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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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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.
W. W. Clendenin
Nuclear Science and Engineering | Volume 18 | Number 3 | March 1964 | Pages 351-362
Technical Paper | doi.org/10.13182/NSE64-A20055
Articles are hosted by Taylor and Francis Online.
The dependence of the decay time constant of a thermalized neutron pulse in H2O has been calculated both as a function of buckling and of temperature for the range of temperatures between 23 C and 300 C. Fair agreement between results for two moderator models and experiment has been found for the dependence of the diffusion coefficient on temperature. For higher coefficients in the buckling expansion the agreement is poorer. A new iterative method applicable to any moderator model has been used for the solution of the eigenvalue problem. This method is suited to high-order approximations to the transport equation, a P11 approximation having been used in the present calculations. Convergence is rapid. An advantage is that the diffusion-cooled neutron fluxes are given accurately; these are presented and discussed.
