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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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
BWXT will scout potential TRISO fuel production sites in Wyoming
BWX Technologies Inc. announced today that its Advanced Technologies subsidiary has signed a cooperation agreement with the state of Wyoming to evaluate locations and requirements for siting a potential new TRISO nuclear fuel fabrication facility in the state.
A. D. Whapham
Nuclear Technology | Volume 2 | Number 2 | April 1966 | Pages 123-130
Technical Paper | doi.org/10.13182/NT66-A27492
Articles are hosted by Taylor and Francis Online.
The structure of post-irradiation annealed UO2 has been examined by transmission electron microscopy to try to understand the behavior and release of fission gas. At a dose of 2.2 × 1019 fissions/cm3, 5 × 1015 small gas bubbles/cm3 are observed in the material. These precipitate at 1100°C and appear to grow from 25 to 100-Å diam at 1500°C by diffusion of gas atoms from the matrix. Grain-boundary migration sweeps up these bubbles at between 1800 and 2000°C. Re-solution of fission-gas bubbles up to 300-Å diam has been demonstrated on re-irradiation. At a dose of 1.6 × 1020 fissions/cm3, bubbles appear to grow by coalescence and by dislocation sweeping. Precipitates, believed to be solid fission products, are observed. It is concluded that, in a fuel element in which a high-temperature gradient exists, the gas release below 1800°C will be controlled by the migration of bubbles to grain boundaries and by the degree of linking up between the gas-filled voids produced at grain boundaries. At temperatures above 1800°C, large gas-filled voids produced at grain boundaries would be expected to migrate up the temperature gradient by the vapor-transfer mechanism, continuing the process of sweeping up most of the gas started by the initial grown-in porosity.