Biological tissues are multicompartmental heterogeneous media composed of cellular and subcellular domains. Randomly walking water molecules may have different diffusion coefficients and densities (concentrations) in different domains, namely within cells and within the outer medium. Results of the proposed effective media scale-averaging iterative scheme are used to explore the effects of a large range of microstructural and compositional parameters on the apparent (effective) diffusion coefficient. A self-consistent modelling framework for predicting the steady-state effective diffusion coefficient is presented; the framework reveals the strong dependence of the apparent diffusion coefficient on the ratio of the microscopic diffusion coefficients of the comprising phases, permeability of the cells, and their volume fractions.

中文翻译：

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随机结构异质生物材料的扩散问题

生物组织是由细胞和亚细胞结构域组成的多室异质介质。随机行走的水分子在不同的域中可能具有不同的扩散系数和密度（浓度），即细胞内和外部介质内。所提出的有效媒体尺度平均迭代方案的结果用于探索大范围的微观结构和成分参数对表观（有效）扩散系数的影响。提出了一种用于预测稳态有效扩散系数的自洽建模框架；该框架揭示了表观扩散系数对包含相的微观扩散系数、细胞渗透性及其体积分数的比率的强烈依赖性。