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150 mm diameter 4H-SiC boules were grown by the physical vapor transport (PVT) method. Synchrotron white beam X-ray topography (SWBXT) was carried out to investigate the distribution of defects in axial slices cut from the boule. It was found that an increase of dislocations and micropipes was mainly induced by inclusions. After eliminating these inclusions, which were formed in the mid to late stage of the crystal growth, both the screw dislocation density and base plane dislocation density could be decreased down to a magnitude of 102 cm-2, which is comparable to that of high quality 100 mm diameter SiC substrates.

Artificial impermeable liner is the commonly used engineering technology method to prevent the Municipal Solid Waste (MSW) landfill leachate from polluting groundwater. The domestic and foreign researcher have discovered that the landfill impermeable liner was easy to have leaks during artificial liner laying down because of mechanical or the artificial mal-operation. The integrity test of impermeable liner for landfill began at the year of 2008. So a large number of historical landfill (construction completed before 2008) had become the pollution sources to local ecosystem because of the impermeable liner leakage. This article discussed the present situation of historical landfill leakage pollution, and propose technical and administrative measures to control those pollution in China.

High-quality 100 mm 4H-SiC boules were grown using the physical vapor transport (PVT) method with optimized growth parameters. Micro-Raman spectroscopy measurement shows that the 4H-SiC polytype of the entire wafer is uniform. The micropipe density is measured to be less than 1cm-2. The 1c threading screw dislocation (TSD) density can be suppressed to the magnitude of 102 cm-2. After chemical mechanical polishing (CMP), it is found that the warp of the substrate is less than 10 μm, and the surface roughness (Ra) is as low as 0.063 nm.

Office automation system provides enterprises with advanced office information processing means, immensely enhances office productivity and the quality of office, and enhances office management and decision automation and scientific levels. For the difficult problems in the development of office automation systems, this paper launched study for its framework. Firstly, it researches the fundamental framework composed by the user layer, service layer, application layer, the data support layer; then, researches the technical framework which uses Lotus Domino / Notes as the development platform and described its various components; Finally, researches the functional framework composed by the personal office, administration, document systems, public information, information systems, systems management and so on six large modules. Architecture technology provides a large number of software reuse, thereby improves development efficiency. OA system of developing using the contents of this paper has advantage of a clear structure, stable performance, easy to maintain, easy to transplant and so on.

Experimental study on macroscopic spray characteristics of a certain type of domestic common rail injectors under the conditions of different injection pressures was carried out through a high-speed digital camera. Furthermore, a fuel dripping phenomenon at the end stage of injection was observed through the high-speed digital camera equipped with a long-distance microscope, and a further analysis of the phenomenon was made. The results show the increase in the injection pressure can evidently enhance spray cone angle and expand the scope of spray field in combustion chamber, which is conducive to air-fuel mixture. The spray cone angle during the development spray shows a double-peak shape. And the long response-time of seating of solenoid valve core that disables the injection cutting off in time is one of factors causing fuel dripping phenomenon.

Three principal components (cellulose, lignin, and hemicellulose) of coconut shell (CS), an abundant tropical biomass, were quantified using the Van Soest method. It was observed that CS had a high content of hemicellulose (30% of the raw CS material). The present study was undertaken to investigate the extractability of hemicellulose from CS obtained by ultrasound-assisted potassium hydroxide solution with the hydrogen peroxide method. The ultrasonic treatment and sequential extractions with alkali and alkaline peroxide under optimal conditions led to a release of more than 93% of the original hemicellulose. The effects of experimental variables, including pH value, reaction temperature and time, hydrogen peroxide content, and magnesium sulfate dosage on hemicellulose content were investigated. The obtained hemicelluloses were characterized by Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), and comprehensive thermal analysis (TGA), which showed that potassium hydroxide significantly affected the yield of relatively pure hemicellulose.

