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Graphene oxide (GO) was prepared by modified Hummer’s method, and reduced by solvothermal method using ethanol as the solvent and modified diethylene triamine (amine curing agent 593) as reducing agent and modifier. The effect of reduction time and temperature on the structure and conductive property of reduced graphene oxide (593-rGO) was investigated by SEM, FT-IR and XRD. The results show that the graphene modified by 593 is obviously improved in dispersibility and sedimentation stability in dichloromethane, as well as in conductivity. The optimal reduction processing is that the mass ratio of GO to 593 is 2:1, the reduction time and temperature is 6 h and 160°C, respectively.

The poly (sodium acrylate/acrylic acid) water-absorbing resin was prepared by aqueous solution polymerization with acrylic acid (AA) as the monomer, calcium carbonate as the modified additives, N, N-methylene double acrylamide (NMBA) as cross-linking agent, ammonium persulfate (APS)/sodium sulfite oxidation reduction type initiator. It was found that the adsorption performance of absorbent resin modified by calcium carbonate strengthened obviously. Orthogonal and single factor experiment were used to establish the optimum parameters related to the product preparation. The best process conditions on water-absorbing properties of the modified resin was obtained. Using 150mL acrylic acid as a benchmark, the result show the optimum process conditions: the reaction temperature is 55°C, the mass fraction of monomer is 20%, the neutralization degree is 45%, modified additive dosage is 10 g, the dosage of cross-linking agent is 0.1%, and the initiator dosage is 2.0%, respectively. After made under the optimum process conditions, the water-absorbing rate of the modified resin was 676.6 times the dry weight.

In this study, three bio-electrokinetic remediation experiments were carried out to study the external delivery of oil-degrading bacteria by electrokinetics and enzyme activities in saturated soil. Results showed that the oil-degrading bacteria could efficiently transport to the saturated oil-contaminated soil by electrophoresis and/or electroosmosis. Bacterial population increased from 6.02-7.75 log (CFU/g) in the control experiment to 8.53-12.83 log (CFU/g) after external bacterial delivery. Under unidirectional operation, the bacterial populations near the electrodes were lower than those in the middle of the soil as a result of unfavorable pH environments. In bidirectional experiment BEK-B, a relatively low bacterial population in the middle of the soil was observed after the experiment. The activities of catalase, polyphenol oxidase, and dehydrogenase have similar trends with bacterial population in the soil, indicating a good relation between the three enzymes and oil biodegradation of oil in soil.

Bio-electrokinetic remediation of oil-contaminated soil is a promising technology. In this study, three bio-electrokinetic remediation experiments were carried out to study the effects of external addition of oil-degrading bacteria by electrokinetics and different operational parameters on oil decontamination in saturated soil. Results showed that oil in soil migrated from the anode towards the cathode with forward electroosmotic flow and accumulated near the cathode. Oil was barely degraded without external addition of oil-degrading bacteria. Although electrolytes were refreshed every 12 hr, soil pH varied greatly at the electrodes under unidirectional operation. When electrode polarity was reversed every 2 hr, soil pH was efficiently controlled within the range of 6.35-9.75. The relative oil concentrations after the bidirectional experiment were in the range of 0.81-0.84 after 20 days of treatment. The relatively low oil degradation rate may be due to the facultative aerobic environment in the saturated soil matrix.

With the development of modern technology, high quality power supply becomes more desirable in everyday life. Among problems related with the power quality, the most urgent is the voltage dip; with the application of power electronics devices, the power system is polluted by harmonics. SMES (Superconducting Magnet Energy Storage) system can not only compensate the voltage dip, but also provide a load-fluctuation compensation and active power filter. In the paper the main structure of SMES system is introduced; the necessity to use SMES are demonstrated by analyzing the problem of power quality. The analysis shows that SMES system is effective in improving the power quality.

Due to their significant impacts on the environment and health, there has been a growing environmental concern on sulfur oxide (SOx), nitrogen oxides (NOx) emissions to the atmosphere in the past two decades. Flue gas at coal-fired power stations is one of the main sources for the emissions of SOxand NOx. More and more stringent regulations on the emission of these pollutants come in force, which have put a high pressure on coal-fired power generators. Cost-effective and sustainable technologies for the reduction of such pollutants from flue gas have become increasingly important nowadays. However, even though numerous attempts have been made aiming at developing technologies for the removal of SOxand NOx, not much effort has been made on the simultaneous conversion of NOxand SOxin flue gas via selective catalytic reduction. This paper presents the study of simultaneous removal of SO2and NO over a synthesized Cu/Na-13X zeolite catalyst using carbon monoxide as a reducing agent. The characterization of fresh and spent catalysts was carried out using X-Ray Diffraction (XRD) and Brunauer-Emmett-Teller (BET) Surface Area Analyser. The experiments on the selective reduction of SO2and NO were carried out using a multi-functional catalyst testing rig with an online flue gas analyser. It has been found that zeolite has a good capability of SO2adsorption even under elevated temperatures. The removal efficiency was found to be 100% for SO2and 89% for NO over a Cu/Na-13X zeolite catalyst.

Nonlinear finite element model is established for the square interior constrained concrete filled steel tube column based on the research of the element type and material constitutive relation with finite element software ANSYS to find out the influence of the thickness of the steel tube, location of studs and geometry of the stirrups on the compression capacity of the short column, The results show that the compression capacity of the short column has something to do with the thickness of the steel tube and the studs, but the stirrups can eventually enhance a lot for the compression capacity as the validity is confirmed for the coherence of the results stepped from the finite element model and in test.

Based on the structural characteristics that the distribution of mass and stiffness is symmetrical in staggered truss structure, the load-carrying performance of staggered truss structure is equivalent to a pressure-bend combinational strut in this paper. By analyzing the relationship among curvatures , bending moments and shear forces of the pressure-bend combinational strut, the balance differential equations of the pressure-bend combinational strut is erected. Based on Runge-Kutta method, the lateral iteration equation derived by considering the influence of the second-order effects is derived. This paper analyzes the lateral displacements of floors of the staggered truss structure examples considering second-order effects or not, and gives a comparative analysis with the existing finite element software Ansys. The results show that the calculation method of second-order effects proposed in this paper has a good precision.

Coronary heart disease (CHD), called “thoracic obstruction” in TCM, is one of the most important types of heart disease for its high incidence and mortality. The methods of syndrome studies in TCM can not be completely in accordance with these of modern medicine because of the complexity itself. In this paper, we investigated the ability of Artificial Neural Networks (ANNs) to predict CHD patients with or without qi deficiency syndrome. Predictions with Multilayer Perceptron Neural Network (MPLNN, one type of the ANNS), we obtained recognition patterns made up of eight biological parameters. The accuracy of this recognition pattern was 82.2%, and the accuracy of validation pattern was 80.0%.

To investigate the causations why the tensile performance index of carbon fiber composite in use is generally under that offered by the manufacturer, the tests on the tensile characteristics of the carbon fiber monolayer and those of the gumming carbon fiber monolayer were carried out in this paper. Based on the test results and mixed principle of the relation between strength of composite and each of the components, the influencing factors on the drop in tensile performance index of the carbon fiber composite in use were analyzed. It is concluded that all kinds of the defects could reduce the local strength of composite materials. Internal defects of the composite, possible load eccentricity in the test, size effect of the composite sample, and tensile properties of the resin may be the primary influencing factors.