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The oxidation behavior of FGH720Li(P/M Udimet720Li) superalloy was investigated under static atmosphere in temperature ranging from 600°C to 730°C. The oxidation kinetics, composition and morphology of the oxidation layers were characterized by means of isothermal oxidation tests, X-ray diffraction(XRD), scanning electron microscopy（SEM）and energy dispersive X-ray spectroscopy(EDS). The results showed that the oxidation kinetics curves of FGH720Li superalloy followed the parabolic law. The results of cross-sectional morphology and elemental distribution indicated that the oxidation layer could be divided into three parts：porous Cr2O3 outer layer, dense Cr2O3 medium layer and oxidation affected zone with nail-like Al2O3 inner layer. The oxidation process was primarily controlled by the diffusion of chromium and oxygen through the oxide scale.

S-doped TiO2 nanoparticles were fabricated by hydrothermal process and post-calcination, and their morphology, crystalline phase and chemical composition were characterized with transmission electron microscopy, powder X-ray diffraction and selected area electron diffraction. The results showed that S was successfully doped into the TiO2. We investigated the photocatalytic reactions in a simulated environment in tandem with thermal desorption-gas chromatography-mass spectrometry determinations. The catalytic activity of S-doped TiO2 was evaluated by monitoring the photodegradation of BTEX from wood-based panels, and 95% degradation rate in 75 min demonstrated efficient visible-light catalytic performance.

The Polyamide 6 (PA6)/ maleic anhydride grafted ethylene-propylene-diene monomer (EPDM-g-MAH)/organic montmorillonite (OMMT) nanocomposites were successfully prepared by melt extrusion method at different contents of OMMT fillers. The content of OMMT were studied to discuss the mechanical properties, thermal resistance properties and melt-crystal behavior of the nanocomposites. The results were summarized as follows: The PA6/EPDM-g-MAH/OMMT nanocomposites were prepared using melt extrusion method. The influence of the OMMT filler contents on the properties of PA6/EPDM-g-MAH/OMMT nanocomposites were studied. The mechanical properties and thermal resistance properties were improved with the addition of OMMT. The results showed that when the content of OMMT was 3.5wt%, comparing to the pure PA6, the bending strength was improved 31.7%, the notch impact strength was improved by 40.5%, and the heat deflection temperature was improved by 31.1°C. This kind of nanocomposites had good application prospects.

By mechanical blending method or melt extrusion method, several kinds of poymers and OMMT were selected with different mixing progress and conditions, and several polymer/OMMT nanocomposites with different substructure morphology were prepared. The properties of polymer/OMMT nanocomposites were investigated. Firstly, several types of OMMT were prepared with different layer spacing, the results of XRD and TEM showed that the OMMT with larger layer spacing would form exfoliation nanocomposites, and then the schemes explained the mechanism. The polyethylene (such as LDPE, HDPE, LLDPE) composited with the same OMMT indicated the influence of different molecular chain structure. Different morphology of PP/OMMT and EPDM/OMMT nano-composites were discussed to find the relationship of shear force effecting structure.

Magnesium-aluminum hydrotalcite and carbon nanotube composites (CNTs/MgAl-LDHs) were prepared by one-step hydrothermal method using magnesium nitrate, aluminum nitrate and carbon nanotubes as raw materials and urea as precipitant. The samples were characterized by SEM, XRD, BET and other methods. The adsorption properties of CNTs/MgAl-LDHs on chloride ions and the factors affecting the adsorption of chloride ions were studied. The results show that the prepared CNTs/MgAl-LDHs exhibit a three-dimensional honeycomb structure with a specific surface area of 103.019 m2/g, which is larger than the specific surface area of MgAl-LDHs of 84.344 m2/g. The results showed that the optimal adsorption conditions were: adsorption temperature was 45°C, the pH value was 8, the adsorption time was 100 min, the Cl- concentration was 0.01 M (584 mg/L), and the adsorbent concentration was 1.0 g/L. CNTs/MgAl-LDHs has the best adsorption performance for chloride ions. The maximum adsorption capacity is 75.58 mg/g. The adsorption isotherms and adsorption kinetics are consistent with the Langmuir isotherm model and the quasi-secondary kinetic model.

