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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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.
Jack K. Thompson
Nuclear Technology | Volume 33 | Number 2 | April 1977 | Pages 235-236
Technical Note | Chemical Processing | doi.org/10.13182/NT77-A31781
Articles are hosted by Taylor and Francis Online.
Theoretical homogeneous plutonium-poly ethylene mixtures have significantly lower critical masses than theoretical homogeneous plutonium-water mixtures of comparable H/Pu ratio for H/Pu ratios close to optimum. The minimum critical mass for an optimally moderated, full water-reflected, homogeneous plutonium-poly ethylene mixture in spherical geometry has been calculated to be ∼360 g plutonium (±5% for cross-section uncertainties) compared to ∼530 g plutonium for a plutonium-water mixture under the same conditions. The 30% drop in critical mass is attributable to increased hydrogen atom density and the superior moderating characteristics of carbon over oxygen combined with a higher carbon atom density in polyethylene (ρ = 0.96 Mg/m3) than oxygen atom density in water (ρ = 1.0 Mg/m3).
