Applied Mechanics and Materials Vols. 209-211

Abstract: This paper present ecosystem destruction in Mianyang after the "5.12" Wenchuan earthquake and the role of ecological restoration and reconstruction, emphasize on vegetation restoration, soil ecosystem restoration, ecological benefits (structure and function) restoration and some other aspects, to discuss the countermeasure about ecological restoration and reconstruction, which provide references for ecological restoration and reconstruction in disaster areas .

Abstract: The city development goal of Harbin is described as be suitable for living, be suitable for venture, and be suitable for the comprehensive development of people. In recent years, Harbin residential environment construction has already been improved under the guidance of this development concept. The article summarized the advantages and disadvantages of our city’s residential environment basing on the overall investigation of representative 15 residential districts current situation, so as to provide the references to build the harmonious and boom residential environment.

Abstract: Through greenhouse pots experiments, an orthogonal test method was employed here to study the optimum degradation conditions of cold-adapted degrading bacterial and the winter wheat. This orthogonal experiment selected four influencing factors: oil content, bacteria amount, soil moisture content and fertilizer. The results showed that in different stages, the optimum degradation conditions were different. Oil content and the bacterial amount were the two most important factors that influenced the degradation of petroleum hydrocarbons. The impact of fertilizers on the degradation rate increased with time, while water content on the degradation rate decreased with time.

Abstract: The adsorption of Zn2+ from simulated seawater onto biomaterial derived from the macroalgae Sargassum horneri was investigated via batch experiments. The highest adsorption rate was 96.9%, which found in the lower Zn2+ concentration solution where pH was 8.0 and temperature was 15°C, and the maximum adsorption capacity of dead Sargassum horneri particle to Zn²⁺ could arrive to more than 0.20 mg.g^-1. Sargassum horneri pretreated with CaCl₂ can increase the adsorption rate. Infrared analysis results showed that carboxylic acid groups have an important contribution to Zn²⁺ adsorption. The adsorption equilibrium of Zn²⁺ could be represented by pseudo-second-order model and the capacity of dead alga for Zn²⁺ was approximately constant. Conclusions could be drawn that Sargassum horneri is a kind of efficient biosorbent for the treatment of waste waters containing heavy metals. It was because Zn²⁺ can easily be desorbed by competition between the hydrogen ions and metal ions on the cell surface binding sites, that hydrochloric acid was proved to have economic feasibility.

Abstract: The Risk Based Corrective Action (RBCA) Tool Kit for Chemical Releases was used to develop Soil Screening Levels (SSLs) for contaminated sites assessment in Beijing. A total 88 contaminants, including inorganic compounds, volatile organic compounds, semi-volatile organic compounds, pesticides, polybrominated biphenyls and others, were identified as the priority compounds of concern, and a range of exposure parameters, toxicological data and site factors based on the environmental monitoring data from several contaminated sites in Beijing, were used as model inputs to derive SSLs. The proposed SSLs were evaluated and validated by comparing with corresponding values in some other countries/regions. The present study has an important guiding significance for the development of risk-based SSLs in other provinces/cities of China.

Abstract: In this study, the problems of researches for healing environment were analyzed and the resolve methods were proposed. We reviewed a great quantity of research papers which covered 4 fields - medical field, geography field, landscape gardening field, and architecture field as the database. Further, we pointed out the weak points on research background, research method, research target, research content and phraseology of detail elements. Meanwhile, we proposed the resolutions for resolve the weak points, such as the research content for reclassifying with characteristic and normalization methods for words. This research provided the basic method to healing environment research provides. It has significant for the research about healing environment in the future.

Abstract: The dewatering and mineralization of sludge in the constructed reed bed was investigated in this study.The sludge from the secondary sedimentation tank is from in the wastewater treatment plant in Yiyang city,Hunan province.Anaerobic pond and oxidation ditch biological treatment processes is accepted there.The performance of the system was monitored for one year. Total Solids (TS), Volatile Solids(VS), Chemical Oxygen Demand, nutrients (TKN) and Total Phosphorus(TP), heavy metals in the sludge were analysed.The removal rate of COD,NH4-N,and TP of the percolated fluid for the first cycle was also monitored. TS content reached 36.5% for the surface layer and 37.8% for the bottom layer at the end of the examination period.Sludge stabilization in the bed was also observed(VS content decreased to 31.3% and 13.4% respectively for the surface and bottom layer).Concentration of nutrients of the sludge accumulated in the bed also decreased. The heavy metal concentration meets the European Union standards for heavy metals in case of agricultural disposal of the treated sludge.

Abstract: For lead-zinc polluted soil, the sources, formation, harm, transformation of heavy metals were summarized. Relative policies, contaminated soil type, remediation standard, remediation technologies and existing problems were studied, providing reference for Chinese lead-zinc polluted soil remediation.

Abstract: Using the two periods of TM images and investigation of Hulun Lake, vegetation index, TS, NDMI, NDSI, slope are choosed as indicators. Grassland eco-environmental quality assessment model is builded by multiple linear regression to assess quality in the study area. From the evaluation results, poor and bad area increased from 9% to 17%, meanwhile, good and general area decreased from 89% to 81% in five years. The grassland eco-environmental quality in the study area is getting worse and worse.

Abstract: This article integrate the theoretical calculation of the power-frequency electromagnetic field intensity and radio interference intensity under transmission line, and analyze the factor which influence the value and distribution of the electromagnetic field, radio interference under transmission line, aiming to provide basis and reference for other environmental assessment of electromagnetism. The study shows that a reasonable selection of analog lines can get an accurate result as the theoretical calculation. Important factors of analog lines selection including: grade of voltage, current, height of line, location order of line, number of circuit, section area of line, number of bundle conductors.