一、引言物质体系中存在状态函数熵这一事实是自然界最深刻的规律之一。熵函数是由热力学第二定律导出的。在其推导方法中,严格的方法有两个,一是Carnot循环法,一是公理化方法。 Carnot循环法是由研究热机效率的Carnot定理,经过抽象推理得到熵的定义式和熵增加原理。从 I. INTRODUCTION The fact that there is a state function entropy in the material system is one of the most profound laws in nature. The entropy function is derived from the second law of thermodynamics. Among its derivation methods, there are two strict methods. One is the Carnot cycle method and the other is the axiomatic method. The Carnot cycle method is based on Carnot’s theorem for the study of heat engine efficiency. Through abstract reasoning, the definition of entropy and the principle of entropy increase are obtained. From