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In this study, one novel WC/Ni flexible cloth coatings were prepared to enhance the abrasion and erosion resistances and meanwhile to accommodate the complicated component surfaces. Neither precipitation of WC particle nor pores or cracks were detected in the coating. The scarification extent of WC particle decreased with the increase in the WC content. With the abrasion mechanism of three body abrasive wear, the WC/Ni coating with 59.8 wt.% WC (WC/Ni-59.8 wt.%) showed the best abrasion resistance with the wear rate of 0.3% of 304 stainless steel. At 30° of impact angle, the WC/Ni-59.8 wt. % exhibited a superior erosion resistance to that of WC coating developed by high velocity oxygen fuel (HVOF). The application potential of WC/Ni flexible cloth coating for the commercial components was testified by developing the coating on a ball valve disc.

The cone tube is an important part of the circuit connector, which has high requirements for its forming quality. In this paper, the cone tube is taken as the object, the finite element model is established, the radial forging process of the cone tube is simulated, the influence of process parameters such as axial feed and friction on the thickness of the cone tube is studied, and the influence law is analyzed, which has certain reference value for the analysis of the forming law of the radial forging.

In this paper, the optimization of the parameters of the isothermal forging technology to form spur bevel gear was studied. The goal of the optimization is to decrease the forming load during the process. Then, some factors included the ratio of height to diameter of billet, thickness and position of punching recess, deformation temperature and velocity were taken as the optimization values and the orthogonal experimental method was employed to carried out the optimization. After the optimization, a set of optimum technology parameters were obtained. The result demonstrates that the precise spur bevel gear can be formed with less forming load and without causing under-filling and folding defect by using the isothermal forging and choosing suitable parameter, which provides reference to form the spur bevel gear.

For the forging with complex shape, the preform design is a difficult problem in the process and die design. It has an enormous influence on the quality of the forging. In this paper, combining with the FEM, the Ant Colony Algorithm was used for the preform optimization design. The general Ant Colony Algorithm was improved to fit for the multivariate continuous function optimization. The preform die shape was represented by B-spline and the coordinates of the control point of the B-spline were taken as the optimization design variables. The optimization program was developed. Finally, aimed to decrease the material cost of the forging, the preform optimization of a typical H-section forging was obtained using the self-developed program. The optimization results show that the improved Ant Colony Algorithm is suitable for the preform optimization design of forging.

Hydroforming has been used widely across many industrial fields. Large applied pressure during hydroforming makes it necessary to consider the influence of normal stress in the thickness direction, while in FE simulation, the use of traditional shell element based upon plane-stress assumption is not appropriate in such cases. Here, the traditional shell element is modified by changing the constitutive relation which took into account the normal stress in the thickness direction, and the modified shell element formula is combined with Yld91 yield function to simulate the forming process of Aluminium alloy. Then the element formulation and material model is implemented into the FE code Ls-Dyna by means of USER interface. Two examples are carried out and good correlations are obtained when compared to the traditional shell element and solid element.

By using the potential theory and the superposition principle, Productivity model of multi-fracturing horizontal well is established under the condition of infinite conductivity fractures. It solves the problem by using numerical methods and analyzes the influence of fracture numbers, fracture length and fracture spacing on well production by using actual reservoir parameters. Finally, it analyzes the production decline characteristics of multi-fracturing horizontal well based on the change of production curve. In the early period of production, the well production increases with the increase of fracture numbers, fracture length and fracture spacing. In the late period, the fracture parameters have less effect on well production. Early-stage production of multi-fracturing horizontal well obeys to the modified-hyperbolic decline model, while the relationship between ratio of Q, Qi and time is exponential model in the late-stage. It has some significance for design of horizontal well fracturing parameters and production forecasts in unconventional reservoirs.

For the relationship of environmental parameters and variables in the each transport process, by using data mining, the system gets the corresponding decision tree. In a certain environment parameters conditions, the occurrence of the event is determined by the decision tree. Through the No Free Lunch Theorem (NFL) revelation, the original PSO algorithm is improved to enhance the validity of the original decision tree. To the final experiments results, once again demonstrate the improved algorithm is efficient.

