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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.
W. G. Winn, P. B. Parks, N. P. Baumann, C. E. Jewell
Nuclear Science and Engineering | Volume 65 | Number 2 | February 1978 | Pages 254-272
Technical Paper | doi.org/10.13182/NSE78-A27155
Articles are hosted by Taylor and Francis Online.
Unsymmetric perturbations were introduced into the core of a large, critical, heavy-water-moderated, multiregional reactor. The resulting three-dimensional changes in flux level and shape with time were measured. Perturbations included: 1. Free-fall insertion of rods near the reactor center. Each rod contained 235U slugs in the bottom half and lithium slugs in the top half 2. Free-fall insertion of rods into an off-center radial position. Each rod contained 235U slugs in the bottom half and aluminum in the top half. 3. Withdrawal of cadmium control rods from the central 20% of the reactor core. Flux tilts calculated with the TRIMHX code were within 5% of measured flux tilts. TRIMHX provides a three-dimensional (hex-z geometry) solution of the few-group neutron diffusion and delayed precursor equations without feedback. Inputs to the calculations are available in sufficient detail to allow other methods of solution to be tested.