The detection principle of the nitrogen oxide detector.

The key component of the nitrogen oxide detector is the gas sensor. In principle, gas sensors can be divided into three categories:

a) Gas sensors using physical and chemical properties: such as semiconductor type (surface control type, volume control type, surface potential type), catalytic combustion type, solid heat conduction Type etc.

B) Gas sensors using physical properties: such as heat conduction type, light interference type, infrared absorption type, etc.

C) Gas sensors using electrochemical properties: such as constant potential electrolysis, Gawani battery, diaphragm ion electrode, fixed electrolyte, etc.

The nitrogen oxide detector can effectively monitor nitrogen oxide emissions, thereby reducing accidents. Nitrogen oxides, mainly nitric oxide and nitrogen dioxide, are an important cause of photochemical smog and acid rain. The toxic smog formed by the reaction of nitrogen oxides in automobile exhaust with nitrogen and hydrogen compounds under ultraviolet radiation is called photochemical smog. Photochemical smog has a special smell, irritates the eyes, harms plants, and reduces the visibility of the atmosphere. In addition, nitric acid and nitrous acid produced by the reaction of nitrogen oxides in the air with water are components of acid rain. Nitrogen oxides in the atmosphere mainly come from the burning of fossil fuels and the burning of plants, as well as farmland soil and soil