bluuebunny/crossref_metadata_2025 huggingface dataset:
Intelligent Health Monitoring System for a Railway Cable-Stayed Bridge
Authors: Shan De Shan , Yan Peng , Wang Zhen Hua
Published: November 2010

Intelligent health monitoring system of the long-span railway cable-stayed bridge requires the comprehensive knowledge of instrumentation, analytical and information processing technologies with the knowledge and experiences in design, construction, operation and maintenance of railway cable-stayed bridge for long-term monitoring the performance throughout its lifecycle. It is necessary to perform sensor-based structural monitoring for identifying the bridge conditions in order to assure the structural safety and to evaluate the operational performance. The considerations for deploying a proper monitoring system are appropriate sensor instrumentation, robust signal acquisition, reliable signal processing, and intelligent signal and information processing. The experience on developing an autonomous monitoring system in the one certain railway cable-stayed bridge newly constructed is introduced in this paper. Sensor and hardware instrumentation, signal transmission, signal acquisition and analysis are schematically described mainly. Experience through this work will be worthwhile lessons for other similar efforts.
Synthesis, Characterization and Properties of Poly (ε-Caprolactone) Glycol Based Casting Polyurethane Elastomers Containing Nano-Size Sio2 Particles
Authors: Chen Xiao Dong , Ma Tie Jun , Zhang Hai , Chen Rong Sheng
Published: November 2010

Poly(ε-caprolactone) (PCL) glycol based casting polyurethane elastomers (CPUE) filled with nano-SiO2 particles within different surface properties were synthesized by mean of in-situ polymerization. The macro-static/dynamic mechanical properties and micro-dispersed state were characterized by an electronmechanical universal testing machine, a durometer, a rubber resilience experimental machine, a dynamic-mechanical analyzer (DMA) and a scanning electron microscope (SEM). The tensile modulus at 100% and 300%, elongation at break, tensile strength and tear strength of PCL urethane nanocomposites increased substantially in the presence of a certain amount of nano-SiO2 compared with their pristine state. Furthermore, the tensile strength and tear strength at 100 of the PCL CPUE with 5% nano-SiO2 pretreated by γ-glycidochloropropyl methyl trimethoxy silane (SI-CA) were 1.50 and 1.94 times than those of the pure PCL CPUE, respectively. The addition of the nano-SiO2 had little effect on the hardness, but the impact resilience decreased slightly. DMA analyses showed that the loss factor peaks of two nano-SiO2 polyurethane composites were higher obviously than the pure PCL CPUE and the glass transition temperature （Tg）of the two nano-SiO2 polyurethane composites increased to higher temperature region. SEM fractographs showed that the surface treatment by the optimum silane coupling agent influenced the dispersibility of nano-SiO2 in the PCL CPUE distinctly. The agglomerating phenomenon, and even some nano-agglomerates with more than 1 μm diameter can be observed in the PCL CPUE with 5% untreated nano-SiO2, but the nano-SiO2 pretreated by SI-CA was dispersed in the PCL CPUE in nano-scale.
A Low Temperature Precursor Sulfuration Route to Metal Sulfides Nanomaterials
Authors: Zhang Ya Hui , Cheng Xi , Wang Qing
Published: November 2010

A low-temperature precursor sulfuration route has been established to prepare metal sulfides with different nanostructures during the synthesis of nickel sulfide. The advantages of the low-temperature precursor sulfuration route were testified by the synthesis of different metal sulfides ( lead sulfide, zinc sulfide and cobalt sulfide). It offers a novel path to the preparation of other metal sulfides.
Preparation of Cu-Zn Alloy by High Energy Ball Milling of Elemental Copper and Zinc
Authors: Wang Kai Jun , Cai Xiao Lan , Wang Hua , Hu Jin
Published: November 2010

Cu-Zn alloy was prepared by high energy ball milling of elemental copper and zinc, With the Simoloyer attrition mill the particle around 10µm with good particle-size distributions can be made in 100 min. Through the analysis by TG-DTA, XRD, SEM, the results show that Cu-Zn alloys can be produced by ball milling without the formation of oxide even milling in the air atmosphere and subsequent heat treatment at 350°C, it indicated that the formation of the oxide can be avoided during ball milling by adding Al.
Effects of Synthesis Parameters on Hydrothermal Synthesis of NaA Zeolite
Authors: Yuwen Lin Lin , Zhu Meng Fu , Su Hong Bo , You Xiu Dong , Deng Cheng , Lü Xiao Long
Published: November 2010

In this research, NaA zeolite samples were synthesized from aluminosilicate solution through hydrothermal method. The effects of different parameters such as the SiO2/Al2O3, OH-/Si and H2O/Na2O molar ratios of the initial gel solution, crystallization time and temperature on the crystallinity and morphology of the synthesized zeolites were investigated. The final products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and laser particle size analyzer. The experiment results indicated that the SiO2/Al2O3 molar ratio had influence on morphology and size of the synthesized zeolites, the optimum range of SiO2/Al2O3 molar ratio for synthesizing NaA zeolite was 1.5-2. Alkalinity (OH-/Si and H2O/Na2O molar ratio) had a significant effect on particle sizes of the synthesized zeolites, the higher the alkalinity, the smaller the crystal particle size. In addition, it was found that crystallization temperature during hydrothermal treatment played an important role in reducing the over all reaction time. The crystallization time had effect on the crystallinity of the synthesized zeolites. Finally, the optimum synthesis parameters can be proposed in order to synthesize NaA zeolite with desirable particle size, crystallinity and morphology.
Synthesis of Nanosized Ag0.9Na0.1(Nb0.7Ta0.3)O3 Ceramic Powder and Investigation on its Property
Authors: Yan Yu Qing , Wen Yu Gang
Published: November 2010

