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DOE OSTI · 2563199

Chemical speciation correlated with microstructural heterogeneity of interdicted uranium materials

Pacold, Joseph I. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000246975896)·Smiles, Danil E. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)]·Mara, Michael W. [University of California, Berkeley, CA (United States)] (ORCID:0000000337669368)·Ward, Jesse D. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:0000000253464971)·Shuh, David K. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000231043260)·Tyliszczak, Tolek [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0009000994277062)·Kristo, Michael. J. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000169956308)·Keegan, Elizabeth [Australian Nuclear Science and Technology Organisation (ANSTO), NSW (Australia)]
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Abstract

Two uranium powders seized by law enforcement in Victoria, Australia, have been characterized by established nuclear forensic methods in a previously published study. Here, in this work, the results of further characterization by a scanning transmission x-ray microscope (STXM) operating in the soft x-ray regime are reported. STXM images are used to estimate the elemental distribution in micrometer-scale particles of each powder, and oxygen K-edge absorption spectra are used to determine the chemical state of uranium. The results of the current study are consistent with the previous analysis; the first powder is found to be a potassium-uranium hydrate, while the second powder is determined to be a mixture of uranium oxides primarily consisting of UO 3 .

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38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRYSTXMchemical elementschemical speciationenvironmental studiesforensic scienceimage processingnuclear forensicsnuclear fuelsoft x-ray synchrotron radiationuraniumuranium oxidex-ray absorption spectroscopyx-ray microscopy

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Pacold, Joseph I. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000246975896), Smiles, Danil E. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)], Mara, Michael W. [University of California, Berkeley, CA (United States)] (ORCID:0000000337669368), Ward, Jesse D. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:0000000253464971), Shuh, David K. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000231043260), Tyliszczak, Tolek [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0009000994277062), Kristo, Michael. J. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000169956308), Keegan, Elizabeth [Australian Nuclear Science and Technology Organisation (ANSTO), NSW (Australia)]. 2025-04-24. Chemical speciation correlated with microstructural heterogeneity of interdicted uranium materials. https://doi.org/10.1116/6.0004526

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