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Graphene oxide (GO) was prepared by modified Hummer’s method, and reduced by solvothermal method using ethanol as the solvent and modified diethylene triamine (amine curing agent 593) as reducing agent and modifier. The effect of reduction time and temperature on the structure and conductive property of reduced graphene oxide (593-rGO) was investigated by SEM, FT-IR and XRD. The results show that the graphene modified by 593 is obviously improved in dispersibility and sedimentation stability in dichloromethane, as well as in conductivity. The optimal reduction processing is that the mass ratio of GO to 593 is 2:1, the reduction time and temperature is 6 h and 160°C, respectively.

Meshless collocation method based on generalized multiquadrics radial basis function is used to study the free vibration of simply supported laminated composite plates. The generalized multiquadric radial basis function g=[r2+c2]q has the exponent q and shape parameter c that play an important role in the accuracy of the approximation. Genetic algorithm is utilized to optimize the shape parameter and exponent of generalized multiquadrics radial basis function. The natural frequencies of simply supported laminated composite plates are calculated using the generalized multiquadrics with optimal shape parameter, exponent and compared with the analytical solutions.

Free vibration of simply laminated composite plates is studied by the global collocation method based on inverse multiquadrics radial basis function. The choice of shape parameter of radial basis function has the important effect on the accuracy of meshless radial basis function collocation method. Genetic algorithm is used to optimize the shape parameter of inverse multiquadrics radial basis function. The natural frequencies of simply supported laminated composite plates are calculated using the inverse multiquadrics radial basis function with optimal shape parameter and compared with the analytical solutions.

A numerical model has been established and solved to describe the dehydration reaction from alcohol to ethylene. The influences of the gas velocity and the temperature of the feeding gas to the process of the reaction were discussed. The results showed that, the influence of the radial diffusion on the reaction characteristics could be ignored while the influence of radial heat conduction to the temperature distribution was significant. The temperature distribution decreased alone the axial direction at first and then increased, that is a lowest point of the temperature could be found. When the velocity of the gas slowed down or the temperature of the feeding gas increased, the conversion of the reactant and the selectivity of the target product could be improved, the distance of the lowest temperature point to the entrance got closer and the outlet temperature became higher.

In the present paper, the higher order shear deformation theories of Touratier and Karama and meshless global collocation method based on the inverse multiquadric radial basis function are used to analyze the bending response of the exponentially graded plates. The material properties of the plates vary exponentially in the thickness direction. The present results are compared with three-dimensional elasticity solutions.

The research examines the phosphorus removal efficiency of modified fly ash on landscape water and its influencing factors, and also study the actual eutrophication landscape water . Results show that when the solution pH is controlled in the range of 5 ~ 9, agitation speed is 150r. min -1and the additive amount modified fly ash is 1.2 g·L-1, the oscillation adsorption time and adsorption temperature are respectively 60 min and at room temperature, for the raw water whose initial concentration of total phosphorus is 10.0 mg·L-1 , the adsorption rate is 98.4%,which has a good adsorption effect. The test about Real urban landscape water shows total phosphorus is 0.35 mg·L-1 , when the additive quantity of modified fly ash is 200 mg·L-1, the concentration of the water reduce to the level of 0.01 mg·L-1 ,which is up to the first class of landscape water quality standard (GB18921-2002)

In this paper the governing equations of cross-ply symmetric laminated composite plates are derived based on the trigonometric shear deformation theory. Generalized Navier type solutions are obtained to predict the free vibration behavior of cross-ply symmetric laminated composite plates. The analytical solutions of natural frequencies are obtained for thick and moderately thick plates as well as for thin plates, and compared with some available results in other papers. Through numerical examples, the high accuracy of present method for free vibration analysis of cross-ply symmetric laminated composite plates is demonstrated.

Through pseudo static test on three pieces of fiber reinforced plastics (FRP) transfer beam supported frame with three different reinforcement form, reinforcement ratio and the number of root reinforcement ,which are subjected to the vertical load and horizontal low cycle reciprocating load, the specimen fracture development law, yield mechanism, failure pattern, and bearing capacity, ductility, hysteresis characteristics and seismic performance are analyzed. The test results show that: yield mechanism and failure pattern of transfer beam supported frame equipped with fiber reinforced plastics reinforced bars are reasonable. The bearing capacity and deformation performance of transfer beam supported frame with top and bottom longitudinal bar replaced by FRP bars and symmetrical reinforced box are better than that of single upper replacement for FRP and lower replacement for FRP. The ductility performance of transfer beam supported frame equipped with fiber reinforced plastics bars is good, hysteresis curve is full, and have good seismic performance.