In this communication, Ag0.9Na0.1(Nb0.7Ta0.3)O3（ANNT） mixed oxide powder was synthesized by citrate wet chemical method. TG-DTA, XRD and TEM analyses showed that the reaction temperature was 800°C, the calcining time was three hours, and the product was pure ANNT in well-dispersed grain structure (35nm in average).
Water Disinfection Using Fe3+ and N-Doped 3SnO2/TiO2 Thin Films Coated on Glass Fibers
Authors: Sikong Lek , Kongsong Peerawas , Rachpech Vishnu
Published: November 2010

The water disinfection efficiency of Fe3+ and N-doped 3SnO2/TiO2 composite and undoped films was investigated. The water containing E. coli with an initial concentration of 103 CFU/ml was treated by a photocatalytic reactor filled with 60 g of glass fibers coated with the catalytic films for 1-5 circulated cycles. The number of survival bacteria after treatment was evaluated with spread plate techniques. Furthermore, the photocatalytic reaction on degradation of methylene blue dye solution was also investigated in order to observe the correlation between the result of bacteria inactivation of the prepared films and that of photocatalytic activity on methylene blue degradation. It reveals that N-doping in the TiO2 composite films results in shifting absorption wavelength towards visible light, narrowing the energy band gap and acts as photo-generated electrons trapping site, leading to retardation of the electrons-holes recombination, while Fe3+ doping has a main effect on hindrance of anatase crystal growth of the composite films. Therefore, 20N/3SnO2/TiO2 composite thin film exhibits greater photocatalytic activity and disinfection efficiency than those of undoped and Fe3+ doped TiO2 films. It was found that the bacterial inactivation of the prepared films correlates closely to photocatalytic activity performed by degradation of methylene blue dye solution. The 20N/3SnO2/TiO2 composite film can kill E. coli 97% within 5 cycled water treatment (~93 min) while Fe3+/3SnO2/TiO2, undoped TiO2 and UV alone can kill only 62, 65 and 58%, respectively. The 20N/3SnO2/TiO2 films coated on glass fibers are expect to be applied as an antibacterial photocatalyst for water purification.
Preparation and Application of Slag Compound Flocculant
Authors: Li Shan Ping , Yang Wei , Fu Jing
Published: November 2010

A new kind of composite flocculant, polyaluminum ferric chloride (PAFC), was prepared using blast furnace dust and scrap material of aluminum. Tests about its application on the treatment of brewing wastewater were carried out and the flocculation mechanism was discussed. Results showed that the best condition for foluccation was: doses of PAFC was 40 mg/L, pH of wastewater was about 7.0, sedimentation time was 30 min, removal rate of turbidity, CODcr, decolorization and ammonia were 96.8%、64.7%、87.5% and 41.0% respectively.
Fabrication of the Ordered and Sandwich Structured Polyaniline/Graphene Nanoarrays
Authors: Hao Qing Li , Tian Jiao , Wang Hua Lan , Wang Xin
Published: November 2010

The ordered polyaniline nanoarrays had dispersed homogeneously on the graphene oxide or reduced graphene oxide sheets without agglomeratation in isopropanol media. The composites were characterized by field emission scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, Raman spectroscopy and electrochemical tests. The electrochemical performance of the electrode material had been dramatically improved with the highest specific capacitance of 1351 F/g.
Synthesis and Characterization of Li-Ti-O Nano-Composites and Their Doped BaTiO3 Based X7R-Type Ceramics
Authors: Zhang Qing , Niu Rui Yuan , Wang Min , Cui Bin , Chang Zhu Guo
Published: November 2010

Li-Ti-O (abbreviated as LTO) nano-composites were synthesized via sol-gel process, and then doped BaTiO3 based X7R type ceramics. The LTO nano-composites and their ceramics were characterized by means of thermaogravimetric, Fourier-transform infrared, X-ray diffraction methods, transmission electron microscopy. We also characterized the dielectric properties of the LTO doped BaTiO3 based ceramics of X7R type. The results indicated that LTO nano-composites were nanometer scale powders. The pH value and calcining temperature had an influence on particle size of LTO sintering aids. At pH about 3 and with calcining at 600 °C, the nano-composites attained minimum particle size (about 10 nm). By adding 0.10 wt% of the LTO nano-composites, the temperature permittivity achieved about 4200 when sintered at 1240 °C for 4 h, and the dielectric properties met X7R standard.
Facile Synthesis of Hydroxyapatite Nanorods with Controlled Sizes and Morphologies
Authors: Lv Sha Sha , Wang Ning , Li Gui Cun , Peng Hong Rui
Published: November 2010

