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The new method of laser prestressed bending of Titanium alloy sheet is put forward in this paper. Titanium alloy sheet is produced pre-deformation by a clamp, the laser beam with some certain intensity scans its surface along the given path, and it is formed due to the thermal effect of the laser to reduce the yield strength of the scanning area and enhance its plastic deformation ability. A feasibility experiment for Ti-6Al-4V sheet is done and the bending effect is remarkable. Laser prestressed bending mechanism is described and the main influence factors are analyzed.

Pure eulytite Bi4(SiO4)3crystals were prepared by high temperature melt cooling method using Bi2O3and SiO2as starting materials. In this study, the properties of the samples were characterized by thermo gravimetric (TG),differential scanning calorimeter (DSC), field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). The results showed that eulytite Bi4(SiO4)3was crystallized when high temperature glass-melt were cooled to 943°C and obvious exothermal peak is shown on the DSC curve; and pure eulytite Bi4(SiO4)3crystals were synthesized by keeping the processing temperature for 8 hours. Bi4(SiO4)3grains grew larger and the amount of vacancy increased along with the extension of holding time, while Bi4(SiO4)3grains still presented a structure of partial ordering. Eulytite Bi4(SiO4)3prepared through melt-cooling method is of high purity and good stability, and can be applied as starting materials of preparation of Bi4(SiO4)3thin film and high quality Bi4(SiO4)3macrocrystal.

The sound transmission loss (STL) of the acoustic parts in the vehicle was proposed to be computed using the Sound Pressure Level measured at the several locations inside the vehicle and the transmitted Sound Intensity Level on the vehicles exterior panel, which the acoustic treated vehicle passenger compartment is assumed as a small reverberation room. The necessary parts retrofits and acoustic treatments for Sound transmission loss tests of the acoustic parts in the vehicle were listed. The values of the appropriate number and positions of the loud speakers, microphones and sound intensity probes for Sound transmission loss of the acoustic parts in the vehicle were recommended. The in vehicle sound transmission loss tests of the acoustic parts such as the doors, carpets, wheel house etc. were achieved in the semi-anechoic room. Based on the door system, the correlation work has been done among the methods of the proposed in vehicle STL test, the reverberation - semi-anechoic chamber buck STL test and SEA analysis.

In this paper, an experimental study on the powertrain in vehicle sound power test was presented. The necessary parts retrofits and acoustic treatments for the powertrain sound power test in the vehicle were listed. The criteria and correction method of the appropriate background noise level for the powertrain sound power level test in the vehicle were discussed. The powertrain sound power tests in the vehicle were achieved in the low noise chassis Dynamometer in the semi-anechoic chamber. Based on the test results, the acoustic component contributions for the powertrain sound power levels were given .

Harmonic components in holospectrum are mainly due to the lateral vibration, and they are important parameters in fault diagnosis of rotating machinery. However, defects on measuring shaft surface are also included in harmonic components in holospectrum and may lead to misdiagnosis. It’s necessary to study a method to identify the shaft surface defects. Based on the manufacturing process of outer round, this paper studies the forming mechanism of harmonic defects on outer round and their characteristics in holospectrum. An experimental example is also given to validate the theoretical analysis, and the results show that holospectrum can recognize the harmonic defects on outer round well.

Metastable crystal Bi2SiO5 has significant properties including dielectric, thermoelectricity and nonlinear optical properties. Metastable crystal Bi2SiO5 has been successfully prepared by melt cooling method in this study. Surface tension of high-temperature melt Bi2SiO5 was measured by Suspension method; metastable crystal Bi2SiO5 construction was assigned by IR(Infrared Radiation). The experimental result showed that Bi2SiO5 flux density decreased with the increasing temperature in 830-1095°C range; surface tension changed quadratic with the decreasing temperature. The [SiO4]4- anions of Bi2SiO5 originated from the isolated [SiO4] tetrahedron in the glass to a chain connected structure.

Polyaniline nanorods, nanoplates and urchin-like structures have been synthesized successfully by the template-free method of aniline and peroxo–polytungstic acid using ammonium persulphate as the oxidant in aqueous solution. The peroxo–polytungstic acid concentration and reaction temperature play important role in the formation process of polyaniline nanostructures. As the precursor concentration increased to 0.29mol/L, nanorods and urchin structures were obtained. With the decrease of temperature, the amount of PANI nanoplates with radially aligned dendritic surface structures will increase. The radially aligned dendritic surface is probably due to the molecular structures of the dopant, the linear nature of PANI chains and the second nucleation formation.

