Preface. Acknowledgments. 1 Introduction. 1.1 Evolution of Gas Chromatographic Columns. 1.2 Central Role Played by the Column. 1.3 Justification for Column Selection and Care. 1.4 Literature on Gas Chromatographic Columns. 1.5 Gas Chromatographic Resources on the Internet. References. 2 Packed Column Gas Chromatography. 2.1 Introduction. 2.2 Solid Supports and Adsorbents. Supports for Gas-Liquid Chromatography. Adsorbents for Gas-Solid Chromatography. 2.3 Stationary Phases. Requirements of a Stationary Phase. USP Designation of Stationary Phases. Kovats Retention Index. McReynolds and Rohrschneider Classifications of Stationary Phases. Evaluation of Column Operation. Optimization of Packed Column Separations. 2.4 Column Preparation. Coating Methods. Tubing Materials and Dimensions. Glass Wool Plugs and Column Fittings. Filling the Column. Conditioning the Column and Column Care. 2.5 United States Pharmacopeia and National Formulary Chromatographic Methods. References. 3 Capillary Column Gas Chromatography. 3.1 Introduction. Significance and Impact of Capillary Gas Chromatography. Chronology of Achievements in Capillary Gas Chromatography. Comparison of Packed and Capillary Columns. 3.2 Capillary Column Technology. Capillary Column Materials. Fused Silica and Other Glasses. Extrusion of a Fused-Silica Capillary Column. Aluminum-Clad Fused-Silica Capillary Columns. Fused-Silica-Lined Stainless Steel Capillary Columns. 3.3 Preparation of Fused-Silica Capillary Columns. Silanol Deactivation Procedures. Static Coating of Capillary Columns. Capillary Cages. Test Mixtures for Monitoring Column Performance. Diagnostic Role Played by Components of Test Mixtures. 3.4 Chromatographic Performance of Capillary Columns. Golay Equation Versus the van Deemter Expression. Choice of Carrier Gas. Measurement of Linear Velocity and Flow Rate. Effect of Carrier Gas Viscosity on Linear Velocity. Phase Ratio. Coating Efficiency. 3.5 Stationary-Phase Selection for Capillary Gas Chromatography. Requirements. History. Comparison of Columns from Manufacturers. Polysiloxane Phases. Polyethylene Glycol Phases. Cross-Linked Versus Chemically Bonded Phase. Chemical Bonding. MS-Grade Phases Versus Polysilarylene or Polysilphenylene Phases. Sol-Gel Stationary Phases. Phenylpolycarborane-Siloxane Phases. 3.6 Specialty Columns. EPA Methods. Chiral Stationary Phases. Gas-Solid Adsorption Capillary Columns: PLOT Columns. 3.7 Capillary Column Selection. Practical Considerations of Column Diameter, Film Thickness, and Column Length. Capillary Columns of 0.53mm i.d.: Megabore Columns. Correlation of Column Dimensions and Film Thickness with Parameters in the Fundamental Resolution Equation. Column Selection for Gas Chromatography by Specifications. 3.8 Column Installation and Care. Carrier Gas Purifiers. Ferrule Materials and Fittings. Column Installation. Column Conditioning. Column Bleed. Retention Gap and Guard Columns. Column Fatigue and Regeneration. 3.9 Special Gas Chromatographic Techniques. Simulated Distillation. Multidimensional Gas Chromatography. Computer Modeling of Stationary Phases. References. 4 Column Oven Temperature Control. 4.1 Thermal Performance Variables and Electronic Considerations. 4.2 Advantages of Temperature Programming over Isothermal Operation. 4.3 Oven Temperature Profiles for Programmed-Temperature Gas Chromatography. 4.4 Role of Computer Assistance in Optimizing Separations in Gas Chromatography. DryLab (LC Resources). ProezGC (Restek Corporation). GC-SOS (Chem SW). 4.5 Fast or High-Speed Gas Chromatography. Selectivity Tuning. Resistively Heated Columns and Column Jackets. 4.6 Subambient Oven Temperature Control. References. Selected References. Appendix A: Guide to Selection of Packed Columns. Appendix B: Column Selection. Index.

The Stephen Dal Nogare award is one of the oldest and most prestigious awards given in chromatography. Since 1972, it has been presented by the Chromatography Forum of the Delaware Valley, usually at the annual Pittsburgh Conference. Little has been written about Stephen Dal Nogare "the man" or his contributions to scientific knowledge, including his unique contributions to separations science. This paper describes his scientific career and how it has influenced the practice of chromatography.

This chapter contains sections titled: Introduction Capillary Column Technology Preparation of Fused-Silica Capillary Columns Chromatographic Performance of Capillary Columns Stationary-Phase Selection for Capillary Gas Chromatography Specialty Columns Capillary Column Selection Column Installation and Care Special Gas Chromatographic Techniques References

Free Access Appendix A: Guide to Selection of Packed Columns Eugene F. Barry Ph.D., Eugene F. Barry Ph.D. Professor of Chemistry University of Massachusetts Lowell, USASearch for more papers by this authorRobert L. Grob Ph.D., Robert L. Grob Ph.D. Professor Emeritus Analytical Chemistry, Villanova University, USASearch for more papers by this author Book Author(s):Eugene F. Barry Ph.D., Eugene F. Barry Ph.D. Professor of Chemistry University of Massachusetts Lowell, USASearch for more papers by this authorRobert L. Grob Ph.D., Robert L. Grob Ph.D. Professor Emeritus Analytical Chemistry, Villanova University, USASearch for more papers by this author First published: 07 August 2006 https://doi.org/10.1002/9780470114186.app1 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Columns for Gas Chromatography: Performance and Selection RelatedInformation

