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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.
C. W. Maynard
Nuclear Science and Engineering | Volume 10 | Number 2 | June 1961 | Pages 97-101
Technical Paper | doi.org/10.13182/NSE61-A25945
Articles are hosted by Taylor and Francis Online.
In solving two-dimensional one-energy transport problems, it is often necessary to utilize Monte Carlo calculations in situations where this technique converges very slowly. In problems with regionwise constant sources where the required result is the flux at a point or an integral of the flux over a region or surface, the reciprocity theorem can be used to determine an auxiliary problem which yields the same information while in many cases improving the statistics appreciably. The relations required in choosing the auxiliary problem are derived. The required integrals and statistical errors are stated in terms of the results for the auxiliary problem. Examples are given to illustrate the application of these ideas to a flux peaking situation and to the absorption in a small region. The extension of this procedure to energy-dependent cases is discussed briefly.