x≥0(a10,av0》 OB线:升华线,冰的饱和蒸汽压曲线 H0(s)→H20(g) (岁an(a0A0) △>AwL(s>那n 18 18 ( ) 0 = vap m vap m OA T V H dT dP OB 线:升华线,冰的饱和蒸汽压曲线 H2O(s)→H2O(g) ( ) 0 = sub m sub m OB T V H dT dP ΔsubHm > Δ vapHm OB OA dT dP dT dP ( ) ( ) (ΔHm >0,ΔVm >0) (ΔHm >0,ΔVm >0)