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Today, most GC columns are fused silica capillaries with an inner diameter of 100–320 micrometres (0.0039–0.0126 in) and a length of 5–60 metres (16–197 ft). The GC column is located inside an oven where the temperature of the gas can be controlled and the effluent coming off the column is monitored by a suitable detector. [1]
A relatively recent analytical tool that has been used for the separation of UCMs is comprehensive two-dimensional GC ().This powerful technique, introduced by Liu and Phillips [27] combines two GC columns with different separation mechanisms: typically a primary column that separates compounds based on volatility coupled to a second short column that separates by polarity.
A post-column oxidation-reduction reactor is a chemical reactor that performs derivatization to improve the quantitative measurement of organic analytes.It is used in gas chromatography (GC), after the column and before a flame ionization detector (FID), to make the response factor of the detector uniform for all carbon-based species.
Pyrolysis–gas chromatography–mass spectrometry is a method of chemical analysis in which the sample is heated to decomposition to produce smaller molecules that are separated by gas chromatography and detected using mass spectrometry. Pyrolysis is the thermal decomposition of materials in an inert atmosphere or a vacuum.
To prevent the stationary phase from leaking out of the column interior a polymer, stainless steel or ceramic net is usually applied. Depending on the application material- and size-requirements may change. Gas chromatography (GC): Older columns were made of glass or metal packed with particles of a solid stationary phase. More recently ...
Comprehensive two-dimensional gas chromatography, or GC×GC, is a multidimensional gas chromatography technique that was originally described in 1984 by J. Calvin Giddings [1] and first successfully implemented in 1991 by John Phillips and his student Zaiyou Liu. [2] GC×GC utilizes two different columns with two different stationary phases. In ...
Gas chromatography-mass spectrometry (GC-MS) is a two-dimensional chromatography technique that combines the separation technique of gas chromatography with the identification technique of mass spectrometry. GC-MS is the single most important analytical tool for the analysis of volatile and semi-volatile organic compounds in complex mixtures. [7]
Most commonly, the FID is attached to a gas chromatography system. The eluent exits the gas chromatography column (A) and enters the FID detector’s oven (B). The oven is needed to make sure that as soon as the eluent exits the column, it does not come out of the gaseous phase and deposit on the interface between the column and FID.