文档介绍：This manuscript was revised by the office on December 10, 2020.
建环专业英语
建筑环境与设备工程专业英语翻译
A thermodynamic syof energy, and enthalpy.
Frequently, thermodynamic properties combine to form other properties. Enthalpy h, a result of combining properties, is defined as: h=u+pv where u is the internal energy per unit mass
系统属性是系统的任何观察到的特征。系统状态的定义是通过列出其属性。最常见的热力学性质的温度T，压力P，和特定的体积V或密度ρ。其他热力学性质包括熵，能量储存形式，和焓。
通常情况下，热力学性质相结合，形成其他属性。焓H，一个属性相结合的结果，被定义为：H = U + PV
其中u是每单位质量的内部能量
Each property in a given state has only one definite value, and any property always has the same value for a given state, regardless of how the substance arrived at that state.
A process is a change in state that can be defined as any change in the properties of a system. A process is described by specifying the initial and final equilibrium states, the path (if identifiable), and the interactions that take place across system boundaries during the process.
一个给定的状态的属性只有一个定值，和任何财产总是有相同的值给定的状态，不管物质如何达到那种状态。
一个进程是一个状态的改变，在系统属性的任何改变，可作为定义。一个过程是指定的初始和最终的平衡状态，路径（如果识别），并采取跨系统的边界，在这个过程中发生的相互作用。
A pure substance has a homogeneous and invariable chemical composition. It can exist in more than one phase, but the chemical composition is the same in all phases 一个周期进程的一个过程或一个系列，其中系统的初始和最终状态是相同的的。因此，在一个周期结束时，所有属性具有相同的价值
纯物质具有均匀的和不变的化学成分。它可以存在于超过一个阶段，但在各个阶段的化学成分是一样的
liquid. If the temperature of the liquid is lower than the saturation temperature for the existing pressure, it is called either a subcooled liquid (the temperature is lower than the saturation temperature for the given pressure) or a compressed liquid (the pressure is 如果一种物质在饱和温度和压力的液体，它被称为饱和液体。如果液体的温度低于现有的压力的饱和温度，它被称为是过冷液体（温度低于给定压力的饱和温度）或压缩液体（压力大于饱和为给定的温度压力）。
exists as a vapor at saturation temperature and pre