How Can Industrial Upgrading Improve China's Air Quality —Empirical Analysis Based on Multilevel Growth Model

: With the rapid development of industrialization and urbanization in China, 11 the ecological environment has been damaged, especially the air quality, which has 12 brought troubles to the production and life of residents. China has taken various 13 measures to improve air quality, and industrial upgrading is one of the measures. How 14 can industrial upgrading improve air quality? This article uses the urban and 15 provincial data from 2015 to 2018, adopts a multilevel growth model, and draws the 16 following conclusions through empirical analysis.Companies aiming at economic 17 profit and survival will eventually lead to overall industrial upgrades that have little 18 effect on air improvement.Industrial structure adjustment under the effect of industrial 19 upgrading can reduce air pollution and have a significant impact on the improvement 20 of air quality.Industrial upgrading under the effect of time will inevitably reduce the 21 impact on environmental pollution, which is conducive to the improvement of air 22 quality.According to the empirical results, this paper puts forward some suggestions 23 to improve the air quality.


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Reform and opening up and the implementation of the market system have 27 2 created opportunities for China's development and promoted rapid economic 28 growth.However, the rapid economic growth is at the cost of heavy environmental 29 pollution. The ecological environment has been destroyed, and air pollution is 30 particularly serious.China's air pollution is on the rise before 2013 (Li et al,2018).It 31 has a great impact on Residents' health and travel (Kenneth,2003 University and other research units shows that China ranked 137th with an air quality 41 score of 27.1 among 180 countries (Wendling et al.,2020).Improving air quality is still 42 one of the main problems in China. 43 China is a developing country with a relatively rapid process of industrialization 44 and urbanization, with a more extensive growth pattern and more serious 45 environmental pollution.The influencing factors of air pollution are various, and the 46 process of industrialization is one of the main causes of air pollution. He(2015) 47 analyzed the causes of haze pollution and found that the over-heavy industrial 48 structure was the main cause, and emphasized that air pollution is closely related to 49 3 industrial development.The high proportion of regional industrial structure will cause 50 strong regional pollution emissions and affect air quality .Air    upgrading and air quality, and make the conclusions more stable and reliable. index to measure air quality.The air quality index ranges from 0 to 500. The larger the 131 value, the higher the degree of air pollution.When the air quality index is less than 132 100, there is no significant impact on human health. When the air quality index is 133 greater than 100, it has various effects on human health.Therefore, this study uses air 134 quality index to represent air quality.The air quality index is urban data.

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The core explanatory variables are industrial structure adjustment (Isa) and   Industrial upgrading means that as the economy grows, the proportion of the three 144 industries continues to rise along the order of the first, second, and third industries.

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According to its calculation standard, the larger the value, the higher the level of    According to Figure 1, the setting form of the multilevel growth model is as 175 follows.The first layer is linear growth model, Where, AQI represents urban air quality. T represents the time variable. i represents 178 different cities in China. j represents different provinces.  The second layer is the city model.The core explanatory variable of the second 183 layer is industrial structure adjustment.If q=1 in Figure 1, the form of the city model is 184 as follows, Where, a Is is industrial structure adjustment.
The explanatory variable in formula (10) is related to the random disturbance      Figure 2 shows that linear growth models should be used.

Robustness test 351
In order to ensure the reliability of the research results, a robustness test is now 352 carried out.In this paper, the dependent variable is changed to pm2.5, and a multilevel 353 linear growth model is used for estimation. The results are shown in Table 3.It can be 354 seen from Table 3   According to the empirical results, this paper draws three conclusions.

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The first is that industrial upgrading itself has no significant impact on air   has a significant effect on the improvement of air quality, indicating that time reflects 412 a long-term trend.If the long-term trend aims at improving and perfecting the sharing 413 mechanism for the whole people, it will help eliminate the dual structure of urban and 414 rural areas, improve the level of human capital, and improve the quality of the whole 415 people.When the whole people at a higher level no longer pay attention to food and 416 clothing issues, but pay attention to the quality of life, it will lead to high-quality 417 economic development.High-quality economic development will put environmental 418 protection in a more important position, and the air quality closely related to residents 419 will be greatly improved.    435 All authors declare that there is no competing interests in this paper.

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Availability of data and materials 437 The raw data used to support the findings of this study.The raw data comes from