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Fusion Energy
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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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.”
Fu-Long Chen, Shih-Hai Li
Nuclear Technology | Volume 90 | Number 2 | May 1990 | Pages 215-225
Technical Paper | Radioacitive Waste Management | doi.org/10.13182/NT90-A34416
Articles are hosted by Taylor and Francis Online.
To analytically predict the transport of radionuclides in porous media, it is necessary to develop a complete mathematical model. This means that the mechanisms must be described and the governing equations derived, along with their general solutions for the transport processes. The four major mechanisms—ad-vection, dispersion, adsorption-desorption and ion exchange, and degradation—are physically described and mathematically modeled. Based on the classic principle of mass conservation in a control volume, the governing equation for the transport of radionuclides in porous media is derived, which may be called the advection-dispersion equation. Some general solutions of the governing equation are obtained by using constant dispersion coefficients. In addition, some ambiguities of the advective-dispersion equation are solved, and this equation is extended to fractured media.
