In this study, analytical solutions for one-dimensional transport of organic solutes in multilayered porous media are developed using the methods of matrix transfer and variable separation, where multiple factors such as advection, diffusion, mechanical dispersion, adsorption, degradation, boundary condition type and change in concentration are systematically incorporated for the first time. Compared with the existing analytical solutions solved by the techniques of integral transformation or Laplace transformation, the approaches adopted in this paper are simpler and have a quicker convergence speed. Also, the proposed analytical solutions are more practical with clear expressions and consideration of multiple factors, which can be applied to various engineering cases such as bottom liner systems at landfills, covering systems of contaminated sediments and vertical barrier systems in contaminated sites. Furthermore, the correctness of the derived analytical solutions is effectively validated by comparison with the experimental results, as well as with the existing analytical solution and a numerical method. Following this, the effects of different factors on the transport process of a single organic solute in a five-layered medium are investigated, and some novel and vital laws are obtained. Overall, this research contributes to appropriate evaluation of the transport behaviours in multilayered porous media.

中文翻译：

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多层多孔介质中有机溶质输运的分析解决方案

在这项研究中，利用基质传递和变量分离的方法，开发了多层多孔介质中有机溶质一维输运的解析解，其中包括平流、扩散、机械分散、吸附、降解、边界条件类型和浓度的变化首次被系统地纳入。与现有采用积分变换或拉普拉斯变换技术求解的解析解相比，本文采用的方法更加简单，收敛速度更快。此外，所提出的解析解更加实用，表达清晰，考虑多种因素，可应用于各种工程案例，例如垃圾填埋场的底衬系统、覆盖受污染沉积物系统和受污染场地的垂直屏障系统。此外，通过与实验结果、现有解析解和数值方法的比较，有效验证了推导解析解的正确性。随后，研究了不同因素对单一有机溶质在五层介质中传输过程的影响，并获得了一些新颖且重要的定律。总的来说，这项研究有助于适当评估多层多孔介质中的输运行为。以及现有的解析解和数值方法。随后，研究了不同因素对单一有机溶质在五层介质中传输过程的影响，并获得了一些新颖且重要的定律。总的来说，这项研究有助于适当评估多层多孔介质中的输运行为。以及现有的解析解和数值方法。随后，研究了不同因素对单一有机溶质在五层介质中传输过程的影响，并获得了一些新颖且重要的定律。总的来说，这项研究有助于适当评估多层多孔介质中的输运行为。