostellar clouds. The measurements were performed at the heavy ion accelerator GANIL (Grand Accelerateur National d'Ions Lourds in Caen, France). The gas samples were deposited onto a CsI substrate at 13 K. In-situ analysis was performed by a Fourier transform infrared (FTIR) spectrometer at different fluences. Radiolysis yields of the produced species were quantified. The dissociation cross sections of pure H2O and CO2 ices are 1.1 and 1.9 x 10(-13) cm(2), respectively. For mixed H2O: CO2 (10:1), the dissociation cross sections of both species are about 1 x 10(-13) cm(2). The measured sputtering yield of pure CO2 ice is 2.2 x 10(4) molec ion(-1). After a fluence of 2-3 x 10(12) ions cm(-2), the CO2/CO ratio becomes roughly constant (similar to 0.1), independent of the initial CO2/H2O ratio. A similar behavior is observed for the H2O2/H2O ratio, which stabilizes at 0.01, independent of the initial H2O column density or relative abundance. |
BibTeX:
@article{ISI:000285346600080,
author = {Pilling, S. and Duarte, E. Seperuelo and Domaracka, A. and Rothard, H. and Boduch, P. and da Silveira, E. F.},
title = {Radiolysis of H2O:CO2 ices by heavy energetic cosmic ray analogs},
journal = {ASTRONOMY & ASTROPHYSICS},
year = {2010},
volume = {523},
doi = {10.1051/0004-6361/201015123}
}
|
| "Radiolysis of ammonia-containing ices by energetic, heavy, and highly charged ions inside dense astrophysical environments" Pilling S, Duarte ES, da Silveira EF, Balanzat E, Rothard H, Domaracka A and Boduch P, ASTRONOMY & ASTROPHYSICS., JAN, {2010}. Vol. {509}, (2010). |
| Abstract: Deep inside dense molecular clouds and protostellar disks, interstellar ices are protected from stellar energetic UV photons. However, X-rays and energetic cosmic rays can penetrate inside these regions triggering chemical reactions, molecular dissociation, and evaporation processes. We present experimental studies of the interaction of heavy, highly charged, and energetic ions (46 MeV (58)Ni(13+)) with ammonia-containing ices H(2)O:NH(3) (1:0.5) and H(2)O:NH(3):CO (1:0.6:0.4) in an attempt to simulate the physical chemistry induced by heavy-ion cosmic rays inside dense astrophysical environments. The measurements were performed inside a high vacuum chamber coupled to the IRRSUD (IR radiation SUD) beamline at the heavy-ion accelerator GANIL (Grand Accelerateur National d'Ions Lourds) in Caen, France. The gas samples were deposited onto a polished CsI substrate previously cooled to 13 K. In-situ analysis was performed by a Fourier transform infrared spectrometer (FTIR) at different fluences. The average values of the dissociation cross-section of water, ammonia, and carbon monoxide due to heavy-ion cosmic ray analogs are similar to 2 x 10(-13), 1.4 x 10(-13), and 1.9 x 10(-13) cm(2), respectively. In the presence of a typical heavy cosmic ray field, the estimated half life of the studied species is 2-3 x 10(6) years. The ice compaction (micropore collapse) produced by heavy cosmic rays seems to be at least 3 orders of magnitude higher than that produced by (0.8 MeV) protons. The infrared spectra of the irradiated ice samples exhibit lines of several new species including HNCO, N(2)O, OCN(-), and NH(4)(+). In the case of the irradiated H(2)O: NH(3): CO ice, the infrared spectrum at room temperature contains five bands that are tentatively assigned to vibration modes of the zwitterionic glycine (NH(3)(+) CH(2)COO(-)). |
BibTeX:
@article{ISI:000274159400098,
author = {Pilling, S. and Duarte, E. Seperuelo and da Silveira, E. F. and Balanzat, E. and Rothard, H. and Domaracka, A. and Boduch, P.},
title = {Radiolysis of ammonia-containing ices by energetic, heavy, and highly charged ions inside dense astrophysical environments},
journal = {ASTRONOMY & ASTROPHYSICS},
year = {2010},
volume = {509},
doi = {10.1051/0004-6361/200912274}
}
|
| "Structural characterisation of degradation products formed upon di-n-butyl phthalate radiolysis by high-performance liquid chromatography electrospray tandem mass spectrometry" Tintaru A, Labed V and Charles L, EUROPEAN JOURNAL OF MASS SPECTROMETRY. Vol. {16}({5}), pp. {595-603}. (2010). |
| Abstract: Structural characterisation of 15 degradation products, formed upon di-n-butyl phthalate (DBP) radiolysis, has been achieved using a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) coupling. The dissociation behaviour of protonated DBP was first established to be further used to characterise structural deviation in the degradation products. Based on accurate mass measurements, compounds shown by H PLC-MS analysis were all found to be DBP oxidation products, amongst which various sets of isomers could be distinguished. Collision-induced dissociation experiments performed on each electrosprayed molecule first allowed unambiguous definition of the location of the additional oxygen atoms; that is, in the alkyl branch or on the aromatic ring. Although location of the oxygen atom in the alkyl branches could not always be precisely determined, relative abundances of some product ions allowed oxygenated functions to be identified |
BibTeX:
@article{ISI:000282257200005,
author = {Tintaru, Aura and Labed, Veronique and Charles, Laurence},
title = {Structural characterisation of degradation products formed upon di-n-butyl phthalate radiolysis by high-performance liquid chromatography electrospray tandem mass spectrometry},
journal = {EUROPEAN JOURNAL OF MASS SPECTROMETRY},
year = {2010},
volume = {16},
number = {5},
pages = {595-603},
doi = {10.1255/ejms.1096}
}
|
| 2009 |
| "Ionization and fragmentation of water clusters by fast highly charged ions" Adoui L, Cassimi A, Gervais B, Grandin J-P, Guillaume L, Maisonny R, Legendre S, Tarisien M, Lopez-Tarifa P, Politis M-F, du Penhoat M-AH, Vuilleumier R, Gaigeot M-P, Tavernelli I, Alcami M and Martin F, JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS., APR 14, {2009}. Vol. {42}({7}), (2009). |
