Electrokinetic equations describing the electrical conductivity of a suspension of colloidal particles are the same as those for the electrophoretic mobility of colloidal particles and thus conductivity measurements can provide us with essentially the same information as that from electrophoretic mobihty measurements. Several theoretical studies have been made on dilute suspensions of hard particles [1-3], mercury drops [4], and spherical polyelectrolytes (charged porous spheres) [5], and on concentrated suspensions of hard spherical particles [6] and mercury drops [7] on the basis of Kuwabara s cell model [8], which was originally applied to electrophoresis problem [9,10]. In this chapter, we develop a theory of conductivity of a concentrated suspension of soft particles [11]. The results cover those for the dilute case in the limit of very low particle volume fractions. We confine ourselves to the case where the overlapping of the electrical double layers of adjacent particles is negligible. [Pg.480]

The fundamental electrokinetic equations for the flow velocity u(r) = (u ug, u ) of the liquid at position r and that of the ith mobile ionic species v,(r) are the same as those for the electrophoresis problem (Chapter 21) except that the Navier-Stokes equations involve the term p g, where p is the mass density and the viscosity of the liquid, namely, [Pg.487]

The fundamental electrokinetic equations for the liquid velocity u(r) at position r relative to the particle (u(r) —> —U as r = Irl oo) and the velocity of the tth ionic species v, are the same as those for rigid spheres except that the Navier-Stokes equations for u(r) become different for the regions outside and inside the surface layer, namely, [Pg.436]

Discuss the physical mechanism that gives rise to the first electrokinetic equation. [Pg.377]

Discuss Eq. (6.8.10) so as to provide insight into the meaning of the first electrokinetic equation. [Pg.567]

For a weak applied filed E, the electrokinetic equations are linearized to give [Pg.437]

O Brien, R. W., The solution of the electrokinetic equations for colloidal particles with thin double [Pg.607]

Mohilner and Delahay [126] derived the electrokinetic equations for specific adsorption of reactant or product [Pg.65]

Making a virtue of necessity, the appropriate electrokinetic equations can be written explicitly in terms of a and then subjected to experimental verification. For instance, [4.3.24] can be transformed to give [Pg.533]

This review is organized as follows. The general electrokinetic equations that govern the flow of an electrolyte are presented in Sec. II along with a description of the infinite spatially periodic porous medium. [Pg.231]

SEDIMENTATION POTENTIAL AND VELOCITY IN A SUSPENSION fundamental electrokinetic equations can be expressed in terms of h and as [Pg.488]

In the presence of fluid flow, exact analytical solutions of the full electrokinetic equations are rare. An exceptional situation arises when the [Pg.788]

Goodenough and co-workers [10] made a detailed study of the solid state chemistry and electrochemistry of ruthenates of general formula Bi(2 2x)P-b2xRu20(7. v) with the pyrochlore structure and reported that the electroreduction of oxygen proceeds at low overpotentials according to the electrokinetic equation [Pg.321]

The first attempt to derive the relation between fi and was made by Von Smoluchowski [10] and Hiickel [11], and later by Henry [12]. Full electrokinetic equations determining electrophoretic mobility fi of spherical particles with arbitrary values of Ka and were derived independently by Overbeek [13] and Booth [14]. Wiersema et al. [15] solved the equations numerically. The computer calculation of the electrophoretic mobility was considerably improved by O Brien and White [16]. Approximate analytic mobility expressions have been proposed by several authors [17-19]. [Pg.28]

In principle, both the potential and charge density at the surface of a porous solid can be calculated from electrokinetic data such as the electro-osmotic transfer rate or the conductivity of a porous plug. Interpretation of this type of experimental data is based on the solution of the so-called electrokinetic equations [10-13] [Pg.588]

To study electrophoresis of particles subject to an external electric field, one needs to know the electrical potential, fluid flow and ion fluxes around the particle. In this section, we first present the fundamental electrokinetic equations for electrophoresis of colloidal particles. Previous studies on the electrophoresis of a single particle will then be reviewed, and important results will be stated. [Pg.585]

If the solution to the problem of the equilibrium double layer is known, then the velocity is determined by the above formula. Thus, the solutions to the respective flow problems for the equilibrium situations considered in the previous subsection are readily written down. Solution to the electrokinetic equations is facilitated if the Debye layer thickness may be assumed small compared to the characteristic channel width Wq. This however is not usually the case in nanochannels since wq and are both on the order of nanometers. Exact analytical solutions [Pg.789]

Relatively complete elaborations for the cylinder model have been given by for instance, Anderson and Koh and Levine et al. K In these two theories the solution Is assumed to contain (1-1) electrolytes with =u. Both theories fail to account for conduction behind the slip plane, and both solve the electrokinetic equations, taking double layer overlap into account. Anderson and Koh assume this overlap to take place at fixed surface charge (which, because of the implicit rigid particle model of the cylinder wall, comes down to fixed tr =cT ), whereas Levine et al. do so for constant surface potential (essentially fixed Anderson and Koh also considered capUlaries of other [Pg.580]

See also in sourсe #XX -- [ Pg.358 ]

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