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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
Naphtali M. Mokgalapa, Tushar K. Ghosh, Sudarshan K. Loyalka
Nuclear Technology | Volume 186 | Number 1 | April 2014 | Pages 45-59
Technical Paper | Reactor Safety | doi.org/10.13182/NT13-9
Articles are hosted by Taylor and Francis Online.
In high-temperature gas reactors, graphite particle adhesion and resuspension from structural surfaces play a role in source term estimations. This paper describes measurements of the adhesion force between an irregular graphite cluster (henceforth called a graphite particle) and Hastelloy X samples having different surface conditions. An atomic force microscope (AFM) was used. The graphite particle was attached to the AFM probe and then brought directly into and out of contact with the surface in air; the adhesion force was obtained from the resultant force curve. The adhesion forces of the graphite particle with Hastelloy X (as received, polished, and different oxidations) and mica surfaces were determined. From the resulting adhesion forces, the work of adhesion W12 (energy per unit area) was calculated. Although the values of the measured pull-off (adhesion) forces were found to be of the same order of magnitude, they differed by surface condition depending where on the sample the adhesion force was measured. The theoretical value of the adhesion force was calculated using the theory of Johnson, Kendall, and Roberts. When compared to the values calcluated from this theory, the measured values were lower by a factor of 100 in some cases and 1000 in others. This difference may be due to the approximation of the irregular graphite cluster probe as a perfect graphite particle sphere and to not taking into consideration asperities on the surface of the particle probe. Additionally, covalent bonds may form between the surface elements and the graphite particle because of the applied load. In this paper, the effects of oxidation on the adhesion of graphite particles to the mica and Hastelloy X surfaces are also discussed.