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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.
A. Hemmendinger, C. E. Ragan, Jon M. Wallace
Nuclear Science and Engineering | Volume 70 | Number 3 | June 1979 | Pages 274-280
Technical Paper | doi.org/10.13182/NSE79-A20148
Articles are hosted by Taylor and Francis Online.
The specific production of tritium in a 600-mm-diam sphere of 6LiD irradiated by a central source of 14-MeV neutrons has been determined by measuring the tritium radioactivity in samples of 6LiH and 7LiH embedded in the sphere. Results are reported for several samples of each isotope at each of five different radii in the assembly. The entire process of decomposing the LiH samples, transferring the evolved gas into counters, and determining the decay rate was standardized by processing LiH samples irradiated by thermal neutrons, for which the 6Li(n,α) cross section is well known. These experiments provide benchmark measurements for checking calculations of neutron transport and tritium production in 6LiD. Tritium production in each ampule, as calculated using a three-dimensional Monte Carlo code, is in reasonable agreement with the experiment. For 7Li, discrepancies between calculation and experiment seem to be due to errors in the tritium production cross sections.
