bluuebunny/crossref_metadata_2025 huggingface dataset:
Combustion Process’s Kinetics Study of Biomass and its Cellulose Based on Biomaterials in Material Engineering
Authors: Zhang Chuan Cheng , Lu Hai Jun , He Xiang
Published: September 2012

The combustion characteristics of some biomass samples, such as rice straw and its cellulose, were investigated. Non-isothermal thermogravimetry, where the sample was heated in air and the temperature of which increased at a linear rate of 10°C/min, 20°C/min, 30°C/min, was used to investigate combustion process of the biomass samples. The differences in the TG-DTG-DSC curves of the samples were determined and discussed in detail. Results showed that combustion process can be described in terms of first order reaction.
Study on Lanthanide Oxides Materials in Material Engineering with a New Method
Authors: Wang Xiao Li , Yu Da Wei , Han Xu , Zhao Xin Yu
Published: September 2012

In material engineering, the higher charge number of an element in a compound, the more strongly its atom attracts electrons. Hence, the polarizability is entirely different when it is in different valence states. Moreover, most elements are able to exercise more than a single coordination number in a given oxidation state. On the basis of ionization potential and effective ionic radius, some empirical expressions were proposed to predict the electronic polarizability and optical basicity of lanthanide oxides for the different coordination numbers (6-12). The estimated values are in perfect agreement with previously reported values in the literature. This work provides a simple and effective method to predict the electronic polarizability and optical basicity of lanthanide oxide
Analysis for Modeling of Molten Carbonate Fuel Cells Material Characteristics
Authors: Tian Yu Dong
Published: September 2012

The molten carbonate fuel cell (MCFC) is a difficulty in the research field of high-temperature fuel cells at present, and its strict hot start process and running status influence the material performance and life of the cell greatly. To deal with the problem, the MCFC mathematical modeling was analyzed firstly. Then a model of MCFC process based on material characteristics was advanced. Thirdly, the MCFC modeling structure, algorithm, and simulation applied the electrochemical processes were particularly presented. Finally, the results proved that it was fast and accurate, and provided the suitable model of MCFC system control at the view of application.
Growth Mechanism and Characterization of Porous CuS Microspheres
Authors: Xu Shuang , Song Nuan , Qiu Chang Li , Zhang Yao Ping , Wang Jian Feng
Published: September 2012

In this paper, a facile method was presented to fabricate CuS porous microspheres, which were formed by the intergrowth of CuS polycrystalline nanoslices. The obtained sample has been characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electronic diffraction (SAED), and scanning electron microscopy (SEM). On the basis of the experimental results, we proposed a self-assemble mechanism to elucidate the formation of CuS nanoslice structure.
Influence of Molecular Structure on Properties of Polycarboxylate Superplasticizers
Authors: Liu Ming , Lei Jia Heng , Du Xiao Di , Huang Bo
Published: September 2012

The properties of polycarboxylate superplasticizers(PCs) are related to their structures. For better understanding the different properties between PCs, their structures should be examined. In this paper, three kinds of PCs are synthesized by radical copolymerization method. The structure and property of PCs are studied by means of high performance liquid chromatography, zeta potential, water reducing rate and fluidity of cement paste. The results show that the conversion rate of reaction monomers is over 97%, and the reaction monomers are fully in the polymerization. The ester-type PCs has a higher water reduction capacity than the ether-type. At the same dosage, the adsorption and dispersion ability of ester-type PCs are stronger than that of ether-type PCs, yet the ether-type PCs has better slump retention performance in the cement pastes.
Hydration Activity of Ceramic Polishing Powder at Autoclaved Condition
Authors: Zhong Ming Feng , Su Da Gen , Zhao Yi Xiang
Published: September 2012

Hydration activity of waste ceramic polishing powder at autocalved condition were studied by IR, XRD, SEM and EDS in civil engineering. The results shown that autoclaved condition is beneficial to inspire hydration ability of polishing powder, the more active silicon and aluminium were dissolved, and they were converted into low Ca/Si ratio calcium silicate hydrate, whose ratio of Ca/Si was 1.58, and the compressive strength of autoclaved silicate product made by the ceramic polishing powder was higher than that of fly ash.
Rheological Characteristics on Solution of NMMO/Cellulose with Different Degree of Polymerization and its Combination
Authors: Li Jin Bao , Zhang Mei Yun , Xiu Hui Juan , Li Xin Ping
Published: September 2012

