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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Latest News
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.
R. G. Alsmiller, Jr., J. Barish
Nuclear Science and Engineering | Volume 69 | Number 3 | March 1979 | Pages 378-388
Technical Paper | doi.org/10.13182/NSE79-A19956
Articles are hosted by Taylor and Francis Online.
Multigroup cross sections (47 n groups, 21 gamma-ray groups) in ANISN format for neutron energies from thermal to 60 MeV and for the elements hydrogen, 10B, 11B, carbon, oxygen, silicon, calcium, chromium, iron, and nickel are described. A P5 Legendre expansion is used at energies , and a P3 Legendre expansion is used at energies . Below 14.9 MeV, the cross sections are from the Radiation Shielding Information Center's fusion energy cross-section library. Above this energy, differential elastic scattering cross-section data from optical model calculations are used, and differential nonelastic scattering data from the intranuclear-cascade-evaporation model are used. Calculated results of the dose equivalent versus depth in the shield from a point isotropic source at the center of a 366-cm-thick spherical shell heavy concrete (density = 3.6 g cm−3) shield are presented. The energy distribution of the source neutrons is approximately that from a Li(D, n) neutron radiation damage facility.