Redox state during core formation on asteroid 4-Vesta
Graph Chatbot
Chattez avec Graph Search
Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.
AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.
The origin of micrometeorites (MMs) from asteroids and comets is well-established, but the relative contribution from these two classes remains poorly resolved. Likewise, determining the precise origin of individual MMs is an open challenge. Here, cosmic-r ...
Hexavalent uranium (U(VI)) is reduced to tetravalent uranium (U(IV)) by microorganisms (e.g., Geobacter or Shewanella spp.) as well as by abiotic reductants such as sulfide or Fe(II) species. During reduction, the heavy isotope (238U) is typically enriched ...
The thicknesss of the brittle lithosphere—the outer portion of a planetary body that fails via fracturing— plays a key role in the geological processes of that body. The properties of both a planet and its host star can influence that thickness, and the po ...
Stable isotope ratios of water (𝛿 18O,𝛿 2H) have long been used to study a core question in plant ecology and ecohydrology: “From where do plants take up water?” Indeed, decades of research has involved sampling potential plant water sources in the subsurf ...
Uranium isotopic signatures can be harnessed to monitor the reductive remediation of subsurface contamination or to reconstruct paleo-redox environments. However, the mechanistic underpinnings of the isotope fractionation associated with U reduction remain ...
In recent years, evidence has emerged that solid water can contain substantial amounts of guest species, such as small gas molecules-in gas hydrate structures-or ions-in salty ice structures-and that these 'filled' ice structures can be stable under pressu ...
ROYAL SOC2019
, , , ,
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
To date, the vast majority of studies seeking to link discharge to solute concentrations have been based on representations of fluid age distributions in watersheds that are time-invariant. As increasingly detailed spatial and temporal datasets become avai ...
New Haven2023
, ,
The stable isotopes of hydrogen and oxygen (delta H-2 and delta O-18, respectively) have been widely used to investigate tree water source partitioning. These tracers have shed new light on patterns of tree water use in time and space. However, there are s ...
WILEY2020
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 ...
