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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.
Jin Beak Park, Yong Soo Hwang, Chul Hyung Kang
Nuclear Science and Engineering | Volume 142 | Number 2 | October 2002 | Pages 165-176
Technical Paper | doi.org/10.13182/NSE02-A2297
Articles are hosted by Taylor and Francis Online.
Matrix diffusion into a rock matrix has been regarded to retard radionuclide migration in a fracture. Recent field findings on a fractured system indicate that only a small portion of the rock in a fractured porous medium contributes to holding a radionuclide by matrix diffusion. To understand this effect, radionuclide migration in a fracture and diffusion from a finite rock matrix to a fracture are discussed with limited matrix diffusion under solubility-limited boundary conditions of a target radionuclide for the band-type release. Numerical inversion of the Laplace transform method is applied to estimate concentrations in a fracture and a finite rock matrix and fluxes at the fracture surface. Matrix diffusion into a finite rock matrix shows enhanced radionuclide migration and a higher concentration profile in a fracture. Diffusive flux from a finite rock matrix into a fracture after the end of leaching time shows higher peak values than flux from an infinite rock matrix because of (a) higher saturation of a radionuclide in a finite rock matrix and (b) increase of a radionuclide concentration in a fracture. Therefore, it is more realistic and conservative to apply the finite matrix diffusion for the overall assessment in a potential repository embedded in a fractured porous medium.