Nitrogen compounds ionization mass spectrometry

This system was studied by Schwartz. Toluene at 10 ppm, nitric oxide at 1 ppm, and nitrogen dioxide at 1.2 ppm were irradiated with ultraviolet lamps in a 17-m batch reactor for 270 min. Collected aerosols were successively extracted with methylene chloride and then methanol. The methylene chloride extract was fractionated into water-soluble and water-insoluble material, and the latter fraction was further divided into acidic, neutral, and basic fractions. The acidic and neutral fractions were analyzed by gas chromatography and chemical-ionization mass spectrometry the compounds identified are shown in Figure 3-7. The two analyzed fractions represented only about 5.5% of the total aerosol mass. It is noteworthy that classical nitration of an aromatic ring appears to... 

It is possible to analyze approximately 40 elements by thermal ionization mass spectrometry and another ten elements by electron impact (including gaseous compounds of elements such as nitrogen, oxygen, carbon, and silicon). When isotope dilution is applicable, it usually is by far the most accurate method for the determination of impurities and traces. The leverage for precision and accuracy comes from the limited number of quantitative steps necessary for the analysis. 

Metastable helium atoms or nitrogen molecules are extracted from the plasma and directed to a sample surface, where Penning ionization makes product ions that can be analyzed by mass spectrometry or IMS. DART sources have been used to ionize a number of classes of compounds as solids or adsorbed directly onto a variety of surfaces. 

The most common detection method used in gas chromatography is FID. The nitrogen-phosphorus detector (NPD) can be used to identify nitrogen-containing compounds (Stashenko et al., 1996). Another possibiUty is the use of oxygen flame ionization detection (O-FID) for the selective determination of oxygenates (Betts, 1994 Schneider et al., 1982). Mass spectrometry is a very useful tool for detecting complex terpene mixtures. 

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