Experimental validation of VESTA 2.1

Depletion codes such as VESTA are used to calculate the evolution of a material subjected to radiation (be it neutrons or another type of particle) for a wide variety of applications in the fields of nuclear safety, radiation protection and environmental health safety. For these applications, experimental validation is paramount. In this paper we will describe the experimental validation of the latest version of VESTA using a set of 76 samples consisting of radiochemical assay data and decay heat measurements. We will describe the general calculation procedure that has been applied to determine the uncertainty on each individual nuclide measurement as well as the general tendencies and detailed results

Personality-dependent dispersal cancelled under predation risk

International audienc

Atmospheric trace compounds at a European coastal site—application to CO2, CH4 and COS flux determinations

International audienc

Exsolution of Ni Nanoparticles from A-Site-Deficient Layered Double Perovskites for Dry Reforming of Methane and as an Anode Material for a Solid Oxide Fuel Cell

International audienceExsolution is a promising technique to design metal nanoparticles for electrocatalysis and renewable energy. In this work, Ni-doped perovskites, (PrBa)MnNiO with = 0, 0.05, 0.1, and 0.2 (S-PBMNx), were prepared to design exsolution systems as solid oxide fuel cell anodes and for catalysis applications. X-ray diffraction and transmission electron microscopy (TEM) analyses demonstrated that correlating A-site deficiency with Ni content can effectively induce exsolution of all Ni under H atmosphere at ∼ 875 °C, yielding the reduced (exsolved) R-PBMNx materials. On heating the exsolution systems in air, metal incorporation in the oxide lattice did not occur; instead, the Ni nanoparticles oxidized to NiO on the layered perovskite surface. The lowest area-specific resistance (ASR) under wet 5% H/N in symmetrical cells was observed for -PBMN0.2 anode (ASR ∼ 0.64 Ω cm at 850 °C) due to the highest Ni particle density in the -PBMNx series. The best performance for dry reforming of methane (DRM) was also obtained for -PBMN0.2, with CH and CO conversion rates at 11 and 32%, respectively, and the highest production of H (37%). The DRM activity of -PBMN0.2 starts at 800 °C and is sustained for up to at least 5 h operation with little carbon deposition (0.017 g·gcat·h). These results clearly demonstrate that varying Ni-doping in layered double perovskite oxides is an effective strategy to manipulate the electrochemical performance and catalytic activity for energy conversion purposes