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The double spherical seismic isolation (DSSI for short) bearing has been adopted in seismic design of several important engineering projects since developed recently. It was used generally as fixed bearings in a continuous girder bridge in these projects, and only a few fixed piers, usually just one fixed pier would transmit the horizontal earthquake action to the foundation, which is uneconomical and results in the much larger seismic risk in the longitudinal direction of a continuous girder bridge than that in the transverse direction. In order to share the earthquake effect with all the piers and avoid relative vertical displacement among all the bearings under the normal traffic conditions, a new seismic design method of continuous girder bridges is introduced. The configuration and working mechanism of two kinds of DSSI bearings used to make the new seismic design possible are introduced. It’s shown that the method is preferable for the seismic design of continuous girder bridges by a numerical seismic analysis with a four-span continuous girder bridge.

Anodic oxidation in situ preparation of titanium matrix TiO2 nanotube and optimize the preparation process parameters. With the help of X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) technology we characterized the light catalyst that we have prepared. By oxidation degrading methylene blue, we tested its light catalytic activity. The result showed that the TiO2 nanotube maded at 20 V anodizing voltage, ionic liquids (2 ml), ammonium fluoride (0.684 g), ethylene glycol volume (200 ml) and water volume (6 ml)after 20 h, after dried for 30 min under 105 oC and annealed for 1 h under 500 oC in air became anatase phase, and the ratio of rutile phase is very low. The TiO2 nanotube arrays we made under the above condition for the degradation of methylene blue are good. The average diameter of a nanotube is about 90 nm, and the average thickness of a nanotube’s rampart is about 10 nm.

In order to study the effect of rock fracture distributions on stability of tunnel, the effect of joints with different strike dip, the size and density was considered by using probability and statistics method. Based on the Monte Carlo random simulation, the statistical network model of 2D jointed rockmass was established to describe and characterize jointed rock mass. On the basis of this, the numerical code RFPA2D is employed to analyze effect of fracture dip angle on the tunnel stability. Numerical results show that the fracture distribution has a little effect on tunnels failure mechanism and failure type of tunnel because the failure of tunnel in the jointed rockmass is similar to the one without joints and fissures. However with the change of the fracture dip angle, the loading capacity of the tunnel in the jointed rockmass varies accordingly.

In this paper, the property of common biomass-rice husk was compared with that of coal. The combustion characteristics of rice husk were investigated by Thermogravimetry (TG) method, and the barriers for biomass fuels utilization as an alternative fuel to manufacture artificial aggregates were also analyzed. The key techniques of using biomass as an alternative fuel in light-weight aggregate production, such as preprocessing of the biomass feedstock, proper design of combustion system for biomass fuel and control of sintering process were proposed. Properties of artificial aggregates sintered by biomass fuel were also studied according to GB/T 17421.2-2010 test method, and the test results showed that all the properties meet the requirement of national standard.

Pressure vessel is widely used in the industrial engineering. Many materials in pressure vessel are inflammable and explosive dangerous goods. If the accident happens, great harm will be done to the lives and properties of people. Some common methods for studying pressure vessel have obvious drawbacks. 3D laser scanning method uses non-contact measuring method and can directly obtain the point cloud data of the mass surface which can be used to reconstruct any convex surface. According to the advantages of 3D laser scanning method, in this paper, it is introduced to measure the dimensions of flanges in pressure vessel. The experimental results obtained have little errors, which certify that 3D laser scanning method can be used to measure the dimensions of flanges and further study the characteristics of pressure vessel.

Remote control and fault diagnosis of ultrahigh speeding grinding is studied, which is based on the theory of rough set. Knowledge acquisition and reduction rule of fault diagnosis, realization method of remote control for ultrahigh speed grinding are studied, diagnosis model is established. Based on the theoretical research and ultrahigh speed grinder with a linear speed of 250 m/s, the remote control and fault diagnosis system of ultrahigh speed grinding is developed. Results of the system running show that the environment is improved, the mental pressure of workers is relieved and the efficiency is improved. At the same time, it proves that the ability to diagnosis and the accuracy of diagnosis for the ultrahigh speed grinding are improved and the time for diagnosis is shortened by applying rough set.

A novel structure for CMOS four-quadrant analog multiplier is presented. The multiplier is based on the square law of MOSFET. To enlarge the input impedance and improve the linearity, CMOS source coupled pair was employed. Also active attenuator was used to enhance the input range. Compared with the traditional multipliers based on Gilbert cell, the proposed circuit features high linearity, high input range. Circuit simulation using HSPICE with 0.5μm CMOS technology shows that under ±2.5V supply the proposed multiplier provides linear range of more than 50% of the voltage supply, THD is 0.3% at 100kHz and 0.8% at 1MHz, -3dB bandwidth is 2.5MHz, and the power consumption is 5mW.

The sub-rapidly solidified Au-20Sn eutectic alloys were prepared by four different solidification pathways, such as, graphite mold conventional casting, graphite mold injection casting, copper mold injection casting, and water-cooled copper mold suction casting. The precipitating sequences of competing primary phases of sub-rapidly solidified Au-20Sn alloys with four different cooling rates were investigated. The results show that phase selection process is related to the cooling rates during sub-rapid solidification process. The primary ζ'-Au₅Sn phase with developed dendrites precipitate at low cooling rate (2.4×10−4.2×10² K/min) and the morphologies of the primary ζ'-Au₅Sn change to rosette-like at higher cooling rate (9.0×10³ K/min). While the cooling rate reaches to 3.5×10⁴ K/min, the primary ζ'-Au₅Sn phase can be suppressed but δ-AuSn phase will precipitate prior to the ζ'-Au₅Sn phase. On the basis of the classical nucleation theory and transient nucleation theory, the process of competitive nucleation between the ζ'-Au₅Sn phase and the δ-AuSn phase were analyzed for sub-rapid solidified Au-20Sn alloy. The theoretical calculations are consistent with the experimental investigations.

The paper uses the preprocessor of ANSYS to generate the model of 3D entity and mesh generation on WW0.8/10 air compressor crankshaft. Mesh generators are transferred into data that will be used in finite element analysis. Passing by dealing with force and commitment, it calculates the forces of pressure working conditions of crankshaft. They are used in stress analysis. The stress data is calculated from the calculator of ANSYS. The static load safe coefficient and the fatigue safe coefficient of the crankshaft are tested from known stress. The result provides a high reference value for the optimization improvement of the crankshaft.