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Decontamination level and residual amount of polycyclic aromatic hydrocarbons (PAHs) were investigated by ex-situ remediation technologies including biopile, soil washing and thermal desorption in a field level. After the remediation, 16 USEPA priority PAHs were decontaminated from 99.3% to 99.9% for thermal desorption, from 17.9% to 82.1% for biopile and from-27.6% to 84.3% for soil washing. Residual PAHs amount in soils by thermal desorption was below the local soil screening level, differently from that by biopile and soil washing. Especially for high molecular weight PAHs, i.e. 5-6 rings PAHs, residual amount exceeded over the screening lever 4 to 197 times for biopile and 17 to 421 times for soil washing. Additional factors, such as cost, time, operation and maintainance etc. for remedial technology selection and contaminant bioavailability in soil matrix for remediation target values, were proposed to be paid more attention for specific contaminated sites.

The effect of the field oxidation process on the electrical characteristics of 6500V 4H-SiC JBS diodes is studied. The oxide thickness and field plate length have an effect on the reverse breakdown voltage of the SiC JBS diode. According the simulation results, we choose the optimal thickness of the oxide layer and field plate length of the SiC JBS diode. Two different field oxide deposition processes, which are plasma enhanced chemical vapor deposition (PECVD) and low pressure chemical vapor deposition (LPCVD), are compared in our paper. When the reverse voltage is 6600V, the reverse leakage current of SiC JBS diodes with the field oxide layer obtained by LPCVD process is 0.7 μA, which is 60% lower than that of PECVD process. When the forward current is 25 A, the forward voltage of SiC JBS diodes with the field oxide layer obtained by LPCVD process is 3.75 V, which is 10% higher than that of PECVD process. There should be a trade-off between the forward and reverse characteristics in the actual high power and high temperature applications.

In the rock pyrolysis experiment, part of the boiling point above 300°C of the high carbon number hydrocarbons and the hydrocarbon generated from pyrolysis of resin and asphaltene detected into S₂, resulting in the thermolysis residual hydrocarbon "S₁" is smaller than the real value, potential hydrocarbon generation of kerogen "S₂" is greater than the real value. Thus using the experimental pyrolysis parameters directly calculate the hydrocarbon expulsion efficiency is greater than the real value. We used the pyrolysis parameters before and after correction, combined with the method of the restoring of original hydrocarbon potential to calculate the hydrocarbon expulsion efficiency of mudstone of Qingshankou l member of well Xu 11 in San Zhao area of Song Liao Basin. The average of the expulsion efficiency before and after the pyrolysis parameters correction are 87.4% and 66.9%. The hydrocarbon expulsion efficiency have a great difference between before and after correction, thus the pyrolysis parameters correction is particularly important in the calculation of hydrocarbon expulsion efficiency.

Catalytic hydrolysis decomposition of dichlorodifluoromethane (CCl₂F₂) in the presence of water vapor and oxygen was studied over solid base Na₂O/ZrO₂ using a fixed-bed reactor. The CCl₂F₂ adsorption was multilayer chemical adsorption and its process was corresponding with Freundlich model. Its adsorption heat was from 43.74 to 76.31 KJ.mol^-1, and the CCl₂F₂ adsorption over solid base Na₂O/ZrO₂ was exothermic and chemical.

Aviation ad hoc network has dynamic topology and uneven distribution of nodes, so it is difficult to establish node-disjoint multipath routes. Aviation ad hoc network multipath routing of path segmentation based build multipath routes between source node and the destination node in path segmentation. Each segmentation has one to three concurrent paths established by the topology of network, through which it leads to loading equilibrium. To ensure the accuracy of the data transmission of links with hop-by-hop verifying transmission mechanism and to reduce the cost of frequently routing update and end-to-end delay with routing fragment strategy. Finally, the routing protocol is simulated with the simulation software NS2 and the result shows that it has a good performance.

