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1.
产业转型是资源枯竭型城市面临的重要发展问题,探究资源枯竭型城市产业转型及其经济韧性的演化机制,对实现城市高质量发展具有重要意义。从演化经济韧性视角出发,以湖北省大冶市为例,构建资源枯竭型城市经济韧性评价指标体系,采取熵值法和PLS偏最小二乘法,定量揭示2000—2019年湖北省大冶市产业转型过程中经济韧性的演化特征及驱动机制。结果显示:(1)研究区经济韧性经历了衰退适应、抵御恢复、响应提升的演化阶段,分别对应其经济衰退转变期(2000—2009年)、发展恢复期(2010—2014年)、高效提升期(2015—2019年),经济韧性水平呈现出“缓慢→快速”的上升态势。(2)2000—2019年研究区经济韧性演化的驱动因子由产业结构转变和创新水平提升转向多要素共同推动,其中居民收入、市场规模、政府调控能力、产业技术水平等因子是推进研究区经济韧性演进的关键因素。(3)产业多元化转型是研究区经济韧性提升的直接动力,以产业相关多样化为传导路径,在多要素驱动下研究区向更高层次的城市生命阶段演进。当压力要素消解、城市状态调整、响应方式优化时,经济韧性将通过激活产业要素、均衡化拓展驱动力来推动产业的“路...  相似文献   
2.
In the United States, thermal power plant electrical generators (EGs) are large water diverters and consumptive users who need water for cooling. Retrofitting existing cooling systems to dry cooling and building new facilities with dry cooling can save water and reduce EG's vulnerability to drought. However, this can be an expensive source of water. We estimate that the cost of water saved by retrofitting cooling in existing EGs ranges from $0.04/m3 to $18/m3 depending on facility characteristics. Also water savings from building new EGs with dry cooling ranges in cost per unit water from $1.29/m3 to $2.24/m3. We compare costs with that for water development projects identified in the Texas State Water Plan. We find the water cost from converting to dry cooling is lower than many of the water development possibilities. We then estimate the impact of climate change on the cost of water saved, finding climate change can increase EG water use by up to 9.3% and lower the costs of water saved. Generally, it appears that water planners might consider cooling alterations as a cost competitive water development alternative whose cost would be further decreased by climate change.  相似文献   
3.
Environmental Science and Pollution Research - Urbanization has led to the rapid and large-scale changes in land use and land cover and has affected the spatial distribution of land surface...  相似文献   
4.
Environmental Science and Pollution Research - Metallic glasses (MGs) with unique disordered atomic stacking structures exhibit excellent catalytic performance in wastewater treatment. The...  相似文献   
5.
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   
6.

Characterization of the typical petroleum pollutants, polycyclic aromatic hydrocarbons (PAHs) and n-alkanes, and indigenous microbial community structure and function in historically contaminated soil at petrol stations is critical. Five soil samples were collected from a petrol station in Beijing, China. The concentrations of 16 PAHs and 31 n-alkanes were measured by gas chromatography-mass spectrometry. The total concentrations of PAHs and n-alkanes ranged from 973 ± 55 to 2667 ± 183 μg/kg and 6.40 ± 0.38 to 8.65 ± 0.59 mg/kg (dry weight), respectively, which increased with depth. According to the observed molecular indices, PAHs and n-alkanes originated mostly from petroleum-related sources. The levels of ΣPAHs and the total toxic benzo[a]pyrene equivalent (ranging from 6.41 to 72.54 μg/kg) might exert adverse biological effects. Shotgun metagenomic sequencing was employed to investigate the indigenous microbial community structure and function. The results revealed that Proteobacteria and Actinobacteria were the most abundant phyla, and Nocardioides and Microbacterium were the important genera. Based on COG and KEGG annotations, the highly abundant functional classes were identified, and these functions were involved in allowing microorganisms to adapt to the pressure from contaminants. Five petroleum hydrocarbon degradation-related genes were annotated, revealing the distribution of degrading microorganisms. This work facilitates the understanding of the composition, source, and potential ecological impacts of residual PAHs and n-alkanes in historically contaminated soil.

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7.

The Yellow River Delta is the largest and youngest estuarine and coastal wetland in China and is experiencing the most active interactions of seawater and freshwater in the world. Bacteria played multifaceted influence on soil biogeochemical processes, and it was necessary to investigate the intermodulation between the soil factors and bacterial communities. Soil samples were collected at sites with different salinity degree, vegetations, and interference. The sequences of bacilli were tested using 16S rRNA sequencing method and operational taxonomic units were classified with 97% similarity. The soil was highly salinized and oligotrophic, and the wetland was nitrogen-restricted. Redundancy analysis suggested that factors related with seawater erosion were principal to drive the changes of soil bacterial communities and then the nutrient level and human disturbance. A broader implication was that, in the early succession stages of the coastal ecosystem, seawater erosion was the key driver of the variations of marine oligotrophic bacterial communities, while the increasing nutrient availability may enhance in the abundance of the riverine copiotrophs in the late stages. This study provided new insights on the characteristics of soil bacterial communities in estuarine and coastal wetlands.

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8.
Environmental Science and Pollution Research - The rapid economic development in China places a large demand for energy, and as a result, thermal power plants in China are producing an enormous...  相似文献   
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10.
Because of the recent growth in ground-level ozone and increased emission of volatile organic compounds (VOCs), VOC emission control has become a major concern in China. In response, emission caps to control VOC have been stipulated in recent policies, but few of them were constrained by the co-control target of PM2.5 and ozone, and discussed the factor that influence the emission cap formulation. Herein, we proposed a framework for quantification of VOC emission caps constrained by targets for PM2.5 and ozone via a new response surface modeling (RSM) technique, achieving 50% computational cost savings of the quantification. In the Pearl River Delta (PRD) region, the VOC emission caps constrained by air quality targets varied greatly with the NOx emission reduction level. If control measures in the surrounding areas of the PRD region were not considered, there could be two feasible strategies for VOC emission caps to meet air quality targets (160 µg/m3 for the maximum 8-hr-average 90th-percentile (MDA8-90%) ozone and 25 µg/m3 for the annual average of PM2.5): a moderate VOC emission cap with <20% NOx emission reductions or a notable VOC emission cap with >60% NOx emission reductions. If the ozone concentration target were reduced to 155 µg/m3, deep NOx emission reductions is the only feasible ozone control measure in PRD. Optimization of seasonal VOC emission caps based on the Monte Carlo simulation could allow us to gain higher ozone benefits or greater VOC emission reductions. If VOC emissions were further reduced in autumn, MDA8-90% ozone could be lowered by 0.3-1.5 µg/m3, equaling the ozone benefits of 10% VOC emission reduction measures. The method for VOC emission cap quantification and optimization proposed in this study could provide scientific guidance for coordinated control of regional PM2.5 and O3 pollution in China.  相似文献   
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