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Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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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.
Rajesh Mohan, Feroz Ahmed, L. S. Kothari
Nuclear Science and Engineering | Volume 81 | Number 4 | August 1982 | Pages 532-539
Technical Paper | doi.org/10.13182/NSE82-A21443
Articles are hosted by Taylor and Francis Online.
The multigroup diffusion equation is solved for the pulsed problem and the time-dependent energy spectra are obtained using the eigenfunction expansion method. It is shown that complete spectral equilibrium can be obtained beyond 2000 ns in a 40-cm cube (B2 ∼ 0.015 cm-2) of natural uranium. This time is found to increase with increasing assembly size. The earlier exponential decays observed in a pulsed uranium system are traced to the establishment of the pseudo-equilibrium condition due to the trapping of neutrons in certain energy groups. It is shown that such a pseudo-decay corresponds to the establishment of the first higher mode of decay and the time range in which it is established is a function of B2.
