bluuebunny/crossref_metadata_2025 huggingface dataset:
Damping Characteristics Simulation and Test Research of Vane Damp
Authors: Wang Wen Rui , Chen Han , Yan Xiao Qiang , Yang Bo
Published: February 2012

A new hydraulic model based on the structure analysis of the vane damp was established , which can be given the damping parameters directly. Based on damping force and velocity input test data, the parameters about the hydraulic model are identified by least squares fitting method,which is using to study the damping characteristics .Each parameter has its own physics meaning not only the math way, but also the physical influence. The method can be reduced the vane damp process and fix error. In the different temperature, comparison of the test data and results of calculation with the fitting parameters shows that the parameters are correct and the method is valid. Vane damp design and character analysis can be supported and the damping characteristics simulation method can be extended.
Analysis of Vane Hydraulic Damp Static Seal Mechanism and Performance Influencing Factors
Authors: Wang Wen Rui , Sun Zhi Hui , Yan Xiao Qiang , Jiang Qi
Published: February 2012

Based on the performance of Vane hydraulic damp O-ring seal ,simulation about the O-ring seal was applied by nonlinear finite element analysis method. The factors influencing sealing performance are considered, such as initial compressibility, sealing materials. Applying the method, the seal structure was designed and optimized. At the same time, the sealing performance was improved, and the contract pressure was increased. The finite element analysis method can be effectively used to solve nonlinear material and sealing failure problem for the seal design, optimization and performance analysis, which provide a new approach and theoretical guidance to the rubber seal research. The seal material and compression ratio are both great influence on the sealing performance , which should be based on working conditions to select the appropriate sealing materials.
Position and Orientation Analyses of Mechanism by PHCpack Solver of Homotopy Continuation
Authors: Xin Hong Bing , Huang Qiang , Yu Yue Qing
Published: February 2012

Mechanism analysis and synthesis commonly used analytic method and graphical method, etc., but the homotopy method has high efficiency in nonlinear analysis of mechanism. This paper applies the homotopy continuation method PHCpack solver to solve mechanism position and orientation, and draws the mechanism configuration according to the results obtained, the relative error of numerical results to exact solutions shows that the homotopy continuation method PHCpack solver can provide sufficient accuracy of mechanism position and orientation analysis, and meet the engineering needs.
Research on AC Short-Circuit Transfer Low-Energy Welding Technology
Authors: Huang Peng Fei , Lu Zhen Yang , Liu Xue Chao , Gu Jing Mao
Published: February 2012

The one cycle AC short-circuit transfer welding method is a new type of low-energy welding method, which could flexible control the welding process on the energy distribution of basement material and wires by changing the time of the polarity of the EN. Tests showed that the 1.0mm thin sheet welding, and welding process stability, beautiful weld bead, and small spatter could be achieved successfully by this one cycle AC short-circuit transfer welding method.
A Nonlinear Fuzzy Control Modeling Method Using Evolutionary Algorithm
Authors: Teng Ping
Published: February 2012

Although fuzzy control has been proven to be effective in control applications, the same is not true in fuzzy modeling. Fuzzy modeling in process control applications lack many other techniques in terms of applications and innovations. In this paper, modeling of a real process control rig using fuzzy modeling tuned by EA with a combination of the RLS has been proposed.
Investigation on the Freeze Casting Porous Al2O3 Ceramic Bodies Infiltrated with Nb-Ti-Al-Cr Alloy by Pressureless Infiltration
Authors: Chen H.M. , Luo M. , Wang H.C. , Fu P. , Yang D , Lin X.X. , Li X.
Published: February 2012

This paper adopted freeze casting method to prepare porous Al2O3 ceramic bodies with different volume percentage and interconnected pore channels as the preform. The porous Al2O3 ceramic bodies were pressureless infiltrated with Nb-35Ti-20Al-10Cr alloy (atom percentage, at%) by using electromagnetic induction furnace. The results indicated that there is a well wettability between Nb-35Ti-20Al-10Cr melt and porous Al2O3 ceramic body. And it would be possible to infiltrate Nb-35Ti-20Al-10Cr melt into porous Al2O3 ceramic body through pressureless infiltration. The microstructure observation for the Nb-35Ti-20Al-10Cr/Al2O3 composites demonstrated that it was still retained the layer structure characteristics of the preform. The Nb-35Ti-20Al-10Cr melt was filled into the interconnected pore channels existed in the porous Al2O3 ceramic bodies and the Nb, Ti, Al, Cr alloy elements diffused into the reinforced Al2O3 particles during pressureless infiltration.
The Way of Obtain C6H10O+ Fragments Laser-Induced by C7H12O+ Excited State
Authors: Chen Hong Bin , Zhu Ying , Wu Jie , Wu Di
Published: February 2012

We issue the theoretical calculation of C7H12O+ excited state, the corresponding vibration mode is given by the Gaussian03 calculation; In the analysis of vibration mode, it gives the possibility of C7H12O+ dissociation into fragments and the corresponding fragment analysis. In order to obtain relevant data of the fragments dissociation mechanism, we take the way analysis of C6H10O+ ion fragmentation as an example, then the bridge of experiment and theoretical calculations will provide a reference basis.
Cantalever Protection Aluminum Profiles Extrusion Die Design Method and Numerical Simulation
Authors: Pan Jian Yi , Wang Yao , Zhou Zhao Yao , Dong Shou Bin
Published: February 2012

