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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Wright officially sworn in for third term at the NRC
The Nuclear Regulatory Commission recently announced that David Wright, after being nominated by President Trump and confirmed by the Senate, was ceremonially sworn in as NRC chair on September 8.
This swearing in comes more than a month after Wright began his third term on the commission; he began leading as chair July 31. His term will conclude on June 30, 2030.
D. Kontogeorgakos, I. E. Stamatelatos
Nuclear Technology | Volume 170 | Number 3 | June 2010 | Pages 460-464
Technical Note | Fission Reactors | doi.org/10.13182/NT10-A10331
Articles are hosted by Taylor and Francis Online.
The aim of this study was to validate a Monte Carlo-based model of the Greek Research Reactor-1 (GRR-1) developed with the MCNP5 code. The GRR-1 core was modeled in detail using the exact geometry without approximations. The inventory of the core was derived using the WIMS-ANL code, taking into account the different 235U burnup of each fuel assembly. The model was validated against experimentally determined control rod reactivity worth and neutron flux measurements performed in various irradiation positions. The ratio of the calculated-to-measured integral reactivity of each of the five control rods was found to be 0.972 ± 0.151, 1.083 ± 0.168, 1.156 ± 0.179, 0.874 ± 0.137, and 1.097 ± 0.170. The calculated-to-measured thermal neutron flux ratios ranged from 0.83 ± 0.04 to 1.22 ± 0.07. Therefore, good agreement between MCNP calculated and experimental values was observed. The GRR-1 core model will be fully implemented in the design of material irradiation experiments along with reactor safety and fuel management studies.
