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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.
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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.
Bertram Wolfe, David L. Fischer
Nuclear Science and Engineering | Volume 4 | Number 6 | December 1958 | Pages 785-793
doi.org/10.13182/NSE58-A15498
Articles are hosted by Taylor and Francis Online.
An exact expression for the reactivity effect of a control element placed in a reactor is derived within the limitation of validity of multigroup diffusion theory. The evaluation of the expression requires a knowledge of the flux distributions in the reactor with and without the element (s) inserted. Since the reactivity effect is stated in terms of the flux distribution in the perturbed and unperturbed reactors, one can calculate the effect of a control element if a good estimate for the form of the perturbed flux is made. A first-order perturbation calculation for thermally black control elements is presented. The perturbation calculation assumes that the fast flux is unaffected by the presence of the control element. The results are valid for a reactor in which the neutron age is large compared to the square of the thermal diffusion length and for a control element which is small compared to both the size of the reactor and the square root of the age.