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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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.
R. G. Fluharty, F. B. Simpson, and G. J. Russell, J. H. Menzel
Nuclear Science and Engineering | Volume 35 | Number 1 | January 1969 | Pages 45-69
Technical Paper | doi.org/10.13182/NSE69-A21113
Articles are hosted by Taylor and Francis Online.
Pulsed reactors are being investigated for the purpose of producing high-intensity pulsed-neutron beams for research. Leakage-emission-time-distribution measurements as a function of neutron energy have been carried out using the Resselaer Polytechnic Institute (RPI) electron linear accelerator in conjunction with a disk chopper and neutron diffraction spectrometer. Data were obtained simultaneously with the chopper and crystal spectrometer by looking at opposite sides of the moderator. This experiment was designed to investigate the importance of different variables in determining the pulse characteristics of moderators. The eventual objective is to optimize the maximum thermal-neutron intensity and minimum pulse width from pulsed-fission-neutron sources. Neutron time and energy distributions were measured for light water, polyethylene, Lucite (a metacrylate plastic), powdered zirconium hydride, and ammonia. The water, polyethylene, and zirconium-hydride samples were measured at room temperature and all the materials except water were also measured at liquid-nitrogen temperature. The effects on pulse characteristics of homogeneously poisoning light water samples were studied, as well as the effects of heterogeneously poisoning polyethylene. The effect of varying the thickness of the moderator was also investigated. Pulse widths at half-maximum of 11 µsec at 0.05096 eV and 24 µ sec at 0.01274 eV were observed for solid ammonia and heterogeneously poisoned polyethylene samples. For neutron energies between 0.08 and 0.01274 eV, solid ammonia gave the best observed figure of merit, peak intensity/ (FWHM)2. The data show that neutron pulse characteristics from a moderator can be altered significantly by varying the material and its temperature, as well as by adding poison and optimizing the geometry. Time distributions were observed in the energy region of 0.012 to 0.63 eV. The time resolution, in this energy region, for the diffraction spectrometer ranged from 2.8 to 10.8 µ sec compared with 7.6 µ sec for the chopper.