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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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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August 2024
Latest News
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.
S. Yip, P. F. Zweifel
Nuclear Science and Engineering | Volume 10 | Number 4 | August 1961 | Pages 362-366
doi.org/10.13182/NSE61-A15379
Articles are hosted by Taylor and Francis Online.
Explicit formulas are given one-velocity escape probabilities from absorbing and (isotropic) scattering slabs in vacuo as calculated by the methods of asymptotic reactor theory. The results are compared with exact numerical calculations, diffusion theory, and a variational principal. Even for slabs as thin as two mean free paths, the asymptotic calculations are found to be highly accurate. By comparing the asymptotic methods with some multiple-scattering calculations for infinite cylinders, an extrapolated boundary has been defined for the cylinder, and in this fashion explicit formulas have been obtained for the escape probabilities from finite cylinders.