Interaction of high energy protons in nuclear emulsions loaded with b 10 and LiF

An experiment is proposed to expose nuclear emulsions loaded with B{sup 10} and LiF to high energy protons at 100 GeV, 150 GeV and 200 GeV. The purposes are: (i) to measure the total cross-sections at these incident energies, (ii) to investigate charged multiplicity as a function of energy, (iii) to investigate the angular distribution and development of hadron showers in collisions of protons with nuclei

Purification of Uranium from acidic liquid wastes and ore solutions by selective hybrid materials

International audienc

The effect of pore diameter in the arrangement of chelating species grafted onto silica surfaces with application to uranium extraction

International audienc

DAMPING IDENTIFICATION IN MULTI-DEGREE-OF-FREEDOM SYSTEMS VIA A WAVELET-LOGARITHMIC DECREMENT--PART 1: THEORY

International audienceA wavelet-based formula similar to the logarithmic decrement formula is introduced to estimate damping in multi-degree-of-freedom systems from time-domain responses. Both analytical and numerical approaches are investigated

Uranium adsorption from sulfuric acid media using silica materials functionalised with amide and phosphorous ligands

International audienceVarious functionalised silica materials have been investigated as uranium extractants from sulfuric acid solutions. Silica was grafted with zero, one or two amido and phosphonate groups either directly or by peptide coupling. The role of the residual functions (silanol, amine and amide) was evaluated. Our results show that the uranium extraction efficiency of materials bearing residual Ol or Am groups may be affected by the presence of molybdenum. Comparing the performance of materials with different numbers of phosphonic acids on the phosphonate group revealed that only those with a monoacid function extract uranium efficiently. Among these materials, those with a diamido phosphonate ligand were more efficient than those with a monoamido phosphonate function. Adjusting the length and steric hindrance of the alkyls chains of the amido and the phosphonate group, the best extraction capacity and selectivity versus iron was achieved with a butyl group on the phosphonate and an ethyl group on the ternary amide of the diamido phosphonate ligand. Finally, the (ligand)-(U) ratio was found not to vary with bridge length between the carbamoyl monophosphonate extracting group and the amidopropyl anchor to the silica, suggesting that the extraction mechanism remains unchanged

Élaboration de silices hybrides pour la récupération de l'uranium

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