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Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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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
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.
Garry C. Gose, Thomas J. Downar, Karl O. Ott
Nuclear Technology | Volume 124 | Number 3 | December 1998 | Pages 284-290
Technical Note | Reactor Safety | doi.org/10.13182/NT98-A2927
Articles are hosted by Taylor and Francis Online.
The main-steam-line-break (MSLB) transient in a pressurized water reactor (PWR) is a core overcooling event that can result in a large positive reactivity insertion. In most analyses the shutdown margin is sufficiently large that the core does not return to critical. However, some researchers have reported an increase in the core power even though the core does not return to critical. A simplified kinetics model based on the prompt-jump-kinetics approximation is reported in new work, and a single delayed neutron group is used to explain the core power increase during subcriticality. Specifically, it is shown that the multiplication of the initial delayed-neutron source as predicted by the rate of change of the reactivity during the transient is the reason for the increase in power even though the core never returns to criticality after scram. The results are demonstrated using data from a RETRAN-03 model of a hot-zero-power MSLB analysis of the Three Mile Island unit 1 PWR.