R-Cp.m-Cvm Ln T T Cpm C 1313 R=Cp,m - Cv,m 积分：Cv,mln( 1 2 T T ) =Rln( 2 1 V V ) 1 2 T T = 1 2 1 ( )  − V V 2 1 2 1 , , , 1 2 ( 1) V V Ln V V Ln C C C T T Ln V m P m V m = − − =  V P V m P m C C C C = = , , 