强度量：intensive properties do not depend on mass （e,g,p,=1/,u and h ）,extensive properties depend on the total mass of the system（e,g,V,M,U,and H）.Uppercase letters are usually used for extensive properties.准平衡：equilibrium：states of a system are most conveniently described when the system is in equilibrium, i.e. it is in steady-state.Often we will consider process that change “slowly”-termed quasi-equilibrium or quasi-static process.A process is quasi-equilibrium if the time rate of change
