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The BaFe12O19 nanoparticles was prepared by sol-gel method in different temperature (750°C,850°Cand 950°C), and then BaFe12O19/polyaniline nanocomposites was synthesized by in situ polymerization. The XRD, FTIR spectra, SEM and vector network analyzer were used to analyze the "" chemical component, morphology and microwave absorption property of the nanocomposites. The result show that BaFe12O19 can be generated at 750°C without any impurity ,and its size increased with increase of calcination temperature.BaFe12O19 nanoparticle was coated with polyaniline partially, and we can get it have interaction with polyaniline through FTIR spectra. While the ferrite calcined at 850°C,the thickness of the absorbing material is 4.5mm,the nanocomposites have the largest reflection loss of-17.6 dB at 6 GHz,and its reflection loss values less than−10 dB in the range of 5-7.4GHz.

Kinematics analysis is important to analyse and design planar gear transmission mechanism. Planar gear transmission mechanism is composed of two basic loop units. The kinematics analysis equation of the basic loop units is established based on the constituent characteristics of planar gear transmission mechanism and the motion relationship of every component in each basic loop unit. The kinematics analysis mathematical model of planar gear transmission mechanism is constructed by using the basic loop group units of planar gear transmission mechanism. With Windows XP as the platform, Visual Basic 6.0 as a tool and object-oriented programming method, a set of common software has been developed for kinematics analysis on planar gear transmission mechanism. The software has many advantages, such as simple operation, strong man-machine interaction, friendly interface and strong commonality.

In order to deal with the more and more serious problem of electromagnetic radiation pollution, cement-based composites were prepared by introducing glass fiber into cement as through wave reagent and carbon black as absorbing reagent . Arched testing method were used to test the reflection losses in the frequency range of 2~18 GHz. The results showed that the absorption properties were improved in high frequency compared with the pure cement. The filling ratio of carbon black and glass fiber as well as the thickness of samples had influence on the absorption properties. The lowest reflection loss of-11.2 dB was obtained at 18 GHz of 9wt.% glass fiber and 5wt.% carbon black filled cement with thickness of 10mm. The new material can be used for building indoor electromagnetic radiation protection.

Teaching English as a foreign language (TEFL) has always been paid great attention to ever since English was officially recognised as the first foreign language in China in 1964. The evident advantages of applying computer science and information technology in TEFL have been recognized by the government leaders, educational researchers, teachers and the students. Numerous researches and efforts have been made to integrate modern technology into TEFL and some progress has been achieved. However, the overall results fall short of expectations. To a certain degree, the computer aided language learning (CALL) in English in Chinese mainland is still at its infant stage and great potential of computer science and information technology in facilitating TEFL has not been fully realized. After exploring the current situation of the CALL in TEFL in Chinese mainland, this article categorizes the problems from personal, administrative, technical, economic and conceptual aspects. Based on the exploration of the current state and the problems existing, several suggestions are put forward for the normalization of CALL in TEFL in the Chinese mainland.

Due to the differences between the historical background, technological advancement, economic situation and population density between America and China, there are many differences between American and Chinese education systems. One of the differences is the applied technology in web application in education. By comparing the general technological situations in the two countries and the applied technology in web application in online education, web-facilitated education at college level, K-12 level and the developing prospects in the two countries, the article comes to the conclusion that applied technology in web application in American education is much more advanced than that in Chinese education. The web-related infrastructural construction in American educational institutions has almost come to a complete state and now more concern is on how to make full use of all the facilities and technology so as to achieve the best result, while China is still trying hard to make web-related facilities reach all the educational institutions and at the same time searching optimized ways of application. Insufficient financial support, lag in technology and deep-rooted traditional test-oriented teaching philosophy among teachers as well as parents are the greatest obstacles to the widening of applied technology in web application in education in China. Although government have been trying hard to deepen the application of internet technology in education by putting out a series of policies and starting a succession of projects and great progress has already been made and will be achieved, there is still a long way to go before it reach the present state of American applied technology in web application in education. However, to what extent and in what way should China apply internet technology in education should be carefully studied since there are so many cultural differences and national situations between China and America. A lot of research are to be done and the findings of researches already done about applied technology in web application in education world-wide should be learned so as to avoid waste and guarantee efficiency.

