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Showing 1 to 14 of 14 for “"MC-ICP-MS"”.
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Uranium isotopic fractionation induced by U(VI) adsorption onto common aquifer minerals
… dissolved U(VI) was analyzed by a double-spike MC-ICP-MS method. Adsorption to the studied solid phases induces an average isotopic fractionation of -0.17‰ with the adsorbed U(VI) isotopically lighter. U(VI) speciation can affect the magnitude of isotopic fractionation with uranyl carbonato and …
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Isotopic study of uranium: determining the isotopic fractionation of uranium during abiotic reduction with iron(II)
… were conducted with samples analyzed by a MC-ICP-MS. We find aqueous Fe(II) has a limited ability to reduce U(VI) and no isotopic data is reported. Stoichiometric magnetite (χ=0.49) reduces U(VI) to U(VI) completely and rapidly as confirmed by XANES analysis, but induces no shift in …
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Source Constraints of Ore Metals in Mississippi Valley-type Deposits in Central and Eastern Tennessee using Pb Isotopes
… and may have different Pb sources. Nu Plasma MC-ICP-MS Pb isotopic analyses on sulfides from Central and East TN were conducted and the metal sources evaluated. Results were plotted on covariation diagrams with respect to the average crustal growth curve from Stacy and Kramers (1975) and the …
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The marine biogeochemistry of chromium isotopes
… matrixes. Isotope analysis is performed on a MC-ICP-MS IsoProbe. The addition of a 50Cr-54Cr double spike allows for accurate correction of procedural and instrumental Cr mass fractionations. The first Cr isotope ratio data for a full water column profile in the Pacific Ocean is presented. …
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The Development of Chemical and Biological Profiling for the Forensic Provenancing of Norfolk Soils
… be created using geographical information systems to house multiple datasets and be used to map soils across geographical areas. Generally, the more variables available with which to compare items, the greater the certainty a forensic analyst can have when asserting their similarity; this …
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Antimony isotopes as indicators of redox reactions in aqueous systems: fractionation during Sb(V) reduction by sulfide and isotope exchange kinetics between dissolved Sb(III) and Sb(V)
… use anion exchange resin and hydride generation MC-ICP-MS methods to obtain precise measurements of 123Sb/121Sb. The anion exchange method is also effective for separating Sb(III) from Sb(V). First, we find that isotopic exchange between aqueous Sb(V) and Sb(III) at higher than natural …
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Lead isotopes as a palaeodietary tracer in southwestern South Africa
… of Sr is limited at near-coastal areas, which forms a major part of this study area. This is because Sr has a relatively high concentration and long residence time in seawater. In addition, coastal soils contain not only aerosol-derived marine Sr, but frequently also include fragments of shells …
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The marine biogeochemistry of chromium isotopes
… matrixes. Isotope analysis is performed on a MC-ICP-MS IsoProbe. The addition of a 50Cr-54Cr double spike allows for accurate correction of procedural and instrumental Cr mass fractionations. The first Cr isotope ratio data for a full water column profile in the Pacific Ocean is presented. …
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Spatially controlled Fe isotope variations at Torres Del Paine
… of a convergent margin related pluton aims to understand the nature of granite and silicic igneous rock formation. Samples were collected along four well defined spatial transects, focusing on major plutonic contacts between the country rock, granite and mafic units. Results collected by …
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Implementing a new method to measure δ³⁴SSO₄ in ice cores to assess sulfate sources in West Antarctica
… about the interconnection of climate systems and past climate events. The major sulfate sources in Antarctica are sea salt, biogenic activity, and volcanic activity, though volcanic events have a limited ~1–2 year deposition period. Each source can be identified by its unique sulfur …
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Iron Isotope Cosmochemistry
… mass-dependent Fe isotope fractionation mechanisms are also discussed. At last, I review the technique of high precision isotopic analyses of iron using anion-exchange chromatography and MC-ICP-MS.</p><p>In Chapter 2, I focus on the non-mass-dependent fractionation of Fe isotopes and examine the …
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Desarrollo y aplicación de metodologías de medida de relaciones isotópicas en muestras sólidas mediante ablación láser acoplada a espectrometría de masas
… sólidas mediante ablación láser acoplado a ICP-MS y su aplicación a la resolución de distintos problemas analíticos dentro del campo de los estudios de trazabilidad. A lo largo de este trabajo se consideraron tanto sistemas naturales, donde la medida de relaciones isotópicas fue utilizable …
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Silicate weathering in the Himalayas: Constraints from the Li isotopic composition of river systems
Chemical weathering of silicate rock consumes atmospheric CO2 and supplies the oceans with cations, thereby controlling both seawater chemistry and climate. The rate of CO2 consumption is closely linked to the rate of CO2 outgassing from the planetary interior, providing a negative feedback loop …