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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.
Robert P. Wichner, Roger D. Spence
Nuclear Technology | Volume 70 | Number 3 | September 1985 | Pages 376-393
Technical Paper | Nuclear Safety | doi.org/10.13182/NT85-A15964
Articles are hosted by Taylor and Francis Online.
The degree of vaporization of light water reactor core materials was estimated using a highly idealized procedure involving (a) specification of the phases that are present for both structural and fuel material, (b) estimation of the vapor pressures exerted by the individual components of each phase, and (c) assuming a degree of vaporization of each phase constituent, allowing equilibration between gaseous and condensed species within the assumed pressure vessel volume. Using this procedure, the aerosol was estimated to consist mainly of silver, indium oxide, cesium hydroxide, and cadmium for pressurized water reactors and cesium hydroxide, cesium iodide, and tellurium for boiling water reactors. If boron is included in the thermodynamic estimate, then boron will significantly alter or dominate the composition of the aerosol in the form of boron oxide and cesium borate. The structural materials make up <9% of the aerosol at 36 to 57 kg, but this figure is in good agreement with estimates from severe accident sequence analysis studies (17 kg) and from Parker (10.7 kg). The SASCHA data are used in NUREG-0772 and give much higher estimates at 295 and 250 kg.
