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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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.”
Ching-Hor Lee, Shi-Ping Teng
Nuclear Technology | Volume 101 | Number 1 | January 1993 | Pages 67-78
Technical Paper | Waste Management Special / Radioactive Waste Disposal | doi.org/10.13182/NT93-A34768
Articles are hosted by Taylor and Francis Online.
An analytical solution covering the entire range of sorption properties of rock has been derived for the migration of radionuclides along a discrete fracture in a porous rock matrix. The analysis takes into account the advective transport in the fracture, longitudinal hydrodynamic dispersion in the fracture, molecular diffusion from the fracture into the rock matrix, adsorption within the matrix, and the radioactive decay. For adsorption of radionuclide within the matrix, the effects of no sorption, linear nonequilibrium sorption, and linear equilibrium sorption are integrated into a generic transient analytical solution. Based on certain assumptions, the problem can be formulated into two coupled one-dimensional transport equations: one for the fracture and another for the porous matrix in a direction perpendicular to the fracture axis. The general solution is of a single semi-infinite integral form that can be evaluated by Gaussian quadrature. The results indicate that the assumption of equilibrium sorption within the rock results in underestimation of the concentration profile along the fracture in the early stages of migration. It is worth noting that the concentration profile of the nonequilibrium sorption case is slightly smaller than that of the equilibrium sorption case after a certain time. However, the profiles eventually approach the same value. It is also confirmed that the porosity of rock strongly affects radionuclide transport in a fracture.
