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Division Spotlight
Fuel Cycle & Waste Management
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.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
R. D. McKnight
Nuclear Science and Engineering | Volume 75 | Number 1 | July 1980 | Pages 111-125
Technical Note | doi.org/10.13182/NSE80-A20322
Articles are hosted by Taylor and Francis Online.
A detailed validation study of the SDX fast reactor cell homogenization code, Benoist anisotropic diffusion coefficients, and an associated three-dimensional to one-dimensional unit cell modeling procedure has been in progress. These earlier results have investigated the standard zero power reactor (ZPR) plate-type unit cell The present study represents a complimentary validation effort for the ZPR pin calandria-type unit cell. The unit cell loading selected for this work consisted of a 5.08- × 5.08- × 30.48-cm voided calandria loaded with a 4 × 4 array of 0.957-cm (diam) × 15.24-cm mixed-oxide rods (15% PuO2/UO2). This unit cell was used in the pin zone measurements of the ZPR gas-cooled fast reactor program and also in the sodium-voided pin zone measurements of ZPR-6 Assembly 7. The validation effort consists of direct comparison with results of VIM (continuous energy Monte Carlo) calculations. The SDX/Gelbard methods have been shown to adequately predict both nonleakage and leakage effects for the voided pin calandria unit cell.
