Basic concept 1.系统( Thermodynamic Systen):A quantity of matter or a region in space chosen for study. (系统就是指被选做研究对象的物体或空间。) 2.平衡状态( Equilibrium State) A system in equilibrium experiences no changes with time when it is isolated from its surroundings 所谓平衡状态就是指在没有外界影响的情况下,系统 的状态不随时间而发生变化。1. 系统 (Thermodynamic System): A quantity of matter or a region in space chosen for study. （系统就是指被选做研究对象的物体或空间。） 2. 平衡状态(Equilibrium State) A system in equilibrium experiences no changes with time when it is isolated from its surroundings. 所谓平衡状态就是指在没有外界影响的情况下，系统 的状态不随时间而发生变化。 Basic Concept