| Abstract: We study the dissociative ionization of water clusters by impact of 12 MeV/u Ni(25+) ions. Cold target recoil ion momentum spectroscopy (COLTRIMS) is used to obtain information about stability, energetics and charge mobility of the ionized water clusters. An unusual stability of the H(9)O(4)(+) ion is observed, which could be the signature of the so-called Eigen structure in gas-phase water clusters. From the analysis of coincidences between charged fragments, we conclude that charge mobility is very high and is responsible for the formation of protonated water clusters, (H(2)O)(n)H(+), that dominate the mass spectrum. These results are supported by Car-Parrinello molecular dynamics and time-dependent density functional theory simulations, which also reveal the mechanisms of such mobility. |
BibTeX:
@article{ISI:000264504900004,
author = {Adoui, L. and Cassimi, A. and Gervais, B. and Grandin, J.-P. and Guillaume, L. and Maisonny, R. and Legendre, S. and Tarisien, M. and Lopez-Tarifa, P. and Politis, M.-F. and du Penhoat, M.-A. Herve and Vuilleumier, R. and Gaigeot, M.-P. and Tavernelli, I. and Alcami, M. and Martin, F.},
title = {Ionization and fragmentation of water clusters by fast highly charged ions},
journal = {JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS},
year = {2009},
volume = {42},
number = {7},
doi = {10.1088/0953-4075/42/7/075101}
}
|
| "Tuning hydrogen production during oxide irradiation through surface grafting" Alam M, Miserque F, Taguchi M, Boulanger L and Renault JP, JOURNAL OF MATERIALS CHEMISTRY. Vol. {19}({24}), pp. {4261-4267}. (2009). |
| Abstract: Hydrogen production by radiolysis of water absorbed on solid is a major problem for nuclear waste management. In the present study, we demonstrate that controlling extreme surface properties of the irradiated material allows a direct tuning of the hydrogen production under irradiation. We achieve this control on a model system (silica fibers) using liquid phase atomic layer deposition (ALD) of titanium or zirconium oxide. The hydrogen production is strongly inhibited by the deposition of a subnanometric layer of titanium oxide, whereas it is amplified upon zirconium oxide grafting. |
BibTeX:
@article{ISI:000266797500029,
author = {Alam, Mohamad and Miserque, Frederic and Taguchi, Mitsumasa and Boulanger, Loic and Renault, Jean Philippe},
title = {Tuning hydrogen production during oxide irradiation through surface grafting},
journal = {JOURNAL OF MATERIALS CHEMISTRY},
year = {2009},
volume = {19},
number = {24},
pages = {4261-4267},
doi = {10.1039/b901936g}
}
|
| "Determination of the time-dependent OH-yield by using fluorescent probe. Application to heavy ion irradiation" Baldacchino G, Maeyama T, Yamashita S, Taguchi M, Kimura A, Katsumura Y and Murakami T, CHEMICAL PHYSICS LETTERS., JAN 22, {2009}. Vol. {468}({4-6}), pp. {275-279}. (2009). |
| Abstract: This Letter reports a sensitive method using HPLC-Fluorescence detection of *OH in liquid water under high-energy heavy ion irradiation. The coumarin-3-carboxylic-acid (3CCA) molecule was selected for probing *OH and providing the fluorescent 7-hydroxy-coumarin-3-carboxylic-acid (7OH-3CCA). Since the concentration limit achievable is better than 1 nM, the radiolytic yields were determined with a sensitivity of 2 x 10(9) mol/J for 4.8 GeV-(12)C(6+) of and 20 GeV-(40)Ar(18+) in the ns time range. They decrease with the linear energy transfer from 2.8 x 10(7) to 1.3 x 10(7) mol/J (C(6+) of 11 eV/nm) and 1.5 x 10(7) to 0.9 x 10(7) mol/J (Ar(18+) of 90 eV/nm) which is in agreement with the literature data. (C) 2008 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000262412100036,
author = {Baldacchino, G. and Maeyama, T. and Yamashita, S. and Taguchi, M. and Kimura, A. and Katsumura, Y. and Murakami, T.},
title = {Determination of the time-dependent OH-yield by using fluorescent probe. Application to heavy ion irradiation},
journal = {CHEMICAL PHYSICS LETTERS},
year = {2009},
volume = {468},
number = {4-6},
pages = {275-279},
doi = {10.1016/j.cplett.2008.12.006}
}
|
| "Statistical effects of dose deposition in track-structure modelling of radiobiology efficiency" Beuve M, Colliaux A, Dabli D, Dauvergne D, Gervais B, Montarou G and Testa E, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS., MAR, {2009}. Vol. {267}({6}), pp. {983-988}. (2009). |
| Abstract: Ion-induced cell killing has been reported to depend on the irradiation dose but also on the projectile parameters. In this paper we focus on two approaches developed and extensively used to predict cell survival in response to ion irradiation: the Local Effect Model and the Katz Model. These models are based on a track-structure description summarized in the concept of radial dose. This latter is sensitive to ion characteristics parameters and gives to both models the ability to predict some important radiobiological features for ion irradiations. Radial dose is however an average quantity, which does not include stochastic effects. These radiation-intrinsic effects are investigated by means of a Monte Carlo simulation of dose deposition. We show that both models are not fully consistent with the nanometric and microscopic dose deposition statistics. (C) 2009 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000265815200030,
author = {Beuve, M. and Colliaux, A. and Dabli, D. and Dauvergne, D. and Gervais, B. and Montarou, G. and Testa, E.},
title = {Statistical effects of dose deposition in track-structure modelling of radiobiology efficiency},
journal = {NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS},
year = {2009},
volume = {267},
number = {6},
pages = {983-988},
note = {7thTriennial International Symposium on Swift Heavy Ions in Matter, Lyon, FRANCE, JUN 02-05, 2008},
doi = {10.1016/j.nimb.2009.02.016}
}
|
