BRIEFS Qualitative Supercritical Fluid Chromatography/Fourier Transform Infrared Spectroscopy Study of Methylene Chloride and Supercritical Carbon Dioxide Extracts of Double-Base Propellant 145
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Contaminants in double-base propellants extracted with supercritical CO2 achieve better qualitative detection (using SFC/FT-IR) than contaminants extracted with methylene chloride. M. Ashraf-Khorassani and L. T. Taylor*, Department of Chem istry, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0212 Separation of Trace Metal Complexes for Analysis of Samples of High Salt Content by Inductively Coupled Plasma Mass Spectrometry 149 Analyte metals are retained on a resin column as neutral complexes with bis-(carboxymethyl)dithiocarbamate. Inter fering elements such as alkali metals, alkaline earth metals, and chloride are neither complexed nor retained so that analyte elements can be determined in urine and seawater with minimal matrix interference and little deposition of material on the sampling interface. Michael R. Plantz, James S. Fritz, Fred G. Smith, and R. S. Houk*, Ames Laboratory, U.S. Department of Energy, and Depart ment of Chemistry, Iowa State University, Ames, IA 50011 Evaluation of Pulsed Fast-Atom Bombardment Ionization for Increased Sensitivity of Tandem Mass Spectrometry 153 Improving the sensitivity of FAB ionization using a pulsed neutral beam is explored, and the results are compared with continuous FAB. The gains in sensitivity are demonstrated for tandem MS using collision-induced dissociation and photodissociation. R. E. Tecklenburg, Jr., M. E. Castro, and D. H. Russell*, De partment of Chemistry, Texas A&M University, College Station, TX 77840 Microhole Array for Oxygen Electrode
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A solid-state oxygen sensor is fabricated using the ultramicrohole/microelectrode array. The sensor has the advan tage of being moderately flow-rate-insensitive and discrimi native against macromolecular poisons. Ken-ichi Morita* and Yoshihiro Shimizu, Basic Research Lab oratories, Toray Ind., Inc., 1111 Tebiro, Kamakura-shi, Kanagawaken, 248 Japan Introduction of Liquid Samples into the Inductively Coupled Plasma by Direct Insertion on a Wire Loop 163 Detection limits in the picogram-to-subpicogram range are obtained for insertions of 10-μί, samples. The shape of the transient signal is significantly affected by matrix concen tration, but peak area remains constant. R. L. A. Sing and E. D. Salin*, Department of Chemistry, McGill University, Montreal, Quebec, H3A 2K6, Canada
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BRIEFS Hydrophobic Stripping Voltammetry Using a Lipid-Modified Glassy Carbon Electrode 170
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A lipid-modified glassy carbon electrode that selectively accumulates drugs is described. T h e antitumor drug marcellomycin is used to determine the affects of operating parameters. Olivier Chastel, Jean-Michel Kauffmann, and Gaston J. Patriarche*, Institut de Pharmacie, Université Libre de Bruxelles, Campus Plaine, CP 205/6 Boulevard du Triomphe, 1050 Bruxelles, Belgium and Gary D. Christian, Department of Chemistry, BG-10, University of Washington, Seattle, WA 98195-9550
Fiber-Optic Sensors Based on Reagent Delivery with Controlled-Release Polymers
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Two types of long-lasting fiber-optic sensors are p r e p a r e d based on r e a g e n t delivery with controlled-release polymers. Both sensors can m e a s u r e p H values between 5.5 and 8.0 with a precision better than ± 0 . 1 pH units. Shufang Luo and David R. Walt*, Max Tishler Laboratory for Organic Chemistry, Department of Chemistry, Tufts University, Medford, MA 02155
Conductometric Titrations of Polyprotic Acids in Nonaqueous Mixed Solvents. Effects of Temperature and Composition of the Solvent Mixture 177 The results indicate that the shape of the titration curve depends on the solvent physicochemical properties, the temperature, and the acid solute. Giancarlo Franchini, Andrea Marchetti, Carlo Preti, Lorenzo Tassi, and Giuseppe Tosi*, Department of Chemistry, University of Modena, Via G. Campi 183, 41100 Modena, Italy
Correspondence Chemical Ionization of Laser-Desorbed Neutrals in a Fourier Transform Mass Spectrometer 184 I. J. Amster, Donald P. Land, John C. Hemminger, and Robert T. Mclver, Jr.*, Department of Chemistry, University of California, Irvine, CA 92717
Technical Notes Modification of a High-Efficiency Passive Sampler To Determine Nitrogen Dioxide or Formaldehyde in Air
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James D. Mulik*, Robert G. Lewis, and William A. McClenny, Atmospheric Research and Exposure Assessment Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 and Dennis D. Williams, NSI Technology Services Corporation, Research Triangle Park, NC 27709
Thin-Layer Transmittance Cell for Infrared Spectroelectrochemistry
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Paul A. Flowers and Gleb Mamantov*, Department of Chemistry, University of Tennessee, Knoxville, TN 37996-1600
