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1.
数字产业化与产业数字化是数字经济的"双重向度",其耦合协调程度对于优化数字经济发展结构具有重要意义.揭示与阐述数字产业化与产业数字化的耦合机理,建立评价两者耦合协调度的理论模型,设计评价两者耦合协调状况及趋势的指标体系,运用长江经济带11省市2013~2018年的面板数据,实证分析长江经济带数字产业化与产业数字化的耦合协调度.结果表明:长江经济带数字产业化水平和产业数字化水平稳步提升,总体耦合协调度区域差异明显,存在数字产业化滞后产业数字化的趋势.从加快推进新型数字产业发展、以"新基建"助力传统产业数字化转型、为区域间数字经济协调发展和区域内数字化转型构建更好制度体系、加强数字人才培养和激励等方面,提出促进我国数字产业化与产业数字化融合发展的政策建议.  相似文献   
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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   
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纳米铁氧化物吸附处理重金属废水的研究进展   总被引:2,自引:0,他引:2       下载免费PDF全文
概述了用于吸附重金属的主要纳米铁氧化物的种类及其吸附效果,介绍了常见的纳米铁氧化物制备方法及改性方法,讨论了影响纳米铁氧化物吸附重金属的主要因素,并对纳米铁氧化物在水环境保护领域中的研究方向提出了展望:如发展绿色、高效的纳米铁氧化物制备工艺,探讨纳米铁氧化物结构调控和表面功能化对其吸附性能的影响等。  相似文献   
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Environmental Science and Pollution Research - China is the most populous country in the world, and the pollution caused by the excessive population should not be underestimated. In recent years,...  相似文献   
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This study investigated the levels, sources and ecological risks of 16 polycyclic aromatic hydrocarbons (PAHs) in two sediment cores that were collected along the Huaxi Reservoir. The spatial distributions and residue levels of the 16 priority PAHs in the sediments from the Huaxi Reservoir were analyzed for their potential ecological risk, source apportionment and contribution to the total PAH residue. The concentration level of the total PAHs (TPAHs) was in the range 1805 ng·g?1 to 20023 ng·g?1 based on dry weight, and the content of PAHs in the Huaxi Reservoir exhibited a gradual upward trend. The PAH congener ratios fluoranthene/(fluoranthene + pyrene) and indeno[1, 2, 3-cd]pyrene/(indeno[1, 2, 3-cd]pyrene + benzo[g, h, i]perylene) were used to identify the source. The main source of the low molecular weight PAHs was wood and coal combustion, whereas the high molecular weight PAHs were primarily from petroleum combustion sources. The results of an ecological risk assessment demonstrated that ACE poses a potential ecological risk, while FLU, NAP, ANT, BaP, DBA, PHEN and PYR can have serious ecological risks.  相似文献   
8.
Land degradation is a global problem that seriously threatens human society. However, in China and elsewhere, ecological restoration still largely relies on a traditional approach that focuses only on ecological factors and ignores socioeconomic factors. To improve the effectiveness of ecological restoration and maximize its economic and ecological benefits, a more efficient approach is needed that provides support for policy development and land management and thereby promotes environmental conservation. We devised a framework for assessing the value of ecosystem services that remain after subtracting costs, such as the opportunity costs, costs of forest protection, and costs for the people who are affected by the program; that is, the net value of ecosystem services (NVES). To understand the difference between the value of a resource and the net value of the ecosystem service it provides, we used data on VES, timber sales, and afforestation costs from China's massive national afforestation programs to calculate the net value of forest ecosystem services in China. Accounting for the abovementioned costs revealed an NVES of ¥6.1 × 1012 for forests in 2014, which was 35.9% less than the value calculated without accounting for costs. As a result, the NVES associated with afforestation was 55.9% less than the NVES of natural forests. In some regions, NVES was negative because of the huge costs of human-made plantations, high evapotranspiration rates (thus, high water opportunity costs), and low forest survival rates. To maximize the ecological benefits of conservation, it is necessary to account for as many costs as possible so that management decisions can be based on NVES, thereby helping managers choose projects that maximize both economic and ecological benefits.  相似文献   
9.
Fu  Li  Chen  Yi  Yang  Xinyi  Yang  Zuyao  Liu  Sha  Pei  Lei  Feng  Baixiang  Cao  Ganxiang  Liu  Xin  Lin  Hualiang  Li  Xing  Ye  Yufeng  Zhang  Bo  Sun  Jiufeng  Xu  Xiaojun  Liu  Tao  Ma  Wenjun 《Environmental science and pollution research international》2019,26(20):20137-20147
Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air...  相似文献   
10.
The quantitative relationship between the median effective concentration (EC50) of organic chemicals to Daphnia magna and the number of molecular fragments was investigated based on experimental EC50 values for 217 chemicals derived from the literature. A fragment constant model was developed based on a multivariate linear regression between the number of fragments and the logarithmically transformed reciprocal values of EC50. Functional correction factors were introduced into the model. The model was verified using an independent set of randomly selected data. The mean residual of the final model was 0.4 log-units. The robustness of the model was discussed based on the results of three jackknife tests.  相似文献   
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