High quality hydroxyapatite (HAP) nanorods have been synthesized at 180 °C by a facile hydrothermal method using calcium chloride and diammonium hydrogen phosphate as precursors in the absence of any surfactants. The diameters and lengths of HAP nanorods are in the range of 40-80 nm and 0.2-2.0 μm respectively. The sizes and morphologies of HAP nanorods can be controlled by adjusting the synthetic parameters, such as reaction temperatures, and types of surfactants. A possible mechanism was also proposed to explain the growth of the HAP nanorods.
The High Thickness Ni Layer on Single-Walled Carbon Nanotubes Prepared by an Electroless Coating Process
Authors: Li Wei Xue , Wang Dun Dong , Jin Hui , Dai Jian Feng , Wang Qing
Published: November 2010

The Single-walled carbon nanotubes were coated with Ni-P layers by an electroless plating technique. A Ni-P layers are thick and smooth and on individual nanotube with thickness of 20 nm can be obtained after the deposition process. The Single-walled carbon nanotubes were obtained in the suspension of purification solution. The samples have been characterized by X-ray diffraction, selected area electron diffraction, transmission electron microscopy and energy dispersive spectrometry.The coating layers after heat-treatment convert the amorphous Ni-P coated layers into the nanocrystalline Ni-P layers.
Fiber Bragg Grating Temperature Sensor System on a Twin-Deck Continuous Rigid Frame Bridge for Long Term Monitoring
Authors: Wang Lei , Li Dong Sheng , Ou Jin Ping
Published: November 2010

In structural health monitoring, evaluation of bridge serviceability performance is based on vibration method. The vibration properties are influenced by temperature, humidity, wind and traffic load. Temperature differential in rigid frame bridge causes additional stress, which affects dynamic characteristics and induces concrete cracks. Thus analysis of temperature distribution is the basement of damage identification. Fiber Bragg grating (FBG) sensors are advanced materials for SHM. This paper introduces a temperature sensor monitoring system consisting of 52 temperature sensors on a twin-deck continuous rigid frame concrete bridge and analyzes temperature distribution on the twin decks of the bridge through August to December, 2006. Temperature at the same height sections differs little in the longitudinal direction along this bridge. The comparisons between maximum and minimum temperature each month reveal the asymmetry of transverse temperature distribution. The pavement has significant impact to the top slab temperature. In November the temperature declines sharply. The temperature on the external surface of top slab is lower than that of bottom for short box girders in winter because of shelters of flanges.
Analysis of Cylindrical SMA Fan Clutch
Authors: He Jian Min , Huang Jin , Liu Yu Xi
Published: November 2010

This paper presents a cylindrical Shape memory alloy (SMA) fan clutch for automobile cooling system application. The resilience of pre-strain 2% SMA alloy wire is analyzed in the processes of heating and cooling. The Design method of SMA helical spring is described. The expression of transmission torque provided by SMA spring is established. The relationship between transmission torque and temperature is analyzed in detail. The results indicate that the transmission torque increases gradually with the increasing of airflow temperature and decreases with the decreasing of airflow temperature, respectively. The cylindrical SMA fan clutch has the property that its transmission torque changes rapidly according to the temperature of airflow from radiator.
Effects of Welding Chamber Step on Extrusion Process of a Complex Hollow Profile
Authors: Chen Hao , Zhao Guo Qun , Zhang Cun Sheng , Liu Jiang Wei
Published: November 2010

The extrusion die is of great importance in the quality control of profile production. Yet in practice, the design of extrusion die is mainly dependent on the experience and intuition of die designers, which is difficult to guarantee product quality and productivity. In this paper, a numerical model was developed based on HyperXtrude with an attempt to investigate the effects of the shape of the welding chamber on metal flow and weld quality. The porthole dies with different steps of welding chamber were designed and applied to extrude an identical profile. Numerical results showed that with an increasing step of welding chamber, more uniform velocity and temperature distributions in the cross-section of the extrudate were observed. In addition, the weld quality was improved owing to increasing welding pressure, when adopting the multi-step welding chamber.
Effects of the Parameters of Friction Stir Processing on Silicon Particles and Hardness in Hypereutectic Al-Si Alloys
Authors: Lu De Hong , Wei Shao Sheng , Zhou Ming , Jiang Ye Hua , Zhou Rong
Published: November 2010

Friction stir processing (FSP) was applied to modify the surface of a hypereutectic Al-30wt.%Si alloy, the influence of the parameters on the size and morphology of Si particles, the microhardness of the mateials in the stir zone was investigated. All samples were preheated to research the influence of the pure heat input on Si. With the preheating temperature increasing from 100°C to 400°C, the average diameter increases gradually, but the shape factor decreases, the microhardness of the materials decreases. With the rotation rate increasing from 375rpm to 1050rpm, both the average diameter and shape factor increase, but the microhardness decreases. With the FSP passes increasing from 2 to 6, the average diameter decreases, and both the shape factor and the microhardness increases. Linear regression lines in most cases are presented to reveal the quantitative relationship between the FSP parameters and the Si particles and the microhardness. The reasons of the refinement and the spheroidization of the Si particles are carefully discussed. The microhardness variation of the materials is attributed to the size change of the Si particles with the FSP parameters.
Grain-Refining Mechanism of Heavy Cold-Rolling of Lath Martensite
Authors: Zhao Xin , Yang Xiao Ling
Published: November 2010

This paper analyzed the microstructure evolution and grain-refining mechanism in producing ultra-fine grained steel sheet by heavy rolling of lath martensite. The results show that this technique is composed of three processes with different grain-refining mechanism respectively: i) austenite grains subdivide into homogeneous and tiny martensite laths during quenching; ii) martensite laths are thinned and damaged during heavy rolling; iii) equiaxed ultra-fine ferrite forms during low temperature recrystallization annealing.
A Review on Fabrication Methods of High-Quality Graphene Nanoribbons
Authors: Zhang Hui Liang , Zhang Chun Yuan , Shi Ding Ding
Published: November 2010

