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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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.
P. L. Reeder, R. A. Warner
Nuclear Science and Engineering | Volume 87 | Number 2 | June 1984 | Pages 181-189
Technical Note | doi.org/10.13182/NSE84-A17710
Articles are hosted by Taylor and Francis Online.
Evaluated delayed neutron emission probabilities for 74 precursors and estimated probabilities for another 174 precursors have been combined with ENDF/B-V fission yields to map out delayed neutron yields as a function of mass number, proton number, and neutron number. For all fissioning systems, more than 90% of the delayed neutron yield comes from precursors with measured Pn values. Most of the remaining yield comes from the precursors 88As, 100–103Y, and 137Sb. High priority should be given to Pn measurements for these precursors. Periodic peaks about five mass numbers apart are seen when delayed neutron yields are plotted versus mass number. This behavior is explained by the very strong enhancement of yields from odd Z precursors. Even Z precursors contribute <10% of the total delayed neutron yield. Plots of delayed neutron yields versus neutron number show dramatic decreases at the closed shell numbers 50 and 82 and smaller effects at subshell numbers 40 and 56. A procedure based on calculated and total delayed neutron yields is proposed for determining proton pairing factors in the fission yield model.