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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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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.
C. W. Griffin
Nuclear Science and Engineering | Volume 14 | Number 3 | November 1962 | Pages 304-311
doi.org/10.13182/NSE62-A26220
Articles are hosted by Taylor and Francis Online.
The prompt power coefficient resulting from the Doppler effect and fuel element bowing of unrestrained fuel clusters in the Th-U second core of the SRE was measured by performing power and flow ramp tests. Individual components of bowing magnitude and the Doppler coefficient were isolated. Fuel bowing resulted from three effects: axial temperature gradient, radial temperature gradient, and coolant flow. Magnitude of the flow effect was independent of power. Bowing was restrained by wrapping each cluster with a helically wound stainless steel wire. This reduced the power coefficient from +9¢/Mw to −2.5¢/Mw. The measured Doppler coefficient was −0.23¢/°F.
