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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Eric P. Loewen, Kevan D. Weaver, Judith K. Hohorst
Nuclear Technology | Volume 137 | Number 2 | February 2002 | Pages 97-110
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT02-A3260
Articles are hosted by Taylor and Francis Online.
Recent investigations into the performance and economics of mixed thoria-urania fuel cycles demonstrate potential advantages at high burnup. Initial neutronic and fuel behavior calculations for several ThO2-UO2 mixtures being considered for use in commercial nuclear power plants are described.The Monte Carlo N-Particle -Origen2 Coupled Utility Program (MOCUP) was used to analyze the reactivity characteristics and isotopic concentrations of unit fuel pins/cells and lattice/assembly models as a function of burnup and reactivity. Neutronic results for a three-batch 6-yr cycle for each of three proposed ThO2-UO2 mixtures with the UO2 enriched to 19.5% 235U are presented. Neutronic results show that fuels fabricated from ThO2-UO2 mixtures can reach an average discharge burnup of up to 70 MWd/kgHM, which will increase the time between refueling and decrease the production of weapons-grade plutonium by a factor of 3 as compared to all-urania fuel.A version of FRAPCON-3, modified to handle pure thoria and ThO2-UO2 mixtures, was used for the fuel performance and behavior calculations. The new version called FRAPCON-3Th includes the updated material property models for thermal conductivity, specific heat capacity, emissivity, thermal expansion, modulus of elasticity, and melting temperature to predict fuel behavior for pure ThO2 or ThO2/UO2 mixed fuel. For a concentration of 75% ThO2/25% UO2, initial fuel performance parameters (peak centerline temperature, gap conductance, thermal expansion, etc.) predicted operating conditions are better than those of current UO2 fuel. A ThO2-ThO2/UO2 thermal conductivity model is still in the development stage. For all fuel calculations, an interim model that interpolates between the Belle and Berman predicted thermal conductivity using a correction factor for radiant heat transport and the MATPRO-predicted thermal conductivity for UO2 was applied.
