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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
F. Botta, C. Hellwig
Nuclear Science and Engineering | Volume 135 | Number 2 | June 2000 | Pages 165-176
Technical Paper | doi.org/10.13182/NSE00-A2132
Articles are hosted by Taylor and Francis Online.
Nuclear fuel can be fabricated and used in the form of microspheres (sphere-pac fuel). The heat transport mechanisms in fuel pins containing sphere-pac fuel are however very different from those in pellet pins. They are controlled not only by the thermal conductivity of fuel, cladding, and fill gas but also by particle sizes and packing density, by their state of sintering, and by radiation and gas pressure. A theoretical model is presented accounting for all these parameters, but still simple and fast enough to be implemented into a fuel pin modeling code. The basic geometrical element for this model is derived from the orthorhombic packing. For calculation of a binary package, four different radial zones within the basic element are distinguished, i.e., neck zone, gas zone, infiltrated zone, and bypass zone. The method presented here combines an analytical one-dimensional treatment with a radial heat flow relaxation procedure simulating the second (radial) dimension. Results are compared with experimental and theoretical data from the literature. With the model presented here, sophisticated modeling of sphere-pac fuel pins is possible.