(3)等压过程 Q=Cpm(T1-10)=vR(71-70)=(D1-P0V0) E=V T=-VRT , 55 14206 1 0 7 11 V = V 1 , 1 1 1 1 2 2 pV i RT i E =Cv m T =  = （3）等压过程 ( ) 2 7 ( ) 2 7 ( ) Q =CP,m T1 −T0 = R T1 −T0 = p1 V1 − p0 V0 0 0 0 0 14 55 7 11 2 5 = p  V = p V