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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.
M.A. Lomidze, A.E. Gorodetsky, A.P. Zakharov
Fusion Science and Technology | Volume 28 | Number 3 | October 1995 | Pages 1211-1216
Tritium Properties and Interaction with Material | Proceedings of the Fifth Topical Meeting on Tritium Technology In Fission, Fusion, and Isotopic Applications Belgirate, Italy May 28-June 3, 1995 | doi.org/10.13182/FST95-A30574
Articles are hosted by Taylor and Francis Online.
In the model two states for accumulated hydrogen (soluble and molecular) are suggested. Under ion irradiation three reactions (events) take place: recombination of soluble hydrogen on irradiated surface; accumulation of molecular hydrogen; molecular percolation. The first reaction describes recombination under and after irradiation. The second reaction describes molecular hydrogen accumulation as statistical packing of the “traps”. The third one describes molecular percolation as a capturing of one more incoming particle in already packed “trap”, that is accompanied by the reemission of H2, by the devastation of the “trap”, and by the increasing of the irradiated surface. Under steady state for molecular accumulation and surface formation, recombination flux approaches the value of incoming flux and no percolation acts take place. Molecular accumulation approaches the steady state prompter than surface formation. The cross sections for (helium/hydrogen) emission changing over hydrogen to helium beam and vice versa were calculated. Simulation of the model coincides with the experimental data of hydrogen retention, reemission, and post-implanted release.
