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Poly (vinyl alcohol) (PVA) was used as the sole carbon source in the medium to isolate PVA-degrading fungi from an activated sludge which obtained from water-soluble PVA packaging film factory. The PVA-degrading fungi were screened after transparent circle experiment and were preliminary identified through morphology and optical microscope observations. The qualitative and quantitative researches of the effect of additives on PVA degradability were investigated by transparent circle experiment and UV spectrophotometry, respectively. The results showed that the degradation effect of the XP-02 was the best in ten PVA-degrading strain and was preliminary identified as penicillium. When the concentration of additives was 0.05 g/L, the biodegradation rate of PVA was increased with the addition of plasticizer (polyethylene glycol) (PEG), surface active agent (sodium dodecyl benzene sulfonate) (SDBS) and emulsifying agent (tween-80 or triton X-100) by 5.01%, 8.67% and 11.21%, respectively, which indicates that the additives in the PVA packaging film can increase the degradable effect. However, the optimum proportion of these additives in the PVA film to obtain the best degradability for the film is deserves the further investigation.

According to the characteristics of power emergencies and integrating the realities of grid emergency management, the paper established grid emergency management capability evaluation indexes system, which is consist of 1 first grade indexe,15 second grade indexes. First, the paper determined the weight of each index with AHP and then evaluated the indexes system by fuzzy comprehensive evaluation in two levels. In numerical example, the paper took a provincial grid company emergency management capability assessment as an example, obtained scientific analysis results, proved the usefulness of the evaluation system, and pointed a clear direction for the grid companies’ emergency management construction in the future.

Based on input-output feedback linearization scheme using the theories of differential geometry, this paper designed a controller for the continuous stirred tank reactor system which is a typical nonlinear, multi-variables, time-varying system. First, continuously different the chosen system outputs until control input appear in the expression. Then, overall linearization can be realized by input variable-substitution if some conditions are satisfied. At last, mature linear control theory is used to control the sub linear system stable. Simulation results show that the proposed control scheme is efficient and the system contains good static, dynamic performance.

In the process of thickened oil thermal recovery, the pre-stress cementing needs to be anchored at the bottom of the casing pipe. And the reliable opening and closing of anchor flukes directly influence the anchoring. In allusion to the problems of how to get the critical value of drilling fluid flow rate of when the anchor flukes begin to open, completely open, begin to close and completely close, whether different nozzles can open or close reliably, getting the corresponding differential pressure and discharge coefficient of the different nozzles, this paper conducts a study from both theory and experiment to obtain the relevant parameters. By simulating the anchor in actual work and dealing with the data, we conclude that: (1) The fluke can open smoothly when the flow rate reaches a certain flow and it can also close smoothly when the flow rate declines. (2) The critical flow rate of the flukes, when two kinds of anchors are with different nozzles, has been acquired. (3) Corresponding differential pressure and discharge coefficient of the different nozzles in different flow rate have been ascertained.

In this study, PVDF membranes were prepared by solution-cast method. The effects of evaporation temperature on the morphology, polymorph and mechanical properties of such prepared membranes were studied. It was found that perfect spherulites were observed in the solution-cast membranes. FESEM photomicrographs of the membranes showed dense structure. PVDF mainly crystallized into α phase. In the solution-cast process, the spherulite size increased as evaporation temperature was increased from 120 °C to 150 °C, when the evaporation temperature was 165 °C, spherulite size decreased. And the tensile strength increased with the decrease in spherulite size.

Cylindrical magnetic medium (rod matrix) serves as the carrier for magnetic particles in pulsating high gradient magnetic separation (PHGMS), which has been widely applied to beneficiate hematite, ilmenite, limonite, siderite, wolframite, etc., in the mineral processing industry and to purify wastewater. The arrangement of rod elements in the matrix plays a decisive role in the magnetic field distribution and in the movement of particles in the matrix, thus generating a significant influence on the performance of PHGMS. The effect of feed solids on PHGMS is investigated in the 3 mm rod matrix of different spacings between rods in a single matrix layer, by Slice-Matrix Analysis; it was found that there is a maximum feed solids for a given matrix; beyond this feed solids, the performance of PHGMS deteriorates significantly.

