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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.
W. W. Graham, III, D. S. Harmer, C. E. Cohn
Nuclear Science and Engineering | Volume 38 | Number 1 | October 1969 | Pages 33-41
Technical Paper | doi.org/10.13182/NSE69-A19350
Articles are hosted by Taylor and Francis Online.
The familiar rod-drop method for determining delayed-neutron parameters has been refined with new techniques of data collection, analysis, and correction. Values for a highly enriched uranium, heavy-water reactor have been obtained which have a general applicability because they have been accurately corrected for reactor power history, post-shutdown sub-critical neutron multiplication, and finite rod-drop time. Neutron flux after shutdown by rod drop in the Georgia Tech Research Reactor was monitored for periods in excess of three days using two detectors operated in parallel. One detector used a thermal-neutron-sensitive scintillator, the other a fission chamber. Flux-decay data were fit by weighted least squares using the Variable Metric Minimization method. This method was able to fit all the data simultaneously without limit on the number of fitting parameters. The most statistically-significant fit was obtained with 13 delayed-neutron groups, one of which was attributed to background due to its negligibly small decay constant. A fitting expression was used which accurately described the data collection process in which each data point was taken as the time integral of the flux over a finite time interval. The results are compared with values which have been obtained by small irradiated uranium samples and with decay-constant values in the last reported heavy-water in-reactor determination. There are indications that delayed-neutron effectiveness is enhanced by ∼3% in this type of reactor and that the effectiveness of photoneutron groups is decreased by ∼28% because of attenuation of high-energy gamma rays.