Regenerative braking is one of the key technologies to improve the energy efficiency of electric automobile, but there is no available scientific method to evaluate the effectiveness of regenerative braking for electric automobile. The paper research regenerative system conformation and control strategy .An efficiency evaluation index of regenerative braking system is introduced based on brake energy flow model.

Ni-doped ZnO diluted magnetic semiconductors nanorods were successfully synthesized by hydrothermal method. The crystal structure, morphology, constituent elements and optical proprety of the products using this method were investigated via X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray energy dispersive spectrometry (XEDS) and ultraviolet-visible spectroscopy (UV-vis). The experiment results show that the morphology of samples were nanorods with good dispersion, all the diffraction peaks correspond to the wurtzite structure hexagonal phase, no other impurity phase appeare, and the Ni2+ions successfully substituted for the lattice site and generate single-phase Zn1-xNixO. The band gap increases firstly and reduces afterward with the increase of Ni2+contents.

The nanoscale magnetic composite powders BaFe12O19-ZnFe2O4 were prepared by two-step citrate sol-gel, with analytically pure Fe(NO3)3、Zn(NO3)2 and Ba(NO3)2 as the main materials. The XRD, TEM and VSM were used to analyze the structure, feature and magnetic property of the nano-powder. The results show that the same presoma is calcined in 600°C、650°Cand 700°C obtained BaFe12O19-ZnFe2O4，XRD display for both pure phase, do not contain any mixed phase。The higher the temperature, the content of magnetoplumbite phase increased, corresponding the content of spinel phase low。By hysteresis loop of composite powde BaFe12O19- ZnFe2O4 can see, simple substance BaFe12O19 magnetoplumbite phase has the wasp waist shaped hysteresis loop，simple substance ZnFe2O4 spinel phase has superparamagnetism，but the nanoscale composite powders BaFe12O19-ZnFe2O4 has rectangular hysteresis loop。

Small span arch steel structures on spring-settlement support and normal support were designed as research objects. 1kg, 2kg, 3kg and 5kg TNT group charges were detonated respectively on the center surface of backfill above the structure. Numerous data was obtained during these tests. The comparisons of measured parameters were done between the structure with spring-settlement support and normal support. The results indicate that, the structure with spring-settlement support can reduce the magnitude of internal force of the structure, decrease the dynamic effects on the structure significantly, and enhance the bearing capacity.

In order to resolve the theorized design problems on the bionic non-smooth drag reduction surface of an arc-shaped revolution body, which mainly include the structure morphology and spatial arrangement of the non-smooth point, a kind of designing method on the bionic non-smooth drag reduction surface is presented based on biological phyllotactic theory, and the mathematical equation of the arrangement of the non-smooth point on the arc-shaped drag reduction surface has been established, the effects of the phyllotactic parameters on the arrangement form and density of the non-smooth point have been discussed, and the arrangement of the non-smooth point on an arc-shaped revolution body surface has been designed by using a 3D software. Research results have shown that the arrangement density of the non-smooth points increases with the decreasing of the phyllotactic coefficient, and the area ratio of the no-smooth point to the surface of revolution body increases with the geometric parameter of the non-smooth point.

The surface texture of polishing pad is a key factor which determines the performance of polishing pad, and by altering the geometrical pattern of polishing pad surface, the surface texture of polished workpiece can be improved. In this paper, based on phyllotaxis theory in biology, the polishing pad with phyllotactic pattern has been designed and the effects of phyllotactic parameters on the surface texture of polishing pad have been discussed. Lastly, the polishing pads with phyllotactic pattern have been made with lithography and composite plating technology, and the influence of correlative plating parameters on plated coating have been investigated. The results indicated that the abrasive grain block density increase with the increasing of the diameter D of abrasive grain block and the decreasing of phyllotactic coefficient k, and the quality of electroplating is optimal when current density is 1A/dm2 and temperature is 30°C.

