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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
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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August 2024
Latest News
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.
Ashok K. Agrawal, Sidney Yip
Nuclear Science and Engineering | Volume 37 | Number 3 | September 1969 | Pages 368-379
Technical Paper | doi.org/10.13182/NSE69-A19113
Articles are hosted by Taylor and Francis Online.
The incoherent neutron scattering cross section of molecular liquids is evaluated using correlation function descriptions of molecular translations and rotations. The calculation is based on the Gaussian approximation for the intermediate scattering function, and the analysis is specifically directed at the energy region of thermal and cold neutrons. Physical models are used to calculate the translational and rotational effects in the mean-square displacement (width) function, or equivalently, the generalized frequency distribution, and it is assumed that translation-rotation couplings can be ignored. The description of center-of-mass motions properly includes the short-time vibrations as well as the long-time diffusion. Different rotational models are discussed, and a simple expression is suggested which relates the rotational correlation function to the Fourier transform of a near infrared vibrational absorption band. Explicit calculations are carried out for liquid methane, and the results are in quite satisfactory agreement with both thermal- and cold-neutron measurements. The results also indicate that inelastic scattering effects are mostly due to rotational motions. Total cross sections are computed and found to agree with experiment (to within 3%) in the range 1-50 × 10−3 eV.