In turbine engines, Ni or Co based alloys are used at high temperature, either as base materials, superalloys, or deposited on the surface of superalloys, as coatings. In the present study, two different MCrAlY overlay coatings, Ni and Co based, on a Ni based superalloy IN792 were aged for different times in air at three temperatures, 900°C, 1000°C and 1100°C. The aging processes were simulated by using DICTRA software by focusing on the interdiffusion behavior in the superalloy-coating systems. The results of simulation captured the main microstructural features observed and were used to analyze the diffusion behavior of alloying elements and the corresponding microstructure development. It was found that coating composition and temperature affected significantly the microstructure near the superalloy-coating interface, and their relations were mapped as a summary.

BoVW (Bag of Visual Words) Model has attracted much attention for many computer vision applications in which an image is represented by a histogram of visual words. Two of its critical steps are to construct a visual dictionary and to quantize each local feature to its nearest visual word in the dictionary. In this paper, we present the framework of a generalized BoVW (GBoVW) Model in which feature quantization can be replaced by sparse coding based feature encoding. We also propose to use spectral clustering to construct a visual dictionary to overcome the shortcomings of K-Means based clustering algorithms. Image retrieval experiments on ZuBud database indicate that GBoVW Model improves BoVW Model and the visual dictionary generated by spectral clustering achieves better performance than that by K-Means based clustering methods.

Waste ceramic tiles are broken into sandy gravel to configure reclaimed sand instead of part of normal sand. Bending strength tests and compressive strength tests of mortar samples were carried out under different substitution rate of ceramic tile wastes sand in different curing time, which the ratio of cement and the consistency of mixture were fixed. The results indicate that strength grade of masonry mortar recycled by ceramic tile wastes under different substitution rates can be improved 1 or 2 grades, and the strength linearly increases as the curing time increases under the same substitution rate, and the growth rates of bending strength and compressive strength are inconsistent.

The sewage diffusion is an environmental material for protecting marine environment. It plays an important role in port engineering. Its effect under deep water was carried out between different diffuser design parameters based on the hydraulic model test, and Cao Fei-dian SCIP sewage marine disposal project was taken as an example. For this project, jet angle was controlled to be 0 degree, and horizontal angle was controlled to be 0 degree. It not only can ensure that sewage fully diluted mixed, also can avoid the premature convergence and sewage lifting. It is feasible for selecting large angle nozzle under deep water and there are some technical bases have been provided for other sewage marine disposal project.

For analyzing initial moisture content of corn stalks, feed rate, airflow temperature and airflow velocity which affect drying, the experiment bench of air drying was established, industrial analysis, single factor and multi-factors orthogonal experiments for corn stalks were done. The drying curves about various factors were summed up to conclude airflow temperature is the most important factor which affects drying effect.

Computational Fluid Dynamics (CFD) simulation often needs to periodically output the intermediate results to files in the form of snapshots for visualization or restart, which seriously impacts the performance. Traditional CFD simulation takes ASCII format with typesetting in the snapshot output process, which results in precision loss of the data in the snapshot array and more storage space occupancy than the original binary format. In this paper, we propose the binary non-typesetting format optimization for the snapshot output in CFD simulation, aiming at eliminating the impact of ASCII format. In our optimization method, the snapshot array is output in binary format without typesetting. On one hand, it reserves the original binary precision in the output files, while the ASCII format always has precision loss, which seriously impacts the accuracy of CFD simulation; On the other hand, non-typesetting provide the opportunity of output the snapshot as a continuous memory block, which will signally improve the efficiency of the output. We design the multiply output mode framework for CFD applications through the combination of ASCII typesetting format and binary non-typesetting format. We implement this multiply output mode framework in the open source CFD software OpenFOAM. Experimental results on Tianhe-2 supercomputer demonstrate that our binary non-typesetting format optimization technique can achieve good optimization effect for the periodical snapshot output in CFD application.

