Abstract: A GC/IR system for analyzing the constituents of a gas sample is disclosed and claimed in which a floating light pipe assembly is disposed in a bore and troughs of a heater chamber in a heater assembly. The floating light pipe assembly has two transfer tubes and a light pipe tube that provide a completely chemically resistant path to the flow of a gas sample and carrier gas from a GC capillary column to a supplemental GC detector. The flow path is chemically inert since no contaminating sealants are used and substantially all of the flow path is gold plated. The light pipe assembly "floats" because it is allowed to thermally expand within the heater chamber so that high reflectivity in the IR region will be maintained as the light pipe assembly is being heated by the heater plates on opposite sides of the heater chamber.

Abstract: Effluent from an LC is passed through a thermospray nozzle which flash vaporizes substantially all of the solvent while directing any sample components as a collimated beam onto a moving tape so that the various components form spots on the tape. The tape is moved along a path that intercepts the optical path of an FTIR spectrometer whereby IR energy from the spectrometer is passed through each sample component and is then spectrally analyzed. The tape can be wound up, stored, and later used for further analysis of the spots, as desired, in the FTIR spectrometer.

Abstract: A gas chromatograph Fourier transform infrared (GC/FTIR) system includes a GC oven having a flexible capillary column therein for separating components of a sample. The column discharges effluent directly into a light pipe associated with an FTIR spectroscope. An auxiliary flow of carrier gas is added to the effluent at the light pipe to convey constituents through the light pipe free from tailing or peak broadening.