Poly (aminohexylaminomethyl/phenyl) silsesquioxane (PAHAMPSQ) microparticles with diameter of 350 nm were synthesized by the hydrolytic condensation of aminohexylaminomethyltriethoxysilane (AHAMTES) and phenyltriethoxysilane (PTES) in the presence of H2O by using tetraethylammonium hydroxide (TEAOH) catalysts. PAHAMPSQ containing both aminohexylaminomethyl and phenyl groups were confirmed from FT-IR, TGA. XRD patterns indicate that a certain ordered structure existed in PAHAMPSQ molecules. Contents of amino of PAHAMPSQ were determined by elemental analysis. SEM images show both granular and flake exist in PAHAMPSQ microparticles. Yield of PAHAMPSQ in different AHAMTES/PETS molar ratios was about 80%. PAHAMPSQ offers the potential utility as building blocks for divers and novel organic/inorganic materials.

In this paper, Ni0.5Zn0.5Fe2O4ferrite ceramics were produced with Ni0.5Zn0.5Fe2O4powders prepared by reaction in a molten salt using Fe2O3, NiO and ZnO powders as raw materials. Ni-Zn powders were characterized by X-ray diffraction (XRD). Density and shrinkage in diameter of Ni0.5Zn0.5Fe2O4ceramics were measured. MicroSubscript text structures were observed using field emission scanning electron microscopy (FESEM), and magnetic properties were examined by HP4291B impedance analyzer. XRD pattern indicated that the powders synthesized at 900°C for 1h were pure spinel Ni0.5Zn0.5Fe2O4phase. Via the measurement of density and shrink in diameter, optimal temperature was 1200°C and holding time was 2h, which was in accord with the results concluded from micrographs. FESEM images illustrated that the average grain size increased with increasing holding time, which followed the Ostwald liquid growth mechanism. At lower frequencies, the initial permeability (μi) increased from 86.65 to 183.48 with increasing holding time, while the threshold frequency decreased from 13.3MHz to 8.52MHz, which implied the initial permeability (μi) variation complied with the Snoek law to some extent.

Polyaniline/SiO2 composites were prepared by the SiO2 particles whose surface character was modified by succinic acid. The composites were characterized by Fourier transform infrared (FT–IR) spectroscopy, X–ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscope (SEM). The results demonstrated that the thermal stability of PANI had improved.

α-Al2O3platelets were prepared in the interface of Na2O-CaO-SiO2glass induced by Al. The morphology of the platelets was observed by Environmental Scanning Electron Microscopy (ESEM). The platelets are irregularly shaped at 720°C for 30mins and share mean thickness of 200nm. EDS shows that the platelets are rich in Si, reasonably due to the formation of Al-Si eutectic. At 1200°C, the prepared platelets have mean diameters between 400nm and 1000nm, most of which are aggregated and part through intergrowth. The crystals develop from the glass and can form good moistening with the glass matrix.

Hydroxyapatite (HA) was synthesized in presence of 20wt% m-ZrO2by solid state reaction between tricalcium phosphate(TCP) and Ca(OH)2at 1000 °C for 2h. Similarily, Fluorine hydroxyapatite(FA) was synthesized using tricalcium phosphate and calcium fluoride as raw materials at 1000 °Cfor 3h. The as-prepared HA was mixed with 10%,25%,45%,55%,70wt% FA and the mixture was sintered at 1000°C-1400°C for 2h. The main phase and bulk density was measured. The results show that when the relative amount of FA to HA increased, the decomposition of the composite is decreased gradually because of the formation of thermally stable FHA solid solutions. Low temperature would effect the exchange of ionic between FA and HA,while high temperature would impact synthesis of composites, because high temperature would lead to dissolution of HA ,which has to react with FA. Increase the content of HA would be advantage for synthesis FHA-ZrO2composite.

α-Al2O3 platelets were prepared in the interface of Na2O-CaO-SiO2 glass induced by Al. Phase identification was accomplished by X-ray diffraction analysis. The morphology of the platelets was observed using an Environmental Scanning Electron Microscopy (ESEM). The changes for the mixtures of the Al powders and the glass powders that occurred during heating were characterized by a combination of differential scanning calorimetry (DSC) and thermalgravimety(TG) on a multi-functional instrument. Confirmed by XRD and ESEM, at 1200°C, the prepared platelets have mean diameters between 400nm and 1000nm. Most of them are aggregated and part of them through intergrowth. The crystals develop from the interface between glass and Al, and can form good moistening with the glass matrix. DSC/TG shows that γ-Al2O3 formed by oxidation of Al, transforms into α-Al2O3 and grow into the platelet α-Al2O3 crystals owing to the molten Al and the molten glass. On the other hand, part of the molten Al erodes into the glass and makes the deviation of the Na2O-CaO-SiO2 ternary system into Na2O-Al2O3-SiO2 ternary system, resulting in the formation of NaAlSiO4.