In order to explore the reaction mechanism of preparing SnO2/C composite materials by biotemplating, multiple samples are prepared by carbothermal-reduction under vacuum from ramie fibers/Sn (OH)4 precursors, which were prepared from ramie fibers impregnated with Sn (OH)4 sol. Thermodynamic calculation and experimental research indicate the reaction mechanism of preparing SnO2/C composite materials is that granular SnO2 is generated by pyrolysis of Sn (OH)4 at about 345.7°C,which distributes in the clearance of the ramie carbon. Pellet-like SnO/SnO2 composites generated by gas-solid and solid-solid reaction is solid solution of SnO and SnO2 in the Sn-O-C-H reaction system. And the microstructure of the composites changes from block to pellet-like with the increase of Sn content. The results show that the temperature of 631.3°C is the critical temperature that the reduction reaction of SnO2 and C can occur spontaneously. With the increase of sintering temperature, SnO2 is reduced to SnO and Sn by agent C and CO, SnO2 in turn. Furthermore, thermodynamic analysis results coincide well with the experiment data.

Accurate rebar recognition is a key step of automatic online rebar counting based on image processing. Current popular rebar recognition methods based on front view image usually lead to missing detection for some special rebar such as obscured rebar, oxidation dark rebar and bent rebar. So a novel rebar recognition method based on multi-view images was proposed in this paper. Firstly, rebar images were captured simultaneously from front view and top view using two cameras. Then, the centers of rebar were located respectively in top and front view image. Finally, in the image fusion step, the top recognition result was used to compensate and validate the front recognition result for reducing and eliminating above missing detection. Experiments showed that this method can efficiently recognize above missed rebar and improve rebar recognition rate.

The sewage diffusion effect under deep water was carried out between different diffuser design parameters based on the hydraulic model test, and Huizhou Dayawan sewage marine disposal project was taken as an example. The experimental results show that the design parameters are significant for sewage diffusion at the near field. For Dayawan project, jet angle was controlled to be 20 degree, and horizontal angle was controlled to be 90 degree. It not only can ensure that sewage fully diluted mixed, also can avoid the premature convergence and sewage lifting. It is feasible for selecting large angle nozzle under deep water and there are some technical bases have been provided for other sewage marine disposal project.

The construction noise and wasted material of total precast concrete structure are reduced by factory production of components and assembled construction, green construction can be achieved.Combined with the first total precast parking structure in China, the connection modes of precast components are introduced,such as between precast columns and precast columns, between precast columns and precast inverted beams, between precast double tee slabs and precast columns or precast shear wall, which can provide a reference for the design of similar engineering.

The sewage diffusion is an environmental material for protecting marine environment. It plays an important role in port engineering. Its effect under deep water was carried out between different diffuser design parameters based on the hydraulic model test, and YangKou sewage marine disposal project was taken as an example. For YangKou project, jet angle was controlled to be 0 degree, and horizontal angle was controlled to be 0 degree. It not only can ensure that sewage fully diluted mixed, also can avoid the premature convergence and sewage lifting. It is feasible for selecting large angle nozzle under deep water and there are some technical bases have been provided for other sewage marine disposal project.

In this paper we proposed an improved watershed algorithm for the quasi-circle overlapping images of the bars end face. According to the classical watershed algorithm, which often causes over-segmentation, the improved algorithm does a series of pretreatment with the original image, such as sobel filter. With the gradient operator and mathematical morphology method, we firstly obtain the smooth image of the forced local maximum marks. Then, on the basis of the quasi-circle characteristic of the target image, we proceed to maximize the erosion with circular structure in order to prevent under-segmentation. Finally, we use the watershed algorithm to segment the gray image based on distance transform. So we can separate the target from each other to achieve the accurate counting purpose. By using the proposed algorithm in the article, we obtain satisfactory segmentation results of the quasi-circle overlapping image of the bars end face image.

