Flame-ionization detector, identification

The electron capture detector (ECD) is most frequently used to identify hexachloroethane. A flame ionization detector (FID) may also be used (NIOSH 1994). When unequivocal identification is required, an MS coupled to the GC column may be employed. 

Fig. 4 Gas chromatographic traces of extracts from females of the pale brown chafer Phyl-lopertha diversa monitored by a conventional detector, flame-ionization detector (FID), and a biosensor, electroantennographic detector (EAD), using a male antenna as the sensing element. Although the peak of the sex pheromone (arrow) is hardly seen in the FID trace, its pheromonal activity was initially indicated by the strong EAD peak. Structural elucidation, followed by synthesis and behavioral studies lead to the identification of an unusual sex pheromone, l,3-dimethyl-2,4-(lff,3ff)-quinazolinedione [124]. It is unlikely that this minor compound would be fished out by a bioassay-oriented isolation procedure...

Neon may be analyzed by GC using a thermal conductivity or a flame ionization detector. The gas may be measured by GC/MS using a capillary column. Characteristic masses for its GC/MS identification are 20 and 22. 

The flame ionization detector (FID) can be used for the detection and quantitative estimation of components separated by the GC. Identification of major species can be achieved by a mass spectrometer which can not be used for quantitative analysis of complex mixtures such as coal liquids. 

Isolation and Identification of Hydroperoxide. A solution produced by oxidizing trans-2-butene was concentrated at reduced pressure without heating from 0.085M to 1.5M. The hydroperoxide was isolated from the concentrate by preparative chromatography under the following conditions a 5-foot 3/8-inch column of aluminum containing 10% diisodecyl phthalate on Fluoropak 80 Autoprep 705 with flame ionization detector carrier, 200 ml. per minute helium split 8 to 1 between trap and detector ... 

The more advanced instrumental methods of analysis, including GC, for the detection and identification of expls are presented (Ref 90) Pyrolysis of expls in tandem with GC/MS was used for the identification of contaminant expls in the environment (Ref 108). Isomer vapor impurities of TNT were characterized by GC-electron capture detector and mass spectrometry (Ref 61). Volatile impurities in TNT and Comp B were analyzed using a GC/MS the GC was equipped with electron capture and flame ionization detectors (Ref 79). The vapors evolved from mines, TNT, acetone, toluene, cyclohexanone and an organosilicon, were analyzed by GC/MS (Ref 78). Red water produced by the sellite purification of crude TNT was analyzed by GC/MS for potentially useful organic compds, 2,4-dinitrotoluene, 3- and 4-sulfonic acids (Ref 124). Various reports were surveyed to determine which methods, including GC/MS, are potential candidates for detection of traces of TNT vapors emitted from land mines factors influencing transportability of TNT vapors thru soil to soil/air interface are dis-... 

Melphalan has been converted to its trimethylsilyl derivative with bis(trimethylsilyl)acetamide and has been analyzed by GC on a 1.8 m x 3 mm column packed with 2.5% (w/w) SE-54 on acid-washed, silanized Chromosorb W (80-100 mesh) at 210° (injector temperature, 250° flame ionization detector temperature, 215°) using nitrogen as the carrier at 30 ml/min. The order of elution from a partly hydrolyzed mixture was melphalan, mono-hydroxy-derivative VI and di-hydroxy-derivative VII (Scheme III). The same elution order was obtained on a SE-30 column it was reversed on a more polar liquid phase (OV-17). Identification of the peaks was done by mass spectrometry [52]. 

The recovered lemon oil samples were analyzed by gas chromatography. A 0.5 mm i.d. x 30 m thin film (0.1 pm) SE-30 glass capillary column (Supelco, Inc., Bellefonte, PA) was used with a flame ionization detector. The temperature was programmed from 348 to 473 K. Peak identification was based on information of Supelco, Inc., A. M. Todd Company, and Staroscik and Wilson (] ). Staroscik ( ) provided us with the response values used in his work and we assumed that our detector would give proportionate responses. Staroscik found in his work that relative standard deviations of the response values were generally less than 3%. 

Detectors used to identify DEHP include the electron capture detector (ECD) (Mes et al. 1974 Vessman and Rietz 1974) and the flame ionization detector (FID) (Albro et al. 1984). When unequivocal identification is required, a mass spectrometer (MS) coupled to the GC column might be employed (Ching et al. 1981 a EPA 1986 f Hillman et al. 1975 Sjoberg and Bondesson 1985). Analytical methods for the determination of DEHP in various biological fluids and tissues are summarized inTable7-l. 

The flavor impression of a food is influenced by compounds that affect both taste and odor. The analysis and identification of many volatile flavor compounds in a large variety of food products have been assisted by the development of powerful analytical techniques. Gas-liquid chromatography was widely used in the early 1950s when commercial instruments became available. Introduction of the flame ionization detector increased sensitivity by a factor of 100 and, together with mass spectrometers, gave a method for rapid identification of many components in complex mixtures. These methods have been described by Teranishi et al. (1971). As a result, a great deal of information on volatile flavor components has been obtained in recent years for a variety of food products. The combination of gas chromatography and mass spectrometry can provide identification and quantitation of flavor compounds. However, when the flavor consists of many compounds, sometimes several hun-... 

The identification of individual classes of fatty acids has relied on the use of gas chromatography (GC), equipped with a flame ionization detector. Lipids are sapoiufled after extraction and the fatty acids converted to methyl esters. The fatty acid methyl esters (FAME) are separated using GC. The use of standards ahowed for the identification of individual species of fatty acids based on retention time. The method is quite sensitive and permits the quantification of fatty acid species. The mode of detection has been enhanced with the use of mass spectrometry (MS), which allows for the detection and quantification of unknowns, thus increasing the utility of these methods. The Lipid Library section on the gas chromatography of lipids http //www.lipidlibrary.co.uk/GCJipid/01 intro/index. htm) provides a comprehensive description of these methods. 

The flame ionization detector (FID) is still widely applied for the detection and quantitation of some of the essential oil components, such as terpenoids. As usual in GC/FID, the primary criterion for the identification of peaks is the comparison of the standard retention times with the retention times of peaks in the sample s chromatogram. However, this procedure is sometimes not useful as the identification is quite difficult and overlapping of peaks makes determination not possible. 

The products were analyzed with a Shimadzu organic acid analyzer (LC-IOAD type) and an Okura SSC-1 steam chromatograph with a flame ionization detector and a Porapak R column. The products were found both in the solution and within the coated film. The samples for these analyses were the distillate that was prepared by evaporating 20 cm of the catholyte until 2 cm under reduced pressure. The products adsorbed on the coated film were released into 25 cm of distilled water under ultrasonic irradiation for 5 min. The identification of lactic acid (product) was performed by liquid chromatograph / electrospray mass spectrometry (LC/MS) examining negative ions. The apparatus used was a Hitachi M-1200 LC/MS. 

The emphasis of this work is on the analysis of plastic additives through gas chromatography/mass spectrometry (GC/MS). GC/MS systems are a common analytical tool in quality control and analytical service laboratories and electron impact (El) mass spectra are recognized as reliable data for the identification of organic compounds. Traditional methods have employed a flame ionization detector (FID) with identifications based solely on GC retention time data. These methods lack the specificity necessary to distinguish between components attributable to the sample matrix or the additive(s). 

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