Based on the high speed camera combined with a microscopic lens the near-nozzle spray surface structure and flow characteristics of the high pressure diesel fuel jet were investigated. During the steady period of the spray development, the periodically undulatory structure was observed at the circular direction of the jet at the near nozzle area at the injection pressure of 5MPa. The atomization of the spray improved and the periodical structure was veiled by fine droplets at higher injection pressure of 40MPa. During the closing period of the nozzle lift, the spiraling shape was also observed along the surface of the fuel jet which indicates the internal helical flow characteristic.

Road detection is a primary problem for autonomous vehicle. There have been many approaches attempting to solve this problem. However, most of the approaches tend to be affected by shadow, occlusion and not always robust. In this paper, we propose a new approach to detect the road boundary, our approach has two parts: firstly, we detect the road boundary by random forests on the pixel level, then we track the road boundary by particle filter with the parameters of vanish point position and road boundary slope. The experiment shows our approach is an effective way to detect road boundary fast and robustly.

Research on reliability of distribution network has very important meaning and function to ensure the quality of power supply. This paper introduces some basic concepts of reliability in distribution network, including distribution network reliability definition, task and index. The classical reliability evaluation method was reviewed, and focused on specific distribution network, an example analysis was given, and specific reliability evaluation indexes were calculated. Finally, the future development of distribution network reliability evaluation was made a simple prospect.

The parallel capacitors are the most important reactive power compensation devices in power system, while the power system harmonic pollution is becoming increasingly serious in recent years, the accident that caused capacitors fault and damage by overload harmonic always happened. Based on this background and summary of the existing research results, thermal effect and performance index of capacitors are introduced, and analyzed the mechanism of interaction between harmonic and capacitor, then the effect and harm of running capacitor under harmonic conditions are elaborated, finally summarized the feasible measures for harmonic suppression and protection of capacitor devices.

Natural gas is one of the cleanest and hydrogen-richest energy among all the hydrocarbon energy sources. This paper expects to examine the causal relationship of economic growth with natural gas consumption, sustainable development, and social development. Natural gas is the most principal urban gas source in China. In addition, shale gas has become a new major alternative resource for satisfying the rapidly increasing demand for energy since 2012. Then, the importance of examining the relationship among economic development, natural gas consumption and environmental performance index is obvious and urgent.

Active control of turbine blade tip clearance continues to be a concern in design and control of gas turbines. Ever increasing demands for improved efficiency and higher operating temperatures require more stringent tolerances on turbine tip clearance. In this paper, a turbine tip clearance control apparatus and a model of turbine tip clearance are proposed. The active clearance control (ACC) of aero-engine turbine tip clearance is evaluated in a lapse-rate take-off transient, along with the comparative and quantitative analysis. The results show that the resultant active tip clearance control system has favorable steady-state and dynamic performance and benefits of increased efficiency, reduced specific fuel consumption, and additional service life.

The roots compressor is a kind of rotary compressors, it is applied widely in mechanical engineering, chemical industry, aerospace industry and other fields with its high speed, long life and mechanical efficiency. In the article, a new combination rotor profile curve of the roots compressor was designed by reviewing the relevant literatures, the 2D finite element modal was established and a transient CFD numerical simulation was performed for a roots compressor by means of dynamic mesh technique. The varying tendency of mass flow rate, the velocity vector and static pressure distribution of the roots compressor were obtained and analyzed.

The dynamic model is obtained based on researching the structure of single inverted pendulum system in this paper. Mathematical model of inverted pendulum that is close to the working point is deduced by linearization. A PID control algorithm is put forward by analyzing the factor of influencing inverted pendulum stability. The effectiveness of proposed algorithm is verified by simulation. This algorithm has the features of high control precision and good stability.

The assessment of risk of default on credit is important for financial institutions. Logistic regression and discriminant analysis are techniques traditionally used in credit rating for determining likelihood to default based on consumer application and credit reference agency data. We test support vector machines (SVM) against these traditional methods on a large credit card database. We find that they are competitive and can be used as the basis of a feature selection method to discover those features that are most significant in determining risk of default.