Experimental studies of the long-term performance such have been done in this paper for sea water and sea-sand concrete and sea water and coral sand concrete, such as the elastic modulus, frost resistance and corrosion of reinforcement behavior. The test results show that the compressive elastic modulus of the sea water and sea sand concrete and the sea water and coral sand concrete are slightly lower than that of ordinary concrete, while the adding of fly ash or ground slag in them lead the late compressive elastic modulus slight increase. Compared with the ordinary concrete after freeze-thaw cycle, the mass loss rate and the compressive strength loss rate of the sea water and sea sand concrete and coral sand concrete are slightly larger, but slightly reduced by mixing with ground slag in the concrete, while a little high by mixing with fly ash. Due to the presence of Cl- in the saltwater and sea sand concrete and coral sand concrete, [Cl-] / [OH-] values will be larger, which leads to corrosion of internal reinforced, so it is necessary to adopt appropriate ways to modification for the concrete and reinforced.

The paper analyzes the changes of factors that influence competitiveness of cloud outsourcing facilitators under the promotion of cloud computing technology from perspective of vendor, and gives a fuzzy comprehensive model of competitiveness of vendor.

In this paper, the mechanical property experiments of concrete based on the seawater and sea sand have been carried in different raw materials preparation and different conservation environments. The results show that the early strength and late strength of concrete based on seawater and sea sand are better than concrete based on freshwater and sand. There is no significant strength decreased for concrete based on seawater and sea sand under accelerated alternating wet and dry conditions. For concrete based on seawater and sea sand mixed with admixture, the downward trend of late strength is significantly delayed, the late strength of concrete based on the seawater and sea sand mixed with slag gets the most obvious growth trend, while the late strength of seawater and sea sand concrete mixed with fly ash gets the largest increment.

Coatings such as Cr, Ni, Ti, and SiO2/SnO2 on solar-control and low-emissivity (low-E) glasses are commonly used in the energy efficient glass windows. However, coloring in the re-manufactured glass panels using recycled window glasses resulting from the coatings reduces the glass transparency significantly. Traditional ways to remove coatings by manual wheels and pneumatic removal machines are labor intense and slow processes. In this study a new way to remove the coatings on recycled coated glasses was investigated. The Ultra Violet/Visible/Infrared (UV/VIS/IR) spectra and Secondary Electron Microscope (SEM) pictures were taken before and after 30s. atmospheric pressure oxygen plasma treatments. It was confirmed that the atmospheric oxygen plasma treatment is a fast, efficient, and low pollution way to remove the coatings before the remanufacture of recycled glasses. Other than the physical sputtering off the coatings from the plasma, there are many excited oxygen species in the plasma which effectively react to the coating and the products are then removed.

This study demonstrates the thermal actions of tert-butyl peroxybenzoate (TBPB) which is widely used in the plastic and rubber industries. The thermodynamic and kinetic analysis were performed on the basis of dynamic and adiabatic calorimetric applications which had been accepted as good assistants for investigating materials’ thermal decomposition. In essence, TBPB is reactive and exothermically unstable. Differential scanning calorimetry (DSC) and accelerating rate calorimeter (ARC) were employed to supply basic data and safety index. Experiments were taken under different scanning rates as well as various sample mass. The temperature and pressure curves of TBPB during decomposition were recorded. Based on the significant parameters calculated, self-accelerating decomposition temperature (SADT) of TBPB worked out was 50°C.

Removal of low concentration of phenol from aqueous solutions through the adsorption process by using crosslinked β-Cyclodextrin polymer (β-CD polymer) was investigated. The effects of contact time, sodium chloride content, contact temperature and initial concentration of phenol in the aqueous on adsorption capacity were evaluated through a series of batch experiments. The results show that β-CD polymer on the adsorption of phenol balanced after 6h. The adsorption process was apparently influenced by sodium chloride content, contact temperature and initial phenol concentration in aqueous solution. The adsorption behavior for phenol of β-CD polymer is fitted into the Freundlich isotherm.

