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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 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
Amazon provides update on its Washington project with X-energy
A year ago this month, Amazon led a $500 million investment in X-energy, alongside Citadel founder Ken Griffin, the University of Michigan, and other investors. In addition to that financing, Amazon pledged to support the development of an initial four-unit, 320-MW project with Energy Northwest in Washington state.
T. H. Springer, S. G. Carpenter and R. J. Tuttle
Nuclear Science and Engineering | Volume 20 | Number 3 | November 1964 | Pages 272-280
Technical Paper | doi.org/10.13182/NSE64-A19569
Articles are hosted by Taylor and Francis Online.
A negative Doppler effect has been observed in measurements on a metallic uranium sample (enriched to 93% in U235) placed in a typical fast-reactor spectrum which has a median fission energy of 195 keV. The plausibility of the negative sign is supported on theoretical grounds, although with the use of standard analytical techniques and the limited number of resonance parameters at present available, it cannot be calculated for this spectrum. The value for was found to be -5.65 × 10-6/°C. New measurements on U238 have been made, and the data on Th232, previously published, have been extended to 930 C. The agreement between analytical and experimental values for the latter two materials is good.
