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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Chris Wagner: The role of Eden Radioisotopes in the future of nuclear medicine
Chris Wagner has more than 40 years of experience in nuclear medicine, beginning as a clinical practitioner before moving into leadership roles at companies like Mallinckrodt (now Curium) and Nordion. His knowledge of both the clinical and the manufacturing sides of nuclear medicine laid the groundwork for helping to found Eden Radioisotopes, a start-up venture that intends to make diagnostic and therapeutic raw material medical isotopes like molybdenum-99 and lutetium-177.
R. A. Krakowski, R. L. Hagenson, G. E. Cort
Nuclear Technology | Volume 34 | Number 2 | July 1977 | Pages 217-241
Technical Paper | Reactor | doi.org/10.13182/NT77-A39699
Articles are hosted by Taylor and Francis Online.
The thermal-mechanical response of the Reference Theta-Pinch Reactor (RTPR) first wall was analyzed. The first wall problems anticipated for a pulsed, high-β fusion power plant can be ameliorated by either alterations in the physics operating point, materials reengineering, or blanket/first wall reconfiguration. Within the latter “configuration” scenario, a two-fold approach has been adopted for the thermal-mechanical portion of the RTPR first wall technology assessment. First, a number of new first wall configurations (bonded or unbonded laminated composites, all-ceramic structures, protective and/or sacrificial “bumpers”) were considered. Second, a more quantitative failure criterion, based on the developing theories of fracture mechanics, was identified. For each first wall configuration, transient heat transfer and thermoelastic stress calculations have been made. Two-dimensional finite element structural analyses have been made for a variety of mechanical boundary conditions. Only the Al2O3/Nb—1 Zr system has been considered. The results of this study indicated a wide range of design solutions to the pulsed thermal stress problem anticipated for the RTPR. The use of first wall bumpers, in particular, results in significant (a factor of ∼10) reduction in first wall thermal stresses, although simply reducing the insulator thickness also leads to acceptable stress levels. The means by which the first wall portion of the RTPR blanket segment is attached has a minor influence on the stress distribution, although more accurate two-dimensional thermal modeling of the first wall yields stresses that may be reduced by 40% of those predicted by the one-dimensional calculations used heretofore. Static fatigue life estimates of both all-ceramic and ceramic-metal first walls are in excess of five years for even the most severe conditions envisaged for the RTPR. Finally, relatively minor changes in the physics operating point were proven to reduce dramatically the RTPR first wall problem.