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251.
Preface     
Anthropogenic emissions impact significantly the atmospheric environment which human being relies on, e.g., global warming, stratospheric ozone depletion, photochemical smog, acid rain, haze and so on. Although clean air actions have been legislated by many nations to mitigate pollutants' emission with the aim of protecting the atmospheric environment, serious air pollution events are frequently observed in different regions, especially in developing countries. To best evaluate the effect of various control measures as well as the influence of various pollutants on the atmospheric environment, the levels, sources and sinks of the pollutants are needed to be comprehensively investigated. Since atmospheric environment involves multidisciplinary approach, scientists with different disciplines together can provide profound understandings about the atmospheric environmental problems. Sino-French Workshop on Atmospheric Environment is just one of such platforms to join scientists together for collaboration, exchange of experience and ideas.  相似文献   
252.
Air pollutant emissions represent a critical challenge in the green development of the non-ferrous metallurgy industry.This work studied the emission characteristics,formation mechanisms,phase transformation and separation of typical air pollutants,such as heavy metal particles,mercury,sulfur oxides and fluoride,during non-ferrous smelting.A series of purification technologies,including optimization of the furnace throat and hightemperature discharge,were developed to collaboratively control and...  相似文献   
253.
China has put great efforts into air pollution control over the past years and recently committed to its most ambitious climate target. Cost and benefit analysis has been widely used to evaluate the control policies in terms of past performance, future reduction potential,and direct and indirect impacts. To understand the cost and benefit analysis for air pollution control in China, we conducted a bibliometric review of more than 100 studies published over the past two decades, including the cur...  相似文献   
254.
Ambient air quality standards are the core strategic goal of ambient air quality management. Countries worldwide have given importance to research on the development of ambient air quality standards. To understand the history of the development of China's ambient air quality standards, this study analyzed the background associated with all previous formulations and revisions of the standards, classification of functional areas, standard grading, pollutants, and evolution of the standard limits over the past 40 years. The results show that since the initial release of the “Ambient Air Quality Standard” by China in 1982, it has been supplemented once, revised twice, and modified twice. The first ambient air quality standard specified the standard limits of six pollutants commonly found in ambient air. With the development of ambient air quality management, the number of pollutants has increased to ten. Since the release of the “Ambient Air Quality Standards” in 2012, the ambient air quality in China has significantly improved. However, the proportion of cities meeting these standards is still low. At present, China is suitably positioned to make the standards associated with 24 hr SO2 concentrations more stringent such that it meets the values defined in the World Health Organization (WHO) interim target-2 and the WHO air quality guideline (AQG). We further suggested that the SO2 standard should be revised promptly. Simultaneously, regions with a relatively high proportion of cities meeting the standard are encouraged to introduce more stringent interim target limits in due course to manage the local ambient air quality.  相似文献   
255.
Air quality monitoring is effective for timely understanding of the current air quality status of a region or city. Currently, the huge volume of environmental monitoring data, which has reasonable real-time performance, provides strong support for in-depth analysis of air pollution characteristics and causes. However, in the era of big data, to meet current demands for fine management of the atmospheric environment, it is important to explore the characteristics and causes of air pollution from multiple aspects for comprehensive and scientific evaluation of air quality. This study reviewed and summarized air quality evaluation methods on the basis of environmental monitoring data statistics during the 13th Five-Year Plan period, and evaluated the level of air pollution in the Beijing–Tianjin–Hebei region and its surrounding areas (i.e., the “2+26” region) during the period of the three-year action plan to fight air pollution. We suggest that air quality should be comprehensively, deeply, and scientifically evaluated from the aspects of air pollution characteristics, causes, and influences of meteorological conditions and anthropogenic emissions. It is also suggested that a three-year moving average be introduced as one of the evaluation indexes of long-term change of pollutants. Additionally, both temporal and spatial differences should be considered when removing confounding meteorological factors.  相似文献   
256.