Services composing have played an important role in the industry and academia in recent years. Based on the relevant theory and experience of the shortest path problem in a DAG, we propose the method of dijkstra algorithm implementing services composing way selection. Then we provide the pseudo code description of the algorithm implementing the optimal path selecting process and test the correctness of algorithm through the contrast experiment to offer a feasible solution for services composing way selection.

Shadow is one of the important issues in building integrated photovoltaics (PV) design stage with which must be faced. If it is not solved well, it would seriously affect the energy yield of the system and the project benefits. This paper, based on Beijing-Shanghai high speed railway Nanjing south station PV demonstration project, gives the visualization analysis of shadows in annual regional shadow as well as the maximum amount of solar radiation. The research and application of optimizing the system efficiency will drive the development of building integrated PV and promote building energy efficiency and emission reduction.

Based on the statistical pattern recognition theory, the AMRA timing analysis methods are used in the article, through the combination of long autoregressive model residuals method and the least squares method the model parameters are estimated, and a system model is established. By using mean control chart method the vibration information and feature of the pressure pipe are extracted and selected, so whether the pressure pipes is damaged can be judged effectively. The simulation results show that structural abnormalities test method of the mean value ,which is Based on the recognition theory of statistical pattern, can accurately diagnose structural damage detection state ,the injury degree and damage location, it has a very strong sensitivity

This paper considers the nolinear system robust estimation problem with measurement time delay. The purpose is to provide algorithm for inertial navigation system nonlinear error model in transmittion delay case. Considering that innovation regroup method can treat the measurement delay problem better with no addition of system state dimension, and decrease the system computation, therefore, that algorithm is combined with extended set-membership estimation and deduce the distrete nonlinear system extended set-membership estimation algorithm with measurement delay, realize nonlinear system varying state estimation and the treatment of measurement delay. At last, apply the algorithm to carrier aircraft in-flight alignment and validate the effecitiveness.

The corrosion resistance layers can be surfaced in the valve casted by carbon steel, to enhance the corrosion resistance performance. By the 3D solid model, the weight and internal area of valve body was obtained. The surfacing process was designed and the welding rods theory amount was calculated. And the actual amount was close to the theory one. The surfacing and cutting process was designed for the fit surfaces and the dimension chain was calculated to meet the fit accuracy and the corrosion resistance layer thickness. The results show that it has the engineering significance by using 3D solid model to estimate the producing costs; the fit accuracy and the corrosion resistance layer thickness can be obtained together based on the surfacing and cutting process; in this way, the cost can be cut down more than 30%, compared the whole stainless steel valve.

University scientific research management platform for the scientific management research personnel to carry out the work to provide convenience, for the leadership decision-making to provide auxiliary support, for teachers to carry out research activities to provide services. This paper studies the basic work of building university scientific research management platform. For the problem that the function is difficult to determine, it researches functional framework composed of scientific research information, scientific research results, scientific research projects, scientific research statistics, portals, system management and others subsystem; For the problem that the software development is difficult to achieve, it based on B / S structure to research three layers framework structure consisted of the user presentation layer, business logic, data access layer, and to describe each layer. Using the contents of this paper to build scientific research management platform, for the standard software development methods and improving the efficiency of system development has great significance.

To the situation of hardness of Mybatis pagination, propose an interceptor based general physical pagination component. The component is designed by MVC(model-view-controller). Controller is realized using annotation based controller of Spring MVC. To design the business logic layer core method into general, DAO method custom and generic model was introduced. Interceptor was introduced into data persistence layer to realize physical pagination. JSP is used in page displaying. Give the detailed realization process of the component. Application results show that the proposed component has good generalization and portability, high execution efficiency and better flexibility.

