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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.
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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.
Peter M. Song, Mahmoud Z. Youssef, Mohamed A. Abdou
Nuclear Science and Engineering | Volume 113 | Number 4 | April 1993 | Pages 339-366
Technical Paper | doi.org/10.13182/NSE93-A15333
Articles are hosted by Taylor and Francis Online.
A new approach for treating the sensitivity and uncertainty in the secondary energy distribution (SED) and the secondary angular distribution (SAD) has been developed, and the existing two-dimensional sensitivity/uncertainty analysis code, FORSS, was expanded to incorporate the new approach. The calculational algorithm was applied to the 9Be(n,2n) cross section to study the effect of the current uncertainties in the SED and SAD of neutrons emitted from this reaction on the prediction accuracy of the tritium production rate from 6Li (T6) and 7Li (T7) in an engineering-oriented fusion integral experiment of the U.S. Department of Energy/Japan Atomic Energy Research Institute Collaborative Program on Fusion Neutronics in which beryllium was used as a neutron multiplier. In addition, the analysis was extended to include the uncertainties in the integrated smooth cross sections of beryllium and other materials that constituted the test assembly used in the experiment. This comprehensive two-dimensional cross-section sensitivity/uncertainty analysis aimed at identifying the sources of discrepancies between calculated and measured values for T6 and T7. Without considering the uncertainties in the SED and SAD of the 9Be(n,2n) cross section, the uncertainties in T6 are ∼2 to 3% in the Li2O breeding zone, whereas they are ∼10% when the uncertainties in the SED and SAD are included. The contribution from the uncertainties in the SAD was small (∼1%) compared with the contribution from the uncertainties in the SED. As for T7, the uncertainties in the Li2O zone with and without considering the SED and SAD results are 4 to 7 and 2 to 5.5%, respectively. The estimated uncertainties in T6 and T7 could partly cover the observed discrepancies between calculations and measurements, although other sources have been identified. Although the approach followed to complete the uncertainty analysis is not standard because of the absence of an existing file that contains the uncertainty information in the SED and SAD of the 9Be(n,2n) reaction, the results obtained by introducing approximations to these data clearly demonstrate the importance of accounting for the uncertainties in the SED and SAD when a complete cross-section sensitivity/uncertainty analysis is to be performed.
