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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.”
K. Chen, C. A. Erdman, M. F. Kennedy, A. B. Reynolds
Nuclear Science and Engineering | Volume 83 | Number 4 | April 1983 | Pages 459-472
Technical Paper | doi.org/10.13182/NSE83-A18649
Articles are hosted by Taylor and Francis Online.
A homogeneous nucleation-condensation growth model was developed for calculating particle-size distributions measured in capacitor discharge vaporization (CDV) experiments conducted at the Oak Ridge National Laboratory. Uranium dioxide pellets were partially vaporized in an argon environment by rapid energy deposition through capacitor discharge. This was followed by rapid expansion and subsequent condensation of the UO2 vapor. Measured primary particle-size distributions of the resulting aerosols were lognormal, with a geometric mean particle diameter of (0.014 ± 0.002) µm and a geometric standard deviation of 1.7 ± 0.1. It was postulated that the expanding UO2 vapor compressed the surrounding argon as in a spherical shock tube and that the aerosol was generated by homogeneous nucleation and condensation growth in the resulting rarefaction wave. The calculated motion of the U02-argon interface is in approximate agreement with the movies of the expansion process. The calculated particle-size distributions are in agreement with the measured distributions except at the large particle end. This agreement indicates that the small primary particles from the CDV tests resulted from homogeneous nucleation and condensation growth, as assumed in the analytical model.