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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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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TVA nominees promise to support advanced reactor development
Four nominees to serve on the Tennessee Valley Authority Board of Directors told the Senate Environment and Public Works Committee that they support the build-out of new advanced nuclear reactors to meet the increased energy demand being shouldered by the country’s largest public utility.
S. J. Altschuler, C. L. Schuske
Nuclear Technology | Volume 13 | Number 2 | February 1972 | Pages 131-147
Technical Paper | Reactor | doi.org/10.13182/NT72-A31048
Articles are hosted by Taylor and Francis Online.
Two models are described for calculating critically safe storage configurations for uranium (93.4% 235U) and plutonium (96% 239Pu, 4% 240Pu) metal. The first model deals with conventional arrays in air of fissile units surrounded by concrete walls. The model uses the concepts of surface density and unit surface-to-volume ratio to define safe-array parameters. The second model makes use of thick internal moderators (i.e., water) enclosing each storage unit in an array. These arrays are also surrounded by concrete walls. The internal moderators partially isolate adjacent storage units from one another and thus, in some cases, permit extremely high surface densities and vault loading. Several factors that influence the storage model are shape and density of the individual storage units and the degree of reflection of arrays of units.
