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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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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.
P. K. Doshi, George H. Miley
Nuclear Science and Engineering | Volume 39 | Number 2 | February 1970 | Pages 182-192
Technical Paper | doi.org/10.13182/NSE70-A21198
Articles are hosted by Taylor and Francis Online.
A subcritical assembly (29 × 38 × 29 cm) built of TRIGA-type fuel elements was pulsed by coupling it with the Illinois TRIGA reactor through a graphite thermal column (2 ft square by 4 ft long). Flux measurements were made at seven locations in four different fuel loadings—9, 16, 25, and 49 fuel elements—with keff varying from ∼0.4 to 0.92. A polynomial expansion method is used to provide a continuous representation of pulse shapes. Derivatives appearing in a diffusion-theory model, evaluated using this expansion, are then used to determine the propagation velocity and the neutronic parameters. The maximum “asymptotic” velocity (removed from the boundaries) varied from ∼4 × 104 cm/sec at keff = 0.60 to 2.54 × 104 cm/sec at keff = 0.92. The theoretical model involves an expansion which, depending on the number of terms retained, bounds the experimental data. However, differences of as much as 40% in absolute values are observed and they are attributed to inadequacies in the model for this small heterogeneous assembly. Uncertainties in the neutronic parameters, as well as nonlinearities in the instrumentation, may also contribute.