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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
Drew E. Kornreich
Nuclear Science and Engineering | Volume 115 | Number 1 | September 1993 | Pages 50-61
Technical Paper | doi.org/10.13182/NSE93-1
Articles are hosted by Taylor and Francis Online.
Solutions of fissile materials are often encountered during spent-fuel reprocessing. To estimate the hazards from accidental criticalities in these solutions, models have been developed to understand better the dynamics involved. Accurate representation of reactivity feedback mechanisms is a crucial part of such models. Reactivity feedback from uniform volumetric solution expansion is studied. For faster transients, density redistribution may also occur because of a variation of nuclear energy as a function of position in the assembly. Neutronic spectral temperature reactivity effects are studied by creating temperature-dependent cross sections from ENDF/B-VI data. The volumetric and temperature reactivity feedback coefficients are determined for the CRAC, KEWB-5, SILENE, and SHEBA solution assemblies. Spectral temperature coefficients are also calculated for poisoned, unpoisoned, and reflected plutonium solutions. Feedback coefficients are seen to be functions of geometry and isotopic contents of the assemblies. Results for plutonium solutions agree with other calculations, which confirms the possibility of autocatalytic excursions in large, dilute solutions.