Impacts of temperature, shear rate, cellulose concentration and DP proportion on rheological behavior of cellulose/NMMO•H2O solution were investigated in this paper; especially put forward a method of mixing different DP cellulose at different proportion to discuss more accurately effect of DP. The results shown that the flow activation energy of 4% cellulose/NMMO•H2O was 24.45kJ/mol, and the temperature 85～115°Cwas suited for its processing. All kinds of cellulose solution with different DP were the pseudoplastic fluid, and had shear thinning characteristic, especially high DP. The cellulose concentration was higher, apparent viscosity of its solution was bigger, but their relationship was not linear. Under the same cellulose concentration, the solution viscosity increased generally in proportion to DP rising, but the solution with proportion 1:1 was one exception, and its viscosity is relatively high.
Research on Material Properties and Heat Treatment of Clamping Blocks
Authors: Chen Xu Qin , Jiang Gui Lan , Cheng Guang Zhen
Published: September 2012

This paper briefly introduces the basic component of dismantle pillar machine, respectively analyzes the structure of rotating hydraulic clamping device and fixed hydraulic device. Here mainly discussed hardenability carburizing steels 20CrNi3 that selected for clamping block, after carburizing, quenching and low-temperature tempering, obtains mechanical properties as following, intensity limit 950Mpa, yield limit 750Mpa, expanding rate 11%, section shrinkage rate 55%, impact toughness 90J.cm-2, surface hardness HRC58-63. The paper points out that the surface abrasion resistance and center impact resistance of clamping block is obviously better than surface hardening medium-carbon steel, and lamping block has a higher flexural fatigue performance. 40Cr is selected to make locating sleeve, it was quenched and tempered. The steering parts of dish-shape spring is chromalized on surface, so it can resist bending, twist and impact, its surface abrasion resistance is high and service life is long.
Experimental Study on Fire Resistant of Shield Tunnel Segment in Civil Engineering
Authors: Guo Xin Jun , Xu Zhi Sheng , Zhang Yan
Published: September 2012

Fire resistant behavior is one the main properties of shield tunnel segment in civil engineering. The main objective is to study the regularity of temperature distribution and deflection of shield tunnel segment after fire and the residual bearing capacity after cooling in this paper. According to the tests, a temperature-position fitting curve can be obtained, and it can be obtained that the damaged depth of segment is 7.8cm while heating in RABT curve for 125min. It is found that the residual bearing capacity of segment decrease with the increase of the pre-load, which drops rapidly for it is only about 20% compared to the reference one.
Exploration of the Strategies in Civil Engineering to the Safety Evaluation and Reinforcement Technique of Wood Structure of Ancient Architecture in Huizhou
Authors: Sun Qiang , He Wen
Published: September 2012

According to the field investigation of Huizhou ancient wood structure and statistical analysis of related documents, this paper expounded the main technical status and existing problems of Huizhou ancient wood structure safety evaluation and reinforcement and reconstruction, and put forward the research content of Huizhou ancient wood structure safety evaluation and reinforcement and reconstruction countermeasures, discussed the safety evaluation and reinforcement renovation the feasibility of the method for Huizhou traditional architecture reconstruction and quality improvement to provide technical reference.
Structural Design on a Building Stair by Folded Steel Plates in Civil Engineering
Authors: Li Sheng Cai , Qian Yong , Liu Yu
Published: September 2012

To ensure the safety and the logicality of a structure and to meet the needs by the architectural function and form are the main goals of a structure design. Based on the structural principles of safety, comfort and aesthetics, the mechanical characteristics, the methods of calculation and design, and the key construction technology of the stair by folded steel plates are summarized in this paper combined with the design of a steel stair in Shanghai.
Synthesis and Crystal Structure of Phosphorus Vandium Heteropolyacid Sodium
Authors: Liu Hai Xing , Xiao Jing Zhong , Wang Jing , Jian Fang Fang , Yue Hui Juan , Tai Xi Shi
Published: September 2012

phosphorus vandium heteropolyacid sodium, H78N12NaO116P2V30, is prepared by the hydrothermal method. Cubic, Fm-3m. a =b = c = 20.022(2) Å α=β=γ= 90. V=10680.0(17) Å3. Z=4. R1 =0.0388, wR2 =0.1200. T=298(2) K. The V atoms are linked with O atom bridge. The molecular structure is stabilized by the O-H...O and O-H...N intermolecular and intramolecular hydrogen-bond interaction.
Structure and Technics Research on Composite Ship T-Joint
Authors: Guo Ming En , Sun Zu Li , Yu Zhi Ning
Published: September 2012

