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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.
C. O. Muehlhause
Nuclear Science and Engineering | Volume 5 | Number 4 | April 1959 | Pages 225-226
Technical Paper | doi.org/10.13182/NSE59-A25588
Articles are hosted by Taylor and Francis Online.
Values for the number of neutrons produced per thermal neutron absorbed, ηth, in the three fissile materials U233, U235, and Pu239 are reported. The measurement of these quantities was performed between the years 1951 and 1953 at the Argonne National Laboratory using the original enriched heavy water reactor, CP3', and the technique of pile oscillation. A slight revision of the data has been made on the basis of new total cross sections and f-values. The eta values at thermal energy (0.0253 ev) were found to be η23 = 2.25 ± 0.03, η25 = 2.05 ± 0.03, and η49 = 2.04 ± 0.04.