A village-scale approach was developed to break the cycle between desertification and poverty by providing sustainable employment and income, promoting environmental restoration by reducing water consumption, and integrating poverty amelioration with environmental restoration to ensure that solving one problem does not create new ones. The advantages of high-efficiency water-saving planting, a profitable livestock system, a sand-processing industry, and sand control and afforestation are integrated into what we call the Zhengxin pattern, which offers overall ecological and environmental benefits superior to those of competing approaches. The overall output efficiency of the Minqin basin water resources will increase threefold.

The experiments were done to find some good corrosion inhibitors for mild steel in 5% HF solution by the method of weight loss and electrochemistry including polarization curves and electrochemical impedance spectroscopy (EIS). Results show that the thiourea, potassium thiocyanate, and hexamethylenetetramine have good inhibition effect for mild steel in 5% HF solution, especially potassium thiocyanate and thiourea. Their corrosion resistance was greatly enhanced in the presence of tested inhibitor. Thiourea is an anodic type inhibitor and its inhibition efficiencies up to 99.88% can be obtained. Equivalent circuit of the investigated system was suggested.

The study was conducted in arbor forests, arbor-shrub forests and shrub lands in Karst peak-cluster depression areas. We investigated soil property and water-holding capacity in the three types of woodland by means of cutting-ring and water immersion. Our results show that soil bulk density presents an increasing trend along with soil layers deepening, while total soil porosity, capillary porosity and non-capillary porosity decrease. Natural water-holding capacity of soil, saturation water-holding capacity of soil, water-storage capacity of capillary and soil water storage capacity decline with deeper soil layers in all the three forests. Water-holding capacity and immersion time of soil meet the equation Y=kln (X)+b and the equation Y=k(X)-b fits water absorption rate and soaking time of soil well.

To reuse waste rubber tires is a global issue. One method of reusing tires is to process them into crumb-sized particles and produce crumb rubber modified asphalt (CRMA), which is a an effective way of reducing the pollution and resource utilization. Rotary viscosities of CRMA prepared under different conditions were measured to analyze the effects of treating methods, treating temperature, crumb rubber size, treating time and rubber dosage on the viscosity of CRMA. And a prediction model of viscosity of CRMA was developed. Test results indicate that, using the high-speed stirring method, viscosity of CRMA (η) appears quadratic function relationship with processing temperature (T) and crumb rubber mesh (D), exponential relation with the dosage of crumb rubber (R), but has no significant rule with the stirring time. By regression analysis, prediction model of viscosity of CRMA has a high viscosity fitting accuracy, which can provide a reference for production process of CRMA.

Based on the data display of instrument for the current electric vehicle is imperfect, this paper puts forward designing a generic electronic instrument of electric vehicle with speed, mileage and power data display function. The microcontroller of AT89C52 is the core of system design. The design uses Hall sensor as a speed detection sensor to realize the mileage/speed measurement display of electric vehicle. It uses the 24C02 saving the mileage information in case of power-down system, uses LED module in real-time displaying the speed, mileage and power, and provides the alarm function of hypervelocity. The design of the system is in real time, running well in the test, may be promoted to the electric vehicles research and development industry.

In order to investigate the effect of moisture content on thermal physical properties and heat transfer of plywood during hot pressing, the quasi steady method was applied to measure the thermal conductivity, specific heat and thermal diffusivity values of the resinated plywood assembly with a UF loading rate of 300g/m2 under different moisture conditions. Results showed that with the increase of moisture content in a range of 10-22%, the thermal conductivity and specific heat of the plywood assembly enhanced significantly, and that plywood hot pressing noticeably consisted of fast heating and slow heating phases: during the first phase the heating rate of the core ply was quickened with the increase of moisture content while the second phase did not show any significant impact of moisture content on the corresponding heating rate.

As one of national important engineering, South-to- North Water Transfer middle line crossed the Beijing subway route 1. Various controlling technologies of deforming were applied during construction of water tunnel in order to control the deformation of the existing subway tunnel. At the same time, automatic monitoring technology was applied too. By the system analysis of monitoring data and controlling measures, the rule of structure deformation is concluded and the validity and fitness of controlling measures are validated. At last, it is useful experience for similar engineering.

