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Xu H.,East China Normal University | He G.,East China Normal University | Liu W.,East China Normal University | Liu G.,East China Normal University | And 2 more authors.
Chinese Journal of Environmental Engineering | Year: 2015

The feasibility of using an invasive plant Alternanthera philoxeroides to prepare activated carbon was investigated in the present study. Results showed that the order of the controlling factors for the yield and iodine number of the synthetic activated carbon was carbonization temperature > carbonization time > impregnation time >impregnation ratio, and the first three factors had significant impacts. The optimal preparation conditions were 4:1 for impregnation ratio; 6 h for impregnation time; 873 K for carbonization temperature and 1 h for carbonization time, under which the activated carbon prepared from alligator weed had a yield ratio of 37.44% and iodine adsorption amount of 752.36 mg/g. The surface area, the total pore volume, the average pore size and the ratio of mesoporous were 1 100.720 m2/g, 0.610 cm3/g, 2.216 nm and 72.00%, respectively. FT-IR analysis revealed that abundant functional groups were formed on the surface of the prepared activated carbon, including carboxyl, phenol and ether group. These results indicated that A. philoxeroides might be a promising biomass material for the preparation of mesoporous activated carbon. ©, 2015, Science Press. All right reserved. Source

Zhong Y.,East China Normal University | Liu Q.,East China Normal University | Liu C.,East China Normal University | Su Z.,East China Normal University | And 5 more authors.
Acta Theriologica Sinica | Year: 2014

Jiuduansha, currently in the succession stage of herbaceous plant community, are newly emerged islands in the Yangtze River estuary, and it was confirmed in 2008 that Rattus norvegicus had colonized the Jiuduansha Wetland. In order to know the effects of burrowing activities of introduced Rattus norvegicus on plant communities and soil in the Jiuduansha Wetland, we measured plant coverage, plant density, plant height, plant species importance value, plant species richness, plant species evenness, plant species diversity, moisture content and electroconductibility of topsoil between burrowing and non-burrowing areas. We also investigated the spatial relationship of burrowing locations and tidal creeks to explore the habitat selection strategy of Rattus norvegicus. The results showed that the burrowing activities of Rattus norvegicus reduced the coverage and height of Phragmites australis within Phragmites australis monoculture communities; and reduced the density, relative density, community coverage and importance value of Phragmites australis while increasing the density, coverage, relative density, relative height and importance value of Scirpus mariqueter in Phragmites australis-Scirpus mariqueter mixed communities; and increased the relative density, relative coverage and importance value of Tripolium vulgare and community species diversity while reducing the density and coverage of Spartina alterniflora and community coverage in Tripolium vulgare and Spartina alterniflora dominated communities. The burrowing activities of Rattus norvegicus reduced moisture content and electroconductibility of topsoil. Rattus norvegicus prefer to burrow near the edge of tidal creeks, which may contribute to its fitness. Introduced Rattus norvegicus could affect vegetation structure and succession of Jiuduansha by burrowing. Source

Xu H.-M.,East China Normal University | He G.-F.,East China Normal University | Dai L.-L.,National Engineering Research Center for Urban Pollution Control | Dai L.-L.,Tongji University | And 6 more authors.
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2016

The scientific gap of operating parameters of combined thermal and ultrasonic disintegration at low temperature of waste activated sludge (WAS) still needs to be filled. This study provides more insights into the technical feasibility of low organic WAS disruption pretreated by combined thermal at temperature lower than 100℃ and ultrasonic technique. Optimization of combined thermal and ultrasonic disintegration of WAS for enhanced organic releasing was carried out using response surface methodology (RSM) and Box-Behnken design of experiment. The quadratic effects as well as the interactive effects of temperature and specific energy on the disintegration degree of SCOD, soluble concentration of protein and carbohydrate were investigated. Results indicated that quadratic effect of temperature was more significant in affecting sludge disintegration than specific energy and regression models had good fitness with experimental results. The optimum disintegration degree of SCOD, soluble concentration of protein and carbohydrate achieved were 39.01%, 1360.59 mg/L and 334.52 mg/L, respectively, at 80℃ and 12000 kJ/kg TS. In addition, the verification experiments appeared high coincide degree with predicted results, indicating that the models were reliable for application and promotion of combined thermal and ultrasonic disintegration. © 2016, Chinese Society for Environmental Sciences. All right reserved. Source