| "Leaching of Plasticized PVC: Effect of Irradiation" Colombani J, Herbette G, Rossi C, Joussot-Dubien C, Labed V and Gilardi T, JOURNAL OF APPLIED POLYMER SCIENCE., MAY 5, {2009}. Vol. {112}({3}), pp. {1372-1377}. (2009). |
| Abstract: Highly irradiated (2-26 MGy) polyvinyl chloride (PVC) was leached in an alkaline solution to investigate the impact of high doses on the leaching process and on the nature of the leaching products. The results show that leaching is controlled by diffusion phenomena as described by Fick's second law. The apparent diffusion coefficient (D(a)) of plasticized PVC leaching products can be calculated for each sample. Irradiation at high dose causes D(a) to diminish; this can be attributed to cross-linking and grafting reactions occurring during irradiation. The material microstructure thus becomes less permeable during radiolysis, which slows down the migration of species. Organic products of leaching are plasticizers contained in plasticized PVC or their degradation products. The main organic leaching products are phthalic ions formed by the hydrolysis of phthalic esters in alkaline leaching solution. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 1372-1377, 2009 |
BibTeX:
@article{ISI:000264247300031,
author = {Colombani, J. and Herbette, G. and Rossi, C. and Joussot-Dubien, C. and Labed, V. and Gilardi, T.},
title = {Leaching of Plasticized PVC: Effect of Irradiation},
journal = {JOURNAL OF APPLIED POLYMER SCIENCE},
year = {2009},
volume = {112},
number = {3},
pages = {1372-1377},
doi = {10.1002/app.29612}
}
|
| "Radiolysis of solvents containing C5-BTBP: identification of degradation products and their dependence on absorbed dose and dose rate" Fermvik A, Berthon L, Ekberg C, Englund S, Retegan T and Zorz N, DALTON TRANSACTIONS. ({32}), pp. {6421-6430}. (2009). |
| Abstract: Solvents intended for the separation of trivalent actinides from trivalent lanthanides in spent nuclear fuel have been irradiated with gamma-radiation. The solvents initially contained 0.005 M C5-BTBP dissolved in either hexanol or cyclohexanone and they were exposed to doses up to 20 kGy. Identification of degradation products was done using atmospheric pressure chemical ionization-mass spectrometry (APCI-MS). Structures were suggested for a number of degradation products and the relative intensity of the peaks in the MS spectra was estimated. It was clear that the content of the original molecule, C5-BTBP, decreased with dose, while the content of the various degradation products increased. It was also shown that both the choice of diluent and the dose rate (Gy/h) affect the amount of degradation products formed. A degradation scheme was proposed for the radiolytic degradation of C5-BTBP. |
BibTeX:
@article{ISI:000268689000023,
author = {Fermvik, Anna and Berthon, Laurence and Ekberg, Christian and Englund, Sofie and Retegan, Teodora and Zorz, Nicole},
title = {Radiolysis of solvents containing C5-BTBP: identification of degradation products and their dependence on absorbed dose and dose rate},
journal = {DALTON TRANSACTIONS},
year = {2009},
number = {32},
pages = {6421-6430},
doi = {10.1039/b907084b}
}
|
| "Anion effect on radiochemical stability of room-temperature ionic liquids under gamma irradiation" Le Rouzo G, Lamouroux C, Dauvois V, Dannoux A, Legand S, Durand D, Moisy P and Moutiers G, DALTON TRANSACTIONS. ({31}), pp. {6175-6184}. (2009). |
| Abstract: Radiochemical stability of imidazolium-based ionic liquids constituted of the BuMeIm(+) cation and associated with four commonly used anions (X(-): Tf(2)N(-), TfO(-), PF(6)(-) and BF(4)(-)) has been investigated under gamma irradiation for high irradiation doses (up to 2.0 MGy). The anion effect has been examined by quantifying the radiolytic yields of disappearance for cation and anions and by identifying corresponding radiolysis products with several analytical techniques. On the one hand, a large number of radiolysis products are formed throughout the irradiation in ionic liquid solutions, resulting from reactions of primary generated species of cation and anion by indirect radiolysis. Primary generated species can react together throughout the irradiation by indirect radiolysis to form numerous radiolysis products in small quantities, indicating that several complex degradation pathways are involved for these radiation doses. This degradation pattern has been confirmed by identification of numerous gaseous radiolytic products. On the other hand, quantitative studies show that radiochemical stabilities of ionic liquids are in the same range of values as systems envisioned in nuclear fuel reprocessing with relatively low hydrogen yields. Indeed, this present work emphasizes the suitability of ionic liquids for applications in the nuclear fuel cycle. |
BibTeX:
@article{ISI:000268438800016,
author = {Le Rouzo, G. and Lamouroux, C. and Dauvois, V. and Dannoux, A. and Legand, S. and Durand, D. and Moisy, P. and Moutiers, G.},
title = {Anion effect on radiochemical stability of room-temperature ionic liquids under gamma irradiation},
journal = {DALTON TRANSACTIONS},
year = {2009},
number = {31},
pages = {6175-6184},
doi = {10.1039/b903005k}
}
|
| "Determination of hydroxyl rate constants by a high-throughput fluorimetric assay: towards a unified reactivity scale for antioxidants" Louit G, Hanedanian M, Taran F, Coffigny H, Renault JP and Pin S, ANALYST. Vol. {134}({2}), pp. {250-255}. (2009). |
| Abstract: We describe in this article the development of a new method for the determination of rate constants of reaction of the hydroxyl radical, generated by radiolysis of water, with almost any possible molecule. It has been designed to provide a fast and reliable screening of antioxidant banks using microplates. Our particular approach is based on the use of the coumarin molecule as a competitor against the tested molecules: after a fast pulse of low dose irradiation, the fluorescence of 7-hydroxycoumarin produced by the oxidation of coumarin is measured and is inversely proportional to the scavenging ability of the tested antioxidant. We have validated our protocol using 32 molecules whose rate constants with HO(center dot) had already been evaluated and found a good agreement between our rate constants and the latter ones. The scopes and limitations of our method, as well as those of other rate constant determination methods, are discussed. |
