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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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.
A. J. H. Goddard, P. W. Johnson
Nuclear Science and Engineering | Volume 37 | Number 1 | July 1969 | Pages 127-136
Technical Paper | doi.org/10.13182/NSE69-A20904
Articles are hosted by Taylor and Francis Online.
Thermal-neutron diffusion lengths have been measured with an accuracy of typically ½% in aqueous absorbing solution contained in a tank adjacent to a reactor thermal column. Both pure water and boric acid solutions were used at 22.3 and 65°C, and solutions of cadmium and gadolinium salts at the lower temperature. Ten concentrations of each absorber were used. Two of the measured diffusion lengths for cadmium yield space eigenvalues which violate the (ΣT)min limit of Corngold. Slight diffusion cooling occurs in cadmium solutions in contrast to marked heating effects in boron and gadolinium solutions. Theoretical predictions of diffusion lengths have been obtained by a B2 solution of the transport equation. Four scattering models were used: the Nelkin model, Haywood model, and two further models consisting of modifications to each of these. The modifications highlight particular parts of the hydrogen-atom generalized frequency distribution. A Laguerre polynomial expansion technique is investigated but found to be unsuitable for the analysis of non-1/v poison data.