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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).
K. Ganguly, A. Sengupta
Nuclear Science and Engineering | Volume 74 | Number 1 | April 1980 | Pages 1-12
Technical Paper | doi.org/10.13182/NSE80-A18940
Articles are hosted by Taylor and Francis Online.
In this paper, transport theory methods have been used to obtain a modified form of the PN approximation. This modification involves use of the exact asymptotic roots instead of the PN roots, resulting in a corresponding change in the Marshak free surface boundary conditions. Various numerical examples of this transport theoretic PN approximation have been given.
