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Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Shlomo Ron, Judah Tzoref, Doron Gal
Nuclear Technology | Volume 97 | Number 3 | March 1992 | Pages 294-302
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT92-A34637
Articles are hosted by Taylor and Francis Online.
The amount of fission product release during a core heatup accident in a medium-sized high-temperature gas reactor depends on the size of the inadvertent opening in the primary circuit; this dependence is assessed. The opening triggers a depressurization event that is assumed to be coupled with the failure of the forced circulation in both decay-heat removal systems. The scenario investigated is a beyond-design-base accident. The DSNP modular simulation code is used. A two-dimensional model is developed to simulate the HTR-500 design. The study shows that the depressurization process does not contribute significantly to the sweeping out (from the primary circuit) of fission products released from the fuel during the core heatup. There is also no significant variation in the results when the opening size is >33 cm2, and only a slight sensitivity is found when the rupture size is between 3.3 and 33 cm2. The fission product release decreases considerably in the range from 1 to 3.3 cm2. The smallsized rupture is of major significance, as the failure of the relief valves to reclose increases the frequency of the event. In addition, the highest core temperature in the most severe depressurization accident scenario is evaluated, and its calculated value is lower than the graphite sublimation temperature. Although the simulation closely follows the German HTR-500 design, the conclusions may be applied to the general concept of the medium-sized high-temperature gas reactor.