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Isotopes & Radiation
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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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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.”
K. L. Thomsen
Nuclear Science and Engineering | Volume 119 | Number 3 | March 1995 | Pages 167-174
Technical Paper | doi.org/10.13182/NSE95-A24082
Articles are hosted by Taylor and Francis Online.
The coupled collision probability and interface-current equations in the flat-flux, isotropic approximation are implemented in a light water reactor (LWR) lattice code that is under development. By using traditional Gaussian elimination of the subregion fluxes of the cells, the interface-current equations are turned into a nodal form. In the transformed flux and current equations, expressed in terms of response matrix theory, the coefficients become multiple-flight probabilities, which obey analogous conservation and reciprocity relations as the first-flight probabilities. The convergence of the iterative solution for the interface currents is accelerated by successive overrelaxation (SOR) and global rebalancing techniques. The improvement of the convergence rate is investigated in a series of test calculations. The optimal strategy is found to be alternation between one SOR iteration and three to four free iterations while the rebalancing should be limited to two initial iterations in normal LWR cases.