At the end of the 19th century, the smog in Europe became more and more severe, which invention of t

Smog is mainly composed of sulphur dioxide, nitrogen oxides and inhalable particulate matter. Haze is made up of particles in the air, such as dust, sulfuric acid, nitric acid, organic hydrocarbons, etc.

It can also muddy the atmosphere, blur the field of view and lead to worsening visibility, and if the horizontal visibility is less than 10,000 meters, the visual range obstruction caused by this non-aqueous aerosol system is called haze or haze, which is called haze by the Hong Kong Observatory.

Hazards of smog:

1. Harm to the human body:

1) Effects on the respiratory system.

The composition of haze is very complex and includes hundreds of atmospheric chemical particulate matter. Among them, the main health hazards are aerosol particles with a diameter of less than 10 microns, such as mineral particles, sea salt, sulfates, nitrates, organic aerosol particles, fuels and automobile exhaust gases, which can directly enter and adhere to the human respiratory tract and alveoli.

2) Effects on the cardiovascular system.

The impact of haze on human cardiovascular and cerebrovascular diseases is also very serious, which will hinder normal blood circulation, lead to cardiovascular disease, hypertension, coronary heart disease, cerebral hemorrhage, may induce angina, myocardial infarction, heart failure, etc., and make chronic bronchitis cause cor pulmonale.

The above content reference: Encyclopedia - Haze.

In recent years, the main components of smog in China are sulfur dioxide, nitrogen oxides, and inhalable particulate matter.

Smog is the result of the interaction of specific climatic conditions with human activities. The economic and social activities of high-density populations will inevitably emit a large amount of fine particulate matter (pm, once the emission exceeds the atmospheric circulation capacity and carrying capacity, the concentration of fine particulate matter will continue to accumulate, and if affected by static weather, it is very easy to appear large-scale haze.

Smog is mainly composed of sulphur dioxide, nitrogen oxides and inhalable particulate matter, the first two of which are gas-friendly pollutants, and the latter particulate matter is the main cause of haze weather pollution, which combines with fog to make the sky instantly gloomy and gray.

The English abbreviation for Particulate Matter is PM, and Beijing monitors fine particulate matter, which is pollutant particles with an aerodynamic equivalent diameter of less than or equal to microns. The pellet itself is not only a pollutant, but also a carrier of toxic substances such as heavy metals and polycyclic aromatic hydrocarbons.

If the landlord asks when the smog appeared, it has actually been recorded a long time ago, and the specific state can be traced back to the Yuan Dynasty.

In 1481, due to the lack of rainfall, "the wind blew fiercely for several days, and the dust covered the air".

In 1485, the drought caused the hungry people near Beijing to pour into the capital to seek food, and the city was often stormy and strong, and the history books called "the wind and haze tired".

In 1493, "Jingshi rain haze", if the landlord wanted to ask the time when the haze attracted attention, it was first proposed by Locke Jiahui and aroused heated discussions among the Chinese people.

Hope to help the landlord.