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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
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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
New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Jay E. Boudreau, R. C. Erdmann
Nuclear Science and Engineering | Volume 51 | Number 2 | June 1973 | Pages 206-222
Technical Paper | doi.org/10.13182/NSE73-A26595
Articles are hosted by Taylor and Francis Online.
Secondary criticality resulting from massive core rearrangement is discussed where the material dynamics results from either mild or strong initial excursions. Diffusion theory is used to study the effect of moving boundaries on the flux, and to study the effect of internal fuel rearrangement on keff. Numerical transport methods are used to make accurate determinations of keff for complicated fuel configurations arising from disassembly calculations. It is concluded that secondary criticality may occur from fuel rearrangement, but that it is unlikely in most cases. Variations in core height/diameter ratio, zonal enrichment, and overall size can change the tendency for autocatalysis significantly.
