Surface charge distribution

The polyelectrolyte chain is often assumed to be a rigid cylinder (at least locally) with a uniform surface charge distribution [33-36], On the basis of this assumption the non-linearized Poisson-Boltzmann (PB) equation can be used to calculate how the electrostatic potential

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In conclusion to this part it seems noteworthy that in contrast to the effect of adsorption of molecular particles on electrophysical properties of oxide semiconductors, the major peculiarity of this effect for such chemically active particles as the simplest free radicals or atoms of simple gases (H2, O2, N2, CI2, etc.) is that they are considerably more chemically active concerning the impurity centres [47]. The latter are responsible for dope conductivity of oxide semiconductors. As for the influence of electric fields on their adsorption due to adsorption-induced surface charge distribution, they are of minor importance which is proved by results of the experiments on assessing field effect on adsorp-... 

A polyelectrolyte solution contains the salt of a polyion, a polymer comprised of repeating ionized units. In dilute solutions, a substantial fraction of sodium ions are bound to polyacrylate at concentrations where sodium acetate exhibits only dissoci-atedions. Thus counterion binding plays a central role in polyelectrolyte solutions [1], Close approach of counterions to polyions results in mutual perturbation of the hydration layers and the description of the electrical potential around polyions is different to both the Debye-Huckel treatment for soluble ions and the Gouy-Chapman model for a surface charge distribution, with Manning condensation of ions around the polyelectrolyte. 

For a solid surface with two-dimensional periodicity, such as a defect-free crystalline surface, all the measurable quantities have the same two-dimensional periodicity, for example, the surface charge distribution, the force between a crystalline surface and an inert-gas atom (Steele, 1974 Goodman and Wachman, 1976 Sakai, Cardino, and Hamann, 1986), tunneling current distribution, and STM topographic images (Chen, 1991). These quantities can be expanded into two-dimensional Fourier series. Usually, only the few lowest Fourier components are enough for describing the physical phenomenon, which requires a set of Fourier coefficients. If the surface exhibits an additional symmetry, then the number of independent Fourier coefficients can be further reduced. 

Biological Materials. The degree of purity ol biological materials severely limits their usefulness. Electrophoresis is a commonly used mclhod of separation and purilicalion of substances such as cells, enzymes and proteins. This lechniquc relies upon the luei that surface charge distribution, and thus mobility in an electric field, vary from one material lo another The degree of separation, product yield, and purity are limited by convection which is caused by coucenlialion gradients within lire process medium. 

To the best of our knowledge, this is the only free energy functional that can be readily introduced in an ASC implicit solvent model as it involves only surface integrals in terms of the independent polarization variable which is no longer a three-dimensional field, but instead assumes the form of a surface charge distribution on the dielectric boundary. 

The surface properties of colloids depend on the organization and structuring of their aqueous environment, which is best modeled, at the present time, using explicit water clusters. The orientation of bound water molecules depends on a number of factors including the surface charge distribution, polarization and... 

We have also to say a few words about a smeared out analogue utilized in our consideration to represent the surface charge distribution. There was an indication in the literature that the image interaction within this adsorption layer may influence the interaction on a macroscopic scale, i.e., which is being commensurate with the range of colloidal forces [29]. However, later results... 

The surface charge distribution of the protein. This is determined by... 

The solute-solvent potential term VJ represents the electrostatic interaction between the solute nuclei and electrons and the apparent surface charge distribution polarized medium. In the computational practice a boundary-element method (BEM) is applied by partitioning the cavity surface into discrete elements, called tesserae, and by substituting the apparent charge a by a collection of point charges qk, each one placed at the center of a tessera sk. The point charges can be obtained as ... 

THE POISSON-BOLTZMANN EQUATION FOR A SURFACE WITH AN ARBITRARY FIXED SURFACE CHARGE DISTRIBUTION... 

A halobacterial ferredoxin has a domain rich in aspartate and glutamate that extends from the main body of the molecule (Sussman et al., 1989). The surface charge distribution may increase hydration and may be necessary for function in a saline environment. 

M. Durbha and M. E. Orazem, "Current Distribution on a Rotating Disk Electrode Below the Mass-Transfer Limited Current Correction for Finite Schmidt Number and Determination of Surface Charge Distribution," Journal of The Electrochemical Society, 145 (1998) 1940-1949. 

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