Surfactant ionic inorganic species

Surfactants are often used to increase the foliar uptake of minerals by plants. Nelson and Garlich [276] have examined the effects of over seventy surfactants and found several anionic, cationic and non-ionic surfactants which increased Fe uptake without burning the leaf tissue. There is some conflict in the literature individual authors have found that one surfactant will enhance the absorption of one inorganic species but prevent another s absorption. For example, Triton X-100 greatly enhances the absorption of P by apple leaves but reduces uptake... 

These interactions are frequently ionic in character. The coulombic forces of interaction between macroions and lower molecular weight ionic species are central to the life processes of the cell. For example, intermolecular interactions of nucleic acids with proteins and small ions, of proteins with anionic lipids and surfactants and with the ionic substrates of enzyme catalyzed reactions, and of ionic polysaccharides with a variety of inorganic cations are all improtant natural processes. Intramolecular coulombic interactions are also important for determining the shape and stability of biopolymer structures, the biological function of which frequently depends intimately on the conformational features of the molecule. 

A CZE method was used to separate EDTA complexes of selected trivalent and divalent transition-metal ions. By adding a surfactant to the separation buffer, an improvement in peak shape and short migration times was obtained (341 and Fig. 8). The ions characterized by CIA consist of 147 ionic species, including inorganic anions, inorganic cations, and organic anions (329). 

Foam breakers may include inorganic ions such as calcium, which counteract the effects of electrostatic stabilization or reduce the solubility of many ionic surfactants, organic or silicone materials that act by spreading on the interface and displacing the stabilizing surfactant species, or materials that directly interfere with micelle formation. 

Remarkably, preliminary data also suggest that cyclodextrin columns can be advantageously enployed to separate different classes of anionic and cationic surfactants as well as inorganic ions [23]. For example, the data in Table III (entry 3) indicate that the baseline separation of halide ions is achievable on the 3-CD column. Therefore, it appears feasible that CD bonded phases can be used in lieu of the more expensive ion exchange columns currently required for the HPLC separation of such ionic species. The versatility of this particular... 

A thorough theoretical investigation was made of the dynamic surface properties of mixed anionic-cationic surfactant solutions [50]. This study is more general than previous studies [51], which considered both ionic species to diffuse as an electroneutral combination, because it includes cases where the anionic and cationic surfactants can diffuse to the surface at different rates and will affect the diffusion of their inorganic counterions as well. 

Spectroscopic studies were performed on water in supercritical CO2 microemulsions using an ammonium carboxylate PFPE surfactant (24). FTIR spec-toscopy was used to identify a bulk water phase within the microemulsion capable of solubilizing ionic species and supporting inorganic reactions. In addition, the UV-visible spectrum of the solvatochromic probe methyl orange indicated three microenvironments within the microemulsions (a) a polar microenvironment like that found in dry PFPE reverse micelles (b) bulk water microenvironment and (c) an acidic microenvironment due to CO2 dissolved in water. 

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