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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.”
Kiyoshi Yoshikawa, Yoshihiko Nimura, Yasushi Yamamoto, Hiroshi Watanabe+
Fusion Science and Technology | Volume 17 | Number 4 | July 1990 | Pages 527-539
Technical Paper | Beam Direct Conversion | doi.org/10.13182/FST90-A29189
Articles are hosted by Taylor and Francis Online.
A beam direct energy converter (BDC) is designed to recover unneutralized ion beam energies in a 500-keV negative-ion-based deuterium neutral beam injection system for the Fusion Experimental Reactor of Japan Atomic Energy Research Institute. A newly developed three-dimensional beam transport code KUNABE-3 is used. Due to approximately equal fractions of unneutralized D+ and D− beams flowing from the gas neutralizer, electrostatic electron suppression is efficient. Also, magnetic separation and deflection of both species by a 1-kG magnetic field are efficiently applicable. Under suitable energy recovery conditions, perfect collection of both positive and negative ion beams is theoretically achievable, even for a collector voltage of ±480 kV, resulting in 96% energy recovery efficiency. Within ±10% deviation from the reference parameters, the designed BDC shows excellent performance for such parameters as magnetic fields, incident beam energies, and gas line densities. Secondary electrons emitted from the negative ion collector for D− collection are also almost completely prevented from escaping if an auxiliary electrode controlling local electric field near the electrode surface is used.