Using magnesium nitrate, nickel nitrate and aluminum nitrate as raw materials and urea as precipitant, magnesium nickel aluminum ternary hydrotalcites with large specific surface area were prepared by hydrothermal method. The prepared samples were characterized by SEM、XRD、BET and EDS etc., respectively. The adsorption properties of MgNiAl-LDHs, MgAl-LDHs and their calcined products (MgNiAl-LDOs, MgAl-LDOs) for chloride ions in solution were investigated. The results show that MgNiAl-LDHs are cubic with rod-like structure, with a specific surface area of 197.62 m2/g, which is much larger than that of MgAl-LDHs (102.82 m2/g). Under the same adsorption conditions, the saturated adsorption capacities of MgNiAl-LDHs and MgAl-LDHs for chloride ions are 130.06mg/g and 110.02 mg/g respectively. MgNiAl-LDOs showed better adsorption ability for chloride ions. By simulating the adsorption data, the results show that the adsorption kinetics and the adsorption isotherm are in accordance with the quasi-second-order kinetic model and the Langmuir isotherm model, respectively.

A series of mesoporous silica materials (SBA-15, MCM-41, KIT-6) with different pore structures and properties were synthesized and characterized by means of small angle X-ray scattering, transmission electron microscopy, infrared spectroscopy and nitrogen adsorption-desorption. The adsorption properties of three mesoporous silica materials for chlorine ions in aqueous solution were investigated. The results show that SBA-15, MCM-41 with two-dimensional hexagonal structure has a better adsorption effect on chloride ion than KIT-6 With cubic core structure, and MCM-41 with larger specific surface area and smaller pore size has better adsorption effect on chloride ion than on SBA-15. The specific surface area of MCM-41 is 1036 m2/g, and the The adsorption kinetics accords with the pseudo-second-order kinetic model, and the adsorption isotherm is more consistent with the Langmuir isotherm model. The optimum operating conditions for MCM-41 to adsorb chloride ions are as follows: temperature 55 °C, pH 6, adsorption time 2 h, Cl-concentration 0.01 mol/L (584 mg/L) and adsorbent concentration 1.0 g/L. Under these conditions, the adsorption capacity of MCM-41 to chloride ions is greatly enhanced, and the maximum adsorption capacity is 188.18 mg/g.

The effect of alloying elements on the volume fraction of γ′ phase at aging temperature was investigated. The results indicated the volume fraction of γ′ was mainly sensitive to Al, Ti, Nb, Ta, and Cr. Based on analyzing the chemical component and the volume fraction of γ′ phase of 20 kinds of nickel-base superalloys , a linear regression formula between the volume fraction of γ′ phase and alloying element content was established using Matlab software, and the formula was given as: Vγ′=21.06+5.76Al+0.41Co-0.95Cr+0.84Hf+2.15Nb+0.82Ta+3.06Ti, where the correlation coefficient r = 95.5%. This linear equation was more accurate compared with the three public empirical formulas.

The microstructure evolution and properties of Al-matrix in homogenized 7A56 alloy were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), electrical conductivity and hardness test. The second phases in as-cast 7A56 alloy consisted of AlZnMgCu, Al2Cu and Al7Cu2Fe. With the homogenization temperature increasing, more non-equilibrium phase AlZnMgCu was dissolved into Al-matrix. The diffusion of alloying elements from AlZnMgCu phase into Al-matrix leads to a decrease of electrical conductivity and an increase of hardness. The lattice constant of α-Al has an increases of 0.0019 Å, 0.0032 Å and 0.0053 Å after 380°C/24h,430°C/24h,and 470°C/24 h treatment,respectively.

