Publications associées à Kinetic fractionation

The isotopic signature of U(V) during bacterial reduction

Marinella Mazzanti, Rizlan Bernier-Latmani, Margaux Camille Andréa Molinas, Radmila Faizova, Ashley Richards Brown

The two-step electron transfer during bacterial reduction of UVI to UIV is typically accompanied by mass-independent fractionation of the 238U and 235U isotopes, whereby the heavy isotope accumulates in the reduced product. However, the role of the UV inte ...

2024

Mercury Isotope Fractionation during Dark Abiotic Reduction of Hg(II) by Dissolved, Surface-Bound, and Structural Fe(II)

Lorenz Schwab

Stable mercury (Hg) isotope ratios are an emerging tracer for biogeochemical transformations in environmental systems, but their application requires knowledge of isotopic enrichment factors for individual processes. We investigated Hg isotope fractionatio ...

Amer Chemical Soc2023

Hydrogen Peroxide Formation during Ozonation of Olefins and Phenol: Mechanistic Insights from Oxygen Isotope Signatures

Urs von Gunten, Joanna Maria Houska

Mitigation of undesired byproducts from ozonation of dissolved organic matter (DOM) such as aldehydes and ketones is currently hampered by limited knowledge of their precursors and formation pathways. Here, the stable oxygen isotope composition of H2O2 for ...

AMER CHEMICAL SOC2023

Snow-Atmosphere Humidity Exchange at the Ice Sheet Surface Alters Annual Mean Climate Signals in Ice Core Records

Sonja Wahl

Surface processes alter the water stable isotope signal of the surface snow after deposition. However, it remains an open question to which extent surface post-depositional processes should be considered when inferring past climate information from ice cor ...

Amer Geophysical Union2023

High-useful yield and new autoionizing state of resonantly ionized tungsten

Reto Georg Trappitsch

In order to measure tungsten isotopic composition in presolar stardust grains that contain a limited number of atoms, we developed a new three-photon three-color resonance ionization scheme using titanium:sapphire lasers and the Laser Ionization of Neutral ...

ROYAL SOC CHEMISTRY2022

Toward waste valorization by converting bioethanol production residues into nanoparticles and nanocomposite films

Xun Liao, Muhammad Farooq

A "waste-valorization" approach was developed to transform recalcitrant hydrolysis lignin (HL) from secondgeneration bioethanol production into multifunctional bio-based products. The hydrolysis lignin (HL) was extracted with aqueous acetone, yielding two ...

ELSEVIER2021

Technical note: Evaluation of a low-cost evaporation protection method for portable water samplers

Jana Freiin von Freyberg

Automated field sampling of streamwater or precipitation for subsequent analysis of stable water isotopes (H-2 and O-18) is often conducted with off-the-shelf automated samplers. However, when water samples are stored in the field for days and weeks in ope ...

2020

Quantum kinetic energy and isotope fractionation in aqueous ionic solutions

Michele Ceriotti, Lu Wang

At room temperature, the quantum contribution to the kinetic energy of a water molecule exceeds the classical contribution by an order of magnitude. The quantum kinetic energy (QKE) of a water molecule is modulated by its local chemical environment and lea ...

ROYAL SOC CHEMISTRY2020

Non-crystalline tetravalent uranium species in the subsurface: formation and stability

Luca Loreggian

Uranium (U) contamination of ground and surface waters poses an acute hazard on the ecosystem and human health. Since the discovery of microbial U(VI) reduction, U bioremediation has been explored as a promising and cost-effective method compared to tradit ...

EPFL2019

Control of the hydrogen:deuterium isotope mixture using pellets in JET

Olivier Sauter, Ambrogio Fasoli, Yiming Li, Basil Duval, Jonathan Graves, Duccio Testa, Patrick Blanchard, Federico Alberto Alfredo Felici, Henri Weisen, Alessandro Pau

Deuterium pellets are injected into an initially pure hydrogen H-mode plasma in order to control the hydrogen: deuterium (H:D) isotope mixture. The pellets are deposited in the outer 20% of the minor radius, similar to that expected in ITER, creating trans ...

IOP Publishing Ltd2019