Student Research: Chunmei Fu
Airborne particulate matter (PM) is a complex mixture of solid particles and liquid droplets of different size, composition, origins, and chemical makeup. Particulate matter with a diameter of 10 micrometers of less in size is referred to a PM10 and particulate matter with a diameter of 2.5 micrometers or less in size is referred to as PM2.5. PM2.5 and PM10 differ in the type of mechanism that foRMS them, as well as chemical composition, solubility, acidity, exposure relationship, and atmospheric lifetime. PM10 consists mainly of organic material, silicates, and larger soot aggregates. PM2.5 comes from incomplete fuel combustion from motor vehicles, power generation, and industrial facilities, as well as residential wood stoves and fireplaces. Fine PM can also be created when gases such as sulfur dioxide react with volatile organic compounds in the air and form new particles. These newly created particles are referred to as secondary PM (EPA, 1996).
Taken from the beginning of thesis.