Thermal stabilities of microstructure and mechanical properties during long-term aging of 550°C/1500h, 650°C/1500h and 700°C/500h have been investigated on superalloy FGH95, in order to characterize the long-term properties of this alloy on service temperature. The results showed that the secondary and tertiary gamma-prime maintained good thermal stability at 550°C and 650°C with aging time up to 1500h. However, during 700°C aging for 500h, the secondary and tertiary γ′ both grew obviously, besides, the shape of secondary γ′ has turned from circular to square. The hardness, high-temperature tensile and creep residual strain had good stability at 550°C and 650°C with aging time up to 1500h. However, the creep residual strain apparently increased when the alloy aged at 700°C for 500h, which means that the FGH95 is suitable to be used for long time below 650°C, and short time at 700°C.

Thermo-gravimetric technology was used to rapidly evaluate and measure safe use life of food contact polymer materials. The thermo-gravimetric curve showed that silicone rubber pad decomposition temperature was about 350°C in air and the maximum decomposition rate was 450°C. 370°C, 380°C, 390°C, 400°C, 410°C at the right temperature zone was chosen to do thermo-gravimetric constant temperature experiments; the time of silicon rubber pad’s weightlessness of 5%, 10% 15% was calculated by the above curve, respectively. Finally Arrhenius equation was used to establish the relationship between temperature and time; and then the result of infer silicone rubber pad using life was 1.37 thousand times when it was used as a baking tray.

In this work, a new type of B13P2 reinforced Cu matrix composite (B13P2/Cu) with excellent wear resistance properties has been fabricated. The experimental results reveal that when the total content of P and B was 3wt.% and the mass ratio of P to B was 2:3, the brittle reticular divorced eutectic Cu3P disappeared and B13P2 phase uniformly distributed in Cu matrix. The microstructure can be controlled and designed according to the ratio of P and B. The microhardness of B13P2 reached up to 1837 HV, which was as high as that of SiC, while the mircohardness of Cu matrix was about 5 times more than pure that of Cu. The wear resistance data indicate that the largest weight loss of pure Cu was approximately four times more than that of the B13P2 reinforced composites at the 40 min. The CTE of the new composites also decreased as compared with pure Cu.

A type of Magneto-Rheological Materials (MRMs) was prepared. The off-state viscosity and the shear stress of the MRMs were characterized and studied by an advanced rotational rheometer system. A kind of Self-Decoupling Magneto-rheological (SDMR) damper was established based on these MRMs. An intellectual isolation system for grid structures was obtained by integrating SDMR damper and isolation device. The seismic whiplash effect of the top bent frame column and space grid roof of the hydropower plant could be reduced. Furthermore, the half stable increment method was proposed as the semi-active strategy. The results indicated that the SDMR dampers used at the grid roof supports setting plate rubber bearings can significantly improve the vibration performance and energy dissipation structure roof isolation system in different seismic intensity. In addition, these SDMR dampers can effectively reduce the lateral slippage of the plate rubber, so as to avoid failure or damage of the isolation system because of the transfinite horizontal displacements. Compared with the conventional damper only in case of multiple earthquakes, the damping force and adjustable multiple of this SDMR damper have better adaptability, and this SDMR damper provides a higher safety factor.

Refer to the task allocating and optimization problem of distributed gas-electric hybrid control system, this paper establishes graph model of system hardware structure and application event of the distributed real-time control. The task allocation in distributed application process is abstract as mapping between those two sets. A task allocation scheme of minimum load bus is proposed from the angles of system bus and message mapping. Combined with the design of the gas-electric hybrid power system, genetic algorithm is adopted to solve the optimization problem, and the program verification and the bus analysis are carried out on the experimental bench. The test results show that the proposed scheme can satisfy all kinds of task constraints and resource constraints, the efficiency of the bus is improved, and consumption of resources is reduced.

