bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Aging Strengthening Behavior of ZK60 -2.0%Nd-1.0%Y Alloy
Authors: Wu An Ru , Dong Li Jun , Gao Wei Guo , Zhou Xiang Ling
Published: October 2010

The microstructure and mechanical properties of Mg-6.0%Zn-0.5%Zr (ZK60) and ZK60-2.0%Nd-1.0%Y alloys after extrusion, rolling and then T5 and T6 heat-treatment were investigated. The hardness and tensile strength at T5 and T6 condition were tested. The results show that the mechanical properties of ZK60--2.0%Nd-1.0%Y alloy are superior to that of ZK60 alloy. The hardness of the investigated alloy at T5 condition is higher than at T6. The strengthening of ZK60-2.0%Nd-1.0%Y alloy originates from the interaction of phase and dislocations. The precipitation order of ZK60-2.0%Nd-1.0%Y alloy is GP zone .
The magnesium alloy contains rare earth elements with good casting performance, great potential for plastic deformation, high strength, excellent mechanical properties and many other advantages. The magnesium alloy oversaturation solid solution's decomposition process conforms to time the common alloy oversaturation solid solution decomposition order rule, often namely before separating out the equilibrium phase presents some transitional stage the structure, like the GP area, the transition are equal, but the different series magnesium alloy presents the different characteristic, therefore uses the heat treatment method also has big difference [1-5]. In this paper, we will analysis mechanical properties of aging process of testing and microstructure of Mg-6.0% Zn-0.5% Zr-2.0% Nd-1.0% Y alloy , do Research about strengthen the effect of melting and from the product of the relationship on different alloy aging process, and analysis contribution of rare earth elements Nd, Y to alloy strengthen.
The Robust Design of Four-Bar Linkage with Clearance Based on Sensitivity Analysis
Authors: Yuan Ying Cai , Liu Yi Lun , Li Yan
Published: October 2010

Clearance is inevitable，so, with the increasing of machine’s speed, nonlinear vibration phenomenon caused by clearance is more apparent, which influences the precision and stability of mechanical system. For increasing the stability of mechanical system, a robust design method based on sensitivity analysis is studied, by using four-bar linkage as the research object, deducing the nonlinear dynamic model with clearance and the sensitivity of dynamic response, based on the rational planning to the tracks and control the sensitivities. In the design example, it shows that although the track deviation of robust design is slightly bigger than that of optimization design, the comprehensive dynamic performance of the mechanical system is much better than the latter, which means the stability of mechanical system is improved greatly. Thus, the robust design based on sensitivity analysis is an effective way to improve the stability of the mechanical system.
Application of Ground Penetrating Radar to Rock Failure Analysis in High Risk Tunnels
Authors: Zhang Le Wen , Sun Huai Feng , Li Shu Cai , Qiu Dao Hong , Zhang De Yong
Published: October 2010

The authors found a type of sidewall failure during the construction of a tunnel with high geostress. And relative strong rockburst usually occurred in the areas nearby during the excavation. This paper shows this type of failure called Crisp Fissure Failure and some characteristics of the failure. Reasons of the failure are also discussed. Further more, the authors studied the fracture distribution under this type of failure by Ground Penetrating Radar. Suggestions of support in a high risk tunnel are put forward based on the research of the Crisp Fissure Failure.
On High Pressure Squeeze Pack Numerical Simulation of Unconsolidated Sandstone Based on Discrete Element
Authors: Wang Wei Zhang , Yan Xiang Zhen
Published: October 2010

Sand inflow is one of the problems in unconsolidated sandstone oil reservoir recovery. The most frequently applied sandcontrol method is high-pressure gravel squeeze packing sand control technology. But incorrect knowledge of stratum shapes under high-pressure squeeze packing leads to unreasonable technology and implement parameters. This thesis, based on the discrete element theory and by means of two-dimension grain flow simulation software PFC2D, considers three oil wells with unconsolidated sandstone in terms of their cementing strengths . The simulation result shows that strata with diverse cementing strengths vary remarkably when high-pressure squeeze pack is asserted. Established calculation pattern might lead to sizable deviation.
Performances of the Hybrid Active Desiccant Wheel System with Type III Desiccant
Authors: Zuo Yuan Zhi , Wen Sheng Li , Li Xi Ya
Published: October 2010

A new type of hybrid desiccant air conditioning system combining an active desiccant wheel with a conventional front-positioned cooling coil is presented, in which Type Ⅲ desiccant is used in the active desiccant wheel. Then a preliminary experiment is carried out in order to investigate the feasibility of the hybrid desiccant system serving as a dedicated outdoor air system (DOAS). The result shows: under the two typical outdoor air conditions in the area of South China, the desiccant system which only needs to adopt a regeneration temperature of 45°C without lowering the cooling coil temperature can satisfy the requirements of the dehumidification; when operating in the climate with a high humidity of 90% and a high-temperature of no more than 36.5°C, the desiccant system only driven at a regeneration temperature of 60°C can also provide enough dehumidifying capacity; but compared with the active desiccant wheel using Type Ⅰor Type Ⅱ desiccant, this system can not reach a lower dew point. Therefore, this system can operate effectively at a moderate regeneration temperature, suitable for the high quality and comfortable air conditioning.
Research on Fracturing Mechanism of Ground-Drive Screw Pump Polish Rod
Authors: Wang Wei Zhang , Wang Hai Wen
Published: October 2010

