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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.
John F. Geldard, Adolph L. Beyerlein
Nuclear Technology | Volume 89 | Number 3 | March 1990 | Pages 318-327
Technical Paper | Chemical Processing | doi.org/10.13182/NT90-A34369
Articles are hosted by Taylor and Francis Online.
The mathematical basis for two new computer codes, PULSER and PULMAT, is described. The PULSER code simulates the temporal and steady-state concentration profiles in pulsed column contactors using the Purex process. The CPU times needed for these calculations are at least 50 times less than those using the previously described CUSEP code. This is obtained by recognizing that effects due to pulsing occur on a much faster time scale than those due to steady flow and they can be approximated as occurring instantaneously. Separation of the time scales allows the formulation of simple flow equations for pulsed column contactors. In addition, a matrix method can be devised that makes possible direct calculation of the steady-state concentration profiles, resulting in very short CPU times. The code that performs these calculations is called PULMAT. Both codes have been used to generate concentration profiles in several extraction (A-type) and stripping (E-type) contactors and in a partitioning (B-type) contactor. These results are compared with results obtained using the CUSEP computer code and with other results where available.
