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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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Latest News
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.
B. G. Chidley, T. J. Manuel, P. R. Tunnicliffe
Nuclear Science and Engineering | Volume 17 | Number 1 | September 1963 | Pages 47-54
Technical Paper | doi.org/10.13182/NSE63-A17209
Articles are hosted by Taylor and Francis Online.
A previously described experimental method of determining initial conversion ratios in reactor lattices has been improved. Measurements have been made on D2O-cooled, 19-element UO2, heavy-water lattices at pitches of 18, 21, 24, 28, and 36 cm. The initial conversion ratios obtained were 0.9547 ± 0.0086, 0.8578 ± 0.077, 0.7671 ± 0.0069, 0.7416 ± 0.0067, and 0.6853 ± 0.0062 and the resonance escape probabilities derived are 0.8226, 0.8656, 0.9104, 0.9228, and 0.9511, respectively. The fast fission factors obtained for the 18, 24, 28, and 36 cm lattice pitches were 1.0283, 1.0265, 1.0253, and 1.0247.
