The LAPA developed for re-corroding archaeological systems, originals setups, allowing to continue century old corrosion process in the lab and under labeled environments.
One way to get reliable knowledge about long term corrosion is to perform re-corrosion experiments. From natural sites, known for their chemical stability for years, corroded samples are picked up and then submitted to experiments. Discrimination between the changes during laboratory tests and the previous alteration in the natural media is performed using stables isotopes. Deuterium (heavy water) and gaseous oxygen 18 are commonly used in these experiments.
Due to the cost of the labeled compounds and the long duration of the experiments, the experimental devices are designed with a special care. Vacuum and high pressure solutions are applied to achieve the most perfect tightness. Stainless steel is the main material used and sometimes materials with low oxygen permeability are selected. The philosophy of the experimental process is to remove any oxygen trace (gaseous or dissolved) before introducing labeled compounds.
Later modifications revelation implies isotopic sensitive analysis by the mean of the nuclear microprobe. Practically, nuclear reactions are induced by the light ion scanning beam and reaction product detection precisely locates the stable isotope.
Maj : 08/10/2015 (1779)