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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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
Perpetual Atomics, QSA Global produce Am fuel for nuclear space power
U.K.-based Perpetual Atomics and U.S.-based QSA Global claim to have achieved a major step forward in processing americium dioxide to fuel radioisotope power systems used in space missions. Using an industrially scalable process, the companies said they have turned americium into stable, large-scale ceramic pellets that can be directly integrated into sealed sources for radioisotope power systems, including radioisotope heater units (RHUs) and radioisotope thermoelectric generators (RTGs).
S. G. Carpenter, J. M. Gasidlo, J. M. Stevenson
Nuclear Science and Engineering | Volume 49 | Number 2 | October 1972 | Pages 236-239
Technical Note | doi.org/10.13182/NSE72-2
Articles are hosted by Taylor and Francis Online.
The effective delayed-neutron fractions of 235U and 239Pu have been determined for two fast critical assemblies from measurements of the absolute fission rate and the apparent reactivity worths of a calibrated 252Cf neutron source. The experimental values of βeff for the two fissile isotopes, 0.0078 to 0.00233, respectively, are in reasonable agreement with calculations. The results do not explain the 30% discrepancy in measured and calculated reactivity values in fast critical experiments.
