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Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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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.
G. S. Gangwani, S. P. Tewari, L. S. Kothari
Nuclear Science and Engineering | Volume 50 | Number 4 | April 1973 | Pages 337-344
Technical Paper | doi.org/10.13182/NSE73-A26568
Articles are hosted by Taylor and Francis Online.
A theoretical study of the pulsed neutron problem and of steady-state neutron spectra has been made in mixtures of H2O and D2O in the temperature range 253 to 4°K. Mixtures with D2O content of 0, 5, 10, 15, and 20 wt% have been considered. For the pulsed neutron problem the multigroup Boltzmann equation in the diffusion approximation has been diagonalized to obtain asymptotic and transient spectra in assemblies with buckling values ranging from 0 to 0.6 cm-2 at 253, 77, and 21°K. The calculated values of the fundamental mode decay constant in various assemblies of ice at 253°K containing 20% D2O are found to agree very well with the experimental values reported by Salaita.For the steady-state problem, the multigroup inhomogeneous Boltzmann equation in the diffusion approximation has been solved by the matrix inversion method for different mixtures at 253, 77, 21, and 4°K. We show that there is an enhancement of cold neutron flux as the D2O content in ice is gradually increased. As in the case of H2O ice, we find that the mean energy of the neutron distribution goes on decreasing with decrease in ice temperature only as long as the temperature is above about 20°K. No further reduction in the mean energy of the neutron distribution is obtained when the temperature of the mixture is reduced below 21°K. It is shown that at 21°K, ice containing about 10 to 20% D2O is a better cold neutron source than pure H2O ice.
