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The human wrist has three rotational DOFs. Elbow muscle group work together to drive the wrist joint. According to the above characteristics of human wrist, parallel mechanism with three rotational DOFs of the imitation of human wrist is built. Traditional method for calculating DOF based on arithmetic is not that accurate. The method for analysis of DOF based on theory of constraint screw is explained. According to theory of constraint screw, the parallel mechanism built was analyzed. All the kinematic pairs in the mechanism will be expressed with screws so that the common constraints and the over constraints will be obtained. Through analysis above, the DOFs of the mechanism can be calculated and which a few degrees of freedom of the mechanism will be known. The new method avoids the disadvantages of the traditional method.

In this paper, the chitosan was prepared for treatment of electroplating wastewater. The influence of temperature, PH value, the amount of chitosan and mixing time on the effects of the wastewater treatment was investigated. The result showed that at PH=3, with the addition of 0.6g chitosan and 2h of mixing, the optimum wastewater treatment effect can be obtained. The removal rate of COD is above 80% and the adsorption rate of copper ion is above 99%. The decolourization ratio and the turbidity indicated that the treatment is effective.

Q43Y-85D type crocodile hydraulic clipping machine was taken as research object to optimization design. A finite element model for clipping machine was built using shell unit as fundamental unit. ANSYS12.0 finite element method was used to analyze the deformation and stress distribution of the shear platform model of hydraulic clipping machine. The result showed that the maximum equivalent stress at the dangerous area was 368.162 MPa and the maximum elastic strain was 0.1814×10-2 mm. After the structural optimization design, it was found that the maximum equivalent stress decreased to 186.238 MPa which did not exceed the material’s yield limitation 215 MPa and the maximum elastic strain decreased to 0.919×10-3 mm which satisfied the requirement of stiffness.

Transparent conducting aluminum-doped zinc oxide (AZO) films with different film thickness had been prepared on soda-lime glass substrates by radio frequency magnetron sputtering using a high density ceramic target. The structural, morphology, electrical, and optical properties of the AZO thin films were investigated by X-ray diffraction, scanning electron microscope, Hall-effect measurement and optical transmission spectroscopy, which were strongly influenced by film thickness. With the film thickness increasing from 140 nm to 710 nm, the resistivity decreases from 9.78 × 103 to 3.23 × 103 Ω.cm and an average optical transmission decreases from 88% to 80% in the visible range and the optical bandgap decreases from 3.47 to 3.24 eV.

The curriculum construction is a very important work leading to the excellent course. Welded Structure (including 40 class hours) is one of main and compulsory course for the major of Material Molding and Control Engineering in our university. It is very important and necessary to construct the course in time. Based on the project of High Quality Curriculum Construction for Welded Structure undertaken by the authors, this paper makes a discussion on the original ideas, goals and contents, strategies and measures of the project. Meanwhile, the course construction and reform of Welded Structure are introduced from following aspects, such as curriculum setting, teaching contents and methods, teaching staffs, teaching quality management and supervision, online teaching resource construction. The purpose of the paper is to provide beneficial references and experiences to facilitate the further curriculum construction and reform in higher school.

Ba0.6Sr0.4TiO3 (BST) thin films were fabricated by solgel technique on Pt/Ti/SiO2/Si substrate without and with PbO seeding layer from precursor solutions with different concentrations. The crystal structure, surface morphology, dielectric properties and leakage current density of BST thin films are investigated as functions of the concentration of PbO precursor solution. Its found that the growth orientation of BST thin films with PbO seeding layer can be modulated through adjusting the concentration of PbO precursor solution. BST thin film with PbO seeding layer from 0.05 M precursor solution shows the highest dielectric constant and tunability, which may be attributed to the high crystallization and amplitude of the polarization in high (100) preferred orientated films. The leakage current density of BST films increases with the increasing concentration of PbO precursor solution and agrees well with the space-charge-limited current mechanism at room temperature.

Using the FLUENT software, this paper taking the wind load shape coefficient in the current code for the design of building structures as the comparison standard, have numerical wind tunnel simulation of the wind the surface wind pressure on arch roof. It focused on the effect of the different turbulence models on the numerical simulation, such as Spalart-Allmaras, Standard k ε, RNGk ε, Realizablek ε, Standard k ω, SST k ωand RSM. It provided reasonable reference for selection of turbulence model.

Using the FLUENT software, this paper taking the wind load shape coefficient in the current code for the design of building structures as the comparison standard, have numerical wind tunnel simulation of the wind the surface wind pressure on low layer double slope roof. It focused on the effect of four convective term difference schemes on the numerical simulation, such as First-Order Upwind, Second-Order Upwind, Power Law and Quadratic Upwind Interpolation for ConvectiveKinematics. It provided reasonable reference for selection of convective term difference format.

With the rapid development of computer science, image processing, and pattern recognition, people are paying more and more attention on research and application of machine vision, which has resulted in excellent results in many fields. Depending on the features of untouched, fast-speed, real-time, proper precision, anti-interference, the inspection technology based on machine vision has been researched deeply and comprehensive applied aboard. Recently, the size measurement technology based on machine vision has been applied in the size measurement of the machine processing parts. A case study of typical regular mechanical parts, algorithm of position and size measurement of line, circle center and radius are researched, and good results are got, which established an academic foundation for further measurement of complex parts.

