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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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Latest News
High temperature fission chambers engineered for AMR/SMR safety and performance
As the global energy landscape shifts towards safer, smaller, and more flexible nuclear power, Small Modular Reactors (SMRs) and Gen. IV* technologies are at the forefront of innovation. These advanced designs pose new challenges in size, efficiency, and operating environment that traditional instrumentation and control solutions aren’t always designed to handle.
Dwight W. Underhill
Nuclear Technology | Volume 8 | Number 3 | March 1970 | Pages 255-260
Paper | Fuel | doi.org/10.13182/NT70-A28672
Articles are hosted by Taylor and Francis Online.
Exact equations for the experimental analysis of fission-gas holdup beds are developed by the method of statistical moments. The mean retention time, given by the first moment, is independent of the factors which affect mass transfer. This independence emphasizes the important fact, sometimes overlooked in the analysis of fission-gas holdup beds, that the true dynamic adsorption coefficient for a stable fission-gas isotope is identical to the static adsorption coefficient. The second moment, used in combination with the first moment, describes the spreading of the input after it has passed through the holdup bed. The meaning of these equations is examined in detail, and by their correct use the factors needed for the design of fission-gas holdup beds can be determined rapidly from laboratory experiments. This method of analysis is applied to data obtained from fronts of dilute 85Kr passed through charcoal beds.
