Thermodynamic assessment of the palladium–selenium (Pd–Se) system

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Experimental contribution to the corium thermodynamic modelling – The U–Zr–Al–Ca–Si–O system

International audienceDuring a severe accident in a nuclear reactor, extreme temperatures may be reached (T>2500 K). In these conditions, the nuclear fuel may react with the Zircaloy cladding and then with the steel vessel, forming a mixture of solid-liquid phases called in-vessel corium. In the worst scenario, this mixture may penetrate the vessel and reach the concrete underneath the reactor. In order to develop the TAF-ID thermodynamic database (www.oecd-nea.orgiscienceitaf-id) on nuclear fuels and to predict the high temperature behaviour of the corium + concrete system, new high temperature thermodynamic data are needed. The LM2T at CEA Saclay centre started an experimental campaign of phase equilibria measurements at high temperature (up to 2600 K) on interesting corium sub-systems. In particular, a heat treatment at 2500 K has been performed on two prototypic ex-vessel corium samples (within the U-Zr-Al-Ca-Si-O system) with different amounts of CaO and SiO2. The results show that depending on the SiO2-content, the final configuration of the samples can be significantly different. The sample with the higher CaO-content showed a dendritic structure representative of a single quenched liquid phase, whilst the sample richer in SiO2 exhibited a microstructure which suggests the presence of a liquid miscibility gap. Furthermore a new laser heating setup has been conceived. This technique allows very high temperature measures (T > 3000 K) limiting the interactions between the sample and the surroundings. (C) 2016 Elsevier Ltd. All rights reserved

Experimental study and thermodynamic modelling of corium mixtures Application to severe accidents in Pressurized Water Reactors

International audienceDuring a severe accident in a nuclear reactor, extreme temperatures may be reached (T > 2500 K). In these conditions, the nuclear fuel may react with the Zircaloy cladding and then with the steel vessel, forming a mixture of solid-liquid phases called in-vessel corium. In the worst scenario, this mixture may pierce the vessel and reach the concrete underneath the reactor. In the framework of the development of the TAF-ID thermodynamic database (www.oecd-nea.org/science/taf-id) on nuclear fuel and to predict the high temperature behaviour of the corium+concrete system, new high temperature thermodynamic data are needed. The LM2T at CEA Saclay centre started an experimental campaign of measure of phase equilibria at high temperature (up to 2400 K) on interesting corium sub-systems. Furthermore a new laser heating setup has been conceived. This technique allows very high temperature measures (T>3000 K) limiting the interactions between the sample and the surroundings. New phase equilibria data on the U-Zr-O system and on the U-Zr-Al-Ca-Si-O system will be presented. Moreover original melting temperature data on the PuO2-UO2-ZrO2 system obtained in collaboration with the JRC-ITU, will be also shown

Homicide et schizophrénie : à propos de 14 cas de schizophrénie issus d'une série de 210 dossiers d'expertises psy-chiatriques pénales pour homicide

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Thermodynamic study of (U-Pu-Zr-O-Fe) corium system

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Analytical characterisation of nuclear accident corium

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