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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.
J. W. Henscheid, E. E. Burdick
Nuclear Science and Engineering | Volume 19 | Number 1 | May 1964 | Pages 39-47
Technical Paper | doi.org/10.13182/NSE64-A19787
Articles are hosted by Taylor and Francis Online.
A semi-empirical equation is used to predict excess reactivity in the ETR as a function of power-time in terms of reactivity parameters which are routinely measured in a mockup of each ETR core in the ETR Critical Facility. Constants in the equation were evaluated by fitting the equation to plots of excess reactivity as a function of power-time obtained for several cores in the ETR. The equation and reactivity measurements fulfill the need for frequent and reliable predictions of core charge life as well as control-rod positions during reactor operation.