T-joints between fiber reinforced composite material components are widely used in ship building. They are the weak positions in ship structure on mechanical properties aspect. Through experiments, the effects of structure size and technics on joint deformation and destructive strength were researched. Destructive strength first increases with the increase of T-joint fillet radius dimensions, then declines when radius dimensions over R50mm. Compared with control group, composite material components with surface sandblasting process has got superior performance, with destructive load improved by 2.1 times and displacement 1.16 times. With the increase of pressure and injection time of sandblasting process, the destructive strength of joints increases. While destructive strength increases slowly when pressure achieved 0.6 MPa and injection time achieved 100s.
Experiment Research of BDP/IFR Halogen Free Flame-Retarding for Oil-Extended SEBS
Authors: Li Yan Chun , Li Xiao Yan , Wang Xia , Han Yuan Hui , Fan Fan , Fu Zhi Yi
Published: September 2012

Bisphenol A bis (diphenyl) phosphate ester (BDP) and a kind of intumescent flame retardant (IFR) were used for flame retarding of oil-extended hydrogenated styrene-butylenes-styrene (O-SEBS). The samples were systemically characterized by TGA, LOI, UL-94, FTIR and FESEM; The results showed that, as a kind of plasticized flame retardant, BDP can improve thermal decomposition temperature and delay decomposition velocity of O-SEBS; while the IFR retardant can promote residual chars with multi-micro holes on the surface of SEBS to inhibit flame; Synergistic flame retarding effects were produced by using BDP and the IFR retardant together, with 20% BDP and 20% IFR, the LOI is 24.5 and flame retardant level is UL-94 classification of V-1, with no dripping. Meanwhile, SEBS-g-MA as compatibility can prompt char residual and thermal property of O-SEBS.
Research of the Grinding Force and Surface Morphology of Fiber-Reinforced Ceramic Matrix Composite
Authors: Wang Yu Guo , Lin Bin
Published: September 2012

Fiber-reinforced ceramic matrix composites are considered to be difficult-to-machine materials, its machining especially forming machining is very difficult. The silica fiber reinforced silica composite is studied by grinding experiment in this paper. The surface morphology of the specimens are analyzed by scanning electron microscopy, and the grinding mechanism of the composite is also analyzed. Grinding depth and feed speed is separately changed to study the grinding force. The influence of the blunt wheel on surface morphology and geometric accuracy of the specimen after grinding is explored. This research may be helpful to improve the machining quality of silica fiber reinforced silica composite.
Study on the Morphology Properties of Carbon Nanotube/Polyaniline Composites Thin Film
Authors: Ding Wen , Koutsos Vasileios , Si Jin Hai , Song Zhong Xiao
Published: September 2012

Active layer’s morphologies properties are important for the optoelectronic devices. In this paper, the morphologies properties of the carbon nanotube/polyaniline composites thin film formed by spin coating were studied by the atomic force microscopy (AFM). The results showed that spin coating way greatly affects the thin film’s topographic image, carbon nanotubes’ concentration is the key that decide whether the interpenetrating network phase separation microstructure can be formed.
A Heterojunction Film Solar Cell of Glass/ITO/CdS/PbS/Al
Authors: Wang Peng , Fan Li Bo , Sun Li Juan , Zhang Zhen Hua , Zhu Xin Bing , Zhang Yan Ge , Li Pin Jiang
Published: September 2012

A film solar cell was made with a structure of Glass/ITO/CdS/PbS/Al. CdS film was obtained by thermal evaporation. PbS film was prepared by a simple solid-solid reaction. The solar cells are photosensitive in a large spectral range (extending from near infrared to high energy side regions). The cell with the area of 0.15 cm2 without any special treatment has shown the values of open-circuit voltage (Voc) of 138 mV and short circuit current (Jsc) of 0.01 mA/cm2 with the efficiency of 0.33 % and the fill factor (FF) is 0.26 under illumination intensity of 100 mW/cm2.
Experimental Research of PCMs - TH29 Using on Building Energy Storage
Authors: Qiu Lin , Niu Run Ping , Tan Zhi
Published: September 2012