Three different fabrication methods of graphene nanoribbons are discussed. Graphene nanoribbons can be produced through unzipping the carbon nanotubes and also cutting graphene sheets, but with rough edges. Another method is a simple, surface-based bottom-up chemical method without the need for cutting, resulting in high-quality graphene ribbons. The band gap of a graphene ribbon strongly depends on its geometry, particularly its width. The third method creates easily graphene ribbons with different width.
Friction Property of HDPP Modified with Talc under the Dry Friction Condition
Authors: Chen Nan Chun , Deng Ai Ping , Cheng Peng , Wang Wei
Published: November 2010

: The talc with average volume grain of 5.35 µm was modified by the mixture of HDPP as bases, grinding talc as the reinforecing filler and proper quantity of coupling agent. After blending the mixture of coupling agent of 1.7 (wt) %, different mass ratio of talc among 4~14 (wt) % and HDPP, the characteristics of surface modification was performed on electron microscopy and the friction properties grinding against stainless steel was analyzed on abrasion and wear tester of M-2000 type under dry sliding condition. The results show that the friction rate of composites is 1.909*10-5 with lower abrasion proof rate, and the friction coefficient is 0.147 with better friction resisting property when the content of talc is 8%. In this way, it can offer comparable data for fiber and other areas.
Slurry Preparation: A Key to Upgrade CMP Efficiency
Authors: Zhang Chao Hui , Lei Hong , Hu Xiao Li
Published: November 2010

Slurry preparation is of paramount importance in chemical mechanical planarization (CMP) process. It couples the combination effects of chemical and mechanical ones. In this paper, the characteristics of the slurry particles used in CMP are firstly modeled, which includes the size and the concentration with primary priority. And then, the model is validated by experiments during hard disk wafer polishing. The slurry prepared contributes to a high quality hard disk surface processed with CMP, which leads to low waviness Wa and roughness Ra with suitable material removal rate (MRR) as well. The study will surely lay a feasible foundation to the CMP mechanism.
The Effect of Calculating Gridding Size on the Formation of Multimode Penetrator
Authors: Li Wei Bing , Wang Xiao Ming , Li Wen Bin , Zheng Yu
Published: November 2010

Aim at the problem of Ansys/LS-DYNA software simulating in the shaped charge modeling, this paper studies the influence of calculating gridding size on the multimode penetrator forming. It can be found that when the gridding size is 0.028 times the charge caliber or less, the formation of penetrator can be good with the trail result. It obtained the change curve of the model nodes and the calculating time of certain computer with the size of gridding. When the gridding size is from 0.022 to 0.028 times the charge caliber, the model nodes diminish 30.8%, and the calculating time decreases 42.9%. It obtains the effects of calculating gridding size on the multimode penetrator formation parameters, such as velocity and length-diameter ratio. The simulation results were validated through X-ray imaging experimentation. Both results are in good agreement.
Research on the Prediction Model of Laser Surface Hardening Index on Cylinder Liner Based on RBF
Authors: Wu Xiao Ling , Ren Fei
Published: November 2010

Based on the data obtained from the perpendicular experiment of laser surface hardening on HT150 cylinder liner of a certain motor engine, a Radial Basis Function (RBF) neural network prediction model of laser surface hardening index about HT150 cylinder liner is established by Matlab neural network toolbox in this paper. The parameters of input layer are affirmed by analyzing influential factors of the hardened index ,and the best form of the network is affirmed by selecting suitable spread in function-newrb( ),and as a result, the prediction accuracy and the adaptability of the network are improved. The result of testing the model indicates that the model based on RBF neural network has a good generalizing capability. Compared with traditional Back-Propagation Network (BP network), the result indicates that RBF has better accuracy and adaptability.
Improving the Qualified Rate of Coloring Inspection about the Bevel Gear in Centrifugal Ventilator by Applying Six Sigma Methodology
Authors: Cao Yang Hua , Xie Shu
Published: November 2010

The low qualified rate of coloring inspection about the bevel gear had puzzled the producer for a long time. This paper tried to solve this problem by applying 6σ methodology. It analyzed the influence factors about the qualified rate of bevel gear coloring inspection and found out the main influence factors firstly; then on base of the analysis results, this paper proposed some improvement measures by applying the DOE analysis; finally, this paper validated the effects of these improvement measures by carrying out some tests. The improvement measures proposed in this paper had improved the qualified rate of coloring inspection obviously.
Experimental Investigation on Determinant of Steel Specimen Transformation Temperature under Air Cooling Conditions
Authors: Chen Lian Sheng , Wang Tao , Song Jin Ying , Liu Yi , Liu Zhen Yu , Liu Xiang Hua
Published: November 2010

In order to get rid of thermal interferences, the experiment was conducted to test the temperature drops of 40Cr by embedding thermocouple in central part of the steel specimen under the air cooling conditions. The cooling rate of the center was obtained and the phase transition temperature at the start and end points were determined. By comparing with 40Cr CCT curves, obvious effects of the metal phase transition latent heat on cooling rate were shown. The results should be revised when CCT curves which obtained form constant-speed cooling rate conditions were used to determined phase transition start and end temperature in non-constant cooling rate conditions.
Quantitative Evaluation on Influence Factors of IC Chip's Image Characteristics Based on Fuzzy Gray Theory
Authors: Liang Zhong Wei , Zhang Chun Liang , Wang Yi Jun , Deng Hong Guang
Published: November 2010