The macroscopic static analysis of granule system performance in Literature [1] considered the position, direction and scale of the connection between granules in the system and other relevant physical properties. Taylor linear expansion was adopted to analyze the geometric displacement of the connection formed by granules. However, for the more complex granular connection in the form of network, the geometric position of granular connection in the statistical domain is linearly approximated, which may result in considerable calculation errors. In the complex network structure formed by granular connection, the displacement of connectors is discrete and discontinuous. In the presence of certain interactions among granular connections, there is the possibility to form spatial granular chain, with increased heterogeneity of deformation in the statistical domain. The accuracy of analysis will be affected if linear approximation is adopted. Shape parameter-based method proposed in this paper is a more universal method, which considers the influence of both the parameter of geometric location distribution of connectors and structural morphology of networks formed by granules. The core idea of this method is to introduce a corrected shape parameter vector for the non-linear part on the basis of linear approximation, to correct the displacement of connectors in geometric space so that the original linear analysis will better adapt to non-linear problems such as the network of connection formed by granules.

Tunnel geological environment has the characteristics such as complexity, uncertainty, variability and so on, How to improve the accuracy of tunnel geological advance forecast, guiding the safe construction of tunnel, are always as one of the hot topics on Geotechnical engineering study. This paper introduces the principles, methods and characteristics of a tunnel seismic prediction system (TSP24 system) that newly developed in China, through a successful application on highway tunnel geological forecast, which has verified the accuracy, reliability and economy of this system. The research results can provide reference for other similar projects..

Background reduction technique not only has the characteristics of pixels identify changes and small time complexity, but also can provide better detection results. The paper puts forward the running average method constructing background image by Gaussian mixture mode detecting background region and foreground region, and then adopting background reduction realizes the detection of moving target. Experimental results show that the algorithm effectively may realize background extraction and updating, and then completely and accurately detects moving targets. The algorithm has been achieved good results in the video vehicle detection.

The arm system is the central part in the design of a portable crane. The purpose of this program is to assure that the load moves approximately along the path of the horizontal direction in the process of luffing, through the optimization of the bars’ length of the arm system. Using vectors in the mathematical model, we figured out the coordinates of the bottom point of the truck-beam according to the geometric relationships of the four-bar linkage. With the appliance of proper algorithm and the idea of visualization, we calculated the reasonable length of the bars in MATLAB and transformed the results into software ultimately. The design is suitable for different types of portable cranes, and the software is very convenient and can be used in engineering.

2008 has seen the global financial crisis through which it is realized that a new growth mode, rather than Business as Usual, should be pursued in every country. Green New Deal, as a new economic growth mode, is generally accepted. Every country has increased the investment in green economy and made green economy a brand-new growth mode which resists economic and environmental crisis and promotes employment. Economy, environment and climates are the common problems all humans have to be faced with. Therefore, in the sense of Global Governance, Green New Deal shows a tendency to Global Green New Deal. Outstanding achievements have been made in China through the transformation of economic growth mode. Green Economy and Sustainable Development with Chinese characteristics have been gaining acceptance and approval by more and more countries.

In allusion to the compensation of environmental magnetic field for using three-axis magnetic sensor, a twelve-position calibrating method without north is designed. The equations of three-axis bias, scale factor error and install alignment error are deduced in the proposed method which is totally based on the magnetic field of up direction. According to the effect of hard iron and soft iron is equaled to the variation of three-axis bias, scale factor error and install alignment error, comparison experiments are completed in natural conditions and in conditions that the effect of hard iron and soft iron is artificially imposed. The experiment shows that this method can solve the compensation of hard iron and soft iron interference effectively for the application of up direction tumbling test.

There are more safety risks in subsea tunneling due to the particularity and complexity of its surroundings, so how to control the safety risks effectively has become an urgent problem. Based on the analysis of safety accident cases induced by the subsea tunneling, accident types and corresponding harms are pointed out. By analyzing the engineering characteristics and technical difficulties of the subsea tunnel systematically, the characteristics and occurring mechanism of the safety risk are revealed, and the fact that water inrush is the main safety risk in subsea tunneling is pointed out definitely. Furthermore, the contents of the safety risk control as well as relevant technical system are provided mainly based on water inrush risk, which can be referenced to make control schemes against the safety risk in subsea tunneling.