Risk-based method has been increasingly frequently used by regulators and managers in modern landfill to scientifically manage solid waste and reduce its environmental hazards. As far as hazardous waste landfill is concerned, the main risk can be identified as the leakage of leachate. To quantify the uncertainties and its influences on risk assessment of leachate leakage, EPACMTP model with the involvement of Monte Carlo method is used to propagate the randomness of input parameters; Fault tree analysis method is employed to compute the uncertainties of liner damage; and the last, health risk assessment model was also integrated into to form a holistic model of leakage risk assessment.. A hazards waste landfill located in the southwest China is taken as a case study. The assessment result indicates that 1) the main exposure pathway is oral intake;2) The total non-carcinogenic risks for adult and for child are, accordingly, equal to 0.68 and 0.75, which under most circumstance is acceptable.

A major role of automotive engineers is to improve fuel efficiency and vehicle safety. However, it is very difficult to improve both of these requirements at the same time. So they deal with the design of structural reinforcements in hopes to improve the crush strength, but minimize the weight of the automobile body. Forming simulation has been playing increasingly important role in this field to save time and cost and the accuracy of the simulation argued against the real life results. In this paper The Auto Center pillar reinforce plate is studied by finite element method, and forming process is optimized according to full flow simulation. The simulation shows that the FEM can make the tryout process better to get high success rate and shorter time.

Landfill liner leakage detection has become the necessity procedure before the landfill put into operation. The dipole detection technology is studied and which can find the leaks of liner without any destruction of liner. This article discusses the key factors affecting the dipole sensitivity including the resistivity and thickness of the medium above the liner, and the distance between the dipole and the liner, the dipole spacing. The results indicate that higher resistivity of the medium, the thinner the liner is. Based on which the dipole method device is developed. Almost 68 landfill liner leakage detection surveys had been done recently in China using dipole technology. The results show that every landfill detected has leaks in liner, and the leaks detected per hectare is about 22 unit and 24 unit per landfill. Dipole technology has become the primary method in landfill liner leakage detection and play the critical role in landfill liner construction quality supervision.

With the rapid development of economy and the improvement of human life, intensified the contradiction between human, environment and water.Residents in villages and towns in our province has water the consciousness of legal system and the present situation of water environment related local research data through to our province visits,interviews, and the data was analysed, the association between the ruralwater environment problems and the residents water law consciousness,and putting forward proposals and strengthen the residents waterconsciousness opinion, for reference reference.

Shale gas holds great promise for a countrys economic development and energy independence, but also holds potential perils for the natural resources and the communities. Following the shale gas revolution in the US, China is in full swing to deploy its strategic plan for the shale gas. The Ministry of Land and Resources (MLR) has announced the legal status of shale gas as the 172th independent mining resource, and hosted two rounds of bidding for the commercial development of 23 shale gas blocks. The shale gas revolution seems to may happen in China as well. However, some great challenges exist during the shale gas extraction. One is the impact on water resources for shale gas production, unlike the US, water shortage has been a severe problem in China, hindering its economic development. The other one is that shale gas operations may induce environmental problems, such as accidental spills of flowback water, which contains toxic substances. Spills could have long-term cumulative effects on ecosystems, as with oil spills. This paper highlighted water resources challenges and policy vacuum facing in China. Although the U.S. shale gas experience can assist in identifying some potential issues that Chinese regulators and operators may encounter, policy decision on this issue should be based on risk assessment and regulation studies. For China, there is a long way to lay the groundwork for the shale gas revolution.

The study of solid-state composite polymer electrolyte (CPE) using different synthesis technique and test methods is a hot spot of current topics in polymer materials science. The electrolyte is a multiphase material with the advantageous properties over different dropping fillers. This manuscript presents a new idea for preparation composite polymer electrolyte based on the poly (ethylene oxide). We use scanning electron microscopy (SEM), Differential scanning calorimeter (DSC) measurements etc. to character the polymer electrolyte and their properties. This paper contains some new results. We observed a very change improvement of ion surface morphology by adding appropriate content of dropping fillers.

