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Conference Spotlight
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.
P. B. Parks, D. J. Pellarin, N. H. Prochnow, N. P. Baumann
Nuclear Science and Engineering | Volume 33 | Number 2 | August 1968 | Pages 209-217
Technical Paper | doi.org/10.13182/NSE68-A20658
Articles are hosted by Taylor and Francis Online.
Thermal-neutron diffusion coefficients for H2O and D2O were determined from static measurements of the neutron relaxation length in boron poisoned H2O and D2O and pulsed measurements of the neutron die-away in different sized containers of these two moderators. The coefficients derived for H2O are: These results agree well with previously reported coefficients, fairly well with Honeck's calculations, and very well with Dorning's more recent calculations. The diffusion coefficients for D2O were derived from data in the range of (equivalent) poison concentrations, ∑a(B) = −0.04 to +0.04/cm. Restricting the data to these limits avoids possible difficulties associated with the approach to the Corngold limits at κ = (∑t)min and . The coefficients derived for D2O are: Unlike previous experiments, these results indicate no discrepancy between pulsed and static determinations of D0 for D2O.
