particulate mass analyzer

例句：

1. 1. The particles in the air are causing health problems for many people.
   空气中的颗粒物给许多人带来了健康问题。
2. 2. The particles in the soil can affect plant growth.
   土壤中的颗粒物会影响植物生长。
3. 3. The particles in the water were too small to be seen with the naked eye.
   水中的颗粒太小，肉眼无法看见。