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2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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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.
S. Tassan
Nuclear Science and Engineering | Volume 26 | Number 2 | October 1966 | Pages 271-276
Technical Paper | doi.org/10.13182/NSE66-A28169
Articles are hosted by Taylor and Francis Online.
Thermal spectrum measurements in 1% enriched uranium, 0.387-in. diam rod lattices, light water moderated, have been performed by the lutetium activation method in order to test the usefulness of this technique in not-well-thermalized lattices. Dysprosium-164 and 175Lu were used as reference thermal-neutron detectors. The experimental results are presented as the average values of the normalized (lattice/Maxwellian) activation ratios of 176Lu/Dy and 176Lu/ 175Lu with the pertinent cadmium-ratios, in the fuel and in the moderator over the H2O/U range from 1:1 to 4:1. The agreement with the results of a calculation performed using the THERMOS code is satisfactory. It is concluded that the 176Lu/Dy set appears to be adequate for the thermal spectrum analysis of light-water-moderated lattices, while the 175Lu/Dy set can provide rather accurate integral data for the epithermal component of the neutron spectrum.