For the purpose of acquiring IC micro-topography accurately, fuzzy gray theory is used for quantitative evaluating the influence factors of IC chip’s image characteristics. Through selecting different influence factors in the process of image acquiring and establishing the factor-parameters array, a mathematical model of fuzzy gray evaluating system is structured. After calculating the fuzzy gray relational degree between the factor-parameters and the image characteristics, the external influence on image is quantized. By experiment and comparison the relational degree is quantitative analyzed and the influence tendency is chart-illustrated, thus research conclusions and referential suggestions are reached. It provides theoretical foundation and technical preparation for IC image sampling condition’s selection and adjustment.
Multi-Component Gas-Liquid Equilibrium for Hydrogen Production from Glucose Gasification in Supercritical Water
Authors: Yan Qiu Hui , Liu Ju , Wang Bei Bei , Li Gui Xia
Published: November 2010

A high-pressure absorption method can realize separation of H2 from CO2 since they have different solubility in high-pressure water. The gas-liquid equilibrium model of hydrogen production from glucose gasification in supercritical water based on the modified SAFT model and SAFT equation of state was developed to predict the effect of absorber’s pressure on the molar fraction of product gases in gas phase, absorption rate in liquid phase and gas yield. It was found that molar fraction of H2, CH4 and CO increased with the increasing pressure, while molar fraction of CO2 decreased. It indicates that higher pressure facilitate purity of H2. But H2 yield reduces from 0.00736mol to 0.00332mol while pressure increases from 0 MPa to 20MPa. It demonstrates that higher pressure can reduce gas yield. As a result, the purity and gas yield of H2 should be considered simultaneously for selecting proper pressure. Additionally, it is difficult to separate H2 from CH4 and CO using the high-pressure absorption method. This work is very useful for process design, development and optimization of biomass gasification in supercritical water.
Estimation of Bed Load Transport Rate Based on Grain Froude Similarity Considering the Existence of Sand Waves
Authors: Wei Bing Qian , Xun Hong Yun , Sun Xiao Jun , Xiao Rong Ge
Published: November 2010

It is very important for reservoir management to estimate the sedimentation amount deposited in a reservoir. Firstly, the formula for estimating the bed load transport rate in the bed of sand waves of prototype by model experiment was derived based on the similarity of grain Froude number; Secondly, several model experiments that the bed forms is similar with the prototype were carried, and the formula was verified. As a result, when the ratio of grain diameter in the prototype and model is great enough, and the bed forms in the model is similar with that in the prototype, a satisfactory result can be obtained by using the estimation formula for estimating the bed load transport rate of the prototype that sand waves occur in the bed.
The Design of Bending Parts Compound Die
Authors: Nie Fu Rong , Li Hong Wei , Li Yao Hui , Yang Li Li
Published: November 2010

Through analyzing U type bending parts that has bottom-holes, a suitable Compound die that can complete 4 procedures - lancing, bending , punching and be cut off at in the same forming-position was synchronously designed. The die working process and the main points of the design are introduced here. Production testing confirmed that there were different levels of improvements in the product quality, production efficiency and economic efficiency. In order to meet the design and development requirement of the die, the proportion of the compound and progressive dies in the dies production has been increased in consideration of the structure and production costs of the die.
Preparation of Suspended Liquid Hardener for No-Bake Phosphate Binder Sand
Authors: Shang Hong Fei
Published: November 2010

In order to solve the problem that powder hardeners for no-bake phosphate binder sand cause powder pollution, preparation of suspended liquid hardener has been studied in this paper. Orthogonal array L9(34) was selected to arrange the experiment. Under every factor and level an experiment was done, and suspension rate after four hours of the suspended liquid hardener was taken as experimental target. Results show that the addition of suspension agent and interaction between vector and suspension agent are significant factors at significance level α = 0.05. The best scheme is the one which contents 500g powder magnesia, 500g industrial alcohol vector and 20g SN suspension agent.
Effect of Contact Interface Pressure on Higher-Order Harmonic Wave and Bond Strength
Authors: Li Zhan Hui , Wu Yun Xin , Long Zhi Li
Published: November 2010

The model of ultrasonic propagation at a solid-solid contact interface was established. Higher-order harmonic wave generation and waveform distortion take place when the ultrasonic wave propagation at the solid-solid contact interface. Aluminum wire bond experiments were performed on a laboratory test bench. The relation of bond strength, nonlinear coefficient and contact interface pressure was studied. The experiment results show that when contact interface pressure is less than 6 kPa, higher-order harmonic wave component and the nonlinear coefficient decrease and bond strength increases with contact interface pressure increasing, when contact interface pressure is in range of 6 kPa to 10 kPa, higher harmonic wave and the nonlinear coefficient is the least and bond strength is the highest, however, when contact interface pressure is more than 10 kPa, the nonlinear coefficient increases and bond strength decreases with pressure increasing. The nonlinear coefficient of ultrasonic is a method of forecast bond strength.
Research on Mathematical Model of Leveling Process for Plate Mill
Authors: Cui Li , Hu Xian Lei , Liu Xiang Hua
Published: November 2010