Bridge pier collision avoidance system is a hot research topic. As the representative of the intelligent material, the Magnetorheological Grease has become one of the main research directions in the research of bridge pier collision due to its special mechanical properties and rheological properties. In this work, we present a bridge pier collision avoidance system using Magnetorheological Grease Material. Firstly, according to the characteristics of bridge pier collision, a series of Magnetorheological Grease Material are configured, and then the collision avoidance structure of the actual size of the bridge pier is given. The structure can be directly applied to the bridge pier collision avoidance. Secondly the experimental characteristics of the Magnetorheological Grease Material are given, and the experimental results are analyzed. The strong theoretical guidance and engineering basis were provided for the related scientific and technical workers and researchers.

In this paper, on the basis of the viscoelastic fractional derivative model, Mittag-Leffler function is applied to deduce the expression of stress relaxation modulus for magnetorheological elastomers according to its form and main properties. Furthermore, the relaxation modulus for polyurethane rubber matrix cured magnetorheological elastomers at different applied magnetic fields and shear strains is tested by rheometer. The results indicate that magnetorheological elastomers exhibit obvious relaxation behavior and the magnetic field strength and shear strain exert significant influence on the relaxation behavior: the relaxation modulus of magnetorheological elastomers increases with the magnetic field strength but decreases with the shear strain. Besides, the model agrees well with the experimental data which indicates that the model is suitable for characterization of relaxation behavior for magnetorheological elastomers.

The modified carbonyl iron powders with single particle size (single-grading) and binary particle sizes (double-grading) were added in the composite gel, which was prepared by using methyl silicone oil, gelatin and agaropectin colloids as raw materials, and then the single-and double-grading magnetorheological composite gels (MRCGs) were prepared by vacuum decompression. The effects of particle size and gradation of carbonyl iron power on the rheological behavior of the MRCGs were studied. The results show that the shear strength of single-grading MRCGs decreased gradually with the decrease of the carbonyl iron particle size. However that the shear strength of the double-grading MRCGs with the gradation of 90 wt% un-ball-milled and 10 wt% ball-milled carbonyl iron powders first increased then decreased with the elongation of milling time (the decrease of carbonyl iron paticle size) and reached 99.6kPa when ball milling time for 24h, which was 17.8kPa larger than that of un-ball-milled single-grading MRCGs.

In this paper, we establish the mechanical property analysis of Single-walled Carbon Nanotubes (SWCNTs) modified beam element model based on the molecular structural mechanics method. Then we study the mechanical properties of their radial direction characteristics using the finite element software Abaqus. The model simulated the different bending stiffness with rectangular section beam elements C-C chemical force field. When the graphene curled into arbitrary chirality of SWCNTs spatial structure, the adjacent beam position will change the moment of inertia of the section of the beam. Compared with the original beam element model and the calculation results, we found that the established model largely reduced the overestimate of the original model of mechanical properties on the radial direction of the SWCNTs. At the same time, compared with other methods available in the literature results and the experimental data, the results can be in good agreement.

OAPS/SiC/EP, SiC/EP, A151-SiC/EP composites were prepared and their impact properties, flexural properties, thermal conductivity and insulation and thermal stability were investigated. The comparison of three different composites showed that OAPS/SiC/EP composites had best properties. The thermal conductivity of OAPS/SiC/EP composites increased with increasing filler content. The thermal conductivity of OAPS/SiC/EP composites with 20 wt% SiC was 0.34 W/mK and was 55% higher than that of unmodified EP.

The quenching process can produce great residual stresses in 7055 aluminum alloy plates. The main factor that affects the quenching residual stresses is the heat transfer coefficient in the quenching process. In this paper, the heat transfer coefficients of spray quenching under different spray water flows were measured by using the inverse method, and the heat transfer coefficients of immersion quenching under different water temperatures were measured by the iterative method. The heat transfer coefficient increases as the spray water flow increases while decreases as the water temperature increases. The basic differences of water temperatures/spray water flows/quenching methods are the different heat transfer coefficients. According to the heat transfer coefficients results of immersion and spray quenching, an orthogonal test was carried out to study the effects of heat transfer coefficients in different temperature regions on the quenching residual stresses. The heat transfer coefficients in the range of 100oC ~200oC have a great influence on the quenching residual stresses, especially for the heat transfer coefficient near 150oC.

