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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
C. A. Bisselle, John A. Wethington, Jr.
Nuclear Technology | Volume 5 | Number 6 | December 1968 | Pages 445-455
Technical Paper and Note | doi.org/10.13182/NT68-A27970
Articles are hosted by Taylor and Francis Online.
A technique was developed for determining the previously unknown thermal-neutron diffusion parameters, ∑a and D, of a small amount of a moderating material, perfluorodimethylcyclohexane, C8F16. A two-region cylindrical system consisting of C8F16 in the core region and water in the reflector region was pulsed with neutrons to obtain the decay constants for several heights of the system. By comparing these results with those obtained from a similar water-graphite experiment and by utilizing one-group, two-region diffusion theory, it was possible to obtain the desired parameters for the fluoro-carbon, i.e., D(C8F16) = 1.02 cm, ∑a(C8F16) = 90 × 10−5/cm, and L(C8F16) = 33.6 cm. This technique offers a convenient method for determining the neutron diffusion parameters of small samples of rare materials.