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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Work advances on X-energy’s TRISO fuel fabrication facility
Small modular reactor developer X-energy, together with its fuel-developing subsidiary TRISO-X, has selected Clark Construction Group to finish the building construction phase of its advanced nuclear fuel fabrication facility, known as TX-1, in Oak Ridge, Tenn. It will be the first of two Oak Ridge facilities built to manufacture the company’s TRISO fuel for use in its Xe-100 SMR. The initial deployment of the Xe-100 will be at Dow Chemical Company’s UCC Seadrift Operations manufacturing site on Texas’s Gulf Coast.
James A. Davis
Nuclear Science and Engineering | Volume 25 | Number 2 | June 1966 | Pages 189-197
Technical Paper | doi.org/10.13182/NSE66-A17736
Articles are hosted by Taylor and Francis Online.
Approximate vacuum boundary conditions for a PN approximation are obtained by variational methods. Two stationary principles are proposed, one having what we shall call “odd” Marshak conditions as its natural boundary conditions, and the other having “even” Marshak conditions as its natural boundary conditions. The principles are valid for arbitrary geometry. The odd Marshak conditions are seen to be suitable for an odd-order PN approximation and the even Marshak conditions for an even-order PN approximation. The odd Marshak conditions are precisely the conditions obtained by Vladimirov from an extremum principle in which certain restrictions are imposed on the source and scattering. The present treatment contains no such restrictions.