Fe-Ni@ SiO2core–shell structured micrometer spherical particles with nanometer thick SiO2 shell were fabricated by a facile wet chemical process, their compositions and mechanisms were investigated using x-ray diffraction and Fourier transform of infra-red spectra, and their microstructures and magnetic properties were analyzed by high-resolution transmission electron microscopy and vibrating sample magnetometer. The structure of the synthesized SiO2-coated Fe-Ni alloy particles varied with adding TEOS contents. As-prepared Fe-Ni@SiO2 composites exhibit typical soft magnetic properties. Their highest saturation magnetization approximately linear decreases from 176 emu g−1for pure Fe-Ni alloy powders to 121 emu g−1for the coated powders with 20nm amorphous silica layers, but the coercivity of all different thickness SiO2-coated Fe-Ni alloy powders maintains in the range of about 25 Oe.

This paper made the digital model reconstruction of the RB211 high pressure turban blade. First, collected rough points cloud data by using visual measuring equipment. Then, finished pre-processing the point cloud data, took the rational simplification. Finally, a new algorithm was used to reconstructing the 3D digital model. The results proved that this method improved smoothness of the model, and reduced time and cost of modeling and machining.

This paper performed a series of finite element method (FEM) simulation to investigate the influence of the tool wear on the cutting temperature in the diamond ultra-precision cutting of the aluminum alloy mirror. The two-dimensional FEM model including the diamond tool with the different average width of wear land on flank face was established. A series of ultra-precision cutting experiments using different cutting distance was performed. The tool wear was detected by scanning electron microscopy (SEM), and the cutting temperature was detected by infrared thermal imager. The comparison of the simulation investigations and the experimental investigations was done. The results revealed that the cutting temperature increases with an increase of the average width of wear land on flank face in the FEM simulation. And in the ultra-precision cutting experiments the diamond tool wear becomes severe as the cutting distance increases, meanwhile the severe tool wear results in the higher cutting temperature. Consequently the FEM simulations prove to be right.

One-dimensional Fe, Co, Ni nanotube arrays ware fabricated successfully by the electrochemical deposit in porous anodic alumina oxide (AAO) templates. The microstructure of nanotubes were observed by scanning (SEM) and transmission electron microscopes (TEM) respectively. The obtained Fe, Co, Ni nanotubes are arranged orderly. The magnetic property of nanotubes was measured and analyzed. The results show that the residual magnetization of Ni nanotubes is the biggest, and that of Fe nanotubes is the smallest. It is easy to be magnetized along the axial direction.

A plate (30mm thick) of aluminum alloy 7085-T76 was quenched into water at room temperature after solution treated at 470°C. The quenching residual stresses distributions were studied by both experimental measurement and FEM (Finite Element Method) simulation. The experimental measurement was accomplished by using the contour method, and the FEM simulation was carried out to verify the experimental results. The experimental quenching residual stress distributions showed the tensile stresses of 74.8MPa ~109MPa in the center part, and compressive stresses of 29MPa-63.6MPa on the surface. The prediction distributions showed the maximum tensile stress of 98.2MPa in the center and the maximum compressive stress of 50.5MPa on the surface. The experimental quenching residual stresses distributions agree favorably with the prediction results. The deviations of the maximum tensile stress were less than 25MPa in the center. The deviations may be attributed to the accuracy of the contour method and the idealization of the prediction model.

Four kinds of typical metallurgical waste slags were characterized with their chemical composition, crystalline phases, microstructure and thermal behavior. The heating behavior of these slags in a microwave field were also examined. The results show that there is a high content of CaO in these waste slags. When the metallurgical waste slags were heated from room temperature to 1300°C, the weight loss of Blast Furnace (BF) slag and ladle furnace (LF) refining slag are only 2.25% and 0.9%, respectively, while the weight loss of Basic Oxygen Furnace (BOF) slag and electric arc furnace (EAF) slag are more than 5%. These metallurgical waste slags have a good absorption capacity for the microwave irradiation, the absorption capacity of microwave decreases in the order of converter slag > EAF carbon steel slag > baste furnace slag. In addition, the temperature-rising rates of the metallurgical waste slags increase with the microwave power and the quality or the particle sizes of slags. Furthermore, the crystalline phases of treated slag with microwave are similar with that of the untreated metallurgical slag. A number of internal cracks in particles of metallurgical slag can be found or extended after microwave treatment.

