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Conference Spotlight
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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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).
D. C. Hunt, Robert E. Rothe
Nuclear Science and Engineering | Volume 46 | Number 1 | October 1971 | Pages 76-87
Technical Paper | doi.org/10.13182/NSE71-A22337
Articles are hosted by Taylor and Francis Online.
The results of criticality measurements on enriched (93.16% 235U) uranium metal spheres symmetrically immersed in enriched (93.18% 235U) uranyl nitrate solution cylinders are reported. The solution cylinders are 26.5, 38.4, and 51.1 cm in diameter with heights ranging from 16 to 70 cm. Solution concentrations, expressed in grams of uranium per liter, are 11.47, 12.55, 13.12, 21.25, 24.20, 24.72, 103.0, and 104.8. Twenty-seven critical systems are identified. The experimental critical parameters of each system are compared with computed values obtained by transport (DTF) and Monte Carlo (KENO) methods. Results from neither, method exhibit a systematic difference from experimental values; the average difference in the critical radius is 2.5% for DTF and 2.0% for KENO. The effects of experimental perturbations are determined experimentally and calculationally.
