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Benchmarking the simulation of Cr isotope fractionation
Computational Geosciences, 2014A benchmark problem set consisting of four problem levels was developed for the simulation of Cr isotope fractionation in 1D and 2D domains. The benchmark is based on a recent field study where Cr(VI) reduction and accompanying Cr isotope fractionation occurs abiotically by an aqueous reaction with dissolved Fe 2+ (Wanner et al., 2012., Appl. Geochem.,
Wanner, Christoph +4 more
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Analytical and Bioanalytical Chemistry, 2006
A method is presented for the simultaneous determination of Cr(III) and Cr(VI) in yeast using species-specific double-spike isotope dilution (SSDSID) with anion-exchange liquid chromatography (LC) separation and sector field inductively coupled plasma mass spectrometric (SF-ICP-MS) detection. Total Cr is quantitated using ID SF-ICP-MS.
Yang, L. +3 more
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A method is presented for the simultaneous determination of Cr(III) and Cr(VI) in yeast using species-specific double-spike isotope dilution (SSDSID) with anion-exchange liquid chromatography (LC) separation and sector field inductively coupled plasma mass spectrometric (SF-ICP-MS) detection. Total Cr is quantitated using ID SF-ICP-MS.
Yang, L. +3 more
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Cr isotope systematics in the Connecticut River estuary
Chemical Geology, 2019Abstract Stable chromium (Cr) isotopes (expressed in δ53Cr as the deviation of 53Cr/52Cr in samples from the international standard NIST SRM 979) are an emerging paleoredox proxy that has been used to track Earth's redox evolution over a range of timescales.
Zeyang Sun, Xiangli Wang, Noah Planavsky
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Oxygen isotope compositions of chondrules in CR chondrites
Geochimica et Cosmochimica Acta, 2006Abstract We report in situ ion microprobe analyses of oxygen isotopic compositions of olivine, low-Ca pyroxene, high-Ca pyroxene, anorthitic plagioclase, glassy mesostasis, and spinel in five aluminum-rich chondrules and nine ferromagnesian chondrules from the CR carbonaceous chondrites EET92042, GRA95229, and MAC87320.
Alexander N. Krot +2 more
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Hydrogen isotopic composition of the water in CR chondrites
Geochimica et Cosmochimica Acta, 2013Abstract The thermal and aqueous alteration experienced by QUE 99177, MET 00426, EET 92042, GRA 95229, Renazzo and Al Rais CR chondrites was assessed through multi-technique characterization of their the carbonaceous matter and hydrated mineral phases.
Bonal, L. +5 more
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Speciated isotope dilution analysis of Cr(III) and Cr(VI) in water by ICP-DRC-MS
Talanta, 2008An isotope dilution method has been developed for the speciation analysis of chromium in natural waters which accounts for species interconversions without the requirement of a separation instrument connected to the mass spectrometer. The method involves (i) in-situ spiking of the sample with isotopically enriched chromium species; (ii) separation of ...
H-L, Ma, P A, Tanner
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, 2020
Chromium (Cr) is a redox-sensitive metal element with two natural oxidation states, commonly as the soluble Cr (VI) oxyanion (CrO42− or HCrO4−) and the insoluble Cr (III)-compounds.
Wei Wei +4 more
semanticscholar +1 more source
Chromium (Cr) is a redox-sensitive metal element with two natural oxidation states, commonly as the soluble Cr (VI) oxyanion (CrO42− or HCrO4−) and the insoluble Cr (III)-compounds.
Wei Wei +4 more
semanticscholar +1 more source
Isotopic fractionation and reaction kinetics between Cr(III) and Cr(VI) in aqueous media
Geochimica et Cosmochimica Acta, 2010Abstract The redox-sensitive stable isotope geochemistry of chromium bears the potential to monitor the attenuation of chromate pollution and to investigate changes in environmental conditions in the present and the past. The use of stable Cr isotope data as a geo-environmental tracer, however, necessitates an understanding of the reaction kinetics ...
Zink, Sonja +2 more
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Cr-isotopes: analytical methods, spike calculations and application to Environmental Sciences
Acta Vulcanologica : journal of the national volcanic group of Italy, 2007Chromium is found in soils and waters from natural sources and anthropogenic activities. It occurs in the environment in two main valence states; hexavalent Cr(VI) and trivalent Cr(III). Within the range of pH and redox potential commonly found in soils and water, there are two trivalent forms of Cr (the Cr3+ cation and the CrO2- anion) and two ...
PETRINI, RICCARDO +2 more
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The Cr-isotope signature of surface seawater — A global perspective
Chemical Geology, 2016Abstract This study presents chromium-isotope data (expressed as δ 53 Cr) and chromium concentrations (Cr) of surface seawater (0–2 m depth) from a variety of locations worldwide. In addition to samples from the open ocean (Arctic, Southern, Pacific, and Atlantic Oceans), samples were analysed from areas with more restricted water exchange rates (the
Cora Paulukat +3 more
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