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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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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Latest News
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.”
Charlotte Sandrin, Richard Sanchez, Florence Dolci
Nuclear Science and Engineering | Volume 168 | Number 1 | May 2011 | Pages 59-72
Technical Paper | doi.org/10.13182/NSE10-44
Articles are hosted by Taylor and Francis Online.
Today's reactor core calculations are done in diffusion with a few coarse groups and require the homogenization of the core assemblies as well as a correct representation of the reflector. In industrial applications a homogeneous reflector is often used with cross sections obtained from transport calculations and adjusted to fit in-core measurements. However, the need for better precision in the core diffusion calculations and the emergence of new reflector concepts, such as for the European Pressurized Reactor (EPR), require an increase in the number of coarse groups for novel loading patterns and a rethinking of how to define the equivalent reflector. In this work we analyze and extend current techniques for the reflector homogenization for core calculations. Following the adopted industrial methodology, we have perfected a technique for the determination of an equivalent homogenous reflector by implementing a Particle Swarm Optimization Algorithm and showed its limitations through the analysis of an academic slab reactor model and of a realistic two-dimensional representation of the EPR. We have compared the precision of the resulting core calculations to transport reference calculations as well as to diffusion calculations using a multigroup albedo boundary condition. We have also explored the use of current-preserving flux discontinuity coefficients at the core-reflector interface in conjunction with an equivalent reflector.