Microelectrophoresis, aqueous

The multilamellar dispersions or vesicles were formed in the conventional manner (4). Drying down the lipid and suspending it in the desired aqueous solution (0.1M NaCl, 0.01M tris, pH 7.5) yielded, on gentle agitation, vesicles of the appropriate size for microelectrophoresis... 

Fedkin, M.V. et al.. High temperature microelectrophoresis studies of the rutile/ aqueous solution interface, Langmuir, 19, 3797, 2003. 

Yang, Ch. et al.. Measurement of the zeta potential of gas bubbles in aqueous solutions by microelectrophoresis method, J. Colloid Interf. Sci., 243, 128, 2001. 

The dense silica (DS) process involves the exposure of titania particles to aqueous silica solutions of increasing silica concentration. The process is examined in this chapter by relating silica adsorption on titania surfaces to solution pH and concentration and to the various monomeric, multimeric, and polymeric species present in aqueous solutions of silica. Microelectrophoresis and gas adsorption studies reveal that adsorption of monomeric silica occurs via hydrated cation sites that constitute only approximately 40% of titania surfaces. These anchoring sites provide a base for complete surface coverage and buildup of silica multilayers (coatings), a buildup that occurs when the silica concentration is increased sufficiently at the chosen pH (around 10 in the DS process) to induce polymerization. 

The industrially produced carotenoids are virtually insoluble in aqueous media. It was therefore a great challenge to develop water-dispersible preparations for the food and feed sector. As has been shown by application tests and animal experiments, sufficient colouring intensity and maximum bioavailability can be achieved by reducing the particle size to less than 0,5 xm. Fig. 2 shows the effect of particle size on the UVA is absorption spectrum of (3,P-carotene (3) in water [95]. The structure and size of particles in the submicrometre range are studied by electron microscopy, dynamic light scattering, microelectrophoresis and UVA is spectroscopy. 

In the conditioning process, under suitable alkaline conditions, both ionization of functional groups at the bitumen surface [33, 105] and adsorption of the natural anionic surfactant molecules at the bitumen/ aqueous interface [100,101,104] occur. Descriptions of the experimental techniques, including microelectrophoresis, employed to study the effects are given elsewhere [100,102,104,106]. Figure 14 shows how addition of NaOH in the process increases the concentrations of surfactant in the aqueous phase, which in turn increases the extents of surfactant adsorption at all of the aqueous phase interfaces present in the system gas/ aqueous, bitumen/aqueous, and solid/aqueous. The adsorption increases until monolayer coverage is achieved and thereafter either levels off or continues into multilayer adsorption. 

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