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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.”
Tomohiro Kinjyo, Masabumi Nishikawa
Fusion Science and Technology | Volume 46 | Number 4 | December 2004 | Pages 561-570
Technical Paper | doi.org/10.13182/FST04-A591
Articles are hosted by Taylor and Francis Online.
This paper proposes a model to explain tritium release behavior of an irradiated Li4SiO4 sample made by Forschungszentrum Karlsruhe. The release curves were obtained in a series of experiments carried out using out-pile temperature programmed desorption techniques in the Kyoto University Reactor (KUR). Tritium release curves obtained for different purge gas compositions (N2, N2 + H2, N2 + H2O) were compared for selection of suitable conditions to determine the apparent diffusivity of tritium in a crystal grain of Li4SiO4.In the model formation, some mass transfer steps in the bulk of the crystal grain and those on the surface of the grain were taken into account, which were diffusion of tritium in the grain, adsorption and desorption of water on the surface of the grain, two types of isotope exchange reactions, and water formation reaction by the addition of hydrogen to the purge gas.Diffusivities of tritium in the crystal grain of Li4SiO4 were estimated using a curve-fitting method applied to the release curve obtained when the irradiated sample was purged by nitrogen with water vapor because of the fastest tritium release rate observed.