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Concept

Affinage (métallurgie)

Publications associées (22)

Development of Cyclopentadienylcobalt(III) Catalyzed Asymmetric C-H Functionalizations

Kristers Ozols

Transition metal catalyzed C-H activation plays a major role in modern organic chemistry, affording mild, selective and atom-efficient protocols. Most of current developments in the field rely on the use of several precious metals. As a consequence, an int ...

EPFL2022

Additive manufacturing of a precious bulk metallic glass

Roland Logé, Jamasp Jhabvala, Antonia Neels, Navid Sohrabi, Güven Kurtuldu, Annapaola Parrilli

For the first time, a high-density amorphous and crack-free bulk metallic glass (BMG) based on a precious metal (PdCuNiP) was produced via additive manufacturing (AM). Laser powder-bed fusion (LPBF) was used for the fabrication of the samples, and led to a ...

2021

Alkynyl triazenes enable divergent syntheses of 2-pyrones

Kay Severin, Nicolai Cramer, Carl Thomas Bormann, Jin Fay Tan

The 2-pyrone motif occurs frequently in bioactive natural products and is appreciated as synthetic intermediates. However, only few methods allow for diversifying functional group modifications on this relevant heterocycle. The distinct properties of 1-alk ...

2021

Shape Engineering of Metal-Organic Frameworks via MOF@Polymer Composite Fabrication

Bardiya Valizadeh

Metal-organic frameworks (MOFs) are a fascinating class of porous materials that have become the subject of research owing to their unique characteristics such as high surface areas, low densities, and structural tunability. Recently, the research has been ...

EPFL2020

Synthetic methodologies for C-C and C-N bond formation involving alkyl radicals

Guido Barzanò

C-C and C-N bonds are some of the most common structures in molecules ranging from drugs to catalysts and to food additives. Many coupling reactions were developed to form these types of bonds with excellent selectivity and good performance. Still, the syn ...

EPFL2020

Activation of small molecules promoted by multimetallic complexes supported by redox active ligands

Davide Toniolo

The activation of small molecule is a topic of high current interest. A variety of homogeneous end heterogeneous catalysts have been studied to be able to promote chemical transformation of industrial relevance under mild condition and therefore decrease t ...

EPFL2020

Construction of MOF/Polymer Composites for Metal Ion Capture

Daniel Teav Sun

Metal ion capture is of environmental and economic significance. The industrial revolutions have discharged increasing amounts of heavy and precious metals into complex water sources. The key is that these types of metal ions tend to be at trace amounts in ...

EPFL2020

Deposition of impurity metals during campaigns with the JET ITER-like Wall

Olivier Sauter, Richard Pitts, Ambrogio Fasoli, Stefano Coda, Basil Duval, Henri Weisen, Yves Martin, Yann Camenen, Jan Horacek, Javier García Hernández, Duccio Testa, Marco Wischmeier, Nicola Vianello, Mikhail Maslov, Patrick Blanchard, Alessandro Pau, Davide Galassi, Antonio José Pereira de Figueiredo, Liang Yao, Dalziel Joseph Wilson, Cristian Sommariva, Jonathan Graves, Federico Nespoli, Hamish William Patten, Samuel Lanthaler, David Pfefferlé, Jonathan Marc Philippe Faustin

Post mortem analysis shows that mid and high atomic number metallic impurities are present in deposits on JET plasma facing components with the highest amount of Ni and W, and therefore the largest sink, being found at the top of the inner divertor. Source ...

Elsevier2019

Efficient cleavage of aryl ether C–O linkages by Rh–Ni and Ru–Ni nanoscale catalysts operating in water

Paul Joseph Dyson, Vassily Hatzimanikatis, Duncan Thomas Lindsay Alexander, Ning Yan, Georgios Savoglidis, Antoine Philippe Van Muyden, Sviatlana Siankevich, Safak Bulut

Bimetallic Ru–Ni and Rh–Ni nanocatalysts coated with a phase transfer agent efficiently cleave aryl ether C–O linkages in water in the presence of hydrogen. For dimeric substrates with weaker C–O linkages, i.e. α-O-4 and β-O-4 bonds, low loadings of the pr ...