以降雨侵蚀力、地形起伏度、土壤质地、植被覆盖度等自然因素及土壤侵蚀敏感性综合指数作为评价指标,利用GIS与RS技术,对隆昌市土壤侵蚀敏感性进行定量分析,并研究其分布特征,为地区水土保持工作提供科学依据.研究表明:隆昌市土壤侵蚀敏感性整体以轻度敏感为主,降雨及土壤质地对土壤侵蚀影响较大,桂花井镇、金鹅镇、李市镇、圣灯镇、石燕桥镇、渔箭镇土壤侵蚀相对较为敏感,是今后水土保持的重点区域.  相似文献   
257.
Epidemiological evidences show that prenatal caffeine exposure (PCE) could induce intrauterine growth retardation (IUGR). The IUGR offspring also present glucose intolerance and type 2 diabetes mellitus after maturity. We have previously demonstrated that PCE induced IUGR and increased susceptibility to adult metabolic syndrome in rats. This study aimed to further investigate the effects of PCE on glucose homeostasis in adult offspring rats. Pregnant rats were administered caffeine (120 mg/kg/day, intragastrically) from gestational days 11 to 20. PCE offspring presented partial catch-up growth pattern after birth, characterizing by the increased body weight gain rates. Meanwhile, PCE had no significant influences on the basal blood glucose and insulin phenotypes of adult offspring but increased the glucose tolerance, glucose-stimulated insulin section and β cell sensitivity to glucose in female progeny. The insulin sensitivity of both male and female PCE offspring were enhanced accompanied with reduced β cell fraction and mass. Western blotting results revealed that significant augmentation in protein expression of hepatic insulin signaling elements of PCE females, including insulin receptor (INSR), insulin receptor substrate 1 (IRS-1) and the phosphorylation of serine–threonine protein kinase (Akt), was also potentiated. In conclusion, we demonstrated that PCE reduced the pancreatic β mass but increased the glucose tolerance in adult offspring rats, especially for females. The adaptive compensatory enhancement of β cell responsiveness to glucose and elevated insulin sensitivity mainly mediated by upregulated hepatic insulin signaling might coordinately contribute to the increased glucose tolerance.  相似文献   
258.
周贵忠  许硕  姚倩  银钗 《环境科学》2017,38(7):2972-2977
通过逐渐提高SBR反应器中活性污泥的盐度,探索不同盐度下活性污泥的活性、性质及其微生物群落变化,并研究结晶紫废水以及纳米四氧化三铁对微生物群落的影响.结果表明,随着盐度的增加,活性污泥的COD、氨氮去除率以及污泥体积指数SVI值均降低,在质量分数2%的盐度下,COD、NH_4~+-N的去除率为80%和75%,SVI值不足35 mL·g~(-1);随着盐度的增加微生物的多样性逐渐减少,系统中革兰氏阴性菌优势菌种的位置逐渐被真菌和放线菌取代,而革兰氏阳性菌依然为优势菌;加入结晶紫染料的活性污泥与盐度为2%的活性污泥样品相比发现:红细菌属、丽水菌属含量有所增加,产黄杆菌、农杆菌属含量减小.加入MNPs的结晶紫-活性污泥与不加MNPs的结晶紫活性污泥对比:酸胞菌属、产黄杆菌含量增加,红细菌属、农杆菌属含量减小.  相似文献   
259.
260.
The SO2 emission sources of the Chengdu-Chongqing economic zone were divided into 556 emissions units according to four different categories, which are city, industry, point sources, and area sources. The CALPUFF model was used to calculate the contribution of each unit, and consequently obtain an influence-transferring matrix. To ensure that the SO2 concentrations of 46 cities and counties in the Chengdu-Chongqing economic zone meet air quality standards, an emission optimization model was developed to calculate optimal emissions of each emission unit under different development scenarios. The result showed the optimal emissions of SO2 by different provinces and industries. To achieve the target of restricting and optimizing development, corresponding planning programs were developed for every district.  相似文献   
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