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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.
K. Wisshak, F. Käppeler
Nuclear Science and Engineering | Volume 69 | Number 1 | January 1979 | Pages 47-54
Technical Paper | doi.org/10.13182/NSE79-A21284
Articles are hosted by Taylor and Francis Online.
The subthreshold fission cross section of 240Pu was measured in the energy range from 10 to 250 keV, using 235U as a standard. Neutrons were produced via the 7Li(p,n) and T(p,n) reaction with the Karlsruhe 3-MV pulsed Van de Graaff accelerator. Fission events were registered by detecting fission neutrons with an NE-213 liquid scintillator with pulse-shape discriminator equipment. The high neutron flux available at flight paths of ∼67 and 135 mm allowed for a statistical accuracy of 1 to 3% together with a moderate energy resolution of ∼10 to 20 ns/m. The overall accuracy achieved is between 7 and 9%. The data show a distinct structure in the cross section, as indicated by poor statistics in previous measurements.
