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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.
Gary R. Smolen, Raymond C. Lloyd, Tomozo Koyama
Nuclear Technology | Volume 107 | Number 3 | September 1994 | Pages 326-339
Technical Paper | Nuclear Criticality Safety | doi.org/10.13182/NT94-A35011
Articles are hosted by Taylor and Francis Online.
Critical experiments were performed at the Pacific Northwest Laboratory-Critical Mass Laboratory from 1985 to 1987 with mixed Pu+U nitrate solutions in annular geometry. The 25.4-cm-diam central region of the annular vessel contained various inserts, such as a bottle containing fissile solution and borated-concrete and cadmium-covered polyethylene annular inserts. The fissile solution concentrations ranged from 47 to 226g Pu/ℓ with Pu/Pu+U ratios of 1.0, 0.5, and 0.2. The criticality data were used to validate two versions of the SCALE computer code system (SCALE-4 and SCALE-2). The analyses were performed with the 27-energy-group cross-section library, derived from the Evaluated Nuclear Data File B-Version IV. Computer models were prepared to accurately simulate all significant materials that would affect the system reactivity. The average calculated keff for the 18 experiments was 1.008 (σ = 0.006) with SCALE-4 and 1.004 (σ = 0.006) with SCALE-2. Overall, the range of calculated keff’s varied from 0.990 to 1.017. The results of the validation calculations indicate that the SCALE computer code system is capable of accurately modeling Pu+U nitrate. solutions in annular geometry.