Due to its relatively low mass density, low cost, high strength, the aluminum alloy is an ideal optical material to fabricate the large metal mirror of infrared band optical systems. The diamond ultra-precision cutting can produce ultra smooth machined surfaces without other finishing processes. Consequently, it can be used as a effective method to fabricate the large metal mirror. However, the tool wear is severe during the ultra-precision processes, which will ruduces the surface error of the large metal mirror. In this work, the ultra-precision cutting tests were performed to investigate the tool wear. The tool wear was examined by using a scanning electron microscope (SEM), and the chip was examined by using x-ray energy dispersive spectrdmeter (EDS). The tool wear mechanism and the influence of the chutting parameters on the tool wear were investigated. The results show that the daimond tool occurred abrasive wear and diffusing wear in the diamond ultra-precision cutting of aluminum alloy. The average clearance wear width increases with an increase of the cutting speed and the feed rate. There is a slight rise in the average clearance wear width as the depth of the cut increases in the range of 5μm-15μm. The average clearance wear width obviously increases when the depth of the cut reaches to 20μm.

The method of Multiple Stress Concentration Regions (MSCRs) on the surface of MEMS Silicon micro-structure is introduced in order to enhance the sensibility of the hair vector hydrophone without reducing the working bandwidth. The MSCRs with the thickness and width smaller than the rest of the cantilever can produce localized stress concentration when constant force is applied on the structure. ANSYS software has been used as a tool to analyze the effect of different shapes and dimensions on the performance of the micro-structure. The optimum MSCR has been obtained. Results show that compared with the ordinary structure, the sensitivity of the micro-structure with MSCR can be increased by 1.5 times, and the upper limit of bandwidth can be improved from 337Hz to 500Hz. This paper provides a new method to resolve contradiction between the sensitivity and working bandwidth.

A Re-containing single-crystal superalloy was processed with conventional radiation high rate solidification (HRS) and liquid-metal cooling (LMC) techniques, respectively. Compared with the HRS castings, LMC castings exhibited the greatly refined dendrite structures and lower segregation. At the withdrawal rate of 50 μm/s, the primary and secondary dendrite arm spacing of LMC casting was 103 and 19 μm, which were reduced by 60 % and 53 % compared to the counterpart of HRS castings. Moreover, higher withdrawal rates significantly shortened the characteristic diffusion distance and reduced the residual segregation of refractory elements after homogenization-solution treatments, which is beneficial for improving the local phase stability of Re-containing superalloys.

In this paper, the microstructure and mechanical property of the Al-Zn-Mg-Cu aluminum matrix composite reinforced by SiC particles with the contents of 2.5, 4.5, and 6.5wt% through vacuum casting are studied. The homogenization treatment was conducted at 465°C heat insulation for 24h. The purpose of this study is to analyze hot extrusion influence on the microstructure and hardness of the Al-Zn-Mg-Cu aluminum matrix composite. SiCp under pre-processing possesses good wetability with the analysis of Laser Particle Sizer and XRD. Metallurgical microscope, XRD, SEM and EDS is applied to analyze the microstructure of the Al-Zn-Mg-Cu aluminum matrix composite. It has proved that the hot extrusion can effectively improve the homogenization of SiCp and dissolve the second rough phases to reinforce the dispersal of CuAl2and MgZn2phase. The hardness of Al/SiCp composite rises as the increase of the SiCp content. It is shown that when the SiCp content is above 5%, its hardness obviously reinforced as well as that of the Al/SiCp composite.

