Erratum to: A Cell Model of an Ion-Exchange Membrane. Capillary-Osmosis and Reverse-Osmosis Coefficients

Colloid Journal - An Erratum to this paper has been published: https://doi.org/10.1134/S1061933X22350010     

A Cell Model of an Ion-Exchange Membrane. Electrodiffusion Coefficient and Diffusion Permeability

Colloid Journal - Electrodiffusion coefficient and diffusion permeability of an ion-exchange membrane have been calculated as the kinetic coefficients of the Onsager matrix in terms of the...     

Ion Transport in a Three-Layered Ion-Exchange Membrane: A Mathematical Model

An ion transport model is considered. The model is based on the Nernst–Planck equations, the elements of nonequilibrium thermodynamics, the principle of local equilibrium, and the concept of a virtual solution. The model is applied to an ion-exchange membrane with two diffusion layers for the cases of electrotransport of two and three types of ions. To determine transfer coefficients L ^* _j in the Nernst–Planck equations, two approaches are used. In the phenomenological approach, L ^* _j are found from experimental data on the electroconductivity and transport numbers. In the modeling approach, values of L ^* _j are sought for from a model of a microheterogeneous membrane. The obtained boundary-value problem is solved using a numerical method of parallel shooting developed earlier, which perfectly fits specific features of the problem formulation (utilizing the Nernst–Planck equations in all the three layers and the concept of a virtual solution).     

细胞膜离子通道的一个非线性动力学模型

提出一个关于细胞膜离子通道的非线性动力学模型，此模型克服了Liebovitch模型的一些严重缺陷，也更符合通道中离子运动实际．模型导出的Ⅰ-Ⅴ曲线与实验结果符合得很好．     

Mathematical Model of Electrodiffusion Transfer through a Diffusion Layer–Heterogeneous Ion-Exchange Membrane System

The kinetics of the charge and ion transport in a two-layer system which comprises a diffusion layer and an ion-exchange membrane in a salt solution and involves hydrogen and hydroxyl ions formed from water is modeled mathematically, making it possible to apply mathematical modeling to solving kinetic problems in complex electrodialysis systems where a two-layer problem is just a fragment.     

Estimation of Ion-Exchange Equilibrium Constant Using Membrane Conductivity Data

Colloid Journal - The possibility of calculating the ionic composition of a membrane and the ion-exchange equilibrium constant on the basis of the concentration dependences of the specific...     

Kinetic Parameters of Ion-Exchange Membrane in Amino Acid Solutions

Kinetic parameters of amino acid cations in an MK-40 ion-exchange membrane are calculated from the conductivity data. A theoretical quantum-chemical analysis of experimental activation energies for conduction suggests a mechanism of elementary act of transport of amino acid cations in the membrane.     

质子交换膜燃料电池模型研究进展

综述了质子交换膜燃料电池 (PEMFC)数学模型的研究进展 ,分析PEMFC中膜、催化层、扩散层和流场区域的传递现象和水、热管理的重要性 ,讨论了模型的维数、复杂性和求解方法 .提出了带有时间维数的PEMFC模型研究的实际应用意义     

阳离子交换树脂膜吸附-X荧光光谱法测定矿石中的钍

本文介绍了一种用阳离子交换树脂膜吸附X荧光光谱法测定矿石中钍的方法。在0～250微克/100毫升范围,钍的浓度与强度呈线性关系,当钍含量大于100ppm时,其变异系数为3.38%。     

Establishment of the Model CD40 Cell Membrane Chromatography and Its Chromatographic Characteristics

A new model of atherosclerosis cell membrane chromatography has been established by using a CD40 cell membrane stationary phase (CD40 CMSP) prepared by immobilizing the CD40 cell membrane onto the surface of a silica carrier. The surface and chromatographic characteristics of CD40 CMSP were studied. The retention characteristics of anti-CD40 antibody and statins (lovastatin, simvastatin and pravastatin) were also investigated using this model. Affinities of the anti-CD40 antibody and statins toward CD40 cell membrane and receptors were based on the determination of log k′ values (the logarithm of capacity factor of a solute). There was a significant correlation between the affinity in the CD40–CMC and the effect in vitro for the pharmacological effect.     

Heterogeneity of Ion-Exchange Membranes: The Effects of Membrane Heterogeneity on Transport Properties

The heterogeneity of different cation-exchange membranes (Neosepta CMX, Selemion CMV, and HJC heterogeneous membrane) and their effects on transport properties were investigated using chronopotentiometry, membrane conductivity, and current-voltage curves. Modifying the classical Sand equation, a method has been developed to determine the fraction of the conducting region (epsilon) of the ion-exchange membrane. The epsilon values of the CMX, CMV, and HJC membranes were 0.93, 0.95, and 0.75, respectively. Considering the characteristics of each membrane-the CMX and CMV are reinforced homogeneous membranes, while the HJC is a heterogeneous membrane-the epsilon values determined in this study seem to be reasonable. The dependence of membrane conductivities and the limiting current densities on the fraction of conducting region of each membrane have also been studied. Copyright 2001 Academic Press.     