Free Access Appendix B: Column Selection Eugene F. Barry Ph.D., Eugene F. Barry Ph.D. Professor of Chemistry University of Massachusetts Lowell, USASearch for more papers by this authorRobert L. Grob Ph.D., Robert L. Grob Ph.D. Professor Emeritus Analytical Chemistry, Villanova University, USASearch for more papers by this author Book Author(s):Eugene F. Barry Ph.D., Eugene F. Barry Ph.D. Professor of Chemistry University of Massachusetts Lowell, USASearch for more papers by this authorRobert L. Grob Ph.D., Robert L. Grob Ph.D. Professor Emeritus Analytical Chemistry, Villanova University, USASearch for more papers by this author First published: 07 August 2006 https://doi.org/10.1002/9780470114186.app2 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Columns for Gas Chromatography: Performance and Selection RelatedInformation

This appendix discusses the effect of detector attenuation change and chart speed on peak height, peak width, and peak area. Examples and discussion are included.

This appendix features a list of useful hints for gas chromatography.

The extraction of the following primary aromatic amines from soil samples was studied: 1,4-phenylenediamine, 2,4-diaminotoluene, benzidine, 4,4'methylenebis(2-chloroaniline), 3,3'-dimethylbenzidine, and 3,3'-dichlorobenzidine. An extensive comparison of supercritical fluid extraction (SFE) with sonication extraction was performed. The SFE method yielded significantly higher recoveries and equivalent or better precision than sonication extraction for all eleven matrices studied. Characterization data for these matrices was evaluated to determine characteristics which affect primary aromatic amine recovery and to study the potential mechanisms involved in adsorption on the soil. It was determined that amine recovery was affected by the percent clay, the surface area, and the cation exchange capacity of the soil. Adsorption likely involves cation exchange groups including silanols on the surface of the clay materials in the soil.

The extraction of the following primary aromatic amines from aqueous samples was studied: 1,4-phenylenediamine, 2,4-diaminotoluene, benzidine, 4,4'-methylenebis(2-chloroaniline), 3,3'-dimethylbenzidine, and 3,3'-dichlorobehzidine. Five different adsorbents were evaluated for solid-phase extraction (SPE) in the reversed-phase mode. An SPE method utilizing a styrene/divinylbenzene copolymer disk was developed, and compared to separatory funnel and continuous liquid-liquid extraction techniques. significantly better recoveries were obtained on fortified tap, stream, and lake water samples using SPE.

Supercritical carbon dioxide mixed with 3% methanol was used to extract real-world soil samples fortified with 12 selected organophosphate and organochlorine pesticides. Comparison of replicate supercritical fluid extractions (N=3) to classical sonication extractions (N=3) showed equivalent recoveries of the pesticides from four soil samples. The precisions for sonication extraction and SFE were also demonstrated to be identical.

Supercritical carbon dioxide and carbon dioxide mixed with 3% methanol are used to extract various soils fortified with selected organophosphate and organochlorine pesticides to study the effects of supercritical fluid extraction (SFE) conditions and soil matrix variables on pesticide recoveries. Pesticide recoveries are shown to increase with increases in density and pressure. Temperature, however, is found to have little effect on the recoveries of most of the pesticides, although the thermal breakdown of endrin aldehyde at higher extraction temperatures is demonstrated. A static soak prior to dynamic removal seems to have little influence in speeding extraction rates. With the exception of a sand matrix, pure carbon dioxide alone Is unable to remove the polar pesticides from the fortified soils, although acceptable recoveries are achieved for the nonpolar organochlorine pesticides. When CO2 with 3% methanol is used, all of the pesticides are efficiently extracted from all of the soils and an overall average recovery of 94% is achieved. The SFE precision also improves, as demonstrated by an overall average RSD of 5% for methanol-modified CO2 compared to an RSD of 23% when pure CO2 is used. A small amount of moisture added to spiked top soil is found to behave like a modifier and increases polar pesticide recoveries when pure CO2 is used. When pH of the top soil is varied, best overall recovery of the pesticides are realized at near neutral pH (6.4). Lower SFE recoveries of some pesticides are observed at acidic and basic conditions because of either hydrolysis or protonation of the pesticides.

A comparison of extraction methods for primary aromatic amines including 1,4-phenylenediamine, 2,4-diaminotoluene, benzidine, 4,4'-methylenebis(2-chloroaniline), 3,3'-dimethylbenzidine, and 3,3'-dichlorobenzidine from solid matrices was conducted. Supercritical fluid extraction(SFE) was evaluated and compared with the classical method, sonication extraction. Poor recoveries and precision were obtained with sonication extraction, even on control sand, and factors affecting this poor performance were examined. Significantly better recoveries and precision were obtained on control sand using SFE with either supercritical carbon dioxide or nitrous oxide as solvent. The effect of sample matrix on both extraction methods was examined. The classical method as well as traditional approaches with SFE were ineffective in extracting four of the six compounds from soil. Nitrous oxide modified with 1,6-hexanediamine In methanol was utilized in SFE of soil, resulting in significant improvement for all analytes studied.