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Education, Training & Workforce Development
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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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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. T. Mihalczo, E. D. Blakeman, V. K. Paré, T. E. Valentine, D. J. Auslander
Nuclear Technology | Volume 103 | Number 3 | September 1993 | Pages 346-379
Technical Paper | Nuclear Criticality Safety | doi.org/10.13182/NT93-3
Articles are hosted by Taylor and Francis Online.
The subcritical neutron multiplication factors k for two parallel, axially separated, flat cylindrical tanks separated up to 57.91 cm in air and containing enriched uranyl (93.1 wt% 235U) nitrate solution (71.6-cm-i.d. tanks, 8.91-cm solution thickness, 1.555 g/cm3 solution density, and 404 g U/ℓ uranium density) were measured by the 252Cf-source-driven noise analysis method with measured k values varying from 0.99 to 0.80. These measurements were performed at the Los Alamos National Laboratory (LANL) Critical Experiments Facility in 1989 and were part of the program of Westinghouse Idaho Nuclear Company (WINCO) to benchmark calculations for the design of the new storage system at Idaho National Engineering Laboratory. Initial subcriticality measurements by the source-jerk method at LANL had indicated that at a calculated neutron multiplication factor k = 0.95, the measured k was 0.975. This discrepancy was of concern to WINCO because the new storage facility was being designed with a k limit of 0.95, and thus, half of the criticality safety margin of the storage design was equal to the discrepancy between early measurements and calculations. The 252Cf-source-driven noise analysis measurements confirmed the validity of the calculational methods. In addition to providing the neutron multiplication factor from point-kinetics interpretation of the data, these measurements also provided the auto-power and crosspower spectral densities as a function of frequency, which can be calculated directly with recently developed Monte Carlo methods and thus could also be used to validate calculational methods and cross-section sets. As with previous measurements with loosely coupled systems, a modified point-kinetics interpretation was successfully used to obtain neutron multiplication factors for measurements with the californium source and detectors located on the same tank. Although the californium source is located on axis but asymmetrically in the system, the detectors adjacent to the radial surface were sufficiently far apart that the correlated information was from long fission chains, which are distributed throughout the system of two tanks. The subcritical neutron multiplication factors obtained from the break frequency noise analysis method agreed with those from the 252Cf-source-driven noise method. These measurements confirmed the criteria from previous experiments for location of the source and detectors to obtain the neutron multiplication factor by using a modified point-kinetics interpretation of the data and again verified the usefulness of this method for interacting systems.