Pure Bi12SiO20powder was successfully prepared by a molten salt method using Bi2O3and SiO2as raw materials and using KCl-K2CO3as flux at 635°C with the heating rate of 5°Cmin-1. The phase composition and microstructure of these products were analyzed by X-ray diffraction and scanning electron microscopy, and the effects of the processing parameters, such as the ratio of Bi2O3/SiO2, calciniation temperature, isothermal time and relative amount of salt, on the composition and particle size were investigated. The results indicated that regardless of changing the ratio of Bi2O3/SiO2, calciniation temperature, isothermal time or relative amount of salt the reaction only yielded Bi12SiO20without Bi2SiO5and Bi4Si3O12. Henceforth, KCl-K2CO3molten salts may be considered as an ideal reaction medium to synthesize pure phase of Bi12SiO20. The particle size of Bi12SiO20phase can be determined by changing the temperature, isothermal time and relative amount of salt.

Many automobile security systems are provided today, but their functions are not enough to satisfy the applications for Environmental Monitoring based on Service Oriented Architecture (SOA).In this paper, we proposed and introduced new device which is an automobile information Identification device with sensors network to strengthen automobile security system function for monitoring environment. This device aims at monitoring status of automobile as well as its environment by collecting data through sensors network. In order to increase the security, we used a new designed architecture of sensors network to gather data. GPS and GPRS were also added to locate the automobile and to transmit filtered data into the monitor. A New Design approach of system was discussed on both software and hardware. One math model for showing gas and voltage value relation was established. In order to improve system reliability, various testing methods were applied in this system. The results showed that the combination of average filtering algorithm and median filtering algorithm to inhibit interference signal at variety of frequency case can effectively filter different frequency interference signal in the software system. The advantage of this system was discussed. The system has low cost, high performance, real-time and reliability characteristics. It can not only strengthen current security system functions but also can satisfy requirements of future automobile. It also has large potential market.

Based on ARM,multifuncttion GPS/GPRS automobile security system was designed,which focused on security and detectiong.The system combines with detection technology, sensor technology, GPS technology, GPRS technology and digital filtering technology.This system was discussed from software and hardware. Related math model was established. Corresponding test was been brought forward to improve system reliability. Average filtering method and median filtering algorithm have been used to inhibiting interference signals with variety of frequency in software. In this paper,the advantages of this system have been discussed.The embeded system realizes the function with characteristics of low cost, high performance, real-time and reliability ,it has high practical value.

GA approach suitable for solving object Recognition problem is described and evaluated using a series of simple model problems. Usually GA calculation produces enormous amount of data that contains rich information, of which only a tiny section is commonly utilized runs through the design optimization. An application of Genetic Algorithm optimization with Noise characteristics would give many insights into how to allocate various image reconstruction options in different echelons, GA employing a global search might identify a better solution in an different area of the search space.

A large-sized high-quartz translucent porcelain plate was developed, which has good decorative effect and market prospects. The light transmittance of the high-quartz translucent porcelain plate (Its thickness: 3.6mm) reaches 0.72%. Compared to other large-sized translucent plates, large-sized high-quartz translucent porcelain plates have obvious advantages about mechanical properties, glossness and the price.

Good crystallized Hydroxyapatite was synthesized using H3PO4 and Ca(OH)2 as raw materials by wet chemical method and sintered at 800°C for 3h. The as-prepared HA powders were mixed with 15%, 20%, 25% yttria-stabilized m-ZrO2, respectively, and sintered at 900°C- 1200°C for 1h, respectively. The main phases and rules of phases changing with the content of yttria-stabilized m-ZrO2 and sintered temperature was investigated by XRD and the microstructure features of the composite powders were analysed by scanning electron microscopy. The results show that when the temperature is at 1000°C, HA starts to decompose to β-TCP and CaO, the m-ZrO2 is then partly converted into t-ZrO2 by partial consumption of CaO, which in turn results in a mixture of β-TCP and HA further. The CaO produced reacts further with m-ZrO2 generating a mixture of t-ZrO2 and CaZrO3 in different proportions. The microstructure of the HA-ZrO2 composite further indicates that when sintered at 1000°C for 1h, gray slice area represent a mixture of HA and a small amount of β-TCP. While in the white area, some spheric ZrO2 mixed with a negligible amount of CaO. When sintered at 1200°C, distinguished reduced spherical ZrO2 particles embed within mixed HA and β-TCP, which change from slice to agglomeration. As a result, when the sintered temperature is about 1000°C and the addition of m-ZrO2 reaches 20wt%, superior main phases are HA and t-ZrO2, which improves the combination of mechanical and biological properties.

