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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.

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.

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.

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.

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.