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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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TVA nominees promise to support advanced reactor development
Four nominees to serve on the Tennessee Valley Authority Board of Directors told the Senate Environment and Public Works Committee that they support the build-out of new advanced nuclear reactors to meet the increased energy demand being shouldered by the country’s largest public utility.
R. C. Lloyd, E. D. Clayton
Nuclear Science and Engineering | Volume 52 | Number 1 | September 1973 | Pages 73-75
Technical Paper | doi.org/10.13182/NSE73-A23289
Articles are hosted by Taylor and Francis Online.
A series of criticality experiments have been completed with plutonium nitrate solutions made up from extremely high burnup fuel (239Pu isotopic concentration <½ total Pu). The measurements were performed on a large, 61-cm-diam, water-reflected, cylindrical vessel. The critical experiment data were analyzed by means of the KENO Monte Carlo code utilizing both ENDF/B-H and -III cross sections; the computed criticality factors were in the range of 1.6 to 1.9% above unity. The effects of the various heavy element isotopes on criticality were analyzed. The results show the importance of properly accounting for, and treating, the effects of each of the various isotopes in computing criticality. Even the presence of as little as 1% of 241 Am can cause a change in the reactivity of the solutions used in these experiments by ∼1%.
