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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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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.
Joel H. Ferziger
Nuclear Science and Engineering | Volume 14 | Number 3 | November 1962 | Pages 244-248
doi.org/10.13182/NSE62-A26213
Articles are hosted by Taylor and Francis Online.
An extension of the methods for computing resonance integrals given by Chernick and Vernon (8) and Nordheim et al. (9) to the case of nonuniform temperature distributions in the absorber is given. Formally, the procedure is quite similar to the previous work and utilizes the same approximations: absorbed neutrons are broken into two groups according to whether their previous collisions were in the absorber or in the moderator; both the narrow resonance (NR) and infinite mass (NRIA) approximations are developed. The effect of nonuniform temperature distribution is to modify the escape probabilities required. The present calculation requires escape probabilities for lumps which contain nonuniform sources and/or cross sections. Methods of computing these escape probabilities are presented.