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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.
R. Perez-Belles, J. D. Kington, G. Desaussure
Nuclear Science and Engineering | Volume 12 | Number 4 | April 1962 | Pages 505-512
Technical Paper | doi.org/10.13182/NSE62-A26098
Articles are hosted by Taylor and Francis Online.
The value of the effective delayed neutron fraction has been measured for a compact loading of the BSR-I by the boron-substitution technique. The value obtained was 0.0080 ± 0.0002. By adopting the value of the true delayed neutron fraction. β = 0.0064 ± 0.0002, measured by Keepin et al., the ratio of the effective delayed-neutron fraction to the true delayed-neutron fraction is found to be 1.25 ± 0.05. When this quantity was computed by a three-group PDQ-code calculation, the result was 1.25, an agreement which suggests the validity of the computational method.