There is a remarkable friction between drill string and borehole in extended-reach wells and horizontal wells due to large deviation angle, contact between drill string and borehole, non-rotation of drill string. The large friction and torque will induce blocked bit weight, low ROP, constrained drill string extension. This article summarizes the common used antifriction methods and tools in extended-reach wells, focusing on Non-Rotation Drill Pipe Protector (NRDPP), roller antifriction tools and vibration antifriction tools. The working principle, structure design, performance and field application of which are introduced. With the increasing numbering of complex structure wells which include extended-reach well and horizontal well, antifriction technology has broad prospects for development.

In this paper, a new kind of recursive algorithm has been raised. It optimized the distribution network system reliability calculations, improved some efficiency, and met the user's needs closely. This algorithm needs no network equivalence process,has no complex principle and brings no difficulty to programming.Through its failure analysis, can be more easily identify key equipment of distribution systems for customers to adjust. This algorithm can easily cooperate with fault reconfiguration.No adjacency matrix and special chain table will be formed during searching procedure; it takes advantage of basic table of node data and branch data to do searching work, and easily to get access with field data. The algorithm uses recursive search also reduces programming greatly.

The influence of pH onMonoraphidiumsp. FXY-10 growth, lipid content, lipid yield, biomass yield, and fatty acid composition is studied in autotrophic and heterotrophic conditions. The results reveal thatMonoraphidiumsp. FXY-10 can grow better in an acidic environment. Under autotrophic and heterotrophic conditions, the culture time is 37 and 9 day, respectively. And the maximum biomass of algal cells is 32 and 367mg/l/d with the lipid content in autotrophic and heterotrophic conditions reached to 49% and 39%, respectively, with high biomass yield, lipid yield, the saturated fatty acid and monounsaturated fatty acid under heterotrophic condition, proving that the algal cells are a viable material for the production of biodiesel.

Taking the concrete face cock-fill dam upper reservoir of Tianchi as an example, the stress and deformation characteristics of concrete face rock-fill dam are studied in-depth in this paper. The article builds a fine three-dimensional finite element model of Tianchi upper reservoir by a nonlinear elastic model of the finite element software ADINA. The stress and deformation of the two conditions under completion and storage for the dam are calculated ,which will be analyzed to obtain stress - strain distribution of the dam in two conditions, comparing dam stress and deformation before and after impoundment to get impact of the water pressure on the dam stress and deformation: comparing after impoundment and completion , the dam water level displacement of upstream side from role of horizontal water pressure will increase , the dam upstream offsets to downstream , but the offset is little ; Due to dam is affected by vertical hydrostatic pressure and uplift pressure after impoundment , the dam settlement is slightly less than the completion in storage. KEY WORDS: Tianchi upper reservoir, The concrete face cock-fill dam, Three-dimensional finite element, Nonlinear elastic model, Analysis of stress and deformation

Ganoderic acid R (GA-R) possessed significant cytotoxicity on a multidrug resistance (MDR) tumor cell line (KB-A-1/Dox) and a sensitive tumor cell line (KB-A-1). The results indicated that the inhibition effect of the GA-R was due to the induction of apoptosis. The use of GA-R in vitro resulted in a restoration response of the KB-A-1/Dox cells to the anti-tumor drug doxorubicin by stimulating the drug accumulation within the cells. The index of MDR reversion of GA-R was about 22 folds. The findings show that the ganoderma triterpene may be good candidates for anti-tumor and anti MDR chemotherapy.

This paper considers material nonlinearity and geometric nonlinearity,study in-depth the force performance using the finite element method for space curved steel box girder bridge, through the six series of 20 specimens calculation and analysis, simulation different local structures curved steel box girder bridges reflect more accurately the role of various factors in the mechanical behavior. This in-depth analysis of the different local structures in space curved steel box girder bridge performance, for guiding the engineering design has a certain reference value for further study curved steel linear and nonlinear mechanical properties and stability lay a good foundation.

