ashless filter paper

例句：

1. 1.This ashless filter paper is very effective at removing dust and allergens from the air.
   这种无烟过滤纸非常有效地从空气中去除灰尘和过敏原。
2. 2.In hospitals, ashless filter papers are used to prevent the spread of infections in patient rooms.
   在医院，无烟过滤纸被用来防止病房内感染的传播。
3. 3.The engineers used ashless filter papers to create a clean and healthy environment for their patients.
   工程师们使用无烟过滤纸为他们的病人创造了一个干净而健康的环境。