In addition to vertical pulling force, the ground-drive screw pump oil recovery rod also stands twisting moment and bending moment. The diameter of the polish rod is generally larger than that of the pumping rod, and it stands a bit less stress than the pumping rod close to it, and the polish rod is generally made of relatively better materials. In practice, however, the polish rod fractures more often than the pumping rod above. This thesis considers that if the driving head deflects, the upper and the lower polish rods of the packing set are not in the same axial line, and bending moment will come into being in the polish rod of the lower part of the packing set due to the restriction of the polish rod by the packing set. Alternating stress caused by bending moment yields fatigue rupture of the polish rod during its rotation. This verdict is confirmed by the fracture position, the shape of the fractured surface, and quantitative calculation. This thesis proposes strict controlling of the deflection of the driving head by means of polish rod verticality survey instrument. Both theory and practice have proved that this method can effectively avoid fatigue rupture of the polish rod.
Experimental Research on the Thermal Insulation and Flame Retardancy Performance of WPC Wallboard Made of Paper-Aluminum-Plastics Wastes
Authors: Gao Song , Li Qiu Yi , Zhang Yi Wen
Published: October 2010

As a high technique environmental friendly material, Wood-plastic composite (WPC) material has wide range of applications and is extruded by recycled wood fiber products and wasted LDPE. Waste Paper-Al-Plastic materials including Tetrapak beverage and milk boxes are used to extrude the WPC as thermal insulation exterior wallboard instead of normal wood fiber material in the present research. In this paper, simulated thermal insulation and Oxygen index combustion test were operated at the Lab conditions. Some experimental results are presented as follow: heat transfer coefficient of 100mm thick WPC hollow wall is 0.922 W/m2•K, which is equivalent to the thermal insulation performance of a 0.35m thick fly ash aerated concrete block. Oxygen index of 27 indicates that WPC is inflammable material. Zinc borate (ZB) and ammonium polyphosphate (APP) are effective flame retardant for Paper-Al-Plastic WPC.
ICAN Series Functional Module Theory in Lifting Moment Restriction System
Authors: Huang Ju Sheng , Tu Li , Liu Jun An , Tan Li Xin , Qu Xi Long
Published: October 2010

Taking construction crane for example, this thesis builds a reliable, controllable and easy-to-exploiting CAN-bus application network on the basis of iCAN series functional module and CAN-bus interface card of ZLG system, and it explores the methods of rapid allocation in control networks of construction engine. With CAN-bus controlling devices to guide all signals of sensors and output dates, this system is easily constructing and conveniently stalling. Meanwhile, this system has a good anti-inference ability, a high reliability and a good real-time response. The application of CAN-bus enables lifting moment restriction system to act as a subsystem embedded in other engineering control systems. The construction of this system has an important reference in explore a new generation of engineering control system.
Effects and Mechanism of Titanium Modification on Shrinkage Cavity and Porosity of Cast Steel
Authors: Wang Hai Tao , Yu Hua Shun , Xu Hui Zhong
Published: October 2010

The effects of titanium modification, which was added along with the pouring liquid in ladles, on the shrinkage porosity and cavity of cast steel ZG35 smelted in intermediate frequency induction furnace were studied. Proper content of titanium could effectively increase the volume of concentrated shrinkage cavity, and restrain the forming of shrinkage porosity. The concentrated shrinkage cavity was analyzed quantitatively by stuffing wet gluten and draining water method. The maximal cavity arrived at 0.15wt.% titanium modification. By scanning electron microscope (SEM) and energy disperse spectroscope (EDS) analysis, it was found that TiC, acting as heterogeneous nuclei, could refine the structure grains, diminish the strong dendrites, and increase the fluidity and feeding capacity of steel liquid. However, overdoes titanium modification easily caused mass nitrides or oxides, which kept solid phases with high meting point in metal liquid to increase its viscosity and decrease the fluidity. On the other hand, these solid state titanium compounds enlarged the composition supercooling, so the metal liquid changed from sequential solidification to simultaneous solidification, resulting in inadequate metal liquid feeding, less oncentrated shrinkage cavity and serious shrinkage porosity.
Load Analysis of Crankshaft of Axial Three-Cylinder Hydraulic Confined Piston Engine
Authors: Zhang Hong Xin , Zhang Tie Zhu , Zhao Qin Hai
Published: October 2010

Hydraulic confined piston engine (HCPE) is a new type power device which can directly turn indicated work into hydraulic power, and three cylinders axial HCPE prototype has been manufactured. The load and stress study on its crankshaft is very important for future design. The working principles of HCPE was discussed, the mathematic model of its working process was constructed, and the load on crankpin by connecting rod was obtained by simulation. The total contact model of crankshaft reflecting the actual conditions was built, through which Von Mises stress, contact stress and friction stress of crankshaft were calculated. The maximum of Von Mises stress occures at the fillets of main shaft neck. The fatigue secure coefficient of crankshaft is about 2.85, which meets the demand.
Dynamic Analysis for the Wind Turbine Generator Blades
Authors: Sun Wen Lei , Chen Hai Ping , Wu An
Published: October 2010

