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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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).
Guillermo Velarde, Carolina Ahnert, José M. Aragonés
Nuclear Science and Engineering | Volume 66 | Number 3 | June 1978 | Pages 284-294
Technical Paper | doi.org/10.13182/NSE78-A27213
Articles are hosted by Taylor and Francis Online.
The time-dependent Boltzmann equation for neutron transport is transformed into eigenvalue equations in k, λ, γ, and α, whose general properties are stated as hypotheses. Numerical solutions are obtained with the discrete-ordinates code DTF, where a direct λ eigenvalue calculation has been added. Eigenvalues and eigenfunctions are analyzed for idealized fast and thermal systems in both bare and reflected configurations. The differences found in these idealized cases provide some useful bases for estimating the behavior of the different eigenvalue solutions in specific applications.