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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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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Weston M. Stacey, Jr.
Nuclear Science and Engineering | Volume 29 | Number 2 | August 1967 | Pages 254-263
Technical Paper | doi.org/10.13182/NSE67-A18535
Articles are hosted by Taylor and Francis Online.
Analytical expressions for the spatially independent spectrum and importance (adjoint) function in fast-reactor assemblies have been developed. These expressions were obtained by solving the neutron balance equation, and the equation adjoint thereto, by the method of successive approximation. Solutions obtained in this manner suggest an interpretation of the collision density in terms of the probability that a fission neutron suffers a given sequence of scattering collisions, summed over all such sequences. Similarly, the importance function is interpreted in terms of the fission-neutron production probability following a given sequence of scattering collisions, summed over all such sequences. The analytical expressions are readily evaluated using either differential or group-averaged cross-section values. Integral properties of highly enriched and dilute fast-reactor assemblies were evaluated and compared with experiment; the agreement was comparable with that obtained with multigroup calculations normally employed to evaluate such assemblies.