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1.
● China has pledged ambitious carbon peak and neutrality goals for mitigating global climate change. ● Major challenges to achieve carbon neutrality in China are summarized. ● The new opportunities along the pathway of China’s carbon neutrality are discussed from four aspects. ● Five policy suggestions for China are provided. China is the largest developing economy and carbon dioxide emitter in the world, the carbon neutrality goal of which will have a profound influence on the mitigation pathway of global climate change. The transition towards a carbon-neutral society is integrated into the construction of ecological civilization in China, and brings profound implications for China’s socioeconomic development. Here, we not only summarize the major challenges in achieving carbon neutrality in China, but also identify the four potential new opportunities: namely, the acceleration of technology innovations, narrowing regional disparity by reshaping the value of resources, transforming the industrial structure, and co-benefits of pollution and carbon mitigation. Finally, we provide five policy suggestions and highlight the importance of balancing economic growth and carbon mitigation, and the joint efforts among the government, the enterprises, and the residents.  相似文献   
2.
Xu  Peiwei  He  Xiaoqing  He  Shengliang  Luo  Jinbin  Chen  Qiang  Wang  Zuoyi  Wang  Aihong  Lu  Beibei  Wu  Lizhi  Chen  Yuan  Xu  Dandan  Chen  Weizhong  Chen  Zhijian  Wang  Xiaofeng  Lou  Xiaoming 《Environmental science and pollution research international》2021,28(6):6691-6699
Environmental Science and Pollution Research - To better understand the cardiopulmonary alterations associated with personal exposed PM2.5-bound heavy meals, we conducted a cross-sectional study in...  相似文献   
3.
• Aerosol transmission is an indispensable route of COVID-19 spread. • Different outbreak sites have different epidemiologic feature. • SRAS-CoV-2 can exist for a long time in aerosol. • SRAS-CoV-2 RNA can be detected in aerosol in diverse places. • Some environmental factors can impact SARS-CoV-2 transportation in aerosol. Patients with COVID-19 have revealed a massive outbreak around the world, leading to widespread concerns in global scope. Figuring out the transmission route of COVID-19 is necessary to control further spread. We analyzed the data of 43 patients in Baodi Department Store (China) to supplement the transmission route and epidemiological characteristics of COVID-19 in a cluster outbreak. Incubation median was estimated to endure 5.95 days (2–13 days). Almost 76.3% of patients sought medical attention immediately upon illness onset. The median period of illness onset to hospitalization and confirmation were 3.96 days (0–14) and 5.58 days (1–21), respectively. Patients with different cluster case could demonstrate unique epidemiological characteristics due to the particularity of outbreak sites. SRAS-CoV-2 can be released into the surrounding air through patient’s respiratory tract activities, and can exist for a long time for long-distance transportation. SRAS-CoV-2 RNA can be detected in aerosol in different sites, including isolation ward, general ward, outdoor, toilet, hallway, and crowded public area. Environmental factors influencing were analyzed and indicated that the SARS-CoV-2 transportation in aerosol was dependent on temperature, air humidity, ventilation rate and inactivating chemicals (ozone) content. As for the infection route of case numbers 2 to 6, 10, 13, 16, 17, 18, 20 and 23, we believe that aerosol transmission played a significant role in analyzing their exposure history and environmental conditions in Baodi Department Store. Aerosol transmission could occur in some cluster cases when the environmental factors are suitable, and it is an indispensable route of COVID-19 spread.  相似文献   
4.
电梯制动器是电梯最重要的安全部件之一,故研究其可靠性具有重要意义。首先分析了电梯制动器的故障机理并建立了动态故障树模型,其次利用二元决策图和马尔科夫方法对故障树进行了分析计算,得到了影响系统可靠性的相关指标以及制动器的薄弱环节,最后提出了改进措施和建议,为电梯制动器的设计、维修保养及检验提供了科学依据。  相似文献   
5.
Huang  Ying  Jiang  Qiongji  Yu  Xubiao  Gan  Huihui  Zhu  Xia  Fan  Siyi  Su  Yan  Xu  Zhirui  He  Cunrui 《Environmental science and pollution research international》2021,28(37):51251-51264
Environmental Science and Pollution Research - Trace copper ion (Cu(II)) in water and wastewater can trigger peroxymonosulfate (PMS) activation to oxidize organic compounds, but it only works under...  相似文献   
6.
