Abstract: A simplified, single component resin bed is coupled with a permeation tube and bottle. The permeation bottle contains an ionic species and a dissolved gas. The apparatus makes unnecessary a multi-component resin ion exchange column for solvent pH control in electrolytic conductivity detection as applied to gas chromatography.

Abstract: An improved photoionization detector has a sweep gas inlet which is used to introduce sweep gas near the window of the detector's ultraviolet lamp. The detector's chamber has a vent which allows selective removal of spurious analyte. The detector is adapted to have directly mounted on it, a second detector. Sweep gas used to keep analyte away from the window may be used as a reagent in the second detector. In addition, a means for regulating the ionization lamp voltage is disclosed which prolongs lamp life expectancy.

Abstract: A gas chromatograph system is provided with an improved electrolytic conductivity cell (16) for detecting a selected material species in a fluid stream from conventional gas chromatograph (10, 12) having both gas and liquid phases. Planar electrodes (80, 82) are spaced by an insulator (84) and define borehole diameters (88, 90, 92) which enhance the generated signal-to-noise ratio by providing a short fluid transit time within the conductivity detecting volume compared with the effective time of the chromatographic event of interest. A pneumatic damper (108) may be further included to reduce generated system signal noise.

Abstract: A gas chromatograph system is provided with an improved electrolytic conductivity cell (16) for detecting a selected material species in a fluid stream from conventional gas chromatograph (10, 12) having both gas and liquid phases. Planar electrodes (80, 82) are spaced by an insulator (84) and define borehole diameters (88, 90, 92) which enhance the generated signal-to-noise ratio by providing a short fluid transit time within the conductivity detecting volume compared with the effective time of the chromatographic event of interest. A pneumatic damper (108) may be further included to reduce generated system signal noise.

Abstract: A detection unit having a solute detector and a transport system with a quartz fiber conveyor is disclosed that is particularly useful for liquid chromatography. The quartz fiber conveyor is a porous belt that is mounted at the periphery of a rotatable disc so that the total effluent to be detected is applied to the belt as it is rotated within a heated housing enclosing the disc. The volatile solvent of the effluent is removed by evaporation within the heated housing to leave the non-volatile organic solute on the quartz fiber conveyor, which solute is then detected by a solute detector such as a flame ionization detector or a stacked flame photometric detector. After detection, the quartz fiber conveyor is cleaned by hydrogen-oxygen flame and is thus made ready for further transport of effluent. Alternate embodiments of a stacked flame photometric detector and top flame jets connected therewith are disclosed, as is a device to fabricate the quartz fiber conveyor.

Abstract: A method and apparatus for preventing the destruction of an alkali source in a nitrogen-phosphorus detector by certain reactive and derivatizing reagents encountered in gas chromatography is disclosed. Protection is afforded by lowering the temperature of an electrically heated alkali source during the period in which offensive substances in a gas under analysis are eluted, with the temperature of the source being restored after passage of the offensive substances. The temperature of the alkali source is changed by altering the current through an electrical resistance heater with a temperature control circuit that utilizes a wheatstone bridge.

Abstract: An electrolytic conductivity detector system is disclosed that is particularly useful for gas chromatography. Small gas molecules that will support conductivity are conducted to a gas-liquid contactor where the gas is mixed with a solvent to form a heterogeneous gas-liquid mixture. The gas-liquid mixture is thereafter directed to a gas-liquid separator and a conductivity cell where liquid phase is separated from gas phase and separated liquid phase utilized for conductivity measurement. A unitized gas-liquid separator-conductivity cell may be utilized that includes an inner electrode tube extending upwardly into a larger diameter bore of a metallic outer electrode block, the portion between the block and upper portion of the tube forming a liquid phase reservoir with the liquid phase in the reservoir being utilized for conductivity measurement while between the two electrodes.

Abstract: An electrolytic conductivity detector is disclosed that is particularly useful for gas chromatography. Small gas molecules that will support conductivity are conducted to a gas-liquid contactor where the gas is mixed with a solvent to form a heterogeneous gas-liquid mixture. The gas-liquid mixture is thereafter directed to a unitized gas-liquid separator-conductivity cell where liquid phase is separated from gas phase and separated liquid phase utilized for conductivity measurement. The preferred embodiment of the unitized gas-liquid separator-conductivity cell includes an inner electrode tube extending upwardly into a larger diameter bore of a metallic outer electrode block, the portion between the block and upper portion of the tube forming a liquid phase reservoir with the liquid phase in the reservoir being utilized for conductivity measurement while between the two electrodes.