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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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.
Pierre Benoist
Nuclear Science and Engineering | Volume 30 | Number 1 | October 1967 | Pages 85-94
Technical Paper | doi.org/10.13182/NSE67-A17245
Articles are hosted by Taylor and Francis Online.
A general expression allowing the calculation of the influence on cell factors of an anisotropic component of the scattering law in a given medium is established in the framework of the integral transport theory. This expression is applied to the calculations of the thermal utilization, fast fission factor, and diffusion coefficients. In the case of the thermal utilization, the effect of the anisotropic scattering in the moderator can be taken into account by a rigorous correction whatever the cell; this correction coincides with the classical transport correction only for widely spaced lattices, and still with some restrictions; for closely packed lattices the transport correction has no theoretical justification, and seriously underestimates the effect. In the fuel, the transport correction is no more theoretically justified, although it leads to good results for rather large rods; a very simple formula is established from the general expression, allowing the calculation of the correction to f, without using the transport cross section. This formula leads, for all the rod diameters considered, to results in very good agreement with referenced values obtained by the S8 method. An analogous formula for the fast-fission factor is established.