Applied Mechanics and Materials Vols. 260-261

Abstract: This study chooses the industrial wasteland after the relocation of a metal processing factory in Shenyang, Liaoning Province of China as the research object. Based on level three soil heavy metal quality standards of Soil Environment Quality Standard (GB15618-1995) in China, the pollution levels of four heavy metals (cadmium, lead, copper and zinc) in survey area are Cd> Cu> Zn> Pb; the Cd pollution is the most serious one, followed by Cu and Zn. The Pb content is low. Average comprehensive pollution index of Cd, Cu, Zn and Pb in soil of the wasteland is 17.33, which belong to Grade V severe pollution. The most polluted point is J-12, followed by J-11 and J-16. The land utilization risk assessment of the wasteland should be strengthened, and appropriate and necessary repair measures should be taken, such as planting accumulative or tolerant plants.

Abstract: Toxicity of As on soil neutral phosphatase was studied through a series indoor incubation experiments. Results showed that the activity of soil neutral phosphatase was significantly inhibited by As pollution, and the peak inhibiting ratio was appeared at the sixth incubation day. While the activity of soil neutral phosphatase was also decreased with concentration of As increasing in the same incubation day. The relationship between the concentration of as and soil neutral phosphatase was fit by model ①y=c/(1+bx)and ②y=c(1+ax)(1+bx).The model② was more suitable to describe the relationship between the concentration of As and soil enzyme. This means the effect mechanism of As on the soil neutral phosphatase was part of inhibition. The Km of neutral phosphatase was increase by As concentration adding, while the Vmax was lowered. This kind of inhibition belongs to mix competition inhibition. Phosphatase widely exists in the biological world, from lower organism Escherichia coli, yeast to higher animals and plant tissues, body fluid and human liver, prostate gland are found to have phosphatase exist. It can catalyze the phosphate hydrolysis of elemental and inorganic phosphate release, important enzymes of biological phosphorus metabolism [1-2]. Soil phosphatase is an enzyme that has a major impact on agricultural production, producing an important role in the cycle of soil phosphorus. Research show that phosphatase in soil and aquatic systems of phosphorus, organic phosphorus pesticide contaminated soil bioremediation is very important, so it can be used as material for ecosystem beneficial or deleterious effects of indicator. Therefore, some can be as the instructions of the beneficial or harmful effects of ecosystem biology. Arsenic is widespread nature of toxic heavy metals often pollute the environment with the waste material, pesticides, fertilizers and other. According to the statistics in early 1990s, each year around the world due to human activities the importation of soil arsenic content of 0.52-1.2 million tons, its impact on soil ecosystem is one of the important topics. This experiment which proposed indoor simulation method analysis different concentrations of arsenic contaminated soils of neutral phosphatase activity, to explore the effects of different concentrations of arsenic on soil phosphatase activity of short-term toxicity effect. Analysis of the influence degree and duration, further analysis between the two possible mechanism, provides the basis for environmental protection and monitoring.

Abstract: This paper studies on the electromagnetic transient model of doubly-fed wind turbinegrid-side converter under the imbalanced grid condition. And on this basis, the paper analysis theimpact of doubly-fed converter when grid voltage asymmetric drop. It puts forward a dual PLL anddual current control combination of doubly-fed converter grid side control strategy. This strategyachieves grid voltage positive and negative sequence fast separation when asymmetric grid voltagedrop occur, achieves the active output power secondary fluctuate suppression under the imbalancedgrid voltage condition, avoids DC voltage rise at the fault moment and also achieves converterreactive power support under the imbalanced grid fault. The simulation and experimental resultsshow that the proposed control strategy is correct and with the application value of engineering.

Abstract: The effects of catalyst amount on the yields of levulinic and hydroxymethyl furfural were investigated during conversion of glucose to levulinic acid catalyzed by ZSM-5. XRD and XPS were used to analyse the characteristics of ZSM-5 before reaction and after reaction. The results showed that: ZSM-5 exhibited good catalytic activity in the reaction of hydrolysis of glucose to produce levulinic acid. The characteristic peak of ZSM-5 molecular sieve did not change after reaction compared to that of before reaction. The relative crystallinity of ZSM-5 decreased after reaction, which caused the catalytic activity decline. The surface O, Si and Al content of ZSM-5 decreased greatly. The increase of element C was the main reason of inactivation of catalyst.