Hydroxyapatite (HA) doped with 3% Yttria-stabilized 20vol%m-ZrO2composite were synthesized by solid state reaction between tricalcium phosphate (TCP) and Ca(OH)2at various temperature(1000 to 1200°C) for 3h with adding 5~20wt% calcium fluoride (CaF2), respectively. The effects of various amount of CaF2on crystallization characteristics of HA-20vol%ZrO2composite were investigated in details. The results show that when small amount of CaF2was added, the reactions of HA with CaF2occurs, which leads to the formation of fluorapatite (FA). With the increasing of the amount of CaF2, the decomposition of HA to β-TCP decreases gradually and the CaZrO3peaks disappear, while t-ZrO2increases because of the formation of thermally stable FHA solid solutions. When the sintered temperature is above 1100°C and the addition of CaF2is about 10wt%, the main phases are FHA and t-ZrO2with a negligible amount of Ca5P8, which suppress the reaction between HA and ZrO2. From SEM, it can be seen that with 10wt% of CaF2addition, the morphology of the composite powder is a mixture of spherical ZrO2particles embedded within agglomerated HA shaped like a small rod.

A novel rapid prototyping technology for glass-alumina functionally gradient materials (G-A FGMs) based on the quick solidification of wax was proposed. The feature of the technology came from its layer-by-layer fabrication of the wax-glass/alumina composite layer. With the help of orthogonal experiment method, the influence of different parameters (sintering temperature, component ratio (the glass and the alumina), and number of layers) on the flexural strength of FGMs was discussed. Optimum conditions obtained from the above experiments were applied to prepare the G-A FGM with three layers. The G-A FGM was analyzed in detail, by observing it under an environmental scanning electron microscope (ESEM) coupled with an X-ray energy dispersive spectrometer (X-EDS). The results of orthogonal experiment show that number of layers is the principal parameter to the flexural strength of FGMs, component ratio is the secondary factor, and sintering temperature may be not an important factor. The special microstructure appears in the cross section of the G-A FGM, observed by ESEM. It is from the X-EDS graph concluded that alumina and glass probably react to form the special microstructure with part removal of wax.

Hydroxyapatite (HA) doped with 3%yttria-stabilized 20wt% zirconia (ZrO2) ceramic were developed in order to produce a porous composite biomaterial by integrating the gel-casting technique with polymer sponge method with improved mechanical strength and controllable porous structure. The pore morphology, size, and distribution of the scaffolds were characterized using an electron microscope. The scaffolds prepared have an open, uniform and interconnected porous structure with a pore size of 300~500m. The porosity of the open pores in the scaffold can be controlled by changing HA-ZrO2 composite concentration and it is between 87%~35%. A compressive strength of 12MPa for HA-ZrO2 porous scaffolds with HA-ZrO2 concentration of 55wt% was achieved, which is comparable to that of cortical bone.

A novel rapid prototyping manufacturing technology for glass-alumina functionally gradient materials (G-A FGMs) based on the quick solidification of wax was proposed. The feature of the technology came from its layer-by-layer fabrication of the wax-glass/alumina composite layer carved in accordance with the shape of each layer of the computer designed model and in situ casting of wax into the carved area. Removal of the wax in the G-A FGMs green body was investigated based on differential scanning calorimetry (DSC) analysis. Sintering properties of the G-A FGMs were discussed. Bending strength of the G-A FGMs was measured by a three-point flexural test. Microstructures of the prepared G-A FGMs were observed using environmental scanning electron microscope (ESEM) and the compositional distribution was determined according to energy dispersive spectrum (EDS). Samples were preliminarily and respectively held at 200°C and 300°C for a long time based on the DSC analysis. The range of the optimal sintering temperature is determined to be from 710°C to 720°C and the holding time is 30min. With the increasing alumina content, the bending strength increases and the maximum bending strength is 67.5MPa. There is no delamination of the G-A FGMs via ESEM. Homogeneous distribution of the ingredient materials is confirmed through EDS.

Numerical modeling on falling of sodiumtetraborate aqueous solution drops as the initiator before the gelation of PVA-TiO2 suspensions was conducted. Effect of time and elevation angle of the PVA-TiO2 suspensions on the falling velocity of the sodiumtetraborate aqueous solution drops was analyzed. An ordinary differential equation was given. Integration of the ordinary differential equation was fulfilled using the fourth-order Runge-Kutta method in Matlab 6.5. From the model, a two-order nonlinear effect of time on the velocity of the drops during falling is determined and the quadratic term -3.408t2 serves as the time dependent air resistance. The component of the falling velocity along the suspensions increases with the increasing of the elevation angle. However, for the component vertical to the suspensions, with elevation angle increasing, it decreases.