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Journal of Radioanalytical and Nuclear Chemistry
Authors: P. Wilk, J. Landrum, D. Shaughnessy, J. Kenneally, N. Stoyer, M. Stoyer, K. Moody, N. Aksenov, G. Bozhikov, E. Tereshatov, G. Vostokin, S. Shishkin, and S. Dmitriev

Abstract  

A chemical separation method based on reversed-phase chromatography has been developed to separate the group five elements from the reaction products produced in the bombardment of 243Am with 48Ca ions. Decontamination factors on the order of 106 were achieved for group-three elements such as americium, and 107 or more for selected reaction products as measured by gamma-ray spectrometry pre-and post-chemistry. Details of the chemical separation scheme are discussed and compared to previously reported results.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: J. McAninch, A. Marchetti, B. Bergquist, N. Stoyer, G. Nimz, M. Caffee, R. Finkel, K. Moody, E. Sideras-Haddad, B. Buchholz, B. Esser, and I. Proctor

Abstract  

Accelerator mass spectrometry (AMS) is an established technique for the detection of long-lived radionuclides at environmental levels. At LLNL, planned facility upgrades and advances in detection techniques are allowing us to explore the applicability of AMS to isotopes not previously pursued. One such isotope is99Tc. We have performed a number of preliminary tests to examine the technical feasibility of AMS for the detection of99Tc. The questions addressed were negative ion production in the cesium sputter source, transport efficiency for the ions through the spectrometer, and detection efficiency for99Tc ions after the spectrometer. Based on the positive results of these tests, we have begun to develo measurement protocol.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: B. Wierczinski, K. Gregorich, B. Kadkhodayan, D. Lee, L. Beauvais, M. Hendricks, C. Kacher, M. Lane, D. Keeney-Shaughnessy, N. Stoyer, D. Strellis, E. Sylwester, P. Wilk, D. Hoffman, R. Malmbeck, G. Skarnemark, J. Alstad, J. Omtvedt, K. Eberhardt, M. Mendel, A. Nähler, and N. Trautmann

Abstract  

Subsecond 224 Pa (T 1/2 = 0.85 s) was produced via the 209 Bi(18 O,3n)224 Pa reaction at the 88 inch cyclotron at the Lawrence Berkeley National Laboratory. After production it was transported via a gas-jet system to the centrifuge system SISAK 3. Following on-line extraction with trioctylamine/scintillation solutions from 1M lactic acid, 224 Pa was detected applying on-line -liquid scintillation counting. Unambiguous identification was achieved using time-correlated --decay chain analysis. This constitutes the first chemical on-line separation and detection of a subsecond -decaying nuclide, 0.85-s 224 Pa with the fast extraction system SISAK 3.

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