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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.
Alan Jacobs
Nuclear Science and Engineering | Volume 6 | Number 2 | August 1959 | Pages 147-151
Technical Paper | doi.org/10.13182/NSE59-A25645
Articles are hosted by Taylor and Francis Online.
A two-group albedo theory is developed which seems to be valid for the calculation of temperature coefficients of nuclear reactors characterized by the PSR. Measurements of over-all coefficient for the PSR are in qualitative agreement with results calculated by the theory. Analysis under the present theory singles out the temperature variation of the ratio of the age to the thermal neutron diffusion length of the reflector as the primary contributor to a low temperature positive coefficient effect. The advantage of representing the criticality factor, k, by the two-group albedo theory is well illustrated by the endeavor of calculating the temperature coefficient. Under normal two-group multiregion treatment the criticality factor never explicitly appears and therefore it is impossible to obtain an explicit form of the variation of k with system parameters. The dissection of the nonleakage probability in the present theory is not unique, but it does lead to easy physical interpretation.
