Electrolytes asymmetrical solutions

Spherical micelles or globular proteins in solution can be considered as an asymmetric electrolyte solution where the ionic species grossly differ in charge and size. Taking into account these asymmetries, an extension of WOZ equa-... 

Kalyuzhnyi, Yu.V., and Vlachy, V. Integral-equation theory for highly asymmetric electrolyte-solutions. Chemical Physics letters, 1993, 215, No. 5, p. 518-522. 

The performance of joint displacement of several macroions with their counterion dresses has not yet been investigated systematically. However, it has been used to examine the location of the gas-liquid binodal curve of asymmetric electrolyte solutions [22]. Figure 21 shows three snapshots from... 

Marmur [12] has presented a guide to the appropriate choice of approximate solution to the Poisson-Boltzmann equation (Eq. V-5) for planar surfaces in an asymmetrical electrolyte. The solution to the Poisson-Boltzmann equation around a spherical charged particle is very important to colloid science. Explicit solutions cannot be obtained but there are extensive tabulations, known as the LOW tables [13]. For small values of o, an approximate equation is [9, 14]... 

The first term on the right-hand side of this equation is zero, since it is simply the sum of the electrical charge in solution, which must be zero for a neutral electrolyte solution. The third term is also zero for electrolytes with equal numbers of positive and negative ions, such as NaCl and MgSC>4. It would not be zero for asymmetric electrolytes such as CaCE. However, in the Debye-Huckel approach, all terms except the second are ignored for all ionic solutions. Substitution of the resulting expression into equation (7.20) gives the linear second-order differential equation... 

The formation of new nuclei and of a fine-crystalline deposit will also be promoted when a high concentration of the metal ions undergoing discharge is maintained in the solution layer next to the electrode. Therefore, concentration polarization will have effects opposite those of activation polarization. Rather highly concentrated electrolyte solutions, vigorous stirring, and other means are employed to reduce concentration polarization. Sometimes, special electrolysis modes are employed for the same purposes currents that are intermittent, reversed (i.e., with periodic inverted, anodic pulses), or asymmetric (an ac component superimposed on the dc). 

For asymmetrical electrolytes the ionic strength is the same for, say, 1 2 as for 2 1 solutes namely, 3 M as verified by substitution into the summation (and remembering the stoichiometry of the dissociation ). Therefore in a 0.01 M solution of 2 1 electrolyte... 

Enantiomeric separations of amino acids and short peptides are performed using either a direct or the indirect approach [10]. The indirect approach employs chiral reagents for diasteromer formation and their subsequent separation by various modes of CE. The direct approach uses a variety of chiral selectors that are incorporated into the electrolyte solution. Chiral selectors are optically pure compounds bearing at least one functional group with a chiral center (usually represented by an asymmetric carbon atom) which allows sterically selective interactions with the two enantiomers. Among others, cyclodextrins (CDs) are the... 

In this study we restrict our consideration by a class of ionic liquids that can be properly described based on the classical multicomponent models of charged and neutral particles. The simplest nontrivial example is a binary mixture of positive and negative particles disposed in a medium with dielectric constant e that is widely used for the description of molten salts [4-6], More complicated cases can be related to ionic solutions being neutral multicomponent systems formed by a solute of positive and negative ions immersed in a neutral solvent. This kind of systems widely varies in complexity [7], ranging from electrolyte solutions where cations and anions have a comparable size and charge, to highly asymmetric macromolecular ionic liquids in which macroions (polymers, micelles, proteins, etc) and microscopic counterions coexist. Thus, the importance of this system in many theoretical and applied fields is out of any doubt. 

In this paper, we have reviewed some recent applications of the HPTMC method. We have attempted to demonstrate its versatility and usefulness with examples for Lennard-Jones fluids, asymmetric electrolytes, homopolymer solutions and blends, block copolymer and random copolymer solutions, semiflexible polymer solutions, and mixtures. For these systems, the proposed method can be orders of magnitude more efficient than traditional grand canonical or Gibbs ensemble simulation techniques. More importantly, the new method is remarkably simple and can be incorporated into existing simulation codes with minor modifications. We expect it to find widespread use in the simulation of complex, many-molecule systems. 

The electrochemical asymmetric polymerization of achiral pyrrole and di(2-furyl)-2,5 substituted phenylenes within a cholesteric liquid crystal electrolyte solution has been also reported [20-22]. 

Sect. 6, different aspects on the simulation of bulk solutions of asymmetric electrolytes using periodic boundary conditions are given. First a comparison of different boundary conditions is presented in Sect. 6.1. Then, in Sect. 6.2, the Ewald summation is examined, and issues such as system size convergence, energy summation convergence, and optimization of the CPU time are discussed. Section 6.3 contains an analysis of the selection of trial moves, and in particular the usefulness of a cluster move technique is illustrated. Furthermore, a second-level cluster move technique, facilitating simulation of phase-separating systems, will also be treated briefly. 

The first published simulation of solution properties of substantial size and charge asymmetric electrolytes was made over 20 years ago and was restricted to low charge asymmetry, Zr = 12 [103]. Despite much improved computer resources, later simulation studies were still bounded by an upper charge asymmetry Unfit of Zr 20 [21,58,74,104-108). It was first with the... 

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