technical coefficient

例句：

1. 1.The coefficient of friction between the two materials is very high.
   两种材料的摩擦系数非常高。
2. 2.The coefficient of thermal conductivity is an important factor in determining the efficiency of a heat exchanger.
   热导率系数是决定换热器效率的一个重要因素。
3. 3. The coefficient of variation is used to measure the variability of data.
   变异系数用于衡量数据的变异性。