ppm
发音
How to pronounce ppm in British English:
英 ['pi:p'i:'em]
How to pronounce ppm in American English:
美 ['pip'i'em]
单词词源
- ppm
- abbreviation of parts per million, attested by 1913.
双语例句
- 1. Concentrations of 10 ppm can be endured for only a few minutes and cause profuse lacrimation in all people .
- 2. It has a repulsive acidic odor that can usually be detected at or below a concentration of 5 ppm .
- 3. Type I Diabetes mellitus usually starts from adolescent , whose morbidity rate is about 83 ppm and still increases .
- 4. By chance , oryza sativa is a like aluminum plant , its optimum concentration is 30 ppm was observed .