Surface chemical properties nitrogen

The surface chemical properties of the carbon materials were characterized as follows measurement of pH of carbon slurries (in 0.1 M NaCl solution) [89] neutralization with bases of different strength and dilute HCl according to Boehm s method [63,66] determination of total oxygen/nitrogen content by elemental analysis (with an accuracy of 0.2%) [170] mass loss of carbon samples after heat treatment in a vacuum. Additionally, the number of primary adsorption centers (a,)) was determined from water vapor adsorption isotherms according to the Dubinin-Serpinsky method [171], as was the heat of immersion in water for selected samples [111,172]. The results of these operations are pre.sented in Table 3. For all samples transmission Fourier Transform Infrared (FTIR) spectra and X-ray photoelectron spectra (XPS) were recorded. 

More recently, Szymanski et al. [130] reexamined the influence of nitrogen surface functionalities on the SCR of NO using samples with different chemical properties, but of the same origin and with similar texture. Ammonia-treated... 

The basic physico-chemical properties of the fatty amine surfactants drive their utilities as adjuvants. Such molecules consist of a water-insoluble hydrophobic unit, in this case derived from tallow fatty acid. The water-soluble unit of the molecules consist of two chains of polymeric alkoxides, in these cases ethylene oxide and/or another alkylene oxide, such as propylene oxide. A nitrogen atom in the middle of the molecule connects the water-soluble and water-insoluble parts. Due to the electronic properties of nitrogen with respect to the carbon atom connectors which are usual in surfactants, the molecule has an overall cationic character, thus resulting in improved substantivity (adherence) to the leaf surface. 

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