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551.

As the digital economy develops rapidly and the network information technology advances, new development models represented by the network economy have emerged, which have a crucial impact on green economic growth. However, the relevant previous studies lacked the role of analyzing the direct and indirect effects of internet development on green economic growth at the prefecture-level city level. For this purpose, this paper aims to examine the intrinsic mechanism of the impact of internet development on green economic growth and provide empirical support for cities and regions in China to increase internet construction. Furthermore, the mixed model (EBM), which includes both radial and non-radial distance functions, is applied to calculate the green economic growth index. Fixed effect model and mediation effect model are also employed to test influence mechanisms of the internet development on green economic growth using panel data of 269 prefecture-level cities in China from 2004 to 2019. The statistical results reveal that internet development has contributed significantly to green economic growth. When the internet development level increases by 1 unit, the green economic growth level increases by an average of 5.0372 units. However, regional heterogeneity is evident between internet development and green economic growth, that is, the promoting effect of internet development on green economic growth is gradually enhanced from the eastern region to the western region. We also find that internet development guides industrial structure upgrading improves environmental quality and accelerates enterprise innovation, which indirectly contributes to green economic growth. And internet development mainly achieves green economic growth through enterprise innovation. Based on the above findings, we concluded that policymakers should not only strengthen the guiding role of social actors to promote the stable development of the internet industry, but also foster the construction of the three models of “internet+industry integration,” “internet+environmental governance,” and “internet+enterprise innovation” to promote green economic growth.

  相似文献   
552.
Environmental Science and Pollution Research - Air pollution is one of the biggest environmental health problems in the world; accumulative studies have shown that air pollution was closely related...  相似文献   
553.
Feng  Yanlu  Liu  Tong  Xu  Siyi  Ren  Yiyi  Ge  Yiling  Yin  Lihong  Pu  Yuepu  Liang  Geyu 《Environmental science and pollution research international》2022,29(46):69153-69175
Environmental Science and Pollution Research - The health risks caused by environmental pollution have long been of substantial concern. With the development of epigenetics, a large number of...  相似文献   
554.
Environmental Science and Pollution Research - Marine corrosion is a kind of material failure phenomenon caused by the interaction between metal structure and marine environment. As an efficient...  相似文献   
555.
田婧 《环境工程》2008,26(5):31-34
通过对建筑施工企业管理人员及施工场地周围居民的环境保护态度进行调查研究,结果表明:在污染治理方面,建筑垃圾主要以当场焚烧和运往指定地点填埋为主。施工噪声主要是禁止夜间施工和修建噪声防护墙为主。引起目前建筑施工污染环境的主要原因为环境监察力度不够,环保投入少,管理不科学等三个方面。从健全法律法规,增大环保宣传力度,加强对施工单位的管理,改进施工工艺等提出相应的解决方法,以解决目前建筑施工企业在环境保护方面存在的问题,减少污染,增强人们的环境保护意识。  相似文献   
556.
Spatially periodic vegetation patterns, forming gaps, bands, labyrinths, or spots, are characteristic of arid and semiarid landscapes. Self-organization models can explain this variety of structures within a unified conceptual framework. All these models are based on the interplay of positive and negative effects of plants on soil water, but they can be divided according to whether they assume the interactions to be mediated by water redistribution through runoff/diffusion or by plants' organs. We carried out a multi-proxy approach of the processes operating in a gapped pattern in southwest Niger dominated by a shrub species. Soil moisture within the root layer was monitored in time and space over one month of the rainy season. Soil water recharge displayed no spatial variation with respect to vegetation cover, but the stock half-life under cover was twice that of bare areas. A kernel of facilitation by the aboveground parts of shrubs was parameterized, and soil water half-life was significantly correlated to the cumulated facilitative effects of shrubs. The kernel range was found to be smaller than the canopy radius (81%). This effect of plants on soil water dynamics, probably through a reduction of evaporation by shading, is shown to be a better explanatory variable than potentially relevant soil and topography parameters. The root systems of five individuals of Combretum micranthum G. Don were excavated. Root density data were used as a proxy to parameterize a kernel function of interplant competition. The range of this kernel was larger than the canopy radius (125%). The facilitation-to-competition range ratio, reflecting the above-to-belowground ratio of plant lateral extent, was smaller than 1 (0.64), a result supporting models assuming that patterning may emerge from an adaptation of plant morphology to aridity and shallow soils by means of an extended lateral root system. Moreover, observed soil water gradients had directions opposite to those assumed by alternative mathematical models based on underground water diffusion. This study contributes to the growing awareness that combined facilitative and competitive plant interactions can induce landscape-scale patterns and shape the two-way feedback loops between environment and vegetation.  相似文献   
557.
通过对恒液位推流式改良SBR工艺处理生活污水工程应用的研究,结果表明:恒液位推流式改良SBR工艺在降低工程成本和减少设备量的同时能较好的去除污水中的污染物,具有良好的脱氮除磷效果,COD去除率可达85%~93%;TP的去除率可达84%;TN的去除率可达82%。  相似文献   
558.
Biological hydrogen production by dark fermentation is an important part of biological hydrogen production technologies. China is a typical developing country that heavily relies on fossil fuels; thus, new, clean, and sustainable energy development turns quite urgent. It is delightful that Chinese government has already drawn up several H2 development policies since 1990s and provided financial aid to launch some H2 development projects. In this paper, the research status on dark fermentative hydrogen production in China was summarized and analyzed. Subsequently, several new findings and achievements, with some of which transformed into scale-up tests, were highlighted. Moreover, some prospecting coupling processes with dark fermentation of hydrogen production were also proposed to attract more research interests in the future.  相似文献   
559.
对近年来关于炼油碱渣的各种处理方法及其应用作了介绍,从投资费用、运行费用、运行管理和安全风险等诸方面进行了对比,并指出生物处理方法是今后炼油碱渣处理的一种趋势.  相似文献   
560.
环境水中污染物亚硝酸根的现场快速测定研究   总被引:13,自引:1,他引:12  
通过研制一种环境保护试纸从而能简便快速地现场半定量测定环境水中污染物亚硝酸根,便于野外水环境普查,应用它可使测定时间由标准法的3h左右短到5min,使分析成本大为降低。  相似文献   
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