Whisker-walled columns

The Golay equation is strictly applicable to open tubular columns with smooth walls but, with certain approximations, it can be extended to include support-coated (77) and whisker-walled (78)... 

A fourth type of column is the whisker walled (WW) in which the wall of the column has been etched by chemical means, leaving behind whiskers on the surface of the column. These projections of the fused silica significantly increase the available surface area of the column. Wall-coated, porous-layer, and support-coated capillary columns have all been available as whisker walled and have been given the acronyms WWCOT, WWPLOT, and WWSCOT, respectively. 

Open tubular columns are simply capillary tubes in which the inside of the column wall is used as the support for the liquid phase. These wall-coated open tubular columns (WCOT) have the stationary phase distributed in the form of a thin film on the inside surface of the open capillary tube, the walls thus serving as the support. In order to reduce the thickness of the liquid phase film, a porous layer may be formed on the inside wall of the capillary tubing and then coated with the liquid phase to produce a support-coated open tubular column (SCOT). Porous-layer open tubular colunms (PLOT) are similar to SCOT colunms, the difference being that in the former, the stationary phase is deposited on fine crystalline particles or glass powder which is adsorbed onto the walls of the tube. In both cases, the available surface area of the wall is increased, and allows an increased amount of liquid phase to be accommodated in the same length and diameter of tubing. The whisker-walled (WW) colunm consists of whiskers chemically etched on the surface of the wall, which also result in a significant increase in the available surface area. Wall-coated, porous-layer, and support-coated capillary columns are all available as whisker-walled, i.e., WWCOT, WWPLOT, and WWSCOT, respectively. 

WWCOT. A whisker-wall-coated open tubular column. It is a WCOT in which the walls have been etched before the stationary phase is deposited. 

WWCOT Whisker-wall-coated open tubular (column) WWPLOT Whisker-wall porous-layer open tubular (column) XRD X-ray diffraction... 

WWCOT whisker-wall coated open tubular (column) V frequency... 

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