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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
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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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.
John E. Suich, Henry C. Honeck
Nuclear Science and Engineering | Volume 20 | Number 1 | September 1964 | Pages 93-110
Technical Paper | doi.org/10.13182/NSE64-A19279
Articles are hosted by Taylor and Francis Online.
A method is developed for calculating the temperature coefficient of ηf for heterogeneous reactor lattice cells on a fairly rigorous basis, using only microscopic material constants as input data. The method is based on the integral transport equation, and involves flux and adjoint weighting the temperatures derivatives of the kernels of the integral operators. Temperature coefficients are obtained for a localized temperature increase, as well as for a uniform increase in cell temperature. The coefficients are separated, on physical grounds, into ‘spectrum’ and ‘transport’ effects. The numerical accuracy of the method is found to be limited, at the present time, by the uncertainties in fuel reaction cross sections. The method is used in a brief survey of temperature effects in natural-uranium/graphite lattices. The transport temperature coefficients are shown to yield the dependence of the thermal multiplication factor on a velocity-averaged diffusion coefficient. The spectrum temperature coefficients give the dependence of the thermal multiplication factor on average neutron velocity and disadvantage factor. Non-diffusion effects are noticed when the region near the fuel is heated. The results of the method are compared with published experimental results for natural-uranium/graphite lattices. Good agreement between theory and experiment is obtained. The influence of reactor operating conditions on temperature coefficients is reproduced by the theory.