Abstract A model for coupled diffusive processes is framed within the theory of partial differential equations of mixed order. Its numerical implementation is achieved by a technique that does not require additional tools beyond the standard procedures for the solution of the diffusion equation. The interface between the diffusant and the substrate retains its sharpness during the bulk of the diffusive process. The results demonstrate that, as expected in pharmaceutical and diffusion bonding applications, the amount of material made available for diffusion is controlled by the area of the interface and, therefore, the use of nanoparticle layers may greatly accelerate the rate of the overall process.

中文翻译：

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耦合扩散过程的时空可变扩散率 (STVD) 方法

摘要 在混合阶偏微分方程理论中构建了耦合扩散过程模型。它的数值实现是通过一种技术来实现的，该技术不需要超出扩散方程解的标准程序的额外工具。在扩散过程的大部分过程中，扩散剂和基材之间的界面保持其清晰度。结果表明，正如在药物和扩散键合应用中所预期的那样，可用于扩散的材料量受界面面积控制，因此，使用纳米颗粒层可以大大加快整个过程的速度。