BibTeX:
@article{ISI:000262849700007,
author = {Louit, Guillaume and Hanedanian, Mikael and Taran, Frederic and Coffigny, Herve and Renault, Jean Philippe and Pin, Serge},
title = {Determination of hydroxyl rate constants by a high-throughput fluorimetric assay: towards a unified reactivity scale for antioxidants},
journal = {ANALYST},
year = {2009},
volume = {134},
number = {2},
pages = {250-255},
doi = {10.1039/b813871k}
}
|
| "Radiolytic oxidation of UO2 pellets doped with alpha-emitters (Pu-238/239)" Muzeau B, Jegou C, Delaunay F, Broudic V, Brevet A, Catalette H, Simoni E and Corbel C, JOURNAL OF ALLOYS AND COMPOUNDS., JAN 7, {2009}. Vol. {467}({1-2}), pp. {578-589}. (2009). |
| Abstract: To assess the impact of alpha radiolysis of water on the oxidative dissolution Of UO2 under anoxic conditions, two series of plutonium-doped samples (specific alpha activity 385 and 18 MBq g(UO2)(-1)) Were fabricated, characterized and leached in water of varying complexity (pure water, carbonated water, dissolved hydrogen). Given the very high reactivity of these samples in the presence of air and in order to minimize any prior surface oxidation, a strict experimental protocol was developed based on high-temperature annealing in Ar+4% H-2 With preleaching cycles. Failure to follow this protocol prevents absolute quantification of oxidation of the UO2 surface by water radiolysis in solutions. Preoxidation of the pellet surface can lead to uranium release in solution that is dependent on the alpha particle flux, revealing initial oxidation by radiolysis in air including potential traces of water. This makes difficult the accurate quantification of the radiolytic oxidation in water solutions. Controlling the initial surface condition of the samples finally allowed us to demonstrate that radiolytic oxidation in water-saturated media is governed by several threshold effects for which the main parameters are the sample alpha activity and the hydrogen concentration. (C) 2008 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000262412000106,
author = {Muzeau, B. and Jegou, C. and Delaunay, F. and Broudic, V. and Brevet, A. and Catalette, H. and Simoni, E. and Corbel, C.},
title = {Radiolytic oxidation of UO2 pellets doped with alpha-emitters (Pu-238/239)},
journal = {JOURNAL OF ALLOYS AND COMPOUNDS},
year = {2009},
volume = {467},
number = {1-2},
pages = {578-589},
doi = {10.1016/j.jallcom.2007.12.054}
}
|
| "Transient absorption measurement system using pulsed energetic ion" Taguchi M, Baldacchino G, Kurashima S, Kimura A, Sugo Y, Katsumura Y and Hirota K, RADIATION PHYSICS AND CHEMISTRY., DEC, {2009}. Vol. {78}({12}), pp. {1169-1174}. (2009). |
| Abstract: This article reports a highly sensitive transient absorbance measurement system using pulsed energetic ions. The ions were pulsed by a beam chopper, which was synchronized with the cyclotron, and accelerated to the desired energy around 18 MeV/u. H, He, C and Ne ions can be used for the transient absorption measurement. The optical system can measure an absorbance smaller than 1.0 x 10(-4) in the wavelength range of 400-740 nm. (C) 2009 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000271337100037,
author = {Taguchi, Mitsumasa and Baldacchino, Gerard and Kurashima, Satoshi and Kimura, Atsushi and Sugo, Yumi and Katsumura, Yosuke and Hirota, Koichi},
title = {Transient absorption measurement system using pulsed energetic ion},
journal = {RADIATION PHYSICS AND CHEMISTRY},
year = {2009},
volume = {78},
number = {12},
pages = {1169-1174},
note = {2nd Asia-Pacific Symposium on Radiation Chemistry, Waseda Univ, Int Conf Ctr, Tokyo, JAPAN, AUG 29-SEP 01, 2008},
doi = {10.1016/j.radphyschem.2009.05.019}
}
|
| 2008 |
| "Pulse radiolysis in water with heavy-ion beams. A short review" Baldacchino G, RADIATION PHYSICS AND CHEMISTRY., OCT-DEC, {2008}. Vol. {77}({10-12}), pp. {1218-1223}. (2008). |
| Abstract: This article presents a short review of the studies in radiation chemistry of liquid water with heavy ions, which have used pulse radiolysis methods during the last 20 years. The interests and the difficulties of developing this kind of experiment are depicted. The linear energy transfer (LET) effect is the main topic of these studies. The earliest effects close to the structure of the deposited energy can be observed directly by transient absorption spectroscopy by following the hydrated electron, the superoxide radical produced in the absence of molecular oxygen and the hydroxyl radical, which still requires the use of scavenger. Finally, the results can be compared to the heterogeneous chemical processes in the time range of 1 ns to 1 mu s described by Monte Carlo simulations. The absolute values of the radiolytic yields are still uncertain because of the dosimetry accuracy. The future aspects of the method are discussed in terms of new types of particle accelerators giving better time resolutions. (c) 2008 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000259798400020,
author = {Baldacchino, G.},
title = {Pulse radiolysis in water with heavy-ion beams. A short review},
journal = {RADIATION PHYSICS AND CHEMISTRY},
year = {2008},
volume = {77},
number = {10-12},
pages = {1218-1223},
note = {International Symposium on Charged Particle and Photon Interactions with Matter, Tokai, JAPAN, NOV 06-09, 2007},
doi = {10.1016/j.radphyschem.2008.05.033}
}
|
