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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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.
W. L. Whittemore
Nuclear Science and Engineering | Volume 18 | Number 2 | February 1964 | Pages 182-188
Technical Paper | doi.org/10.13182/NSE64-A18317
Articles are hosted by Taylor and Francis Online.
The General Atomic neutron-velocity selector has been used at the electron linear accelerator to study the inelastic scattering by liquid methane and liquid parahydrogen of monoenergetic neutrons with incident energies in the range 0.009 to 0.17 eV. The energy dependence of the total cross sections and the neutron spectra produced by specimens of these materials have also been measured. The inelastic scattering of slow neutrons (< 0.010 eV) at 90° by liquid parahydrogen appears to be smaller than expected on the basis of the measured total cross section and the angular dependence calculated by Sarma. Perhaps this is related to the fact that the total cross section is larger than for freely rotating molecules, indicating the possible existence of some hindrance to molecular motion. The slowing-down power, σnE0/E, a quantitative measure of the neutron-moderating ability, is evaluated from the measured inelastic neutron-scattering data and compared for various neutron energies for the two liquids. A consideration of the various data leads to the conclusion (1) that solid methane is better than liquid parahydrogen for production of very “cold” neutrons (E0 < 0.007 eV), and (2) that parahydrogen is superior to liquid methane for production of cold neutrons with E0 < 0.005 eV.