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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
Meeting Spotlight
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
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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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.
C. H. Reed, C. N. Henry, A. A. Usner
Nuclear Science and Engineering | Volume 30 | Number 3 | December 1967 | Pages 362-373
Technical Paper | doi.org/10.13182/NSE67-A18399
Articles are hosted by Taylor and Francis Online.
Asymptotic decay constants for pulse-induced “thermalized” neutron fields have been measured for graphite cubical assemblies having geometric bucklings varying from 9.30 × 10–4 cm–2 to 13.44 × 10–3 cm–2. A value of 700 μ sec was observed to be a sufficient time after the neutron pulse to identify and evaluate fundamental-mode decay in the smallest system included in the above interval of buckling. Values of the infinite-medium neutron lifetime –1 “Fick’slaw” diffusion coefficient D0, as well as the so-called “diffusion-cooling” coefficient C, were obtained from least-squares fits to the experimental α/ρ vs B2/ρ2 data and are mutually consistent and stable over a large interval of B2 and in good agreement with theory. The existence of a well-defined negative FB6 term has been verified. An “effective” higher-mode decay of (3570 ± 80)sec–1, independent of system buckling, was obtained and is consistent with the concept of a continuum lying above a critical limit for fundamental-mode decay. An apparent critical limit (v ∑ t)min has been identified in the interval 2392 sec–1 < (v ∑ t)min < 2648 sec–1 which corresponds to the interval of buckling 13.44 × 10–3 cm–2 to 16.53 × 10–3 cm–2.