Effects of Multisolute Steric Interactions on Membrane Partition Coefficients

A key parameter in membrane and chromatographic separations is the partition coefficient, the equilibrium ratio of the solute concentration in a porous or fibrous material to that in bulk solution. The theoretical effects of solute size on partition coefficients in straight pores or randomly oriented fiber matrices have been investigated previously for very dilute solutions, where solute-solute interactions are negligible, and also for more concentrated solutions consisting of spherical solutes of uniform size. For concentrated solutions it has been found that steric and other repulsive interactions among solutes increase the partition coefficient above the dilute limit. To extend the results for porous or fibrous media to include concentrated mixtures of solutes with different sizes or shapes, we used an excluded volume approach. In this formulation, which describes steric interactions only, partition coefficients were computed by summing all volumes excluded to a solute molecule by virtue of its finite size, the finite size of other solutes, and the presence of fixed obstacles (pore walls or fibers). For a mixture of two spherical solutes, the addition of any second solute at finite concentration increased the partition coefficient of the first solute. That increase was sensitive to the size of the second solute; for a given volume fraction of the second solute, the smaller its radius, the larger the effect. When the total volume fraction of solutes was fixed, an increase in the amount of a second, smaller solute increased the partition coefficient of the first solute, whereas an increase in the amount of a second, larger solute had the opposite effect. Results were obtained also for oblate or prolate spheroidal solutes and for fibrous media containing fibers of different radii. For constant total fiber volume fraction, an increase in the amount of a second, smaller fiber decreased the partition coefficient of a spherical solute, whereas an increase in the amount of a second, larger fiber had the opposite effect. Overall, the theory suggests that the introduction of heterogeneities, whether as mixtures of solute sizes or mixtures of fiber sizes, may cause partition coefficients to differ markedly from those of uniform systems. Copyright 2000 Academic Press.     

质子交换膜燃料电池用膜材料的性能表征

质子交换膜(PEM)是质子交换膜燃料电池(PEMFC)的关键组件之一,其性能的好坏在很大程度上决定了PEMFC的性能。本文对PEMFC膜材料的性能表征进行了综述,讨论了膜材料的孔隙率、密度、粘度、磺化率、稳定性、选择透过性及导电性等性能的表征。     

Kinetic Characteristics of Reverse-Osmosis Separation of an Aqueous Solution of Aniline in a Flat-Frame Apparatus

Reverse-osmosis separation of an aqueous solution of aniline on a flat-frame reverse-osmosis installation was studied for two types of industrial polymeric membranes in relation to the concentration and pressure of the solution in the intermembrane channel. The behavior of the main kinetic characteristics of separation was analyzed and explained for different physical conditions of the process.     

质子交换膜燃料电池及电池组模型分析

本文对现有质子交换膜燃料电池以及电池组模型进行比较分析,认为数学模型的建立,可以增加对燃料电池及电池组内部的传递现象和反应机理的认识,同时可以预测电池以及电池组的性能,并且对优化电池结构参数具有指导意义.模型分析包括了现阶段质子交换膜燃料电池单电池模型和电池组模型的基本类别,它们是单电池CFD数值模拟模型、单电池以及电池组性能模拟模型、燃料电池组气体分配模型、系统模型和非稳态模型.比较了几种模型的建模方式及不同模型的应用范围和各自的优缺点.     

Novel Detection Method of Endocrine Disrupting Chemicals Utilizing Liposomes as Cell Membrane Model

Abstract

A novel detection method of endocrine disrupting chemicals (EDCs) is proposed. Liposomes encapsulating fluorescence dye was prepared as a cell membrane model and applied to detect EDCs. Leakages of dye from liposomes were observed after their exposure to EDCs. Fluorescence intensity increased significantly when the liposomes were exposed to 5 ppm EDCs. The increases showed a good correlation with EDCs' dipole moment. Therefore, polarizability is suggested as one of the factors of the liposome-EDC interaction. At lower than 5 ppm, the increases depended on EDCs' concentration. The tendency of the results was in accordance with reported estrogenic activity of EDCs.     

Sodium Hypochlorite Production in an Electrolyzing Cell with a Ceramic Membrane

Electrochemical synthesis of sodium hypochlorite in a membrane electrolyzing cell with OCTA and a ZrO₂-based inorganic ceramic membrane is studied. Effects of the current density, concentration of the NaCl solution, and the rate of supply of solutions into electrode chambers are investigated. Under optimum conditions, the current efficiency for sodium hypochlorite is 77%, with a specific consumption of power of 2.4 kW h kg^–1and sodium chloride, 3.1 kg kg^–1. The anode's corrosion resistance in the experimental conditions is determined.     

Unbiased Selectivity Coefficients of Potentiometric Sensors Using Thin Membrane Layers

Solid-contact ion-selective electrodes with thin membranes can more easily achieve complete ion exchange at the sample-membrane interface, giving unbiased selectivity coefficients. The calculated reconditioning rate corresponds well to experimental data. Alternatively, the redox state of the conducting polymer may be electrochemically switched resulting in primary ion expulsion from the membrane and interfering ion uptake from the sample. Both approaches were tested for tetrabutylammonium-selective electrodes. The approach's limitations are identified, which includes primary ions impurities in interfering ion salts and an interaction between primary ion and redox polymer. These limitations are visualized with ionophore-based sodium- and silver-selective electrodes.     

A Reduced SNARE Model for Membrane Fusion

Let's get together : A minimal model system was developed to mimic the SNARE‐protein‐mediated fusion of biological membranes (see picture). Fusion between two populations of liposomes is controlled by a pair of complementary lipidated oligopeptides that form noncovalent coiled‐coil complexes and thereby force the membranes into close proximity to promote fusion. The model system displays the key characteristics of in vivo fusion events.

     

全氟磺酸型阳离子交换膜中氯离子和氢氧离子的扩散系数

在不同温度下,Nafion膜的氢氧离子扩散系数与氯离子的扩散系数之间具有相关性。在33种不同化学处理和物理处理的全氟磺酸型膜中,观察到氢氧离子和氯离子之间存在着D_(OH)~-=-7.82×10~(-10)+3.43D_(Cl)~-的关系。我们认为这种相关性,起因于离子的淌度之间的相关性。