In order to calculate the parameters of roller leveling process, the 3D mathematical models of plate leveling based on the curvature integral by elastic-plastic differences were set up. The calculation results by the models showed a good correlation with the measured data from a plate mill which adopts the advanced control system by SMS. The analytic models can be developed which analyzed the leveling process so efficiently that it can be used for process controlling. Additionally, the plastic deformation ratio was analyzed which can account for the leveling phenomenon, and the model was regressed which can be used easily for engineering calculation.
Computation and Analysis of Unbalancing Responses of High Speed Machining Tool System
Authors: Shen Chun Gen , Wang Gui Cheng , Wang Shu Lin , Nie Wen Wu , Liu Gang
Published: November 2010

In this study, an integrated methodology combining computational modal analysis, experimental modal analysis, and computational dynamic analysis was developed to investigate unbalancing dynamic responses of high speed machining tool systems. A linear-elasticity formulation based on the finite element method (FEM) was employed to compute the natural frequencies and obtain the corresponding modal shapes. Experimental modal analysis was then performed to verify the natural frequencies. After the validation, the FEM model was further modified to predict the dynamic responses, with an HSK (a Germany abbreviation of Hohl Schaft Kegel) tool system as a model system. The results indicated that, by validating the computed natural frequencies with experimental ones, an effective simulation model can be established for predicting complex dynamic response of high speed machining tool systems.
Fabrication of Cu-Al2O3 Composites by Simplified Internal Oxidation Process
Authors: Tian Bao Hong , Xia Cheng Dong , Jia Shu Guo
Published: November 2010

Cu-Al2O3 composites were prepared by a new simplified internal oxidation process integrating with powder metallurgical process, and then the hot extrusion and the cold rolling processes were carried out. The microstructure, electrical conductivity, hardness, tensile strength and thermal stability of the composites were investigated. The results show that Cu-Al2O3 composites were fabricated successfully by the simplified process in which internal oxidation completed during the sintering. There are a mass of fine Al2O3 particles in size varying from 5 nm to 20nm dispersed in copper matrix after sintering 950 for 4h. After sintered at 950 for 4h and extruded at 950 followed with the cold deforming of 80%, the electrical conductivity, hardness, tensile strength and softening temperature of composite reach 81％IACS, 137HV, 561MPa and 850 respectively. It is considered that the dispersion strengthening and strain hardening have greatly contribution to the Cu-Al2O3 composites fabricated with the simplified process.
Grey Model Based Particle Swarm Optimization Algorithm for Fatigue Strength Prognosis of Concrete
Authors: Liu Qin Ming , Dong Ming
Published: November 2010

This paper explores the grey model based PSO (particle swarm optimization) algorithm for fatigue strength prognosis of concrete. First, depending on concrete’s testing status, fatigue life is studied. Then, one GM(1,1) based PSO algorithm is used in fatigue strength prognosis of concrete. One important advantage of the proposed algorithm is that only fewer data is in need for fatigue strength prognosis. Finally, a case study is given to illustrate effectiveness and efficiency of the proposed approach.
The Superplastic Deformation and Microstructural Analysis of Fine-Grained 1420 Al-Li Alloy
Authors: Zhang Yan Ling , Guo He Ping , Li Zhi Qiang
Published: November 2010

The superplasticity of fine-grained 1420 Al-Li alloy which was prepared by two-stage aging and turning rolling process was studied by constant-strain-rate tensile test. The results showed that: good superplasticity was attained at temperature range of 460°C~520°C and deformation strain rate 1×10-4s-1~5×10-3s-1. An elongation of 650% was obtained at the temperature of 650°C and strain rate of 1×10-4s-1. Furthermore, the microstructures of material before and after deformation were examined using OM and TEM. Equiaxed grains were still kept, and the second-phase particles and dislocations were observed in the deformed samples.
Investigation on Micro Defects of the Protective Coating SiOx in Mass Manufacturing Processes
Authors: Wang Rong , Li Li Sha , Gao Jin Yue , Cui Hai Ning
Published: November 2010

A transparent hard coating of silicon oxide (SiOx) deposited by using plasma enhanced chemical vapour deposition (PECVD) can protect the surfaces of plastics and metals. This coating has good adhesion, good wear-resistance and environmental resistance. Our work is to optimize this protective organosilicon film in an industry manufacturing process for the metal cover of mobile phones and plastic lenses. Investigation of the failures of the film and analysis of the defect in deposited films by means of the optical microscope and atomic force microscope (AFM) shows that mechanism of the micro defect with Newton color rings.
Laboratory Evaluation and Application of New Materials Based on Mud Cake to Agglomerated Cake (MTA) Method
Authors: Gu Jun , Li Xin Hong , Liu Hao Ya , Gao Yu Tang
Published: November 2010

In order to solve the interlayer channeling in the process of oil and gas production, the forming agent of agglomerated cake and mud cake modifier based on Mud Cake to Agglomerated Cake (MTA) method are developed. The evaluation results in laboratory show that the bond strength of cement-formation interface (BSCFI) with the new materials increases significantly with curing time by comparison with those without new materials. The analysis shows that the mechanism of new materials includes three steps. Firstly, the forming agent of agglomerated cake modifies and treats the surface of mud cake and it reacts primarily with the mud cake modifier. Secondly, the cement generates in agglomerated cake. Lastly, the compact agglomerated cake forms. Field applications show that the high quality rate and qualified rate of well cementing with the new materials increased by 13.01 percent points and 1.15 percent points respectively, and the proportion of isolation section length whose Bond Index is greater or equal to 0.8 with the new materials increased by 15.92 percent points compared with other wells in the same block.
Flame Retardancy of Wood Treated with Metaborates by Double-Diffusion Method
Authors: Li Gui Fen
Published: November 2010

