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To grind fused silica in ductile mode, it was proposed to repair surface and subsurface micro cracks of fused silica by CO2 laser irradiation. However, excessive residual stress remains on the surface because the melt fused silica on the surface quenches in air. It causes the critical depth of cut for ductile grinding fused silica to be smaller than 0.2μm. To investigate the distribution of the residual stress and look for an optimal manner of irradiation to control residual tensile stress, a numerical model of was built for simulating the dynamic behavior of fused silica when irradiated by CO2 laser. Laser energy absorption, heat transmission, viscoelastic behavior of fused silica and thermally induced stress were considered in the numerical simulation. The results show how the residual stress is formed and distributed. We found that an appropriate control of the temperature field as a function of time and position in the laser process is the key to reduce the residual stress. Therefore, three kinds of processes were proposed to reduce residual tensile stress on the surface of fused silica introduced by laser irradiation. The residual stress distributions of these three processes were compared by numerical analysis to decide a better method of laser irradiation.

Dispersion of carbon nanotubes in water largely determines the excellent properties of carbon nanotubes can be fully exhibited in the composite material. Summarizes the characteristics of all kinds of surface active agent, select several can represent various types of surfactant reagents to test and comparing the several kinds of surfactants on the dispersion of carbon nanotubes, and focus on the effects of polyvinylpyrrolidone special molecular structure on the surface of the carbon nanotubes.

In this paper, multiple actively-controlled fans generate outdoor near-surface airflow in a wind tunnel with once-through openings. The wind tunnel system consists of 6 groups of fans installed on rotatable plates in a rectangular inlet. We use a stochastic strategy to control the fans and the rotatable plates to regulate wind speed and direction that fluctuate according to the pattern of outdoor near-surface airflow. We utilize the statistics and multi-scale methods to analyze the effectiveness of the strategy for simulating the outdoor near-surface airflow. We provide comparison studies on the multi-scale entropy of wind speed, wind stability, and the standard deviation of directions between out-door wind and the tunnel generated wind. Results show that a flow field akin to the near-surface airflow in outdoor environments can be produced by the wind tunnel using the stochastic control strategy, which can be considered as a reliable experiment environment for gas pollution source localization research in outdoor near-surface breeze conditions.

A technology conception of producing filled metal particles which use steel scraps of steelworks as the main raw materials for welding was proposed in this paper. It provides a new resource for raw materials which are used to process welding material and the steel scraps are used sufficiently, reasonably and in high value-added at the same time. According to the wearing conditions of loader when it exploits and loads the river sand, the Fe-Cr-C alloy particles were designed. The technology of medium frequency induction furnace - centrifugal atomizer was used to get the alloy particles in 0.1~5.0mm diameter. Melt alloy particles by submerged arc welding and study the microstructure and properties of the deposited metal. Engineering application tests were also carried out and yield highly desirable results.

In this paper, a type of high-deposition-rate, low-dilution-rate and wide-welding-bead flux-cored strip which is easy to realize automatic surfacing was designed. Considering the working condition of high temperature and abrasive wear in the iron and steel industry, a kind of high-chromium iron surfacing flux-cored strip was designed. The effect of alloy elements on the microstructure and property abrasive wear resistance of deposited metal was investigated. The abrasion and heat resistant plate deposited by the flux-cored strip was carried out on raw material transport system in steel enterprises. The service life was significantly improved and the examination and repair time is reduced.

In this paper, a type of high efficient ultra-thick high-chromium cast iron surfacing flux-cored wire of a diameter of 6mm is designed to solve the technological problem that the processing property of ultra-thick flux-cored wire can not meet the welding requirement, and “inter twist connection” and “inner wire” technologies were adopted. The effect of alloying elements Cr and C in the powder on the microstructure and property of deposited metal was researched. The results showed that when Cr content is 39% and C content is 5.7% in the powder, the microstructure of deposited metal is nearly eutectic, of which the hardness and wear resistance are higher. The test of engineering application of surfacing was carried out on bucket in wheel loader. It is proved that the wear-resisting property and the service life of the bucket can be significantly improved.

The user interface made of a LCD (liquid crystal display) screen and a touch screen based on LPC2138 is presented in this paper. The hardware design of the LCD and the touch screen is introduced and the software flow of the LCD and the touch screen is also described in this paper. And this paper proposes the synchronization algorithm which can achieve the LCD and the touch screen point by point with high accuracy and great reliability. On the basis of analyzing the principle of the embedded touch panel system, the working principle and control method of the dedicated controller DV320240GB touch screen are analyzed. The method for obtaining the coordinates of the touch screen and the synchronization algorithm of the LCD display are proposed to improve the efficiency of the touch screen and the LCD. The above-mentioned design has been successfully applied in ESR (erythrocyte sedimentation rate) detection system.

Nano titanium dioxide particles were synthesized by drolysis of TiCl4 through the phase thransfer and pH of the system is adjusted by Na2CO3 At the same time, the particles were characterized by the Transmission Electronic Microscope(TEM) and X-Ray Diffraction(XRD).As the result, it is shown that the TiCl4 solution was transformed from n-octyl alcohol to deionized water phase and reacted with the deionized water at 55°C, the precursors of nano-TiO2—Ti(OH)4 was dried for 6 hours under vacuum at 70°C,then calcined 3 hours in muffle furnace at 400°C.At last, the TiO2 nanoparticles which is uniform distribution, weak agglomeration was synthesized. In addition, wastewater in paper mill treatment with TiO2 nanoparticles was studied by experiment. It is shown that suspended substance and COD in wastewater were brought dwon largely. The mechenism that wastewater was treated is disscussed.