Aluminum-clad fused-silica capillary

Aluminum-Clad Fused-Silica Capillary Columns... 

A third type of protective outer coating, stainless steel, for fused silica offers an alternative to aluminum-clad fused silica for elevated column temperatures. This technology is the inverse of that for polyimide-clad fused-silica capillary where a layer of fused silica is deposited on the inner surface of a stainless capillary. In Figure 3.19 scanning electron micrographs are displayed to compare the rough surface of stainless steel with the smooth surface of untreated fused silica and the surface of stainless steel after a micron meter layer of deactivated fused silica... 

FIGURE 3.20 Photographs of metal-clad capillary columns (a) aluminum-clad capillary column (photograph courtesy of the Quadrex Corp.) (b) fused-silica-lined stain-less-steel capillary column (lower) and polyimide-clad fused-silica capillary columns (upper) photographs courtesy of the Restek Corporation. 

Figure 1.2 Various columns and materials employed for capillary gas chromatography (a) left 25 m x in. o.d. stainless steel capillary column in a pancake format, center 30 m X 0.25 mm i.d. aluminum-clad fused-silica column, right blank or uncoated stainless steel capillary tubing o.d. (b) 60 m x 0.75 mm i.d. borosilicate glass capillary column for EPA method 502.2 (c) 30 m x 0.25 mm i.d. fused-silica capillary column also pictured is a typical cage used to confine and mount a fused-silica column.

LtPSKY, S. R. Duffy, M. L. 1986a. High temperature gas chromatography the development of new aluminum clad flexible fused silica glass capillary columns coated with thermostable nonpolar phases Part 1. Journal of High Resolution Chromatography, 9, 376-382. 

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