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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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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.
W. Pfeiffer, J. R. Brown, A. C. Marshall
Nuclear Technology | Volume 27 | Number 3 | November 1975 | Pages 352-375
Technical Paper | Reactor | doi.org/10.13182/NT75-A24310
Articles are hosted by Taylor and Francis Online.
Pulsed-neutron experiments were performed on the 330-MW Fort St. Vrain high-temperature gas-cooled reactor (HTGR) to determine the reactivity of the core for various control rod configurations while the reactor was still subcritical. For all configurations the reactivity was inferred from the in-hour equation using the measured decay constant and a calculated generation time. For the configurations near critical, both the reactivity and generation time were determined using the extrapolated area-ratio method. The originally calculated (i.e., predicted) reactivities agreed poorly with those inferred from the experiments. However, by adding 5 ppm of boron to the reflector calculational model, the calculated generation time was significantly reduced. This brought the inferred reactivity into good agreement with that calculated for all control rod configurations. This emphasizes the dependence of the interpretation of pulsed-neutron experiments on calculations and the importance of the reflector in a large HTGR. Novel aspects of these experiments included the following: extensive two-dimensional computer simulations were performed prior to the experiments to determine the optimum source and detector locations; the neutron generation time was measured near critical by pulsing two different control rod configurations; all the data were fit by least squares to a sum of exponentials corresponding to one or two prompt modes and six delayed sub-modes; and an objective procedure using “tornado plots ” was developed to determine the starting channel for the least-squares analysis.