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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.
Ian J. Hastings, Elio Mizzan, Alan M. Ross, John R. Kelm, Real J. Chenier, D. H. Rose, J. Novak
Nuclear Technology | Volume 68 | Number 1 | January 1985 | Pages 40-47
Technical Paper | Nuclear Fuel | doi.org/10.13182/NT85-A33565
Articles are hosted by Taylor and Francis Online.
Fragments of UO2 fuel pellets extracted from irradiated elements were heated in air at 175 to 275 °C for times up to 800 h. Unirradiated pellets and fragments were studied for comparison. Pretest burnup of the irradiated fuel was typically 190 MW-h/kgU (7900 MWd per tonne of uranium) at a maximum linear power of 45 kW/m. The fuel had been discharged for 1 to 3 yr. The maximum weight gain was at 275 °C, ∼4% in 70 h, indicating 100% conversion to U3O8. The activation energy for the oxidation process at 175 to 275 °C was 130 ± 10 kJ/mol. There was a strong effect of prior irradiation on oxidation rate; the weight gain at 250 °C was about a factor of 6 greater in irradiated compared with unirradiated fuel. There was also an effect of fragment size on oxidation rate. Also, weight gains of fragments from a naturally defected element were less than those for fragments from intact fuel, consistent with prior oxidation in the defected state.