In order to improve the service life of extrusion dies with long cantilever structure, a design scheme of porthole die for half-hollow profiles with long cantilever was introduced. Using numerical simulation method, compared with conventional method for the half-hollow porthole design method of a typical profile die model, the equilibrium of the material flow at the outlet, the stress and deformation of the die were analyzed in detail. With selection of the cantilever thickness shrinkage as the objective function, experiment was done to verify the result of simulating analysis. The results indicated that there was only little difference for the equilibrium of material flow between the two design schemes, but the stress load and deformation of the design scheme were greatly improved.
A Simple Method to Estimate the Fatigue Crack Growth Life of Repaired Pipes with Composite Patches
Authors: Hosseini-Toudeshky Hossein , Ghaffari Mir Ali
Published: February 2012

In this paper, a simplified method is performed to predict the fatigue crack growth life of repaired pipes by glass/epoxy composite patches. For this purpose, an already developed automatic procedure by the authors is adapted to handle 3D crack growth analyses of repaired pipes subjected to internal cyclic pressure. The analyses are performed for offshore pipes made of low-strength steel containing an initial fatigue corrosion crack and repaired by glass/epoxy composite patch. Finally, an equation is presented here suggesting a point along the thickness of a repaired pipe in which, the calculated fatigue crack growth life based on the fracture parameters of that point in a simple uniform crack growth modeling along the pipe thickness (UCG) is almost equal to the calculated fatigue life in non-uniform crack growth analysis (NUCG) or a real crack-front modeling approach.
The Preparation and the Properties of CS/PVP Composite Hydrogel Microspheres
Authors: Liu Cui Yun , Wu Feng Min , Yao Da Hu , Wang Yue , Zhang Yu Qing
Published: February 2012

According to the gelatification of sodium hydroxide ethanol solution, the chitosan (CS)/polyvinylpyrrolidone (PVP) composite hydrogel microspheres have been prepared in this paper. Meanwhile, the influence of PVP content and PH on the swelling property and the adsorption Cr(Ⅵ) effect of CS/PVP hydrogel microspheres has been also discussed. The results have shown that the introduction of PVP has significantly improved the swelling property of CS. When the CS content is 2.5% and the PVP content is 5%, the swelling rate of microspheres will be the maximum. The swelling property and the adsorption property of microspheres have shown certain pH sensitivity. And the SEM has also indicated that the inside of CS/ PVP composite hydrogel microspheres is the loose network structure, which is conducive to the swelling and the adsorption.
Photocatalytic and Self-Cleaning Properties of TiO2-Cu Thin Films on Glass Substrate
Authors: Sangchay Weerachai , Sikong Lek , Kooptarnond Kalayanee
Published: February 2012

TiO2-Cu thin films containing 0 to 1%Cu coated on glass slides were prepared by sol gel-dip coating method. The prepared thin films were synthesized at the temperature of 400 ◦C for 2 h with a heating rate of 10◦C/min. The microstructures of synthesized TiO2-Cu thin films were characterized by XRD, FT-IR and SEM. The photocatalytic activities of TiO-2Cu thin films were tested using methylene blue (MB) solution under UV irradiation. Finally, the self-cleaning property was evaluated by means of contact angle of water droplet on the films. The results show all samples have the thickness in range of 1 um and surfaces are dense with a large surface area. It can be noted that TiO2-1.0Cu thin films were found to give the highest photocatalytic efficiency and exhibited self-cleaning effect (small contact angle, 17°) under UV irradiation.
Joining of 1100 Al Alloy to AISI 1045 Carbon Steel by Friction Stir Welding
Authors: Karimi Namdar , Shakeri Mohsen , Habibnia M. , Nourouzi S.
Published: February 2012

Joining of dissimilar materials like Al alloy to carbon steel is attractive for industrial applications such as automotive industry. In this research, Friction Stir Welding (FSW) has been used to joint between dissimilar materials like 1100 Al alloys to AISI 1045 carbon steel. In this paper, the effect of rotational speed, feedrate and offset of tool are investigated on mechanical and metallurgical properties of the welding. The joints were evaluated by mechanical testing and metallurgical analysis. Metallurgical properties carried out by optical microscopy and Scanning Electron Microscopy (SEM) and mechanical properties conducted by the joint strength. Finally, optimum value of tool rotational speed and feedrate were obtained 710 rpm and 28 mm/min respectively and the best offset value of the tool obtained 1.5 mm in the Al alloy. Tensile strength properties of Al1100/1045 carbon steel joints were found to be approximately 20% lower than that of the Al 1100-H14 alloy base metal
Microstructure and Hardness Property of Internally Oxided AgCdO Alloy
Authors: Lee Hyo Soo , Shin Hyung Won , Jung Taek Kyun , Kim Tae Bum , Lee Min Ha
Published: February 2012

Microstructure and hardness property of AgCd alloy internally oxided at 973K for 1 h - 24 h with O2 atmosphere of 3 atm was investigated. Band typed CdO phase was formed at grain boundaries, and particle typed CdO phase was formed at grain interior. In this alloy, it was found that oxygen adsorpted at surface diffuses to interior through grain boundaries, and it subsequently diffuses into grain interior during internal oxidation. No Ag exduation was found in this alloy. The thickness of oxidized layer increased with increasing holding time at given temperature. Hardness of the oxidation zone was 125 ± 5 Hv, which value is higher two times than that of the oxidation free zone. The higher hardness of oxided region than the oxidation free zone was attributed to the dispersion strengthening by CdO particles.
Optimization of Flow Control Device in 300,000t Heavy-Duty Casting and Forging CCM Tundish
Authors: Xiong Wei , He Zhu , Wang Guo Qiang
Published: February 2012

