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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.
Eric V. Brown, Leonard W. Gray, D. William Tedder
Nuclear Technology | Volume 89 | Number 3 | March 1990 | Pages 328-340
Technical Paper | Chemical Processing | doi.org/10.13182/NT90-A34370
Articles are hosted by Taylor and Francis Online.
A computer model of an air-lift dissolver was developed to predict the dissolution rates for plutonium oxide (PuO2), dysprosium oxide (Dy2O3), and incinerator ash. This model combines surface kinetics with mass transfer effects to obtain overall rate expressions. The mass transfer coefficients are related to several major process variables. These predictions were compared with experimental tests at Savannah River Laboratory using simulated ash and Dy2O3 as a surrogate for refractory PuO2. The present version of the model overestimates the residual fluoride concentrations in dissolver effluents by ∼50% for several reasons, which are discussed. The minimum air sparge rates to achieve liquid circulation in the dissolver are predicted quite well, within ± 6%. The nonvolatile dissolved solids are estimated to within ±5 to 20%. Dysprosium dissolution is predicted to within ±10%. Dysprosium oxide is a poor surrogate for refractory PuO2.