Zhu L.-F.,East China Normal University | Zhu L.-F.,CAS Shanghai Advanced Research Institute | Zhu L.-F.,Shanghai Key Laboratory for Urban Ecological Processes and Eco Restoration | Sun J.-Z.,CAS Shanghai Advanced Research Institute | Zhang C.-J.,East China Normal University
Yantu Lixue/Rock and Soil Mechanics | Year: 2012

A general principle, a practical method and a modeling process of three-dimensional solid models for sedimentary stratigraphic systems are discussed. Based on the structural characteristics of the sedimentary stratigraphic system, a new approach for generating 3D solid models from borehole data, termed the "boreholes-surfaces-solids method", is presented and described. At first, a topologic dimidiate data structure is used to discretize borehole data into a series of scattered points. And then, the initial elevations of the top and bottom surfaces for each stratum are interpolated to automatically deduce the genesis of the missing strata. According to different geological geneses, surfaces intersecting, elevations adjusting and consistency processing are performed automatically on the missing strata's surfaces and their control surfaces. Finally, the solid model filled with 3D blocks or triangular prism meshes is built. A concrete example of using the "boreholes-surfaces-solids" method to Shanghai's construction projects is presented; and it is shown that this method is effective. Source

Lin Q.,East China Normal University | You W.H.,East China Normal University | You W.H.,Shanghai Key Laboratory for Urban Ecological Processes and Eco Restoration | Xu F.J.,East China Normal University | And 2 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2014

Dishui Lake is the largest artificial lake in Shanghai, China. Water in the lake comes from the Huangpu River via the Dazhi River through surrounding river networks, accepts surface runoff and passes through a sluice into the East China Sea. The lake is important for flood control, drainage, water replacement and other functions, and is critical to the Lin’gang New District’s landscape and to Shanghai’s eco-city construction. It is a newly formed lake with a fragile ecosystem and could easily be affected by external pollutant sources. Zooplankton play an important role in lake ecosystems and biological productivity at the base of the food chain since they eat phytoplankton, bacteria and detritus and provide food for fish and other aquatic organisms. Filter-feeding fish were put into the lake in recent years to control phytoplankton numbers, but a growing filter-feeding fish population could harm the zooplankton community. Consequently, long-term monitoring of variation in the zooplankton community is vital to the health of Dishui Lake. In order to explore the relationship between zooplankton community structure and environmental factors in Dishui Lake, we investigated the species composition, density and biomass distribution, dominant species of zooplankton and water quality parameters in Dishui Lake. We used eight sampling sites and took samples monthly from January to December, 2012. We identified 61 species belonging to 33 genera, including 45 Rotifera belonging to 22 genera, 7 Cladocera belonging to 4 genera and 9 Copepoda belonging to 7 genera., Dominant species included Copepoda species Limnoithona sinensis and nauplii, ten Rotifera species, while Cladocera had no dominant species. Dominant species were different in each season. The annual average density of zooplankton was 1200 ind./L and the annual average biomass was 1.67mg/L. Zooplankton species number, density and biomass were all higher in spring and summer than in autumn and winter. The annual average of Shannon-Wiener and Margalef diversity indices were 1.61 and 1.01 respectively. Both of these diversity indices were significantly different in different seasons, but not significantly different between the eight sampling sites. Pearson Correlation analysis, Multiple Regression Analysis and Redundancy analysis (RDA) of species number, density and biomass of zooplankton and environmental factors displayed a significant relationship between zooplankton community and environmental factors. This indicated that the seasonal variation of zooplankton community structures in Dishui Lake was closely related to the water eutrophication status. Water temperature was a key factor in variation in the zooplankton community structure, and chlorophyll a, pH, total nitrogen (TN) and total phosphorus (TP) were also important factors. Zooplankton species number, density and biomass increased with a rise in water temperature and a decline in pH. TN increased the density and biomass, but excess TP tended to reduce the number of species present. Several methods were used to assess the water quality and eutrophication levels. Results showed that the water quality status of Dishui Lake in 2012 could be classified as α-mesosaprobic and its eutrophication level was at semi-eutrophic levels under a comprehensive application of the water quality index, trophic level index (TLI) and diversity indices assessment methods. © 2014, Ecological Society of China. All rights reserved. Source

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