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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.
Gerald S. Lellouche
Nuclear Science and Engineering | Volume 12 | Number 4 | April 1962 | Pages 482-489
Technical Paper | doi.org/10.13182/NSE62-A26095
Articles are hosted by Taylor and Francis Online.
The effect of xenon and temperature on reactor dynamics in a free system is extended to include an explicit spatial dependence. The stability boundaries are determined in linear approximation for solid and annular cylindrical systems for several core sizes. Annular stability is found to be the hardest to achieve. It is shown that several terms in the series expansion of the fundamental are necessary to give a good representation of the stability of the first harmonic.
