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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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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.
M. Segev, S. Taczanowski
Nuclear Science and Engineering | Volume 91 | Number 2 | October 1985 | Pages 153-161
Technical Paper | doi.org/10.13182/NSE85-A27438
Articles are hosted by Taylor and Francis Online.
The energy distribution of neutrons, from the source energy of 14 MeV down to the (n,2n) threshold, can be approximated by effective one-group cross sections for such high and medium mass number elements as lead, copper, zirconium, and iron. The same is true for 238U, when the fast fission factor ϵ is applied in a special manner to account for the added multiplication below the (n,2n) threshold. Two groups are required to obtain a reasonable description of the amplification in beryllium.
