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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.
T. X. Bruce Qu, Thomas E. Blue, C. K. Chris Wang, Reinhard A. Gahbauer
Nuclear Technology | Volume 91 | Number 3 | September 1990 | Pages 404-412
Technical Paper | Radioisotopes and Isotope Separation | doi.org/10.13182/NT90-A34461
Articles are hosted by Taylor and Francis Online.
Previously, a neutronic study of an accelerator-based epithermal neutron irradiation facility (AENIF) for boron neutron capture therapy (BNCT) was performed using three-dimensional Monte Carlo transport calculations. The major components of the AENIF are a radio-frequency quadrupole proton accelerator, a 7Li target, and a moderator assembly. Neutrons are generated by bombarding the 7Li target with 2.5-MeV protons. The neutrons emerging from the 7Li target are too energetic to be used for BNCT and are moderated as they traverse the moderator assembly to the patient. The design of a moderator assembly for an AENIF for the treatment of glioblastoma is reviewed, and this design is compared with the design of a moderator as sembly for an accelerator thermal neutron irradiation facility (A TNIF) for the treatment of superficial melanoma. The ATNIF moderator assembly consists of a 50-cm-high × 30-cm-diam cylinder of D2O, surrounded on its top and sides by a 40-cm-thick graphite reflector. This moderator assembly creates, at the surface of a large phantom at its irradiation port, a boron absorbed dose rate of (3.2 ± 0.2) cGy/(min · mA), for a tumor 10B concentration of 24 µg of10B per gram of tissue. For a single-session dose equivalent of 40 Sv to the tumor, the treatment time is 13 min for a 30-mA proton beam. With different moderator assemblies, a 30-mA, 2.5-MeV proton accelerator can be used to treat both superficial and deep lesions from melanomas and gliomas.
