Patent ID: 6952946
Filing Date: 2005-10-11
Classification: G01N

Abstract:
1. A method of gas chromatographic analysis of a dosed sample, comprising: passing the sample through a separation device and thereby separating components contained in the sample, detecting selected components of the sample at an end of the separation device with a detector and quantitatively determining the selected components in accordance with a detector signal supplied by the detector, detecting the sample nondestructively upstream from the separation device with an additional detector and quantitatively determining the sample in accordance with an additional detector signal supplied by the additional detector, and verifying the analysis with the quantitative determination of the samples, wherein the additional detector comprises a thermal conductivity detector, and wherein the thermal conductivity detector functions alternately as the detector and as the additional detector, the thermal conductivity detector includes a bridge circuit, two diagonally opposed heating resistors in the bridge circuit are situated in the two different bridge halves in a measurement path of the detector, two further heating resistors in the bridge circuit are situated in a measurement path of the additional detector, and the sample flows through only one of the two measurement paths at any given time.