Effect of Solvent Exchange

Solvent Volume shrinkage (%) Density (g cm - 3) Porosity (%) Mean pore diameter (nm)/FWHM (nm) 

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Park HC, Moon YS, Rhee HW, Won J> Kang YS> Kim UY (1999) Effect of solvent exchange on the morphology of asymmetric membranes. In Pinnanau I> Freeman BD (eds) Membrane formation and modification. ACS Symposium Series 744. American Chemical Society, Washington, DC, p 121... 

Rao, A P, Rao, A V, Pajonk, G, Shewale, P M (2(X)7) Effect of solvent exchanging process on the preparation of the hydrophobic silica aerogels by ambient pressure drying method using sodium silicate precursor. J Mater Sci 42(20) 8418-8425. 

Ishii, D., Tatsumi, D., Matsumoto, T. (2003], Effect of solvent exchange on the solid structure and dissolution behaviour of cellulose, Biomocromolecules.A, 1238-1243. 

Azo-bridged ferrocene oligomers also show a marked dependence on the redox potentials and IT-band characteristics of the solvent, as is usual for class II mixed valence complexes 21,22). As for the conjugated ferrocene dimers, 2 and 241 the effects of solvents on the electron-exchange rates were analyzed on the basis of the Marcus-Hush theory, in which the t/max of the IT band depends on (l/Dop — 1 /Ds), where Dop and Ds are the solvent s optical and static dielectric constants, respectively (155-157). However, a detailed analysis of the solvent effect on z/max of the IT band of the azo-bridged ferrocene oligomers, 252,64+, and 642+, indicates that the i/max shift is dependent not only on the parameters in the Marcus-Hush theory but also on the nature of the solvent as donor or acceptor (92). 

Quantum chemical methods are well established, accepted and of high potential for investigation of inorganic reaction mechanisms, especially if they can be applied as a fruitful interplay between theory and experiment. In the case of solvent exchange reactions their major deficiency is the limited possibility of including solvent effects. We demonstrated that with recent DFT-and ab initio methods, reaction mechanisms can be successfully explored. To obtain an idea about solvent effects, implicit solvent models can be used in the calculations, when their limitations are kept in mind. In future, more powerful computers will be available and will allow more sophisticated calculations to be performed. This will enable scientists to treat solvent molecules explicitly by ab initio molecular dynamics (e.g., Car-Parrinello simulations). The application of such methods will in turn complement the quantum chemical toolbox for the exploration of solvent and ligand exchange reactions. 

Although there is no direct connection between the rules discussed in Chap. 4 for the monovalent-divalent ion selectivity of ligands in liquid membranes and the electrochemical selectivity behavior of these membranes (cf. Eqs. (22) and (31)), the effect of solvent on Na+/Ca2+ selectivity (Fig. 22) is remarkably similar to the calculated effect shown in Fig. 18 (actually for K+/Ba2+ preference). The discrimination against Mg2+ and especially HaO+ is considerably better for the electrode discussed here 117) than for liquid ion-exchange membranes responsive to Ca2+ (123). 

Table IV Effect of Solvents on the Rates of Chloride Ion Exchange...

The effect of interconversion between the planar and tetrahedral isomers on the NMR spectrum can be described by extension of the analysis for exchange between two diamagnetic sites (149). It should be noted that the well-known analysis of Swift and Connick (146, 148) is not directly applicable, because the paramagnetic site is not dilute, as it is in the case of solvent exchange on a paramagnetic metal ion. 

Bailey, W. F. Brubaker, J. D. Jordan, K. P. Effect of solvent and temperature on the lithium-iodine exchange of primary alkyl iodides reaction of tBuLi with 1-iodooctane in heptane-ether mixtures./. Organomet. Chem. 

The effect of solvent and inert atmosphere on the 18F-fluoride ion exchange reactions... 

Figure 9. Effect of solvent selectivity on annual costs at constant propane activity coefficient (process with heat exchange...

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