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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Ho Nieh nominated to the NRC
Nieh
President Trump recently nominated Ho Nieh for the role of commissioner in the Nuclear Regulatory Commission through the remainder of a term that will expire June 30, 2029.
Nieh has been the vice president of regulatory affairs at Southern Nuclear since 2021, though he is currently working as a loaned executive at the Institute of Nuclear Power Operations, where he has been for more than a year.
Nieh’s experience: Nieh started his career at the Knolls Atomic Power Laboratory, where he worked primarily as a nuclear plant engineer and contributed as a civilian instructor in the U.S. Navy’s Nuclear Power Program.
From there, he joined the NRC in 1997 as a project engineer. In more than 19 years of service at the organization, he served in a variety of key leadership roles, including division director of Reactor Projects, division director of Inspection and Regional Support, and director of the Office of Nuclear Reactor Regulation.
J. C. Manaranche, D. Mangin, L. Maubert, G. Colomb, G. Poullot
Nuclear Science and Engineering | Volume 71 | Number 2 | August 1979 | Pages 154-163
Technical Paper | doi.org/10.13182/NSE79-4
Articles are hosted by Taylor and Francis Online.
The development of pressurized water reactors and boiling water reactors in the world necessitates complete critical experiments on this type of fuel for the validation of the methods used in criticality calculations and to resolve the various related problems. This paper presents the first results obtained at the Critical Mass Laboratory at Valduc during critical approaches achieved with lattices of 4.75-wt%-235U-enriched UO2 rods in water. Four square pitches (12.6, 16.0, 21.0, and 25.2 mm) and three triangular pitches (13.5, 17.2, and 22.6 mm) have been studied, and various configurations with fuel rods removed were investigated. Benchmark calculations are presented.
