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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.
F. T. Avignone III, L. P. Hopkins, Z. D. Greenwood
Nuclear Science and Engineering | Volume 72 | Number 2 | November 1979 | Pages 216-221
Technical Paper | doi.org/10.13182/NSE79-A19465
Articles are hosted by Taylor and Francis Online.
The theoretical beta spectrum of the thermal fission fragments of 235U in secular equilibrium was calculated using recent fission yields, nuclear decay scheme data, and very recent semi-empirical mass formulas to predict beta Q values of nuclides with unknown energy level structure. Better agreement with experiment is achieved when these isotopes are assumed to contain all of the excited states of isotopes with known decay schemes with the same atomic number Z and with neutron numbers N differing by even integers. The beta branching ratios for the unknown isotopes were assumed to be the renormalized collection of branching ratios found in all known isotopes of the families described above. The results obtained with these narrower restrictions are in better general agreement with experiment than those that replace the excited states and branching ratios of the unknown nuclides with those obtained by taking broad averages over known isotopes. There still appears to be some disagreement between theory and experiment, particularly at the high-energy end of the spectrum.
