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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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Latest News
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.
Elias P. Gyftopoulos, Jacques Devooght
Nuclear Science and Engineering | Volume 10 | Number 4 | August 1961 | Pages 372-376
doi.org/10.13182/NSE61-A15381
Articles are hosted by Taylor and Francis Online.
Space-independent, conventional, nonlinear reactor dynamics equations are derived by a second-order perturbation method. A general criterion is derived indicating the conditions under which it is purposeful to use the nonlinear equations as such. It is shown that the range of validity of nonlinear dynamics is not unlimited and in case of large deviations from equilibrium higher order perturbation terms are required.
