4. Talk about the hazards, causes and prevention measures of frequent dust and haze weather in China in recent years.

1/2 smog. But fog is fog, haze is haze, and the difference between fog and haze is very big.

Haze means haze. Dust, sulfuric acid and nitric acid in the air can cause vision damage. The difference between haze and fog is that the relative humidity is small when haze occurs, but it is saturated in fog (if there are a large number of condensation nuclei, the relative humidity may not reach 100%, and saturation may occur).

Sulfur dioxide, nitrogen oxides and inhalable particles are the main components of smog. The first two are gaseous pollutants, and the last particulate matter is the chief culprit that aggravates smog weather pollution.

2/2

Fog and haze are quite different in some ways.

For example, when fog appears, the air is humid; When smog occurs, the air is relatively dry and the relative humidity of the air is usually below 60%. The reason is that a large number of extremely fine dust particles, smoke particles and salt particles float in the air evenly, so that the air with effective horizontal visibility less than 10KM is mixed together. The symbol is "∞".

The diurnal variation of haze is generally not obvious. When the air mass changes little and is stable, it lasts for a long time, sometimes exceeding 10 days.

Due to weather phenomena such as haze, light fog, sandstorm, sand blowing, floating dust and smoke, the effective horizontal visibility is less than 10KM due to a large number of extremely fine dust particles or smoke particles floating in the air.

Hazards of smog

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Hazy days also have a serious impact on cardiovascular and cerebrovascular diseases, which will hinder normal blood circulation, lead to cardiovascular diseases, hypertension, coronary heart disease, cerebral hemorrhage, and may also induce angina pectoris, myocardial infarction and heart failure. And cause pulmonary heart disease in chronic bronchitis.

In addition, when the air pressure is relatively low in foggy weather, people will feel irritable and their blood pressure will naturally rise. On the other hand, in foggy days, the temperature is often low. Some patients with hypertension and coronary heart disease suddenly go from warm indoor to cold outdoor, and blood vessels expand with heat and contract with cold, which will also increase blood pressure, leading to stroke and myocardial infarction.

Control smog,

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Persistent foggy days have an impact on people's psychology and body. Psychologically speaking, foggy days will give people a feeling of depression, which will stimulate or aggravate the state of psychological depression.

In addition, due to the weak light and low air pressure in foggy days, some people will feel lazy and depressed in foggy days.

1/5

Wear a mask when you go out, go out as little as possible, and wash your bare skin immediately after you come back.

2/5

Close the doors and windows at home, pay attention to hygiene and moisturizing. To ensure the hygiene of the room, it is very important to be hygienic in foggy days, otherwise it will easily lead to respiratory diseases, and cleaning the soil that will not breed germs; Secondly, it is necessary to moisturize the room to ensure the relative humidity, so that floating dust can easily precipitate and adsorb on the ground, and try to wipe the dust with a wet rag to avoid being inhaled into the respiratory tract.

3/5

The diet is light and reasonable, and eat more foods that clear the lungs, such as black fungus porridge, pig blood spinach soup and so on.

4/5

Drink water frequently and don't stay up late.

5/5

It is easy to cause cardiovascular diseases, and the elderly cancel morning exercises.