Wood was treated by double-diffusion method to form the precipitates of metaborates in wood. Their leachability in running water was evaluated. The precipitates of these metaborates in the wood proved to be insoluble or hardly soluble in water by the leaching test, and the best leachability for that by double-diffusion treatment with Pb2+ solution. Their flame retardancy was evaluated by limiting oxygen index (LOI) and cone calorimeter. The resultant data showed that their flame retardancy and smoke suspension were increased by the double-diffusion treatment and the best for that by the treatment with Zn2+ solution.
Production System Optimal Operation Model Based on Large-Scale System Theory
Authors: Wang Zhi Guo
Published: November 2010

For the disadvantage of traditional production mode, an operation optimization model is put forward on the basis of analyzing workshop production system operation. The Features of the model are real-time, dynamic, multi-objective and multistage. The algorithm called ‘Harmonizing Cluster Results’ for the model is presented in order to solve the difficulties of solution for the workshop production system operation model. Then the model is simplified into some submodels, such as production ability optimization submodel, time optimization submodel, balancing and harmonizing submodel etc. Finally the operation optimization model and its solution algorithm are applied to an assembly line of energy meter in a factory. With the help of ‘Witness’ the application case simulation results showed that the model is accurate and its solution algorithm is reasonable and available.
Experimental Investigation on Air-Aided Water EDM
Authors: Yang Jun Jie , Zuo Zhi Jiang , Yu Wu Xin
Published: November 2010

Experiments for a new type of electric discharge machining (EDM) were conducted with the water film dielectric formed by tap water and compressed air. An energy factor E is introduced and employed to estimate unit-area effective power input. The experiments show that the flushing conditions with lower air jet pressure can get lower relative tool wear and higher material removal rate (MRR). Higher discharge current and higher energy factor E obtain the higher MRR in air-aided water EDM with positive polarity tool.
Loads Calculation of Pitch Bearing of Wind Turbine
Authors: Li Yun Feng
Published: November 2010

Loads calculation process for pitch bearing of wind turbine was presented. The aerodynamic of the rotor was analyzed by using momentum theory and blade element theory firstly; then the aerodynamic loads, the gravitational loads and the centrifugal loads of the pitch bearing were calculated along each axis of the bearing coordinate system; thirdly, all the loads of each direction of the pitch bearing load were composed into three loads, they are radial, axial and tilting moment loads. A calculation example was given at last.
Preparation and Selective Laser Sintering Mechanism of Polymer-Coated Mo Powder
Authors: Liu Bin , Bai Pei Kang , Li Yu Xin
Published: November 2010

A multi-component polymer-coated molybdenum powder was chosen for selective laser sintering (SLS). A novel preparing method of polymer-coated molybdenum powder was presented. The effect of the process parameters on the part’s characteristics is investigated. Based on our study for dynamic laser sintering process of polymer-coated molybdenum powder, its laser sintering mechanism was reported as follows: at the early stage of laser sintering, the viscous flow is the major mechanism; during the laser sintering, the melting/solidification is the major mechanism. Furthermore, a model corresponding to the mechanism was discussed schematically, which could be used to explain the material migrating mode during laser sintering process.
Combined Forecasting Model on Automotive Logistics Demand Based on RBF Neural Network
Authors: Gao Fei Fei , Fang Ji Chen , Zhang Qiang , Zhang Qin , Wang Zhan Gen , Shi Meng Zhu
Published: November 2010

This paper establishes a combination forecasting model based on Radia Basis Function Neural Network (RBFNN). It puts forward a seeking optimum parameters method by searching optimal solution for two-dimensional space (goal, spread) in a certain range, and realizes the combination forecasting of logistics demand, and improves the stability of network and the precision of prediction in RBFNN. An instance is presented to realize the model by MATLAB. The results showed that a good fitting precision and a high forecasting precision are reached in the application of the logistics demand forecasting by the designed forecasting model.
Semi-Analytic Solutions of Dynamic Response of Pavement Plate on the Elastic Foundation
Authors: Cao Cai Qin , Gao Chao , Huang Yi
Published: November 2010

The dynamic characteristics of the pavement plate on the elastic foundation were investigated. Based on semi-analytic element method and variational principle, the dynamic equations of the pavement plate on the elastic foundation were deduced. Through the analysis and calculation, dynamic response of pavement plate placed on the elastic foundation with vertical load was calculated by the semi-analytic element method. The deflection time histories curve of the plate under load on the elastic foundation was given. The effects of foundation parameters and the plate parameters are examined through numerical examples. The results show that the deflection of the pavement plate decrease with the increasing of thickness and elastic module of pavement plate, in the same time, the deflection of the plate is decreasing with the increase of the damping coefficient and elastic modules of foundation. Those parameters have significant effects on the deflection of the pavement plate.
Microstructure and Mechanical Properties of 6061 Aluminum Alloy Processed by Multi-Pass ECAE at Room Temperature
Authors: Dong Hong Bo , Wang Gao Chao
Published: November 2010

