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Division Spotlight
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
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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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.
Masahide Imasaki and Torao Yanaru
Nuclear Science and Engineering | Volume 33 | Number 1 | July 1968 | Pages 93-105
Technical Paper | doi.org/10.13182/NSE68-A20921
Articles are hosted by Taylor and Francis Online.
The stability of flux-shaped spatial modes is studied in a Calder Hall type reactor in three dimensions using the homogeneous boundary condition of the reactivity with the following three results: 1) the modal interaction due to coolant flow is also a second-order term in the three-dimensional modal analysis and can be ignored as the first approximation; 2) the Nyquist criterion should be applied to the expression containing the involved transcendental function in the transfer function of the thermal system; and 3) the simple thermal model, which treats only the fuel, moderator, and coolant, is adequate to judge the stability of the mode. The effects of flattening the radius on the threshold value of the moderator reactivity temperature coefficient and on the period of the sustained oscillation have been studied by this method as a function of the eigenvalue, and it has been shown that: 1) the modes with the same order in axial and radial direction form a group; and 2) the modes with the second order in axial direction are more stable than the modes with the first order in axial direction.