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In this paper, we introduce the entropy theory and energy theory into the research of analyzing the crack open and propagation. Regulation, analyzing the factors that affect fractured crack propagation, and establishing the method of researching fractured crack propagation using entropy theory. Transforming the stress factor that affect crack propagation into entropy value, and on that basis we established the entropy variation equation for calculating the crack open, and obtained the new criterion and model for calculating fracturing crack open. Obtaining a new method for describing crack propagation regulation from the entropy aspect. Revealing the nature of crack open, propagation and close from microscope.

The texture feature and grain refinement effect of Al-5Ti-C alloy on pure aluminum were analyzed and its attenuation mechanism was discussed by using X-ray diffraction (XRD), scanning electron microscopy (SEM), optical microscopy (OM) and other experimental methods.The results show that: Al-5Ti-C alloy is composed of Al, TiAl₃ and TiC. Al-5Ti-C alloy has a good grain refining capacity for commercially pure aluminum. During the heat preservation process, due to precipitation of titanium compound in the aluminum melt, refinement effect of Al-Ti-C alloy is declined.

In this research, an experiment was designed to study the capillary absorption of fly ash concretes. In order to understand the essence of capillary absorption, samples of fly ash concrete with different heights at different curing ages were tested in this experiment. It is found that the samples tested at 7d and 28d had the same sorptivity. And the height of the samples has no influence on the capillary absorption.

Catalytic hydrolysis decomposition of dichlorodifluoromethane (CCl₂F₂) in the presence of water vapor and oxygen was studied over solid acid MoO₃/ZrO₂ using a fixed-bed reactor. The CCl₂F₂ adsorption was multilayer chemical adsorption and its process was corresponding with Freundlich model. Its heat was from 56.3 to 73.2 KJ.mol^-1, and it was exothermic reaction and chemical adsorption.

With the promotion of building energy conservation, many residential areas are closely link with energy saving in design phase, and natural ventilation becomes the key to reduce building energy consumption. Thus, house design and building distribution of residential district is particularly important. Computational fluid dynamics (CFD) get rapid development in recent 20 years, especially in architectural design. This text established a model of part of a residential district in Zhuzhou based upon ANSYS FLUENT CFD software, and used numerical simulation method to simulate the condition of indoor natural ventilation under typical summer climate when the doors and windows of buildings were opened. The distribution regularities of indoor velocity field and pressure field and etc have been gotten. These data provide a theoretical basis to evaluate the building distribution of residential area.

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.

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.