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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.
Shi-Chien Lin, Michiko Hamasaki, Yii-Der Chuang
Nuclear Science and Engineering | Volume 71 | Number 3 | September 1979 | Pages 237-250
Technical Paper | doi.org/10.13182/NSE79-A19061
Articles are hosted by Taylor and Francis Online.
We studied the dispersion and spheroidization treatment of zirconium hydride in reactor-grade zirconium alloys. Our aim was to find a workable way to improve the properties of Zircaloys. A scanning electron microscope was used to observe zirconium hydride precipitated in specimens of Zircaloy-2 and Zircaloy-4. We also examined hardness and corrosion before and after spheroidization in hydrogen. Experimental procedures and results can be summarized as follows. The specimens of low hydrogen concentration (<680 ppm) were hydrided at 420°C for 15 h, then cooled at a rate of <5 °C/min, and finally spheroidized at 520°C, just below the eutectoid temperature, for 20 to 72 h (the exact time required depending on the concentration of hydrogen). Successful spheroidization of zirconium hydride was obtained. The specimens of high hydrogen concentration (680 to 2210 ppm) were cycled near the eutectoid temperature, i.e., 547° C, for six to eight times and then annealed f or 30 to 128 h (the exact time depending on hydrogen concentration); finally, the specimens were slowly cooled at a rate of <5°C/min. It was found that for specimens with a hydrogen concentration ranging from 1000 to 2000 ppm, the heat treatment described above is satisfactory. But for specimens with a hydrogen concentration >2000 ppm, a heat treatment time >128 h at 520°C is required. The corrosion resistance of a spheroidized specimen was better than that of a specimen with platelet hydrides.