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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
DOE extends Centrus’s HALEU production contract by one year
Centrus Energy has announced that it has secured a contract extension from the Department of Energy to continue—for one year—its ongoing high-assay low-enriched uranium (HALEU) production at the American Centrifuge Plant in Piketon, Ohio, at an annual rate of 900 kilograms of HALEU UF6. According to Centrus, the extension is valued at about $110 million through June 30, 2026.
K. Ganguly, A. Sengupta
Nuclear Science and Engineering | Volume 74 | Number 1 | April 1980 | Pages 1-12
Technical Paper | doi.org/10.13182/NSE80-A18940
Articles are hosted by Taylor and Francis Online.
In this paper, transport theory methods have been used to obtain a modified form of the PN approximation. This modification involves use of the exact asymptotic roots instead of the PN roots, resulting in a corresponding change in the Marshak free surface boundary conditions. Various numerical examples of this transport theoretic PN approximation have been given.
