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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).
Hideko Komoriya, Wallace F. Walters
Nuclear Science and Engineering | Volume 64 | Number 2 | October 1977 | Pages 576-581
Technical Paper | doi.org/10.13182/NSE77-A27391
Articles are hosted by Taylor and Francis Online.
The effectiveness of the energy-dependent finite element method (EDFEM) as applied to two-dimensional multigroup diffusion problems is investigated. The EDFEM couples the finite element method (FEM) formalism with the energy-dependent element size scheme. The EDFEM allows the elements to straddle material interfaces if certain conditions are satisfied; this method is especially suitable for heterogeneous reactor calculations. Comparisons of the results obtained by the EDFEM, the FEM, and the finite difference method for a ZION I pressurized water reactor model are presented. A significant reduction of the total number of unknowns involved in the problem is accomplished by using the EDFEM, which yields a reduction of the computing time by 30%.