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Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
G. Kessler
Nuclear Science and Engineering | Volume 159 | Number 1 | May 2008 | Pages 56-82
Technical Paper | doi.org/10.13182/NSE159-56
Articles are hosted by Taylor and Francis Online.
The three most important americium isotopes, 241Am, 242mAm, and 243Am originate in the nuclear fuel of pressurized water reactors (PWRs), fast reactors (FRs), or accelerator-driven systems (ADSs) in a ratio of 241Am/243Am between ~0.45/0.55 to ~0.85/0.15. The content of 242mAm in the spent fuel of PWRs, FRs, and ADSs is relatively small and varies between 0.08 and 4.5%. Only by dedicated breeding in 241Am fuel and blanket assemblies could this 242mAm content be increased to ~7%. Only the isotope 241Am has a relatively high alpha-particle heat production whereas the isotopes 242mAm and 243Am have a relatively small alpha-particle heat production. All three americium isotopes are spontaneous fission neutron emitters.In this paper the different isotopic compositions of the three americium isotopes, 241Am, 242mAm, and 243Am are assembled for a number of fuel cycle strategies for PWRs, FRs and ADSs. Then, the critical masses, spontaneous fission neutron sources, and alpha-particle heat power of these different americium compositions are calculated. In a preignition analysis for gun systems and implosion systems, it is shown that only the implosion system would be applicable to the considered americium isotopic compositions. A subsequent thermal analysis with assumptions for the geometry and choice of materials of so-called hypothetical nuclear explosive devices (HNEDs) shows that the high alpha-particle heat power in the fissile reactor americium part would lead to such high temperatures that the surrounding chemical high explosives would melt and self-explode, and the americium metal would melt.Such HNEDs on the basis of reactor americium as fissile material would be technically unfeasible.
