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511.
Designing effective control policy requires accurate quantification of the relationship between the ambient concentrations of O3and PM2.5and the emissions of their precursors.However,the challenge is that precursor reduction does not necessarily lead to decreases in the concentrations of O3and PM2.5,which are formed by multiple precursors under complex physical and chemical processes;this calls for the development of advanced model technologies to prov... 相似文献
512.
Hancheng Dai Xinyuan Liu Chaoyi Guo Yazhen Wu Chen Huang Keding Lu Yuanhang Zhang Lei Duan Miaomiao Cheng Fahe Chai Fengqiao Mei 《环境科学学报(英文版)》2023,123(1):140-155
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
513.
Miaomiao Cheng Linglu Qu Fahe Chai Shijie Liu Jingchun Duan Fan Meng 《环境科学学报(英文版)》2023,123(1):500-509
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
514.
In recent years, an increasing amount of interest has been dedicated to the synthesis and application of ZIF-67-based materials due to their exceptionally high surface area, tunable porosity, and excellent thermal and chemical stabilities. This review summarizes the latest strategies of synthesizing ZIF-67-based materials by exploring the prominent examples. Then, the recent progress in the applications of ZIF-67-based materials in heterogeneous catalysis, including catalysis of the redox reactions, addition reactions, esterification reactions, Knoevenagel con-densations, and hydrogenation–dehydrogenation reactions, has been elaborately discussed. Finally, we end this work by shedding some light on the large-scale industrial production of ZIF-67-based materials and their applications in the future. 相似文献
515.
516.
Duan Qingquan Zhang Hong Yan Feng Deng Changyi 《Journal of Loss Prevention in the Process Industries》2009,22(6):897-900
To evaluate the future application of X80 steel pipe in high-pressure oil and gas pipelines in China, hydrostatic burst tests were performed. The deformation and yield strength of longitudinal submerged arc-welding steel pipe Ф1016 × 18.4 mm under five applied pressure levels were measured. When the hoop stress is lower than 1.1SMYS, the pipe normally deforms elastically and uniformly with the maximum strain less than 0.3%. The slope offsets of the pressure–volume plot of pipe were discussed. 相似文献
517.
Bruno Takahashi Guy Edwards J. Timmons Roberts Ran Duan 《Environmental Communication: A Journal of Nature and Culture》2015,9(2):228-247
The engagement of environmental non-governmental groups in collaborative communication efforts and decision-making about climate change remains a significant challenge. In Latin America, the website Intercambio Climático was set up to attempt to play a breakthrough role in the region's discussion of climate change. This case study focuses on the development, accomplishments, and challenges of this unique online communication initiative among non-governmental organizations working in climate change issues in Latin America with a US-based partner, as a vehicle to achieve their goals. We used secondary data and in-depth interviews to examine this platform's role in disseminating information and influencing decision-making. The results suggest that generally the participants perceive the website positively, but there are also problematic aspects of the collaboration that are not fully recognized by the members, which prevents a more functional and effective communication strategy. 相似文献
518.
利用自组装工艺流程对驯化后的小球藻进行CO2捕集实验和相应培养工艺条件的初步研究。由于抑制小球藻生长的主要影响因素是高浓度的CO2气体和由于CO2溶解于培养液中导致的溶液p H值的降低,为了能够优化培养工艺,在实验中设计了2种培养体系分别考察这些影响因素对藻生长的影响。实验发现高密度藻细胞培养体系对高浓度CO2和低p H环境的耐受能力要大于低密度细胞培养体系,并且生长速度和固碳能力也相应提高。这是由于高密度细胞培养体系有更好的p H缓冲能力和吸收CO2的能力。这样的培养特性为进一步优化微藻培养体系,分段培养小球藻进行大规模CO2的捕集和利用提供了有力的实验数据。 相似文献
519.
利用偶发分枝杆菌(Mycobacterium fortuitum)CICC 10279发酵断甾醇侧链进行定向菌株筛选;对选出的具有较高甾醇降解活性的菌株,借助TLC法开展多批次生物降解实验过程研究;并重点对积累9α-羟基雄烯二酮(9α-OH-AD)化合物的菌株稳定性及转化过程进行考察;在此基础上利用选出的22号菌株分别进行底物为胆固醇和植物甾醇的半微量制备实验.结果显示,分离的样品具有高纯度,HPLC分析为95.7%;TLC、HPLC、MS、1H N M R、13C N M R、i.r.等光谱数据分析结构确证其为9α-OH-A D;半微量制备实验以胆固醇或植物甾醇为底物,9α-OH-A D重量收得率分别可达34.0%和30.8%.本研究可能为高效含卤(氟,氯)皮质激素药物工业生产提供了一种很有用处的中间体. 相似文献
520.
消油剂与120#燃料油对马粪海胆(Hemicentrotus pul-cherrimus)抗氧化酶活性的影响 总被引:2,自引:0,他引:2
在溢油事故应急处置中,消油剂的使用备受争议。为探究消油剂和溢油对海洋底栖模式生物海胆(Hemicentrotus pulcherrimus)复合毒性效应,通过WAFs(Water-accommodated fractions)和CEWAFs(Chemically enhanced water-accommodated fractions)的96 h暴露实验,测定海胆肠和性腺中过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、谷胱甘肽硫转移酶(GST)、谷胱甘肽过氧化物酶(GPx)活性的变化。实验结果表明:随油水配比浓度的增加,4种酶活性呈现先升高后降低趋势,且酶活性峰值均极显著高于海水对照组水平(P0.01)。肠中4种酶活性最大诱导倍数均高于性腺。相同暴露浓度下,CEWAFs组4种酶活性诱导程度均高于WAFs组。消油剂对照组和海水对照组间4种酶活性则无显著性差异(P0.05)。 相似文献