Retrofitting and reinforcement project of a historic hotel building are introduced in article. The method of increasing new concrete frame structure in original structure interior and the original exterior wall considered as a retaining structure was adopted in the retrofitting and reinforcement project. The structure subjecting to the force was clear and the reinforcement construction process was relatively simple after the retrofitting and reinforcement. Design and construction of the structure strengthened are according to the existing code completely and can ensure the safety and the seismic performance of the structure.

The snow load of a space truss structure subjecting is unevenly distributed after snowstorm disaster, which caused uneven forcing and local damage of the members and roof purlin of the original space truss. The damaged members and roof purlins were strengthened and replaced in loaded condition in order to guarantee the space grid structural safety. The results during the construction process have shown that the presented strengthening plan is successful, which can provide us a good reference of the similar projection.

The reinforcement project is three-storey of the industries building, the total height of the industries building is 14,200mm, the clear height of one storey is 7,500mm, the building area is 1,500 square meters, structural mode is reinforced concrete frame structure. The structural members were damaged seriously due to fire In January 2010, strengthening the damaged members was proposed in order to ensure the safety of the structure. Enlarging section reinforcement method, Polymer Mortar and gluing CFRP methods were adopt to strengthen the beams, columns and floor slab depending on the damage degree of the concrete member.The idea of dealing with the industries building damaged by fire can provide us a good reference of repairing the similar industries building.

Based on the mechanism of mass and heat transfer of the particles and air in drying tube，the mathematics model of pneumatic drying process was established which referred to straw fuel in straight horizontal tube. The simulating results were summed up. Test bed of pneumatic drying was established，the test results were summed up by making single-factor test on the test bed. The results of simulating and single-factor test were coincided, and the pneumatic drying process was divided into two parts which were high-speed drying area and slow drying area. The effect factors were analyzed which were initial water content, hot air temperature, mass of hot air and materiel. The most important factor in gas flow drying on straw fuel was summed up which was the mass of hot air.

Papermaking waste liquid instead of water to prepare coal water slurry, which aim is turning waste into treasure. Not only can the waste fundamentally eliminate environment pollution, but also saving a lot of water resources. Because the waste contains large amounts of sodium, which is one of the main reasons of heating surface slagging of boiler. So it is necessary to improve and increase the soot blowing device of heating surface of boiler.

In roughage, ten trace elements as Pb, Se, Mn, Se, Zn，Sb, Hg, Sn, Ca, Mg were detected by ICP-AES. Method of high pressure nitrifying pot is also selected to nitrify roughage. The relative standard deviation of measurement was less than 2.60%. The results accord with the demands of analysis trace elements. The experiment proved that roughage contained rich useful trace elements, which was green food with high nutrition.

This article makes a systematic analysis of the formation mechanism of coalfield fire and the progress of research on the extinguishing and control technology, lays the stress on the exposition of the findings from the researches made by the scholars at home and abroad from two aspects such as the breakout, development and evolution mechanism of coalfield fire and the extinguishing and control technology for the coalfield fire, including the coalfield fire combustion reaction kinetics mechanism, coalfield fire zone coal petrology fluid solid thermal coupling mechanism, coalfield fissure medium mass transfer model, research on natural convection and porous combustion characteristics, coalfield fire detection and identification, monitoring and control technology, extinguishing and control technology, process and material, and still considers the accurate detection and identification of the fire source position, new grouting extinguishing material and process, and the action mechanism of the environmental impact as the difficulties to be solved immediately.

Visual technology and three-dimension modeling of Geologic bodies have important meaning in the fields of geological research and resource explore. Based on TIN surface, this paper realizes the model reconstructing of stratified geological entity three-dimension, with the aid of three-dimensional graphic library OpenGL, the visualization and any section view of geological three-dimension model can be achieved, which offers powerful support for excavating the information of 3D geological model

It’s very important that Bridge Structural Health Monitoring to bridge management and maintenance. In this paper,the authors study the Application of GIS and GPS in Bridge Structural Health Monitoring. Introduce the application field of GIS in bridge structural health monitoring and the method of GPS-RTK Technology to measure the bridge three dimension dynamic coordinate, proposed the System General Framework of GIS in Bridge Structural Health Monitoring,mainly study the problems that acquisition and collection of Monitoring information,the database management scheme of the system, the method that of GIS manage Spatial and attribute information which related to bridge structural health monitoring and to process and analysis the Monitoring data. Also analysis the feasibility of using GPS and GIS technology in a Bridge Structural Health Monitoring.

