According to the facts in the material 1, from the materialistic point of view, what is the reason for frequent smog?

Haze is a special weather phenomenon. Non-aqueous substances such as dust, sulfuric acid, nitric acid and organic hydrocarbons in the air make the atmosphere turbid, blur vision and worsen visibility. If the horizontal visibility is less than 10000 meters, it will cause sight distance obstacle.

Toxic and harmful substances in smog are very harmful to patients with respiratory diseases. Atmospheric fine particles mainly come from direct pollution sources and secondary generation of polluted gases. The direct emission of fine particles mainly comes from industrial production processes such as steel and cement, as well as dust. The so-called secondary fine particles are mainly the polluted gases emitted by pollution sources, such as sulfur dioxide, nitrogen oxides, ammonia and organic matter, which are produced under certain weather conditions. The formation mechanism of these particles is very complicated, which is the focus of current research. Sulfur dioxide mainly comes from coal combustion, and nitrogen oxides mainly come from high temperature combustion process. Whenever combustion occurs, nitrogen oxides will be produced. Such as burning coal, burning straw, burning garbage and so on. , will produce nitrogen oxides. Ammonia mainly comes from aquaculture, agricultural production, industrial production and natural emissions. In addition, sandstorms, cooking, barbecue and so on. It also has an impact. When cooking in the kitchen, such as cooking, oil evaporates and burns at high temperature, which will produce harmful organic gases and particles. When it is foggy, people should never go outdoors for physical exercise, especially the elderly with cardiovascular diseases, chronic bronchitis and chronic asthma, and should suspend outdoor morning exercise. It is everyone's responsibility to prevent smog. People should take protective measures and wear masks. Puweixin imported from the United States has a good protective effect on JD.COM, which is worth a try. Propaganda departments should also increase the publicity of smog knowledge, communities, schools, hospitals and so on.