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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
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.
