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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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.”
Stephen M. Bajorek, Nikolay Petkov, Katsuhiro Ohkawa, Robert M. Kemper, Arthur P. Ginsberg
Nuclear Technology | Volume 136 | Number 1 | October 2001 | Pages 50-62
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT01-A3228
Articles are hosted by Taylor and Francis Online.
Since the 1988 Appendix K Rulemaking change, there has been significant interest in the development of codes and methodologies for "best-estimate" analysis of loss-of-coolant accidents (LOCAs). Most development has been directed toward large-break (LB) LOCAs (LBLOCAs), since for most pressurized water reactors (PWRs), the LBLOCA generates the limiting peak cladding temperature (PCT). As plants age, are uprated, and continue to seek improved operating efficiencies, the small break (SB) LOCA (SBLOCA) and intermediate-break (IB) LOCA (IBLOCA) can become a concern.Modifications have been made to the WCOBRA/TRAC-MOD7A code to enable it to make realistic calculations of SBLOCAs and IBLOCAs in a Westinghouse PWR. The MOD7A version has recently been approved for use as part of the Westinghouse best-estimate LOCA methodology for LBLOCAs. Thus, the modifications and improvements potentially allow LOCA calculations ranging from SBLOCAs to LBLOCAs using a single code version.The WCOBRA/TRAC-MOD7A, Rev. 4 SB02 version was used to calculate the transient response of a four-loop PWR for a range of break sizes located at the bottom of one of the cold legs. The break sizes ranged from a 0.051-m (2-in.) to a 0.406-m (16-in.) equivalent hole diameter. Each calculation was performed assuming American Nuclear Society (ANS) 1979 decay heat. The plant input assumed the loss of one train of safety injection as well as a power shape that was highly top skewed, which imposed some conservatism on the calculations but allowed a meaningful comparison to Appendix K-type analysis results. The realistic SBLOCA and IBLOCA results showed significantly reduced PCTs compared to those typically obtained from Appendix K LOCA calculations. The realistic results also can be categorized into four separate types of breaks, from a conventional slowly draining SBLOCA to an LBLOCA.