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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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.
M. Segev
Nuclear Science and Engineering | Volume 56 | Number 1 | January 1975 | Pages 72-82
Technical Paper | doi.org/10.13182/NSE75-A26621
Articles are hosted by Taylor and Francis Online.
Resonance self-shielding occurs as the result of flux depressions at resonance peaks. The group self-shielding factor is defined as the ratio of the effective flux-weighted cross section to the average cross section. Given a constant background cross section, σ, as well as a temperature and an energy group, the shielding factor of an element can be approximated by simple formulas employing two- or three-group effective parameters. These are λ, η, and p—an effective base (potential scattering) cross section, an effective peak cross section, and an effective ratio of the base cross section to the average of the resonance total cross section, respectively. The use of resonance group parameters eliminates the problem of σ- interpolation. Furthermore, through a certain interpretation of these parameters, the σ- ambiguity is also cleared up. The constant background, σ, required to represent the actual interaction of the shielded resonance series with background resonance series, is a linear expression in the number densities and the λ’s of the background elements. The σ- iteration technique, currently in use, is shown to be rather inaccurate.