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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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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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Latest News
White House taps Douglas Weaver for NRC role
The Trump White House has nominated seasoned nuclear regulatory expert Douglas Weaver for a commissioner seat on the Nuclear Regulatory Commission. If confirmed, Weaver would fill the seat vacated by NRC commissioner Annie Caputo, who resigned in July.
Weaver’s nomination was sent earlier today to the Senate Environment and Public Works Committee. If confirmed, he would finish the remainder of Caputo’s term, which expires June 30, 2026.
Wayne K. Lehto
Nuclear Science and Engineering | Volume 39 | Number 3 | March 1970 | Pages 361-367
Technical Paper | doi.org/10.13182/NSE70-A19996
Articles are hosted by Taylor and Francis Online.
The fission cross-section ratios of 239Pu to 235U and 233U to 235U have been measured from 0.24 to 24 keV using parallel-plate, back-to-back fission detectors and a slowing down lead spectrometer as a neutron source. Relative fission rates obtained from the experiments were converted to true fission cross-section ratios by detector intercalibration in a thermal-neutron flux. In the case of the Pu/U ratio, these results extend the data to below several keV where measurements have not previously been made and the 233U/235U results verify previous measurements made in this energy region.
