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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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).
John F. Conant, Philip F. Palmedo
Nuclear Science and Engineering | Volume 44 | Number 2 | May 1971 | Pages 173-179
Technical Paper | doi.org/10.13182/NSE71-A19665
Articles are hosted by Taylor and Francis Online.
The delayed-neutron fractions for thermal fission of 235U, 239Pu, and 233U were measured and found to be The technique used to perform the measurements was intrinsically simple and involved making only relative measurements. The basic approach was to compare the neutron production rate of a thin fissile sample in a thermal-neutron beam with the delayed-neutron production after an abrupt termination of the beam. The work was greatly enhanced through the use of a modified long counter that was developed at the Los Alamos Scientific Laboratory. The results of this work are in essential agreement with the presently accepted values, which were reported in 1957 and were measured by using a different technique than that used here.
