Publications associées à Energy-selective neutron imaging for morphological and phase analysis of iron-nickel meteorites

How Reproducible is the Synthesis of Zr-Porphyrin Metal-Organic Frameworks? An Interlaboratory Study

Jocelyn Richard Roth, Wendy Lee Queen, Rawan Al Natour

Metal-organic frameworks (MOFs) are a rapidly growing class of materials that offer great promise in various applications. However, the synthesis remains challenging: for example, a range of crystal structures can often be accessed from the same building b ...

Wiley-V C H Verlag Gmbh2024

Photo-Fenton inactivation of MS2 bacteriophage at alkaline pH by Fe salts or nm to μm-sized oxides, and the Janus-faced effects of natural organic matter in surface waters

César Pulgarin, Stefanos Giannakis, Ogadimma Cassandra Oji-Okoro, Giulio Farinelli

In this study, MS2 bacteriophage was inactivated by homogeneous and heterogeneous photo-Fenton processes in an alkaline matrix (pH 8) using low concentrations of H2O2 and iron forms (1 mg/L), including Fe(II), Fe(III), and Fe (hydr)oxides. As a reference, ...

Elsevier2024

High brightness neutron source optimized for very high pulsed magnetic field experiments

Mina Akhyani

Conducting neutron scattering experiments in the presence of high pulsed magnetic fields, namely above 40 T, provides valuable information about the magnetic structures of materials. However, these experiments are challenging and time-consuming because the ...

EPFL2024

Anomalous Hall effect and magnetic structure of the topological semimetal (Mn0.78Fe0.22)3Ge

Jan Persson, Jian Rui Soh

Me3+8Ge, being a Weyl semimetal, shows a large anomalous Hall effect (AHE), which decreases slowly with an increase in 8 from 0.1 to 0.4. However, AHE in this compound remains significantly large in the whole range of 8 because of the robust nature of the ...

AMER PHYSICAL SOC2023

Blue ice in Antarctica: The gateway to travel in time and space

Devis Tuia, Benjamin Alexander Kellenberger, Marc Conrad Russwurm, Veronica Tollenaar

Antarctica has unique areas that expose blue ice, which contrast to most of the continent (~98%) that is covered by snow. Some of these blue ice areas (BIAs) contain meteorite concentrations and (very) old ice, making them very valuable for understanding o ...

GFZ German Research Centre for Geosciences2023

Magnetic structure of the two-dimensional XY antiferromagnet Sr2CoSi2O7 studied using single-crystal neutron diffraction

Bálint Náfrádi

We report a combined polarized and unpolarized neutron diffraction study on a multiferroic Sr2CoSi2O7 (SCSO) single crystal below and above the antiferromagnetic ordering temperature TN = 6.5 K. Unpolarized neutron diffraction measurements at 15 K confirm ...

AMER PHYSICAL SOC2023

Epidemic Learning: Boosting Decentralized Learning with Randomized Communication

Rachid Guerraoui, Anne-Marie Kermarrec, Sadegh Farhadkhani, Rafael Pereira Pires, Rishi Sharma, Marinus Abraham de Vos

We present Epidemic Learning ( EL ), a simple yet powerful decentralized learning (DL) algorithm that leverages changing communication topologies to achieve faster model convergence compared to conventional DL approaches. At each round of EL, each node sen ...

2023

Hot rocks: Constraining the thermal conditions of the Mistastin Lake impact melt deposits using zircon grain microstructures

Cyril Cayron

The production of superheated melt during hypervelocity impact events has been proposed to be a common occurrence on terrestrial planetary bodies. Recent direct evidence of superheated impact melt temperatures exceeding > 2370 degrees C from the Kamestasti ...

ELSEVIER2022

An elementary treatment on the diffraction of crystalline structures

Gervais Chapuis

Although W. L. Bragg's law can be easily derived for beginners in the field of crystallography, its interpretation however seems to cause some difficulties which lies essentially in the relation between the concept of lattice planes and the unit cell const ...

