The main source of photochemical smog is

The main sources of photochemical smog are as follows:

1. The main sources of photochemical smog are primary pollutants such as hydrocarbons (ch) and nitrogen oxides (nitrogen oxides) discharged into the atmosphere by pollution sources such as automobiles and factories, which react chemically under the action of sunlight to generate secondary pollutants such as ozone (O3), aldehydes, ketones, acids and peroxyacetyl nitrate (PAN).

2. Photochemical smog is an irritating reddish-brown smog, which consists of ozone and aldehydes, as well as nonmetallic oxides such as sulfuric acid, nitric acid and organic hydrocarbons. The sources of these substances are mainly the secondary pollutants ozone and trihalomethane produced by artificial emission of fluorine-containing hydrocarbons and oxygen-containing organic compounds in nature after illumination.

3. The formation of photochemical smog is also related to meteorological conditions. In the summer and autumn with strong sunshine, the primary pollutants such as nitrogen oxides and hydrocarbons emitted by automobiles and factories react chemically under the action of sunlight to generate secondary pollutants such as ozone, aldehydes, ketones, acids and peroxyacetyl nitrates.

4. These secondary pollutants gather together to form photochemical smog, which seriously affects human health and ecological environment. Photochemical smog is not only a kind of harmful gas pollution, but also irritates eyes and throat, causing visual and respiratory discomfort, and may lead to asthma, allergies and other diseases in severe cases.

5. The pollution degree and concentration of photochemical smog are related to meteorological conditions such as temperature, humidity, wind direction and wind speed. High temperature, high humidity, low wind speed and strong sunshine will all promote the formation of photochemical smog. Therefore, photochemical smog pollution is the most serious in summer and autumn, especially in sunny weather conditions.

The relevant knowledge of smog is as follows:

1.Smoke is a compound word of soot and fog, which was created and used by British Vajk in 1905. Smoke is a mixture of many pollutants, including dust, gas and liquid particles. These pollutants may be man-made sources, such as industrial emissions, automobile exhaust, combustion products, or natural sources, such as volcanic eruptions and forest fires.

2. These pollutants will not only irritate the eyes, throat and other parts, but also cause health hazards to human beings and the ecological environment, such as asthma, allergies and poor plant growth.