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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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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).”
David Maxwell Barton
Nuclear Science and Engineering | Volume 33 | Number 1 | July 1968 | Pages 51-55
Technical Paper | doi.org/10.13182/NSE68-A20917
Articles are hosted by Taylor and Francis Online.
Central reactivity contributions of gram-sized samples of 244Cm, 239Pu, and 235U have been obtained in a fast critical assembly of bare 239Pu in a spherical geometry. Resulting values are: 244Cm = (1276 ± 5%) cents/g at.; 239Pu = (1393 ± 3%) cents/g at.; 235U = (701 ± 2%) cents/g at. From these data, the critical mass of a bare sphere of 244Cm is estimated to be (27.7 ± 2.5) kg at a density of 13.5 g/cm3.
