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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.”
Franco Vittorio Frazzoli, Romolo Remetti, Sergio Guardini, Valeri Maiorov
Nuclear Technology | Volume 126 | Number 2 | May 1999 | Pages 205-214
Technical Paper | Reprocessing | doi.org/10.13182/NT99-A2968
Articles are hosted by Taylor and Francis Online.
The presence of Pu X-ray peaks in the gamma spectrum of Pu-bearing materials [for example, PuO2 and mixed-oxide (MOX) samples] is commonly attributed to alpha and gamma excitation. The aim of this work is the development of a mathematical model, based on the "thick target yield" approach, for both alpha- and gamma-induced fluorescence processes, thus enabling the quantification of the relative importance of these effects and the interpretation of the experimental data.Experimental data obtained at the Performance Laboratory (European Commission, Joint Research Center, Ispra, Italy) from well-characterized PuO2 and MOX samples under well-defined experimental conditions are compared with the expected values based on the model developed, taking into account special self-attenuation of X rays from induced effects.Finally, a feasible application of the model is considered concerning the field of nuclear material accountancy and control; the possibility of inferring U and Pu concentrations in MOX from the normalized Pu K-shell X-ray counting rate is considered, and the expected performances are given.