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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
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.