GC, operating conditions

The GC operating conditions are as follows split/splitless injector and detector are held fixed at 260°C and 290°C, respectively. After injection, the oven temperature is kept at 100°C for 2 min, and then programmed at a rate of 35°C/min to a final temperature of 278°C. Helium is used as a carrier gas. 

The following GC operating conditions are optimal for phenolic compounds, including those present in spent pulping liquor or bleaching effluent with or without prior O-acetylation and subsequent O-methylation or O-ethylation ... 

Together with determination of the optimum GC operating conditions, selection of an apropriate MS mode is of primary importance in conducting a successful GC-MS analysis. 

Mass spectral quality is an important consideration in performing a successful GC-MS analysis. The quality of the mass spectra depends on (1) the concentration of the constituents in the sample solution, (2) the GC operating conditions used to resolve the peaks, and (3) excessive pressure fluctuation in the MS unit of the GC-MS system leading to distortion of the mass spectrum, especially an El mass spectrum, as reflected in the relative abundance of the ion peaks. The implication of (3) is that distortions of this type could lead to misinterpretation of the spectrum even though a library search is performed. 

Table 2.3 GC operating conditions and parameters suitable for the analysis of amphetamine derivatized with carbon disulfide...

Table 5.3 Typical GC operating conditions and parameters snitable for the analysis of opiate drags by nsing GC-FID or GC-MS...

Table 7.3 GC operating conditions and parameters used for the GC-MS analysis of mescaline [11]...

Before samples are prepared and analytes quantitatively determined by instrumental analysis, the laboratory must demonstrate that the instrumentation is in sound working order and that targeted analytes can be separated and quantitated. For example, GC operating conditions must be established... 

Table 4.12 GC Operation Conditions Used to Conduct Duai Mega-Bore Capiiiary GC-NP Detection...

Gas Chromatography-Mass Spectromehy (GC-MS) Analysis. The concentrated isolate was analyzed by GC-MS using a Hewlett-Packard 5840A gas chromatograph coupled to a Hewlett-Packard 5985B mass spectrometer equipped with a direct split interface and the same column used for the gas chromatography. The GC operating conditions were the same as described above. Mass spectra were obtained by electron ionization at 70 eV and an ion source temperature of 250°C. 

Perform a blank run (see Section 29.1.1) by following the same GC-operating conditions described in Table 29.1. 

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