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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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Latest News
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.
Ashok Kumar, Feroz Ahmed, L. S. Kothari
Nuclear Science and Engineering | Volume 67 | Number 1 | July 1978 | Pages 120-129
Technical Note | doi.org/10.13182/NSE78-A27242
Articles are hosted by Taylor and Francis Online.
Using multigroup diffusion theory with energy-dependent boundary conditions, the propagation of thermal-neutron waves has been studied in finite assemblies of beryllium and beryllium oxide. At different frequencies, we have calculated α and ξ for the discrete (or pseudo-discrete) mode as well as effective values of α(z) and ξ(z) (which include the effect of the source and higher modes) at a distance, z, from the source plane. In the case of beryllium, the results are in agreement with experimental findings of Miles et al. As observed by Miles et al., we find oscillations in the calculated values of α(z) and ξ(z) in a certain distance range beyond a certain frequency, which decreases with the decrease of transverse size of the assembly. Furthermore, in conformity with the experimental results of Miles et al., we find that with a decrease in the transverse dimensions of the assembly, the oscillations become larger, until one goes to very small assemblies, where these oscillations tend to smooth out. In the case of beryllium oxide, since no agreed value of Debye temperature exists and since the energy distribution of source neutrons is not known, only a qualitative comparison with the experimental results of Ritchie and Whittlestone has been possible.