How did the smog come from? List of preparation before class

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.

There are several reasons for the smog weather.

1, low pressure and no airflow are the main factors. Because the air does not flow, the tiny particles in the air gather and float in the air.

2. The ground is dusty, the air humidity is low, and the dust stirred up by people and traffic on the ground.

3. Automobile exhaust is the main pollutant emission.

4. Secondary pollution produced by factories.

5. CO2 and other pollutants emitted by heating in winter.

6. Urban buildings are getting taller and denser, which not only makes the air not like to circulate when the air pressure is low, but also makes it worse. Moreover, the tension generated by the building surface will contribute to the formation of smog.

7. There are fewer and fewer floors in the city that can produce capillary phenomena, so that not only dry fine particles on the ground are easy to form smog, but also the smog particles are not easily absorbed by the ground, so that the smog will rise and fall, leading to circulation and difficult to cure.

Haze will do harm to people's health;

1. Effects on respiratory system. The composition of smog is very complex, including hundreds of atmospheric chemical particles. Among them, aerosol particles smaller than 10 micron are harmful to health, such as mineral particles, sea salt, sulfate, nitrate, organic aerosol particles, fuel, automobile exhaust, etc., which can directly enter and adhere to human respiratory tract and alveoli. In particular, submicron particles will be deposited in the upper and lower respiratory tract and alveoli respectively, causing acute rhinitis and acute bronchitis. For patients with chronic respiratory diseases such as bronchial asthma, chronic bronchitis, obstructive emphysema, and chronic obstructive pulmonary disease, smog weather will make the condition acute or acute. Staying in this environment for a long time will also induce lung cancer.

2. Influence on cardiovascular system. There are many pollutants in the air in foggy days, and the air pressure is low, which is easy to induce acute attacks of cardiovascular diseases. For example, when the fog is heavy, the water vapor content is high. If people exercise outdoors, the sweat of human body is not easy to be discharged, which causes people to feel chest tightness and blood pressure to rise.

3. Hazy weather will also lead to the weakening of ultraviolet rays in the surface layer, which can enhance the activity of infectious bacteria in the air and increase infectious diseases.

4. In foggy days, due to the decrease of sunshine, children's ultraviolet radiation is insufficient, vitamin D production in the body is insufficient, and the absorption of calcium is greatly reduced, which will seriously cause rickets in infants and children, and slow down the growth and development of children.

5. Affect mental health. The gloomy and foggy weather is prone to mental laziness, depression and pessimism due to the weak light and low air pressure, and even it is easy to get out of control at the slightest sign of trouble.

Therefore, go out as little as possible in foggy days. If you go out, you should be well protected. On this day, Puweixin, a cat imported from America, will help you reduce smog inhalation. I wish you the best of health!