Oxidation behavior of FGH91 superalloy in air and the temperature range of 540 to 980 °C for period up to 100h has been studied. The results indicate that oxidation kinetics obeyed parabolic law, and the activation energy of oxidation was calculated to be 98.2 KJ/mol. The scales on the surface were determined by SEM, EDS and XRD, the results show that the oxidation scales were composed of three layers: the outer layer was composed of Cr2O3 layer with a small amount of TiO and NiCr2O4 spinel; the intermediate layer was made up of Al2O3 and matrix alloy; and a small amount of titanium-nitride disperse in the inner layer. Besides, γ’-free layer was formed under the oxidation scales due to the impoverishment of Al in this layer, which was induced by the formations of Al2O3.

The reinforcement of expansive soil cutting slope has been a difficulty for the construction industry. This study selected Wanyi Expressway as the construction background and used finite difference method for the numerical simulation and design optimization of expansive soil cutting slope reinforced by sash girder anchor bolts. Calculation results show that the cutting slope ratio is closely related to the stability of the expansive soil cutting slope and that the length, set angle, and vertical spacing of the anchor bolts significantly influence the deformation of the cutting slope. The original design plan was optimized according to the calculation results, and a positive effect in plan execution was achieved. This study may serve as a reference for other similar construction designs.

Different particle size range of waste glass powder amount to replace part of the cement made to mortar specimens, which were soaked in 5% sodium sulfate solution and water after standard curing .Then determining its mechanics properties in various ages, observing and analysis of the micro structure of the section of the specimens by SEM, exploring the ability of mortar specimens made in different size and dosage of waste glass resist to sulfate. The results indicate: Along with the rising of the size and content of glass powder. The performance of mortar specimens resisting to sulfate were on the decline. When replacement amount was 10%, all kinds of particle size of waste glass mortar specimens are better than that of ordinary Portland cement on mechanical properties, When the glass powder size is less than 53μm, all kinds of mortar specimens with high content of waste glass are better than that of ordinary Portland cement on mechanical properties.

With advances in data collection and generation technologies, environments that produce data streams is more and more. In recent years, the network application is further universal and the applications of a single data stream transfer toward a multi-node distributed data streams, such as sensor network, network monitoring, web log analysis and the credit card transaction data of multiple sites. These data is not only real-time, continuous and large scale, but also distributed. How to manage and analyze large dynamic datasets is an important subject that researchers are faced with. In view of the situation, it presented the formalization description of homogeneous and heterogeneous distributed data stream in this paper, analyzed advantages and disadvantages of the centralized stream processing architecture and distributed streaming processing architecture, discussed the recent progress in distributed data stream classification algorithm, summed up the problems and challenges faced by the distributed data stream mining, and possible future research directions.

Intake port is an important part of the gasoline engine, its structure will influence the gas flow characteristics which directly affects the performance of the engine [1]. In this paper, three-dimensional CFD calculation and structural optimization were used to research the performance of gasoline engine. Firstly, the method of laser scanning and UG software were used to reverse modeling engine exhaust port and get the three-dimensional model. Secondly, after setting boundary conditions and turbulence models, the air flowing through the intake ports were simulated by FLUENT software respectively. Finally, based on numerical methods, the pressure field, velocity field were shown. The results of the simulation of flow field characteristics analysis show that the simulation and experimental results are in good agreement.

Exhaust passage is a significant part of the gasoline engine, its structure will affects the gas flow characteristics of the engine directly [1]. So, research and analysis of the exhaust tract is essential. In this paper, a detailed analysis of the flow field under cold state and hot state was made. For a start, the method of laser scanning and UG software were used to reverse modeling engine exhaust port and get the three-dimensional model. The next, the unstructured grid with local mesh refinement scheme was used to mesh this three-dimensional model with ICEM. After this, numerical simulations of the exhaust passage with five different valve lifts were carried out under thermal and cold conditions. Finally, comparing the velocity field and pressure field of the exhaust passage under cold state and thermal state, it can be find that the flow field under hot and cold state have similar characteristics. The results of this paper can provide a theoretical basis for following researches of the engine exhaust port.