Electrical behaviors of light-emitting diodes (LEDs) prepared by wide-band GaN material were measured accurately using alternating-current (AC) small-signal together with anI-Vplot. An abnormal negative capacitance (NC) was observed in all measurend LEDs, and at the same voltage the lower the frequency is, the more obvious NC is. Form the slopes of ln(I)-Vplot and the relation between NC and voltage the ideality factor was approximately obtained.

Experiments of unloading confining pressure of rock were conducted to reveal deformation characteristics of rock mass under different excavation intension in thigh geostress condition. It were concluded from tests that volumetric strain of rock is inverse proportional to unloading rate. The smaller the unloading rate, the bigger the ductility of rock. Energy release are bigger under high unloading rate than that under low unloading rate. That means that tendency of rock burst turn smaller when unloading rates decrease.

Rock and soil aggregate (RSA) is a special geo-material and composed of hard matrix like gravel, cobble, pebble and soft matrix of soil. Discontinuity and heterogeneity are the main characteristics of RSA and its mechanical response is mainly controlled by its complex internal structure. The rock fragments play very important role in the mechanical performances under the condition of uniaxial compression and the rock content (the volume percent of rock fragments in RSA) of RSA is the focus of this study. RSA models with different rock content based on the structural characteristics were built for the numerical uniaxial test. The strength of RSA decreases instead with the increment of rock contents, stress-strain curves attained in the test reflect five different phases according to the deformation and failure process of samples.

According to requirements of the mechanical property, durability quality, working performance for patching materials for bridge and tunnel, the new patching material named high-performance tensile composite mortar (HTCM) has been developed. The HTCM is a product of cement-based mortar modified by polymer. The strength test, shrinkage test, chloride resistance test, carbonization resistance test and working performance test for HTCM are introduced in this paper. According to the test results, the components, characteristics, performance and operational principle of HTCM are listed in this paper. At last, the technical characteristics and advantages for HTCM are also discussed in terms of construction feasibility based on construction technology of sprayed mortar. It has been found that the HTCM can be used as an effective patching material for bridge and tunnel.

To remove casting porosity and obtain smaller crystal grains, many large forgings need ingots to be upset axially with large ratio of height to diameter (H/D) greater than 3. But the ingots with large H/D are prone to buckling during upsetting process, and have non-uniform internal stress and strain distribution, cracks at barreling and other defects. A new axial upsetting process was proposed to handle these problems. Firstly, the research described deformation inhomogeneity and cracking tendency, and analyzed the causes of defects in the flat anvil upsetting process. Secondly, three two-stage upsetting processes were tried to improve the uneven deformation in the flat anvil upsetting, which applied symmetrical spherical convex die, conical convex die and multi-line sweeping concave die respectively in the first stage, and used flat anvils in the second stage. The effect of the die surfaces on constraining those defects was analyzed. Finally, three three-stage upsetting processes were suggested to take advantages of different die surfaces to stabilize the process. It was observed that the upsetting had better result from using conical convex die and multi-line sweeping concave die in the first stage, conical convex die and flat anvil in the second stage, two flat anvils in the third stage. The new axial upsetting process could improve the quality of the large forgings with more uniform deformation and less barreling.

Activated alumina granules is a primary sorption media . The intention of this experiment is to get out of the difference between the different regenerate medias, caustic soda and alumina sulfate . Experimental result shows the renewal adsorption capacity of activated alumina using caustic soda regenerate is more than using aluminum sulfate .Under the same experiment condition ,aluminum sulfate can regain 13.27mg/g adsorption capacity while using 0.8 per cent caustic soda to regenerate alumina and 5.36mg/g using 4 per cent aluminum sulfate .The intensity of activated alumina granules reduces when we use caustic soda as regenerate media .The mass wastage of activated alumina granules is between 12% and 14% using caustic soda as regenerate media and between 6% and 8%uing aluminum sulfate .It is needed to neutralized by hydrochloric acid or aluminum sulfate after regenerated by caustic soda .Without neutralized, the concentration of treated water is over 1.0mg/l in the beginning.And neutralized with hydrochloric acid or aluminum sulfate, the efficacious run time can achieve 23 hours and 31hours .