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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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).
Ehud Greenspan
Nuclear Science and Engineering | Volume 56 | Number 1 | January 1975 | Pages 103-106
Technical Note | doi.org/10.13182/NSE75-A26628
Articles are hosted by Taylor and Francis Online.
A new definition of reactivity, the source-multiplication reactivity, is presented. The physical meaning of the source-multiplication reactivity is discussed, and its relationship with the static and other definitions of reactivity is investigated. The definition of correction factors required for inferring different reactivities from source-multiplication measurements is also discussed.
