Environmental applications nitrogen compounds

The solvent extracts can be cleaned up by traditional column chromatography or by solid-phase extraction cartridges. This is a common cleanup method that is widely used in biological, clinical, and environmental sample preparation. More details are presented in Chapter 2. Some examples include the cleanup of pesticide residues and chlorinated hydrocarbons, the separation of nitrogen compounds from hydrocarbons, the separation of aromatic compounds from an aliphatic-aromatic mixture, and similar applications for use with fats, oils, and waxes. This approach provides efficient cleanup of steroids, esters, ketones, glycerides, alkaloids, and carbohydrates as well. Cations, anions, metals, and inorganic compounds are also candidates for this method [7],... 

See alsa Atomic Absorption Spectrometry Electrothermal. Atomic Emission Spectrometry Flame Photometry. Cadmium. Carbon. Chemiiuminescence Overview. Fluorescence Environmental Applications. Gas Chromatography Environmental Applications. Laser-Based Techniques. Lead. Nitrogen. Ozone. Polycyclic Aromatic Hydrocarbons Environmental Applications. Remote Gas Sensing Overview. Spectrophotometry Inorganic Compounds. Sulfur. X-Ray Fluorescence and Emission X-Ray Fluorescence Theory. 

Nitrogen compounds are a small but rapidly growing group of flame retardants which are in the focus of public interest concerning environmentally friendly flame retardants. Today, their main applications are melamine for polyurethane flexible foams, melamine cyanurate in nylons, melamine phosphates in polyolefins, melamine and melamine phosphates or dicyandiamide in intumescent paints, guanidine phosphates for textiles and guanidine sulfamate for wallpapers. 

The PID is mainly used for the analysis of aromatic pollutants, for example, BTEX or PAH, or halogenated compounds in environmental applications. Many EPA methods, for example, 602, 502 or 503.1, cover priority pollutants in surface or drinking water. Typical for the PID is the detection of impurities air, also with mobile detectors. This is due to the fact that the energy of the UV lamp is sufficient to ionize the majority of organic air contaminants, but insufficient to ionize the air components oxygen, nitrogen, water, argon and carbon dioxide. 

The NO + 03 chemiluminescent reaction [Reactions (1-3)] is utilized in two commercially available GC detectors, the TEA detector, manufactured by Thermal Electric Corporation (Saddle Brook, NJ), and two nitrogen-selective detectors, manufactured by Thermal Electric Corporation and Antek Instruments, respectively. The TEA detector provides a highly sensitive and selective means of analyzing samples for A-nitrosamines, many of which are known carcinogens. These compounds can be found in such diverse matrices as foods, cosmetics, tobacco products, and environmental samples of soil and water. The TEA detector can also be used to quantify nitroaromatics. This class of compounds includes many explosives and various reactive intermediates used in the chemical industry [121]. Several nitroaromatics are known carcinogens, and are found as environmental contaminants. They have been repeatedly identified in organic aerosol particles, formed from the reaction of polycyclic aromatic hydrocarbons with atmospheric nitric acid at the particle surface [122-124], The TEA detector is extremely selective, which aids analyses in complex matrices, but also severely limits the number of potential applications for the detector [125-127],... 

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