Noun
(initialism) (common) Parts per million. (10000 ppm = 1%)
(initialism) page(s) per minute
Initialism of pulse position modulation.
Initialism of process production model.
Initialism of power-performance management.
Initialism of prediction by partial match.
PPM (plural PPM)
Initialism of page per minute.
We run enormous risks and we know what kind of reductions of greenhouse gases are necessary to drastically reduce risks. Reducing emissions by half by 2050 is roughly in the right ballpark. It would bring us below 550 ppm. Nicholas Stern
1,4-Dioxane contamination Some products containing SLES have been found to also contain traces (up to 279 ppm) of 1,4-dioxane ; this is formed as a by-product during the ethoxylation step of its synthesis. Source: Internet
1 H NMR chemical shifts for diamagnetic organotransition-metal compounds is usually observed between 25 and 40 ppm, but this range is much more narrow for diamagnetic metallocene complexes, with chemical shifts usually observed between 3 and 7 ppm. Source: Internet
A change in frequency of one vibration in 21,000 for each °F (86 ppm per °C) change is typical for a steel tuning fork. Source: Internet
A metre was originally defined as the 10-millionth part of the length of a meridian (the target was not quite reached in actual implementation, so that is off by 200 ppm in the current definitions). Source: Internet
Ammonia is an irritant and irritation increases with concentration; the Permissible Exposure Limit is 25 ppm, and lethal above 500 ppm. Source: Internet