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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
Standards Program
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.”
Bernhard Kienzler, Andreas Loida, Werner Maschek, Andrei Rineiski
Nuclear Technology | Volume 143 | Number 3 | September 2003 | Pages 309-321
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT03-A3419
Articles are hosted by Taylor and Francis Online.
In an underground repository for spent fuel, criticality is excluded initially by compliance with the disposal conditions. In the long term, critical accumulations of fissile material can be formed only by mobilization of uranium and plutonium from the waste forms and subsequent precipitation or sorption of these elements. This paper presents an overview of mechanisms relevant for mobilization and possible accumulation of U and Pu from disposed mixed-oxide fuel elements. Concentrations of fissile materials observed in laboratory corrosion experiments together with model approaches are applied to determine the degree of fissile material accumulation and the risk of a sustained nuclear chain reaction. A prerequisite of criticality in a repository is an accumulation of fissile materials. Since geometry, moderation, and neutron absorption properties cannot be forecast, the neutron multiplication factor kinf is used (instead of keff) as a measure of the incidence of criticality. The factor kinf is derived for several scenarios. Required critical masses and critical volumes are evaluated.The accumulation of Pu onto solids is considered, and it is shown how selective enrichment of Pu and U may affect the risk of criticality. It is also shown that the criterion for criticality would be met only in the unrealistic case of selective sorption of 239Pu. Realistic sorption densities are too low to provide sufficient accumulation of fissile materials for criticality. This is particularly true if high Cl concentrations are present.