△S=△S1+△S2+AS3 △S= T CPm dT T C7+ pm dT T 55 ΔS =ΔS1 +ΔS2 +ΔS3 ΔS1 = dT T T CP m 0 , = dT T T CP m  * 0 * , + dT T T C T P m  1 * , （T * <15K） = dT T T CV m  * 0 * , + dT T T C T P m  1 * , C*V，m = 1944 3 ( )  T