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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.
I. Pázsit, Y. Yamane
Nuclear Science and Engineering | Volume 133 | Number 3 | November 1999 | Pages 269-281
Technical Paper | doi.org/10.13182/NSE99-A2087
Articles are hosted by Taylor and Francis Online.
The Feynman- and Rossi-alpha formulas are calculated for subcritical systems driven by a multiple emission source, i.e., one that emits several neutrons on each source emission event. The prime example of such sources is a spallation source, which will be used in future accelerator-driven subcritical systems (ADS), such as the energy amplifier. The Feynman- and Rossi-alpha formulas are calculated with backward master equations for such systems. The essence of the theory is a formula that connects the probability distribution of a cascade, induced by one single particle, with that induced by a continuous source of particles. Compact and consistent expressions are found for both the Feynman- and Rossi-alpha formulas. In agreement with earlier forward-theory-based or heuristic calculations, it is shown that the presence of the spallation source does not alter the time-dependence of the formulas, but enhances its amplitude. Hence, both methods appear to be promising to be used in future stationary ADS systems with relatively large subcriticalities.