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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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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.
Henri B. Smets
Nuclear Science and Engineering | Volume 11 | Number 2 | October 1961 | Pages 133-141
Technical Paper | doi.org/10.13182/NSE61-A28058
Articles are hosted by Taylor and Francis Online.
Topological methods are used in the study of the effect of burnable fission products on power reactor kinetics. Taking as an example three different problems, it is shown that power is controlled when the amount of inserted reactivity is small: properties of stability in the large and of boundedness are found in the case of a short-lived absorbing fission product, burnable delayed neutron emitters, and the xenon-controlled reactor.