Fluid flow fields of molten steel were calculated under the different setting of flow control device in the tundish, and the characteristics of flow were investigated by residence time distribution curves (RTD). The results show that the response time and peak time are small without the flow control device installed in the tundish. A suitable design of flow control device could extend the mean residence time of molten steel in the tundish, and increases the volume of piston-type flow zone with decreasing the volume of dead zone. It is found that the effect of flow control adopting turbulence inhibitor 2# and dam is the best. The volume fraction of the dead zone is reduced from 54.19% to 16.51%, and the proportion of dead zone becomes much lower. The dominant role of the dead zone has been replaced by that of the piston-type flow zone. A satisfactory effect of flow control could be achieved by adopting wall 3# if a turbulence inhibitor is not available, and the volume fraction of the dead zone is decreased to 24.32%.
High Order Numerical Study of Gas Squeeze Film with Flexural Boundary Condition
Authors: Li Jin , Wu Jing , Ren Jia Qi
Published: February 2012

Ultrasonic levitation system based on Near Field Acoustic Levitation is investigated in this study. A disc is levitated at a height much smaller than the acoustic wavelength where NFAL effect is dominant. A high-order analytical and numerical study on the levitation force induced by gas squeeze film is performed. By taking into account the modal solution on the vibrator whose disunity of the surface displacement can not be ignored, detailed boundary condition of gas squeeze film can achieve a high accuracy in final calculations of time-averaged pressure distribution, load capacity and stiffness of the system. A finite element analysis is compared with analytical solution. By discussing NFAL behavior in gas squeeze films, explanation of essential levitation characters in flexural vibrators is presented, which is important for future study on wafer’s non-contact transportation based on acoustic levitation.
Post-Buckling Analysis of FGM Beam Subjected to Non-Conservative Forces and In-Plane Thermal Loading
Authors: Zhao Feng Qun , Wang Zhong Min , Zhang Rui Ping
Published: February 2012

Based on the Kirchhoff large deformation theory, the post-buckling behavior of right movable simply supported FGM beam subjected to non-conservative forces and in-plane thermal loading was analyzed in this paper. The temperature-dependent and spatially dependent material properties of the FGM beam were assumed to vary through the thickness. The nonlinear governing equations of FGM beam subjected to a uniform distributed tangential load along the central axis and in-plane thermal loading were derived. Then, a shooting method and Runge-kutta method are employed to numerically solve the resulting equations. The post-buckling equilibrium paths of the FGM beam with different parameters were plotted, and the effects of non-conservative force, temperature, gradient index of FGM on the post-buckling behavior of right movable simply supported FGM beams were analyzed.
Nanocrystalline Silicon Films with High Conductivity Prepared by Hot Wire Chemical Vapor Deposition
Authors: Liu Chueh Yang , Yun Yao Ting , Hsieh Ping Chen , Hsu Jen Ken , Lien Shui Yang
Published: February 2012

Nanocrystalline silicon (nc-Si:H) grown by hot-wire chemical vapor deposition (HWCVD). We report on the effects of B2H6 doping ratio on the microstructural and optoelectrical properties of the p-type nc-Si:H thin films grown by HWCVD at low substrate temperature of 200 °C. An attempt has been made to elucidate the boron doping mechanism of the p-type nc-Si:H thin films deposited by HWCVD and the correlation between the B2H6 ratio, crystalline volume fraction, optical band gap and dark conductivity. Characterization of these films from Raman spectroscopy revealed that the high conductive film consists of mixed phase of nanocrystalline silicon embedded in an amorphous network. A small increase in B2H6 doping ratio showed marked effect on film microstructure. At the optimal condition, high dark conductivity (8 S/cm) with high optical band gap (~2.0 eV) was obtained.
Preparation and Mechanism of High Dosage Fly Ash Cement
Authors: Wang Rui Gang
Published: February 2012

The activate effect of various activator on fly ash was studied according to the comparative tests of cement strength. The result shows that the sulfate activator and alcohol amine activator composite mixture has the best activate effect under the reasonable mix ratio. The composite mixture can obviously affect fly ash cement strength, and under the 50% mixing amount of fly ash, the 3d strength of cement is improved by 30% to 50%, and the 7d strength of cement is improved by 20% to 30%. Activate mechanism of the composite activator was studied through the XRD, SEM and other microscopic testing methods.
Application of Fractal Dimension Feature to Recognition of Surface Defects on Hot-Rolled Strips
Authors: Xu Ke , Zhou Peng , Yang Chao Lin
Published: February 2012