In order to improve the efficiency and quality of design of complex parts, cycloid gear, in the pin-cycloidal transmission, this paper used SolidWorks to built accurately cycloid gear 3d model, and the VBA to program procedure for the secondary development, realized the parametric design of cycloid gear. Designer just enter the design parameters of cycloid gear , then gain the accurately generated cycloid gear 3d model rapidly , greatly improving the speed of cycloid gear design.

Photoelectrocatalytic oxidation of methyl orange on TiO2 films were investigated in KNO3 solution. In the potential range up to 1.2 V, electro-degradation rates were fairly low that was less than 1%. Degradation rates on the two films were larger at higher potentials. The film prepared without PEG showed better activities than the film prepared with PEG during the whole range of potential. Methyl orange degradation rate increased with increasing KNO3 concentration from 0 to 0.010 mol/l. After 120 min of irradiation, methyl orange degradation rate on the film with PEG was 89.5%, while degradation rate on the film without PEG was 92.0% after the same period.

According to the assumption of local thermal non-equilibrium and the heat transfer controlled regime, a mathematical model describing the coupling between the heat and mass transfer processes in a porous packed bed with endothermic chemical reactions was established and solved by the alternate dimension implicit method. The calculated results showed that, the profiles of the temperature distributions of the two phases and the solid conversion ratio all decay near the radial boundary wall corresponding to the momentum boundary layer. However, the concentration of the product gas increases near the wall owing to the slower speed layer. The temperatures difference between the gas flow and solid pellets can not be ignored during the study of ore decomposition in the porous packed bed. The reaction features of the packed bed with endothermic reactions under different conditions can be analyzed by the established model.

The dynamic time-history response analysis method was employed to analyze the dynamic response of composition foundation with CFG piles. The deformation and stress distribution of composite foundation of CFG piles with different length and amount of piles under seismic wave was investigated. The results reveal that the bearing and asti-deformation capacity could be improved effectively for composite foundation under earthquake loads by increasing the length and number of pile. The vertical stress of foundation soil decreases gradually with the increase of the length and number of pile. The practice shows that CFG piles provide a positive contribution to the aseismic effect of foundation soils mass. The present research can provide some references to similar projects.

Gregory’s decomposed theorem of isotropic plate is extended to investigate torsional circular shaft for two-dimensional dodecagonal quasicrystal (2D dodecagonal QCs)with homogeneous boundary conditions, and the theory of equivalence that Cheng’s refined theory and Gregory’s decomposed theorem is extended to the cylindrical coordinate. The decomposed theorem of torsional circular shaft of 2D dodecagonal QCs with homogeneous boundary conditions is proposed on the basis of the classical elasticity theory and stress-displacement relations of 2D dodecagonal QCs without ad hoc assumptions. At first expressions are obtained for all the displacements and stress components in term of some 1D functions. Using Lur’e method, the exact equations were given. And the exact equations for the torsional circular shaft on 2D dodecagonal QCs without surface loadings consist of four governing differential equations: two harmonic equations and two transcendental equations.

In order to validate the pin-hole-output mechanism of FA cycloid drive force analysis theory, and based on the study on the basis of the contact problem, this article used the international advanced finite element analysis software ANSYS, established the output dowel pin and cycloid gear pin hole's contacting finite element model, and analyzed the static three-dimensional contact analysis. The calculation results coincided with the proposed pin-hole-output mechanism with gap dynamic stress analysis method, proved the correctness of the stress analysis theory.

The fire-resistant properties of FRW fire-retardant particleboard and untreated particleboard had been measured under a heat flux of 75 kW/m2 by cone calorimeter (CONE). Through the compare between FRW fire-retardant particleboard and untreated particleboard, the influence on the particleboard by FRW fire retardant had been indicated. The results showed that the indexes of heat release rate (HRR), total heat release (THR) and efficient heat combustion (EHC) etc of FRW fire-retardant particleboard were obviously reduced contrast to the ordinary particleboard, but the char-forming rate had a high increase.

In order to improve the human engineering characteristics of the table tennis wheelchair and promote sport wheelchair, the design of a Table Tennis wheelchair was improved based on the human engineering. With the PRO/E software the table tennis wheelchair three-dimensional model is built and with the CATIA software the three-dimensional human body model is established. At last, in order to validate the human engineering performance of the improved table tennis wheelchair, we carried on the wheelchair man-machine engineering simulation, the operating space analysis of containing, balance analysis and body posture comfort level analysis and appraisal. The results indicated that the improved table tennis wheelchair can satisfy the human engineering request of the security, the efficiency and the comfort.

