Electric diffuse

An electroosmotic flux is formed as a result of the effect of the electric field in the direction normal to the pores in the membrane, delectric diffuse layer in the pore with a charge density p. The charges move in the direction of the x axis (i.e. in the direction of the field), together with the whole solution with velocity v. At steady state... 

Depending on the kinetics of the chemical step, the reaction layer can either overlap the diffusion layer or the electric diffuse double layer. The latter will be discussed in Sect. 3.5. 

The discussion up to this point has been concerned essentially with metal alloys in which the atoms are necessarily electrically neutral. In ionic systems, an electric diffusion potential builds up during the spinodal decomposition process. The local gradient of this potential provides an additional driving force, which acts upon the diffusing species and this has to be taken into account in the derivation of the equivalents of Eqns. (12.28) and (12.30). The formal treatment of this situation has not yet been carried out satisfactorily [A.V. Virkar, M. R. Plichta (1983)]. We can expect that the spinodal process is governed by the slower cation, for example, in a ternary AX-BX crystal. The electrical part of the driving force is generally nonlinear so that linearized kinetic equations cannot immediately be applied. 

Determine the thickness of the electrical diffuse double layer for a negatively charged solid particle in the following aqueous electrolyte solutions at 20°C a) 0.1 mol/L NaCl, b) 0.001 mol/L CaCl2, c) 0.0001 mol/L A1C13. 

The process of particle collision is governed by physical factors such as diffusion, temperature, fluid shear, particle and fluid density, and the size of particles and aggregates. Whether particles will adhere when they collide is considered to be a function of conditions at the interface between the two solid particles and the fluid medium. Chemical interactions at the solid-liquid interface are responsible for the development of surface charge and potential, the electric diffuse layer, and hydration and hydrophobic effects which determine the probability of particle attachment. 

Figure 4. The dependence of the ellipticity of bacteriorhodopsin reconstituted in vesicles on the electric diffusion potentials. The ordinate is the decrease of the CD signal at 210 nm induced by 10 7-M valinomycin. The abscissa is the electrical potentials calculated by the Nemst equation. The sign indicates the polarity inside the vesicle.

A charged particle immersed in a liquid containing an electrolyte is surrounded by the electrical diffuse double layer. The thickness of the electrical double layer is given by the Debye length 1/k (k = Debye-Hiickel parameter). For a general electrolyte composed of N ionic mobile... 

Formulating the flux equations in terms of the chemical potential gradient only implies that the fluxes occur in metals or semi-conductors without the build-up of an electrical diffusion potential. 

Calculations involving diffusion processes in inhomogeneous multicomponent ionic systems have been recently performed by Kirkaldy [30] and Cooper [38]. They worked with the same assumptions that have been made in this section in which quasi-binary systems have been discussed constant molar volume of the solid solution, and independent fluxes of ions, which are coupled only by the electrical diffusion potential. The latter can be eliminated by the condition zJi 0 which means that local electroneutrality prevails. With these assumptions, and with a knowledge of the thermodynamics of the multicomponent system (which is a knowledge of the activity of the electroneutral components as a function of composition), the individual ionic fluxes can be calculated explicitly with the help of the ionic mobilities and the activity coefficients of the components. 

Scoping calculations to evaluate different container spacing requirements were performed early during the design stages with General Electric diffusion codes and the KENO Monte. Carlo with Hansen and Roach cross sections. Since the KENO Code predicted much hi d>er reactivity values than the diffusion codes, it was selected as the tool to analyze the final stacker design to assure conservative results. 

Field flow fractionation (FFF) can also be used for microbial cell separation. In the FFF technique, a field (may be gravitational, centrifugal, thermal-gradient, electrical, magnetic, etc.) is applied perpendicular to the fluid flow, causing particles to migrate with different velocities. Fields of sedimentation, diffusion, and electrical diffusion are manipulated to optimize the separations of microbes. Separation of Pseudomonas putida and E. coli has been achieved by hyperlayer FFF. Fractions of the whole cells were collected after the separation at different time intervals, dif-... 

The system considered consists of a charged interface including a compact layer between two immiscible ionic solutions with dielectric constants c and e. The surface charge density is compensated by the integral charges of two electrical diffuse layers of thickness k =(0RT/8 ttz (with the concentration in... 

Answer by Author Density, of course, is one of the constituent properties of thermal diffusivity. The analog of thermal diffusivity is i/RC,the electrical diffusivity. 

Electrical Diffuse electrolyte double layer layer... 

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