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891.
892.
研究了以美国为首的发达国家城镇化的发展历程,称为“A模式”,主要特征为城市低密度蔓延、全民机动化、资源大量消耗、一次性产品泛滥、过度消费等,总结经验教训,对比中国特色城镇化的发展历程,称为“ B模式”,主要特点是起步晚、水平较低、速度快,从资源与环境的角度分析了中国城镇化发展状况以及面临的形势,指出中国继续以“B模式”的城镇化发展将不可持续,不再适应中国建设“新型城镇化”的发展目标和日益提高的环保要求,探索实现中国“新型城镇化”的发展目标的“C模式”,即是坚持以节约优先、保护优先、自然恢复为原则,走以新型工业化和农业现代化推动下的新型城镇化道路。 相似文献
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896.
Jiao He Guoli Zi Zhiying Yan Yongli Li Jiao Xie Deliang Duan Yongjuan Chen Jiaqiang Wang 《环境科学学报(英文版)》2014,26(5):1195-1202
Cyanobacteria, which occurred in eutrophic water harvest solar light to carry out photosynthesis with high efficiency. In this work, cyanobacteria (Microcystis sp.) were used as biotemplate to synthesize titania structure. The synthesized titania sample had similar morphology to that of the original template in spite of the fragile unicellular structures and extremely high water content of cyanobacterial cells. Incorporation of biogenic C, as well as the morphology inherited from biotemplate improved visible- light absorbance of the titania structure. The sample exhibited higher visible-light photocatalytic activity than commercial titania photocatalyst Degussa P25 for Rhodamine B (RhB) degradation. Compared with those C-doped titania photocatalysts prepared by other methods, cyanobacteria templated titania photocatalyst offer some potential for competitive advantages. The reported strategy opened up a new use for the cyanobacteria. It could also be used for titania in applications such as treatment of polluted water, dye-sensitized solar cells, or other regions. 相似文献
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通过对当前应急救援队伍的装备配置和维护保养情况进行调查,结合基层队伍的专项训练情况,分析现阶段应急救援队伍应急保障中存在的薄弱点,就如何提高应急救援队伍的救援能力提出建议。 相似文献
899.
Comparison of catalytic activity of two platinised TiO2 films towards the oxidation of organic pollutants 总被引:2,自引:0,他引:2
Two types of platinised TiO2 films, i.e., Pt-TiO2/ITO and Pt(TiO2)/ITO, were prepared by a procedure of dip-coating and subsequent photo-deposition, and photo-deposition and subsequent dip-coating, respectively. They were well characterized by DRS, XRD spectra, SEM microscopy and photoelectrochemical measurement. Their photocatalytic, dark catalytic and photoelectrocatalytic activities were investigated using formic acid as a model organic pollutants. Compared with pure TiO2/ITO film, the photocatalytic activity of the platinised TiO2 films were apparently improved. However, the improvement was considerably dependent on the preparation method of these films. Pt-TiO2/ITO not only possessed higher photocatalytic activity but also showed a dark catalytic activity towards HCOOH degradation. As a sequence, it was first emphasized that the dark catalytic effect of Pt-TiO2/ITO was partly responsible for degradation of formic acid in the photocatalytic oxidation process. Although the Pt(TiO2)/ITO film does not exhibit the dark catalytic activity, its photocatalytic degradation efficiencies towards HCOOH are higher than that of Pt-TiO2/ITO film. Therefore, in view of enhanced photocatalytic activity, the Pt(TiO2)/ITO was more favored than Pt-TiO2/ITO film. 相似文献
900.
Trace level perchlorate analysis in water initiated a new development in the Ion Chromatography (IC) technology. Maintenance of a low detection limit may be highly affected by the operating conditions of the IC system. In this paper the homoscedasticity of the IC system within the calibration concentration range, the effect of the system drift on the calibration curve and the effect of the self regeneration suppressor (SRS) current on the detection limit were investigated. The experimental results were evaluated by statistical methods such as the Cochran test and the lack of fit test. The detection limits were obtained by two ways. One through method detection limit (MDL) and the other through detection limit from the calibration curve (DTC). The Cochran test results revealed the homoscedasticity of the IC system. The effect of system drift on the calibration curve was noticed by the lack of fit test. MDL yielded a lower but less reliable detection limit than DTC. An acceptable detection limit can be achieved under the lower SRS current (100 mA). 相似文献