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Radiation Protection & Shielding
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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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. F. Henry
Nuclear Science and Engineering | Volume 27 | Number 3 | March 1967 | Pages 493-510
Technical Paper | doi.org/10.13182/NSE86-A17615
Articles are hosted by Taylor and Francis Online.
The equations and boundary conditions that constitute the P1 approximation to the space-time-energy transport equation and its adjoint can be obtained from a variational expression that admits trial functions discontinuous in space and energy. This expression can then be used to derive all the standard forms of the few-group diffusion equations—equations using flux averaged constants, over-lapping group equations, parallel group equations—as well as many more hitherto unexamined. Such a procedure is carried out in the present paper. All the standard few-group results, as well as formally exact few-group equations and multigroup equations, are shown to be special cases of a single general form derived from the variational expression. Internal boundary conditions are obtained automatically, and it is shown that in some cases discontinuities in fluxes and currents ought to be imposed across internal boundaries.