Because steel strips are covered with scales and water during hot-rolling, it is difficult to recognize the defects from images of hot-rolled strips through conventional methods. Principles and characteristics of fractal dimensions were studied, and computation of the fractal dimensions of the defect images with Peleg Covered Carpet is presented. Fractal dimensions of piecewise linearly transformed and smoothed images were used as features for classification of defects. These features were inputted to train the AdaBoost classifier. Experiments with samples of pimples, shells and scales from a real surface inspection system of hot-rolled strips showed that it is effective to recognized scales from other defects, and the total classification rate of this method is higher than 90%.
Research on Mechanical Model of EPDM Insulation Charring Layer
Authors: Xu Yi Hua , Hu Chun Bo , Zeng Zhuo Xiong , Yang Yu Xin
Published: February 2012

The coupling effect of physics, chemistry and mechanics is through charring layer in the process of ablation of the insulation material. Description of the structure and mechanical properties of charring layer is the critical factor to numerical computation for foretelling the ablation of insulation material. The characteristic of charring layer structure of EPDM insulation at sorts of ablating condition were analyzed, and based on characteristic of porous medium of charring layer, the mechanical model with porosity as parameter was modeled by using theory of solid porous medium. According to the intensity determination of charring layer, the coefficient of intensity model was determined, then, the failure criterion of charring layer was set up, which can provide the mechanical parameters of charring layer for numerical computation to foretell the ablation of insulation material.
Computer Simulation of Cylindrical Shell Penetrated by Rigid Projectile
Authors: Yu Xue Hui , Han Zhi Jun , Kang Zuo Yi , Lu Guo Yun , Liu Zhi Fang
Published: February 2012

Computer simulation of cylindrical shell subject to lateral impact by rigid projectile is carried out. The effects of three kinds of typical rigid projectiles, geometric parameters of cylindrical shell and constraint conditions on critical speed are analyzed. The results indicate that the shape of projectile and size of cylindrical shell have a great influence on penetration, and the tapered projectile has a minimum critical speed. The influence of constraint conditions on penetration has a great relationship with thickness of cylindrical shells; energy distribution varies with different thickness of cylindrical shells.
Fabrication of Nano-Fibrous Poly(L-Lactic Acid) Scaffold Enhanced by Silane Modified Chitosan Fibers
Authors: Wang Xue Jun , Lou Tao , Lang Xiu Ting , Song Guo Jun
Published: February 2012

In this study, A PLLA/silane modified chitosan fiber composite scaffold was sucessfully prepared using thermal induced phase separation method. The PLLA was chemically coupled with chitosan fiber surface using γ-methacryloxypropyl-trimethoxysilane.The composite scaffold had a nano-fibrous PLLA matrix (fiber size 200-750 nm), an interconnective pores ((1-6 μm), high porosity (>90%). Introduced surface modified chitosan fibers into PLLA matrix, it significantly enhanced the nano-fibrous scaffold. The new nano composite scaffold is potentially a very promising scaffold for tissue engineering.
A Study of Macrogeometrical Deviations in the Dry Turning of UNS R56400 Ti Alloy
Authors: Salguero Gómez Jorge , Gerez Julia , Batista Moises , Garófano J. Enrique , Marcos Bárcena Mariano
Published: February 2012

The UNS R56400 is a Titanium alloy commonly used in the aircraft industry. This alloy can be processed by machining depending on its final application. Drilling and turning are the most usual machining processes for working this alloy. Aerospace requirements involve high quality levels and, if possible, an on-line monitoring in order to preserve the workpiece design conditions. The machining process can be monitored by different methods. One of the most single methods involves the analysis of the finishing quality of the workpieces. This analysis is usually related to micro and macro geometrical considerations. In this paper a study of the finishing quality of dry turned UNS R56400 Ti alloy has been achieved. This study has been carried out based on the analysis of straightness and parallelism deviations as functions of cutting parameters, such as feed and cutting speed.
Effect of Lattice Distortion Modification Processing on Crystallinity and Orientation of Ramie Fiber
Authors: Sun Yi Ze , Zhu Zi Na , Meng Zhuo , Gao Xiao Ping
Published: February 2012

In order to test whether the crystallinity and orientation of ramie fibers have changed after they are treated by the lattice distortion modification processing technology, this paper does some experiments on it. Firstly, process ramie fibers by the lattice distortion modification processing equipment. Then use X-ray diffraction method to determine the crystallinity and orientation of pristine and modified ramie fibers. Finally analyse the effect of lattice distortion modification processing on the lattice structure of ramie fiber. The experimental results show that the lattice structure of ramie fiber has changed after modification processing, with crystallinity, grain size decreasing obviously and orientation slight descent, which make ramie fibers appear softer and more puffy from macrocosmic perspective.
Synthesis and Characterization of UV-Thermal Dual Hybrid Curable Organosilicon Modified Epoxy Monoacrylates
Authors: Liu Hong Bo , Lin Feng , Zhang Wu Ying
Published: February 2012

New UV-thermal dual hybrid curable organosilicon-modified epoxy monoacrylates (OMEMA) were synthesized in this study. The changes of NCO groups during the synthesis process of OMEMA were measured by chemical titration method, and its Fourier Transform Infrared (FTIR) spectra were investigated. The results indicate that organosilicon chain segments can be grafted onto the epoxy monacrylates (EMA) by the reaction of NCO and OH groups. The FTIR of OMEMA show that it contains both double bond of acrylic ester (UV curable) and epoxy groups (thermal curable).
Finite Element Analysis of Thermal Effect on Large Thick Titanium Alloy Electron Beam Welding with Different Focus
Authors: Zhang Bing Gang , Chen Guo Qing , Guo Wei , Shi Ming Xiao
Published: February 2012

