Polymers, including natural proteins (such as DNA) and artificial materials (such as nylon and polyester), are examples of macromolecules. materials scientist Someone who studies the ways in which the atomic and molecular structure of a material relates to its overall properties.
Emission standards for engines and vehicles, including emission standards for greenhouse gas (GHG) emissions, are established by the US Environmental Protection Agency (EPA).The EPA authority to regulate engine emissionsâand the air quality in generalâis based on the Clean Air Act (CAA), most recently amended in 1990.ther states have a choice to either implement the federal emission standards, or else to adopt California requirements (CAA section 177).
Additionally, the Illinois Vehicle Emissions Inspection Law of 2005 (625 ILCS 5/13C) requires a vehicle emissions inspection program to reduce air pollution from motor vehicles in these areas of Illinois.