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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Fusion Science and Technology
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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.”
Michiko Ahn Furudate, Seungyon Cho
Fusion Science and Technology | Volume 77 | Number 1 | January 2021 | Pages 51-56
Technical Paper | doi.org/10.1080/15361055.2020.1843313
Articles are hosted by Taylor and Francis Online.
The effects of temperature and pressure conditions on the equilibrium chemical compositions of purge gas at the outlet of the test blanket module (TBM) in the helium-cooled ceramic reflector (HCCR) are studied. As the chemical species in the equilibrium states, nine chemical species are considered: H, T, O, H2, HT, T2, H2O, HTO, and T2O. The mole fractions of these chemical species are calculated using a Gibbs free energy minimization method starting from the initial state of a H2-HTO mixture. The standard Gibbs free energies for the tritium species used in the study are calculated from the molecular constants obtained by a coupled-cluster calculation. The effects of pressure variations on the equilibrium compositions are shown to be negligible. The effects of temperature variations are also insignificant when the temperature exceeds 800 K. When the initial H2/HTO ratio is more than 10, more than 90% of tritium is expected to be recovered in the form of HT.
