Smog, also known as PM2.5, is a kind of inhalable particulate matter harmful to human body. Excessive inhalation can lead to upper respiratory tract infection, lung cancer and other diseases, and may also cause conjunctivitis and infantile rickets.
So, how is the smog formed? Haze is actually caused by automobile exhaust, chemical pollution, coal-fired emissions and other reasons. Sometimes cooking also produces a small amount of PM2.5
Smoke has done us great harm. Physical education class should be in the small classroom; Driving is easy to cause traffic accidents, so it is necessary to turn on fog lights; You can't see clearly when you walk, and it is easy to fall; Bring diseases to our bodies; In severe cases, visibility shall not exceed 50 meters.
Let's fight against smog and live a healthy life together.
A 3000-word paper on the formation and harm of smog (1) title, title)
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(2) the author's name and department.
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Hazards of smoke. Composition 1500 words. On Sunday, with the help of my father, I checked the air quality in Xi in the first half of March online. After the inspection, I was surprised. I found that China was heavily polluted for six days, lightly polluted for two days and moderately polluted for seven days.
It turns out that we live in such an environment. I asked my father, "Are smog and dust harmful to human body?" My father and I looked up the information on the Internet. It turns out that smog and dust are very harmful. Haze will lead to the spread of infectious diseases and the occurrence of various diseases, which will bring great harm to human health. Dust will also endanger people's health and bring great inconvenience to human travel.
I also checked the causes of smog and dust. It turns out that the air pressure in the atmosphere is low and stagnant air is the main factor. Stagnant air is the tiny particles in the air that gather together and float in the air. Due to the large dust on the ground and low temperature, people and vehicles on the ground are stirred up by dust ... Dust is a harmful weather phenomenon caused by the interaction of wind, rain and sand, and its formation is inextricably linked with global greenhouse effect, vegetation destruction, species extinction and climate anomaly. He is also divided into sandstorm, floating dust and strong dust. ...
I don't think we should exploit natural resources without restraint and cut down trees at will. People with cars should drive as little as possible, take more buses and ride more bicycles, and travel green. Try to use energy-saving lamps for light bulbs, turn on less air conditioning, and everyone should sprinkle more water on the street. Don't litter everywhere, plant more trees to protect our earth.
2、、、
This winter, the smog weather has attracted everyone's attention, and the smog is even more harmful. Several cities have won, so we should strengthen environmental management and not let smog weather wreak havoc.
Many people know the cause of smog. Of course, smog is composed of fog and haze. The main causes of fog are
Haze, haze, haze
This winter, the smog weather has attracted everyone's attention, and the smog is even more harmful. Several cities have won, so we should strengthen environmental management and not let smog weather wreak havoc.
Many people must know the cause of smog. Of course, smog is composed of fog and haze. The main cause of fog is an aerosol system composed of a large number of tiny water droplets or ice crystals suspended in the ground air, which is the product of water condensation in the near-ground air. Fog mainly reduces visibility and causes traffic hazards, but it does little harm to people.
Haze is composed of dust, sulfuric acid, nitric acid and other harmful substances in the air, which will make the atmosphere turbid, blur the line of sight, reduce visibility and do great harm to human body. In this way, fog and haze, two unrelated brothers, came together and caused unprecedented damage to the atmosphere. The air quality in some cities has reached the level of moderate pollution, and some cities have reached the level of severe pollution, which is very terrible.
Haze is very harmful, which will affect roads, railways, aviation, power supply systems and crop growth. It is also easy to lead to the spread of infectious diseases and the occurrence of various diseases. Endanger people's health. Moreover, it will make it difficult for pollutants in the air to diffuse, enhance the toxicity of harmful substances, and even lead to toxic fog in serious cases. And it will do great harm to people, especially to the respiratory system. It is reported that the number of people suffering from respiratory diseases this winter has increased by% 30-%40 compared with last winter. What an amazing number this is, which deserves our deep thought. Therefore, it is urgent to prevent haze weather.
Our preventive measures should be in place, and morning exercises and outdoor sports should be stopped in foggy days. That's not enough. I think the main reason for this bad weather is the emission of automobile exhaust and industrial production exhaust. Therefore, the state should introduce policies as soon as possible to manage and control the emission of harmful gases, plant more trees and grass, and purify our environment. I think, if everyone mobilizes, the foggy weather should run away despondently.
In short, I hope everyone can take action, plant more grass and flowers, protect the environment and create a green and natural environment for our future generations.
Hope to adopt
140' s composition on the hazards of smog seems to have created a kind of novel coronavirus's viability. SARS not only exceeded the initial estimate, but also did not gradually weaken several short-term mutations originally envisaged, so this dangerous virus needs more comprehensive evaluation experts and other institutions.
Previously, scientists had predicted that with the increase of the number of SARS virus, it would have the ability to mutate and lead to infection and weakened pathogenicity. However, they compared 14 viruses extracted from SARS patients around the world, and found that the genetic changes of SARS virus were much smaller than previously expected, and no mutation weakened its danger.
