| 摘要 |
A headspace autosampling apparatus (92) for generating and delivering gaseous samples to a gas chromatograph or other instrument. The vials are delivered one at a time through a vial delivery mechanism (160) to a heated zone (146) wherein the substances (94, 96) to be analyzed reach equilibrium with the headspace (100, 102) above the samples in the vials. The vials are generally cylindrical and extend horizontally to facilitate attainment of equilibrium rapidly upon heating. The vials are also preferably rotated about their longitudinal axis prior to sampling so as to achieve a film effect on the interior walls of the vials which further aids in attainment of equilibrium. The apparatus is operative to first pressurize the headspace in the vial with an inert gas, and then to place said headspace in fluid communication with the inlet of a gas chromatograph wherein analyses in the headspace volume are analyzed to determine the composition thereof. One form of vial (260) operates to minimize changes in amounts of materials in the sample due to changes in equilibrium during sampling.
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