This paper carried out the effective dynamic simulation analysis for the 750KW Horizontal Axis Wind Turbine blades in the wind, gravity and centrifugal force coupling. Based on the selected turbulence model, and considering the natural flow of air as a viscous incompressible steady flow, and the fan blades as the flexible body, simulated the flowing line graph of wind wheel surface, and the overall mechanical performance data at any moment. After effective analysis of the Coupling force, obtained the deformation distribution patterns and rules, which provide much reference to the further failure analysis of fan blade and structural optimization design.
The Dynamic Research on Flexible Impeller of the Large Wind Generators
Authors: Sun Wen Lei , Dang Chang Ying , He Lian Ying
Published: October 2010

According to designed parameters, the rigid model of the large wind generators has been built in UG software, the impeller is selected to be researched object, modal neutral files of key parts are attained by the analysis in ANSYS software. The analysis model of multi-flexible bodies of the impeller is built in ADAMS software. With analyzing, predigesting, loading of wind loads and analyzing of dynamic simulation of impeller model, a lot of dynamic parameters of flexible impeller are obtained, which are truer and exacter. These provide certain basis of the loads for designing, analyzing, optimizing the design of key parts of large wind generators in future. The new thought is explored, which are about dynamic research of multi-flexible bodies of large wind Generators. Further more; the high-performance large wind generators are designed.
Comparative Study of Drill Pipe Erosion Wear in Gas Drilling and Mud Drilling
Authors: Zhu Xiao Hua , Liu Shao Hu , Tong Hua
Published: October 2010

Failure of drill pipe is very severe in gas drilling. Based on the erosion theory and field condition, the erosion of drill pipe is investigated by using numerical simulation. The agreement between the simulation result and experimental data is very good, this agreement indicates that the numerical model is realistic in this paper. The erosion wear of drill pipe is investigated in gas drilling and mud drilling by using this model. According to study result of drill pipe erosion between gas drilling and mud drilling, the erosion rate of drill pipe in gas drilling is greater than that of in mud drilling. The result shows that the local erosion rate of joint is more severe than that of the drill pipe body in gas drilling, and also the local erosion of drill pipe body is severe. There are many eroded pits on drill pipe body in gas drilling. This study will reveal the failure mechanism of drill pipe in gas drilling, and also have some guiding significance to reduce the failure of drill pipe.
Analysis of Flow Field on Hydraulic Unit of the Water Injection Pump by 3-D Numerical Simulation
Authors: Tong Hua , Zhu Xiao Hua , Deng Fu Cheng , Liu Shao Hu
Published: October 2010

In order to clarify the abnormal failure mechanism for the spring of the water injection pump, the velocity and the pressure are simulated for hydraulic unit in different driven angle. The eccentric load is found in the ansys, which is the main factor for leading to the exceptional failure of the spring. The improvement method is presented by using Computational Fluid Dynamics (CFD) technology. Flow field of the improved hydraulic unit is more uniform after the numerical simulation. The effect of eccentric load is greatly reduced for the suction spring. At the same time without changing the rate of flow, section surface of the suction valve and the discharge valve is appropriately reduced to bring down the load of the spring. The fluid dynamics analysis and optimization of the hydraulic unit has been completed in this paper. This study has great significance in perfecting the working theory of the water injection pump and raising the robustness of the pump’s motion.
Optimal Design of Slip Dog Based on the Elasticoplasticity Contact Analysis
Authors: Zhu Xiao Hua , Wang Yu , Deng Fu Cheng , Tang Li Ping , Tong Hua
Published: October 2010

Based on the elasticoplasticity contact analysis theory, a mechanical model for the whole process of the slip holding fast to the drilling pipe is established and a complete method is proposed to assess the performance of slip dog's structural parameters. For drilling pipe systems of different specifications, the coupling effect among tooth anterior corner, posterior corner, tooth height, tooth spacing of slip dog and the effect of the parameter variation on both the drilling pipe and itself after the slips hold fast to the drilling pipe are analyzed, and the slip dog's plastic damage law on the drilling pipe under different parameter combinations is obtained. Using this law to instruct field slip dog design, it is discovered that this slip dog significantly reduces the drilling pipe's plastic damage by both laboratory and field experiments, which has proved the universality and applicability of this method, effectively reduced the drilling operational risk and drilling costs. The technology has been put into use in Sichuan and Chongqing region and acquired good technical assessment.
Surface Analysis of Electrical Arc Residues in Fire Investigation
Authors: Wu Ying , Gao Wei , Di Man , Zhao Chang Zhang
Published: October 2010

At most fire scenes, electric short circuit (ESC) arc beads that may be provide useful information on the cause and development of the fire are found. Various physical or chemical methods have been proposed for identifying these electric short circuit beads to be either the cause of a fire (primary arc beads) or one caused by the flames of the fire (secondary arc beads). Little was studied, however, on their identification using the cupreous oxides formed in the molten marks. In this study, the concentration of metallic Cu and Cu2O in the surface region and subsurface was quantified by X-ray photoelectron spectroscopy (XPS). As a result, it can be examined to distinguish the primary and secondary arc beads by comparing the distribution of the substances of Cu and Cu2O.
Fatigue Propagation Lifetime Prediction of Rotary Kiln Weld Shell
Authors: Shen Y.P. , Bin G.F. , Wang S.L.
Published: October 2010

