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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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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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.
Yukio Ishiguro
Nuclear Science and Engineering | Volume 51 | Number 4 | August 1973 | Pages 512-514
Technical Note | doi.org/10.13182/NSE73-A23281
Articles are hosted by Taylor and Francis Online.
The intermediate resonance approximation of resonance absorption is applied to a heterogeneous fast reactor assembly to see how each resonance of 238U deviates from the narrow resonance approximation. The resonance integral is calculated for the 50 resonances of 238 U in ENDF/B-II below 1.9 keV. The averaged deviation of these resonances from the narrow resonance extreme was found to be ∼4%. It is concluded that the effective group cross sections in heterogeneous fast systems can be estimated reasonably well by the narrow resonance approximation, even though this approximation tends to underestimate the resonance integrals noticeably for a handful of resonances with extremely large neutron widths.
