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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.
L. Bridwell, Shawn Bucy
Nuclear Science and Engineering | Volume 37 | Number 2 | August 1969 | Pages 224-227
Technical Paper | doi.org/10.13182/NSE69-A20681
Articles are hosted by Taylor and Francis Online.
A mathematical model for the calculation of kinetic-energy spectra of fragments from the spontaneous fission of 252Cf has been developed. This model predicts the spectra of these fragments after transmission through any absorber whose thickness and composition are known. The model may be applied to other fissioning elements with minor modifications. Agreement between calculated and experimentally observed peak positions agree to within 5%. The energy shifts due to an absorber may be calculated to within 25% for the thicknesses of foils used.