Investigation of ion separation by microporous nanofiltration membranes

International audienc

Procédé de dissolution d'un oxyde métallique en présence d'un métal réducteur

Procédé de dissolution d'un oxyde métallique, dans une solution acide, caractérisé en ce que la solution acide a une concentration en acide comprise entre 0,001 M et 2M, et en ce qu'un métal réducteur, sous forme solide, est ajouté à la solution, le métal réducteur ayant un potentiel d'oxydoréduction inférieur à celui de l'oxyde métallique, pour favoriser la dissolution de l'oxyde métallique

Current collectors as reducing agent to dissolve active materials of positive electrodes from Li-ion battery wastes

International audienc

Synthesis and characterisation of carbon nanostructures substi-tuted with boron and/or nitrogen using electric arc plasma

International audienc

Impact of β-phase in TiAl alloys on mechanical properties after high temperature air exposure

International audienceIn this paper, the influence of high temperature air exposure on the tensile properties at room temperature and on the fatigue strength at high temperature of two TiAl alloys, is studied. The alloys, Ti-48Al-2Cr-2Nb (Ti-48-2-2), and Ti-44Al-4Nb-1Mo-0.1B (TNM-B1), both exhibit near-gamma microstructures, but the TNM-B1 alloy contains significant amounts of beta phase. Air exposure at high temperature (650-700°C, 500 h) induces significant loss of ductility, and decrease of fatigue strength at high temperature, in the case of the beta-containing TNM-B1 alloy, but not for the gamma-Ti-48-2-2 alloy. This indicates a potential influence of the presence of beta phase for embrittleme nt. Because embrittlement is believed to be the consequence of microstructure modifications in the sub-surface, first attempts have been performed to investigate these local phenomena. For this purpose, SEM, FIB, STEM-EDX and ACOM techniques have been employed. Destablilization of beta and, to a lesser extent, of gamma into alpha2, has been observed in the sub-surface of the TNM-B1 alloy. We interpret this as a consequence of oxygen diffusion during the high temperature air exposure, which would promote formation of alpha2 phase in which oxygen solubility is high, at the expenses of the beta and gamma phases of lower oxygen solubility

Synthesis of Boron-substituted Single-Wall Carbon Nanotubes by arc discharge

International audienc

Synthesis of Boron-doped Single Wall Carbon Nanotubes by arc discharge

International audienc

Synthèse par arc électrique et caractérisation de nanostructures carbonées substituées au bore et/ou l’azote

National audienc

Synthèse de nanotubes de carbone hétérogènes par arc électrique

National audienc