Abstract: The average concentration of H₂S in Changqing oil Field is higher than 100mg/m³,which is much higher than the demand of “Operational Site Harm Factor Occupation Contact Limiting Value” (GBZ2-2002). Taking this factor into consideration, the experiment aimed at reducing H₂S concentration in crude oil gatering and transferring systems by using the denitrifying bacteria. The experiment has two parts: First sulphat reduction process and then denitrification inhibit process. Therefore, two UASB reactors are used in a series to achieve these two processes. The first UASB reactor are mainly used to create SRB bacteria and H₂S gas .After the first UASB reactor successfully starting, sodium nitrite are added in the second UASB to achieve denitrification inhibit process. The experiment showed that after the first UASB reactor start, the S₂^- can achieve 120mg/L and SO₄^2- concentration is about 200 mg/L. So the Sulfate conversion rate can achieve 75%. Then, when the second UASB reactor started successfully, the S^2- concentration sharply droped into 20 mg/L and SO₄^2- concentration increased to 400mg/L, the sulphat reduction can achieve 83%. Also, advanced research showed that both SO₄^2-concentration ratio and ORP value can contribute to restraining the SRB bacteria.Finally，through DGGE technology,many kinds of bacteria take into this process, for example pseudomonas aeruginosa. The results of this experiment has a great value to refrain the concentration of H₂S in oil fields.

Abstract: The paper deals with possibilities of decrease in CO₂ emissions in Moravian Silesian region, Czech Republic, typical of metallurgy industry. It analyses various kinds of technical and technological approaches of metallurgical industry to this problem. It discusses application of hydro – carbon fuels in iron -making process which seems to be technologically and economically beneficial alternative for blast furnace fuel. The paper devotes to hydrocarbon fuels application relating with the decrease in CO₂ emissions

Abstract: Corporate Environmental Supervisor System is established referring to Japan’s public pollution prevention manager system and combining the actual situation in our country. Looking at the existing environmental regulatory system, China has built a relatively perfect monitoring system for corporate environmental pollution control, but the internal corporate environmental management is weak, corporate social and environmental responsibility not strong, internal corporate environmental management organizational system unperfected and the rights, obligations and responsibilities of corporate environmental managers indeterminate. The establishment of the corporate environmental supervisor system helps and guides enterprises to designate an environmental management director filled by the owners of enterprises and an internal corporate environmental management system consisting of at-work environmental supervisors, and the supervision and inspection of all the aspects of production are conducted by the environment supervisors who grasp environmental laws and regulations and are familiar with the production technology and pollution discharge situation of their enterprises to extend the corporate pollution prevention from the end-treatment to the whole production process. This will effectively promote the enterprises to enhance the subject responsibility and comprehensively reduce the polluting emission. In this paper, the Necessity of China's environmental supervisor system, the theoretical framework and practice are discussed.

Abstract: There are various potential natural geological disasters in the process of tunnel construction, such as methane gas, tunnel collapse, tunnel gushing, etc. Due to the limited data collection and the invisibility of some natural phenomenon, how to simulate these geological disasters more visually and increase its early warning management more effectively has been a tough problem in three-dimensional simulation. This paper briefly describes the GIS-based three-dimensional rendering technology and the feature attribute management method to achieve the geological disasters modeling in the tunnel and its simulated prediction, which can provide auxiliary support for the decision of the safe construction of tunnel engineering.

Abstract: Minqin County is located at the arid inland area of China, and its oasis is one of the typical desert oases in China. As natural factors and human factors have brought many ecological environment problems, the causes of the deterioration of Minqin's ecological environment are analyzed and some countermeasures on the protection and treatment of its ecological environment are proposed in this paper.

Abstract: This paper combines the management and prevention of geological disasters through network technology to design the management and prevention platform of geological disasters in Jiangxi Province, which achieves the electronization of the organizational structure and workflow of geological disasters prevention and control on the Internet. This platform breaks the limitations of time, space and departmental separation and promotes geological disaster prevention and management to the level of continuous accumulation, scientific management and rational utilization. Also, Geological disaster prevention and control enters a healthy circulation of dynamic assessment, rapid response, remote consultation and emergency command. The system provides all-rounded high quality, transparent and efficient Web service of geological disaster Alerting, prediction, prevention and management information, achieving the purpose of improving the efficiency and quality of geological disaster prevention and management.