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The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
H. C. Claiborne, W. W. Engle, Jr.
Nuclear Technology | Volume 13 | Number 2 | February 1972 | Pages 209-215
Technical Paper | Shielding | doi.org/10.13182/NT72-A31055
Articles are hosted by Taylor and Francis Online.
Electronic components can be affected by the dose rate from gamma rays delivered during the first few shakes (10−8 sec/shake) of an exploding nuclear device. Determining such dose rates generally requires expensive time-dependent calculations. This paper demonstrates that relatively inexpensive steady-state transport calculations can be used to bracket time-dependent peak dose rates with meaningful upper and lower limits. The model configuration consisted of a sphere of air surrounded by a spherical annulus of concrete with an isotropic source of gamma rays from fissioning 235U located at the geometric center. Steady-state calculations were made with the discrete ordinates code ANISN and the time-dependent calculations with time-dependent ANISN (TDA). The upper limit dose rates were obtained by dividing the steady-state total dose by the pulse width of the device. This is equivalent to assuming that the uncollided and air-scattered fluxes arrive at the shield simultaneously. For a lower limit calculation, only the uncollided flux was considered incident on the shield. Calculations were made for a 120-cm-thick concrete shield for ranges of 500, 1000, and 5000 m and for step-function burst pulse widths of 1 through 8 shakes. The results from the steady-state calculations generally bracketed the peak time-dependent dose rates within an acceptably narrow band except for the 500-m range at the back end of the shield where the peak time-dependent dose rates were highest for all pulse widths. This apparent anomaly is explained on the basis of using a moving boundary condition in the time-dependent solution and the effect is shown to be of no consequence.