| "A model for the study of molecules radiochemical decomposition by actinides materials" Berlu L and Rosa G, In ACTINIDES 2008 - BASIC SCIENCE, APPLICATIONS AND TECHNOLOGY. Vol. {1104}, pp. {215-220}. (2008). |
| Abstract: The radiochemical decomposition of molecules in storage environment which could lead to the corrosion of container or the formation of dangerous gas mixtures is a critical problem for radioactive materials. The complexity of the chemical system makes numerical models necessary for the reproduction mechanisms and the prediction of phenomena. In this study, a mathematical model for the dose rate distribution in external medium surrounding an alpha emitter actinide material has been proposed. The model has been implemented in a Monte Carlo scheme. An evaluation of the dose rate in the surrounding medium as a function of the sample size was shown and a discussion of the expected reactivity was made. |
BibTeX:
@inproceedings{ISI:000258911500029,
author = {Berlu, Lilian and Rosa, Gaelle},
editor = {Shuh, DK and Chung, BW and AlbrechtSchmitt, T and Gouder, T and Thompson, JD},
title = {A model for the study of molecules radiochemical decomposition by actinides materials},
booktitle = {ACTINIDES 2008 - BASIC SCIENCE, APPLICATIONS AND TECHNOLOGY},
year = {2008},
volume = {1104},
pages = {215-220},
note = {Symposium on Actinides 2008 - Basic Science, Applications and Technology held at the 2008 MRS Spring Meeting, San Francisco, CA, MAR 25-28, 2008}
}
|
| "Stability of [MeBu3N][Tf2N] under gamma irradiation" Bosse E, Berthon L, Zorz N, Monget J, Berthon C, Bisel I, Legand S and Moisy P, DALTON TRANSACTIONS. ({7}), pp. {924-931}. (2008). |
| Abstract: The stability of the ionic liquid [MeBu3N][Tf2N], dry or after contact with water (where [MeBu3N](+) is the methyltributylammonium cation and [Tf2N](-) is the bistriflimide anion), was studied under Cs-137 gamma irradiation in argon and in air. In a quantitative study with an absorbed dose of 2 MGy this ionic liquid was highly stable regardless of the radiolysis conditions. The radiolytic disappearance yields determined by ESI-MS were -0.38 and -0.25 mu mol J(-1) for the cation and anion, respectively. ESI-MS, NMR, and liquid chromatography coupled with ESI-MS identified a large number of degradation products in very small quantities for the same dose. The cation radicals were formed by the loss of a Bu-lozenge group, the Me-lozenge group, or two H-lozenge atoms to form a double bond with the butyl chain. Radiolysis of the anion produced mainly F-lozenge and CF3 lozenge radicals. The anion radicals recombined with the cation to form a wide range of secondary degradation products regardless of the radiolysis conditions. |
BibTeX:
@article{ISI:000252979000012,
author = {Bosse, Emilie and Berthon, Laurence and Zorz, Nicole and Monget, Julie and Berthon, Claude and Bisel, Isabelle and Legand, Solene and Moisy, Philippe},
title = {Stability of [MeBu3N][Tf2N] under gamma irradiation},
journal = {DALTON TRANSACTIONS},
year = {2008},
number = {7},
pages = {924-931},
doi = {10.1039/b713661g}
}
|
| "Experiments to estimate gas intrusion in Callovo-oxfordian argillites" Boulin PF, Angulo-Jaramillo R, Daian J-F, Talandier J and Berne P, PHYSICS AND CHEMISTRY OF THE EARTH. Vol. {33}, pp. {S225-S230}. (2008). |
| Abstract: Gases, especially hydrogen, will be generated by corrosion and radiolysis of high radioactive waste containers in deep geological repositories. Pressure build up resulting from those long-term processes may create a risk of geological barrier fracturation and of potential creation of preferential pathways for radionuclide migration. Good knowledge of gas transfer mechanisms in the potential host rock formations is therefore necessary. The present work focuses on Callovo-oxfordian argillites from the Bure (Meuse, France) underground laboratory operated by Andra, the French national agency for radioactive waste management. Its goal is to understand the pore structure of that rock formation as a first step towards characterizing and modelling gas intrusion and transfer. Our approach was to use various techniques in combination. Firstly, mercury intrusion experiments were made. Besides supplying the classical pore size distribution curve, they bear some resemblance with the real-life problem since mercury (a non-wetting phase) invades the porous structure like a gas would. Secondly, the water vapor sorption curve was measured by submitting initially dry samples to atmospheres with increasing vapor content. Comparison of the mercury intrusion/water vapour sorption data sets yielded information on the connectivity of the pore structure. Thirdly, the gas permeability of dry argillites was measured in a specifically designed set-up, using helium as an acceptable (non-detonating) substitute for hydrogen. The main observation was the existence of a large Klinkenberg effect. Finally, all the available information was used to build and constrain a multi-scale models for the pore network using the XDQ technique. The resulting models were used to predict the properties of the material at various water saturation levels. (C) 2008 Elsevier Ltd. All rights reserved. |
BibTeX:
@article{ISI:000261743900027,
author = {Boulin, Pierre Francois and Angulo-Jaramillo, Rafael and Daian, Jean-Francois and Talandier, Jean and Berne, Philippe},
title = {Experiments to estimate gas intrusion in Callovo-oxfordian argillites},
journal = {PHYSICS AND CHEMISTRY OF THE EARTH},
year = {2008},
volume = {33},
pages = {S225-S230},
note = {3rd International Meeting on Clays in Natural and Engineered Barriers for Radioactive Waste Confinement, Lille, FRANCE, SEP 17-20, 2005},
doi = {10.1016/j.pce.2008.10.004}
}
|
| "A comprehensive model to describe radiolytic processes in cement medium" Bouniol P and Bjergbakke E, JOURNAL OF NUCLEAR MATERIALS., JAN 15, {2008}. Vol. {372}({1}), pp. {1-15}. (2008). |