In order to investigate effect of equal channel angular extrusion (ECAE) on microstructure and mechanical properties of annealed and solution-aged 6061 aluminum alloys, continuous ECAE process was carried out by physical test and finite element methods. The results show that the grains are refined with the increase of deformation; the metal flow lines cross and shear each other to form the clear boundaries. The solution-aged Al alloy does not show a monotonic increase in surface hardness with increasing passes as the annealed Al alloy does, but reaches a maximum value after the second pass and decreases successively during next two passes, which is closely related with the dislocation multiplication, recombination and annihilation. For the annealed and solution-aged Al-6061, the peak load reaches a maximum value in the second pass and fluctuates during the additional passes, which is caused by both material properties and frictions. The simulation shows that the peak load increases slowly with increasing passes, which is not in agreement with the measured value. Therefore the finite element mode using a single constitutive equation is not suitable for simulating multi-pass ECAE processing. The constitutive relations need to amend accordingly due to great changes of the mechanical properties between different passes.
Continuous Modeling of Re-Entrant Manufacturing Systems
Authors: He Feng Lan , Dong Ming , Wu Zhi Gang
Published: November 2010

This paper presents a continuous modeling approach for multi-product re-entrant manufacturing systems. First, a generic continuous model for single-product re-entrant manufacturing systems is elaborated. Second, the concept of re-entrant factor is introduced to the model, which considers the influences of the re-entrant degree. Then, the continuous model is extended from single-product re-entrant manufacturing systems to multi-product re-entrant manufacturing systems in which the product priority is also taken into consideration. Finally, the proposed continuous model is validated through the Mini-Fab case study.
The Research on Thermal-Mechanical Coupling Simulation of Steam Turbine Vane Material’s Cutting Process
Authors: Yu Si Tu , Li Deng Wan , Xie Hong , Feng Jin Chun , Xu Ming Heng
Published: November 2010

In order to explore the cutting rules of the 43-inch vane material --1Cr12Ni3Mo2VNbN on the turbine vane, and research the stress in cutting area, the strain as well as the temperature distribution and the variation, providing the reference data for the large-scale vane-root milling cutter's geometric parameter design and the cutting parameter optimization, the authors employed ANSYS / LS-DYNA finite element method to simulate and research the cutting process of the vane material. The authors adopted the two-dimensional plane element 2D SOLID l62 of the single-point integration Lagrange algorithm to establish the finite element cutting model, and established the Cowper-Symonds constitutive models based on the vane material, applied the 2D-r adaptive meshing to simulate the separation of the chip and workpiece. Obtain the distribution and rules of the stress, the strain as well as the temperature in the cutting area, and greatly shorten the period of the vane root milling cutter’s designing and trial-production.
Laser Clad Geometry: Experimental Observation and Geometric Modeling
Authors: Wang Zhi Jian , Dong Shi Yun , Xu Bin Shi , Xia Wei
Published: November 2010

In this paper, a new analytical method of laser clad geometric simulation was developed. The effects of laser process parameters such as laser power, scanning speed, and powder feed rate on estimating clad geometry were investigated in this approach. A series of cladding was prepared by 1 kW diode pumping solid-state laser, to characterize the cross-section image of the clad by optical microscope. The clad profile was fitted by pitch arc and line in AutoCAD, with results displaying the arc-like upper profile of the clad. The theoretical results are discussed and compared with experimental data. The simulation based on the mass conservation is capable of predicting the clad width and depth with reasonable accuracy at medium powder feed rate.
Effects of Process Parameters on the Adhesion of Sputtering Protective Coating of Gd
Authors: Zheng Xiao Qiu , Xie Shi Kun , Yi Rong Xi
Published: November 2010

In order to research the adhesion of sputtering protective coating of Gd.Gd substrates were differently coated with Cu and Al by means of DC magnetron sputtering technology. The characteristics of the films were investigated by scanning electron microscopy (SEM), EDS, and the adhesions of films were tested by tension test. The results show that the films of Al are smooth and perfect, the interferences between Al and Gd join together strongly, and the largest strength of adhesion is 27.6MPa in these tests on the optimize parameters through orthogonal experimental design. While the films of Cu are rough and bad, the interferences between Cu and Gd join together loosely, and the largest strength of adhesion is only 3.02MPa in these tests on the optimize parameters through orthogonal experimental design.
Microstructures and Properties of the Al-4.5Zn-1.5Mg-0.5Mn Aluminum Alloy Welding Joints
Authors: Yang Shang Lei , Lin Qing Lin
Published: November 2010

The Al-4.5Zn-1.5Mg-0.5Mn aluminum alloy was welded by MIG welding in test, and the microstructure and mechanical property of joint were investigated. The results of experimentation show that the microstructure of welding metal is as-cast microstructure, and the microstructure of base metal is isometric crystal. There is a narrow fusion zone near the edge of weld seam, which consists of fine columnar grains. In the base metal and heat affected zone, the precipitation was diffuse in the intragranular, while strengthening phase η mainly focused on grain boundaries. The precipitation phases in the heat-affected zone distributed unevenly with large size, intermittent and segregation. In the welding metal, there is no precipitation phase. The microhardness on center of welding metal is lowest in joint. The tensile strength of welding joint is 272MPa, and the percentage elongation after fracture is 6.6%. The zone of fracture is located in the welding metal.