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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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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.
Henry A. Sandmeier
Nuclear Science and Engineering | Volume 9 | Number 2 | February 1961 | Pages 260-270
doi.org/10.13182/NSE61-A15608
Articles are hosted by Taylor and Francis Online.
To test reactor fuel elements for their content of fissionable material and poison, it is desirable to have an assembly which has maximum sensitivity to a perturbation of fissionable absorber in the axial center line of the reactor. For normal sizes of thermal power reactor fuel elements, a graphite-moderated reactor is a suitable choice. The change in reactivity measured is the difference between the effect of changes in the fission and absorption parameters. For a bare core and uniform fuel distribution, maximum sensitivity to a fission-parameter-perturbation is obtained for a reactor which has a minimum critical mass. Maximum sensitivity to an absorber-parameter-perturbation is obtained for a reactor which has a minimum amount of total absorptions. Both the fission and absorption sensitivity reach a maximum when the critical mass is minimum. For a reflected core and uniform fuel distribution, the sensitivity to a fissionable absorber can be increased 22% over the bare core sensitivity. By introducing an internal and external reflector, the sensitivity to a fissionable absorber can be increased 30% over the externally reflected core and 56% over the bare core. For nonuniform fuel distribution, an expression is derived relating the effect of a perturbation in fission and absorption to reactivity. The problem of finding a fuel distribution ψ(r) to maximize this expression is analytically formulated. A parameter study was made for the same reactors as for the uniform fuel distribution cases. This was done by shifting more fuel towards the center or towards the edge of the core. No gain in fissionable absorber sensitivity was observed for either the bare or the externally reflected cores. However, the internally and externally reflected core showed a 10% increase in fissionable absorber sensitivity when more fuel was shifted towards the center.