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Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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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.”
Samuel E. Bays, J. Stephen Herring, James Tulenko
Nuclear Technology | Volume 173 | Number 2 | February 2011 | Pages 115-134
Technical Paper | Fission Reactors | doi.org/10.13182/NT11-A11542
Articles are hosted by Taylor and Francis Online.
An axially heterogeneous sodium-cooled fast reactor design is developed for converting minor actinide waste isotopes into plutonium fuel. The reactor design incorporates zirconium hydride moderating rods in an axial blanket above the active core. The blanket design traps the active core's axial leakage for the purpose of transmuting 241Am into 238Pu. This 238Pu is then co-recycled with the spent driver fuel to make new driver fuel. Because 238Pu is significantly more fissionable than 241Am in a fast neutron spectrum, the fissile worth of the initial minor actinide material is upgraded by its preconditioning via transmutation in the axial targets. Because the 241Am neutron capture worth is significantly greater in a moderated epithermal spectrum than the fast spectrum, the axial targets serve as a neutron trap that recovers some of the axial leakage lost by the active core.A low transuranic conversion ratio is achieved by a degree of core flattening that increases axial leakage. Unlike a traditional "pancake" design, neutron leakage is recovered by the axial target/blanket system. This heterogeneous core design is constrained to have sodium void and Doppler reactivity worth similar to that of an equivalent homogeneous design. Contrary to a homogeneous design, concentrating minor actinides (MAs) in an axial blanket mitigates the problem of above-threshold multiplication during sodium voiding. Because minor actinides are irradiated only once in the axial target region, elemental partitioning of the minor actinides from plutonium is not required. This fact enables the use of metal targets with pyroprocessing. After reprocessing, the target's newly bred 238Pu and remaining unburned MAs become the feedstock for the next batch of driver fuel.