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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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.
E. A. Fischer
Nuclear Science and Engineering | Volume 62 | Number 1 | January 1977 | Pages 105-116
Technical Paper | doi.org/10.13182/NSE77-4
Articles are hosted by Taylor and Francis Online.
Integral measurements of delayed neutron fractions in fast reactor spectra by two different techniques were carried out. The worth of a calibrated 252Cf spontaneous fission source, together with absolute fission rates and with the normalization integral obtained from fission rate mapping, gives experimental values for the effective delayed neutron fraction of a critical assembly. These measurements were performed in three PUO2-UO2 fueled assemblies and in one UO2 fueled assembly. The pile oscillator technique was used to determine relative yields of delayed neutrons from 235U, 238U, and 239Pu. The results confirm the evaluated yields by Tuttle, with a slight bias toward a higher 239Pu yield. With these data, the central worth discrepancy disappears for SNEAK measurements.
