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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.”
J. M. Fletcher, C. J. Hardy
Nuclear Science and Engineering | Volume 16 | Number 4 | August 1963 | Pages 421-427
Technical Paper | doi.org/10.13182/NSE63-A26554
Articles are hosted by Taylor and Francis Online.
The extraction by TBP of nitrato complexes of metals occurs mainly by the formation of nonconducting complexes in which the oxygen of the PO group is covalently bound to the metal, e.g., P==0 → M. In other TBP complexes, this O atom is bonded to hydrogen, e.g., to a hydrogen atom of water, of an undissociated acid, or of the hydronium ion. Three features in the extraction of metal nitrates at trace concentration from nitric acid concentrations >7M which await interpretation are the second increase in the distribution coefficient, DM; the decrease in the magnitude of this second increase as the fraction of inert diluent increases; and the change in the temperature coefficient of DM from negative to positive. Extraction (i) by bonding of the phosphoryl oxygen to an aquo group (of the aquonitrato metal complex), or (ii) by nitrato acids, do not explain these features. Measurements of the conductivity and viscosity of 100% TBP-HNO3-H2O phases are consistent with the existence of three steps as the ratio HNO3/TBP increases. In the first step, ions, postulated as (TBP·H2O·H)3O+ and (TBP·H)2(H2O·H)O+, are formed. In the second step, the molar conductivity decreases as the predominant species becomes TBP·HNO3. In the third step the molar conductivity and the water content increase by the formation of ions such as (TBP·H)(H2O·H)(HNO3·H)O+, in which a nitric acid molecule is bonded to the hydronium ion: the second increase in DM for certain metals is explained by there being similar bonding, through the oxygen of a nitrato group of the metal complex, in place of the HNO3 in this complex ion when HNO3/TBP is >1. The positive temperature coefficient shown by this form of extraction of metal nitrates is also shown in this region by the extraction of nitric acid, the conductivity, and the water content.