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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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.”
Joseph A. Christensen, R. A. Borrelli
Nuclear Science and Engineering | Volume 196 | Number 1 | January 2022 | Pages 98-108
Technical Paper | doi.org/10.1080/00295639.2021.1940066
Articles are hosted by Taylor and Francis Online.
Algorithms used to generate Monte Carlo input decks and to analyze the output over a range of uranium mass, water volume, and particle size in a regular lattice are described. The algorithms produce input decks for both homogeneous and heterogeneous, regular-lattice systems of 20% enriched uranium metal and water and then analyze the results to determine the minimum critical mass over a range of input mass and particle size. The output is presented and analyzed for a 20% enriched uranium metal and water system, and comparisons to existing technical reports and safety guides are discussed. Two particular existing recommendations are tested and compared with new results: the boundary between a homogeneous system and a heterogeneous system, and the recommended margins of safety that can be applied to account for the effects of heterogeneity.
