Publications by authors named "Allison Wende"

Chelonians (turtles, tortoises, and sea turtles) grow scute keratin in sequential layers over time. Once formed, scute keratin acts as an inert reservoir of environmental information. For chelonians inhabiting areas with legacy or modern nuclear activities, their scute has the potential to act as a time-stamped record of radionuclide contamination in the environment.

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Unlabelled: The isolation and purification of protactinium from uranium materials is essential for Pa-U radiochronometry, but separating Pa from uranium-niobium alloys, a common material in the nuclear fuel cycle, is challenging due to the chemical similarity of Pa and Nb. Here we present three resin chromatography separation techniques for isolating Pa from U and Nb which were independently developed by three different laboratories through ad hoc adaptations of standard operating procedures. Our results underscore the need for and value of purification methods suitable for a diversity of uranium-based materials to ensure the operational readiness of nuclear forensics laboratories.

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Article Synopsis
  • The study compares radio-chronometric ages of four plutonium-certified reference materials with differing chemical forms and isotopic compositions to evaluate current age dating techniques for nuclear materials.
  • Modern analytical methods, including various mass spectrometers, were employed across different laboratories, highlighting variations in age determination precision and the need for standardized isotopic references.
  • Results suggest that while trace level analytical labs may have slightly higher uncertainties compared to bulk sample labs, both can achieve similar model purification ages using established isotope measurement techniques.
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This paper describes an approach to measuring extinct fission products that would allow for the characterization of a nuclear test at any time. The isotopic composition of molybdenum in five samples of glassy debris from the 1945 Trinity nuclear test has been measured. Nonnatural molybdenum isotopic compositions were observed, reflecting an input from the decay of the short-lived fission products (95)Zr and (97)Zr.

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