Highly ordered TiO₂ nanotube array hasbeen widely used as the dye-sensitized solar cells’ (DSSCs) light anode material forits abilities of inhibiting electronic recombination at the interface and improving the beam transmission of the carrier. The morphology and structure of the nanotube would influence the efficiency of the cell. In thisstudy, TiO₂ nanotubes (caliber ranging from 50 to 150nm, length ranging from 0.9 to 4μm) were prepared by a two-step anodization method and the morphology of nanotubes was regulated bythe parameters such as oxidation voltage and oxidation time. The absorbing capacities of nanotubes were measured by the dye adsorption test and the corresponding photoelectric conversion efficienciesweremeasured too. The results indicated that the conversion efficiency was related to the specific surface area and length of the nanotube. The length of nanotube would increase with theoxidation time within acertain limit.Then thedissolution on the top of TNT would reduce nanotubes’ length and lead to the decrease of the specific area, eventuallyimpairedthe photoelectric conversion.

Application of probabilistic risk assessment (PRA) and deterministic risk assessment (DRA) at a coking plant site were compared. By DRA, Hazard Quotient (HQ) following exposure to Naphthalene (Nap) and Incremental Life Cancer Risk (ILCR) following exposure to Benzo(a)pyrene (Bap) are 1.87 and 2.12×10^-4. PRA reveals valuable information regarding the possible distribution of risk, and the outputs show that Nap HQ ranges from 6.18×10^-7 to 6.62 and Bap ILCR ranges from 8.67×10^-10 to 6.89×10^-4. Risk estimates of DRA locates at the 99.59th and 99.76th percentiles in the risk outputs of PRA, indicating the DRA overestimates the risk. Sensitivity analysis was done by calculating a contribution to variance for each exposure parameter and it is found that contaminant concentration in the soil (C_s), exposure duration (ED), soil ingestion rate (IR_s) are the most important parameters for risk calculations

Coal is a continuous unconventional gas reservoir and coal bed methane has the potential to make an important contribution to the future energy demands. The second member coal seam of Shaxi Formation in the Mengjin coalfield is one of the most important methane bearing and exploration formations. Based on industrial analysis, elemental analysis and methane content test of thirty-five coal samples from the Mengjin coalfield, together with other geological data of the past five-year exploration, the factors that controlling the coal bed methane reservoir are identified in the Mengjin coalfield. The thick-bedded No. 2 coal seam, about 6 meters, of the Shaxi formation are continuous distributed in the Mengjin coalfield. The burial depth is from 400 to 800 meters, this is suitable for coal bed methane exploit. There is a trend which an increase in the degree of coalification is correlated with rise content of methane in No. 2 coal. Coal rank has a significant effect on the content of coal bed methane. The relationships between methane content and basin hydrodynamics are also described and discussed in this paper. The deep stagnant zone contains the largest coal bed methane accumulation. Future geological exploration for coal bed methane in Mengjin coalfield should be guided by the essential factors identified in this study. The application of them could benefit to solving the discrepancy between the amount of reserves and the question of their exploitability.

The graphite was exfoliated by concentrated acid treatment, strong oxidants oxidation, high temperature rapid thermal shock process. Investigated in detail that the kind of oxidants, concentrated acid ratio, oxidation time affected on the graphite expansion rate. Experimental results (expansion, micro-structure observation and chemical structure analysis of graphite) showed that the optimum volume ratio of concentrated sulfuric acid and concentrated nitric acid was 4:1; the expansion rate was better that added oxidant KMnO₄ than added oxidant K₂Cr₂O₇; The best oxidation time (concentrated acid treatment time) was 30~60 min.

Food waste is rich in nutrients. It can be disposed safely by biotechnology, which can make a contribution to environment, and avoid wasting resources. The bio-reactive food waste disposal processor basing on aerobic composting technology is designed in the research. The miniaturization and practical of it can be realized by studying its integrated form and structural components.