Effect of Cation

Table 3.1-4 Effects of cation symmetry on the melting points of isomeric tetraalkylammonium salts. In each case the cation (designated [N op] ) has four linear alkyl substituents, together containing a total of 20 carbons. Salts that are liquid at room temperature are indicated by /.

Comparison of Ca3(POi)2, Ca(C204), and Mg3(P04)2. The effects of cation and anion composites were tested by comparing the dissolution of Ca3(P04)2, Ca(C204), andMg3(P04)2 at pH 7 (Table 10). The dissolution of Ca3(P04)2 is achieved more effectively with X than with EDTA. However, when the anion is oxalate, the dissolution of Ca2+ is drastically reduced with X. EDTA can dissolve Ga(C204) to the same extent as Ca3(P04)2, i.e. the anion effect is insignificant. A better separation of Ca2+ from oxalate anion may be achieved by EDTA. 

Affrossman149 observed the accelerating effects of cation-exchange resins partially neutralized with AgOH toward the hydrolyses of allylacetate. 7r-Electron-binding interactions between Ag+ and the double bond in allylacetate were proposed. 7r-Complex formations of olefine with Cu+ and Ag+ have already been reported150 151. ... 

Hetsroni G, Mosyak A, Bemheim-Groswasser A, Talmon Y, Zakin JL (2003c) The effect of cationic surfactant on turbulent flow patterns. J Heat Transfer ASME 125 947-950 Hetsroni G, Mosyak A, Segal Z, Pogrebnyak E (2002a) Two-phase flow patterns in paradel microchannels. Int J Multiphase Flow 9 341-260... 

Chatterjee S., Bohidar H.B. 2005. Effect of cationic size on gelation temperature and properties of gelatin hydrogels. International Journal of Biological Macromolecules 35, 81-88. 

These y9 -peptides are not expected to adopt a 3i4-helical conformation in an aqueous environment because of the destabihzing effect of cationic charges. The circular dichroism spectrum of a non-labeled analog of 165 does not display the characteristic signature of the 3i4-helix in aqueous solution however it is highly hehcoidal in MeOH. 

Table 2.3a. Effect of cation on acidity-basicity Cartledge, 1982a,b)...

Figure 10.57 Effect of cationic softeners on the rewettability of cotton fabric [483] 20 °C, 60% relative humidity...

The Michael addition of alkoxides to nitroalkenes gives generally a complex mixture of products due to the polymerization of nitroalkenes.16 The effect of cations of alkoxides has been examined carefully, and potassium- or sodium-alkoxides give pure p-nitro-ethers in 78-100% isolated yield (Eqs. 4.12 and 4.13).17 When lithium-alkoxides are employed, the yields are decreased to 20-40%. 

Table 5.3 Effect of cation and solvent on hopping rate in durosemiquinone...

Parkinson, B.A., Heller, A., and Miller, B., Effects of cations on the performance of the photoanode in the n-gallium arsenide/potassium selenide (K2Se)-potassium diselenide (K2Se2)-potassium hydroxide/carbon semiconductor liquid junction solar cell, /. Electrochem. Soc., 126,954,1979. 

The following treatment has been suggested by Shiu et al. (1994) and is reproduced briefly below. The simplest, first-order approach is to take into account the effect of dissociation by deducing the ratio of ionic to non-ionic species I, the fraction ionic x and the fraction non-ionic xN for the chemical at both the pH and temperature of experimental data determination (/D, xID, xND) and at the pH and temperature of the desired environmental simulation (/E, xIE, xNE). It is assumed that dissociation takes place only in aqueous solution, not in air, organic carbon, octanol or lipid phases. Some ions and ion pairs are known to exist in the latter two phases, but there are insufficient data to justify a general procedure for estimating the quantities. No correction is made for the effect of cations other than H+. This approach must be regarded as merely a first correction for the dissociation effect. An accurate evaluation should preferably be based on experimental... 

The combined effect of cation interference for both Mg11 and Ca11 is almost identical with the solid curve in Fig. 5.7, indicating that the magnesium ion interference is the dominant one. 

In a study of the pectinesterase from bananas,64,85,102 three pectinesterase fractions were obtained after respective extraction with water, 150 mM sodium chloride, and 150 mM sodium chloride of pH 7.5. The fractions obtained were further purified by fractional salting-out with ammonium sulfate, and chromatography on columns of DEAE- and CM-cellulose. A 50-fold purification was achieved, and the individual, purified fractions were characterized with respect to different effects of cations, inhibition by sucrose, and reaction kinetics. 

The effect of cationic charge on the Lewis acid can be similarly illustrated for the case of NH4+ H-bonded to various first-row hydride Lewis bases,... 

The effect of cations on ene regiochemistry of several intrazeolite photooxygenations have been examined83 (Fig. 20). The effect is modest but the unique... 

Weber WJ, Griffin CW, and Bates JL. Effects of cation substitution on electrical and thermal transport properties of Y0rO3 and LaCr03. J. Am. Ceram. Soc. 1987 70 265-270. 

Ding X, Liu Y, Gao L, and Guo L. Effects of cation substitution on thermal expansion and electrical properties of lanthanum chromites. J. Alloys Compounds 2006 425 318-3 22. 

Figure 7.13 Effect of cationic starch on the relationship between tensile strength and relative bonded area.

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