News
Tuesday Afternoon, June 2
DATA ACQUISITION, AND THEORY DETECTORS R. S. Juvet, Jr.,
HIGHEST PURITY DEUTERATED
NMR SOLVENTS WHY YOU CAN RELY ON ALDRICH’S GOLD LABEL SOLVENTS
Purity specifications of deuterated solvents for nuclear magnetic resonance spectroscopy are usually given in percentage of deuterium contained in the solvents, but one rarely finds information about the chemical purity of deuterated solvents. We have paid particular attention to both aspects of quality control in the preparation of our new solvent line. Aldrich’s deuterium purity is always given as atom per cent deuterium contained in the total molecule, as determined by nmr dilution experiments. Thus, our chloroform, at 99.8 atom per cent deuterium, contains less than two parts per thousand protonated chloroform, and our 99.5 per cent benzene-dó contains less than 5 protons per thousand
deuterons on the benzene ring. Since these materials are employed in nmr use, we routinely examine the entire nmr spectrum for proton-containing impurities and purify each solvent until extraneous proton-containing impurities are no longer detectable. The most common deuterated impurity is deuterium oxide, and we test for this impurity in a number of ways. Our dimethyl sulfoxide-d6, for example, is monitored by the method of Levenberg and Jeter [Analytical Chemistry, 38, 1971 (1966)] and contains less deuterium oxide than is contained in other commercially obtained dimethyl sulfoxide-d6 after drying for 96 hours over activated molecular sieve. Whether your primary interest is in isotopic purity or in chemical purity, we invite comparison of our solvents with any other solvents available. We assure you that solvents of higher purity cannot now be found.
A SAMPLING OF NEW PRODUCTS: 15,179-3 15.181- 5 15.182- 3 15,188-2 15,187-4
Acetone-cL (99.5% purity) Benzene-di (99.5% purity) Chloroform-d (99.8% purity) Deuterium oxide (99.8% purity) Dimethyl sulfoxide-d6 (99.5% purity)
15,194-7 Methyl alcohol-d« (99.5% purity) 15,232-3 Pyridine-ds (99% purity)
5 g. $13 10 g. $20 25 g. $45 10 g. $17 25 g. $35 50 g. $65 50 g. $12.50 10 g. $22 100 g. $17 5 g. $11 10 g. $19 25 g. $40
50 g. $69.50 5g. $60 10 g. $100 5g. $20 10 g. $35 25 g. $83
FOR THE COMPLETE LIST AND PRICES CONTACT YOUR NEAREST ALDRICH OFFICE.
ALDRICH CHEMICAL COMPANY, INC.
Main Office and Laboratories: 940 W. St. Paul Ave., Milwaukee, Wis. 53233; Dial 414 273-3850. San Leandro, California; 415 352-1186. Cedar Knolls, N.J.; 201 539-9494. Circle No.
72 A
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ANALYTICAL CHEMISTRY, VOL. 42, NO. 4, APRIL 1970
Presiding
2:00 Mathematical Treatment of GasChromatographic Data: Application to Tea Quality Evaluation. L. Vuataz and D. Reymond, Research Laboratories for Nestle's Products, Vevey, Switzerland 2:20 Computer Resolution of Unresolved Convoluted Gas Chromatographic Peaks. A. H. Anderson, T. C. Gibb, and A. B. Littlewood, School of Chemistry, The University, Newcastle-upon-Tyne, England 2:40 Multivariate Analysis of Chromatographic Data on Natural Mixtures. N. Hartmann and S. J. Hawkes, Oregon State University, Corvallis, Ore. 2:55 Utilization of Functional Group Retention Volume Indices in Qualitative Analysis. C. Merritt, Jr., J. T. Walsh, and J. Cavagnaro, U. S. Army Natick Laboratories, Natick, Mass. 3:10 Linear Electron Capture DetecD. C. Fenimore and C. M. tion. Davis, Texas Research Institute of Mental Sciences, Houston, Tex. 3:25 Chemi-lonization Detector, A Flameless Phosphorus Detector for Organo Phosphorus Pesticides. M. Scolnick, Varían Aerograph, Walnut Creek, Calif. 3:40 Response Characterjsitcs of Catalytic Ionization Detector to Organic Compounds of Varied Molecular . E. Umstead, F. J. Structure. Woods, J. E. Johnson, Naval Research Laboratory, Washington, D. C. 4:00 INTERMISSION 4:10 Retention Time and First Time Moment in Elution Chromatography. P. R. Rony and J. E. Funk, Monsanto Co., St. Louis, Mo., and University of Kentucky, Lexington, Ky. 4:30 Solution Thermodynamics and Separation Characteristics of Macromolecular Solvents. J. W. King and F. Covitz, Union Carbide Corp., Bound Brook, N. J. Time 4:50 Extent of Separation: Normalization and Minimum Time Analysis in Elution Chromatography. P. R. Rony, Monsanto Co., St. Louis, Mo.
Wednesday Morning, June 3
LIQUID CHROMATOGRAPHY H. Felton, Presiding
Errors 9:00 Measured Performance and Loss of Resolution in Liquid Chromatography. G. Deininger and I. Halász, Institut fiir physikalische Chemie der Universitaát, Frankfurt/ Main, Germany 9:30 Criteria for Choice of LiquidLiquid Systems in Chromatography. J. F. K. Huber, University of Amsterdam, Amsterdam, The Netherlands
