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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.
Curtis G. Chezem
Nuclear Science and Engineering | Volume 8 | Number 6 | December 1960 | Pages 652-669
Technical Paper | doi.org/10.13182/NSE60-A25851
Articles are hosted by Taylor and Francis Online.
Certain conflicts arising from previous measurements of neutron flux parameters in the equilibrium spectrum of natural uranium have been resolved. The parameters which were investigated are listed below along with “best” values as measured in this work. , The experiment was performed at the Pajarito critical assemblies facility utilizing two exponential columns of natural uranium, each 30.7 in. high, having diameters of 15 and 21 in. and excited by a small fast reactor. The system was outdoors, elevated some 11 ft above the ground level to reduce flux perturbations due to backscattering of neutrons. Perturbation corrected measurements in both columns made by several detection methods and with various source spectra agree to within experimental error and are consistent with calculated values.
