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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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 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. That's the same amount of HALEU—900 kg—that the company today announced it has delivered to the DOE, completing Phase II of its contract. According to Centrus, the contract extension, which allows the company to begin Phase III, is valued at about $110 million through June 30, 2026.
Keiichiro Tsuchihashi, Yukio Ishiguro, Kunio Kaneko
Nuclear Science and Engineering | Volume 73 | Number 2 | February 1980 | Pages 164-173
Technical Paper | doi.org/10.13182/NSE80-A18696
Articles are hosted by Taylor and Francis Online.
A simplified method based on the intermediate resonance approximation is proposed to deal with the double heterogeneity encountered in design calculations of high-temperature gas-cooled reactors. First, a fuel rod with grain structure is homogenized by introducing an equivalent homogeneous material, in the form of an intermediate resonance approximation, that contains a fictitious moderator substituted for both the grain heterogeneity and the scattering in moderator region. Second, the cluster configuration of the homogenized rods is treated by use of the fictitious moderator. This method is shown to offer a convenient and simple means with good accuracy and short computing time when combined with the “table look-up” method of resonance shielding factors.
