扩散原是一个物理学概念。它是指由于微粒(分子、原子等)的热运动而产生的物质迁移现象。物理上是指一种物质从浓度较高的区域向浓度较低的区域转移的现象和过程。扩散过程的结果是该物质在介质中的均匀分布。如氨在静止空气 Diffusion was originally a concept of physics. It refers to the phenomenon of material migration due to the thermal movement of particles (molecules, atoms, etc.). Physically refers to the phenomenon and process of the transfer of a substance from a higher concentration area to a lower concentration area. The result of the diffusion process is the uniform distribution of the substance in the medium. Such as ammonia in still air