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Showing 1 to 7 of 7 for “"Uranium isotopes"”.
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Uranium isotopes as indicators of uranium immobilization and remobilization in contaminated aquifer settings
… adsorption can complicate data interpretation. U isotopes (238U/235U) provide a more direct indicator of these geochemical reactions controlling U mobility. U(VI) reduction induces a strong fractionation of U isotopes, shifting the U isotopes of the remaining U(VI) and producing U(IV) with a …
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Fission fragment mass distributions and total kinetic energy release of 235-uranium and 238-uranium in neutron-induced fission at intermediate and fast neutron energies LA-UR-15-28829
… and its variance $\sigma_{TKE}$ for both uranium isotopes that correlate to multi-chance fission in the cross section. A low $E_n$ turnover in the $\overline{TKE}$ was observed for $^{235}$U which had only been hinted at in previous experiments. Correlated $TKE$ and masses are also …
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Uranium isotopic fractionation induced by U(VI) adsorption onto common aquifer minerals
Uranium groundwater contamination due to mining and processing affects numerous sites in the western United States. Bioreduction of soluble, mobile U(VI) to U(IV)-bearing solids is a common remediation strategy. Uranium isotopes (238U/235U) have been utilized to track the progress of microbial …
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The effects of the major design and operation variables on the enrichment by thermal diffusion of aqueous sugar solutions
… scale for accomplishing the separation of isotopes, azeotropes, and hydrocarbons of a particular series. Although the thermal diffusion effect, wherein a gradient of temperature in a body of fluid gives rise to a gradient of concentration, was discovered in 1856, it did not become …
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The Speciation of Dissolved Uranium in Marine Waters
<p>Uranium has been used extensively for quantifying geochemical processes in the marine environment. Due to its low concentration, about 3.3 μg/1, some form of preconcentration is required for analysis. The two most widely used pre-concentration schemes are co-precipitation with iron hydroxide, …
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The isotope geochemistry of uranium: Igneous petrology, ore deposits, and groundwater contamination
… three geologic settings: basalt differentiation, uranium ore genesis, and the remediation of a uranium-contaminated groundwater system. In the latter two cases, 238U/235U is used as a tracer of uranium reduction. 238U preferentially enters the reduced (solid) U phase, thus analysis of U ores can …