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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.”
Yoshinori Miyoshi, Takuya Umano, Kotaro Tonoike, Naoki Izawa, Susumu Sugikawa, Shuji Okazaki
Nuclear Technology | Volume 118 | Number 1 | April 1997 | Pages 69-82
Technical Paper | Kiyose Birthday Anniversary Special / Nuclear Criticality Safety | doi.org/10.13182/NT97-A35358
Articles are hosted by Taylor and Francis Online.
A series of critical experiments with 10% enriched uranyl nitrate solution using a cylindrical core tank 60 cm in diameter have been performed with the Static Experiment Critical Facility at the Nuclear Fuel Cycle Safety Engineering Research Facility in the Tokai research establishment of the Japan Atomic Energy Research Institute. In the first series of experiments using the cylindrical core tank, systematic data of the critical height for water-reflected cores and unreflected cores were obtained by changing the uranium concentration of the fuel solution from 313 to 225 g U/ℓ. As the reactivity of each core is controlled only by solution height, these criticality configurations, which have simple cylindrical shapes, are available for the validation of calculation codes used in criticality safety designs of nuclear fuel cycle facilities. The neutron multiplication factors of experimental cores were calculated with the two-dimensional transport code TWOTRAN in the SRAC code system and with the continuous-energy Monte Carlo code MCNP4A, employing the Japanese evaluated nuclear data library JENDL-3.2. The calculations from the combination of these calculation codes and the nuclear data library reproduce the neutron multiplication factors within an error of 0.9% for the experimental configuration of critical cores.