The plutonium rapid response in vitro bioassay method described here was designed to determine
238
Pu,
239
Pu, and
240
Pu concentration in urine samples from workers with potential internal ...contamination. Results provide quick and actionable information about the level of contamination necessary to assist making further medical decisions, including chelation therapy. The radiochemical procedure can be performed within approximately 48 h, including sample preparation, measurement(s) by alpha spectrometry and/or inductively coupled plasma mass spectrometry (ICP-MS), and data evaluation.
In 2014 the United States Department of Energy and the China Institute of Atomic Energy collaborated in a study measuring the model ages of uranium certified reference materials. Lawrence Livermore ...National Laboratory (LLNL) and Los Alamos National Laboratory (LANL), and the Chinese Institute of Atomic Energy (CIAE) determined
230
Th–
234
U model ages for uranium certified reference materials U010 and U850. The aim of this work was to collaborate with CIAE and compare methods for measuring the age of bulk uranium materials using the
230
Th–
234
U radiochronometer. Accurate results for age-dating depend on the accurate calibration of the tracer materials (e.g.,
229
Th and
233
U) used for the isotope dilution mass spectrometry (IDMS) analyses. To facilitate inter-comparison of results, samples of a
230
Th standard reference material were distributed to each laboratory for
229
Th tracer inter-calibration. The resulting
230
Th–
234
U model ages from this collaboration for U010 ranged from March 1956 to January 1959, which agree with the known material production date of June 5th, 1958. The determined model ages for U850 were from December 1955 to October 1957, which agree with the material production date of December 31, 1957. All three laboratories used independent methods to determine model ages for uranium standards that agree with known production ages and with previously reported results.
This interlaboratory study measured thorium concentrations and isotope compositions in uranium ore concentrates from different geographical locations to examine whether thorium impurities may be ...useful forensic signatures for uranium ore concentrates found out of regulatory control. Measured
230
Th/
232
Th in fifteen uranium ore concentrates record over three orders of magnitude of compositional variation. Results demonstrate that
230
Th/
232
Th used in combination with U/Th ratios resulted in a unique signature for individual uranium ore concentrates from different processing locations. Data presented here suggest potential for
230
Th/
232
Th and U/Th to be used as comparative signatures to investigate the provenance of seized uranium ore concentrates.
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