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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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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.
James A. Davis
Nuclear Science and Engineering | Volume 25 | Number 2 | June 1966 | Pages 189-197
Technical Paper | doi.org/10.13182/NSE66-A17736
Articles are hosted by Taylor and Francis Online.
Approximate vacuum boundary conditions for a PN approximation are obtained by variational methods. Two stationary principles are proposed, one having what we shall call “odd” Marshak conditions as its natural boundary conditions, and the other having “even” Marshak conditions as its natural boundary conditions. The principles are valid for arbitrary geometry. The odd Marshak conditions are seen to be suitable for an odd-order PN approximation and the even Marshak conditions for an even-order PN approximation. The odd Marshak conditions are precisely the conditions obtained by Vladimirov from an extremum principle in which certain restrictions are imposed on the source and scattering. The present treatment contains no such restrictions.
