ppm
noun[U]
uk/ˌpiː.piːˈem/us/ˌpiː.piːˈem/abbreviation forpartspermillion(= aunitformeasuringtheamountof asubstancethat ismixedwith aliquidor anothersubstance)
百万分之…（衡量物质与液体或其他物质混合时的度量单位，parts per million的缩写）Miscellaneous units of measurement
- acre
- acreage
- caloric
- curie
- dioptre
- farad
- fathom
- firkin
- flashpoint
- hectare
- Hz
- MHz
- millibar
- molar
- newton
- refractive index
- Scoville scale
- sievert
- torr
- watt