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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.
W. W. CLENDENIN
Nuclear Science and Engineering | Volume 13 | Number 1 | May 1962 | Pages 46-53
Technical Paper | doi.org/10.13182/NSE62-A26127
Articles are hosted by Taylor and Francis Online.
Explicit expressions for the Marshak boundary conditions and vacuum gap conditions are developed through the P5 approximation. A blackness theory is developed for the accurate treatment of regions with high absorption of heavy elements. The relevant coefficients are expressed in terms of solutions of one velocity problems for which boundary conditions are given.
