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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.”
R. Kladnik.
Nuclear Science and Engineering | Volume 17 | Number 2 | October 1963 | Pages 185-191
Technical Paper | doi.org/10.13182/NSE63-A28877
Articles are hosted by Taylor and Francis Online.
The stationary velocity-dependent transport equation for an infinite homogeneous source-free medium is solved by expanding the solution into a power series of the eigenvalues κ = 1/L. The integral equations, obtained by equating terms with the same κ0m, have been solved numerically on the IBM 704 computer using the iteration procedure. The monatomic gaseous model for the scattering process has been used assuming scattering cross section to be independent of the relative velocity and the absorption cross section to follow the 1/v law. A general expression for the diffusion coefficient in the absorbing medium has been obtained whereas the diffusion length L is obtained as the only positive real root of an algebraic equation whose order depends on the degree of the approximation. A comparison between the calculated and measured values of the diffusion length in poisoned water shows that water can be described roughly as a monatomic gas with A = 1.9 and ls(∞) = 0.40 cm. An empirical formula for the effective temperature of the neutron velocity distribution is evaluated.