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The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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.”
Pavel Hejzlar, Michael J. Driscoll, Mujid S. Kazimi
Nuclear Science and Engineering | Volume 139 | Number 2 | October 2001 | Pages 138-155
Technical Paper | doi.org/10.13182/NSE01-A2228
Articles are hosted by Taylor and Francis Online.
A conceptual design of a lead-bismuth-eutectic (LBE)-cooled actinide burner core with innovative streaming fuel assemblies (FAs) is described. The 1800-MW(thermal) core employs metallic, fertile-free fuel where the transuranics (plutonium plus minor actinides) are dispersed in a zirconium matrix. The core contains 157 streaming FAs that enhance neutron streaming by employing gas-filled, sealed streaming tubes at the FA periphery and center. The large reactivity excess at the beginning of life is compensated for by a system of double-entry control rods. The arrangement of top-entry and bottom-entry control rods in a staggered pattern allows the achievement of a very uniform axial power profile and a small reactivity change from control rod driveline expansion. The reactor can operate with an 18- to 24-month cycle length.Safety is provided through negative reactivity coefficients and tight neutronic coupling. The void coefficient is negative for a partially as well as a fully voided core. The effective delayed neutron fraction is 25% less than that of typical oxide-fueled fast reactors, making the requirements on reactor control performance more demanding. The Doppler coefficient is negative with a magnitude appreciably lower than the typical values of oxide fuels in sodium-cooled reactors, but comparable to the values observed in integral fast reactor (IFR) cores with metallic U-Pu-Zr fuels. The fuel thermal expansion coefficient is also negative, having a magnitude approximately equal to the Doppler coefficient. In terms of the transuranic destruction rate per MW(thermal) per effective full-power year, the design is comparable to accelerator-driven systems (ADSs). Long-lived fission products also can be transmuted, albeit at lower incineration efficiency than in ADSs.