Three-dimensional Geologic body modeling is one of the core problems in geological information system. The current situation of three -dimensional geographic information system (GIS) and method of space modeling were analyzed in geological field, a kind of three-dimensional geological space modeling method-Similar Tri-Prism(STP) was put forwards, STP Combined with the characteristics of Geological body engineering. This method took Similar Tri-Prism body as the basic volume element of three-dimensional geological modeling, and described the data structure of Similar Tri-Prism body by using five basic elements and six groups of topological relationships. It can effectively express all kinds of three -dimensional geological phenomenon, can better combined with traditional multi-layer triangular irregular network (TIN) model, as well as maintain the topological relationship of space entity. An initial prototype has been developed basing on the modeling method in this paper and proved by real drilling data,which is suitable for three -dimensional GIS in geological field.

A conceptual laboratory model for studying unsaturated flow in a single fracture-matrix system is developed in this paper. The model is capable of simulating the fracture and matrix with different samples, and three groups of contrastive experiments are conducted under a constant rainfall. The results show that fracture-matrix interactions have a great effect on the hydraulic properties of the fracture and matrix. The more distinctive the sample used to simulate the fracture and matrix is, the greater the influence is. Furthermore, the wetting front along the matrix runs ahead of that along the fracture, resulting in an extra water source for the fracture. It could be concluded fracture-matrix interactions and unsaturated hydraulic conductivity of the matrix cannot be ignored when the fracture is surrounded by a permeable matrix.

Reconstruction and visualization of three-dimension bed have important meaning to geology explaining and information Obtaining. This paper realizes three-dimension of the stratum model, based on TIN multilevel DEM method, with the aid of OpenGL, it realizes three-dimension visualization of stratum model, and carries on operations of illumination, roams and cuts etc.

The urban-rural integration is suggested to be used in the urbanization of Changsha-zhuzhou-Xiangtan (CZT),according to the characteristics of the space linking up three cities on the basis of the existing research results . the landscape pattern of the space should be small cities-towns-forest land-cropland -water area by insisting on the rule of people-oriented and the natural environment least destroyed.The space should be environment-friendly that the model of the big city construction doesn’t be totally copied.At last,the suggestions on the basic characteristics of the space pattern are put forward

In this paper, the computation fluid dynamics ( CFD) software FLUENT is applied to analyze the internal 3-D gas flow of the mechanical turbulent coal pulverizer impeller, especially on the pressure and velocity distribution. Eddy current-wake and secondary flow phenomenon is found in the pulverizer.

The fluid level of swabbing wells with packers or without packers is different from other wells’ when the swabbing wells are stopped swabbing, because the effect of gravity differentiation is obvious, which is used to calculate the sand face pressure. In the homogeny reservoir, flow mathematic model of build-up of fluid swabbing well in circular sealed stratum is built up under considering the well bore effect and skin factor. Then, the non-homogeneous equation’s exact solution in Laplace space of the model are acquired by using theory of Laplace transform and Bessel function ,then the chart of type curve and the matching of type curve are analyzed. Finally, the software of swabbing well’s fluid level build-up is developed which is used to calculate the formation parameters that are fitted the formation parameters calculated with other methods.

Based on the mechanism of mass and heat transfer of the particles and air in drying tube, the mathematics model of pneumatic drying process was established which referred to straw fuel in straight horizontal tube, and the equations were solved by Runge-Kutta integration method. Then, by analyzing the thermal factors of gas flow drying，the most important factor in gas flow drying on straw fuel was summed up which was the mass of hot air. The method of orthogonal experimental design was used to analyze the whole process of gas flow drying, and primary and secondary roles led to the conclusion, which were the mass of hot air first , the equivalent diameter of the fuel granule and the temperature of hot air.

