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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.
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.
P. Mohanakrishnan, H. C. Huria
Nuclear Science and Engineering | Volume 68 | Number 2 | November 1978 | Pages 220-226
Technical Note | doi.org/10.13182/NSE78-A27294
Articles are hosted by Taylor and Francis Online.
A theoretical analysis of the reactivities of experimentally measured uniform light-water-moderated and -reflected PuO2 in UO2 lattices and Pu(NO3)4 solutions is presented here. The mixed-oxide single-rod lattices are homogenized by the use of multigroup integral transport theory, and diffusion theory is used for the cylindrical core calculations. The cross sections are derived from the WIMS library. The homogeneous spherical Pu(NO3)4 solutions are analyzed by discrete-ordinates transport theory. Due to the small size of these assemblies, it is necessary that one-dimensional core calculations also be performed with a cross-section energy-group structure that can accurately represent neutron slowing down and thermalization at the core-reflector interface. Due to the uncertainty present in the Battelle Northwest Laboratories analyses of the mixed-oxide lattices, the agreement of our predictions for these lattices with measurement is considered to be more satisfactory. Our reactivity predictions agree generally within +0.6% of measurements for the mixed-oxide lattices and within 1% for the solution systems.
