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The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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.
J. D. Spencer, T. G. Williamson
Nuclear Science and Engineering | Volume 27 | Number 3 | March 1967 | Pages 568-572
Technical Paper | doi.org/10.13182/NSE86-A17623
Articles are hosted by Taylor and Francis Online.
The age of fission neutrons was measured to the indium resonance energy for light water and three metal-to-water volume ratios (1/4, 1/2, 2/3) in aluminum- water mixtures. A large plane highly enriched 235U fission plate provided the source of neutrons. Aluminum plates (0.127 × 122 × 122 cm) oriented parallel to the source plane were used for the metal. Indium foil activities were taken in planes parallel to the source and integrated over these planes to obtain the equivalent activities that would result from an infinite source. From these data, the ages for the four cases were: M/W = 0, (26.24 ± 0.33 cm2); M/W = 1/4, (32.28 ± 0.50 cm2); M/W = 1/2, (39.96 ± 0.50 cm2); M/W = 2/3, (44.88 ± 0.59 cm2). To investigate heterogeneous effects, the plates were lumped to simulate 0.635-cm-thick plates and the measurements repeated for the 2/3 metal-to-water ratio. The measured age was 44.50 ± 0.49 cm2, indicating no lumping effect in this measurement. The data for the pure water measurement were also analyzed by applying geometric corrections for the finite size of the source plate. This resulted in a measured age of 27.82 ± 0.66 cm2, which agrees with previous measurements utilizing this method of data analysis.