This article experimental studies the thermal Characteristics of a hydrated salt TH29 Phase change materials (PCMs),which involves phase change process and was used in building energy storage field, tests the different solid/liquid ratio of the phase change material, the whole time of phase change, and the delayed effect at different locations in phase change process, phase-changing cycles and thermal stability and TH29 temperature variety at heating and cooling modes and the delay phenomena on different location. The experimental results show that a good thermal stability of TH29 after long term phase-changing cycles can be attained under this test condition. It can satisfy people’s requirement of thermal comfort and attain function of energy saving and adjustment.
Preparation Methods of Copper-Steel Composite Wire
Authors: Wu Qing Mei , Wang De Qing , Gao Yang
Published: September 2012

The domestic and foreign preparation methods of copper-steel composite wire are introduced in the paper, they are basically plating method, hot-dip plating method, continuous extrusion method, clad-welding method and hot extrusion welding method. The advantages and disadvantages of these methods are compared and analyzed. Among of them, hot extrusion welding method is a common method in foreign for producing copper clad steel wire. In recent years, the equipment and the technology are introduced by domestic companies and put it into production, it fills up the gap for producing copper clad steel wire in the domestic and it provides new market and application prospects for copper clad steel wire produced and applied in the domestic.
Effect of Wheel Speeds on the Microstructure and Magnetic Properties of Melt-Spun (Nd0.75,Dy0.25)10.5 Zr2Fe82B5.5 Ribbons
Authors: Qiu Jie , Li Shan Dong , Liu Mei Mei , Wu Jian Peng , Hu Yi , Cai Xin Le , Lin Jian Hua , Wang Li Li
Published: September 2012

Nanocomposite (Nd,Dy)2Fe14B/α-Fe magnets were prepared by directly solidification (DS). The effect of wheel speed on the magnetic properties, microstructure and exchange coupling interaction has been studied. It was found that a uniform R2Fe14B/α-Fe nanocomposite structure with fine α-Fe grains can be developed at an optimum wheel speed of about 18 m/s. Without any heat treatment, the optimal ribbons (v = 18 m/s) show a strong exchange coupling interaction and good magnetic properties, e.g. iHc=1027 kA/m, mr =0.71, (BH)max=174 kJ/m3.
High-Speed Railway PFV Prediction Model Research Under Regional Economic Conditions
Authors: Du Xue Dong , Ren Na
Published: September 2012

Under the regional economic conditions, a passenger flow prediction model is proposed in the paper. It can predict high-speed railway passenger flow volume under the conditions of multi-mode, and guide the reasonable operation of high-speed railway effectively. According to the data analysis of Beijing and Tianjin railway stations, we can know that the reasonable ticket price plays an important role in high-speed railway operation benefit under regional economic conditions.
Research on Oxygen Content and Crack Control of Oxygen-Free Copper Billet in Horizontal Continuous Casting Process
Authors: Guo Ming En , Shi Yun Xu , Guo Yu Chen
Published: September 2012

In this paper, research on reducing oxygen content and crack in oxygen-free copper strip during horizontal continuous casting process has been taken. First, reform the original copper alloy smelting-holding-casting three stages process. Through developing melting and holding integrative furnace, combine melting process and holding process for one, reforming smelting holding-casting two stages process. Second, pick up and realize on-off valve technics on controlling flow or stop of undercurrents copper liquid. Third, analyze the cracks in oxygen-free copper billet with flakinessratio 6500/20mm. And finally determine reasonable cooling process parameters through experiments. The results shows when oxygen content ≤0.0004% and density rise to 8.94-8.95 g/cm3, the crack has been completely eliminated.
Manufacturing Process Design of Multi-Scale Synthetic Leaves Based on Microcapillary Plastic Film
Authors: Xu Zhong Bin , Wang Bai Cun , Cao Jia Pei , Liu Yu
Published: September 2012

In order to develop the new environment-friendly synthetic leaves, the concept of synthetic leaves based on microcapillary plastic film (MCF) is proposed according to the existing MCF process. The manufacturing scheme of multi-scale synthetic leaves based on MCF is designed below: (1) development of new dynamic MCF extrusion technology, (2) manufacturing of synthetic leaves with controlled dynamic microcapillary and multi-scale microstructure using the supercritical fluid foaming and the excimer laser drilling technology, (3) functional bionic of the leaf transpiration. The feasibility of the above-mentioned scheme is proved with the carried-out experiments. The successful development of the MCF synthetic leaves will not only provide a new way to solve the desertification problem, but also to promote advancement of many fields such as micro-structure plastic processing, plant physiology ecology, bionics and micro fluidic system.
The Simulation of CO2 Recovery & Liquefaction Flowsheet in the Beer Fermentation Process by Aspen Plus Software
Authors: Yu Ke Zhi , Tang Jia Xiong , Ling Xiang
Published: September 2012

