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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.
R. C. Lloyd, B. M. Durst, E. D. Clayton
Nuclear Science and Engineering | Volume 71 | Number 2 | August 1979 | Pages 164-169
Technical Paper | doi.org/10.13182/NSE79-A20407
Articles are hosted by Taylor and Francis Online.
A series of experiments was performed to determine the effect of soluble neutron absorbers on the criticality of water-moderated latticed assemblies. The soluble absorbers used were boron, gadolinium, and cadmium. These materials were mixed with the moderator and reflector of lattices of 4.3-wt%-235U-enriched UO2 fuel pins with stainless-steel cladding. Lattice spacings of 22.9, 27.9, and 33.0 mm, center-to-center, were measured to determine the critical number of rods. The value of keff was computed for each assembly on which criticality was determined. The computed keff value were up to ∼2% above unity in some cases, with the average value for the entire series being 1.007.
