UPCOMING RESEARCH Application of a Trochoidal Electron Monochromator/Mass Spectrometer System to the Study of Environmental Chemicals
Cloud Point Preconcentration and High-Performance Liquid Chromatographic Analysis with Electrochemical Detection
Monoenergetic electrons are used to improve the quality of mass spectra from environmental chemicals by eliminating well-known artifacts. M~ and 1 3 C(M-H)~ species are resolved on an energy basis. J. A. Laramée, C. A. Kocher, and M. L. Deinzer*, Department of Agricultural Chemistry, Environmental Health Sciences Center, and Department of Physics, Oregon State University, Corvallis, OR 97331
Because transparent surfactants a r e not commercially available, cloud point preconcentration w i t h Triton X-114 is used followed by HPLC analysis with electrochemical detection. Carmelo Garcia Pinto, José Luis Perez Pavon, and Bernardo Moreno Cordero*, Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Quimica, Universidad de Salamanca, 37008 Salamanca, Spain
Comparison of One- and Two-Color Ionization Schemes for the Analysis of Osmium and Rhenium Isotopic Ratios by Sputter-Induced Resonance Ionization Mass Spectrometry
High Resolution Determination of 147 Pm in Urine Using Dynamic Ion-Exchange Chromatography
A two-color scheme is investigated as a means of increasing the ionization signal. Isotope ratio measurements of Re filaments show more sample-to-sample variations because of varying conditions of the laser beams a n d a higher bias t h a n do corresponding analyses of loaded samples. Jonathan England*, Laurie Reisberg, Franco Marcantonio, and Alan Zindler, Lamont-Doherty Geological Observatory of Columbia University, Palisades, NY 10964 Collection Efficiency of Solid Surface and Sorbent Traps in Supercritical Fluid Extraction with Modified Carbon Dioxide Solid-phase trapping efficiency in off-line SFE as a function of methanol modifier concentration and trap temperature is studied. ODS traps better t h a n stainless steel with modified fluids. Trap temperature greatly influences collection efficiency. With high (> 4%) methanol concentrations, neither trap is satisfactory. L. J. Mulcahey and L. T. Taylor*, Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 Steady-State Voltammetry of Strong and Weak Acids with and without Supporting Electrolyte
Rare-earth radionuclides in bioassay samples a r e preconcentrated by cation exchange and separated by dynamic ion exchange. Liquid scintillation detection of the 147 Pm fraction yields a detection limit of 3 fg. Steve Elchuk, Charles A. Lucy*, and Kerry I. Burns, AECL Research, General Chemistry Branch, Chalk River Laboratories, Chalk River, Ontario, Canada KOJ 1J0 Flow Determination of Dissolved Inorganic Carbon Using the Alternate Washing System Equipped with a Potentiometric Gas Electrode At pH 5, dissolved inorganic carbon is determined with less interference from nitrite, sulfide, a n d hydrogen sulfite than a t pH 2. Hirokazu Hara*, Yohzoh Okabe, and Tomoko Kitagawa, Department of Chemistry, Faculty of Education, Shiga University, Otsu, Shiga 520, Japan Analysis of Phosphite Polymer Stabilizers by Laser Desorption/Electron Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Abundant molecular ions of phosphite and phosphate additives are detected a t —0.1% in a solid polymer by laser desorption/electron ionization FTICR MS. Xinzhen Xiang, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, OH 43210, James Dahlgren and William P. Enlow, General Electric Company, Parkersburg Center, Fifth and Avery Streets, Parkersburg, WV 26102, and Alan G. Marshall*, Departments of Chemistry and Biochemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, OH 43210
Steady-state voltammetry at microelectrodes enables the voltammetric determination of undissociated weak acids in t h e presence and absence of supporting electrolyte. Linear calibration curves are also found for proton reduction in solution of strong acids. Malgorzata Ciszkowska and Zbigniew Stojek, Department of Chemistry, University of Warsaw, ul. Pasteura 1, 02-093 Warsaw, Poland and Susan E. Morris and Janet G. Osteryoung*, Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204
Theory of the Interfacial Potential Distribution and Reversible Voltammetric Response of Electrodes Coated with Electroactive Molecular Films
These articles are scheduled to appear in AC RESEARCH in the n e a r future. ""Corresponding author
Nonideal cyclic voltammetric waveshapes observed in the response of electrodes coated with electroactive molecular films are analyzed using a model of the interfacial potential distribution. Christopher P. Smith and Henry S. White*, Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455 ANALYTICAL CHEMISTRY, VOL. 64, NO. 19, OCTOBER 1, 1992 · 911 A