David heyman, Chief Executive Officer of Infectious Diseases of the World Health Organization, said that now they all agree that SARS virus has adapted well to human infection, and its infection is persistent. In addition, the stability of the virus means that people can develop more targeted treatments and vaccines, but the coronavirus family has always been very resistant, and the arduous task of scientists has been advanced.
Haze is the general term for fog and haze. It has an impact on the respiratory tract and cardiovascular system, and protective measures should be taken at ordinary times. Patients with cardiovascular diseases should minimize travel. Puweixin imports cats from the United States every day to prevent smog. Automobile exhaust, straw burning and workshop exhaust are all causes of smog, and it is everyone's responsibility to prevent smog.
Haze hazards, prevention and punishment. First of all, it is cold in winter, and coal-fired heating will emit a lot of smoke and dust into the air. In addition, people and traffic on the dry ground in winter will stir up dust, and a large amount of dust will act as condensation nuclei in the air, making the water vapor in the air condense into cloudy weather.
Secondly, automobile exhaust is the main pollutant emission. In recent years, there are more and more cars in cities, and automobile exhaust is a factor of smog.
Third, the discharge of "three wastes" and the secondary pollution produced by factories.
Haze can cause harm to people's respiratory system and cardiovascular system, so we should protect the environment and reduce travel in foggy days. Puweixin imported from the United States can effectively reduce smog inhalation!
Haze harms senior high school composition 1,,, Haze harms human body.
On Sunday, with the help of my father, I checked the air quality in Xi in early March online. After the inspection, I was surprised. I found that there were 6 days of heavy pollution, 2 days of light pollution and 7 days of moderate pollution in China.
It turns out that we live in such an environment. I asked my father, "Are smog and dust harmful to human body?" My father and I looked up the information on the Internet. It turns out that smog and dust are very harmful. Haze will lead to the spread of infectious diseases and the occurrence of various diseases, which will bring great harm to human health. Dust will also endanger people's health and bring great inconvenience to human travel.
I also checked the causes of smog and dust. It turns out that the air pressure in the atmosphere is low and stagnant air is the main factor. Stagnant air is the tiny particles in the air that gather together and float in the air. Due to the large dust on the ground and low temperature, people and vehicles on the ground are stirred up by dust ... Dust is a harmful weather phenomenon caused by the interaction of wind, rain and sand, and its formation is inextricably linked with global greenhouse effect, vegetation destruction, species extinction and climate anomaly. He is also divided into sandstorm, floating dust and strong dust. ...
I don't think we should exploit natural resources without restraint and cut down trees at will. People with cars should drive as little as possible, take more buses and ride more bicycles, and travel green. Try to use energy-saving lamps for light bulbs, turn on less air conditioning, and everyone should sprinkle more water on the street. Don't litter everywhere, plant more trees to protect our earth.
2、、、
This winter, the smog weather has attracted everyone's attention, and the smog is even more harmful. Several cities have won, so we should strengthen environmental management and not let smog weather wreak havoc.
Many people must know the cause of smog. Of course, smog is composed of fog and haze. The main cause of fog is an aerosol system composed of a large number of tiny water droplets or ice crystals suspended in the ground air, which is the product of water condensation in the near-ground air. Fog mainly reduces visibility and causes traffic hazards, but it does little harm to people.
Haze is composed of dust, sulfuric acid, nitric acid and other harmful substances in the air, which will make the atmosphere turbid, blur the line of sight, reduce visibility and do great harm to human body. In this way, fog and haze, two unrelated brothers, came together and caused unprecedented damage to the atmosphere. The air quality in some cities has reached the level of moderate pollution, and some cities have reached the level of severe pollution, which is very terrible.
Haze is very harmful, which will affect roads, railways, aviation, power supply systems and crop growth. It is also easy to lead to the spread of infectious diseases and the occurrence of various diseases. Endanger people's health. Moreover, it will make it difficult for pollutants in the air to diffuse, enhance the toxicity of harmful substances, and even lead to toxic fog in serious cases. And it will do great harm to people, especially to the respiratory system. It is reported that the number of people suffering from respiratory diseases this winter has increased by% 30-%40 compared with last winter. What an amazing number this is, which deserves our deep thought. Therefore, it is urgent to prevent haze weather.
Our preventive measures should be in place, and morning exercises and outdoor sports should be stopped in foggy days. That's not enough. I think the main reason for this bad weather is the emission of automobile exhaust and industrial production exhaust. Therefore, the state should introduce policies as soon as possible to manage and control the emission of harmful gases, plant more trees and grass, and purify our environment. I think, if everyone mobilizes, the foggy weather should run away despondently.
In short, I hope everyone can take action, plant more grass and flowers, protect the environment and create a green and natural environment for our future generations.
Hello, you can ask me, which is helpful.
The causes of smog formation and the similarity between fog and haze are all visual distance obstacles. However, the reasons and conditions for the formation of fog and haze are quite different. Fog is a large number of tiny water droplets or ice crystals floating in the air, and the formation conditions should have a high water vapor saturation coefficient. When fog appears, the relative humidity of air often reaches 100% or approaches 100%. With the daily change of air humidity, fog is more common or thicker in the morning and evening, and it becomes lighter or even disappears during the day. The effective horizontal visibility is less than 1KM in fog. When the effective horizontal visibility is 1- 10km, it is called light fog.
