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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.”
F. Wagner, J. Baldzuhn, R. Brakel, B. Branas, R. Burhenn, J. Das, E. De La Luna, V. Erckmann, Y. Feng, S. Fiedler, L. Gianonne, P. Grigull, H.-J. Hartfuß, O. Heinrich, G. Herre, M. Hirsch, J.V. Hofmann, E. Holzhauer, R. Jaenicke, Ch. Konrad, G. Kocsis, W. Ohlendorf, P. Pech, F. Sardei, E. Wuersching, S. Zoletnik
Fusion Science and Technology | Volume 27 | Number 3 | April 1995 | Pages 32-39
Overview Paper | doi.org/10.13182/FST95-A11947043
Articles are hosted by Taylor and Francis Online.
We will give a summary on the status of H-mode studies on W7-AS stellarator. The major H-mode characteristics compare well with those known from the tokamak H-mode. All major characteristics of the H-mode are reproduced: The transition is spontaneous above a power and density threshold; particle and energy confinement improve simultaneously; a transport barrier at the edge develops with steep pressure gradients and ELMs appear; small scale fluctuations are strongly reduced and the development of a radial electric field is indicated by increased perpendicular impurity flow velocity. The temporal development of the transition seems to be distinctively slower than in tokamaks. The H-mode can be initiated by ECRH or NBI, respectively. The power threshold can be smaller than that of tokamaks. With ECRH, the density threshold is found to increase with heating power. The H-mode develops in small windows of the accessible iota range. These operational islands are characterised by a negative electric field already prior to the H-mode and a distinct maximum in space potential at the separatrix.