In order to achieve the controllability of the abrasive arrangement on the working surface of grinding wheel,a new kind of the superabrasive grinding wheel, which has defined abrasive grain cluster pattern, has been designed based on the phyllotaxis theory of biology, and fabricated with UV lithography method and electroplating technology. The analytical results indicate that the phyllotactic parameters influence on the abrasive arrangement configuration on the work surface of the superabrasive grinding wheel, so as to improve grinding performance of the grinding wheel, increasing the diameter of phyllotactic abrasive grain cluster and decreasing phyllotactic coefficient can increases the abrasive grain density of the surperabrasive grinding wheel surface. Electroplating experimental results show that the reasonable electroplating processes can reduce the faults of defined abrasive arrangement on the superabrasive grinding wheel surface.

Based on models of a porous electrode, a more accurate lattice Boltzmann model for simulating the performance of a solid oxide fuel cell (SOFC) is proposed. Results show good agreement between simulated and measured data. The accuracy of concentration over potential prediction is crucial for low reactant concentrations. The addition of a small amount of air to the fuel yields fully stable performance without measurable carbon deposits detected on the catalyst layer or the fuel cell. Cell performance increases with the temperature. As a first test of the model, a benchmark problem regarding the performance of an internal reforming solid oxide fuel cell (IR-SOFC) is investigated. When the catalyst activity decreases, the rate of methane conversion decreases near the reactor

Light-weight radar absorbing material (RAM) based on resistive frequency selective surfaces (FSS) was designed and prepared. The principle of the resonances of the RAM was analyzed by calculating the impedance of the FSS and the grounded substrate according to the equivalent circuit method, and the results show that a wideband absorbing structure can be gained by producing two adjacent resonances. After design and optimization by Genetic Algorithm (GA), the RAM with absorbing bandwidth of 7.5~18GHz below -10dB was obtained, whose thickness is only 3mm. The designed RAM was gained by preparing resistive patches on the grounded dielectric substrate of rigid polyurethane foam using screen painting technology. The density of the absorber is only 0.2g/cm3, the reflectivity was measured and it shows that the experimental result is consistent with the design one.

In order to make the contact pressure distribution of polishing wafer surface more uniform during chemical mechanical polishing (CMP), a kind of the bionic polishing pad with sunflower seed pattern has been designed based on phyllotaxis theory, and the contact model and boundary condition of CMP have been established. Using finite element analysis, the contact pressure distributions between the polishing pad and wafer have been obtained when polishing silicon wafer and the effects of the phyllotactic parameter of polishing pad on the contact pressure distribution are found. The results show that the uniformity of the contact pressure distribution can be improved and the singularity of the contact pressure in the boundary edge of polished wafer can be decreased when the reasonable phyllotactic parameters are selected.

The thin-walled cavity workpiece with insufficient rigid property is liable to deform during the machining process and the request of accuracy is very strict. The paper takes typical aeronautic aluminum-alloy for example, fixture is an important consideration in the operation. To reveal the influences of locating points, clamping sequence and loading ways on the distortion of thin-walled cavity part, finite element models were established to simulate the clamping operation. The result shows the preferable scheme is that the distance of the clamping locations are far each other, clamping forces are firstly applied on the surface with high rigid and all clamping forces are applied in many steps. The scheme can effectively control the deformation of clamp ,and furthermore improve the machining accuracy.

In order to obtain the contact pressure distribution between the hard disc substrate and the polishing pad and its effects on the profile of polished substrate surface, the elastic contact mechanical model and mathematical equations on the chemical mechanical polishing of the hard magnetic disc substrate are established, and also the relevant boundary conditions are put forward. The contact pressure distribution is calculated with FEM, the polishing experiments are carried out and the surface profiles of polished substrates are obtained. The study results show that the contact pressure distribution on the substrate surface is non-uniformity and the contact pressure in the substrate edge present biggish undulation. Choosing properly the Young’s modulus of the polishing pads and decreasing its Poisson’s ratios can make the uniform area of the contact pressure distribution enlarging and improve the flatness of polished substrate.