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861.
Lei Li Jian Xu Changsheng Guo Yuan Zhang 《Frontiers of Environmental Science & Engineering》2013,7(3):382-387
Hexahedron-like BiPO4 microcrystals were sucessfully synthesized via a template-free hydrothermal method. The resulting samples were characterized by Xray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and UV-vis spectroscopy. The BiPO4 samples were of pure monoclinic phase, and the initial amount of PO3–4 during synthesis did not show obvious effect on the phase properties of the materials. The hexahedron-like BiPO4 microcrystal had explicitly cut edges, and its thickness was about 1 μm. The photocatalytic performance of the BiPO4 catalysts was evaluated by photodegradation of RhB under UV light irradiation with commerial Degussa P25 TiO2 as reference. Compared with P25, the BiPO4 catalysts displayed higher photocatalytic activity, with 98.7% of RhB degraded during 60-min experiment. Cost evaluation analysis was adopted to describe the energy consumption of the degradation process, and the results suggested the potential application of this material in the field of dye-contaminated wastewater treatment or environmental matrices remediation. 相似文献
862.
Evaluation of sustainability is the core of research on sustainable land use. To a certain extent, traditional social, economic and ecological evaluation for sustainable land use can be regarded as an appraisal on the temporal scale without evaluation of spatial patterns. Landscape ecology can help to realize spatial evaluation for sustainable land use. In this paper, we construct landscape ecological indicators for evaluating sustainable coastal land use from the aspects of landscape productivity, threats and stability, to realize a synthetic temporal-spatial evaluation. These cover the five pillars of sustainable land use, i.e. productivity, security, protection, viability and acceptability. The results of applying landscape ecological evaluation to a case study in Wudi County in China show that land use sustainability is somewhat low and there are great regional differences between its 11 villages. We classified the 11 villages into 5 grades: strong sustainable land use, sustainable land use, weak sustainable land use, weak unsustainable land use, and strong unsustainable land use. Each grade has different land use characteristics and differs in the counter-measures required. But the core countermeasures in all the grades are to improve landscape productivity, to reduce human threats and to optimize landscape patterns. 相似文献
863.
Hui Wang Fa Yuan Wang Zhi Qiang Wei Hong Ying Hu 《Environmental monitoring and assessment》2011,176(1-4):157-167
A total of 11 sediment samples were collected from the sites along Haihe River?CBohai Bay, with site 1 at the beginning of Haihe River and site 11 in Bohai Bay, about 150 km away from site 1. Quinone profiles were used for the analysis of microbial community as influenced by pollutants in water and sediments, such as heavy metals, and other environmental factors. Nineteen species of quinones were found at site 1 while only six species at sites 10 and 11. Both the diversity of quinone species (DQ) and the number of quinones were higher in the sediments from Haihe River and the near-sea area of Bohai Bay than in those from the deep-sea area. The ?? diversity values were significantly higher, while Jaccard indexes of similarity were much lower among non-contiguous pairs of sites as compared with the contiguous ones. Cluster analysis indicated that quinone profiles may be grouped into two main clusters (sites 1?C7 and sites 8?C11), and there were higher similarities within the groups than between groups. Quinone species composition varied at different sites. Ubiquinones such as UQ-8, UQ-9, and UQ-10 and menaquinones such as MK-6, MK-7, MK-8 were isolated from all the sites and accounted for the largest proportions. Pearson correlation analysis revealed that both the number of quinone species and DQ correlated positively with total organic carbon contents in water and sediments, but negatively correlated with salinity and electroconductivity and did not correlate significantly with heavy metal contents in water. 相似文献
864.
Liu Jinfeng Yuan Dong Lu Ming You Yong Zhang Guangze Feng Tao Wang Dong Lin Zhiheng 《Environmental Fluid Mechanics》2021,21(6):1253-1271
Environmental Fluid Mechanics - Experimental tests were conducted on a rectangular flume with different grid-type dam grid sizes, channel slopes and debris flow bulk density. We use the Bernoulli... 相似文献
865.
866.
867.
Industrial symbiosis, a subfield of industrial ecology, focuses on transforming the waste of one firm into the valuable input of another, which improves the competitive advantages of supply chain by reducing production cost and improving environmental performance. Considering the specific situation where there are so many state-owned big company groups in China, this paper utilizes the ideas of constructing an industrial symbiosis among different firms, and does a case study on applying the concept into the inner relationships' reconstruction among different production systems in a big state-owned smeltery in South-west China. Three kinds of approaches are explored: 1) recycling and reusing the release; 2) concentrating and abstracting metals from the residues; 3) extending the product chain for value-added products. The results show that it can effectively improve the competitive advantage of the enterprise in terms of decreasing production cost and improving environmental performance. 相似文献
868.
针对提钒炼钢厂建设于20世纪70年代初的1号—3号转炉实施煤气回收的可能性进行了论证,对影响煤气回收的问题提出了相应的完善措施,在此基础上成功实施了1号—3号转炉煤气回收改造,改进后年回收转炉煤气达2 127 138GJ以上,可发电59 124 kW.h,减少CO2排放量近20万t,对降低生产能耗及减少温室气体排放起到了较好作用。 相似文献
869.
为了研究谷物粉尘燃烧特性影响因素,以可食用玉米淀粉为研究对象,通过ZY6243锥形量热仪(CONE)进行了单因素和正交试验,研究了粉尘粒径、惰性介质CaCO3质量分数、热辐射通量对玉米淀粉燃烧特性的影响效应。应用直观分析法和方差分析法定性地研究了各因素对玉米淀粉热释放速率峰值的影响程度并进行了排序,2种方法得出的结论基本一致。研究结果表明:各因素对玉米淀粉热释放速率峰值的影响程度依次为:CaCO3质量分数>粉尘粒径>热辐射通量;其中惰性介质CaCO3对热释放速率峰值和引燃时间的影响最为显著。 相似文献
870.
Yang Shaomei Yuan Aijia Yu Zhengqin 《Environmental science and pollution research international》2023,30(5):11689-11705
Environmental Science and Pollution Research - The randomness and instability of wind power bring challenges to power grid dispatching. Accurate prediction of wind power is significant to ensure... 相似文献