Advanced Materials Research Vols. 1065-1069

Abstract: Sludge Concentration (MLSS) is one of major parameters for operation of Anoxic/Aerobic-Membrane Bioreactors（A/O-MBR）and it influences the removal efficiency of pollutants and the rate of membrane fouling as well. This paper focuses on the effects of different MLSS on the treatment of domestic wastewater, the quantity and composition of extracellular polymeric substance (EPS), and the variation of the rate of membrane fouling. It also includes a preliminary analysis of the correlation between EPS and membrane fouling to provide reference for future studies of the mechanism of membrane fouling.

Abstract: Polyacrylonitrile (PAN) ultrafine fiber was prepared by electrospinning of PAN solution made from waste PAN. Diameters of the electrospun fibers as well as distribution of them were characterized by scanning electron microscope. The results show that the waste polyacrylonitrile/ N,N-dimethylformamide solution can be used for electrospinning after simply treatment-filtration. Uniform ultrafine fibers with diameters between 100 nm and 250nm could be obtained. With increasing concentration of waste PAN from 9% to 10%, the morphology was changed from beaded fiber to uniform fiber structure and the fiber diameter was also increased from110nm to 184 nm gradually. A narrow distribution of fiber diameters was observed at a voltage of 22kV. However, more beaded fibers were observed for longer tip–collecting foil distance.

Abstract: Potentials of three plant species, rape, alfalfa and white clover, separately or jointly on the degradation of polycyclic aromatic hydrocarbons (PAHs) in soil were estimated by pots experiments. Results showed the presence of vegetation apparently enhanced the dissipation of PAHs at initial concentrations ranging from 20.05 to 322.06 mg·kg^-1. Within 70-day experiment, alfalfa and white clover showed higher efficiencies for removal of PAHs than those of rape, and mixed cropping greatly enhanced the dissipation of PAHs as compared to single cropping. On average 74.87% of phenanthrene or 62.81% of pyrene were removed from soils with mixed cropping of rape and alfalfa, and 72.01% of phenanthren or 68.44% of pyrene removed by mixed cropping of rape and white clover. Results suggested a feasibility of the establishment of multispecies remediation for enforcing the dissipation of PAHs.

Abstract: The removal of persistent organic pollutants (POPs) in soils at initial concentrations ranging from 20.00 to 321.05 mg·kg^-1 was investigated under different planting patterns, and enhancement mechanisms were analyzed. Results showed that the dissipation of POPs in soils growing Brassica campestris and Medicago sativa significantly exceeded those vegetating single species. During 70-day experiment, about 75.06% of Pyr and 68.22% of BaP was removed from the soils under mixed cropping; while only 31.8% and 64.03% of Pyr and 27.84% and 51.93 of BaP were removed under single rape and alfalfa cropping, respectively. Of all pathways enforcing POPs removal, plant-microbial interactions is the most predominant. These results suggested a feasibility of the establishment of multi-species phytoremediation for improvement of the remediation efficiencies of POPs, which may decrease accumulations of POPs in crops and thus reduce their risks.

Abstract: A spatial and temporal distribution of PM_2.5 as one of the most critical pollutants in Beijing was studied for the whole year 2013. In this pre-research work the spatiotemporal variation of PM2.5 in studied over metropolitan area of Beijing in 2013. More over a weighted transportation influence ( WIT) is defined to monitor the role of transportation in PM2.5 pollution. The results show the remarkable effect of transportation in PM2.5 concentration (R²=0.75). Plus, with this research, we give more information about the source of high PM_2.5 concentration in Beijing, and suggest to control this matter transportation is one of the notable source which requires more attention from decision makers.

Abstract: Based on technology of Geographic Information System, Geographic Position System and Remote Sensing, land ecological status of coal mining subsidence in Huang Huai Hai area is investigated and evaluated. The investigation and evaluation database for land ecological status of research area is constructed after field survey and information extracted from the current land ecological condition in this paper. Research results in this paper can be used to restore the land ecosystem of coal mining subsidence in Huang Huai Hai region.

Abstract: This article firstly summarized the main progress and achievements in land ecological security research, which include field, object, driving factors and evaluation method. Secondly, it pointed out some problems and put forward that special attention should be paid to following trend in the future study of land ecological security. And finally, the purpose of the article is to further improve people's understanding and attention of land ecological security and to provide a scientific basis for the further research of land ecological security.

Abstract: Effects of the sorts and concentration of flocculants, types of PAM and pH value on the advanced treatment of Vitamin E production wastewater by magnetic flocculation process were studied. When the effective flocculant prepared in our lab was chosen as the flocculating agent and its concentration was 1.0 g/L, The cationic PAM 802 was as the coagulant aid and its concentration was 15 mg/L, pH was controlled as 9.0, COD_Cr removal rate achieved the maximum of above 31%.

Abstract: A biotrickling filter has been set up in WWTP of Nanjing petrochemical factory for about 6 months. The purpose of this project was to assess the ability of the biotrickling filter to remove hardly biodegradable VOCs such as benzene, toluene, ethylbenzene and xylene which are recalcitrant and poorly water soluble and commonly found in petrochemical factories. PUF cubes (1 cm3) were used as the packing media treated with large amounts of circulating mineral salt medium added with bacterial species which came from secondary sedimentation tank of WWTP of Nanjing petrochemical industry. The controlled empty bed retention time (EBRT) of 90 s was a key parameter for reaching a removal efficiency of 91.7 %, 88.3 %, 70.7 % and 63.5 % for toluene, ethylbenzene, benzene and xylene, respectively. The analysis of the bacterial community in the BTF during VOC removal showed that Pseudomonas putida and Klebsiella sp. phylum were dominant microbes.

Abstract: The content of PM10 and PM2.5 in public places can harm to human health. Conduct the PM10 measurement in three public places of Qinhuangdao Kindergarten, Office Building and College Classroom. According to the measurement data statistics, analysis the influencing factors of indoor environmental pollution. The results showed three conclusions. First, the indoor PM10 concentrations influenced by the indoor whether heating or not. The PM10 concentration change ratio is 1.12~ 1.663, and the PM2.5 concentration change ratio is 1.29~2.1. Secondly, in the fog haze weather, indoor PM10 concentrations linear associated with outdoor PM10 concentrations; in the sunny day, there was no obvious correlation with the outdoor PM10 concentrations. Finally, contrast the standard drawn up by domestic and foreign relevant organizations and authorities, in the fog haze weather, indoor PM10 and PM2.5 concentrations below China standard value, but higher than USA, Europe, Japan standard value.