The Nox Reduction System is a state-of-the-art emission control technology designed to drastically reduce nitrogen oxides (Nox) emissions in a wide range of industrial and automotive applications.At the core of this system its sophisticated catalysts and procedures control systems which are combined to transform the harmful oxide nitrogen into environmentally friendly nitrogen and oxygen gases.The air pollution sources include smoke stacks from oil refineries, waste incinerators and coal-fired power plants.That is why this study undertaken in Shanghai, a representative model of China's worst urban air pollution.Top-level design was applied to the scientific research project called A Demonstration of Clean Air Technology, which looked at Shanghai's environmental quality under various conditions over one year periods but for all its efforts, improving measurement levels such as sulfur dioxide (SOz) by 80% and Particulate Matter 94%.Technological features include selective catalytic reduction (SCR) technology, advanced sensors for monitoring Nox levels, and control units that optimize the reduction process.This system is used mostly in power stations, heavy machinery or vehicles with diesel engines.It helps to meet stringent environmental regulations and at the same time cuts down on the carbon footprint.