Effect of hydrophobization

Tian Y, Fendler J FI, Flungerbuhler FI, Guldi D M and Asmus K-D 1999 Effects of hydrophobic-hydrophilic balance and stereochemistry on the supramolecular assembly of functionalized fullerenes Supramol. Sc/. C 7 67-73... 

Calvert correlation parameter for effect of hydrophobic f = 0.25) or hydrophilic f =... 

In most situations the eluent composition is chosen to minimize the effects of hydrophobic interaction, but these secondary effects can be used to advantage. By careful selection of a salt and its concentration, specific selectivities for analytes can be achieved without the use of organic solvents. Therefore, many separations usually run by solvent gradient reversed-phase methods can be completed with a purely aqueous isocratic eluent (13,14). 

Human intestinal absorption of 5 (01JPS749) and 6 (01MI30) was predicted by using five Abraham descriptors and CaCo-2 monolayer, respectively. The effect of hydrophobicity and molecular mass on the accumulation of 10 fluoroquinolones, including 5, by Staphylococcus aureus were evaluated (01MI14). 

For additional evaluation of the effect of hydrophobization and the molecular weight of the polymers on the biological immuno-stimulating activity, we investigated the ex vivo cytokine (interIeukin-6 [IL-6], and tumor necrosis factor [TNFj-inducing activity from human peripheral whole blood cells of hydrophobized polymers by use of fractionated poly(M A-CDA) with narrow poly-dispersity. Since this assay uses the intact human cells, it shows more accurate results than in vitro assay using cultured cell line [25]. 

Effects of Hydrophobic Compartmentalization of Photoinduced Electron Transfer... 

Effect of hydrophobe carbon number on AOS calcium tolerance. The hydrophobe chain branching and the di monosulfonate ratio were held constant in these experiments (5-7% branching and 5-7% disulfonate). Increasing AOS carbon number from 14-16 to 16-18 and finally to 20-24 greatly decreases the calcium ion tolerance of AOS see Fig. 3. Addition of less than 200 ppm calcium ion reduced the transmittance of an AOS 2024 surfactant to less than 10% of its initial value. Addition of more than 300 ppm calcium ion was required to reduce AOS 1618 solution transmittance by a similar amount. AOS 1416 was the most calcium-tolerant surfactant. Approximately 400 ppm calcium ion was required to reduce the transmittance of AOS 1416 solution to 10% of its initial value. 

Effect of hydrophobe chain branching. The effects of hydrophobe structure on olefinsulfonate calcium ion tolerance were studied for AOS, IOS, and vinylidenesulfonate (VOS), and the results are shown in Table 7. 

TABLE 10 Effect of Hydrophobe Carbon Number on Interfacial Tension of Olefinsulfonates ... 

The results in Table 22 for a series of one atmosphere 75 °C foaming experiments indicate the effect of hydrophobe carbon number. The foam stability of C18 AS is greater than that of C16 AS in the absence of an oil phase, in the presence of decane, and in the presence of the decane-toluene mixture. The foam stability of C18 HAS is greater than that of C16 HAS in the absence of an oil phase. In the presence of decane and in the presence of the decane-toluene mixture, the foam stability of the C18 HAS is, if anything, slightly less than that of C16 HAS. This may have been the result of partitioning effects. 

Effect of Hydrophobe Carbon Number, Temperature, and Oil Phase1... 

Fig. 10 Scheme for explaining the effect of hydrophobic interactions on the DS obtained. 

Klotzbach T, WattM, Ansari Y, Minteer SD. 2006. Effects of hydrophobic modification of chit-osan and Nafion on transport properties, ion-exchange capacities, and enzyme immobilization. J Membrane Sci 282 276-283. 

The effect of hydrophobicity of the polymer on the permeability of poly(2-hydroxyethyl methacrylate (HEMA)-co-methacrylic acid (MAAc) hydrogels was studied [12], The hydrophobicity was controlled by copolymerization with butyl methacrylate (BMA). The dependence of permeability on pH increased as the hydrophobicity increased even though the rate of diffusion decreased. Cross-link density of the hydrogel also contributed to pH-dependent permeability. 

Figure 10.1 Lyotropic series effectiveness of hydrophobic interactions [1]...

Lim, G., and Wang, C. Y. Effect of hydrophobic polymer content in GDL on power performance of a PEM fuel cell. Electrochimica Acta 2004 49 4149-4156. 

G. Lim and C. Y. Wang. Effects of hydrophobic polymer content in GDL on power performance of a PEM fuel cell. Electrochimica Acta 49 (2004) 4149-4156. G. G. Park, Y. J. Sohn, T. H. Yang, et al. Effect of PTFE contents in the gas diffusion media on the performance of PEMFC. Journal of Power Sources 131 (2004) 182-187. 

H. Nakajima, T. Konomi, and T. Kitahara. Direct water balance analysis on a polymer electrolyte fuel cell (PEFC) Effects of hydrophobic treatment and microporous layer addition to the gas diffusion layer of a PEFC on its performance during a simulated start-up operation. Journal of Power Sources 171 (2007) 457-463. 

Kanazawa, H., Kashiwase, Y, Yamamoto, K., Matsushima, Y, Kikuchi, A., Sakurai, Y, and Okano, T. Temperature responsive liquid chromatography 2. Effect of hydrophobic groups in A-isopropylacrylamide copolymer-modified silica, Anal. Chem., 1997, 69, 823-830. 

T. Kawakatsu, G. Tragardh, C. Tragardh, M. Nakajima, N. Oda, and T. Yonemoto The Effect of Hydrophobicity of Microchannels and Components in Water and Oil Phases on Droplet Formation in MicroChannel Water-in-Oil Emulsification. Colloid and Surfaces A Physicochem. Eng. Aspects 179, 29 (2001). 

This paper will review the biodegradation of nonionic surfactants. The major focus will be on alcohol ethoxylates and alkylphenol ethoxylates—the two largest volume nonionics. In this paper the effect of hydrophobe structure will be discussed, since hydrophobe structure is considered more critical than that of the hydrophile in biodegradability of the largest volume nonionics. The influence of the hydrophobe on the biodegradation pathway will be examined with an emphasis on the use of radiolabeled nonionics. 

The effect of hydrophobicity of some ionic liquids was explored (119) in a recent example of a condensation synthesis involving a quaternary ammonium amide. The water produced was continuously removed from the reaction mixture, producing a much higher yield than had previously been possible for this reaction in other media. 

Kiso Y., Y. Sigiura, T. Kitao, and K. Nishimura (2001). Effects of hydrophobicity and molecular size on rejection of aromatic pesticides with nanofiltration membranes. Journal of Membrane Science 192 1-10. 

Raney K, Benton W, Miller CA (1987) Optimum detergency conditions with nonionic siufactants II. Effect of hydrophobic additives. J Colloid Interface Sci 119 539-549 Rosen MJ, Wu Y (2001) Superspreading of trisiloxane surfactant mixtures on hydrophobic siufaces 1. Interfacial adsorption of aqueous trisiloxane surfactant -M-alkyl pyrrolidinone mixtures on polyethylene. Langmuir 17 7296-7305 Stevens PJG, Kimberely MO, Mimphy DS, Policello GA (1993) Adhesion of spray droplets to foliage - the role of dynamic surface tension and advantages of organosil-icone surfactants. Pesticide Sci 38 237-245... 

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