A composite heat source model composed of Gaussian surface heat source and rotational paraboloidal body heat source have been established to simulate the temperature field of 20mm TA15 titanium alloy. The results show that the simulated peak temperature of molten pool during surface focus welding is 3200°C, while the simulated peak temperature of molten pool during lower focus is 2700°C, and the whole surface temperature of surface focus welding is higher than that of lower focus welding, while the whole inner temperature of surface focus welding is lower than that of lower focus. The simulated temperature gradient in the direction of depth during surface focus welding is large, but the simulated temperature gradient in the direction of depth during lower focus welding is small. The simulated result was verified by the thermocouple and contrast of weld cross section morphology. The simulated thermal cycle curves are well consistent to the results tested by thermocouple, and there is a good consistency between the simulated molten pool morphology and the real weld morphology, they verify the accuracy of finite element model.
Study of Static Recrystallization Microstructure Evolution of 304 Stainless Steel
Authors: Zhao Xiao Dong , Liu Jian Sheng , Chen Hui Qin , Duan Xing Wang , He Wen Wu
Published: February 2012

The effect of various deformation degree and temperature on static recrystallization of 304 stainless steel during two-passes hot compression deformation with the strain rate of 0.1s-1 was investigated by use of Gleeble-1500D thermo-mechanical simulation. It is indicated that deformation degree is the most obvious factor to static recrystallization. Besides, the grain sizes after deformation were also measured by metallographic method. The results show that the grain sizes decreased dramatically with the conditions of deformation temperature (1050°C), holding time (30s) and total deformation degree (0.35). The result has provides the corresponding scientific basis for the quality forecast of 304 stainless steel during hot thermoplastic deformation.
Influence of MgO on Sintering and Property of Belite-Barium Calcium Sulphoaluminate Cement
Authors: Lu Ling Chao , Wang Shou De , Wang Hui
Published: February 2012

The effect of MgO on performance of belite-barium calcium sulphoaluminate cement (B-CBAS) was investigated through orthogonal tests. The results show that the formation of C3S can be improved at low temperatures by mixing MgO. SO3 decreasing the viscosity of fused mass in sintering process was beneficial to solid solution of MgO in B-CBAS clinker. The solid solubility of MgO in B-CBAS was higher than that of Portland cement, which indicated that high-magnesium limestone can be used in B-CBAS. Even MgO content reached 5.14%, the soundness of B-CBAS was still in safe, whose compressive strength at 3d and 28d curing age were 49.1MPa and 81.9MPa. This indicated that this kind of cement has good mechanical properties.
Research of Engine Oil Change Period about Shenzhen LNG Bus
Authors: Meng Fan Sheng , Huang Wen Wei
Published: February 2012

The article aims at Shenzhen LNG bus for the engine oil change period research. We sample the vehicle new and replaced oil, test the quality indicators in determining the parameters of the engine oil, analyze the engine oil,s kinematic viscosity change rate (100 °C), flash point (closed), decreased rate of base value, acid value increment ,pentane insoluble, water, iron, copper, aluminum，silicon content and other items for determining the engine oil drain interval. Based on the results obtained reasonable drain cycle for LNG bus, come to appropriate use recommendations and repairing guidance for LNG bus, and instruct the LNG bus choose suitable engine oil drain cycle in order to extend the engine oil life.
Numerical Study on Dispersion Characteristics and Damage Results of Pre-Fragment Warhead
Authors: Zhou Nan , Wang Jin Xiang , Yang Rui
Published: February 2012

The dispersion characteristics, damage region and destroy results of typical defending materials by pre-fragment warhead using explosively driven were numerical studied by non-linear finite code of LS-DYNA with fluid-structure interaction algorithm, meanwhile, the influence of different detonation types and explosive properties on dispersion characteristics and damage results of kinetic energy rod were analysed. Results show that: 1.fragments disperse symmetrically with greater damage region when center detonation and line detonate are adopted, and the dispersion velocity of fragments reach the maximum when line detonate is used; 2.explosive of higher detonation velocity in favour of improving the initial velocity of fragments, strengthing the damage ability; 3.the penetration kinetic energy of fragments increase with the decrease of axial angle between fragment and damage target.
Study on Dynamic Stability of Large-Scale Underground Cavern Group during Construction Period of Hydropower Station
Authors: Nie Wei Ping , Shi Chong
Published: February 2012

Taking excavation and supporting of surge tank large-scale underground cavern group of Nuozhadu hydropower station as example, the stability of surrounding rock is analyzed systematically, and the best lining scheme is obtained. Through primary supporting calculation, the displacement and the small main stress increases continuously with excavation of cavern; the rock-point safety factor of decreases continuously with excavation of cavern; the displacement, the small main stress and the rock-point safety factor soon changed when the surrounding rock unloaded suddenly, therefore, the surrounding rock must be supported timely. After excavation, the maximum total displacement is 10.57mm, the maximum tensile stress is far less than the tensile strength of surrounding rock, and the minimum safety factor of key point does not satisfy the requirement of standard; the surrounding rock surface will be broken but not large-area damage basis of excavation. The key point’s safety factor changes and the safety factor satisfies the standard requirement only when the elevation of the second lining larger than this key point. According to lining scheme comparison, the scheme that concrete of surge tank pouring to elevation 625.5m is the most economic and reasonable lining scheme for this engineering.
Axial Force Studies of ESPCP System Based on Triz Theory
Authors: Li Wei Xiang , Wang Shi Jie
Published: February 2012