The iron and steel industry is not only an important foundation of the national economy, but also the largest source of industrial air pollution. Due to the current status of emissions in the iron and steel industry, ultra-low pollutant emission control technology has been researched and developed. Liquid-phase proportion control technology has been developed for magnesian fluxed pellets, and a blast furnace smelting demonstration project has been established to use a high proportion of fluxed pellets (80%) for the first time in China to realize source emission reduction of SO2 and NOx. Based on the characteristics of high NOx concentrations and the coexistence of multiple pollutants in coke oven flue gas, low-NOx combustion coupled with multi-pollutant cooperative control technology with activated carbon was developed to achieve efficient removal of multiple pollutants and resource utilization of sulfur. Based on the characteristics of co-existing multiple pollutants in pellet flue gas, selective non-catalytic reduction (SNCR) coupled with ozone oxidation and spray drying adsorption (SDA) was developed, which significantly reduces the operating cost of the system. In the light of the high humidity and high alkalinity in flue gas, filter materials with high humidity resistance and corrosion resistance were manufactured, and an integrated pre-charged bag dust collector device was developed, which realized ultra-low emission of fine particles and reduced filtration resistance and energy consumption in the system. Through source emission reduction, process control and end-treatment technologies, five demonstration projects were built, providing a full set of technical solutions for ultra-low emissions of dust, SO2, NOx, SO3, mercury and other pollutants, and offering technical support for the green development of the iron and steel industry.  相似文献   
7.
Atmospheric oxidizing capacity (AOC) is an essential driving force of troposphere chemistry and self-cleaning, but the definition of AOC and its quantitative representation remain uncertain. Driven by national demand for air pollution control in recent years, Chinese scholars have carried out studies on theories of atmospheric chemistry and have made considerable progress in AOC research. This paper will give a brief review of these developments. First, AOC indexes were established that represent apparent atmospheric oxidizing ability (AOIe) and potential atmospheric oxidizing ability (AOIp) based on aspects of macrothermodynamics and microdynamics, respectively. A closed study refined the quantitative contributions of heterogeneous chemistry to AOC in Beijing, and these AOC methods were further applied in Beijing-Tianjin-Hebei and key areas across the country. In addition, the detection of ground or vertical profiles for atmospheric OH·, HO2·, NO3· radicals and reservoir molecules can now be obtained with domestic instruments in diverse environments. Moreover, laboratory smoke chamber simulations revealed heterogeneous processes involving reactions of O3 and NO2, which are typical oxidants in the surface/interface atmosphere, and the evolutionary and budgetary implications of atmospheric oxidants reacting under multispecies, multiphase and multi-interface conditions were obtained. Finally, based on the GRAPES-CUACE adjoint model improved by Chinese scholars, simulations of key substances affecting atmospheric oxidation and secondary organic and inorganic aerosol formation have been optimized. Normalized numerical simulations of AOIe and AOIp were performed, and regional coordination of AOC was adjusted. An optimized plan for controlling O3 and PM2.5 was analyzed by scenario simulation.  相似文献   
8.
针对大型场所疏散出口通行能力不均衡现象,以某大型体育场馆为对象,建立Pathfinder疏散模型,通过不断改变行人出口选择,得到行人疏散分区优化模型。结果表明:通过对比优化前后疏散时间、疏散过程及疏散出口利用差异,得到疏散时间优化效率10.55%,各出口疏散时间标准差优化效率为90.78%。分区优化能够均衡各出口疏散时间,提高疏散出口利用效率,有效缓解大型场所拥堵问题,为实现大型场所安全疏散提供理论参考。  相似文献   
9.
Environmental Science and Pollution Research - There is a delayed (lag 1 to 2 days) correlation between acute PM 2.5 (particulate matter <?2.5 μm in aerodynamic...  相似文献   
10.

Waterpipe (aka hookah) tobacco smokers are exposed to toxicants that can lead to oxidative DNA and RNA damage, a precursor to chronic disease formation. This study assessed toxicant exposure and biomarkers of DNA [8-oxo-7, 8-dihydro-2′-deoxyguanosine (8-oxodG)] and RNA [8-oxo-7,8-dihydroguanosine (8-oxoGuo)] oxidative damage during smoking of flavored and non-flavored waterpipe tobacco. Thirty waterpipe smokers completed two counterbalanced 2-h lab waterpipe smoking sessions (flavored vs. non-flavored waterpipe tobacco). Urinary concentrations of 8-oxodG and 8-oxoGuo and expired carbon monoxide (eCO) were measured before and after the smoking sessions. A significant increase in the urinary concentrations of 8-oxodG (from 2.12 ± 0.83 to 2.35 ± 0.91 ng/mg creatinine, p = 0.024) and 8-oxoGuo (from 2.96 ± 0.84 to 3.45 ± 0.76 ng/mg creatinine, p = 0.003) were observed after smoking the non-flavored and flavored waterpipe tobacco, respectively. Our results also showed that the mean ± SD of eCO increased significantly after smoking the flavored (from 1.3 ± 1.1 to 20.3 ± 23.6 ppm, p < 0.001) and non-flavored waterpipe tobacco (from 1.8 ± 1.2 to 24.5 ± 26.1 ppm, p < 0.001). There were no significant differences in the means of 8-oxodG (p = 0.576), 8-oxoGuo (p = 0.108), and eCO (p = 0.170) between the flavored and non-flavored tobacco sessions. Smoking non-flavored and flavored waterpipe tobacco leads to oxidative stress and toxicant exposure. Our findings add to the existing evidence about the adverse effects of waterpipe tobacco smoking (WTS) and the need for strong policies to inform and protect young people from the risks of WTS.

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