Publications associées à A von Hamos spectrometer for in situ sulfur speciation by non-resonant sulfur K alpha emission spectroscopy

Reproductive isolation arises during laboratory adaptation to a novel hot environment

Background: Reproductive isolation can result from adaptive processes (e.g., ecological speciation and mutation-order speciation) or stochastic processes such as "system drift" model. Ecological speciation predicts barriers to gene flow between populations ...

BMC2024

Poisoning Effects of Cerium Oxide (CeO2) on the Performance of Proton Exchange Membrane Fuel Cells (PEMFCs)

Jan Van Herle, Hossein Pourrahmani

In this study, the poisoning effects of cerium oxide (CeO2) as the contaminant on the performance of proton exchange membrane fuel cells (PEMFCs) are evaluated. An experimental setup was developed to analyze the performance characteristic (I-V) curves in c ...

MDPI2022

Fe-57-Enrichment effect on the composition and performance of Fe-based O-2-reduction electrocatalysts

Jeremy Luterbacher, Benjamin Pierre Le Monnier

Pt-group metal (PGM)-free catalysts of the Me-N-C type based on abundant and inexpensive elements have gained importance in the field of oxygen reduction reaction (ORR) electrocatalysis due to their promising ORR-activities. Their insufficient stability, h ...

2021

A novel hydrogenic spectroscopic technique for inferring the role of plasma-molecule interaction on power and particle balance during detached conditions

Basil Duval, Kevin Henricus Annemarie Verhaegh, Mirko Wensing, Artur Perek

Detachment, an important mechanism for reducing target heat deposition, is achieved through reductions in power, particle and momentum; which are induced through plasma-atom and plasma-molecule interactions. Experimental research in how those reactions pre ...

IOP PUBLISHING LTD2021

Constraining the response factors of an extractive electrospray ionization mass spectrometer for near-molecular aerosol speciation

Yandong Tong, Julia Schmale, Imad El Haddad

Online characterization of aerosol composition at the near-molecular level is key to understanding chemical reaction mechanisms, kinetics, and sources under various atmospheric conditions. The recently developed extractive electrospray ionization time-of-f ...

2021

White-line evolution in shocked solid Ta evidenced by synchrotron x-ray absorption spectroscopy

Richard Gaal

Time-resolved x-ray absorption experiments have been performed on shocked tantalum. Using a single 100 ps synchrotron x-ray pulse, nanosecond-lived equilibrium states of shocked solid Ta have been measured by L-3-edge absorption spectroscopy. The energy sh ...

2020

Ultrafast X-ray Spectroscopy of Heme Proteins

Dominik Kinschel

With the advent of X-ray free-electron lasers (XFELs) time-resolved X-ray spectroscopic techniques have advanced to the femtosecond regime. These are element selective techniques which offer unique insight into the electronic and chemical environment and d ...

EPFL2020

Evaluation of materials for iodine and technetium immobilization through sorption and redox-driven processes

Daniel Teav Sun, Wendy Lee Queen

Radioactive iodine-129 (I-129) and technetium-99 (Tc-9(9)) pose a risk to groundwater due to their long half-lives, toxicity, and high environmental mobility. Based on literature reviewed in Moore et al. (2019) and Pearce et aL (2019), natural and engineer ...

ELSEVIER2020

Oxygen evolution reaction catalyzed by first-row transition metal oxides: stability and mechanism

Aliki Moysiadou

Water splitting offers the opportunity for storing solar energy and, thus, producing carbon-neutral and renewable solar fuels. The process, known as artificial photosynthesis, is limited by the electrocatalytic conversion of water into molecular oxygen. El ...

EPFL2020

Determination of isotope ratio in the divertor of JET-ILW by high-resolution H alpha spectroscopy: H-D experiment and implications for D-T experiment

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

The data of the H alpha high-resolution spectroscopy, collected on the multiple lines of sight, which cover the entire divertor space in poloidal cross-section, during the recent hydrogen-deuterium experiments in JET-ILW (ITER-like wall), are processed. A ...

IOP Publishing Ltd2019

Diagnostic of fast-ion energy spectra and densities in magnetized plasmas

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

The measurement of the energy spectra and densities of alpha-particles and other fast ions are part of the ITER measurement requirements, highlighting the importance of energy-resolved energetic-particle measurements for the mission of ITER. However, it ha ...

IOP PUBLISHING LTD2019

Observation of the 1S-2P Lyman-alpha transition in antihydrogen

Shirit Cohen

In 1906, Theodore Lyman discovered his eponymous series of transitions in the extreme-ultraviolet region of the atomic hydrogen spectrum(1,2). The patterns in the hydrogen spectrum helped to establish the emerging theory of quantum mechanics, which we now ...

Nature Publishing Group2018

Incremental Kinetic Modeling of Spectroscopic Data using a Reduced Calibration Model

Dominique Bonvin, Julien Léo Billeter

The identification of kinetic models is an important step for the monitoring, control and optimization of chemical processes. Kinetic models are often based on first principles that describe the evolution of concentrations by means of conservation and cons ...

2017

Excited state X-ray absorption spectroscopy: Probing both electronic and structural dynamics

Majed Chergui, Simon Neville

We investigate the sensitivity of X-ray absorption spectra, simulated using a general method, to properties of molecular excited states. Recently, Averbukh and co-workers [M. Ruberti et al., J. Chem. Phys. 140, 184107 (2014)] introduced an efficient and ac ...

American Institute of Physics2016

A universal chemical potential for sulfur vapours

Davide Tiana

The unusual chemistry of sulfur is illustrated by the tendency for catenation. Sulfur forms a range of open and closed S-n species in the gas phase, which has led to speculation on the composition of sulfur vapours as a function of temperature and pressure ...

2016

Role of sulfur in BaVS3 probed by S K-edge absorption spectroscopy

Helmuth Berger, László Forró

We show that the quasi-1D behavior of BaVS3 can be understood analyzing the X-ray absorption near edge spectra at the sulfur K edge. Linear dichroism experiments, analyzed with the help of ab initio calculations, reveal two strong and polarization dependen ...

Elsevier Science Bv2015

Identifying the major intermediate species by combining time-resolved X-ray solution scattering and X-ray absorption spectroscopy

Thomas James Penfold

Identifying the intermediate species along a reaction pathway is a first step towards a complete understanding of the reaction mechanism, but often this task is not trivial. There has been a strong on-going debate: which of the three intermediates, the CHI ...

Royal Soc Chemistry2015

Physical properties and evolutionary state of the Lyman alpha emitting starburst galaxy IRAS 08339+6517

Hakim Atek

Context. Though Ly alpha emission is one of the most used tracers of massive star formation at high redshift, it is strongly affected by neutral gas radiation transfer effects. A correct understanding of these effects is required to properly quantify the s ...

EDP Sciences2014

Optofluidic-tunable color filters and spectroscopy based on liquid-crystal microflows

Julien Cuennet, Demetri Psaltis, Andreas Vasdekis

The integration of color filters with microfluidics has attracted substantial attention in recent years, for on-chip absorption, fluorescence, or Raman analysis. We describe such tunable filters based on the micro-flow of liquid crystals. The filter operat ...

Royal Society of Chemistry2013

Dielectric properties of silver nanoparticles coated with silica shells of different thicknesses

Heinrich Hofmann, Jose Enrico Quijano Quinsaat

Core/shell nanoparticles having metallic silver nanoparticle cores of similar to 38 nm in diameter and silica shells of different thicknesses ranging from similar to 3.6-20 nm were prepared. For the silica coating, a slightly modified Stober method was use ...

RSC Publishing2013