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Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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ANS Student Conference 2025
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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.”
Delgersaikhan Tuya, Hiroki Takezawa, Toru Obara
Nuclear Science and Engineering | Volume 188 | Number 1 | October 2017 | Pages 33-42
Technical Paper | doi.org/10.1080/00295639.2017.1337383
Articles are hosted by Taylor and Francis Online.
An approach to multiregion supercritical transient analysis based on the integral kinetic model (IKM) and Monte Carlo method is further developed with new features. The IKM describes the region-dependent fission rate during the transient in a system of arbitrary geometry using a secondary fission probability density function, which takes the explicit neutron transport time between successive fissions across the regions into account. The new features of the improved approach include treatment of the multiregion transient using repeated multidimensional linear interpolation between pre-obtained kinetic functions (i.e., secondary probability density function), a new method for calculating the kinetic functions using the continuous-energy Monte Carlo code MVP2.0, and utilization of kinetic functions directly in the IKM without the fitting function that introduces a fitting error. The improved approach is verified by applying it to the supercritical transient in simple Godiva systems of different region combinations without feedback. In addition, we attempt to validate the improved approach by applying it to the supercritical transient in a simplified Godiva system with thermal expansion feedback and compare the obtained and experimental results. The verification results indicate the improved approach works well with different combinations of regions while the validation results show promising agreement with the experimental results. This study is part of an ongoing research activity on the development of Multi-region Integral Kinetic (MIK) code for general space- and time-dependent kinetic analyses.