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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.
S. H. Chan, H. H. Tseng
Nuclear Science and Engineering | Volume 71 | Number 2 | August 1979 | Pages 215-227
Technical Note | doi.org/10.13182/NSE79-A20415
Articles are hosted by Taylor and Francis Online.
In analyzing radiant energy exchange between fuel and coolant in a reactor, it is necessary to know the reflection, absorption, and emission characteristics of the fuel and its interface with the coolant. Because of the unavailability and great uncertainty of these radiation properties, they are calculated from the electromagnetic theory of optics, and results are presented here. Depending on the contacting medium, six types of surfaces received consideration. They are the interfaces between uranium dioxide and sodium, uranium dioxide and steel, uranium dioxide and a gas, water and a gas, steel and a gas, as well as sodium and a gas. The spectral interface reflectance and the spectral absorptance from one side of the medium to the other side are evaluated for all wavelengths. These spectral properties are further integrated to yield the total hemispherical properties for a black body source over a temperature range from 1200 to 6000 K. Comparisons are made with available experimental data or calculated values, and the agreement is found to be generally good.
