ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
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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Nuclear Science and Engineering
May 2025
Nuclear Technology
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Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
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.
