an internal volume of 1.5 mL (328.9 cm length×0.762 mm i.d.;
TT as shown Figures 1-4). The six-port valve was connected to
the gas chromatograph by a silica capillary tube (74.6 cm length
×0.32 mm i.d., 60µL internal volume; CT in Figures 1-4). This
capillary was introduced into the glass-wool plug (7.7 mm from
the end of the ferrule). Since the six-port valve was positioned as
in Figure 1, when valve V1 was opened, the liquid from the CT
tubing was eliminated to waste.
The TOTAD interface (modified PTV injector) was placed
horizontally on the right-hand side of the gas chromatograph.
A standard glass insert (75 mm length×2 mm i.d.×4.5 mm
o.d.) was packed with 2 cm of Tenax TA and plugged at both
ends with silanized glass wool. The packed liner was conditioned
under a helium stream which was heated to 300°Cat50°C/min
and maintained for 5 min and then was programmed to 350°Cat
5°/min and maintained for 90 min at this temperature. The narrow