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A new kind of kinetic hydrate inhibitor (KHI) named KL-1 as the ramification of poly (N-vinyl caprolactam) (PVCap), was synthesized successfully by use of precipitation polymerization. The hydrate inhibition performance of KL-1 was assessed in a high pressure sapphire cell, and the onset time of hydrate formation and maximum subcooling were determined by the visual observation method and compared with the commercial KHIs, including Inhibex 501 and VC-713. Meanwhile, the synergic effect between ethanol and KL-1 developed was also studied in this work. The experimental results show that the onset time of KL-1 measured increases with the increase of the dosage and decrease of subcooling. Compared with the system without kinetic hydrate inhibitor, the morphological behavior of hydrate crystals in the systems containing KL-1 is different, and the hydrate crystals only grow to the gas phase with the hydrate formation. Additionally, based on the measurement of inhibition time, the inhibition performance of KL-1 is superior to Inhibex 501 and VC-713, and shows higher maximum subcooling at the similar conditions. Finally, we also demonstrated that ethanol can be used as synergist to improve the performance of KL-1 remarkably at suitable dosage.

0.15 wt. % Ti-microalloyed Co-28.5Cr-5.9Mo-0.27C alloy has been developed by examining the effect of solution and aging treatment on microstructure, mechanical and corrosion properties. The results showed that elongation of the cast specimen were lower than 8%, while reached 18% after solution-treated at 1220 °C for 4 h. Phase transformation from austenite to martensite was observed after aging at 800°C and the amount of transformed martensite increased with aging time. Polarization tests of the samples after solution and aging treatment were carried out in physiological saline at 37 °C, which showed a stable passive film formed on the surface and no apparent pitting phenomenon occurred on the specimens, which indicated that heat treatment has not significant influence on the corrosion resistance of Co-Cr-Mo-0.27C-0.15Ti alloy.

In the context of globalization, it should be have more advantages if ports join in competition in the form of group. But the port classification is not clear, so the necessary of analyzing the ports’s classification in the Bohai ring area is carried out. Cluster analysis was applied in classifying the ten ports of Bohai ring area and provided the basis for the classification and port layout . According to the clustering result, 10 ports are divided into four categories.

Based on MSC.ADAMS, the virtual prototype of two design schemes is built in the timing belt of LED placement machine, and simulation analysis of two design schemes of timing belt module is made. Simulation results show that, the timing belt model in the motor-middle-driven design is better than the motor-side-driven model in the synchronization performance. Based on the method, the performance of timing belt can be obtained before the prototype manufacturing, and the result can guide the timing belt design in LED placement machine.

With the continuous development of LED industry, speed and accuracy requirements of LED packaging equipment is more and more high. To further improve the operation speed, it is very important to improve the stability of the positioning platform. Based on MSC.ADAMS(Automatic Dynamic Analysis of Mechanical Systems),the dynamics simulation model of the positioning platform in LED packaging equipment is established, and the effects of the assembly precision is researched on the machine performance. The method provides the theoretical basis and practical guidance for LED assembly process, and thereby can improve the operation speed and stability of the packaging equipment.

In the processing of the mold texture, the traditional chemical etching exits the shortcomings of the pollution and the long processing cycle. This article will introduce 3D laser processing technology to the mold industry, based on the laser etching principle on the metal surface, etch processing can be made in the mold surface. Through theoretical derivation from the 3D laser scanning optical system, the 3D laser scanning hardware system is structured to apply in the mold cavity texturing, the control algorithm has been studied, and finally in the developed laser-etch machine the texturing experimental is performed on the injection molds.

The extraction kinetics and mechanism of La (III) by P204-kerosine from phosphoric acid were investigated by constant interfacial cell with laminar flow. The effects of stirring speed, temperature, specific interface area on extraction rate were studied. The results indicated that a plateau region is appeared at the stirring speed of over 115r/min. The extraction apparent activation energy was calculated to be-13.40kJ/mol and the extraction process is controlled by a mixed mechanism of diffusion and chemical reaction. The rate equation of extraction was deduced. Under conditions of 25°C and interfacial area 19.64cm2, the extraction rate constant was 2.08×10-6 m·s-1·. Through the derivation of the reaction mechanism the reaction zone is at the liquid-liquid interface.

In the paper, the injection process of mold sleeve is simulated with Moldflow software, and the filling time, cavitation, weld, and causes warping are analyzed. The warping effects on the workpiece surface quality. Moldflow software can optimize gating system and shorten the fill time, improve the quality of plastic surface, reduce the number of repair mode, and shorten the product development cycle.

At present, high speed machining (HSM) features in high efficiency, high precision, high flexibility and high quality. HSM technology involves many factors, including cutting mechanisms, machining performance, tool path and other aspects. The key techniques on HSM such as linear interpolation, circular interpolation, cubic B-spline curve interpolation, non-uniform rational B-spline (NURBS) curve interpolation and their respective characteristics are paid more attention and expatiated.

High speed machining (HSM) features in high efficiency, high precision, high flexibility and high quality. The key techniques on HSM such as linear interpolation, circular interpolation, cubic B-spline curve interpolation, non-uniform rational B-spline (NURBS) curve interpolation and their respective characteristics are paid more attention and expatiated. Circle arcs are approximated by using intersecting polygons instead of general inscribed polygons. NURBS interpolation algorithms can reduce feedrate fluctuation and improve machining accuracy.

The placement machine was simulated by multidisciplinary co-simulation method in various working conditions, and its dynamic accuracy was studied by simulation. According to the structure form of the placement machine, the virtual prototype for co-simulation was built. The impact of all sorts of parameters on the system dynamic accuracy was simulated including the stiffness and damping of the slider and the shaft coupling, the friction coefficient and the mass distribution etc. The result shows this method is able to predict the dynamic performance and the control margin of the whole machine, instruct the design optimization and the selection, and provide the good design thought and direction for the matching design of the machinery and controlling system.

The development of PCB CNC drilling machine is toward high-precision and high-speed, and the impact of the join cannot be ignored. Based on the finite element software, the finite element model of the drilling shaft system including the joins is established; the modal analysis and the frequency response analysis are performed on the drilling shaft system, the natural frequencies and mode shapes are obtained; the effect of the different parameters on the natural frequencies is analyzed, and the basic data can be obtained from the analysis.

In the manufacturing industry, high speed milling plays a very important role. The paper introduced a number of essential core component of the key technologies in high speed machining center such as powerful computer numerical control systems, motion control card, post –processing method, processed trajectory control technology (Look Ahead) and high speed processing of programming. The speed control, post processing and look-ahead control are focused on considering, and the corresponding improved methods are brought forward.

Based on multi-body dynamics, the virtual prototype model of the tape feeder is set up, and the impact of the external torque and the friction coefficient on the whole system is analyzed. Simulation results show that the external torque has great influence on the required motor torque: when the external torque increases from 50N.mm to 200N.mm, the required motor torque increases from 75.217N.mm to 223.98N.mm. The friction damping also has great influence on the motor torque: when the dynamic friction coefficient increases from 0.001 to 0.009 and the static friction coefficient increases from 0.003 to 0.011, the required motor torque increases from 106.92N.mm to 158.81 N.mm.