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Fusion Science and Technology
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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.”
Hiroo Numata, Izumi Ohno
Fusion Science and Technology | Volume 38 | Number 2 | September 2000 | Pages 206-223
Technical Paper | doi.org/10.13182/FST00-A143
Articles are hosted by Taylor and Francis Online.
The physicochemical properties of the Pd-H system were studied by in situ potentiometric, resistance, and dilatometric measurements in each of three applied pulse modes, A, B, and C, and repeated H absorption and desorption. Potential, resistance ratio, and an increase in dilation (l/l0) were measured simultaneously after H equilibrium was attained with the Pd electrode. During continuous absorption, structural phase transition ( [right arrow] ) and void formation occurred, and the values of the H/Pd ratio in the limiting phase, in the + phase coexistence, and in the transition and the +voids coexistence regions are consistent with those obtained from the Pd-H isotherm at 40°C. Hydrogen absorption caused the dilation, from whose slope the molar volume was obtained as 0.64 ( phase) and 0.40 ( + phase) cm3/mol. The resistance increased in proportion to the H/Pd ratio and was kept constant at 1.7 to 1.8 over Rtr.For the first absorption through the phase (>min), the electrode potential shifted with an increase in dilation, which suggests nonequilibrium PdH2-x precipitation followed by conversion to the phase and void formation. Although there was a remarkable lack of any dependence on the number of repetitions of the values of the limiting resistance and potential corresponding to the + and + void coexistence, the onset of the phase, min, increased as the number of repetitions increased. The volumetric ratio for an increase in the H/Pd ratio corresponds to the absorption in high-density defect areas surrounding voids. During repeated absorption and desorption in the C applied pulse mode, the apparent molar volumes of the + phase coexistence show that absorption proceeds inhomogenously, in contrast to the first absorption in the A applied pulse mode.