Rotary kin shell is welded by cylindrical steel plates. Crack propagation of weld toes near supporting rollers until final fracture is the main failure form. Based on fracture mechanics, an overall intensity factor with regard to circumferential stress, concentrated stress, residual stress, and temperature stress is used to asses the crack growth. Under complex overloading conditions, the major factor, namely, circumferential stress across shell, is calculated by using finite element (FE) code ANSYS. Concentrated stress, residual stress, and temperature stress play a major role in the fatigue growth behavior, thus their effects are considered in a theoretical analysis to be included in the overall intensity factor. A certain extent good lifetime results are obtained compared with practical observation. This paper presents a reasonable procedure to evaluate propagation lifetime of weld shell, and the results are quit significant for equipment daily maintenance of rotary kiln.
Design Theory of Profile Connection and Overview of Manufacturing Technology
Authors: Zheng You Yi , Rao Ji Lai , Wu Lei
Published: October 2010

This paper mainly introduces the concepts and brief development history of profile connection, brief discusses its design theory and manufacturing techniques and finally some application prospect are put forward.
Design of an Images Security System
Authors: Huang Feng , Liu Xing Ping
Published: October 2010

The paper designs an image security system. It includes four parts: keys generation, permutation, diffusion and decryption. Using six decimal numbers as the key, it can get three new keys: key1, key2 and key3 from the origin key in keys generation. The permutation used a new chaotic map to shuffles the image pixels by key1 and key2. The diffusion used the logistic map to flat the histogram of the ciphered image. The key3 is the parameters of the logistic map. The results of simulation show the validity of security system. Analysis shows that it can be used in real-time image encryption applications with high speed.
Design of Multi-Channel Data Acquisition System Based on PXI 6281
Authors: Huang Feng , Zhao Jian Kai
Published: October 2010

The paper designed a multi-channel data acquisition system based on PXI 6281. It used DAQmx technology in LabVIEW for synchronous analog channel data acquisition. It realized multi-channel real-time data acquisition, processing, display and data auto-saving. Data acquisition system consists of three major modules: the pressure measurement module, the motor speed measurement modules and real-time temperature measurement module. It has advantage of short cycle of technological upgrading, development and low maintenance costs. It has some reference value for other data acquisitions.
Research on Education of Creativity and Innovation
Authors: Lei Fang Fang
Published: October 2010

The paper proposed a training mode for undergraduates of creativity and innovation in engineering education. It includes three elements: Precise and professional personnel training, application-oriented teaching mode and strict quality supervision. Only trinity, it can train good engineering talent. The paper proposed a practical method. It is proved by the practice of engineering education in years.
Tool Wear Monitoring in Milling Processes Based on Cointegration Modeling
Authors: Cui Yin Hu , Wang Guo Feng , Peng Dong Biao
Published: October 2010

Tool wear monitoring plays an important role in the automatic machining processes. Therefore, a reliable method is necessary for practical application. In this paper, a new method based on cointegration theory was introduced to extract features from the cutting force signal in the milling process. Cointegration relationship between cutting forces of different directions could be found and the corresponding cointegration vector could also be calculated. In order to improve the reliability of pattern recognition, the cointegration vectors combined with the energy of the high-frequency components of the acoustic emission signals were used as features. Once all the features are extracted, they were trained and tested through a support vector machine model. Experiments were performed to verify this method and the results showed that it could efficiently recognize the tool wear status.
Bifurcation Control for a Kind of Non-Autonomous System with Time Delay
Authors: Qian Chang Zhao , Wang Zhi Wen , Dong Chuang Wen , Liu Yang
Published: October 2010

A forced van der Pol system with two time-delays is studied. The central aim is analyzing primary resonance of this system. Perturbation method is used to obtain the average equation and bifurcation equation with time-delays. Based on the average equation, the stable region of this system is discussed. Based on the bifurcation equation, the multivalued property of response amplitude is studied. The result indicates that this system can be well controlled with time delays.
Research on Dynamic Characteristics of 750KW Wind Turbine Flexible Blades
Authors: Wang Yi Ping , Sun Wen Lei , Zhao Qun
Published: October 2010

It is necessary and fitting to use flexible multibody dynamics method to study the wind turbine blades. Because the characteristics of the blades will directly affect the whole wind turbine’s, and the results by using flexible multibody method are to agree with reality. Considering the anisotropic composite blades, it established the flexible blades model and rigid-flexible wind rotor model of the 750KW wind turbine by the software of ANSYS and ADAMS. Then fit the loads which are computed from BLADE to the wind rotor, analyze the dynamic characteristics of the rotor. It gets the dynamic features of the flexible blades and the rigid blades’ as a comparison, which will be useful to research on WTGS, and will supply reference data to blade trouble analysis and optimization design.
The Numerical Simulation of Aerodynamic Performance for Wind Turbines’ Blade Wheel
Authors: Dai Dan Dan , Sun Wen Lei , Zhao Qun
Published: October 2010

