Search

Les universités génèrent d’importants flux de mobilité et la gestion des transports constitue un défi majeur pour leur fonctionnement. Cette recherche aborde cette problématique dans le cas de l’Université de Lausanne. Dans un premier temps, l’étude porte sur l’évolution du campus et de son accessibilité. Elle montre comment ce site suburbain a été relié au reste de l’agglomération et aborde les mesures prises pour réguler la mobilité. Deuxièmement, elle s’intéresse à la demande, soit aux choix modaux des 18’000 personnes qui travaillent et étudient à l’Université de Lausanne. Des enquêtes réalisées chaque année depuis 2005 permettent de mesurer les pratiques de mobilité et les différences au sein de la communauté universitaire. En conclusion sont esquissées les tendances qui influenceront à terme les flux de mobilité à destination du campus.

Two identical Phénix-type 15-15Ti steel pinlets each containing a 70 mm Pu0.3Zr0.7N fuel stack in a 1-bar helium atmosphere have been irradiated in the HFR Petten at medium high linear power (46-47 kW/m at BOL) and an average cladding temperature of 505 °C. The pins were irradiated to a plutonium burn-up of 9.7% (88 MWd/kgHM) in 170 full power days. Both pins remained fully intact. Post-irradiation examination performed at NRG and PSI showed that the overall swelling rate of the fuel was 0.92 vol-%/%FIHMA. Fission gas release was 5-6%, while helium release was larger than 50%. No fuel restructuring was observed, and only mild cracking. EPMA measurements show a burn-up increase toward the pellet edge of up to 4 times. All investigated fission products except to some extent the noble metals were found to be evenly distributed over the matrix, indicating good solubility. Local formation of a secondary phase with high Pu content and hardly any Zr was observed. A general conclusion of this investigation is that ZrN is a suitable inert matrix for burning plutonium at high destruction rates., QC 20151102

Fuels to be used in Accelerator Driven Systems dedicated to Minor Actinides transmutation can be described as highly innovative in comparison with those used in critical cores. Indeed, ADS fuels are not fertile, so as to improve the transmutation performance and they contain high volumetric concentrations (∼50%) of minor actinides and plutonium compounds. This unusual fuel composition results in high gamma and neutron emissions during its fabrication, as well as degraded performances under irradiation. Ceramic-Ceramic and Ceramic Metallic composite fuels consisting of particles of (Pu, MA)O2 phases dispersed in a magnesia or molybdenum matrix were investigated within the European Research programme for Transmutation, as driver fuels for a prospective 400MWth transmuter: the European Facility for Industrial Transmutation. Fuel performances and safety of preliminary core designs were evaluated to support the project. Out -of-pile as well as in-pile experiments were carried out to gain essential knowledge on properties and behaviour under irradiation of these types of fuel. This paper gives an overview of experimental results within the project., QC 20140909