"There is actually a difference between fog and haze." Sun Leng, a senior engineer in the Climate System Monitoring Office of the National Climate Center, pointed out that fog refers to the weather phenomenon when the visibility is lower than 1 km due to the condensation of suspended water vapor in the atmosphere. The formation of smog is mainly the result of a large number of suspended particles in the air and meteorological conditions. There are three reasons:
-The phenomenon of static wind in the horizontal direction has increased. The higher the buildings are built in the city, the obstruction and friction of airflow passing through the urban area will be obviously weakened. The increase of static wind phenomenon is not conducive to the diffusion and dilution of suspended particles in the atmosphere, and it is easy to accumulate around urban areas and suburbs;
-There is an inversion in the vertical direction. The inversion layer is like a pot cover over a city. This inversion phenomenon that the upper air temperature is higher than the lower air temperature limits the vertical movement of the lower air, making it difficult for suspended particles in the air to drift to the upper air and be blocked at the lower air and near the ground. The increase of suspended particles in the air. With the growth of urban population and industrial development, the number of motor vehicles has soared, and the emissions of pollutants and suspended solids have increased greatly, which directly leads to the decline of visibility.
Causes, hazards and elimination methods of smog. 1, the cause of smog
The influence of smog is long-term, and the reason for its formation is also a long-term and complicated process. Meteorologists pointed out that the formation of haze weather is not only affected by meteorological conditions, but also related to the increase of air pollutant emissions. With the growth of urban population and industrial development, the number of motor vehicles has soared, resulting in a large increase in pollutant emissions and suspended solids, which directly leads to a decline in visibility. The formation of smog is mainly the result of a large number of suspended particles in the air and meteorological conditions. There are three reasons for the formation of haze weather:
(1) The phenomenon of static wind in the horizontal direction increases.
(2) There is inversion in the vertical direction.
(3) The increase of suspended particles in the air.
(4) With the growth of urban population, the development of industry and the rapid increase of motor vehicles, the emissions of pollutants and suspended solids have greatly increased, which directly leads to the decrease of visibility. In fact, dust "smog" will also occur in home decoration, and indoor dust is pervasive, which is not only harmful to the health of staff and users, but also increases the cleaning burden. When the dust is serious, it will also bring many hidden dangers to the decoration project.
(5) The increase of atmospheric particulate matter (including coarse particulate matter PM 10 and fine particulate matter PM2.5) caused by industrial production, vehicle exhaust emission and coal burning in winter is an important factor of smog. At present, the level of pollutant discharge in many cities is at a critical point, which is very sensitive to meteorological conditions. When diffusion conditions are good, the air quality can reach the standard, and once adverse weather conditions are encountered, the air quality and visibility will drop rapidly.
(6) Coupled with the invasion of cold air in autumn and winter, the vertical movement of the air in the low altitude is restricted, and the suspended particles in the air are difficult to drift to the high altitude, which is blocked at the low altitude and near the ground. Several reasons are superimposed, causing smog.
2. Hazards of smoke
Pm2.5 is closely related to smog and has a great influence on human body. PM2.5 will penetrate the protective structure of respiratory tract, penetrate into bronchi and lungs, directly affect the ventilation function of lungs, induce pulmonary sclerosis, asthma and bronchitis, and lead to cardiovascular diseases; PM2.5 particles can carry viruses, bacteria, radioactive dust and heavy metals in the air, which have a serious impact on respiratory system, cardiovascular system, immune system, fertility, nervous system and heredity. Weaken people's collective resistance and induce the onset of cancer. It seriously hinders the development of children's lung function and accelerates the death of the elderly with weak constitution.
3. Solutions to smog
Smog control methods are mainly managed from three aspects: individuals, enterprises and * * * *.
The first law of smog control: personal departure. Increase the conservation, publicity and protection of resources, guide everyone around us to practice a low-carbon lifestyle, make a contribution to environmental protection, and make great gains when energy is gathered!
The second way to control smog: corporate governance
(1) Change the dust control mode, from dust removal to dust suppression, from organized to unorganized.
(2) From dust removal to dust suppression. Traditional dust removal technology has many disadvantages, such as secondary pollution caused by water dust removal, unstable effect caused by filter material adhesion, high cost caused by electrostatic dust removal and so on.
(3) From organized to unorganized. Organized emissions mainly exist in perfect and standardized workplaces; Unorganized emission plays an important role in air pollution in China. Therefore, we need to change the governance model. The existing BME biomembrane dust suppression technology, cloud dust suppression technology, wet dust removal technology and BME unorganized emission technology can be used for unorganized treatment.
Smog control method 3: * * control
(1) We should * * promote scientific and technological innovation, actively develop new energy sources, and encourage people to actively use new energy sources instead of letting fossils become the main fuel!
(2) *** Implement scientific development strategy and strengthen environmental protection!