It’s necessary to research on the interaction of blade wheel with incoming flow. The CFD method was used in this paper for numerical simulation of the aerodynamic performance for wind turbines’ blade wheel at rated wind speed. The first thing was the establishment of wind turbine dynamic model of blade wheel. Then using Fluent software to simulate the three-dimensional flow field around it. The visual images on pressure distribution，flow rate distribution and velocity vector of the blade were obtained. Also, the load and the torque of the blade were calculated. The reliability of this numerical simulation is inspected in this paper. Some technical parameters and instructional suggestions about how to design the blade as well are proposed.
Cotton Picker Picks Roller Motion Simulation and Dynamics Analysis
Authors: Sun Wen Lei , Li Xiao Li , Fu Chang Bing
Published: October 2010

The drum is the process of picking cotton, picking cotton picker cotton picker head of the key device, which controls the seat tube and Abstract Abstract ingot of movement, Abstract spindle picking of cotton is also directly affect the quality and efficiency of key factors. Therefore, by creating a virtual prototype model cotton picker roller, about picking cotton picker principle, and the movement simulation model to arrive at, dynamic model of the external force, the cotton picker spindles moving speed of the Summary Block pipe displacement, velocity and acceleration effects. Then summed up, cotton picker of road speed, picking rate and the net rate of mining.
Research on a Kind of New Green Precision and Micro-Manufacturing Technology
Authors: Bao Huai Qian , Wang Chang Tian , Han Bao Kun
Published: October 2010

In order to develop the green manufacturing and microfabrication, an innovative micro-electrochemical machining (ECM) method¬¬-the electrochemical machining in pure water was studied. On the base of experimentation principle, ECM set up was developed for engineering application. Water dissociation mechanism is found under the function of cation exchange membrane, and many factors to enhance current density were analyzed. As a result of technological test, a micro hole is machined in the thin stainless. It is confirmed that electrochemical machining technology is feasibility to make use of pure water as electrolyte.
Algorithm Research for Non-Preemptive Scheduling on Multiprocessor
Authors: Liu Tie Wu , Bai Lin Feng , Zhang Tie Nan , Qu Xi Long
Published: October 2010

Research for algorithm of non-preemptive scheduling on multiprocessor is of great theoretical significance and practical significance. Based on non-preemptive scheduling, the performance of the algorithm is analyzed and investigated on two different objective functions about the turnaround time of the system and the low-cost problem with a limitation of time. Finally, the relevant conclusion is obtained which is the basis of the further research. It gives a guarantee to the algorithm performance which is designed for the practical application.
Study on Additional Electrical Current on Machinability of Free-Machining Steels in Turning
Authors: Lin Yong Chuan , Chen Yuan Ling
Published: October 2010

This paper deals with the mach inability of BN free-machining steel in turning with a supplied current of various values and different directions of electrical current. The tested work pieces were, standard steel AISI 1045 and BN added steel (AISI 1045-BN) based AISI 1045 which has good mach inability at high cutting speed. Turning tests were performed by carbide tool P30 and the power source for additional electrical current supply was a direct current source and the maximum electrical current in the circuit was 20milliamperes (mA). To investigate the influence of electrical conditions of closed circuit system on the cutting mechanism of AISI 1045-BN. The tool life, cutting force, and others were determined experimentally. The testing results show that when turning with carbide tool P30 the maximum crater depth in the tool was reduced drastically when the value of supplied current reached 5mA, regardless of its direction of flow, compared with depths at lower current values; the additional electrical current cutting showed smaller cutting force than those of conditions when turning AISI 1045-BN.
Effects of Cr Doping on the Structural and Electrochemical Properties of V6O13
Authors: Liu Yuan Chun , Zou Zheng Guang , Long Fei
Published: October 2010

It has been demonstrated that V6O13 is a very attractive cathode materials for rechargeable lithium-ion batteries. Cr3+ was doped to improve its electrochemical property. CrxV6O13(x =0.01~0.05) cathode materials were prepared using NH4VO3 and Cr2O3 as raw material by solid phase method in argon atmosphere. The best electrochemical properties of CrxV6O13 were obtained under the optimum conditions as follows: the argon flow rate is 85mL/min, the heating rate is 5°C /min, the holding time 1h at 180°C, 1h at 300°C and 30 min at 450°C. The structural and electrochemical properties were examined by means of X-ray diffraction, SEM and charge–discharge tests. The results demonstrated that the powders maintain double cavity chain structure regardless of the chromium doping. When the Cr doping of x = 0.03, capacity is highest. Maximum initial discharge capacity is 334mA•h/g, 80% of theoretical capacity. During discharge process there is 6.5 Li+ embedded in the Molecules of doping. After discharge cathode became Li6.5Cr0.03V6O13.
Preparation of Graphene with Ultrasound-Assisted in the Process of Oxidation
Authors: Yu Hui Jiang , Zou Zheng Guang , Long Fei , Xie Chun Yan , Ma Hao
Published: October 2010

