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Aluminum-bronze/steel duplex metal has been prepared by aluminum-bronze powder whose compact oxide film was removed by dilute HCl solution before sintering. Scanning electronic microscope (SEM), energy spectrum analysis (EDS), density measurement and compression shear strength test were used to investigate the structure, composition, relative density and bond strength of aluminum-bronze/steel duplex metal. The results show: liquid phase could wet the aluminum-bronze powder washed by acid, improve sintering activity of the powder and increase bond strength of aluminum-bronze/steel interface. The relative density of sintered aluminum-bronze is 99.6%, and shear strength of aluminum-bronze/steel interface is 132.6MPa.

Zinc zeolite-Ce/ TiO₂ antibacterial material was prepared through immersion method with anatase nano- TiO₂ power as main raw materials, zinc zeolite as carrier and cerium ions as doping ions. Its antibacterial function was evaluated by detecting the inhibition zone, the light-catalyzed effect of pure TiO₂ antibacterial material was contrasted with zinc zeolite-Ce/ TiO₂ antibacterial material by using ultraviolet spectrum. The results showed that zinc zeolite-Ce/ TiO₂ antibacterial material had strong bacteriostasis to escherichia coli. It performed best when the diameter of inhibition zone reached to 34.64 mm under the condition of the ratio of nano-TiO₂ to cerous nitrate was 40:1, the reacting time was half an hour, the maturing temperature was 300°Cand pH value was equal to 3.

A new BCB (Bamboo Charcoal Bonded) grinding wheel was developed by bamboo charcoal-phenolic resin composite under vacuum for ELID grinding technology. The pyrolysis behavior of the new bamboo charcoal-phenolic resin material was studied by thermo gravimetric analysis (TGA), and structural characterization of the new material was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD), the friction characteristics was also investigated in this paper.

A high-precise automatic positioning system for data sample of linear time grating sensor is designed. In order to achieve linear time grating sensor of data sample, improve measure work efficiency, an ARM MCU is used as a major chip to control the stepper motor to rotate. In this way, the stepper motor drives the ball screw, the moving probe of linear time grating sensor and reading head of linear grating to move synchronously. A high-precision automatic positioning of the system hardware is designed. In addition, ARM controlling circuits and stepper motor driving circuits are designed. Therefore, the special communication interface is designed for the high-precision automatic positioning system, receiving the feedback signal from time grating sensor, forming a high-precision closed loop control system, and communicating with upper computer by serial. Experiment results prove that the positioning precision of control system can reach 0.1 um.

Aiming at avoiding misregistration in complicated medical image registration based on SURF (Speed-Up Robust Features)-TPS (Thin-Plate Spline), we propose a novel algorithm. This method is based on SURF and human interaction method for feature extraction. Then we improve SURF-TPS and propose an algorithm named TPS-SEMISURF which obtains the deformation field by calculating the Thin-plate spline of the feature points, and finally does the medical image non-rigid registration according to the parameters. Experimental results showed that the proposed method can register medical images effectively. It has a good robustness and owns better precision and rate than traditional algorithm.

A new kind of adsorbent is prepared in the present study, which is expected to capture NOx with high efficiency. NaOH, Ca(OH)2, carbide slag, diatomite, activated alumina are chosen as the major material with a small amount of surfactants and dispersants as the additive. Different recipes were characterized by SEM and N2 adsorption-desorption method. The result showed that the optimum adsorbent has the largest surface area of 95.67m2/g which is Ca(OH)2: NaOH: activated alumina=4:1:1. The test on removal of NOx is conducted. The result showed that the adsorbent is capable of removal efficiency exceeding 98% in 10minutes.

This paper is about a kind of instrument which can detect the fault object by acoustic sensor detecting the object Surface acoustic signals, through the analysis of the acoustic signal of the intensity and frequency content, so determining the object if abnormal conditions occur. Design by using Piezoelectricity material as the sensing head, the signal processing circuit is based on SH79F32 microcontroller as the core, the single-chip microcomputer, integration with ADC, the analog signal from the sensor to convert them into digital signals, in the procedure, carries on processing to the signal frequency components, filter out low-frequency components, acoustic signal was finally measured on a screen display. including hardware design, production, processing, software programming, to obtain the acoustic fault detector, and to test its performance, results show successful.

Designed for 6500V 4H-SiC JBS diodes, a highly-efficient termination structure of a non-uniform multiple floating field limiting rings (MFFLR) featuring with a non-uniform ring spacing and a multiple region division is studied and purposed. For each region, ring spacing is modulated independently by a multiplication factor and a linear increment factor. The non-uniform MFFLR structure is simulated and optimized for a better electric field distribution and a higher breakdown voltage. Based on the simulation results, 4H-SiC JBS diodes with the optimized non-uniform termination designs are fabricated. Experimental results show that the SiC JBS diode with optimized non-uniform MFFLR termination structure can achieve a breakdown voltage of up to 7800 V, and its termination efficiency is about 94% of an ideal parallel-plane junction’s. Our results demonstrate that the optimized non-uniform MFFLR termination structure is capable for SiC JBS diodes with breakdown voltage of 6500V and above. Our results can provide a valuable design methodology of edge termination structures for other high-voltage SiC devices.

A non-contact Fourier-domain optical coherence creep tomography (OCCT) is developed and employed in real-time non-contact creep measurement. Experiments on thermal deformation were carried out by using the self-developed OCCT to measure a high-temperature structure. In the OCCT system, a high-performance spectrometer, and a thermal light are, respectively, employed as the detector and the light source. Due to the broadband of the spectrometer and light source, the system provided high robust performance with an excellent deformation measurement resolution of sub-millimeter scale. Due to the energy leakage effect of FFT, a spectrum correction technique was employed to enhance the resolution of the OCCT system. From the experimental results, the self-developed OCCT has great potential applications in non-contact real-time creep measurement of high-temperature structures.

In this study, the grinding force variation mechanism in ultrasonic assisted grinding (UAG) of SiC ceramic is investigated by simulation method using a single diamond abrasive grain scratching. In simulation, the workpiece is modeled by smoothed particle hydrodynamic (SPH) method while the abrasive grain is modeled by finite element method (FEM). To reliably predict the grinding forces in UAG, an analytical model of average undeformed chip thickness h_a is established. Grinding forces under different grinding parameters, i.e., depth of cut, and different ultrasonic vibration amplitudes are calculated by setting average undeformed chip thickness h_a as scratching depth during SPH simulation process. The simulation results indicate that the normal force in UAG is reduced by about 20%, while the tangential force decreases up to 30% compared with those in conventional grinding (CG). The influences of grinding parameters and ultrasonic vibration on grinding forces will be investigated and the preliminary explanations will be presented.