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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.
Donald S. Rampolla
Nuclear Science and Engineering | Volume 31 | Number 3 | March 1968 | Pages 396-414
Technical Paper | doi.org/10.13182/NSE68-A17584
Articles are hosted by Taylor and Francis Online.
In the design of nuclear reactors it is frequently necessary to adjust the parameters appearing in the equations describing neutron transport, e.g., the macroscopic absorption cross section in the diffusion equation, in order to force region reaction rates to agree with results of more exact calculations or experiment. Given a multiregion cell problem with a specified absorption rate in each region it is proved that there exists, for any neutron transport equation that has a solution that is everywhere positive, a non-unique set of region absorption cross sections which yield the specified absorption rates; however, if the cross section is fixed in one region, the set is, in a specially defined sense, unique. Two systematic iterative methods for obtaining such sets of region cross sections are presented; one of these methods has been incorporated into a computer program.
