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Division Spotlight
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.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Douglas W. Akers, Richard K. McCardell
Nuclear Technology | Volume 87 | Number 1 | August 1989 | Pages 264-272
Technical Paper | TMI-2: Materials Behavior / Nuclear Safety | doi.org/10.13182/NT89-A27653
Articles are hosted by Taylor and Francis Online.
The partitioning and release of fission products from fuel materials in the Three Mile Island Unit 2 (TMI-2) reactor pressure vessel (RPV) are summarized, and the chemistry that resulted in the observed behavior is discussed. As part of the TMI-2 core examination program, samples were examined from all regions within the RPV, from leadscrews in the upper plenum to previously molten material from the lower plenum of the RPV. The results of these examinations indicate significant variations in fission product behavior that were generally consistent with the volatility and chemical behavior of the expected fission product species. Low-volatility species (e.g., 144Ce) were retained almost entirely in the fuel material matrix, whereas unoxidized species such as 125Sb were found with the metallic structural materials. Most of the high-volatility species (137Cs and 129I) were released from the previously molten fuel; however, the releases were less than expected. These fission products were retained in previously molten fuel that contained concentrations of structural materials at the grain boundaries.