PET/PTT conjugate yarn has a three-dimension spiral and permanent crimp, which endow the yarn and loomage with excellent performances of crimp extension and crimp recovery. The residual deformation and internal stress of the self-crimp yarn can be eliminated after the moist heat treatment, in order to develop the favorable crimp extension and crimp recovery of the self-crimp yarn, and to give the loomage soft handle and good dimension stability. Crimp shrinkage, crimp module, etc, of the different types of PET/PTT yarn, were tested, and the axial morphology of the yarn was observed, to investigate the effect of linear density, moist heat temperature on PET/PTT yarn.

Taken the pore structure effects into account, a mathematical model to describe the interaction of mass transfers, the chemical reaction and the pore structure in the gas sensitive porous medium is presented and solved. The properties of the mass transfers and the reaction characteristics of the gas-sensitive porous system are analyzed. The effects of pore size distribution and porosity on the concentration field of detected gas and the effective utilization degree of the porous matrix are provided. The results indicate that the Thiele number, which can reflect the relative magnitude of chemical reaction rate and gas diffusion velocity in nature, is the main basis for judging the effects of various parameters. It usefully reproduces the observed effects of pore structure and reaction temperature on diffusion and chemical reaction response, showing that the gas sensitivity and the effective utilization coefficient of the gas sensitive porous medium can be controlled by adjusting key parameters.

Cheng’s refined theory is extended to investigate torsional circular shaft of two-dimensional dodecagonal quasicrystal (2D dodecagonal QCs), and Lur’e method about harmonic function is extended to harmonic function in the respective cylindrical coordinate. The exact deformation of torsional circular shaft of 2D dodecagonal QCs under reverse direction surface loading is proposed on the basis of the classical elasticity theory and stress-displacement relations of 2D dodecagonal QCs, and the exact deformation theory provides the solutions about torsional deformation of a circular shaft without ad hoc assumptions. Exact solutions are obtained for circular shaft from boundary conditions. Using Taylor series of the Bessel functions and then dropping all the terms associated with the higher-order terms, we obtain the approximate expressions for circular shaft of 2D dodecagonal QCs under reverse direction surface. To illustrate the application of the theory developed, one example is examined.

Cheng’s refined theory is extended to investigate torsional circular shaft of cubic quasicrystal, and Lur’e method about harmonic function is extended to harmonic function in the respective cylindrical coordinate. The refined theory of torsional circular shaft of cubic quasicrystal under reverse direction surface loading is proposed on the basis of the classical elasticity theory and stress-displacement relations of cubic quasicrystal, and the refined theory provides the solutions about torsional deformation of a circular shaft without ad hoc assumptions. Exact solutions are obtained for circular shaft from boundary conditions. Using Taylor series of the Bessel functions and then dropping all the terms associated with the higher-order terms, we obtain the approximate expressions for circular shaft of cubic quasicrystal under reverse direction surface. To illustrate the application of the theory developed, one example is examined.

Gregory’s decomposed theorem of isotropic plate is extended to investigate torsional circular shaft of cubic quasicrystal with homogeneous boundary conditions, and the theory of equivalence that Cheng’s refined theory and Gregory’s decomposed theorem is extended to the cylindrical coordinate. The general solution of torsional circular shaft on cubic quasicrystal with homogeneous boundary conditions is proposed on the basis of the classical elasticity theory and stress-displacement relations of cubic quasicrystal without ad hoc assumptions. At first expressions are obtained for all the displacements and stress components in term of some 1D functions. Using Lur’e method, the exact equations were given. And the exact equations for the torsional circular shaft on cubic quasicrystal without surface loadings consist of four governing differential equations: two harmonic equations and two transcendental equations. Using basic mathematic method and the general solutions, an example is examined.

Through generalizing the method of a decay analysis technique determining the interior solution developed by Gregory and Wan, a set of necessary conditions on the end-data of axisymmetric circular cylinder in cubic quasicrystal for the existence of a rapidly decaying solution is established. By accurate solutions for auxiliary regular state, using the reciprocal theorem, these necessary conditions for the end-data to induce only a decaying elastostatic state (boundary layer solution) will be translated into appropriate boundary conditions for the circular cylinder with axisymmetric deformations in cubic quasicrystal. The results of the present paper enable us to establish a set of correct boundary conditions, and mix boundary conditions of which are obtained for the first time.