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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NNSA awards BWXT $1.5B defense fuels contract
The Department of Energy’s National Nuclear Security Administration has awarded BWX Technologies a contract valued at $1.5 billion to build a Domestic Uranium Enrichment Centrifuge Experiment (DUECE) pilot plant in Tennessee in support of the administration’s efforts to build out a domestic supply of unobligated enriched uranium for defense-related nuclear fuel.
Louis B. Freeman, Herbert C. Hecker
Nuclear Science and Engineering | Volume 80 | Number 2 | February 1982 | Pages 338-341
Technical Note | doi.org/10.13182/NSE82-A21437
Articles are hosted by Taylor and Francis Online.
In a thorium-fueled reactor, the conversion of 232Th to 233U involves the intermediate nuclide 233Pa. This isotope has a significant reactivity effect in any thorium reactor, especially one with an important epithermal flux component. The light water breeder reactor, operating in the Shippingport atomic power station, is a 233U-Th reactor with about half the power produced at energies above thermal. The reactivity effect of full-power equilibrium 233Pa has been inferred from critical position measurements and control element reactivity worths to be ∼2.5% Δρ in this reactor, confirming calculational predictions.