| | | | | | | webmail : intra-extra| Accès VPN| Accès IST| Contact
Univ. Paris-Saclay
Diffractomètres de "diffusion de neutrons aux petits angles" : PACE, PA20, PAxy, TPA
La structure sur des échelles de 1 à 100 nm
logo_tutelle logo_tutelle 

Le LLB dispose de 4 appareils de diffusions de neutrons aux petits angles (PA), de gauche à droite :

PACE
 
PA20
Small Angle Neutron Spectrometer
PAxy
Petits angles,
détecteur 2d XY
TPA
 
Très petits angles


 

Différentes architectures moléculaires étudiées par diffusion de neutrons aux petits angles.

 
#535 - Màj : 28/08/2019
Voir aussi
La diffusion neutronique est un outil précieux pour explorer les protéines, les édifices biologiques (complexes ADN-protéines), les cellules entières, l ’eau cellulaire.
This study investigates the long term behavior of glasses used for confinement of nuclear wastes. The results have been obtained from a fruitful collaboration between different CEA laboratories (LLB, LIONS, CEA Marcoule) and the Ecole Polytechnique. The corrosion process of the glasses by water creates at the glass surfaces, an alteration porous layer, hydrated and amorphous, called "gel".
The use of agricultural resources for industrial purposes will undoubtly be one of the major challenges of the 21 st century. Organic biosynthons used in chemistry should progressively replace those coming from fossil fuels. Our work on dispersions of fatty acids and hydroxylated derivatives forms part of these efforts in that it seeks to demonstrate the potential contribution of fatty acids (which may be extracted from plants) as a new class of surface active agents.
Following the synthesis by the ribosome, to carry out its biological function, a protein much fold into a single, well defined conformational state: the native state. Protein folding is thus the physico-chemical process by which a polypeptidic chain undergoes a structural change from an ensemble of coil like structure up to the unique structure encoded in its amino-acid sequence. This process is fascinating and remains one of the most challenging problems of structural biology.
The improvement of the mechanical properties of polymer films by inclusion of mineral particles is a well known industrial practice used since the end of the XIX century. A classical example is the rubber industry for which the addition of carbon black as fillers permits to increase the elastic modulus of the pneumatics. Nevertheless, the mechanisms which govern the reinforcement properties are still not completely described by experiments and theory.
P. Guenoun, C. Blot
See the PhD position opened in 2014 about this subject http://iramis.cea.fr/Pisp/patrick.guenoun/Greenmembranes.html Phase separation of polymer solution, induced by an abrupt quench in temperature, leads to a macroscopic segregation of phases. The growth of the phases and the associated structures when time elapses since the beginning of the quench are still badly known for hydrosoluble polymer solutions.

 

Retour en haut