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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.
Norman P. Baumann, Willard G. Winn
Nuclear Technology | Volume 72 | Number 3 | March 1986 | Pages 353-358
Technical Paper | Radiation Protection and Health Physics Practices and Experience in Operating Reactors Internationally / Analyse | doi.org/10.13182/NT86-A33774
Articles are hosted by Taylor and Francis Online.
A long-lived gamma source, containing 370 MBq of 232U (72 yr) and 110 MBq of 228Th (1.9 yr), was developed as a permanent replacement for neutron-activated 24Na (15-h) sources that have been used in a 2D(γ,n)1H tritiated water detector. The 228Th, which will build up to 340 MBq in 10 yr and then decay in equilibrium with 232U, emits copious 2614-keV gamma rays for the (γ, n) process. Competing (α, n) backgrounds are reduced by placing the uranium/thorium source in a gold matrix to provide threshold and coulomb barriers against the reaction. The detection limits (∼0.0l-ml D2O) for typical stainless steel pipes (∼2-cm diam) measured with the uranium/thorium source are almost as low as those for comparable 24Na sources, which do not produce (α,n) backgrounds. This minor sensitivity loss can be offset by longer counting times, if necessary. Lower personnel exposure is realized with the new source. Overall, the practical advantages of using a longer lived source strongly favor the use of 232U/228Th instead of 24Na.
