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Chemical mechanical polishing (CMP) is the effective technology which obtains high accuracy surface of hard disk substrate with nickel-phosphorus (Ni-P) coating. The slurry is significant factor in hard disk substrate CMP. Colloidal silica-based alkaline slurry was prepared based on negative pressure vortex method. The effects of slurry parameters such as abrasive concentration, organic alkali concentration and oxidant concentration on material removal rate and surface characteristics were investigated. The experimental result indicated that the abrasive concentration was 20wt%, the slurry pH value was 11.2, the oxidant concentration was 15ml/L, improved surface roughness and polishing efficiency of hard disk substrates, a smooth surface was obtained and micro scratches could hardly be observed.

In this paper the TiNi/Ti2Ni composite powders has been synthesized by the chemical reaction between titanium and nickel powders in high temperature molten salts. Results of the differential scanning calorimetry (DSC) confirmed the reverse martensitic transformation of the prepared TiNi powder in the TiNi/Ti2Ni composite powders. The backscatter electron images of the scanning microscopy (SEM) of the end-products before washing by distilled water showed that the synthesized TiNi/Ti2Ni composite particles were captured by the molten salts, which revealed the mechanism of the chemical reaction in molten salt.

SNCR (Selective Non Catalytic Reduction) system is proposed, with 40% methylamine aqueous solution as reducing agent to reduce NOx in diesel exhaust gas. The effect of injection position and volume on the reduction efficiency through the test bench is systematically researched. A three-dimensional model of a full-sized diesel SNCR system generated by CFD software FIRE is used to investigate the reduction efficiency under different temperatures. The simulated results have a good agreement with the test results, and it can be used to optimize SNCR system. The results can indicate the practical application of this technology.

The main failure modes of starter battery are discussed, the causes resulting in the premature failure of starter VRLA(valve-regulated lead-acid) battery are analyzed and corresponding countermeasures against failure of starter battery are presented. It proves to be of practical help.

An efficient Integrated Bandwidth Allocation Scheme (IBAS) is proposed to serve the lower priority requests can be early assigned the bandwidth without waiting too long. These will speed up the channel capture by priority data to support the multimedia traffic over DOCSIS-compliant cable networks. The efficiency of IBAS is investigated by simulations. The results show that by adopting IBAS can not only shorten the collision period but also minimize the average request delay of lower priority requests. Performance has been improved in throughput and delay compares to the current DOCSIS specifications.

A newly constrained multi-objective differential evolution optimization technique (CMODE) for security constrained economic/environmental dispatch (EED) was proposed. The proposed CMODE evolved a constrained multi-objective version of differential evolution (DE) by employing the traditional multi-objective differential evolution (DEMO) and constrain handle technique to balance the search between feasible region and infeasible region. The proposed CMODE method had been applied to solve the security constrained EED problem. Experiments had been carried on a standard test system. The results demonstrate the high efficiency of the proposed method to solve security constrained EED problem, and the necessary of taking security constrains into consideration.

The microstructure and tensile properties at room temperature of as-cast, solution-treated and aged samples of a Mg-5Sn-5Zn (wt%) alloy are investigated. The microstructure of the as-cast sample consists of -Mg primary, Mg-MgZn eutectic, divorced eutectic Mg2Sn and secondary precipitation Mg2Sn. After solution treatment, all the MgZn particles and the majority of Mg2Sn phases are dissolved into the matrix and the tensile strength and the elongation of the alloy increase obviously. During aging process many fine particles precipitate which result in the improvement of the yield strength.

In order to ensure the safety of the curved girder bridge operations, the actual testing is necessary to determine the impact of various factors on the horizontal offset of the bridge bearing against bearing defects. In this paper, finite element analysis with Midas/Civil is applied to each factor separately to get the spherical bearing offset of various factors which compared with the actual displacement analysis, and get the impact the bridge itself gravity, the vehicle load generated by the centrifugal force and the temperature load to the spherical bearing horizontal offset. The analysis results show that the main reason of the spherical bearings horizontal offset is climb shift of the bridge in temperature load. On this account, make effective measures for the protection and repair of bridge to ensure the safety of the bridge operations.

Custom tooling is an effective method to improve surface roughness, geometrical accuracy, machining efficiency, and consequently the core competitiveness of the final products in very complicated freeform creation and micro/nano machining, such as the propeller, blisk and ductile-mode machining of hard and brittle materials. However, commercially available CAM systems have limitations in generating CNC programs for these customized tools due to considerations for special custom tool fabrication processes. Therefore unique CAM system is needed and consequently dedicated CAD sub-system is the prerequisite for such CAM system. In this paper, the dedicated CAD sub-system design is studied to extend the authors’ previous study. The characteristics of customized tools are summarized and analyzed. Then, the functions for the dedicated CAD sub-system are analyzed and defined. Finally, the system is designed and developed by using VC++, Open CASCADE, and ActiveX Data Object techniques.

This paper studied the borehole stability in Liulin bituminous core reservoirs during under-balanced drilling. The equivalent depth method was applied to study the formation pore pressure. The floor drain test method was applied to study the ground stress. Core strength experiments combined with logging data were used in the establishment of core strength predicting model. Mechanics analysis model was founded to study the borehole stability in the core reservoir. According to the studying and analyzing results, the under-balance drilling in Liulin coal reservoirs enjoys good borehole stability.