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Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Latest News
DOE extends Centrus’s HALEU production contract by one year
Centrus Energy has announced that it has secured a contract extension from the Department of Energy to continue—for one year—its ongoing high-assay low-enriched uranium (HALEU) production at the American Centrifuge Plant in Piketon, Ohio, at an annual rate of 900 kilograms of HALEU UF6. According to Centrus, the extension is valued at about $110 million through June 30, 2026.
G. C. Pomraning
Nuclear Science and Engineering | Volume 69 | Number 1 | January 1979 | Pages 6-13
Technical Paper | doi.org/10.13182/NSE79-A21279
Articles are hosted by Taylor and Francis Online.
Analytic estimates are given for the angular dependence of the neutron (or photon) flux in toroidal geometry arising from the toroidal character of the configuration. The model used in the analysis is the one-group homogeneous diffusion model The toroidal angular effects in the local flux are shown to be first order in ϵ, the inverse aspect ratio, whereas angular effects occurring in spatial integrals of the flux are found to be of order ϵ2. An analytic expression for the Green's function for diffusion equation in toroidal geometry is given correct to order ϵ2, and typical numerical results are shown. A transformation of the scalar flux is presented that removes all angular dependence from the streaming term in the diffusion equation and removes the angular dependence from the absorption term correct to order ϵ. The overall conclusion reached is that angular toroidal effects are not simply characterized.