Histogram equalization (HE) algorithm is wildly used method in image processing of contrast adjustment using images histogram. This method is useful in images with backgrounds and foreground that are both bright or both dark. But the performance of HE is not satisfactory to images with backgrounds and foregrounds that are both bright or both dark. To deal with the above problem, [ gives an improved histogram equalization algorithm named self-adaptive image histogram equalization (SIHE) algorithm. Its main idea is to extend the gray level of the image which firstly be processed by the classical histogram equalization algorithm. This paper gives detailed introduction to SIHE and analyzes the shortage of it, then give an improved version of SIHE named ISIHE, finally do experiments to show the performance of our algorithm.

For a B/S based registration system, online photos collection is an important but difficult task, Because there are strict requirements of format that photos have to meet and the management of photos is complicated and likely to be in chaos if there is no good photo storage strategy. To solve those problems above, this paper presented an online photos collection component which contains two solutions: online-cam and local photo upload to allow candidates to submit photo online by themselves. First, it analyzed the principle and design process of flash based online-cam in detail, and then illustrated the implementation of both solutions proposed above. This component has already been used in several registration systems, and effectively simplifies staffs work and improves the quality of photos.

Related Vehicle Routing Problem is another form of Vehicle Routing Problem. RVRP also belongs to NP-Hard with a wide range of application areas and major economic value. The research based on single distribution center RVRP with road capacity static constraint, to build a model of single distribution RVRP and propose a kind of chaos genetic algorithm to solve this problem, with experiments verify the feasibility and effectiveness of the algorithm.

The research based on complex RVRP. On the basis of deep analysis, a parallel genetic algorithm was designed. Simulation results proved that the parallel genetic algorithm is more excellent than conventional serial genetic algorithm.

Study the basic theory and process of chaos particle swarm optimization (PSO) algorithm, improve the basic PSO algorithm by introducing the self-adaptive inertia weighting factor method. Construct the mathematical model of basic logistics scheduling to complete the simulation analysis experiments. Experiment results show that self-adaptive chaos particle swarm optimization algorithm is effective and feasible to solve the logistics scheduling model problem.

For investigating the effect of ultrasonic treatment on the cooling and lubricating action of cutting fluid, an ultrasonic treatment system of emulsion fluid was developed to be used in cutting experiments. And the comparison experiments were carried out with YT15 tool turning 45 steel, under the conditions of dry cutting, fluid and ultrasonic treatment fluid. The results show that as ultrasonic treatment one used cutting forces decrease about 10%-15% and 5%-10% to dry cutting and fluid; the cutting deformation coefficients reduce too; and the machined surfaces are enhanced. Therefore, the cooling and lubricating performances of the fluid are improved by ultrasonic treatment. As a result, the using quantity of emulsion fluid would reduce indirectly, and this help to energy saving and emission reducing.

Land resource is an important part of environmental resources. In order to make better use of limited land resources, we should strengthen the evaluation of sustainable utilization of land resources. Firstly, This paper constructs land resource sustainable utilization evaluation index system of primary from two angles of quantity and quality . Secondly, we uses the AHP method to filter the index. Finally, we constructs the sustainable use of land resources final evaluation index system .

The beef flavor was selected to carry out toxicological analysis regarding food intake, body weight, organs weight and blood biochemical indexes in mice. The results show that beef flavor could suppress food intake but promote mice weight compared with the control group. Flavor intake has significant effect on the ratio of liver and lung weight to the whole body weight, but it has no difference in the ratio of heart, spleen and kidney weight. Some biochemical indexes about fat metabolism in blood such as the total protein, total bile acid and alkaline phosphatase are respectively 4 g/L, 0.7μmol/L and 23 IU/L more than the control group. These factors and cholesterol, triglyceride, low density lipoprotein, high-density lipoprotein cholesterol in the mice blood all have extremely significant differences (P

In this paper, the compound shellac fruit wax was prepared by SiO2 aerogel, shellac, sodium hydroxide, fungicide. The obtained fruit wax was used to preserve the mango in tropical area. The results show that the compound shellac fruit wax with 0.2% SiO2 aerogel can suppresses water loss, adjust the respiration, reduce the rot rate, thus extending the preservation time of mango.

