narrow-beam absorption coefficient

例句：

1. 1.The absorption coefficient of the material is crucial for its performance.
   该材料的吸收系数对其性能至关重要。
2. 2. The absorption coefficient of the gas is affected by the temperature and pressure.
   气体的吸收系数受温度和压力的影响。
3. 3.The absorption coefficient of the material can be optimized to improve its performance.
   可以通过优化材料吸收系数来提高其性能。