Nitrogen oxides diesel combustion

Daimler-Benz has accumulated data on NECAR III emissions with a dynamometer programmed for a mix of urban and suburban driving. The results were promising since there were zero emissions for nitrogen oxide and carbon monoxide, and extremely low hydrocarbon emissions of only. 0005 per gram per mile. NECAR III did produce significant quantities of carbon dioxide similar to the emissions of a direct-injection diesel engine where the fuel is injected directly into the combustion chamber. Direct-injection produces less combustion residue and unburned fuel. 

What is the cause of this acid rain The combustion of fossil fuels (gas, oil, and coal) by power plants produces oxides of sulfur and nitrogen. Nitrogen oxides, in excess of normal levels, arise mainly from conversion of atmospheric nitrogen to nitrogen oxides in the engines of gasoline and diesel powered... 

An important vehicle for public transportation is the city bus, usually fuelled by diesel oil. Combustion of diesel oil causes environmental problems, such as emissions of soot particles, polyaromatic compounds, hydrocarbons, nitrogen oxides and sulfur oxides. To address air pollution problems in the Swedish big city areas, local transport companies have set up fleet tests with alternative-fuelled vehicles. One example is the gas buses in Gothenburg fuelled by compressed natural gas. In Stockholm, Stockholm Transport has a fleet test with 32 ethanol buses (Ryden and Berg, 1991). This is the largest fleet test of its kind in the world. 

---