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This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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.”
Kenichi Yoshioka, Mitsuaki Yamaoka, Kouji Hiraiwa, Takanori Kitada
Nuclear Science and Engineering | Volume 195 | Number 1 | January 2021 | Pages 101-117
Technical Note | doi.org/10.1080/00295639.2020.1788847
Articles are hosted by Taylor and Francis Online.
The void reactivity of a fuel assembly with a streaming channel was measured in a simulated light water reactor critical lattice. The void reactivity was defined as the difference of reactivity ρ between different void conditions. Stainless steel and Zircaloy are candidates for the streaming channel material. Aluminum was used in this measurement because it is inexpensive and its absorption cross section is similar to that of Zircaloy. Two types of streaming channels were used: one made of aluminum and the other made of stainless steel. The two streaming channels were compared in terms of the difference in void reactivity. Measured values were calculated using a continuous-energy Monte Carlo code, MCNP6.1, with the JENDL-4.0 and ENDF/B-VIII.0 nuclear data libraries. The measured values and the calculated values agree within an error range of approximately 10% for the aluminum streaming channel and approximately 20% for the stainless steel streaming channel. The streaming effect of reactivity was deduced from the changes of migration area and buckling, which were measured using the water-height coefficient of reactivity and the axial fission-rate distribution.