| Abstract: Basic mechanisms controlling the radiolysis in cementitious matrices are reviewed in the specific context of the gamma irradiation, in closed system without upper vapour space, at 25 degrees C, with a pore solution representative of a Portland cement paste. A general survey of data corresponding to each phenomenological area is given, particularly with a list of reactions for alkaline medium and a revised description of equilibria related to calcium hydroxide. Simulations as a function of dose rate, liquid saturation in the porosity or initial amount of H-2 are carried out with the CHEMSIMUL code. They show the existence of several ways in the radiolysis regulation involving calcium peroxide octahydrate precipitation, a law of mass action through the bulk general system, or the particular activation of an Allen's type chain reaction. This latter seems faster in alkaline medium (pH > 13) where radicals H-center dot and OH center dot are, respectively, replaced by e(aq)(-) and O center dot-. Excepted when a strong reducing agent is initially present, 02 is normally produced by radiolysis and CaO2 center dot 8H(2)O cannot be responsible of its disappearance. (c) 2006 Published by Elsevier B.V. |
BibTeX:
@article{ISI:000253259700001,
author = {Bouniol, P. and Bjergbakke, E.},
title = {A comprehensive model to describe radiolytic processes in cement medium},
journal = {JOURNAL OF NUCLEAR MATERIALS},
year = {2008},
volume = {372},
number = {1},
pages = {1-15},
doi = {10.1016/j.jnucmat.2006.10.004}
}
|
| "Solid-state NMR characterization of a controlled-pore glass and of the effects of electron irradiation" Brunet F, Charpentier T, Le Caer S and Renault JP, SOLID STATE NUCLEAR MAGNETIC RESONANCE., JAN-FEB, {2008}. Vol. {33}({1-2}), pp. {1-11}. (2008). |
| Abstract: Controlled-pore glasses (CPGs) are silica-based materials which provide an adequate model system for a better understanding of the radiation chemistry of glasses, especially under nanoscopic confinement. This paper presents a characterization of a nanoporous CPG before and after electron irradiation using multinuclear solid-state magnetic resonance (NMR). H-1 MAS NMR has been used for studying the surface proton sites and it is observed that the irradiation leads to a dehydration of the material. Accordingly, concerning the silicon sites near the surface, the observed variation of the Q(4), Q(3) and Q(2) species from H-1-Si-29 CPMAS spectra shows an increase of the surface polymerization under irradiation, implying in majority a Q(2) to Q(3)/Q(4) conversion mechanism. Similarly, H-1-O-17 CPMAS measurements exhibit an increase of Si-O-Si groups at the expenses of Si-OH groups. In addition, modifications of the environment of the residual boron atoms are also put in evidence from B-11 MAS and MQMAS NMR These data show that MAS NMR methods provide sensitive tools for the characterization of these porous glasses and of the tiny modifications occurring under electron irradiation. (C) 2008 Elsevier Inc. All rights reserved. |
BibTeX:
@article{ISI:000255467200001,
author = {Brunet, F. and Charpentier, T. and Le Caer, S. and Renault, J. -P.},
title = {Solid-state NMR characterization of a controlled-pore glass and of the effects of electron irradiation},
journal = {SOLID STATE NUCLEAR MAGNETIC RESONANCE},
year = {2008},
volume = {33},
number = {1-2},
pages = {1-11},
doi = {10.1016/j.ssnmr.2007.12.001}
}
|
| "Irradiation of atactic polystyrene: Linear energy transfer effects" Ferry M, Ngono-Ravache Y, Picq V and Balanzat E, JOURNAL OF PHYSICAL CHEMISTRY B., SEP 4, {2008}. Vol. {112}({35}), pp. {10879-10889}. (2008). |
| Abstract: Atactic glassy polystyrene (PS) has been irradiated in anoxic conditions by electron and ion beams. The induced modifications were followed, in situ, by Fourier transform infrared spectroscopy (FTIR). In-film modifications and hydrocarbon gas release were followed. In-situ measurements allowed one to avoid any spurious oxidation of the films after irradiation and also permitted Studying in detail the evolution with dose of the FTIR spectra. The data were quantitatively analyzed, and we present a complete analysis of the effects of the Linear Energy Transfer (LET) on the radiation chemical yields of several radiation-induced modifications (alkynes, allenes, alkenes, benzene, and disubstituted benzenes). For a better understanding of the LET effects, the in-film modifications are compared to H-2 release data from the literature and to our measurements of hydrocarbon gaseous molecule yields obtained by us. The overall destruction yield becomes very significant at high LET, and the radiation sensitivity of this aromatic polymer merges with typical values of aliphatic polymers: the radiation resistance conferred at low LET to polystyrene by the phenyl side groups is lost at high LET. This loss of radiation resistance equally affects the aromatic and aliphatic moieties. Monosubstituted alkynes are created above a LET threshold, whereas the other radiation-induced modifications are observed in the whole LET range. Several observations indicate that the phenyl ring is broken at high LET. Comparison of the alkyne yield in PS, polyethylene, and polycarbonate as well as the formation of nitrile bonds in poly(vinylpyridine-co-styrene) are consistent with a cleavage of the phenyl ring as the prominent source of alkynes. As the competing damage mechanisms do not have the same LET evolution, the relative importance of a specific modification on the global damage depends on LET. Some (benzene and disubstituted benzenes) dominate at low LET, while others (in-film alkyne and acetylene release) dominate at high LET. |
BibTeX:
@article{ISI:000258800300020,
author = {Ferry, M. and Ngono-Ravache, Y. and Picq, V. and Balanzat, E.},
title = {Irradiation of atactic polystyrene: Linear energy transfer effects},
journal = {JOURNAL OF PHYSICAL CHEMISTRY B},
