Nitrogen oxides (NOX.) are produced when fuel is burned at very high temperatures.

氮氧化物(NOX)产生于高温下的燃料燃烧。

youdao

The technology of exhaust gas recirculation (EGR) has been researched in a turbocharged direct-injected diesel engine in order to reduce Nitrogen Oxides (NOX) emission.

针对增压直喷柴油机，开展了应用废气再循环（EGR）技术降低氮氧化物（NOx）排放的研究。

youdao

In Europe the trucking industry has settled on a technology called selective catalytic reduction, in which urea is periodically injected into the exhaust system to break down the NOx, converting nitrogen oxides into (somewhat) harmless ammonia.

FORBES: Clearing the Air

These include the exhaust gases such as nitrogen oxides (NOx), non-methane volatile organic compounds (NMVOCs), and carbon monoxide (CO).

BBC: London's clue to stubborn ozone levels

These gases are then used to clean up smog-producing nitrogen oxides, or NOx.

FORBES: Clearing the Air