To get single-layer of graphene, exfoliating fully intercalated graphite oxide into single- layer graphene oxide is one of the important factors. In this paper, graphite oxide prepared by the Improved Hummers Method, and ultrasound was added to the Low-temperature Reaction of this oxidation process to improve the efficiency of intercalation. Then the obtained graphene oxide was dispersed with surfactant and reduced with Hydrazine Hydrate. XRD patterns indicated that the layer distance of graphite oxide did increased at the aid of the ultrasound, and the obtained reduced products were single- and few-layer. FT-IR analysis further confirmed the preparation of graphite oxide and graphene.
BDA Models and Application for Recognizing the Headstreams of Mine Waterburst
Authors: Wan W. , Jie L.
Published: October 2010

BAYES discriminant analysis (BDA) method was used in the study of headstreams of prediction of minewater inrush and two BDA models for recognizing two-headstreams and multi-headstreams were constructed. Baesd on the principle of BDA theory and the classical headstream samples of different mines, the discriminant process and cross-validation method were introduced. 10 samples from a mine of HUA BEI Mine and 39 samples of JIAO ZUO Mine were used as data sources. Ca2+, Mg2+, Na+, K+, Cl-, HCO3-, SO42-, NO32-, F- and pH were selected as discriminant genes for two-headstreams BDA model and Na++K+, Ca2+, Mg2+, Cl-, SO42-, HCO3- were regarded as discriminant genes for multi-headstreams BDA model. Compared with the results of SQT method, ANN method and SVM method, the results show that the frame of BDA model was steady and high prediction accuracy can be obtained. BDA method and can be used in practical mine engineering.
The Performance Validation of Linear Programming Algorithm Based on Integrated Benchmark
Authors: Chen Shu Hong , Yan Guo Feng
Published: October 2010

Benchmark is a method of measuring performance, and we can obtain continuous performance improvement of programming algorithm through Benchmark validation. In order to solve large-scale linear programming problems, this paper proposes an integrated Benchmark validation which integrates theoretical Benchmark analysis with advance language-based Benchmark. Through the integrated Benchmark validation, we can continuously improve an optimizing algorithm, and validate whether the new optimizing algorithm achieves the performance objectives. The results of experiments show the proposed integrated Benchmark validation is an effective method for developing large-scale linear programming algorithms.
Finite Element Analysis of Vertical Continuous Collapse of Six-Story Frame Structure
Authors: Zhang Yu Min , Sun Cui Juan , Su You Po , Su Jing Yu
Published: October 2010

The capability of structure resisting progressive collapse depends on controlling the dispersion of damage by uncommon agency in the part of the structure and to avoid the destruction just likes the Domino action. For the RC frame, when one column under the beams was broken, the key to avoid progressive collapse is whether the frame beams can bear the column’s load to produce a new way for transmitting the force or not. In this paper, the simulation analysis to a six-layer frame structure which designed by the concrete structural design codes is put up according to the four failure position of columns. The following conclusions are concluded: the damage in vertical region does not appear or appear very little because of a strong stiffness in joint between invalid column and beam. Structural collapse was resulted by the collapse stress from displacement transfering the other end of beam connected with columns.
Corrosive Wear Behavior of Several Materials Coupled with Si3N4 in the Molten Zinc
Authors: Ma Rui Na , Du An , Wu Jian Jun , Cao Xiao Ming
Published: October 2010

In continuous hot dip galvanizing, serving parts working in the molten zinc, such as sink roll, sleeves, etc. tend towards degradation and failure due to corrosion and wear. In this paper, corrosive wear performance of several materials, such as boronized，H13，Co-based alloy and Fe-based alloy coupled with Si3N4 is evaluated with the aid of a self-made test machine of block-column sliding wear. Moreover, the corrosive wear mechanism is analyzed. It has been found that these materials suffered not only considerable wear, but also the corrosion of molten zinc. For boronized layer, the wear is the main reason to cause the failure of work parts under the act of the corrosive wear. For H13, the interaction between corrosion and wear plays a very important role on its failure. For those alloys with bad corrosion resistance such as Co-based alloy and Fe-based alloy, both corrosion of solid solution and wear of intermetallic compound act on their failure at the same time. However, the rate of wear shows no obvious relation to the hardness although wear performance is important. The failure greatly lies on the ratio of the hardness of corrosion products to matrix.
An Experimental Study on Oil-Air Lubrication of Sliding Friction Element
Authors: Cai Lin , Wang Jin Li , Zheng Hong Tao
Published: October 2010

The objective of this research is to study the lubricating property of oil-air lubrication on sliding friction element. The performance of sliding friction element under different lubrication parameters and preloads were investigated by measuring the element’s temperature and friction coefficient. The results show that oil air lubrication could complete the lubrication and cooling of sliding friction element. As the oil supply is increased at the same load, speed and air supply level, the temperature rise and friction coefficient decrease, but when the oil supply is increased to 15ml/h, they remain unchanged. As the air supply is increased at the same load, speed and oil supply level, the temperature rise decreases monotonically and the friction coefficient remains steady.
On-Line Measuring Principle of Ferrous Ion in Fluxing
Authors: Du An , Ma Rui Na , Fan Yong Zhe , Cao Xiao Ming , Li Shi Jie , Zhao Shu Peng
Published: October 2010