2018

Design of Separated Element Reflector Experiments in CROCUS: PETALE

Andreas Pautz, Mathieu Hursin, Vincent Pierre Lamirand, Pavel Frajtag, Daniel Jerôme Siefman

The present article describes the preliminary design studies for PETALE (Programme d'Etude en Transmission de l'Acier Lourd et ses Elements), an oncoming experimental program in the CROCUS reactor. Within the framework of the Venus-Eole-Proteus collaborati ...

ASTM INTERNATIONAL2018

Densely Packed, Ultra Small SnO Nanoparticles for Enhanced Activity and Selectivity in Electrochemical CO2 Reduction

Xile Hu, Jeremy Luterbacher, Florent Emmanuel Héroguel, Jun Gu

Controlling the selectivity in electrochemical CO2 reduction is an unsolved challenge. While tin (Sn) has emerged as a promising non‐precious catalyst for CO2 electroreduction, most Sn‐based catalysts produce formate as the major product, which is less des ...

Wiley-VCH Verlag GmbH2018

A copper nickel mixed oxide hole selective layer for Au-free transparent cuprous oxide photocathodes

Michael Graetzel, Jingshan Luo, Matthew Thomas Mayer, Marcel Roland Schreier, Ludmilla Steier, Minkyu Son

State-of-the-art cuprous oxide (Cu2O) photocathodes for photoelectrochemical (PEC) water splitting have a long tradition of using gold (Au)-coated F-doped SnO2 (FTO) substrates for the improvement of Cu2O electrodeposition and overall PEC performance. Au i ...

Royal Soc Chemistry2017

Nickel-catalyzed Hydrosilylation of Alkenes and Transition-Metal-Free Intermolecular α-C-H Amination of Ethers

Ivan Buslov

Transition-metal-catalyzed hydrosilylation of olefins is one of the most important methods for the preparation of organosilicon compounds, which have broad applications in both synthetic and material chemistry. For decades, precious metals, principally pla ...

EPFL2016

Coupling of electrocatalysts to photoabsorbers for solar fuels production

Carlos Gilberto Morales Guio

The direct transformation of sunlight into fuels and chemicals has attracted considerable attention for the potential impact on the storage of solar energies at large scales and the reduction of CO2 emissions. More than 80% of our current global energy con ...

EPFL2016

Enhancing the Electrochemical and Electronic Performance of CVD-Grown Graphene by Minimizing Trace Metal Impurities

Klaus Kern, Kannan Balasubramanian

The presence of unwanted impurities in graphene is known to have a significant impact on its physical and chemical properties. Similar to carbon nanotubes, any trace metals present in graphene will affect the electrocatalytic properties of the material. He ...

Wiley-V C H Verlag Gmbh2014

Amorphous molybdenum sulfides as hydrogen evolution catalysts

Xile Hu, Carlos Gilberto Morales Guio

Providing energy for a population projected to reach 9 billion people within the middle of this century is one of the most pressing societal issues. Burning fossil fuels at a rate and scale that satisfy our near-term demand will irreversibly damage the liv ...

American Chemical Society2014

Composite material comprising a precious metal, manufacturing process and use of such a material

Andreas Mortensen, Ludger Weber, Reza Tavangar Hamzehkolaei

Composite material combining: - a precious metal or an alloy containing a precious metal, - and a boron-based ceramic having a melting point above that of said precious metal and a density at most equal to 4 g/cm3. ...

2012

Determination of trace metals accumulated and internalized by marine phytoplankton; interferences with colloidal organic matter

Vera Slaveykova-Startcheva

In the present work, we study the effects that aggregation of humic acids in seawater, and its adsorption to surfaces, can have on the determination of Cu and Pb accumulation by phytoplankton within the context of metal bioavailability studies, using the d ...

Taylor & Francis Ltd2012

Al2O3 particle rounding in molten copper and Cu8wt%Al

Andreas Mortensen

We investigate processing-microstructure relationships in the production of Al2O3 particle reinforced copper composites by solidification processing. We show that during production of the composites by gas-pressure infiltration of packed Al2O3 particle pre ...

Springer US2012

Large Micromirror Array Based on a Scalable Technology for Astronomical Instrumentation

Michael David Canonica

Understanding the formation of galaxies and studying the expansion of the Universe, need the spectral characterization of faint astronomical objects such as stars or galaxies. From these spectra, the distance, the velocity and the chemical composition of t ...

EPFL2012