year = {2008},
volume = {112},
number = {35},
pages = {10879-10889},
doi = {10.1021/jp801865s}
}
|
| "Tritium release reduction and radiolysis gas formation" Gael B, Christophe D and Christophe S, FUSION SCIENCE AND TECHNOLOGY., JUL, {2008}. Vol. {54}({1}), pp. {205-208}. (2008). |
| Abstract: At CEA Valduc, the usual tritiated waste container is the steel drum. It allows good release reduction performance for middle activity waste but in some cases tritium outgassing from the waste drums is too high. It was decided to overpackage each drum in a tighter container called the over-drum. According to good safety practices it was also decided to measure gas composition evolution into the over-drum in order to defect hydrogen formation over time. After a few months, a significant release reduction was observed. Additionally there followed contamination reduction in the roof storage building rainwater. However hydrogen was also observed in some over-drums, in addition to other radiolysis products. Catalyst will be added to manage the hydrogen risk in the over-drums. |
BibTeX:
@article{ISI:000258206000046,
author = {Gael, Batifol and Christophe, Douche and Christophe, Sejournant},
title = {Tritium release reduction and radiolysis gas formation},
journal = {FUSION SCIENCE AND TECHNOLOGY},
year = {2008},
volume = {54},
number = {1},
pages = {205-208},
note = {8th International Conference on Tritium Science and Technology, Rochester, NY, SEP 16-21, 2007}
}
|
| "Effect of inorganic ligands and hydrogen peroxide on ThO(2) dissolution. Behaviour of Th(0.87)Pu(0.13)O(2) during leaching test" Hubert S, Heisbourg G, Dacheux N and Moisy P, INORGANIC CHEMISTRY., MAR 17, {2008}. Vol. {47}({6}), pp. {2064-2073}. (2008). |
| Abstract: The dissolution of ThO(2) powdered samples was examined in various conditions of pH and concentration of anions in the leachate. The first part of this paper describes the influence of pH on the dissolution of ThO(2) in both nitric and hydrochloric media. The partial order relative to the proton concentration and the apparent normalized dissolution rate constants were determined. The second part of the paper describes the influence of other ligands such as perchlorate, chloride, sulfate, and hydrogen peroxide on the dissolution kinetics (at pH 1). An increase of R(L) was observed correlatively with the increase of complexing affinity of the ligand with Th. While nitric and hydrochloric media, which are weakly complexing, lead to R(L) values with the same order of magnitude as those for perchlorate media, the presence of sulfate or peroxide in the leachate significantly enhances the dissolution of ThO(2). Consequently, the dissolution mechanism can be explained by the weakening of Th-O bonds through the formation of surface complexes at the solid/liquid interface, which enhance the detachment and thus accelerate the global dissolution. In addition, the dissolution of Th(0.87)Pu(0.13)O(2) solid solution was also examined. The increase of the dissolution kinetics of Th(0.87)Pu(0.13)O(2), in comparison with that of ThO(2), is considered to be caused by the presence of hydrogen peroxide formed by radiolysis of the leachate. Moreover, the redox properties of plutonium in acidic media, like disproportionation of Pu(IV) and Pu(V) and reduction of Pu(VI) and Pu(IV) in Pu(III) by H(2)O(2), probably increase the dissolution of plutonium. |
BibTeX:
@article{ISI:000253918000051,
author = {Hubert, Solange and Heisbourg, Guillaume and Dacheux, Nicolas and Moisy, Philippe},
title = {Effect of inorganic ligands and hydrogen peroxide on ThO(2) dissolution. Behaviour of Th(0.87)Pu(0.13)O(2) during leaching test},
journal = {INORGANIC CHEMISTRY},
year = {2008},
volume = {47},
number = {6},
pages = {2064-2073},
doi = {10.1021/ic702065z}
}
|
| "Oxidation of ruthenium oxide deposits by ozone" Mun C, Cantrel L and Madic C, RADIOCHIMICA ACTA. Vol. {96}({6}), pp. {375-384}. (2008). |
| Abstract: During a hypothetical severe accident on a nuclear Pressurized Water Reactor (PWR), the formation of highly radiotoxic RuO4(g) may occur in the reactor containment building, resulting from the interactions of ruthenium oxide deposits with the oxidising medium induced by air radiolysis. Consequently, there is a risk that the gaseous ruthenium tetroxide could be dispersed into the environment through containment leakages; therefore data concerning the behaviour of ruthenium oxide deposits is of primary importance for safety studies. An experiment has been designed to study the interactions of ruthenium oxide deposits with ozone, formed by air radiolysis. Experimental results have shown that the oxidation reaction leading to the formation of RuO4(g) occurred to a large extent. An oxidation kinetic rate law has been determined, in dry and moist air, for ruthenium deposited onto painted substrates, representative of the inner surfaces of PWR's. This law, combined with tetroxide stability data [1], will allow a first evaluation of ruthenium revolatilisation phenomenon, possibly occurring in the containment during a severe accident. |
BibTeX:
@article{ISI:000256831300007,
author = {Mun, C. and Cantrel, L. and Madic, C.},
title = {Oxidation of ruthenium oxide deposits by ozone},
journal = {RADIOCHIMICA ACTA},
year = {2008},
volume = {96},
number = {6},
pages = {375-384},
doi = {10.1524/ract.2008.1501}
}
|
| "Single and double reduction of C-60 in 2:1 gamma-cyclodextrin/[60]fullerene inclusion complexes by cyclodextrin radicals" Quaranta A, Zhang Y, Wang Y, Edge R, Navaratnam S, Land EJ and Bensasson RV, CHEMICAL PHYSICS., DEC 10, {2008}. Vol. {354}({1-3}), pp. {174-179}. (2008). |