Current status of the direct spinning production lines in high unit capacity of the polyester textile fibers in China are investigated, as well as the status and development of flexible production technique.

According to the analysis of the characteristics of the biomass straw in its pneumatic drying process, some reasonable assumptions concerning the pneumatic drying are made and the mathematical model of heat and mass transfer in the biomass straw’s pneumatic drying process in the horizontal straight tube. Besides, the numerical method is adopted to solve the model and the analog simulation concerning the moisture content, temperature and the speed changes of the material and the air is conducted. Meanwhile influence of the gas-solid ratio and the air flow’s initial temperature on the drying effect is the analog simulated and the reason for this phenomenon is also analyzed.

Mn18Cr2 steel is one of austenitic deformation strengthening steel. The existing form of TiN and its influence on the austenitic structure in the steel by adding small amounts of TiN nanoparticles are discussed in this study, which may provide some advices to explore new way to strengthen high manganese steel. The microstructures of Mn18Cr2 steel added small amounts of TiN nanoparticles are observed by Transmission Electron Microscopy (TEM). The results show that TiN nanoparticles exist in austenite and there have a very good match interface between the two phases, the crystal face relationship are {220}γ//{220}N, {422}γ//{422}N, (111)γ //(200)N , orientation relationship are γ// N, γ//N, [112]γ // [011]N, moreover, the relationship of (111)γ and (200)N is not only parallel but also coherent. Meanwhile, there are many high density dislocations, a small amount of stacking faults, twins and ε-martensite in the austenite due to the role of TiN nanoparticles.

The power battery was manufactured with the commercial LiMn2O4 and graphite, and its storage performances with different charged state were studied. Structure, morphology and surface state change of the LiMn2O4 before and after storage were observed by XRD, XPS and AC technique, respectively. The result shows that the capacity recovery of LiMn2O4 stored at discharge state is best (99.2%). While that of full-charged state is worst (93.6%). The cyclic performance of LiMn2O4 stored at full-charged state is best (capacity retention ratio of 89.8% after 200 cycles), while that of before storage is 83.0%. The crystal of the spinel was destroyed after storage, and the intensity of breakage is increased with charged state increasing. The amount of soluble Mn and Li-ion migration resistance (Rf) are increased with chare state increasing, and the oxygen loss is detected.

After the temperature medium voltage coal boiler changed to burn biomass, the quantity of the smoke greatly increased, the economizer heat increased and the boiling rate rose, which tends to cause the economizer’s tuber wall to overheat. In this article, the calculation formula of the economizer’s tube’s outside surface temperature and the average temperature are deduced based on the basic thermal law. Besides, by measuring the economizer’s wall temperature, the relation between the wall temperature and the boiling rate is attained and two limit boiling rate concepts which judge the safe work of the economizer are also put forward. What’s more, the window procedure which calculates the wall temperature and the limit boiling rate is also compiled. In the end, the authors summarize the rapid- increasing change rule of the wall temperature between the two limit boiling rates and hold that the biomass boiler boiling rate should be controlled below the first boiling rate.

The multiple-shear dowel connection with slotted-in steel plates is one of the most efficient joints for large cross section timber structures. Experiments were performed on dowel-type timber connections with one, two and three slotted in steel plates under lateral loads parallel to the grain. Test variables include the number of steel plates, the spacing of the steel plates, and the dowel diameter. Results show that the load-carrying capacity of the dowel-type connection increased as the number and spacing of steel plates in the same thickness of timber specimens. Finally, a model of the load-carrying capacity of multiple shear steel-to-timber connections is presented, which showed good agreement with the results obtained in the experiment.

