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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Inkjet droplets of radioactive material enable quick, precise testing at NIST
Researchers at the National Institute of Standards and Technology have developed a technique called cryogenic decay energy spectrometry capable of detecting single radioactive decay events from tiny material samples and simultaneously identifying the atoms involved. In time, the technology could replace characterization tasks that have taken months and could support rapid, accurate radiopharmaceutical development and used nuclear fuel recycling, according to an article published on July 8 by NIST.
G. C. Pomraning
Nuclear Science and Engineering | Volume 85 | Number 2 | October 1983 | Pages 188-191
Technical Note | doi.org/10.13182/NSE83-A27426
Articles are hosted by Taylor and Francis Online.
First-order perturbation formulas are derived that give the change in the eigenvalue of a reactive system due to a perturbation in the exterior shape of the system. In physical terms, this perturbation involves adding a thin layer of arbitrary material to the surface of the unperturbed system (or deleting material past a material discontinuity). From a mathematical viewpoint, the perturbation is sufficiently general to give rise to a nonanalytic behavior of the eigenvalue on the smallness parameter. Both transport theory and the diffusion approximation are treated.