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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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 coolants, new fuels: A new generation of university reactors
Here’s an easy way to make aging U.S. power reactors look relatively youthful: Compare them (average age: 43) with the nation’s university research reactors. The 25 operating today have been licensed for an average of about 58 years.
S. T. Perkins
Nuclear Science and Engineering | Volume 39 | Number 1 | January 1970 | Pages 25-31
Technical Paper | doi.org/10.13182/NSE70-A21168
Articles are hosted by Taylor and Francis Online.
Doppler broadening of neutron cross sections is described under the combined influence of temperature and boundary motion. The effective cross section is explicitly presented for the two cases of a constant speed, isotropic boundary motion (which is identical to the condition of an isotropic neutron flux), and also a constant speed, monodirectional boundary motion. The functional relations interconnecting the effective cross section at different temperatures and boundary motion velocities are pointed out. The results of numerical calculations are also presented.
