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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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Latest News
ANS designates Armour Research Foundation Reactor as Nuclear Historic Landmark
The American Nuclear Society presented the Illinois Institute of Technology with a plaque last week to officially designate the Armour Research Foundation Reactor a Nuclear Historic Landmark, following the Society’s decision to confer the status onto the reactor in September 2024.
G. S. Brunson
Nuclear Technology | Volume 10 | Number 1 | January 1971 | Pages 33-43
Technical Paper and Note | Reactor | doi.org/10.13182/NT71-A30945
Articles are hosted by Taylor and Francis Online.
As part of the defective-cladding detection program at Experimental Breeder Reactor II, the Reactor Cover Gas Monitor was installed to provide on-line monitoring for noble gas fission products in the argon cover gas which fills the reactor vessel above the sodium coolant. With a 2- × 2-in. sodium iodide scintillator as the detector, it has been possible to identify 133Xe, 85mKr, and 135Xe, which are always present in low concentrations due to an irreducible background fission source in the reactor. This apparently straightforward monitoring project turned out to be much complicated by the presence of relatively large concentrations of 23Ne [from the reaction 23Na(n, p)23Ne on the sodium coolant]. The 23Ne diffuses from the sodium to the cover gas at a rate which is exceedingly sensitive to the bulk sodium temperature. Small temperature changes can produce large changes in the 23Ne concentration. The Compton continuum from 23Ne is counted in the channels adjusted for the fission product gases, causing large and alarming surges in the indicated concentrations. While this effect is not yet understood, it has been alleviated by “aging” the sample stream in a delay line to permit additional decay of the 38-sec 23Ne. After the delay line was installed, it was possible to monitor 135Xe very effectively; 133Xe and 85mKr still could not be monitored clearly because of the interference from the Compton continua of higher energy gamma lines, principally that of 135Xe.