The configuration characteristics and actual working condition of the downhole unit of existing electrical-submersible-motor driven progressing cavity pumping (ESPCP) system are analyzed in detail. Appling the methods and the main tools of Triz theory, conflicting analysis is performed for the axial bearing capacity affecting submersible depth and operational lifespan of downhole unit. The parameters of physical and technical contradictions are standardized. Appropriate principles of invention are selected through contradiction matrix analysis and a more reasonable innovation design project of the ESPCP system configuration is developed. As such, the axial bearing capacity of downhole unit has been effectively improved.
Structure of Combustion Enhancement on Impinging Diffusion Flame
Authors: Leu Jai Houng , Su Ay
Published: February 2012

For the purpose to clear obverse the impingement and entrainment of the impinging diffusion flame, numbers of the tests are executed under various sets of momentum ratios in this paper. The oxidizer-fuel impinging flames shorten the fully development length. The peak temperature distributions are also greater than that of pure methane impinging flame. Furthermore, its flame width in YZ plane is thicker than that of the pure impinging flame. This effect is more obvious under lean combustion condition. Also, nitrogen gas in the mixture can increase the mixing rate.
Modeling of Thrusting Trajectory for Articulated Needle
Authors: Wang Yi Zhong , Zhao Qi , Zhang Rui , Chen Yong Hua
Published: February 2012

Comparing with the needles having been studied previously, an articulated needle is more flexible and easier to be steered. In this paper, the sections of an articulated needle are assumed as rigid rods, and an articulated needle is simplified as a spatial linkage mechanism with open link chain. The positions and poses of needle sections are analyzed using the kinematic principle of series robots. The transformation matrixes of positions and pose of needle sections are calculated. A series of coordinate positions of needle sections are got and used to analyze the inserting trajectories of an articulated needle.
Towards an Articulated Needle
Authors: Wang Yi Zhong , Yin Qi Long , Liu Cheng Jie , Chen Yong Hua
Published: February 2012

Needle is a kind of basic medical instruments in minimally invasive surgery. A thin and long needle is inserted into a human body through the skin to perform diagnosis and treatment tasks. In order to improve the steerability of a needle, articulated needle is proposed in this paper. An articulated needle consists of a head with a bevel-tip, several articulations and several sections. Articulations are much easier to be bent, which allows proposed articulated needle to be more easily controlled to achieve a complex curved trajectory. The structure of the articulated needle is investigated for improving its bending performance. The influences of the angle of bevel-tip, the sectional dimension of sections, the number of articulations, the maximum bending angle of articulations, and the distribution of articulations on the bending performance of the needle are studied, which provide the basis for path planning and navigation of an articulated needle.
The Effect of an External AC or DC Electric Field on Collision and Agglomeration in an Electrostatic Agglomerator
Authors: Zhang Xiang Rong , Wang Lian Ze
Published: February 2012

This article simulated the collision and agglomeration between bipolarly charged particles in an electrostatic agglomerator. The EHD turbulent flow was solved and the flow parameters were extracted a priori. The particle initial charge was obtained by tracking particles with a certain diameter in the charging zone. When simulating collision and agglomeration in the agglomerating zone, the initial charge on a particle was sampled from the charge distribution by statistical analysis. The classical stochastic model for calculating collision between neutral particles was extended to calculate collision between charged particles, and the effect of particle charge on collision and agglomeration was embodied in the agglomeration criteria. The effect of an external DC and AC electric field on the collision and agglomeration was investigated.
Impact Behaviour of Composite Materials by Using Low and High Speed Impact Tests
Authors: YALÇIN Enver Bulent , Gunay Volkan , Marsoglu Muzeyyen
Published: February 2012

The study presents the need for instrumented testing to optimizing materials against impact forces. The objective of the study is how the impact behaviour of composite materials is investigated by slow and high speed impact tests. Instron Dynatup 9250HV and Instron Dynatup 8150 Impact test machines (Fig.1.) are used which are located in TUBITAK-MRC, Materials Institute , Impact Test Laboratory". The damage process in composite materials under low and high velocity impact loading and the impact energy-displacement properties of the composite materials were investigated. Composite samples were produced by woven fabrics. The results are given as graphs and tables. The Impulse Data Acquisition software is used to send the data to computer.
Tribological Properties of Vanadium Nitride Coated AISI 52100 Steel
Authors: Şen Uğur , Uzun Murat , Şen Şaduman
Published: February 2012

In the present study, the wear and friction behaviour of vanadium nitride coated AISI 52100 steel against hardened AISI D2 steel disc was studied using ball-on-disc arrangement. Vanadium nitride coating treatment was performed on pre-nitrided AISI 52100 steel balls using thermo-reactive diffusion techniques. The presence of VN and V2N phases in the coating layer was confirmed by X-ray diffraction analysis. Friction and wear tests were carried out at dry test conditions under 2.5 N, 5 N and 10 N loads at 0.1 m/s, 0.2 m/s and 0.3 m/s sliding speeds. The results showed that the friction coefficient values of vanadium nitride coated AISI 52100 steel balls against hardened AISI D2 steel disc are changing between 0.49 and 0.71, depending on test conditions. The wear rates of the vanadium nitride coated AISI 52100 steel is ranging from 6.704×104 mm3/m to 2.619 × 106 mm3/N m. In general, the wear rate increased with the increase in load and sliding speed.
Zirconia-Hydroxyapatite Composite Coating on Cp-Ti Implants by Biomimetic Method
Authors: Yoruç A. Binnaz Hazar , Karakas Aysu , Elkoca Oktay , Ipek Yeliz Koca
Published: February 2012

