New reference materials for trace-levels of actinide elements in plutonium

Essex, Richard M.; Tandon, Lav; Gaffney, Amy; Hexel, Cole R.; Bostick, Debbie A.; Colletti, Lisa M.; Decker, Diana L.; Finstad, Casey C.; Giaquinto, Joe M.; Lujan, Elmer; Partridge, John D.; Roach, Benjamin D.; Rolinson, John; Samperton, Kyle; Slemmons, Alice K.; Spencer, Khalil J.; Stanley, Floyd E.; Townsend, Lisa E.; Treinen, Kerri C.; Williams, Ross W.; Worley, Christopher G.; Xu, Ning

doi:10.1515/ract-2021-1095

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DOE OSTI · 1846538

New reference materials for trace-levels of actinide elements in plutonium

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Abstract

In this report two plutonium oxides were prepared as unique reference materials for measurement of actinide elements present as trace constituents. Each reference material unit is approximately 200 mg of PuO 2 powder in a quartz glass bottle. Characterized attributes of the oxides included mass fractions of plutonium, americium, neptunium, and uranium. Isotope-amount ratios were also determined for plutonium and uranium, but neptunium and americium were observed to be monoisotopic 237 Np and 241 Am. Measurements for characterization and verification of the attributes show that plutonium and trace actinides are homogeneous with the exception of limited heterogeneity for uranium, primarily observed for the 238 U isotope. Model purification ages calculated from measured americium and uranium attribute values are consistent with material histories and indicate that these impurities are predominantly due to the decay of plutonium isotopes.

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38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY americium neptunium nuclear forensics plutonium reference material uranium

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Essex, Richard M., Tandon, Lav, Gaffney, Amy, Hexel, Cole R., Bostick, Debbie A., Colletti, Lisa M., Decker, Diana L., Finstad, Casey C., Giaquinto, Joe M., Lujan, Elmer, Partridge, John D., Roach, Benjamin D., Rolinson, John, Samperton, Kyle, Slemmons, Alice K., Spencer, Khalil J., Stanley, Floyd E., Townsend, Lisa E., Treinen, Kerri C., Williams, Ross W., Worley, Christopher G., Xu, Ning. 2021-11-12. New reference materials for trace-levels of actinide elements in plutonium. https://doi.org/10.1515/ract-2021-1095

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