Aguilella V, Belaya M, Levadny V
Departamento de Ciencias Experimentales, Universidad Jaume I, Castellon, 12080, Spain
J Colloid Interface Sci. 1997 Feb 1;186(1):212-4. doi: 10.1006/jcis.1996.4629.
A perturbation analysis is applied to a nonequilibrium double electric layer (NDEL) near a membrane with extended soft permeable interfaces (polar zones) under steady-state ion flux conditions. The membrane has been modeled as composed of three layers: an inner hydrophobic layer and two polar zones with fixed charges and dipoles. Ion flux is described according to Nernst-Planck and Poisson equations. A first order approximation of the nonequilibrium electric potential has been obtained, using the electric current as the small parameter. The influence of the ionic flux, the surface dipole density, and the thickness of the polar zone on the NDEL near the membrane has been analyzed. The electric potential and hence the ion concentration profiles in the NDEL change considerably with surface dipole density. A maximum in the electric potential, which is determined by ion flux and polar zone parameters, is predicted in certain cases. The effects shown can help in the interpretation of permselectivity measurements.
在稳态离子通量条件下，对具有扩展软渗透界面（极性区）的膜附近的非平衡双电层（NDEL）进行了微扰分析。该膜被建模为由三层组成：一个内部疏水层和两个带有固定电荷和偶极子的极性区。根据能斯特 - 普朗克方程和泊松方程描述离子通量。以电流作为小参数，得到了非平衡电势的一阶近似。分析了离子通量、表面偶极子密度和极性区厚度对膜附近NDEL的影响。NDEL中的电势以及离子浓度分布随表面偶极子密度变化很大。在某些情况下，预测由离子通量和极性区参数决定的电势会出现最大值。所显示的这些效应有助于解释渗透选择性测量结果。
