Preface -Physical properfies of gas 米组成，n Composition moles 米 压力，卫 Pressure -Pa 米体积，V Volume-m3 Ah 米温度，T Temperature -K Xi’an University of Science & Technology Preface -Physical properties of gas  组成, n Composition - moles  压力, p Pressure – Pa  体积,V Volume - m3  温度,T Temperature - K