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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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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).
J. M. Neill, J. C. Young, C. A. Preskitt, G. D. Trimble, R. C. Lloyd, C. L. Brown
Nuclear Science and Engineering | Volume 46 | Number 2 | November 1971 | Pages 244-254
Technical Paper | doi.org/10.13182/NSE71-A22358
Articles are hosted by Taylor and Francis Online.
Neutron spectrum measurements covering the range thermal to 3 keV have been made by time-of-flight in three solutions of plutonium nitrate. The concentrations and 240 Pu composition of these solutions were 197.9 g/liter at 23 wt%, 193.4 g/liter at 5 wt%, and 355.0 g/liter at 5 wt%, respectively. Flux traverses and time-dependent measurements were also made in each solution. The measured spectra have been compared to theoretical calculations using the Haywood-II scattering kernel for H bound in H2O and the ENDF/B Version I cross sections for 239Pu. A good comparison is obtained for the two lowest concentrations. The disagreements for the highest concentration are ascribed to room return effects.