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The blade is one of the key part of aero engine because its shape precision and surface quality significantly influence the performance, efficiency and reliability of the engine. The blade surface is generally obtained by precision finishing process, which is a repeated work of profile error measurement, profile error calculation and error correction manufacturing. For profile error calculation, the matching of measurement points and ideal blade surface must be firstly performed. However there is few detailed work reported on matching algorithm. In this paper, a new matching algorithm for profile error calculation was proposed. Firstly, the coarse matching method based on characteristics of blade section curves between measurement points and its corresponding ideal section curve was studied. Then the Sigular Value Decomposition (SVD)-Iterative Closest Point (ICP) precision matching method was adopted to improve the matching precision. After that, the weight calculation method was applied to balance the profile errors among different section curves. Simulation work was performed to validate the proposed matching algorithm. Results shows that micrometer-order matching accuracy of the blade section curves could be obtained through the above-mentioned three matching steps.

A middle grade siliceous phosphorite from Yunnan province was selected to treat Cd2+ bearing aqueous solutions. The siliceous phosphorite was tested by X-ray fluorescence spectrometer, X-ray diffraction, infrared spectrometer and scanning electron microscopy. The results present that the valuable mineral is nanostructured carbonated fluorapatite and the major gangue mineral is quartz. The amount of Cd2+ sorbed by the siliceous phosphorite tends to increase with the increase of initial pH or the initial Cd2+ concentration of the simulated waste water. The reaction process of Cd2+ removal from aqueous solutions is highly fitted with the pseudo-second order kinetic model. The results indicate that nanostructured carbonated fluorapatite bearing siliceous phosphorite can effectively immobilize aqueous Cd2+.

This paper reports a novel coprecipitation process for the preparation of strontium-barium hydroxyapatite [Sr5-xBax(PO4)3OH]. Strontium nitrate, barium nitrate and phosphoric acid were dissolved in water to form a homogeneous Sr-Ba-P aqueous solution. The samples were characterized by powder X ray diffraction, Fourier transformed infrared spectroscopy and scanning electron microscopy. The results showed that the barium phosphate [Ba3(PO4)2] phase appeared at the samples prepared at the pH value lower than 12. A series of Sr5-xBax(PO4)3OH samples had beenobtained by adding sodium hydroxide aqueous solution into the Sr-Ba-P solution to pH12.5 and following aging at 60 °C for 24h. The so-prepared samples are metallic cation-deficient hydroxyapatite solid solutions. The samples present low degree of crystallinity, irregular short rod-like morphology and nanometer size. The crystal cell parameters of Ca5-xSrx(PO4)3OH samples are nearly linear to their barium content, and their infrared absorption bands of PO43- groups shift to lower wave numbers with the increase of the barium content.

Mandible defect and the lack of dentition may result in facial deformity and chewing organ defects. It happens after the surgery of oral and maxillofacial tumors. This study aims at this problem. In this study, Finite Element Analysis (FEA) was employed to reconstruct the implanted mandible for customized patient. The 3D FEA model has great importance for biomechanical analysis. Though the analysis of the biomechanical situation with different numbers of dental implants, we can optimize the location and quantity of the implants. In this way, we can improve the quality of the implants, reduce the pain of patients, reduce the operation cost and avoid secondary surgery.

The TiO2 films with hierarchical structure consisting of porous structure and spinodal phase separation structure have been synthesized by sol-gel method. The influence of the different photomonomers, different coating times and different heat treatment temperatures on the structure and photocatalytic activity of TiO2 film has been investigated and the possible mechanism was proposed. The performances of as-prepared TiO2 films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD). The photocatalytic activities of the as-prepared TiO2 films have been carried out by the degradation of methylene blue (MB) dye under the UV irradiation. The results indicated that the as-prepared TiO2 film with hierarchical structure exhibited significant photocatalytic activity, which might be due to its high specific surface area and high-speed electron migration that enhanced the subsequent photocatalytic reactions and led to a positive synergistic effect.

The plasma spraying Al2O3-13%TiO2 (abbreviated as AT-13) ceramic coatings on Q235B steel surface were dealed with laser remelting technique. The microstructure and properties before and after laser remelting were studied. Experiment results shown that the microstructure of laser remelted ceramic coatings was dense, no porosity appeared. The main compositions of laser remelted ceramic coatings were α-Al2O3 and a small amount of TiO2 and TiAl2O5. Microhardness of AT-13 plasma spraying coatings and laser remelting coatings were measured with vickers, and the maximum microhardness value of the former was 1000 HV0.2 , while that of the latter was 1700 HV0.2; The average bonding strength value of AT-13 plasma spraying coating was 24.36 Mpa, while the average bonding strength value of laser remelting coating was more than 67.02 Mpa. The wear resistance of laser remelting coatings was higher than that of AT-13 plasma spraying coatings through the pin-dish particle wear test.

