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51.
《International Journal of Hydrogen Energy》2020,45(41):20851-20858
In this paper, Ag-based g-C3N4 composites have been successfully fabricated through two deferent synthetic methods: (i) a facile and efficient precipitation-calcination strategy (denoted as D–CN–xAg, x represents the dosage of Ag2CO3, the same below), (ii) a calcination method (denoted as Z–CN–xAg). All Ag-based g-C3N4 composites exhibit the enhanced photocatalytic activities under visible-light irradiation. Moreover, the optimal dosage of Ag2CO3 in the D–CN–xAg composite is found to be 5%, the corresponding hydrogen production capacity is 153.33 μmol g−1 h−1, which is 4.6 times higher than that of Z–CN–5%Ag composite. This might be attributed to appropriate content of metallic Ag and more active sites exposed on the surface of D–CN–5%Ag composite. Meanwhile, combining with photoelectrochemical results, it could be inferred that LSPR effect and the intimate interfacial between metallic Ag and g-C3N4 in the system play also important role for the improvement of photocatalytic activity. These results demonstrate that the appropriate loading of metallic Ag originated from Ag2CO3 into g-C3N4 could accelerate the separation and transfer of photogenerated electron-hole pairs, leading to the improvement of photocatalytic activity for hydrogen production from water splitting. Finally, a possible photocatalytic mechanism is proposed. 相似文献
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介绍了珠江三角洲属于水质型缺水和资源缺水城市的情况,提出建设节水减污型城市、确保水资源可持续利用应采取的基本对策及关键技术。 相似文献
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猎德污水处理厂为适应《城镇污水处理厂污染物排放标准》(GB18918-2002)对磷排放指标的严格要求以及方便全厂的生产运行管理,对化学除磷设施进行了全面改造,新建了1套液态硫酸铝投加装置,重新设计了投加点,控制系统采用手动和PLC自动控制两种方式。改造后出水总磷可以稳定达到GB18918-2002的一级B标准,但污泥产量明显增加。 相似文献
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猎德污水处理厂UNITANK工艺的运行效果 总被引:2,自引:3,他引:2
广州市猎德污水处理厂二期工程采用UNITANK处理工艺,一年多的运行实践表明,UNITANK工艺在进水浓度较低的大型城市污水处理厂的应用是可行的,关键在于找到适合于实际生产的工艺控制参数和运行模式. 相似文献
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《Information & Management》1995,29(3):153-164
The large number of organizations developing executive information systems (EISs) highlights the importance of understanding why executives use these systems. This survey investigated how ease of use, the number of features, and support staff characteristics are related to EIS acceptance. Acceptance was measured by the percentage of the targeted users who incorporate the EIS into their daily routine. High usage was not associated with ease of use, a large number of features, or the staff being physically close to the users. However, rapid development time was positively correlated with acceptance. Higher numbers of available features were associated with larger support staffs and larger user groups. The number of users was positively correlated with both staff size and EIS age. Existing EISs place a stronger emphasis on reporting internal rather than external data. 相似文献
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《Acta Metallurgica Materialia》1991,39(8):1817-1822
Detailed microstructural observations reveal the formation of three types of slip features during creep of copper at intermediate temperatures between 0.46–0.72 Tm, where Tm is the absolute melting point. Single slip occurs at the higher temperatures and lower stresses with the slip lines being inhomogeneously distributed among the grains at the lower strains. Complex wavy slip features are observed at the higher temperatures, higher stresses and with increasing strains, thereby suggesting that cross-slip mechanisms may be important under these conditions. The absence of these slip patterns at the lower temperatures and higher stresses, when mainly multiple slip morphologies are observed, suggests that cross-slip mechanisms are likely to control the creep of polycrystalline copper only in a limited range of stresses and temperatures. 相似文献
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