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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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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.”
Jeffrey A. Favorite
Nuclear Science and Engineering | Volume 152 | Number 2 | February 2006 | Pages 180-196
Technical Paper | doi.org/10.13182/NSE06-A2574
Articles are hosted by Taylor and Francis Online.
Variational perturbation theory is applied to internal interface perturbations in neutral-particle inhomogeneous transport problems. The leakage from a radioactive system is the quantity of interest. The Schwinger and Roussopolos variational functionals are used with volume- and surface-integral formulations of the integrals of perturbed quantities. In numerical one-dimensional spherical tests of source radius perturbations, the Roussopolos functional in the surface-integral formulation worked better when the source was large, and the Schwinger functional in the volume-integral formulation worked better when the source was small. A new variational functional is presented that formally allows a combination of the Schwinger and Roussopolos functionals; the contribution of each to the total estimate is adjusted with a parameter introduced in one of the trial functions. When the parameter is correctly chosen, the new functional is generally more accurate than either the Schwinger or Roussopolos functional alone. An analytic monodirectional slab transport problem is also considered.