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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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Toshikazu Takeda, Hironobu Unesaki, Toshihisa Yamamoto, Katsuya Kinjo, Toshio Sanda
Nuclear Science and Engineering | Volume 101 | Number 2 | February 1989 | Pages 179-184
Technical Paper | doi.org/10.13182/NSE89-A23606
Articles are hosted by Taylor and Francis Online.
Neutron streaming in a fast breeder reactor fuel subassembly caused by the double heterogeneity of the pin structure and the wrapper tube structure is estimated by double heterogeneous modeling. The neutron streaming is decomposed into three components: the pin-cell heterogeneity, the wrapper tube heterogeneity, and the homogenized fuel/wrapper tube subassembly effect. The streaming effect is evaluated based on the Benoist diffusion coefficient. The total streaming effect caused by the double heterogeneity structure of a fuel subassembly is found to be about −0.2% Δk/kk′ for keff, which is almost twice that obtained from the conventional pin-cell model of about −0.1% Δk/kk′.