The dissolve behavior and cathode protection performance of Al-Zn-In-Mg-Ti anode was studied by electrochemistry impedance spectrum technology, weight-loss measurement and SEM in natural corrosion and self-discharge experiment. The results show that the 7A52 corrosion rate was decreased at a certain extent which under the protection of sacrifice anode in the self-discharge experiment, but the protection was inefficient and sacrificial anode corrosion products fell off uneasily. Natural corrosion sacrifice anode surface influenced by the corrosion product and the oxide film, the number of active pot was reduced with the progress of experiment.

In order to decrease the cost of the material and energy during the forging process, multiple preform die shape optimization design was carried out in this paper. Based on the FEM, a sensitivity analysis method was used to perform the optimization procedure. The shape of the forging and deforming force of the final forging was used to express the cost of material and energy respectively. Using the weighted sum method, the total objective function was gotton. The coordinates of the control point of the B-spline used to represent the preform die shape was determined as the optimization design variable. The sensitivity equations of the total objective function with respect to the design variables was developed. The multiple objective perform design optimization software was developed by FORTRAN language. And then, the preform die shape of an H-shaped forging process is optimized. The total objective function, sub-objective function, the shape of the preform die and the final forging during the optimization were given. After the optimiztion, a near net shape forging was obtained. At the same time, the deforming force decreased. The optimization results are very satisfactory.

A series of novelbis-indolylmethanes containing 1,2,3-triazolyl have been synthesized from the reaction of indoles with 4-formyl-1,2,3-triazole catalyzed by Brønsted acidic ionic liquid [PyNCH2CO2H][HSO4] under solvent-free conditions. The satisfactory results were obtained with excellent yields and short reaction time in the experimental procedure.

This paper introduces the design of generally remote transmission system with high reliability and multi-transmission-channels. Using a high-speed 32-bit ARM ® Cortex ™ - M3 processor, with multiple network transmission channels, it can be applied to complexly industrial field for reliable data transmission. The system has been successfully applied in Internet of Things of fire networking, which shows that it has high data reliability and a good utility value in the transmission process of the system.

Biomorphic SnO2/C ceramic has been prepared by molding into a composite billet and carbothermal-reduction under vacuum from ramie fibers/Sn(OH)4 precursors. The phase composition and microstructure of the prepared samples were characterized. The effects of the carbonization temperature and the other factors on the crystal structure, morphology and ingredients of the prepared samples were discussed. The results showed that there is no peak corresponding to carbon. So, it is inferred that the carbon exists in amorphous form and the sintering temperature have significant effects on the microstructure of SnO2 in biomorphic SnO2/C ceramics. The prepared products at the sintering temperature between 480°C and 630°C are biomorphic SnO2/C ceramics.

A harmonic balance approach has been developed to compute nonlinear viscous unsteady flows around oscillating blades. The computed results using two orders harmonic balance method are compared with those by conventional dual-time stepping method. Results obtained with the present method agree well with those from dual-time stepping method, which demonstrate the ability of the present analysis method to model accurately the unsteady flow. Furthermore，the present method is highly efficient. It is about 36 times fast than conventional dual-time stepping method in the present computation. Then the effects of oscillation amplitude and reduced frequency on unsteadiness of flows are studied. The analysis exploits the fact that, (1) the hysteresis effect of unsteady flow is hardly affected by oscillation amplitude, but the first harmonic unsteady pressure across the blade is proportional to oscillation amplitude; (2) the higher the reduced frequency, the wider the range of unsteady aerodynamic forces, the more intense the hysteresis effect.

The solubility and cathodic protection performance of Al-Zn-In-Mg-Ga-Mn sacrificial anode in natural corrosion and self-discharge experiment was studied using electrochemistry impedance spectrum technology, weight-loss measurement and SEM. The results show that the corrosion rate of 7A52 was decreased under the protection of sacrificial anodes in the self-discharge experiment, and sacrificial anodes dissolved uniformity due to the effect of active location, the corrosion products are easy to shed. Only location corrosion occurs on the sacrificial anode’s surface which is influenced by corrosion products and oxide film in natural corrosion experiment.