Particles organic coatings

Zhou, J.L., Rowland, S.J., Braven, J., Mantoura, R.F.C. Harland, B.J. (1995b) Tefluthrin sorption to mineral particles role of particle organic coatings. Int. J. Env. Analyt. Chem. 58, 275-85. 

Adsorption of Metal Ions and Ligands. The sohd—solution interface is of greatest importance in regulating the concentration of aquatic solutes and pollutants. Suspended inorganic and organic particles and biomass, sediments, soils, and minerals, eg, in aquifers and infiltration systems, act as adsorbents. The reactions occurring at interfaces can be described with the help of surface-chemical theories (surface complex formation) (25). The adsorption of polar substances, eg, metal cations, M, anions. A, and weak acids, HA, on hydrous oxide, clay, or organically coated surfaces may be described in terms of surface-coordination reactions ... 

Zutib, V., and J. Tomaic (1988), "On the Formation of Organic Coatings on Marine Particles Interactions of Organic Matter at Hydrous Alumina/Seawater Interfaces", Mar. Chem. 23,51-67. 

The particles in natural systems are characterized by a great diversity (minerals, including clays and organic particles organisms - biological debris, humus, macromolecules - and inorganic particles coated with organic matter, etc.) (Table 7.1). 

It is commonly reported that dissolved humic substances (i. e., DHS) tend to coat mineral particles and thereby affect the surface chemistry of those materials. DHS coat the surfaces of solid particles even when they are present at very low concentrations. They furthermore impart a negative charge to the surfaces which they coat. The organic coating is expected to have a great significance on subsequent adsorption of various pollutants [88,91-93,287,288]. 

Similarly, Posfai et al. (1998) carried out AFM and TEM studies of aerosol particles collected over the North Atlantic Ocean. The size of the particles measured under the vacuum conditions of the TEM were smaller than those measured by AFM, due to evaporation of water from the particles. However, the TEM images also showed halos around the particles at the same diameters as the AFM measurements, suggesting that the particles under ambient conditions had an organic coating. This was supported by energy-dispersive X-ray spectrometry (EDS), which showed that these residues contained S, O, and C (although at least some of the C signal may have been due to the substrate). 

Hansson, H.-C., A. Wiedensohler, M. J. Rood, and D. S. Covert, Experimental Determination of the Hygroscopic Properties of Organically Coated Aerosol Particles, J. Aerosol Sci., 21, S241-S244 (1990). 

Fig. 32. Mossbauer spectra of bulk NiFe204 and organic coated NiFe204 particles with and without a magnetic field applied collinear with y-ray direction. Zero velocity is with respect to metallic iron. Reproduced from Berkowilz et al. (223) with permission.

Figure I. Model of a solid particle in an organic medium. The particle is coated with a BG copolymer consisting of A sequences (adsorbed) and B sequences (dissolved).

Loder, T.C. and Liss, P.S., 1985. - Control by organic coatings of the surface charge of estuarine suspended particles. Limnology and Oceanography, 30 418-421. 

In open-column liquid chromatography, the test sample is added to the top of a column packed with adsorbent material (e.g. alumina, silica gel, polymer gel or fine-particle substrate coated with an organic compound). Differential movement... 

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