Hydroxyapatite (HA) is the major component of the natural hard tissues such as teeth and bone. It has been studied extensively as a candidate biomaterial for its use in prosthetic applications. However, the main weakness of this material lies in its poor mechanical strength which makes it unsuitable for load-bearing applications. On the other hand zirconia (ZrO2) powder has been widely studied because of its high strength and fracture toughness and good biocompatibility. Therefore, the addition of zirconia phase into HA will improve the mechanical properties and biocompatibility of HA ceramics. The present study focused on coating of HA-ZrO2 on commercially pure titanium (cp-Ti) using novel biomimetic sol-gel method. The HA-ZrO2 coatings produced with BSG method were exhibited highly crystalline and pure structure. The coating thickness of the samples was not significantly influenced by the change in gelatin concentration and volume. It was concluded that the suggested coating method is a useful method to produce a biomimetic coating layer on the cp-Ti sample surfaces.
Nonlinear Dynamic Buckling of FGM Shallow Conical Shells under Triangular Pulse Impact Loads
Authors: Lin Jie , Deng Chao , Xu Jia Chu
Published: February 2012

In this paper, nonlinear dynamic buckling of FGM shallow conical shells under the action of triangular pulse impact loads are investigated. The nonlinear dynamic governing equation of symmetrically FGM shallow conical shells is built. Using Galerkin method, the nonlinear dynamic governing equation is solved, and the nonlinear dynamic response equation of symmetrically FGM shallow conical shells is obtained. The Runge-Kutta method is introduced to numerically solve the nonlinear dynamic response equation and the impact response curve is achieved. Budiansky-Roth motion criterion expressed by the displacement of the peak of the shell is employed to determine the critical impact buckling load. The influences of geometric parameters and gradient constants on impact buckling are discussed as well.
Fabrication and Photocatalytic Activities of TiO2 Nanotube Arrays
Authors: Tu Ya Fang , Fu Qiu Ming , Niu Xiao Juan , Sang Jian Ping , Tan Zhi Jie , Zou Xian Wu
Published: February 2012

TiO2 nanotube arrays were prepared using template-based liquid phase deposition method. Their morphologies and structures were investigated by scanning electron micro¬scopy, transmission electron microscopy and X-ray diffraction. The photocatalytic properties of the samples were evaluated with the degradation of methylene blue under UV irradiation. It was found that the TiO2 nanotube arrays annealed at 900 °C showed the highest photocatalytic activity.
Dynamic Behavior Analysis of Three-Span Rotor-Bearing System with Rub-Impact Fault
Authors: Zhang Song He , Luo Yue Gang , Wu Bin , Wen Bang Chun
Published: February 2012

The dynamic model of the three-span rotor-bearing system with rub-impact fault was set up. The influence to nonlinear dynamics behaviors of the rotor-bearing system that induced by rub-impact of one disc, two discs and three discs were numerically studied. The main influence of the rotor system response by the rub-impact faults are in the supercritical rotate speed. There are mutations of amplitudes in the responses of second and third spans in supercritical rotate speed when rub-impact with one disc, and there are chaotic windows in the response of first span, and jumping changes in second and third spans when rub-impact with two or three discs.
Realization of the Railway Electrical Equipment Maintenance Automation System Based on the Workflow and Dynamics
Authors: Li Gang , Ma Yan Ning , Yang Xiu Qian , Han Zheng Qing
Published: February 2012

For guaranteeing the safety of railway operating, this paper puts forward a new theory of electrical equipment maintenance. Set up uniform data standard and data format, and maintain the electrical equipment information through the computer network; created a new equipment maintenance plan base on the information, and controlled and monitored the situation and completion of maintenance operation; by dint of the workflow mechanism, achieved the normative executing of complicated maintenance flow, and reduced workload; used SMS alerts for approval, and made it convenient to carry out the maintenance plan execution. This method of electrical equipment maintenance can fulfill the demands of electronic, automated and process-orienting.
A Fast Subdividing Circuit Design for Moire Frenge Grating with Smart Materials and Structures
Authors: Song Nuan , Wu Yi , Quan Wei , Zheng Wei
Published: February 2012

The key problem for improving the precision of grating sensor is the subdivision technolgy. According to the instable condition of traditional monostable trigger subdivision circuit works on fast condition, this paper adopts CPLD to judge the logic signal, can identify direction, subdivide and count. In addition, we have introduction of the exterior synchronous clock .The technology not only overcome the instable situation but also improve anti-jamming of circuit system .It has been proved that the method get the better effort in practice.
Simulation Analysis of Light Off-Road Vehicle's Body Frame during Airdropping
Authors: Yue Jing Tao , Tang Li , Guo Bo Hai
Published: February 2012

