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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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 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.
C. K. Paulson, E. J. Hennelly
Nuclear Science and Engineering | Volume 55 | Number 1 | September 1974 | Pages 24-27
Technical Paper | doi.org/10.13182/NSE74-A23962
Articles are hosted by Taylor and Francis Online.
High-energy neutron cross sections for 237Np are needed to calculate unwanted 236Pu contaminant in 238Pu product made for heat source applications in space and medical projects. Recent improved determination of 236Pu formation by 237Np(n, 2n) reactions completes the information needed to calculate 236Pu/238Pu ratios over a wide range of 237Np irradiation environments, from D2O reflectors to pressurized-water-reactor fuel. The 237Np(n, 2n) 236&Np cross section is 63 ± 6 mb, averaged over the 235U fission spectrum >6.8 MeV; this result is consistent with the cross section calculated by Pearlstein.
