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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).
C. B. Bigham
Nuclear Science and Engineering | Volume 59 | Number 1 | January 1976 | Pages 50-52
Technical Note | doi.org/10.13182/NSE76-A26808
Articles are hosted by Taylor and Francis Online.
The fission cross sections for 233U, 235U, 239Pu, and 241Pu reported in 1958 have been revised using the very precise, recently published, specific activities 21 405 ± 20 dpm/µg 233U, 4798.1 ± 3.3 dpm/mg 235U, and 746.19 ± 0.41 dpm/mg 238U. Revised ratios of fission cross sections at 2200 m/sec are: 233U/235U = 0.9142 ± 0.0012, 239Pu/235U = 1.2876 ± 0.0034, 239Pu/ 233U = 1.4084 ± 0.0036, and 241Pu/239Pu = 1.3506 ± 0.007. Revised fission cross sections at 200 m/sec in barns relative to σc(197 Au) = 98.7 ± 0.2 are: σf(233 U) = 527.4 ± 3.1 σf(235 U) = 576.9 ± 3.4, σf(239 Pu) = 742.8 ± 4.4, and σf(241 Pu) = 1003.3 ± 5.2. The errors do not include g-factor errors of ±0.2% for 233U, ±0.155% for 235U, ±0.285% for 239Pu, and ±0.7% for 241Pu.