A spectral absorption of the ferrous ion in fluxing was investigated in this paper due to the significant effect of ferrous ion on the quality of hot-dip galvanizing production. Based on analysis of spectrophotometry, an automatic detection equipment of ferrous ions is developed according to its special characteristics. On-line measuring of ferrous ion in fluxing of the hot-dip galvanizing is realized by the micro-pump and the equipment. Results show that the lowest limit to be detected is 0.1 g/L, measuring errors are less than 0.05 g/L, the linear equations of the absorption and concentration of the ferrous ions shows a good correlation coefficient which is 0.99995 when the ferrous ions concentration is between 0.1g/L and 10g/L in fluxing.
Effect of Cryogenic Minimum Quantity Lubrication (CMQL) on Cutting Temperature and Tool Wear in High-Speed End Milling of Titanium Alloys
Authors: Su Yu , He Ning , Li Liang
Published: October 2010

Cryogenic minimum quantity lubrication (CMQL) is a kind of green cooling/lubrication technique, which consists of the application of a small amount of lubricant (6-100 ml/h), delivered in a refrigerated compressed gas stream to the cutting zone. This paper experimentally investigates the effect of CMQL on cutting temperature and tool wear in high-speed end milling of titanium alloys. Comparative experiments were conducted under different cooling/lubrication conditions, i.e. dry milling, refrigerated air cutting, and CMQL. The refrigerated gas equipment was manufactured based on composite refrigeration method to provide the refrigerated air. The experimental results show that application of CMQL resulted in drastic reduction in cutting temperature and tool wear especially when machining titanium alloys at a high cutting speed.
Cognates and Spherical Hinge Replacement of Spatial RSSR Mechanism
Authors: Lu Ning Zhou , Zhang Zheng Yan , Chen Ding Fang
Published: October 2010

This paper resolves spatial RSSR mechanism in D-H coordinates to obtain its position equations. By extending Roberts-Chebyschev Theorem, it is demonstrated mathematically that RSSR mechanism possesses the same character as planer four-bar linkages in generating cognates. Considering strict requirements of spherical hinges in manufacture and assembly, this paper then addresses substitution methods of spherical hinge in RSSR mechanism, including constraining DOF of spherical pair by specific structural dimensions and replacing high pair by combinations of low pairs, while taking examples of sphere 4R mechanism, spatial orthogonal crank-rocker mechanism and spatial 6R mechanism in dobby machine. Physical kinematic simulation is done in the environment of MSC.ADAMS to validate the feasibility of spherical hinge replacement, providing guidance and reference to future design of complex spatial mechanisms.
Study on Turning Parameter Optimization of Austenitic Stainless Steel
Authors: Li Deng Wan , Chen Hong Tao , Xu Ming Heng , Zhong Cheng Ming
Published: October 2010

In order to explore the cutting rule of hard-to-machine material austenitic stainless steel and to optimize cutting parameters, multiple sets of parameters of austenitic stainless steel cutting were schemed out by using uniform design method. Test cutting researches of cutting forces, surface roughness and cutting efficiency with these parameters were conducted under the condition of dry cutting. On this basis, multi-objective optimization model of cutting force and surface roughness applied to austenitic stainless steel had been set up by multiple regression analysis. Variance analysis showed that these formulas have highly significant linear relationship. Verification test is done under the optimal cutting parameters, and the results of cutting forces and surface roughness are in good agreement with the calculated. Turning efficiency is improved by 23.4%, compared with the actual cutting parameters of past production.
Optimal Design of Engine Variable Stretching for Valve Stem of 157FMI
Authors: He Chang De , Yang Pu Xin
Published: October 2010

When designing motorcycle engine, engine cylinder head abnormal noise is common, and difficult to eliminate due to thermal expansion and contraction of the aluminum alloy cylinder head. In this study, on the basis of dynamic change with the performance of 157FMI engine in hot and cold, the reasons for engine cylinder head abnormal noise are analysed, and valve plunger with variable length is applied to minimize the valve clearance, and to make the valve clearance of engine in cold and hot zero, and thus the noise problem of cylinder head with 157FMI engine in hot is completely eliminated.
Finite Element Modal Analysis of the Quick Positioning System of Wire Bonders
Authors: Bai Quan , Wei Ke Xiang , Zhu Shi Sha
Published: October 2010

The positioning system with high acceleration and high precision determines the speed and quality of bonding, which is the core component in a wire bonder, and influences the cost and reliability of the chip. The mode characteristics of the high acceleration and high precision positioning system were analyzed using ABAQUS. The results show that the system has different vibration characteristics in different resonance mode, and also has the features of mode denseness and complicated vibration mode.
Study on the Mechanical Performance of Glass Fiber 2D Woven Fabric Laminated Composites with Different Splicing Shape and Interval Length
Authors: Zhang Guo Li , Wang Fu You , Li Jia Lu , Chen Guang Wei , Chen Li
Published: October 2010

