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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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Ho Nieh, TVA board members, and nuclear fuel recycling bill head to Senate floor
Nieh
Ho Nieh, the Trump administration’s nominee to be a member of the Nuclear Regulatory Commission, and four new board members of the Tennessee Valley Authority were approved in a vote today by the Senate Environment and Public Works Committee and head to the Senate floor for a final vote.
The committee also voted to advance to the Senate floor the Nuclear REFUEL Act of 2025 (S. 2082), which would smooth the regulatory pathway for recycling used nuclear fuel.
President Donald nominated Nieh on July 30 to serve as NRC commissioner for the remainder of a term set to expire June 30, 2029, which was held by former NRC commissioner Chris Hanson, who Trump fired in June.
Walter H. D'Ardenne, Henry E. Bliss, David D. Lanning, Irving Kaplan and Theos J. Thompson
Nuclear Science and Engineering | Volume 32 | Number 3 | June 1968 | Pages 283-291
Technical Paper | doi.org/10.13182/NSE68-A20210
Articles are hosted by Taylor and Francis Online.
Reactor physics parameters were measured in three heavy water lattices consisting of 0.250-in.-diam, 1.03 wt% 235U metal fuel rods in triangular arrays spaced at 1.25, 1.75, and 2.50 in. The following quantities were measured in each lattice: the ratio of epicadmium to subcadmium radiative captures in 238U (ρ28); the ratio of epicadmium to subcadmium fissions in 235U (δ25); the ratio of radiative captures in 238U to fissions in 235U (C); and the fissions in 238U to fissions in 235U (δ28). These experimental results were used to calculate the following reactor physics parameters for each lattice: the resonance escape probability p, the fast fission factor ϵ, the multiplication factor for an infinite system k∞, and the initial conversion ratio C. Analytical results obtained by using THERMOS and GAM-I are in fair agreement with the experimental results.