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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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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. Saphier, D. Ilberg, S. Shalev, S. Yiftah
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 660-694
Technical Paper | doi.org/10.13182/NSE77-A15209
Articles are hosted by Taylor and Francis Online.
Delayed neutron emission spectra from thermal-neutron fission of 233U, 235U, 239Pu, and 241Pu, from fast-neutron fission of 232Th, 235U, 238U, and 239Pu and from high-energy neutron (14.7-MeV) fission of 235U and 238U, for six groups of delayed neutrons are evaluated. The evaluation is based on recent measurements of delayed neutron spectra from 20 fission product isotopes. The data are presented in graphic form and are compared to directly measured equilibrium spectra whenever available. Tables with a convenient 54-energy-group structure are provided to facilitate their use in reactor calculations. The results of a limited number of two-dimensional, multigroup, transient calculations for the Clinch River Breeder Reactor core, using the newly evaluated spectra, are compared with calculations using some older spectra. The importance of the inclusion of these data in reactor dynamic calculations is evaluated.