In this paper, based on Ansys the deformation and stress for high pressure long cylindrical natural gas storage tank are analysed. And obtain the stress distribution of the storage tank. The changes of stress are analysed in thickness direction and along the rigid wall. The results and theoretical results are accordance. On this basis, the modal analysis of tank is completed too. Obtained the tank various order natural frequency and vibration mode. The calculation results show that the method is effective and provide the theoretical basis for high pressure tank design

In this paper, based on ANSYS the topology optimization design for high pressure storage tank was studied by the means of the finite element structural analysis and optimization. the finite element model for optimization design was established. The design variables influence factors and rules on the optimization results are summarized. according to the calculation results the optimal design result for tank is determined considering the manufacturing and processing. The calculation results show that the method is effective in optimization design and provide the basis to further design high pressure tank.

This paper introduces ¡p-¡q detection and analyzes the error in detecting the active and reactive current theoretically at the condition of three-phase and four-line at first. Then, it puts forward a new method at the base of ¡p-¡q detection. At last, on the base of MATLAB, the simulation of the new method is demonstrated to be correct and acceptable.

The Lower DOF parallel robot rely on strictly geometrical constraints of axis of pairs in and between limbs to obtain the reduced number of DOF .In practice ,these constraints will never been perfectly fulfilled due to the inevitability of errors, and hence produce series bad effects and problems. Using screw theory and set theory as mathematical tools, the DOF and constraint system of 3-CRR parallel robot, were systematically summarized and in-depth studied. Kinematics design of a limited DOF parallel robot, a 3-CRR pure translational parallel robot, is presented that takes into account the error. The errors presented in the paper consist of two kinds. The errors is defined as the position error of rotation center of the platform caused by errors in the kinematics constants, such as axis error The above research results provided an insight into the error of 3CRR parallel robot.

The subtype of avian leukosis virus (ALV) was mainly determined by the gp85 glycoprotein. A subtype J ALV strain SCDY1 associated with hemangioma was isolated from grandparent breeding chicken and the highly antigenic region of its gp85 gene was amplified and expressed in Rosetta Escherichia coli using the pET-32a(+)vector. The fusion protein, which was expressed at a high level, was similar antigenically to the native gp85 protein as determined by Western blot assay using polyclonal antibodies against ALV-J strain. The fusion protein was also purified. This research lays a foundation for using this recombinant protein for development of indirect enzyme-linked immunosorbent assay (ELISA) for serum antibody detection or for production of monoclonal antibodies against prevalent ALV-J.

A field Marek’s disease virus (MDV), named as BY strain, was firstly isolated from Tibetan chickens in Sichuan province, China, by method of co-cultivation of the lymphocytes with duck embryo fibroblasts (DEF). Analysis of the oncogenic genes showed that there were 2 copies of 132-bp repeated sequence in long terminal repeat of the BY strain, The nucleotide and amino acid sequence identities of Meq gene of BY strain with other prevalent MDV strains in China were 97.6-100.0% and 98.8-100.0%, respectively, and some point mutations assumed to be relevant to the oncogenecity of MDV also existed in the Meq gene of BY strain. The result of animal challenge test on specific-pathogen-free (SPF) chickens showed lymphomas may occur in a variety of organs as early as 18 days post challenge, and the rate of tumor occurrences and mortalities reached to 73.33% and 66.67% in HVT immunized chickens, respectively. In conclusion, an MDV strain charac-terized of acute oncogenicity was isolated from Tibetan chickens in China, though there were no obvious difference between the oncogenic genes of this strain and other virulent MDV strains isolated in China in recent years.

Traction load in electrified railway result in the power supply system contains a lot of negative sequence, harmonic and reactive current. It is necessary to analysis the compensation principle based on active compensation of electrified railway traction power supply system. According to the relation between primary winding and secondary winding of regular traction transformer, we deduced general voltage and general current transform formula, and then deduced completely and negative sequence compensation formulas. It also gives the method of reduce active compensation capacity.

A chelating starch (SMAEN) containing amidocyanogen and acyl functions was prepared through a two-step reaction. The structure of SMAEN was determined by FTIR spectrum. The amination extent was traced by estimating the nitrogen content of SMAEN. The SMAEN was tested as an adsorbent in Cu2+ metal aqueous solution. The parameters influencing the efficiency of preconcentration Cu2+ including sample acidity, adsorption conditions were investigated. The Cu2+ ion was accomplished good adsorption amount at pH＞4. The maximum adsorption capacity was 2.69mmol per gram of dried SMAEN.

The performance advantages of the newly full-hydraulic internal circulation two-platen injection molding machine were investigated deeply and comprehensively. The application prospects were also forecasted. Thanks to the use of internal circulation cylinders in the injection molding machine, the hydraulic system is greatly simplified. Mold-moving and mold-locking are actuated by different cylinders respectively which not only balance the force and velocity but obtain excellent mold-locking properties and high molding stability. The injection molding machine was equipped with servomotor which drives quantified pump in order to save energy and lower noise. The newly full-hydraulic internal circulation two-platen injection molding machine will be the next generation injection molding machine.

This paper introduces the basic theory and significance to study injection molding defects. By virtue of the visualization experimental equipments, generation processes of several typical defects are directly observed and recorded. The generation mechanism of these defects is analyzed. Finally future study plan is advanced.