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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
Standards Program
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.
M. H. Kalos
Nuclear Science and Engineering | Volume 16 | Number 2 | June 1963 | Pages 227-234
Technical Paper | doi.org/10.13182/NSE63-A26504
Articles are hosted by Taylor and Francis Online.
It is proposed that importance sampling may be carried out using an approximate analytic form for the importance function. An altered Boltzmann kernel may then be computed. Choosing from this altered kernel is facilitated, in part, by particle splitting. The method is carried out in detail for neutron penetration in hydrogen slabs. Results are given for dose buildup and energy spectrum for slab depths up to 179 mean free paths for 8.1 Mev neutrons.
