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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.
P. Vértes
Nuclear Science and Engineering | Volume 16 | Number 4 | August 1963 | Pages 363-368
Technical Paper | doi.org/10.13182/NSE63-A26546
Articles are hosted by Taylor and Francis Online.
Some problems of the theoretical interpretation of pulsed neutron experiments are investigated in this paper, on the basis of the energy dependent Boltzmann equation. The relation of the infinite medium theory to the finite medium experiments is discussed in details. We perform a calculation in P1L1 approximation in order to determine the form of neutron flux and the extrapolation length. It is demonstrated that the existence of an asymptotic region is not required to apply the infinite medium theory to the finite medium experiments.
