焓

例句：

1. 1. The engine's efficiency is measured by the enthalpy of its heat source.
   发动机的效率由其热源的焓来测量。
2. 2. The process of converting solar energy into electricity involves a significant amount of enthalpy.
   将太阳能转换为电能的过程涉及大量的焓。
3. 3. Thermal conductivity is a measure of how much enthalpy can be transferred through a material.
   热导率是衡量材料能传递多少焓的指标。