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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).
E. Neymotin
Nuclear Science and Engineering | Volume 75 | Number 2 | August 1980 | Pages 133-139
Technical Paper | doi.org/10.13182/NSE80-A21302
Articles are hosted by Taylor and Francis Online.
An approximate form of the transport equation is used to investigate stationary and time-dependent neutron slowing down and propagation in the field of gravity. The approximation is based on the expansion of the δ function of the transfer function in a power series of a small parameter s, the ratio of the neutron to atom masses. It is shown that the s and s2 approximations in the stationary neutron slowing down problems are connected with Wigner and Grueling-Goertzel approximations. A simple formula is given for time-dependent neutron slowing down. The influence of the field of gravity on the operation of a reactor and on the propagation of ultra cold neutrons is studied in the point-energy approximation. Also investigated is the neutron space-energy distribution in the field of gravity.
