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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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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.”
Yutaka Takeuchi, Yukio Takigawa, Shiho Miyamoto
Nuclear Technology | Volume 128 | Number 2 | November 1999 | Pages 257-275
Technical Paper | Reactor Safety | doi.org/10.13182/NT99-A3030
Articles are hosted by Taylor and Francis Online.
A methodology for boiling water reactor (BWR) regional stability with a one-point neutron kinetics model is proposed from the higher harmonics viewpoint and is verified with the Ringhals-1 stability benchmark test data. A one-point neutron kinetics model for regional stability analysis is derived from the spatial neutron diffusion equation using the mode decomposition technique. From the derivation, the intermode coupled reactivity coefficient is defined and applied to a frequency-domain BWR stability analysis model. The analysis model traces a unit power perturbation and calculates the open-loop transfer function as the power response to the input perturbation. Combined with the aforementioned reactivity coefficient and the asymmetric shape perturbation that reflects the first azimuthal mode, the first azimuthal mode is excited exclusively without any assumption on the ex-core model. Therefore, the regional stability can be evaluated with a normal recirculation flow model, which is employed for core-wide stability analysis. The methodology is verified with the Ringhals-1 stability benchmark test data, whose stability conditions were widely distributed and suitable for verification. The results show that the proposed methodology is quite appropriate for BWR regional stability analysis.