A method of detecting gas with a photoionization detector (PID) system. The method includes powering on a photoionization detector, turning off an ultraviolet lamp of the photoionization detector by a controller of the PID system and keeping it turned off during the zero calibration procedure, flowing ambient air from a surrounding environment by a fan of the photoionization detector system past a detector electrode of the photoionization detector, processing an output of the detector electrode by the controller to determine a zero level of the photoionization detector, and storing the zero level in a memory of the photoionization detector system. The photoionization detector system in a detecting mode compares an output of the detector electrode to the zero level to determine if a threshold concentration of a gas is present.

A discharge-based photo ionisation detector (PID) for use with gas chromatography systems is provided. The PID includes a discharge zone in which a plasma can be generated, resulting in the emission of energetic photons. The PID further includes an ionisation zone in which the gas sample to be analysed is bombarded by the photons created in the discharge zone, photo ionising the impurities in the gas sample. The generated current is measured in order to measure the concentration of impurities in the gas sample. Plasma localizing of the plasma in the discharge zone and optical monitoring of the emission from the plasma in the discharge zone may be provided. Methods using such a PID with a split input from a chromatography column or with inputs from two different chromatography columns are provided.

A BID includes: a discharger (2) including a dielectric pipe (8) and a pair of electrodes (14, 16) attached on an outer wall of the dielectric pipe, the pair of electrodes (14, 16) being arranged at a distance from each other in a direction along a central axis of the dielectric pipe (8), the discharger (2) being arranged so that plasma generating gas is introduced from a first end of the dielectric pipe (8) and configured to generates dielectric barrier discharge inside the dielectric pipe (8) to generate plasma; a detection section (4) including a sample gas introduction section (31) and a collection electrode (26) for collecting ions, the detection section (4) being configured to ionize components in the sample gas using light emitted from the plasma generated in the discharger (2) and to detect the generated ions by collecting them using the collection electrode (26); and a voltage supply (6; 6) for generating a potential difference between the pair of electrodes (14, 16).

A method to simulate distillation of a petroleum stream by gas chromatography can include separating the petroleum stream with a gas chromatograph as a function of boiling point; passing the separated petroleum stream through a vacuum ultraviolet detector to yield data comprising a vacuum ultraviolet signal as a function of boiling point; integrating the vacuum ultraviolet signal as a function of boiling point over two or more wavelength ranges to derive relative concentrations of two or more components of the separated petroleum stream that correspond to the two or more wavelength ranges.

To suppress baseline current other than baseline current derived from the ionization of impurities, and to achieve the enhancement of the SN ratio of a detection signal and the improvement of the lower limit of detection, the inner diameter of a bias electrode for collecting an ion derived from a sample component is made smaller than the inner diameter of an insulating member separating the bias electrode and a collector electrode. Light emitted from plasma formed by dielectric barrier discharge is shielded by the bias electrode, so that the light is not cast directly on the surface of the insulating member. Therefore, the photoelectric effect caused by casting light of high energy does not occur on the surface of the insulating member, whereby a decrease in electric resistance of the surface can be prevented.

An apparatus detects a target gas in ambient air. The apparatus has a GC column, a sensor downstream of the GC column, a pump, a gas storage chamber and a pneumatic circuit. The pneumatic circuit has two states. In a first state, the pump draws in ambient air and supplies it to the gas storage chamber to store ambient air under pressure within the chamber, while trapping a sample of ambient air within the pneumatic circuit. In the second state, the gas storage chamber is connected to the GC column to cause pressurised air drawn from the storage chamber to act as a carrier gas to advance the trapped sample through the GC column and sensor. A filter is filters out any target gas present in the air entering into, or the air drawn from, the storage chamber, to avoid the presence of any target gas in the carrier gas.

A gas phase component analysis device and a gas phase component analysis method that can prevent degradation of the device due to an unnecessary component and can obtain excellent detection sensitivity are provided. A gas phase component analysis device (1) includes a heating unit (2) configured to heat a specimen to generate a gas phase component composite, a first column (31) into which the gas phase component composite is introduced, a second column (32) that is a separation column connected with the first column (31) through a connection unit (33), an isothermal oven (3) housing the first column (31), the second column (32), and the connection unit (33), a detection unit (4) configured to detect a gas phase component having passed through the second column (32), and a suction unit (5) connected with the connection unit (33).

A method of detecting gas with a photoionization detector (PID) system. The method includes powering on a photoionization detector, turning off an ultraviolet lamp of the photoionization detector by a controller of the PID system and keeping it turned off during the zero calibration procedure, flowing ambient air from a surrounding environment by a fan of the photoionization detector system past a detector electrode of the photoionization detector, processing an output of the detector electrode by the controller to determine a zero level of the photoionization detector, and storing the zero level in a memory of the photoionization detector system. The photoionization detector system in a detecting mode compares an output of the detector electrode to the zero level to determine if a threshold concentration of a gas is present.

The invention relates to a system and micro monitor apparatus, a space-, time-, and cost-efficient device to concentrate, identify, and quantify organic compounds in gas environments. The invention further relates to a method centered on gas chromatography for identifying and quantifying organic compounds in gas environments, using air as the carrier gas, without the need for a compressed pre-bottled purified carrier gas.

An integrated microfluidic photoionization detector (PID) is provided including a microfluidic ionization chamber a microfluidic ultraviolet radiation chamber that is configured to generate ultraviolet photons. An ultrathin transmissive window is disposed between the microfluidic ionization chamber and the microfluidic ultraviolet radiation chamber that permits the ultraviolet photons to pass from the microfluidic ultraviolet radiation chamber into the microfluidic ionization chamber. Detection systems for one or more VOC analytes are also provided that include a gas chromatography (GC) unit including at least one gas chromatography column and an integrated microfluidic photoionization detector (PID) disposed downstream of the gas chromatography (GC) unit.