In order to investigate the effect of splicing shape and splicing interval length of reinforced fabric on the mechanical performance for manufacturing composite parts in complicated shape with laminated 2D glass fiber woven fabric. On the basis of [0º/45º/90º/90º/0º] S ply sequence, six kinds of laminated performs with different splicing interval lengths which were 4mm, 8mm, 12mm respectively and two different splicing shape which were ladder splicing (LS) and double vertical line splicing (DLS), and a kind of laminated perform with continuous laminates (CL) of 2D glass fiber woven fabric were made. By means of RTM molding technology, the technological parameters of RTM processing were designed as follows: injection temperature was 25°C, injection duration time was 180min and injection pressure was 0.4MPa, the epoxy resin based 2D glass fiber woven fabric RTM laminated specimen were prepared. According to the GB/T 1447-2005 and GB/T 1449-2005standard test method, the tensile and flexural properties of the 2D glass fiber woven fabric laminated RTM specimen were tested. It was found that the tensile fracture position were all near the splicing line, the main reason of which was the concentration of tensile stress. The tensile and flexural test results show that the difference of the splicing shape and the splicing interval length will generate a significant effect on the mechanical performance of the laminate. All above experimental results could provide fundamental data to the optimal design complex structure laminated composite parts.
Dynamic Characteristics of Vibrating Screen with Determinate Structure and Statically Indeterminate Structure
Authors: Yan Jun Xia , Liu Chu Sheng , Zhao La La
Published: October 2010

Analyzed vibrating screen’s dynamic characteristics of determinate structure and statically indeterminate structure, calculate natural frequency, natural vibration mode and dynamic response based on finite element technology. The results show that the vibrating screen’s structural strength is increased and the natural frequency of bending and twisting deformation is improved by means of the adoption of statically indeterminate structure. The natural frequency is far from work frequency which means the structure can avoid resonance effectively. Statically indeterminate structure provides a big structure intensity and stiffness to meet vibrating screen’s needs in the design process.
Study on the Tensile Strength Loss Rate of Glass Fiber 2D Woven Fabric Reinforced Laminates with Ladder Splicing
Authors: Wang Fu You , Zhang Guo Li , Chen Li , Chen Guang Wei , Zhou Qiang
Published: October 2010

This research paper presents an experimental investigation on the tensile strength loss rate of glass fiber reinforced 2D woven fabric with ladder splicing laminate composites. On the basis of three kinds of ply sequence, two series of laminates with different plies numbers were prepared through RTM molding technology, including ladder splicing(LS) laminates and continuous laminates (CL). And the RTM technological parameters of RTM processing were designed as follows: injection temperature was room temperature, injection duration time was 180min and injection pressure was 0.5MPa, the epoxy resin based 2D glass fiber woven fabric RTM laminated specimen were prepared. According to the GB/T 1447-2005 standard test method, the tensile tests of the 2D glass fiber woven fabric laminates were carried out. Results show that the tensile strength loss rate of ladder splicing laminates is 11.05%, 9.37%, 7.78% while the number of plies is 8, 10, 12 respectively. In other words, the tensile strength loss rate is reduced with the plies number increasing. In addition, because of the concentration of tensile stress, all fractures of ladder splicing laminates occur at the site of splicing line.
Modeling and Simulation on Light Axial Piston Pump
Authors: Ding Wen Si , Wu Hui Yan
Published: October 2010

Flow and pressure regulation axial piston pump is studied in this paper. Model of the pump is built in AMESIm, and then characteristics of flow rate and pressure are calculated and analyzed in this model. This provides a good platform to the design and research of axial piston pump.
An Approach for Construction of Fault Trees Using Rough Set and Fuzzy Clustering Algorithm
Authors: Tu Ju Liang , Duan Rong Xing , Dong De Cun
Published: October 2010

This paper presents a novel methodology for the construction of fault tree using rough set and clustering algorithm. Taking advantage of the strong ability of RS theory in processing large data and eliminating redundant information, this method can remove irrelevant factors from the original fault data and reduce the dimension of processing data which helps to overcome fuzzy clustering algorithm's defect when process large database. The method is introduced and explained in details and its correctness and completeness is validated by Fault tree construction of oil-immersed traction transformers.
Knowledge Representation Method of Product Principle Solution Based on Semantic Network Model
Authors: Chen Xiao Ying , He Bin
Published: October 2010

Product design is a problem-solving activity based on knowledge. This paper is devoted to presenting a systematic knowledge representation method of principle solution based on semantic network model. For the expression of product knowledge, the semantic object, constraints and their relationships among the expression of the semantic object network model are proposed step by step. Then the principle solution representation model based on semantic network model is put forwards. The knowledge representation of a car is given as an example, which demonstrates that this method is obviously helpful for knowledge-based design system and product innovation.
Numerical Simulation for the Milling of Alluminum Alloy Thin-Wall Workpiece with Two and Four Flutes Helical Cutter
Authors: Yuan Ping , Dong Hui Yue
Published: October 2010

In the milling process of thin wall workpiece, the more cutter flutes, the high metal remove ratio can be gotten. Milling forces with two-futes and four-flutes milling cutter were anlysised and compared using finite element method. The possibility and advantage of machining thin wall workpiece with four flutes milling cutter was introduced. The four flutes cutter can improve the metal remove ratio, and cutting force is more uniform in general.