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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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.
J. B. Yasinsky, L. R. Foulke
Nuclear Science and Engineering | Volume 44 | Number 1 | April 1971 | Pages 72-85
Technical Paper | doi.org/10.13182/NSE71-A18907
Articles are hosted by Taylor and Francis Online.
It is shown that the use of the standard spatial-differencing method when applied to space-time diffusion problems arising as the materials within a reactor are displaced can result in solutions which display a nonphysical time dependence. This irregular time dependence occurs when the spatial mesh and timestep are such that it takes several time steps for a movable material interface to move between two spatial meshpoints. New spatial difference equations, based on a specified piecewise polynomial flux behavior between meshpoints, are developed for the space-time group diffusion equations. Numerical studies show that these new difference equations eliminate the nonphysical time dependence of the solution for movable material problems. In addition, it is shown that for such problems the solutions resulting from the new difference equations are almost as accurate as solutions obtained using the standard difference equations with a much finer spatial mesh.
