Effects of different surface properties

Limnell T, Riikonen J, Salonen J, Kaukonen AM, Laitinen L, Hirvonen J, Lehto VP (2006) The effect of different surface treatment and pore size on the dissolution of ibuprofen from mesoporous silicon particles. Eur J Pharm Sci 28 S34-S34 Limnell T, Riikonen J, Salonen J, Kaukonen AM, Laitinen L, Hirvonen J, Lehto VP (2007) Surface chemistry and pore size affect carrier properties of mesoporous silicon microparticles. Int J Pharm 343 141-147... 

Good correlation could be obtained between fiber content and flow time, as well as flow distance in these experiments using mats of four basically different types of fibers and also with mats bonded with three different methods. This shows that the fiber type or method of bonding is less important for the penetration of the polyurethane-based elastomeric matrix polymer than fiber volume fraction and the weight of the reinforcement. The effects of fiber surface properties has not yet been investigated with respect to the effect on the elastomeric matrix polymer flow. 

Particle surface modification could be characterized with the surface energy measurement, ilow the surface energy of dispersed particle affects the ER efiect was systematically addressed by Hao [95]. A set of oxidized polyacrylonitrile (OP) materials of different surface properties were employed for such a purpose. The five kinds of water-free ER fluids composed of oxidized polyacrylonitriles (OP) particle dispersed in a low viscosity silicone oil were used for correlating the ER effect with the particle surface energy. The powdered OP materials with average particle size 0.1-10 pm were treated at 150 C for 8 h, and then dispersed in silicone oil immediately at the particle volume fraction of 35 vol /o. The surface energy was measured by means of the dynamic wicking method [96]. Water and... 

The experimental data bearing on the question of the effect of different metals and different crystal orientations on the properties of the metal-electrolyte interface have been discussed by Hamelin et al.27 The results of capacitance measurements for seven sp metals (Ag, Au, Cu, Zn, Pb, Sn, and Bi) in aqueous electrolytes are reviewed. The potential of zero charge is derived from the maximum of the capacitance. Subtracting the diffuse-layer capacitance, one derives the inner-layer capacitance, which, when plotted against surface charge, shows a maximum close to qM = 0. This maximum, which is almost independent of crystal orientation, is explained in terms of the reorientation of water molecules adjacent to the metal surface. Interaction of different faces of metal with water, ions, and organic molecules inside the outer Helmholtz plane are discussed, as well as adsorption. 

The conversion of parathion is affected by soil constituents in the order kaolinite > smectite > organic matter and is related inversely to the adsorption affinity of these materials for this contaminant (Mingelgrin and Saltzman 1977). Although the extent of hydrolysis differs among soils, it is apparent that soil-surface degradation of parathion is caused by hydrolysis of the phosphate ester bond. The presence of water in the soil-parathion system led to a decrease in the surface-induced degradation of the organic molecule and diminished the effect of natural soil properties on its persistence. 

It should be noted that dielectric and optical properties of the near-the-surface layer of a semiconductor, which vary in a certain manner under the action of electric field, depend also on the physicochemical conditions of the experiment and on the prehistory of the semiconductor sample. For example, Gavrilenko et al (1976) and Bondarenko et al. (1975) observed a strong effect of such surface treatment as ion bombardment and mechanical polishing on electroreflection spectra. The damaged layer, which arises in the electrode due to such treatments, has quite different electrooptic characteristics in comparison with the same semiconductor of a perfect crystalline structure (see also Tyagai and Snitko, 1980). 

Very similar results were obtained from the CV studies of ( )-38 and ( )-39, but the observed anodic shifts of the first redox couples upon complexation with K+ were smaller (50 mV for ( )-38 and 40 mV for ( )-39). The reduction of the anodic shift from 90 mV (in ( )-37) to 40 mV (in ( )-38) can be explained by an increasing average distance between the cation bound to the crown ether and the fullerene surface, as the addition pattern changes from trans-1, to trans-2, and to trans-3 [55], Additionally, the effects of different alkali- and alkaline-earth-metal ion salts on the redox properties of ( )-37 were investigated. As expected, all electrochemical data clearly demonstrate a much larger interaction between crown-ether-bound cations with the negatively charged than with the neutral fullerene core [55],... 

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