Ion-exchange complex

Chemical reaction Adsorption of azo dyes at an active site on the surface of material via ion-exchange, complexation, and/or chelation... 

Metal ion binding during biosorption processes has been found to involve a complex mechanism, such as ion-exchange, complexation, electrostatic attraction or micro precipitation. 

There are some cases where a reaction, that is, the formation or dissolution of a chemical bond, is involved along with ion exchange phenomena (Helfferich, 1983). Examples of this are acid-base neutralization, dissociation of weak electrolytes in solution or weak ionogenic groups in ion exchangers, complex formation, or combinations of these (Table 5.2). With some of these, very low apparent D in ion exchangers have been noted. 

Chemisorption is of the following four types ion exchange, complexation, coordination, and chelation. It is the adsorption in which the forces involved are valence forces of the same kind as those operating in the formation of chemical compounds. Some features that are useful in recognizing chemisorption include... 

Reactions such as dissolution, hydrolysis, precipitation, photolysis, adsorption/desorption, oxidation-reduction, ion exchange, complexation, biodegradation, polymerization, and others taking place in the environment, may affect the solubility of pollutants and therefore their mobility, specia-tion, and toxicity. This, in turn, can define to a great extent the dispersion, bioavailability, and risk associated with them. 

V.D.Kopylova, A.N.Astanina, Ion-Exchange Complexes in Catalysis, Khimia, Moscow, 1987. 

Based on the identity of the anion associated with the charged polymer, it can catalyze reactions ranging from oxidation of diol compounds to conversion of alkyl halides to aldehydes Alexandratos etal have synthesized many functionalized polymers for a variety of ion exchange, complexation, and reduction reactions, some of which can be simultaneous. Several other researchers have also synthesized phosphorous-functionalized polymers for ion exchange and metal ion chelation ". ... 

For the establishment of the receptor selectivity, different chemical interactions can be used. For example, the output of potentiometric sensors is strongly influenced by the equilibrium of the analyte with the sensitive layer of the chemosensor. Polymeric matrix membrane-based ion-selective electrodes are utilizing the concentration-dependent extraction of the analyte in the organic layer, while the analyte-dependent shift of potential of ion-selective sensors based on electrodes of the second kind can be described by the solubility product of the hardly soluble salt and the resulting Nemst equation of the electrochemical base reaction. Further equilibria can be predicated on ion exchanges, complexation, or adsorption effects. The interplay of analyte and receptor is determined by... 

Adults oral doses of 20 to 40 mg every 4 hours or 30-60 mg every 6 to 8 hours not to exceed 180 mg daily. Long-acting preparation 60 mg twice a day. The extended-release oral Polistirex suspension delivers dextromethorphan from an ion-exchange complex over a period of 9 to 12 hours. One 60-mg dose of Pohstirex suspension dehvers a plasma concentration similar to two 30-mg doses of immediate-release dextromethorphan given every 6 hours. For preemptive surgical pain control doses between 90 and 120 mg have been used in different clinical trials. Doses employed for control of neuropathic pain are considerably higher (200-300 mg) as tolerated. 

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