t is high in efficiency to cut rectangular steel pipes with flame cutting mode compared with milling mode, and it is simple in processing equipment. When cutting the four arc angles of steel pipe, the steel pipe carries out the uniform rotational motion while cutting torch carries out plane two-dimensional motion, in order to achieve uniform motion in a straight line relative to the round arc angle of steel pipe. The rotation speed of steel pipe is proportional to the cutting speed. And the X component and Z component for the speed of cutting torch will respectively change according to the sine and cosine curves. The space geometrical relationship and motion relationship of round corner torch track and steel pipe corner are described by means of parametric equations. And the correctness of the algorithm in CNC rectangle pipe cutting machine has been verified.

Chitosan modified by microwave irradiation were used for hexavalent chromium removal from aqueous solutions. Sorption parameters including pH, temperature, initial concentration and contact time have been investigated. The maximum sorption of Cr (VI) on modified chitosan occurs at pH 5,whereas the sorption capacities of modified chitosan were significant over pH 2 to 7. The results obtained from equilibrium sorption studies are fitted in various sorption models such as Langmuir and Freundlich and the model parameters have been evaluated. Maximum sorption capacity of was 147mg/g at 15°C. Kinetic models including Lagergren first-order and second-order were used to test kinetic data. The results showed that second-order has good agreement with experimental data. Thermodynamic parameters of the process were also. Thermodynamic parameters including free energy (DGo), entropy (DSo) and enthalpy (DHo) of sorption were also investigated at different temperatures. The negative values of Gibbs free energy and enthalpy changes for Cr (VI) indicated the spontaneous and exothermic nature of the sorption process.

This paper introduces the Changes in agricultural production of Hebei Province from 1949 to 2011,firstly.Then We analyzed the factors that influence the sustainable development of Agriculture.Finally, we put forward some development proposals.We hope to have reference to the other provinces of the sustainable development of agriculture .

The use of MODIS remote sensing data desired physical concept fuel preheating energy based on data, by fully considering the heat in the ignition probability index actual transfer heat loss in the process of combining fire probability index by population density and surface roughness index. Construction of integrated fire danger index by ignite two exponential probability index and fire probability index. After the analysis of forest fire in Heilongjiang in October 12, 2004 fire points results, show that the model can obtain better forecasting results. This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.

A type of bogie structure was proposed for the eight-axle locomotive, of which the middel bogie forme was used to connect the two B0 bogie and support the car body with three suspensions. A single drawbar connect the B0 bogie and car body directly to transfer the longitudinal forces. This structure is simple and feasibility, which can achieve high adhesion availabillity and good dynamic performances. Three suspension can achieve a excellent stability of car body. Comparing with a same speed and axle load class 2C0 locomotive, the wheelset lateral force and wheel rim wear factor are reduced by about 35% at the R300m small radius curves, and the wheelset lateral force is decreased by 15%, and the rim wear factor is reduced by 23% at the R800m curves.

A kind of small molecular hemicellulose was prepared from coconut shell by ultrasound-assisted and alkaline hydrogen peroxide extraction. Unlike the common hemicelluloses and celluloses, it is similar to liquid for the hemicelluloses in ethanol solution, but insoluble in it. Through the gel permeation chromatography (GPC) analysis, it was found that its molecular weight is much lower than that of the traditional hemicelluloses, indicting the lower polymerization degree. But from the infrared spectroscopy spectra analysis, this type of small molecular hemicelluloses has the similar infrared spectrum characteristic peaks to that hemicellulose.

In this work, B4C porous ceramics reinforced alumium composite was fabricated by the sponge impregnant method and pressureless infiltration technique. The wettability of aluminum on B4C, the component and the wear resistance of the composite were studied .The result indicates that the infiltration temperature is determined 1200 centigrade and there are mainly Al, B4C, Al3BC , no AL4C3in the experimental composite, the wear resistance of B4C/AL composite is 25 to 30 times higher than that of the alumium.