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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.
J. B. Yasinsky
Nuclear Science and Engineering | Volume 39 | Number 2 | February 1970 | Pages 241-256
Technical Paper | doi.org/10.13182/NSE70-A21204
Articles are hosted by Taylor and Francis Online.
The results of a numerical study as to the adequacy of the point kinetics method for analyzing rod-ejection accidents are presented. Two-group slab representations of three different seed-blanket reactors are considered. Five different point kinetics formulations are considered for each fictitious rod-ejection accident considered; each formulation being characterized by the shape functions used to calculate the instantaneous reactivity. From these numerical studies we conclude that the accuracy of a point model, for rapid, nonseparable transients of the type considered, is extremely dependent upon the specifics of the particular model (i.e., on the shape function used), and in general one cannot assume a priori that a specific point model is conservative or nonconservative.