Publications associées à Hexafluorure d'uranium

Systematic investigations of uranium carbide composites oxidation from micro- to nano-scale: Application to waste disposal

The production of radioisotope beams at the ISOLDE (Isotope Separator OnLine DEvice) facility at CERN is achieved by irradiating target materials (e.g. uranium carbides and metal foils) with protons. The materials are usually operated at temperatures above ...

EPFL2021

Design, synthesis, reactivity, and magnetic properties of uranium based oxide and nitride complexes

Luciano Barluzzi

The activation of small molecules is a paramount challenge in modern chemistry. The use of cheap and abundant molecules such as N2, H2, CO2, or CO as energy supplies or as precursors for fine chemicals production is highly desirable. In particular, the onl ...

EPFL2021

Nanoscale mechanism of UO2 formation through uranium reduction by magnetite

Rizlan Bernier-Latmani, Barbora Bártová, Thomas La Grange, Zezhen Pan

Uranium (U) is a ubiquitous element in the Earth's crust at similar to 2 ppm. In anoxic environments, soluble hexavalent uranium (U(VI)) is reduced and immobilized. The underlying reduction mechanism is unknown but likely of critical importance to explain ...

Nature Research2020

Structural Snapshots of Cluster Growth from {U6 } to {U38 } During the Hydrolysis of UCl4

Marinella Mazzanti, Farzaneh Fadaei Tirani, Lucile Sylvie Danielle Chatelain, Radmila Faizova

Herein we report the assembly of large uranium(IV) clusters with novel nuclearities and/or shapes from the controlled hydrolysis of UCl4 in organic solution and in the presence of the benzoate ligands. {U6}, {U13}, {U16}, {U24}, {U38} oxo and oxo/hydroxo c ...

Wiley-VCH Verlag GmbH2019

The underappreciated role of nonvolatile cations in aerosol ammonium-sulfate molar ratios

Athanasios Nenes, Hairun Guo

Overprediction of fine-particle ammonium-sulfate molar ratios (R) by thermodynamic models is suggested as evidence for interactions with organic constituents that inhibit the equilibration of gas-phase ammonia with aerosol sulfate and questions the equilib ...

Copernicus Publications2018

Synthesis and Characterization of a Water Stable Uranyl(V) Complex

Rosario Scopelliti, Radmila Faizova, Marinella Mazzanti, Anne-Sophie Chauvin

We have identified a polydentate aminocarboxylate ligand that stabilizes uranyl(V) in water. The mononuclear [UO2(dpaea)]X, (dpaeaH2 = Bis(pyridyl-6-methyl-2-carboxylate)-ethylamine; X = CoCp2*+ or X = K(2.2.2.cryptand) complexes have been isolated from an ...

2018

Microbial communities associated with uranium in-situ recovery mining process are related to acid mine drainage assemblages

Rizlan Bernier-Latmani, Pierre Rossi, Luiz Felippe De Alencastro, Thomas Coral

A large fraction (47%) of the world's uranium is mined by a technique called “In Situ Recovery” (ISR). This mining technique involves the injection of a leaching fluid (acidic or alkaline) into a uranium-bearing aquifer and the pumping of the resulting sol ...

2018

Modelling of fuel fragmentation, relocation and dispersal during Loss-of-Coolant Accident in Light Water Reactor

Vladimir Vladimirov Brankov

Recent LOCA tests with high burnup fuel at the OECD Halden Reactor Project and at Studsvik demonstrated the susceptibility of the fuel to fragment to small pieces, to relocate and possibly cause a hot-spot effect and to be dispersed in the event of claddin ...

EPFL2017

Heterometallic Fe-2(II)-U-V and Ni-2(II)-U-V Exchange-Coupled Single-Molecule Magnets: Effect of the 3d Ion on the Magnetic Properties

Marinella Mazzanti, Lucile Sylvie Danielle Chatelain

Uranium-based compounds have been put forward as ideal candidates for the design of single-molecule magnets (SMMs) with improved properties, but to date, only two examples of exchange-coupled 3d-5f SMM containing uranium have been reported and both are bas ...

Wiley-Blackwell2015

Speciation and reactivity of uranium products formed during in situ bioremediation in a shallow alluvial aquifer

Rizlan Bernier-Latmani, Elena Suvorova Buffat, Daniel Scott Alessi

In this study, we report the results of in situ U(VI) bioreduction experiments at the Integrated Field Research Challenge site in Rifle, Colorado, USA. Columns filled with sediments were deployed into a groundwater well at the site and, after a period of c ...

Amer Chemical Soc2014

Biogeochemical controls on the product of microbial U(VI) reduction

Rizlan Bernier-Latmani, Daniel Scott Alessi, Malgorzata Alicja Stylo, Paul Pao-Yun Shao

Biologically mediated immobilization of radio-nuclides in the subsurface is a promising strategy for the remediation of uranium-contaminated sites. During this process, soluble U(VI) is reduced by indigenous microorganisms to sparingly soluble U(TV). The c ...

Amer Chemical Soc2013

Single- and Two-Phase Flow Modeling for Coupled Neutronics/Thermal-Hydraulics Transient Analysis of Advanced Sodium-Cooled Fast Reactors

Aurélia Chenu

Nuclear power is nowadays in the front rank as regards helping to meet the growing worldwide energy demand while avoiding an excessive increase in greenhouse gas emissions. However, the operating nuclear power plants are mainly thermal-neutron reactors and ...

EPFL2011

Non-uraninite products of microbial U(VI) reduction

Rizlan Bernier-Latmani, Elena Suvorova Buffat, Harish Veeramani, Jonathan Sharp, Elena Cristina Dalla Vecchia, Nicholas Wigginton

A promising remediation approach to mitigate subsurface uranium contamination is the stimulation of indigenous bacteria to reduce mobile U(VI) to sparingly soluble U(IV). The product of microbial uranium reduction is often reported as the mineral uraninite ...

2010

Enhanced ammonia oxidation on BDD induced by inhibition of oxygen evolution reaction

Christos Comninellis, Agnieszka Kapalka, Nina-Luisa Michels

Electrochemical oxidation of ammonia (NH3 and NH4+) on boron-doped diamond (BDD) electrode was studied using differential electrochemical mass-spectrometry (DEMS) and chronoamperometry. Electro-oxidation of ammonia induces inhibition of the oxygen evolutio ...

Elsevier2010

Modeling U(VI) biomineralization in single- and dual- porosity porous media

David Andrew Barry

Uranium extraction, processing and storage have resulted in a legacy of uranium-contaminated groundwater aquifers worldwide. An emerging remediation technology for such sites is the in situ immobilization of uranium via biostimulation of dissimilatory meta ...

American Geophysical Union2008