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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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.
D. Saphier
Nuclear Science and Engineering | Volume 47 | Number 3 | March 1972 | Pages 275-289
Technical Paper | doi.org/10.13182/NSE72-A22414
Articles are hosted by Taylor and Francis Online.
A new hybrid method was developed for the solution of the one-dimensional time-dependent diffusion equation in four energy and four delayed-neutron groups. Using this method it is possible to reduce the cost per problem solved by an order of magnitude compared with commonly used digital methods. The solution is based on discretizing the multigroup diffusion equation with respect to the spatial variable while leaving the time variable continuous. The simple coupled time-dependent differential equations so obtained are integrated continuously and in parallel for each of the reactor regions. The regional boundary values are updated from iteration to iteration until convergence is obtained. Two examples are presented in which the hybrid and digital solutions are compared for a fast plutonium oxide fueled reactor. The agreement between the hybrid and digital solution is fairly good.