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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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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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Japan gets new U for enrichment as global power and fuel plans grow
President Trump is in Japan today, with a visit with new Prime Minister Sanae Takaichi on the agenda. Takaichi, who took office just last week as Japan’s first female prime minister, has already spoken in favor of nuclear energy and of accelerating the restart of Japan’s long-shuttered power reactors, as Reuters and others have reported. Much of the uranium to power those reactors will be enriched at Japan’s lone enrichment facility—part of Japan Nuclear Fuel Ltd.’s Rokkasho fuel complex—which accepted its first delivery of fresh uranium hexafluoride (UF₆) in 11 years earlier this month.
W. N. McElroy, S. Berg, G. Gigas
Nuclear Science and Engineering | Volume 27 | Number 3 | March 1967 | Pages 533-541
Technical Paper | doi.org/10.13182/NSE86-A17618
Articles are hosted by Taylor and Francis Online.
An iterative unfolding method has been applied to several types of neutron environment to obtain neutron-flux spectra. The mathematical procedure involves selection of an initial spectral approximation and its subsequent perturbation to obtain a best-fit simultaneous solution for a system of ten or more activation integral equations. The present analytical studies support earlier results that integral neutron flux may be obtained from foil data with accuracies to within ± 10 to 30% at any point over the energy range from 4 × 10−7 to 18 MeV, if the activation cross-section data and measured activation rates are accurate to ± 10%.