2022

Bragg edge tomography characterization of additively manufactured 316L steel

Christian Leinenbach, Roland Logé, Nikola Kalentics, Efthymios Polatidis, Markus Strobl

In this work we perform a neutron Bragg edge tomography of stainless steel 316L additive manufacturing samples, one as built via standard laser powder bed fusion, and one using the novel three-dimensional (3D) laser shock peening technique. First, we consi ...

AMER PHYSICAL SOC2022

Quantifying the Solution Structure of Metal Nanoclusters Using Small-Angle Neutron Scattering

Francesco Stellacci, Stefan Guldin, Zhi Luo, Ye Yang, Huayan Yang

Metal nanoclusters are a unique class of synthetic material, as their crystal structures can be resolved using X-ray diffraction, and their chemical formula can be precisely determinated from mass spectroscopy. However, a complete structure characterizatio ...

Wiley-VCH Verlag GmbH2022

New methods for structure determination and speciation by NMR crystallography

Martins Balodis

NMR crystallography has been around for half a century, but with the advent of NMR crystal structure determination protocols in the last decade it has shown perspectives that were not seen before. Amalgamation of NMR and crystal structure determination has ...

EPFL2022

Concrete cancer : characterization of Alkali Silica Reaction early stage products by electron microscopy

Solène Anne-Lise Albinski

Concrete deterioration is a natural process, which has to be carefully monitored over a the service life of a structure. The Alkali-Silica Reaction (ASR) is a slow-process degradation, which devel-ops over decades and is therefore difficult to predict. Sin ...

EPFL2022

Structure-property relationships and mixed conductivity in layered hybrid perovskites based on phenyl-derived spacers

Algirdas Ducinskas

Hybrid halide perovskites are currently one of the most studied semiconductors. However, due to poor intrinsic and extrinsic stability, further developments to commercialize devices based on hybrid halide perovskites are limited. Many different strategies ...

EPFL2022

Effect of Co-Substitution on Hydrogen Absorption and Desorption Reactions of YMgNi4-Based Alloys

Loris Giovanni Lombardo, Andreas Züttel, Wen Luo, Heena Yang

YMgNi4-based alloys exhibit reversible hydrogen absorption and desorption reactions at near room temperature. Here, we report that Co-substituted YMgNi4-based alloys exhibited higher hydrogen contents and lower hydrogen absorption and desorption reaction p ...

AMER CHEMICAL SOC2022

Aggregate dissolution in different pore solutions

Mahsa Bagheri

The occurrence of cracking due to alkali silica reaction (ASR) affects the service life of concrete structures. The dissolution of silica-containing minerals within aggregates causes the formation of ASR products, which fill macroscopic cracks and cause th ...

EPFL2021

Static and dynamic properties of non-collinear quantum antiferromagnets explored by neutron scattering

Luc Testa

This thesis is devoted to the investigation of static and dynamic properties of two different sets of quantum magnets with neutron scattering techniques and the help of linear spin wave theory. Both systems are copper-based with spin-1/2, which makes them ...

EPFL2021

Direct Visualization of Atomic-Scale Heterogeneous Structure Dynamics in MnO2 Nanowires

Xin Peng, Kangning Zhao, Yuyang Zhang

Manganese oxides are attracting great interest owing to their rich polymorphism and multiple valent states, which give rise to a wide range of applications in catalysis, capacitors, ion batteries, and so forth. Most of their functionalities are connected t ...

AMER CHEMICAL SOC2021

Order and dynamics in Kagome like compound Cu2OSO4 and other quantum magnets

Virgile Yves Favre

This thesis presents results of studies of novel compounds modeling complex fundamental physics phenomena. Cu2OSO4 is a copper based magnetic Mott Insulator system, where spin half magnetic moments form a new type of lattice. These intrinsically quantum pi ...

EPFL2021

Development of microdevices for the in-plane thermoelectric characterization of deposited films

Stefano Mischler

Measuring the thermoelectric transport properties of a material is a prerequisite to determining its usefulness for application in waste heat recovery or cooling and the basis for devising improvement strategies. While well-established characterization met ...

ELSEVIER2021