A steady thermal conduction model was presented to study the temperature field and thermal stress distribution in film irradiated by continuous wave laser. The thermal effects may arise from either the absorbing inclusions or the intrinsic absorption of film. Based on the plane thermal conduction assumption, the characteristics of damage resulted from local melting or evaporation and thermal stress were discussed. The damage region resulted from local melting or evaporation smaller than that from thermal stress. The circumferential stress σθis the main cause accounting for the stress damage. The normal stress perpendicular to the interface between film and substrate is the direct cause of drum type damage. The characteristics of damage in unsteady thermal conduction caused by pulse laser can be analyzed qualitatively by means of this model.

Ultrasonic intensity has a great influence on the concentration of cavitation bubbles. Considering the characteristic of cavitation, in this paper, we propose a method of measuring the amount of cavitation bubbles to identify the change of cavitation intensity indirectly. First, acquires images of reaction liquid under the action of the certain power ultrasonic through machine vision technology; then, obtains micro bubbles quantity generated by ultrasonic cavitation; finally, establish the mathematical model between cavitation intensity and amount of cavitation bubbles to indirectly detect the change of ultrasonic cavitation intensity.

The hydrolysis of cinnamaldehyde in aqueous solution catalyzed by amino acids has been investigated. Eight amino acids e.g. glycine, proline etc. have been employed as the small molecular organocatalysts. The effect of reaction time, temperature, buffer concentration on the reaction has been studied. Spectroscopic analysis indicated the reaction product is 3-hydroxy-3-phenylpropanal.

The epoxy acrylate emulsion was made by hybrid emulsion polymerization. This method has simple technology, none solvent and friend to the environment. The epoxy acrylate hybrid emulsion was prepared by using core-shell emulsion polymerization technology. The factors, such as epoxy resin, emulsifier ,initiator and functional monomer, were investigated by the orthogonal experiment. The relation of interactional factors was confirmed, and one kind of steady emulsion was made. The best formulation condition of modified emulsion could be obtained when N-MA was 1%, MAA was 2%, emulsifier was 3%, epoxy resin was 6%, initiator was 0.6%. The structure of modified styrene acrylic hybrid emulsion was characterized by FT-IR, the peaks at 915cm-1 and 1251cm-1 correspond respectively to the motion of epoxy group and phenylate, so the graft polymer was confirmed.

For the problem of analysis of earthquake response of cable-stayed tower bridge, the foundation is given as the rigid consolidation, do not consider the interaction of soil and structure, the finite element software ABAQUS is used for seismic response analysis. Taking the TCU052 and EI Centro wave which have different characteristics as the input of bridge tower, first to carry out the modal analysis of bridge tower structure, get various order of modal frequency of the bridge tower, then analyses the displacement response of the top of bridge tower in the bridge direction, the results showed that, under the pulse type seismic action the displacement response of bridge tower of large span cable-stayed bridge are increased.

In order to research the influenced factors of sensitivity of ultrasonic nondestructive testing, the compared experiments using water immersion and contact method were carried out and the experimental results of sensitivities were obtained. The results showed that the limited sensitivities of probes with 1MHz and 2.25 MHz is very low. And the defects ofφ1mm, which distance not exceeding 1mm, can be detected by probes of 5 MHz and 10 MHz. The defects ofφ0.5mm can be detected by probes of 15 MHz and 20 MHz. The definition of defects apperance will be further improved for the probes with their frequency more than 15 MHz when the scanning step enough small. The distance of probes and defects has little effect on the detecting sensitivity.

Based on the surface morphology, a model is presented to investigate the heat transfer in anodic aluminum oxide (AAO) porous thin films. The extra thermal resistance from the micropores will inevitably cause a change in thermal properties, which can be analyzed by the Fourier law. The effect of the characteristic size on the thermal conductivity is discussed in details by means of the theory of phenomenological model of phonon scattering. Considering the effects of porosity and the distribution of micropores reflected by parameter D, the function of the effective thermal conductivity of AAO porous thin films expressed by two independent variables, εp and D. The temperature field is simulated with the effective thermal conductivity and the result demonstrates a bigger temperature rise in AAO porous thin films.

Transparent conducting aluminum-doped zinc oxide (AZO) films have been prepared on soda-lime glass substrates by radio frequency magnetron sputtering using a high density ceramic target at different substrate temperatures. The structural, morphology, electrical, and optical properties of the AZO thin films were investigated by X-ray diffraction, scanning electron microscope, Hall measurement, and optical transmission spectroscopy, and which were strongly influenced by substrate temperatures. Films with better texture, higher transmission, lower resistivity and larger carrier concentration were obtained for the samples fabricated at higher substrate temperature. The AZO film with the lowest resistivity of 4.63×10−4 Ω.cm and an average optical transmission of 92% in the visible range was deposited on the substrate heated at 450 °C. The optical bandgap depends on the deposition condition, and was in the range of 3.35~3.59 eV.