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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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.
Yoshiaki Oka, Shigehiro An, Hiroyuki Hashikura, Shun-ichi Miyasaka, Kinji Koyama
Nuclear Science and Engineering | Volume 79 | Number 3 | November 1981 | Pages 308-315
Technical Note | doi.org/10.13182/NSE81-A19407
Articles are hosted by Taylor and Francis Online.
Neutron reaction rates were measured by activation foils and thermoluminescent detectors through 180-cm-thick sodium shields and also through the layers of a 6-cm-thick iron plate and the sodium shields. A tightly coupled source shield configuration was constructed with the fast neutron reactor YAYOI as a source. Analysis of the experiments was made by using the DOT 3.5 code with 13-group neutron cross sections from the ENDF/B-IV library. Bondarenko-type self-shielding factors were included. The source condition for the analysis was determined by an iteration method from the experimental result at the reactor-shield interface and the initial estimate that was obtained from the core criticality calculation. The calculated neutron distributions in the shields agree with the experiments within ∼25% for the penetration through 180-cm-thick sodium. The shapes of the spatial distributions of the reaction rates in the shields show rather good agreement with the experiment.