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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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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.
Pierre Benoist
Nuclear Science and Engineering | Volume 77 | Number 1 | January 1981 | Pages 1-12
Technical Paper | doi.org/10.13182/NSE81-A21334
Articles are hosted by Taylor and Francis Online.
In an earlier work, the author presented a theory of the diffusion coefficient in a reactor lattice, leading to expressions valid in full generality. However, for practical purposes it was necessary to admit simplifying assumptions. But now, with the help of modern computers, weaker approximations appear possible. Assuming only two hypotheses, (a) zero-order approximation in , and (b) cylindricalization of the cell, a diffusion coefficient calculation can be transformed into a one-dimensional problem, the solution of which is practically as simple as the calculation of the classical fine structure. The difficulty concerning the reflection of neutrons from the boundary is overcome here; moreover, handling of angular fluxes is avoided, without any approximation. Formulas for the calculation of the diffusion coefficients in the framework of integral transport theory are presented.