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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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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.”
Yasunori Yamanaka, Shinya Mizokami, Manabu Watanabe, Takeshi Honda
Nuclear Technology | Volume 186 | Number 2 | May 2014 | Pages 263-279
Technical Paper | Reactor Safety | doi.org/10.13182/NT13-46
Articles are hosted by Taylor and Francis Online.
Because of the Great East Japan Earthquake, and the resulting tsunami, which occurred on March 11, 2011, a serious accident occurred in Units 1, 2, and 3 of the Fukushima Daiichi nuclear power station. Since the accidents, data from interviews with operators and on-site surveys have been continuously compiled. Based on the data, a plant-state analysis has been conducted using the severe accident analysis code MAAP (Modular Accident Analysis Program). Parallel to the MAAP analysis, the responses of the plant to site operations, such as water injection, are analyzed, and core conditions are comprehensively evaluated. According to the evaluation, in Unit 1, it is presumed that almost no fuel was left at the original position; it was molten and moved downward. The fuel likely damaged the reactor pressure vessel (RPV), and it is assumed that most of it had dropped to the primary containment vessel (PCV) pedestal. In Units 2 and 3, it is presumed that some of the fuel was left at the original position and the rest dropped to the bottom of the RPV or to the PCV pedestal. In the MAAP analysis, the behavior of the plants before core melt is reproduced. However, RPV damage of Units 2 and 3 does not occur in the MAAP analysis, which is contrary to the observed facts. This shows that the analysis capability of the current MAAP code is limited. Therefore, by developing severe accident analysis codes to achieve higher levels of accuracy and by evaluating the plant responses to site operation, we will continue to obtain a clear picture of the states inside the reactor so that fuel debris can be removed.