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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.
S. Tosti, A. Colombini, V. Violante, G. Simbolotti
Fusion Science and Technology | Volume 28 | Number 3 | October 1995 | Pages 755-760
Tritium Processing | 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-A30495
Articles are hosted by Taylor and Francis Online.
A computer model has been developed to evaluate tritium permeation to coolant and in vanadium tubes inventory in Safety and Environmental Assessment of Fusion Power (SEAFP) blanket. The mean tritium partial pressure in gaseous breeder phase are in the range from 0.5 to 5 Pa for helium purge gas velocity from 0.1 to 0.4 m/s; in these conditions the tritium permeation to coolant changes from 32.8 to 16.4 g/day and the tritium inventory in vanadium tubes from 4000 to 2000 g. The H/T ratio involves a relevant tritium permeation variation: with 0.2 m/s helium purge gas velocity varying the H/T ratio from 100 to 50 the tritium permeation to coolant ranges from 23.2 to 32.7 g/day. The analysis shows that defects free thin permeation barriers (SiC and Al2O3) are very effective to making negligible the tritium permeation to coolant and the tritium inventory in tubes.
