Open-tubular gas-liquid

Takagi, T., and Itabashi, Y. (1981) Occurrence of Mixtures of Geometrical Isomers of Conjugated Octadecatrienoic Acids in Some Seed Oils Analysis by Open-Tubular Gas Liquid Chromatography and High Performance Liquid Chromatography, Lipids 16,546-551. 

Octadecatrienoic Acids in Some Seed Oils Analysis by Open-Tubular Gas Liquid Chromatography and High Performance Liquid Chromatography. 16 546—52... 

Application of the Design Equations to Packed Liquid Chromatography Columns and Open Tubular Gas Chromatography Columns... 

Figure 22-4 Resolution of 22 18-carbon fatty acid methyl esters with 1, 2, or 3 double bonds. Fatty acids shown in Figure 5-3 are labeled (peaks 3, 7, and 14). A Supelco ILIOO ionic liquid wall-coated open tubular gas chromatography column (100 m X 0.25 mm inner diameter with 0.20 xrr film thickness) was operated at 150°C with H2 carrier gas at a linear flow rate of 25 cm/s and flame ionization detection. [From C. Ragonese, P. Q. Tranchida, P. Dugo,...

The initial theoretical work on open-tubular gas chromatography (Golay) and on packed-column liquid chromatography (van Deemter) was published as early as the 1950s. These papers led to the development of commercial gas chromatographs using capillaries with micrometer diameters, and liquid chromatographs with micrometer-scale particles for the stationary phase. 

H. G. J. Mol, J. Staniewski, H.-G. Janssen and C. A. Cramers, Use of an open-tubular Capping column as phase-switching interface in on-line coupled reversed-phase liquid clir omatography-capillar y gas clir omatography , 7. Chromatogr. 630 201-212 (1993). 

Before discussing column preparation procedures a few comments on nomenclature are in order. Open tubular columns are also widely known as capillary columns. The characteristic feature of these columns is their openness, which provides an unrestricted gas path through the column. Thus open tubular colximn rather than capillary column is a more apt description. However, both descriptions appear frequently in the literature and can be emsidered interchangeable. The type of columns discussed so far are also known as wall-coated open tubular columns (WCOT). Here the liquid phase is deposited directly onto the column wall without the inclusion of any additive that might be considered as... 

Virtually all current research in SFC utilizes either small bore packed columns with particles of 5-10 micrometers in diameter optimized for use in liquid chromatography or narrow bore, fused silica open tubular columns with Immobilized phases similar to those used in gas chromatography. In the latter case columns of saaller internal diameter, 10-100 micrometers, shorter lengths (generally less than 20 m with 1-10 m being the most common length), and more firmly crosslinked stationary phases are used by coaparison with standard columns for gas chromatography. In all... 

The selection of the column type is mainly determined by the composition of the sample. In general open-tubular (capillary) columns are preferred for low-density (gas-like) SFC, whereas packed columns are most useful for high-density (liquid-like) SFC. Open-tubular columns can provide a much larger number of theoretical plates than packed columns for the same pressure drop. Volumetric flow-rates are much higher in packed column SFC (pSFC) than in open-tubular column SFC (cSFC), which makes injection and flow control less problematic. 

Support coated open tubular (SCOT) columns, 4 615 6 379 Supported liquid membranes, 16 28 Support material, in fluidized-bed encapsulation, 11 540 affinity chromatography, 6 392-393 chromatography, 6 375 gas chromatography, 6 375 Supported metals... 

Henry s Law constant for the equilibrium is KH = (Vc/Vg)((t/to) — 1). Vc and Vg are the volumes of condensed and vapor phases in the column (i.e. for gas-liquid chromatography, Vc is the volume of the liquid film on the supported packing or open tubular wall, and Vg the volume of void space, respectively). If the column is in the linear range (small loading) the resolution is,... 

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