Partition coefficient contaminant distribution from

For air-water systems, this equation is known as Henry s law. For solids-water systems, the equilibrium constant is known as the partition coefficient (Ky) or distribution constant (KA). Partition coefficients are available for many organic chemicals from laboratory and field measurements. As organic carbon (OC) present in water (dissolved organic carbon, or DOC), sediment, or soil is the main sink for hydrophobic organic contaminants, the partition coefficients for these compounds are often adjusted (normalized) with respect to the organic carbon content of these compartments ... 

A leaching model based on a sorption-desorption process is used for describing the contaminant release from the waste disposal. The leachate concentration, CL (Bq.m3), is determined by the a distribution or a partition coefficient, Kd (cnr .g1) which describes the relative transport speed of the contaminant to the water existing in the pores soil properties such as bulk density, p (g.cm3), and water content, 0, affect the extent of contamination, described by the contaminated zone thickness, xt (m), area, A (m2) and the amount of contaminant in the source, It (Bq), (EPA 1996 Hung 2000) ... 

The uptake of organic contaminants by plants from biosolids-amended soil depends on the physicochemical properties of organic compoimds and the physiology of plants [92-95]. Plant uptake of organic chemicals and their distribution within plants have been shown to be affected by (1) the organic chemicals physicochemical properties, including solubility, vapor pressure, octanol-water partition coefficient Kow)> and Henry s law constants (iC ), (2) environmental conditions such as temperature, air disturbance and soil organic matter content, and (3) plant characteristics, for example the shape of the leaves, type of root system, and lipid and cuticle characteristics and contents [94]. 

The contamination of food by substances in packaging involves diffusion into the packaging material, controlled by a diffusion coefficient D (units SI m -s ), and the distribution of substances between the packaging and food, controlled by a partition coefficient Kp/p, as well as the sampling of substances from the food side as shown in Figure 13.5. The first two properties are explained in detail in sections 13.4.1 and section 13.4.2, respectively. 

Sorbent extraction Sorbent extraction makes use of the differential distribution of the dissolved compounds between the solid sorbent and water. The use of organic porous polymers is advantageous for the extraction of organic compounds from water because (1) the partition coefficients of compounds in a polymer-water system reach infinity if the correct polymer is selected for the types of contaminants present (2) adsorption of water itself on the polymer is minimal (3) the wettability of the polymer with water makes possible satisfactory transport of the substance toward the polymer surface and (4) the polymer is inert. 

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