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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Fabrication milestone for INL’s MARVEL microreactor
A team from Idaho National Laboratory and the Department of Energy’s Office of Nuclear Energy (DOE-NE) recently visited Carolina Fabricators Inc. (CFI), in West Columbia, S.C., to launch the fabrication process for the primary coolant system of the MARVEL microreactor. Battelle Energy Alliance (BEA), which manages INL, awarded the CFI contract in January.
John C. Lee, Sin Tao Hsue
Nuclear Technology | Volume 76 | Number 2 | February 1987 | Pages 203-208
Technical Paper | Fuel Cycle | doi.org/10.13182/NT87-A33874
Articles are hosted by Taylor and Francis Online.
Based on a simplified solution of the balance equations for concentration of uranium and plutonium isotopes and a set of two-group microscopic cross sections, isotopic ratios, 235U/U, Pu/U, and 239Pu/235U, are calculated as a function of fuel burnup for pressurized water reactor spent fuel. The two-group cross sections for 235U, 238U, 239Pu, and water are collapsed into equivalent thermal-group constants, with the fast-to-thermal flux ratio obtained through a two-group criticality consideration. For this purpose, parasitic neutron captures are represented through a simple semiempirical relationship. The calculational model, incorporated as the BURN code, yields isotopic ratios that compare favorably with three major data sets from the ISTLIB data bank.
