Electric charge, discrete nature

Equation (19) relates the dependence of the pzc on the concentration of the electrolyte solution in the presence of specific adsorption (F 0 when au = 0) and its variation with the electrode charge. The dependence of the pzc of a mercury electrode on the logarithm of KI concentration was used for the first time for studying the iodide specific adsorption in [17] and later was named the Esin-Markov effect. As follows from the model theories of the electric double layer (see Sect. 3.2), the limiting slope of the aforementioned dependence should tend to the value —RT/kF, where the coefficient X(0 < X < 1) characterizes the discrete nature of the charge of specifically adsorbed anions. 

Surfaces Having Discrete Electrical Charges. The final class of adsorbent surface is the most complex of the three for several reasons. From the standpoint of the nature of the surface, these materials are capable of undergoing adsorption by all of the previously mentioned mechanisms. Possibly more important, however, is the fact that adsorption involving charge-charge interactions is significantly more sensitive to external conditions such as pH, neutral electrolyte, and the presence of nonsurface-active cosolutes than are the other mechanisms. 

Apart from considerations of amplifier noise, good shielding and protection from other external interferences, there is one basic limitation of resolution to any electrical measurement, which is the discrete nature of charge carriers. The best known example of its consequences is the so-called resistor noise or thermal (Johnson) noise which is given by ... 

The electrical, magnetic, optical, and catalytic properties of transition metal nanoparticles differ decisively from those of the bulk phase. The peculiar effects of nanoparticle size, shape, and electronic structure are of interest both from the perspective of fundamental research and applications in energy research (Roduner, 2006 Yaca-man et al., 2001). Specific phenomena at particle sizes below 2 nm arise from the confinement of (quasi)-free electrons and the increasingly discrete nature of the electronic structure (Halperin, 1986). In electrocatalysis, the primary interests are to understand (i) the classical effects of atom arrangement and (ii) the heterogeneous electronic structure at the nanoparticle surface, controlling interfacial adsorption and charge transfer phenomena. 

Hoburg and Melcher [7] demonstrated electrohydrody-namic instabilities in macroscale systems at an oil-oil interface with a discrete conductivity change at the interface under the influence of an applied electric field. In the presence of an applied electric field, charge accumulates at the fluid-fluid interface and the electrical force on the interface is balanced by the fluid interfacial stress tensor. At a critical field sfrength the electrical force exceeds the interfacial fluid forces and interfacial perturbations grow exponentially. Melcher determined a natural velocity scale for this instability, termed the electroviscous velocity which represents a balance between the electrical and viscous stresses at the fluid-fluid interface defined as... 

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