ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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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.
Keisho Shirakata, Toshio Sanda, Fumiaki Nakashima
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 187-198
Technical Paper | doi.org/10.13182/NSE99-A2027
Articles are hosted by Taylor and Francis Online.
Space-dependent nuclear characteristics, measured by critical experiments on large-size fast breeder reactor (FBR) cores, were reviewed and interpreted. It was observed that radial neutron flux distributions were significantly distorted by perturbations, control rod reactivity interaction effects were large, and the point kinetics was not valid. These physical behaviors are enhanced as the spatial neutronic decoupling increases. To obtain stable and benign nuclear characteristics and to make the kinetics as close to the point kinetics as possible, it is necessary to reduce the spatial decoupling. This is an important issue that must be taken into account in the nuclear design for large FBR cores.A new nuclear core design method for large FBR cores is proposed in which neutronic stability is considered at the same time as performance and safety for the optimization of core design. The neutronic stability is improved by reducing the spatial decoupling and by taking into account the spatial higher harmonics.