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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.”
Walter Meyer, J. W. Leighty, J. W. Thiesing, D. H. Timmons
Nuclear Science and Engineering | Volume 60 | Number 4 | August 1976 | Pages 405-420
Technical Paper | doi.org/10.13182/NSE76-A26902
Articles are hosted by Taylor and Francis Online.
Albedos were experimentally determined for a spectrum of fast fission neutrons incident on a 24- × 24- × 9-in. concrete slab and a 24- × 24- × 6-in. cold-rolled steel slab. The experimental dose albedos were compared with those from Oak Ridge National Laboratory (ORNL) 05R Monte Carlo calculations and with orders-of-scattering calculations performed using readily available multigroup cross sections. The source of fast neutrons for the experimental studies was the Kansas State University Triga Mark II reactor; the direct and reflected neutron spectra were detected using a 2- × 2-in. liquid-scintillation spectrometer system. A computer code has been developed to normalize the experimental reflected spectra to a reference direct neutron beam measurement, to calculate the experimental dose albedos, and to evaluate the Monte Carlo dose albedos in terms of the experimental conditions. A comparison of the Monte Carlo and experimental results showed similar trends and structure, but the experimental dose albedos were smaller than the calculated ones by an average of 70 to 80%. The large energy bin widths and inaccuracies in the cross sections (errors up to 65%) used in the Monte Carlo calculations have contributed to the differences between the calculated and experimental results. Orders-of-scattering calculations for steel were performed using the ORNL DLC-2B 99-group cross-section set and similar calculations were performed for concrete using the DLC-9/FARS group cross-section set. In general, the orders-of-scattering calculated reflected spectra compare well with the experimental fast-neutron reflection spectra. Discrepancies arise in the orders-of-scattering calculated results at particular energies and scattering angles due to deficiencies identified in the multigroup compilations.