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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.
G. E. Hansen, H. C. Paxton, D. P. Wood
Nuclear Science and Engineering | Volume 8 | Number 6 | December 1960 | Pages 570-577
Technical Paper | doi.org/10.13182/NSE60-A25843
Articles are hosted by Taylor and Francis Online.
Critical configurations have been established with enriched uranium in the form of squat 15.0-in. diameter cylinders and elongated 3.24-in. diameter cylinders. These cores were reflected by depleted uranium, polyethylene, graphite, and water; also, the squat cylinder was unreflected and reflected by beryllium of various thicknesses. Critical systems of plutonium were squat 6.0-in. diameter cylinders and elongated 2.25-in. diameter cylinders reflected by normal uranium, graphite, water, and in one case, polyethylene. Observed critical heights and diameters were corrected to correspond to standard enriched-uranium and plutonium densities and concentrations. These are tabulated along with effective extrapolation distances.