| Abstract: Spectroscopic and chemical properties of gamma-CD center dot radicals, resulting from the abstraction by HO center dot radicals of hydrogen atoms, have been investigated using pulse radiolysis. The reactions of gamma-CD center dot radicals with C-60 in 2:1 gamma-CD/C-60 inclusion complexes have been Studied in aqueous solutions. It has been demonstrated that the gamma-CD center dot radicals are reducing species producing C-60(center dot-) monoanion radicals, as well as doubly reduced C-60(2-). well characterised by their absorption spectra in the near IR. The oxidation potential of gamma-CD center dot radical is estimated to be more negative than -390 mV vs. NHE. The kinetics of the C-60 reduction by gamma-CD center dot radicals have been determined and compared with kinetics by other reducing species including the solvated electron (e(aq)(-)) and CO2 center dot- radicals. It was observed that the method of preparation of the 2:1 gamma-CD/C-60 inclusion complexes modifies the C-60 reduction mechanism. (C) 2008 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000261980100021,
author = {Quaranta, Annamaria and Zhang, Yongmin and Wang, Yali and Edge, Ruth and Navaratnam, Suppiah and Land, Edward J. and Bensasson, Rene V.},
title = {Single and double reduction of C-60 in 2:1 gamma-cyclodextrin/[60]fullerene inclusion complexes by cyclodextrin radicals},
journal = {CHEMICAL PHYSICS},
year = {2008},
volume = {354},
number = {1-3},
pages = {174-179},
doi = {10.1016/j.chemphys.2008.10.014}
}
|
| "Advances in solid alanine radiolysis understanding" Raffi J, Talbi S, Dolo JM, Garcia T and Kister J, SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY., MAR, {2008}. Vol. {69}({3}), pp. {904-910}. (2008). |
| Abstract: To better understand the composite character of irradiated alanine ESR spectra, a comparative study of few simple amino acids is performed in order to identify the different radio-induced radicals and their proportions. A dedicated spin-trapping method coupled with High Performance Liquid Chromatography (HPLC) is developed and carried out on irradiated alanine, glycine and valine; labeled or not. This study leads us to obtain different isolated trapped radical spectra where hyperfine coupling constants could be evaluated. For alanine, only two species are identified with relative proportions around 97 and 3% in contradiction with recent published articles. The main species has a particularity on its hyperfine coupling constants when labeled carbons are used. Very high hyperfine coupling constants are observed with the carboxylic acid function carbon for the three studied amino acid. (C) 2007 Elsevier B.V. All rights reserved. |
BibTeX:
@article{ISI:000254770100032,
author = {Raffi, J. and Talbi, S. and Dolo, J. -M. and Garcia, T. and Kister, J.},
title = {Advances in solid alanine radiolysis understanding},
journal = {SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY},
year = {2008},
volume = {69},
number = {3},
pages = {904-910},
doi = {10.1016/j.saa.2007.05.040}
}
|
| "Hydrated electron production by reaction of hydrogen atoms with hydroxide ions: A first-principles molecular dynamics study" Renault JP, Vuilleumier R and Pommeret S, JOURNAL OF PHYSICAL CHEMISTRY A., JUL 31, {2008}. Vol. {112}({30}), pp. {7027-7034}. (2008). |
| Abstract: The solvated electron production by reaction between the H atom and the hydroxide anion was studied using Density Functional Theory based first-principles molecular dynamics. The simulation reveals a complex mechanism, controlled by proton transfers in the coordination sphere of the hydroxide and by the diffusion of the H atom in its solvent cavity. We formulate the hypothesis, based on a coupling between classical and first-principles molecular dynamics, that these two processes give rise to a lag time for the reaction that would explain the H atom extremely small reactivity compared to other radical species. Furthermore, the reaction observed gives an original insight in excess electron solvation. |
BibTeX:
@article{ISI:000257926900030,
author = {Renault, Jean Philippe and Vuilleumier, Rodolphe and Pommeret, Stanislas},
title = {Hydrated electron production by reaction of hydrogen atoms with hydroxide ions: A first-principles molecular dynamics study},
journal = {JOURNAL OF PHYSICAL CHEMISTRY A},
year = {2008},
volume = {112},
number = {30},
pages = {7027-7034},
doi = {10.1021/jp800269s}
}
|
| "Leaching of a zirconolite ceramic waste-form under proton and He(2+) irradiation" Tribet M, Toulhoat N, Moncoffre N, Jegou C, Leturcq G, Corbel C and Toulhoat P, RADIOCHIMICA ACTA. Vol. {96}({9-11}), pp. {619-624}. (2008). |
| Abstract: In the hypothesis of a nuclear waste geological disposal, zirconolite is a candidate host material for minor tri-and tetra-valent actinides arising from enhanced nuclear spent fuel reprocessing and partitioning. Its chemical durability has been studied here under charged particle-induced radiolysis (He(2+) and proton external beams) to identify possible effects on dissolution rates and mechanisms in pure water. Two experimental geometries have been used to evaluate the influence of the following parameters: solid irradiation and total deposited energy. Results on the evolution of the elemental releases due to the enhanced dissolution of the zirconolite Surface during charged particle-induced irradiation of water are presented. Under radiolysis, elemental releases are first kinetically controlled. When the titanium and the zirconium releases reach (or exceed) their corresponding hydroxide solubility limits, the zirconolite dissolution becomes thermodynamically controlled. |
BibTeX:
@article{ISI:000261096500016,
author = {Tribet, M. and Toulhoat, N. and Moncoffre, N. and Jegou, C. and Leturcq, G. and Corbel, C. and Toulhoat, P.},
title = {Leaching of a zirconolite ceramic waste-form under proton and He(2+) irradiation},
journal = {RADIOCHIMICA ACTA},
year = {2008},
volume = {96},
number = {9-11},
pages = {619-624},
note = {11th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere, Munich, GERMANY, AUG 26-31, 2007},
doi = {10.1524/ract.2008.1545}
}
|
