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The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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.
A. Rastas, J. Saastamoinen
Nuclear Science and Engineering | Volume 36 | Number 3 | June 1969 | Pages 351-360
Technical Paper | doi.org/10.13182/NSE69-A18733
Articles are hosted by Taylor and Francis Online.
Neutron rethermalization has been studied, experimentally and theoretically, in a system intended to reproduce the conditions of the Kottwitz problem. Terphenyl and light water were used as the moderators at the temperatures 223 and 11°C, respectively. The energy spectrum of the angle-dependent neutron flux perpendicular to the plane discontinuity was measured in terphenyl as a function of the distance from the discontinuity by means of an extraction channel and a choppertime-of-flight analyzer. The spatial behavior of the flux-weighted average energy was determined by fitting a Maxwellian to each measured spectrum using the method of the least squares. This spatial behavior could be satisfactorily described by a simple one-exponential function for distances exceeding 3 mm (measured from the discontinuity). The least-squares fit gave a value of 11.3 mm for the relaxation length. The theoretical calculations were performed by an approximate method using the “two overlapping-groups” approximation for the energy dependence. For the angular dependence of the flux, both the Pn(n =1,3)- and the DPn(n = 1)-approximation was used. Three different scattering models were used for each moderator. Rather good agreement with the theory and the experiment was achieved as to both the form of the spectrum and the spatial behavior of the average energy.