A guide line of the vehicles' performance during impact is given, and a design of airdrop cushion system for all the off-Road Vehicles is established in this paper. Based the software of ANSYS, it does simulation analysis for the several blue prints of the beehive cushion which are used in the practice.
Study on Lithium Iron Batteries Synthesis
Authors: Zhao Dong Mei , Liu Xue Peng
Published: February 2012

The heat treatment temperature on the influence of the material structure and properties is discussed. At 710 °C the synthesis of LiFePO4 crystallization is complete, morphology, and particle size is moderate, which has the best electrochemical performance. Sphere of lithium iron phosphate is synthesized by ethylene glycol solvent under low temperature heat synthesis method, which can give a relatively high tap density of 1.6g•cm-3
Magnetorheological Flexible Clamp Experiment and Analysis
Authors: Zhao Dong Mei , Liu Xue Peng
Published: February 2012

A series of contrast curve are presented about magnetorheological flexible clamp and test results are analyzed to explain the phenomenon. Lattice transform plays an important role in magnetorheological material mechanics
Application Study of Costume Materials in Interior Decoration
Authors: Li Man , Hu Wei Ping
Published: February 2012

Through the successful application of the home improvement materials like ceramics and PVC materials in the costume design, the thesis analyzed costume materials’ adhibition in the interior decoration and introduced the nanofiber materials, milk fiber, phase-change materials as well as high-tech fabrics into the home fabric decorations so as to improve the comfortableness, health and security of home lives; and it also accorded with the green initiative and organic theme of the social development in the future.
Thermodynamic Analysis on the Precipitation of Crystalline Phase from LF Slag during Cooling Process
Authors: Lv Ning Ning , Su Chang , Yu Jin Kun
Published: February 2012

The precipitation of crystalline phase from LF slag during cooling process was discussed according to the thermodynamic analysis by using CaO-SiO2-Al2O3 system. The results showed that when the slag basicity was low, 2CaO•SiO2 (C2S) was precipitated firstly during the cooling process, and then it was followed by 2CaO•Al2O3•SiO2 (C2AS) and 12CaO•7Al2O3 (C12A7), and the precipitated crystalline phases existed uniformly in the slag. In the case of high basicity slag, 3CaO•SiO2 (C3S) and 3CaO•Al2O3 (C3A) with incongruent melting point temperature could be produced, and which would result in a non-uniform distribution in the slag.
The Study of the Optimum Blended Ratio of Soybean Protein Fiber/Polyester Blended Yarn
Authors: Yang Qing Bin , Sun Yong Jun
Published: February 2012

The strength and elongation, the distribution of the soybean protein fibers and the bending rigidity of the soybean protein fiber/polyester blended yarn are tested. By the analysis of the results, the optimum blended ratio of the blended yarn is determined by the multi-objective optimization method.
The Strength and Elongation of PLA Fiber Yarn
Authors: Yang Qing Bin , Dou Yu Kun
Published: February 2012

The PLA fiber is one of the green fibers. It is blended with Tencel fibers. The strength of the PLA fiber/Tencel blended yarn is tested. The relationship between the strength and the twist factor and the blended ratio is analyzed. The optimum blended ratio and the critical twist factor of the blended yarn is determined.
Application Property and Structural Characteristics of Bark Lignosulfonate Superplasticiser
Authors: Wang Zhe , Xue Jing Wen
Published: February 2012

The application property and structural characteristics of bark lignosulfonate (LS) was studied. Results showed that bark LS had perfect application property in concrete. The fluidity of cement paste was 214mm, which was 87.0% of commercial superplasticiser of naphthalene sulfonate; the loss on fluidity of cement paste of bark LS was very small, which was much better than that of naphthalene sulfonate. The loss on fluidity of cement paste of bark LS after 60 min was only 5.6%, but that of naphthalene sulfonate was 30.6%. Bark LS had low foaming capacity and high foam stability. Surface tension of 1% bark LS solution was 48.1 mN/m. Structural characteristics of bark LS was also studied. It showed that the reason that bark LS had good application property was that it had high content of hydrophilic sulfonic group, carboxyl group and phenolic hydroxyl group, and uniform molecular weight distribution.
Quality Classification Model of Material Products Based on Ordinal Logistic Regression
Authors: Mu Peng Fei , Zhang Dong Ling , Xu Xiao Mei , Liu Yang
Published: February 2012

It presents a proposed method for the development of quality evaluation and classification for material products, and shows the application of the ordinal logistic regression model and its advantages. It involved several steps: applying the linguistic information processing method, building the ordinal logistic regression model, differentiating and analyzing the quality evaluation to reach the quality classification result
Study on Inside and Outside Circumferential Defects of Pipes and Ultrasonic Guided Wave
Authors: Jiang Yin Fang , Guo Zhen Ning , Yan Yong Qi , Huang Qin
Published: February 2012

The difference between inside circumferential defects and outside circumferential defects was proved using the theory of reflection waves, the course of propagation and reflection from inside circumferential defects and outside circumferential defects in steel pipes was simulated with L(0,2) mode by the numerical simulation program ANSYS, and the curves of the reflection waves were obtained. The investigation indicated that the relationship between reflection coefficient of each kind of circumferential defects and the circumference of the defects was linear; in additional, it was found that the reflection coefficient of outside circumferential defects was a little higher than the reflection coefficient of inside circumferential defects; the difference between inside and outside circumferential defect became more obvious as the thickness of the defect increases. So the results provide a basis for detecting and distinguishing circumferential defects of pipes.