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In this investigation, micro crystalline diamond (MCD) and nanocrystalline diamond (NCD) films are deposited on cemented carbide (WC-Co) balls by hot filament chemical vapor deposition (HFCVD) technique. After deposition, MCD and NCD films are characterized by field emission scanning electron microscopy (FESEM) and Raman spectroscopy. Then frictional tests are carried out between CVD diamond coated balls and graphite. The results show that the MCD-graphite and NCD-graphite tribo-pairs exhibit comparable frictional coefficients, while the wear rate of graphite in MCD-graphite working pair is much higher than that of graphite in NCD-graphite working pair. Furthermore, the element oxygen is detected in the wear groove of graphite, suggesting the oxycarbide of working materials at the increased temperature due to the heat generated from the mechanical friction.

This Paper has analyzed the relationship between the generation of multiple piezoelectric effects and boundary conditions of piezoelectrics and the experiments have studied tertiary piezoelectric effect of piezoelectric quartz which is applied extensively in engineering practice. We processed our experiment by piezoelectric quartz crystal unit made by two pieces of X-cut piezoelectric quartz, parallel connected it to a capacitor with the equivalent capacitance of about 1,000 times of that of piezoelectric quartz crystal unit and then got the result of pure primary piezoelectric effect excluding tertiary induced effect; then compared it with conventional primary piezoelectric effect and concluded that tertiary piezoelectric effect of piezoelectric quartz is about 1.7% of primary piezoelectric effect; thus quantified longitudinally tertiary piezoelectric effect of piezoelectric quartz crystal, concluded that piezoelectric coefficient of tertiary effect of X-cut piezoelectric quartz is about 0.04 pC/N by experiment and got relative uncertainty and standard uncertainty of the results by such experiment methods respectively as 9.49×10-3and 1.37×10-2. This study on tertiary piezoelectric effect has provided a new approach for improving precision and sensitivity of piezoelectric sensors.

Lane changing is the common behavior when cars are running. It will produce traffic conflict, reduce the efficiency of road system, and lead to malignant traffic accidents. Based on the analysis and evaluation of circular, cosine type, constant lane migration type and ladder lane transformation type, considering the driver behavior, vehicles control and dynamic constraints and thinking the obstacles as an infinite number of circles to idealize them, this paper establishes polynomial in horizontal and vertical directions respectively to indicate the position of vehicle, obtains the lane changing trajectory by testing whether the distance between circles meet some conditions, builds polynomial for the safe lane changing trajectory and real-time dynamic optimal distances between vehicles, and then utilize the MATLAB as the simulation tool to make experiments in various cases. Simulations and experimental results show that the method given in this paper to calculate the vehicle safety lane changing trajectory in the case of high-speed vehicle is feasible, effective and can give quickly safety lane changing distance.

protein was extracted from Antarctic krill (AK), then blended with sodium alginate (SA) , prepare the spinning solution, the rheological properties of spinning solution were studied by Brookfield DV-C digital viscosimeter. AKP/SA fibers were prepared via wet spinning with CaCl2 and PEG as coagulator .The morphology, tensile strength and thermal property of AKP/SA fibers were characterized by polarized light microscopy, monofilament strength tester and thermal gravimetric analysis (TGA) instrument. The result shows that the shear viscosities of spinning solution decrease with the increasing of shear rate and decreasing of concentration. the optimal Preparation Process of AKP/SA fibers were 5% concentration of SA, proportion of 1: 9 for AKP solution to SA solution, and proportion of 5:1 for CaCl2 to PEG. The cross-section of AKP/SA fiber is a jagged shape. Thermal property of AKP/SA fibers is similar to SA fibers.

For analyzing the effects of specimen-dimension on dynamic behaviors of fiber-reinforced composites, 4 kinds of CFRP specimens for different dimension were designed and made. The compressive loading tests were conducted by Ф 37mm split Hopkinson pressure bar (SHPB) system. The results show that the dynamic compression effects of specimen-dimension were exposed. An amount of Fiber-reinforced units inside the compressed area of the fiber-reinforced composites, then the experimental data are veracious for the material.

Stress of pressurizer surge line due to stratification is calculated with the help of finite analysis software, using both simplified temperature distribution and the temperature fields of CFD simulation result. Stress and displacement of pressurizer surge line are achieved. Evaluation of the fatigue life reduction due to stratification is done by using modified fatigue design curve and referring to environmental fatigue factor. The conclusions here indicate that it can’t be neglected that stratification reduces the fatigue life of pressurizer surge line.

Intelligent Transportation System (ITS) is a new industry and development greatly in recent years. The advanced electro-communication and computer technology combines detection, control, active warning and other information means. It provides a great guarantee for improving traffic safety and high efficiency. This paper puts forward the traffic rate-limiting sign and Lane Mark recognition method. In this study, four steps are applied to recognize a traffic and Lane Mark sign in an image. The first step, we transform the color space of image from RGB into HIS. Then the image blended HIS and RGB information is segmented. The third step, the text restrain and eliminate the isolated noise point based on eight-neighborhood. Finally, the traffic speed-limit sign and Lane Mark is recognized with template match. Our experiment results, in the out door, show that the method mentioned in the paper is useful and effective.

This article introduces the classification and composition of Grid-connected Photovoltaic Power System, and the research status of its nonlinear behavior. In the Photovoltaic Power System, photovoltaic array, DC/DC converter, DC/AC inverter and nonlinear load will appear lots of nonlinear dynamic behavior such as bifurcation and chaos phenomena. The paper elaborates the DC/DC converter and DC/AC inverter in the Photovoltaic Power System, and analyses their nonlinear phenomena.

In this work, Chromium (Cr(III)) conversion coatings on Al 6063 alloy was prepared using trivalent-chrome compound (KCr(SO4)2) and H3PO4. The influence of five variables (i.e. deposition temperature, time, bath pH, and concentrations of (Cr(III)) compound (KCr(SO4)2) and H3PO4) on the preparation of (Cr(III)) coating on Al 6063 alloy was investigated using polarization curve in 3.5 wt% NaCl solution. The parameters of polarization curves were obtained from the extrapolation of anodic and cathodic Tafel lines. The optimum chemical passivation parameters of the chromium (Cr((III)) conversion coatings on the 6063 Al surface were obtained in this paper The results show the chromium (Cr(III)) conversion coatings formed under the optimal range present better corrosion resistance than those under the other conditions. Proper mechanisms were proposed to explain the above electrochemical behavior for the five treated conditions.

This article study the connecting performance of the corrosion high-strength bolts. According to the experiment of anti-slippery,the essay investigate anti-slippery coefficient, sliding load and ultimate load affected by the the extent of corrosion.The articl aslo study about the load-displacement cure of high-strength bolts connecting,which study The difference of the relation between load and displacement in each stages,cause by the whether the high-strength is corrosion.