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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.
D. C. Leslie, A. Jonsson
Nuclear Science and Engineering | Volume 23 | Number 3 | November 1965 | Pages 272-290
Technical Paper | doi.org/10.13182/NSE23-03-272
Articles are hosted by Taylor and Francis Online.
A method of calculating first-flight collision probabilities in cluster geometry is developed. The method is analytic and approximate and is comparable in speed to codes now available for annular geometry. The proposed scheme is based on a consideration of the properties of the nonescape probability from a nonuniform body in the limits of high and low macroscopic cross sections, together with an interpolation procedure that allows one to determine the probability itself with sufficient accuracy. When calculated for combinations of different rings of fuel pins in a cluster, the resulting set of nonescape probabilities enables one to proceed to a determination of the probability of going from one ring to another. The coolant and the fuel pins are treated separately. Results of the method are compared with exact calculations on two fuel-element types of current interest. In these cases the form factor, defined as the ratio of maximum to mean flux in the cluster, is in error by at most 2%. The hyperfine structure in each ring (i.e. the ratio of the mean flux in the coolant to the mean flux in the fuel) is calculated with comparable accuracy. A one-group calculation on a 37-rod fuel element takes approximately 5 sec on an IBM-7090, so that the method is certainly usable for multigroup applications.