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May 31–June 3, 2026
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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. Carew
Nuclear Science and Engineering | Volume 78 | Number 3 | July 1981 | Pages 296-297
Technical Note | doi.org/10.13182/NSE81-A20307
Articles are hosted by Taylor and Francis Online.
An equivalence relation for the effective escape cross section is derived for a lattice of annular absorber rods. The effective cross section is expressed in terms of the absorber cross section and inner and outer moderator sticking probabilities and surface escape probabilities. The lattice Dancoff and Bell factors are determined using the rational approximation for the surface escape probabilities.