Aspen Plus software is adopted to simulate the CO2 recovery & liquefaction flowsheet in the beer fermentation process. The foam trap, balloon and CO2 storage tank are removed from the simulation objects so as to simplify the simulation, and other devices adopt corresponding module and property method to ensure the simulation accuracy. The Comparisons show that the simulation results are agreement with the measurements, which means the flowsheet simulation is successful.
The Study of the Plastic Cover Mold Design and Process Optimization Based on Moldflow
Authors: Yang Dong Po , Han Jian Min
Published: September 2012

In this paper, according to the quality problems of the plastic cover such as the difficulty control of the mold temperature, long cooling time, low production efficiency and deformation, it analyses the problems existing in the mold causes and find solutions based on Moldflow as a research tool. By improving the quality of gate position to control the filling quality, redesigning the cooling system to improve cooling efficiency, optimizing molding process to control product quality and increasing wall thickness to eliminate air traps and weld lines guide the design and manufacturing of the new mould. It establishes the gating system and cooling system based on the ASA778T as filling material and the analysis of simplified model. Select the process: the mold surface temperature is 80°C, the melt temperature is 240°C, the mold-open time is 15s, the packing time is 10s, the packing pressure is 80Mpa, injection+packing+cooling time is 45s. This process reduces the molding cycle from 65s to 42s, decreases the maximum deformation in 2.866mm, ensures the product quality, saves the cost and improves the production efficiency.
Synthesis and Investigation of Al2O3/SiO2 /ZrO2 Powders via Selective Laser Sintering
Authors: Wang Wei , Liu Yong Xian , Shi Xiang Dong , Li Jin Hua , Fuh J.Y.H.
Published: September 2012

This research focused on the synthesis and investigation of the thermal properties and microstructure of the Al2O3/SiO2 /ZrO2 system applied to dental field. The composite ceramic was studied by scanning electron microcopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Detailed investigations of the different proportions of materials on the preparation and microstructural phases of ternary eutectic were presented. Furthermore, the crystallization process was investigated by using DSC and XRD. The results indicate that sintering microstructure of the ternary eutectic composite is greatly influenced by the materials proportions. The synthetically thermal analysis shows that the eutectic temperature of ternary Al2O3/SiO2 /ZrO2 composite is 1040°C, is well matching the phase diagram of Al2O3/SiO2 /ZrO2.
A Review of Flow Pattern of Boiling Flowing in the Tube
Authors: Zhang Jun Xia , Nuoribusiren N.
Published: September 2012

Both boiling flowing and heat transfer has widely applied to engineering. The predictions of boiling heat transfer depend on the characteristics of boiling flow pattern, and thus it is necessary to comprehend the update development of flow pattern of boiling heat transfer. At the present work, the recent investigations were reviewed, and these findings mainly focus on the classification of various flow patterns and the transition of flow pattern. The obtained flow pattern map is mainly based on the experimental data from air-water at adiabatic conditions. These investigations tend to propose a simple and general flow pattern map; however, the limitation of both experimental conditions and the number of experimental data modifies the goal. Analysis of flow pattern transition has been developed from few semi-empirical and semi-theoretical models; its application has been limited because of complexity of flow pattern and many determinant factors.
Study on Short-Circuit Transition Welding System Based on Push-Pull Wire Feeder
Authors: Huang Peng Fei , Wang Chang Wu , Lu Zhen Yang , Bai Li Lai
Published: September 2012

A welding system based on a push- pull wire feeder was designed and how it works was analyzed. The system included the welding power supply, the wire feeding system, and the coordination controller. The power supply used a current mode PWM IC UC3846 as the controller, which made sure the security and the dynamitic responsibility of the system. The critical fact to realize the push-pull wire feeding system was that a small inertia and fast response AC servo motor was selected. TMS320F2808 was used as the core coordination controller of the system, which made the welding power source and the wire feeding system work coordinately. The motor will pull the wire back when the arc was in the period of short-circuiting, and push the wire forward when the arc was in arc period. The results proved the system can meet the welding demands.
A Study of Engineering Construction Safety Influencing Factors Based on SEM Model
Authors: Zhou Jian Lan , Sun Zhi Yu
Published: September 2012

During the long engineering project construction period, involving a combination of human, financial and material, and that different works, every link and each phase is mostly high altitude, open, crossover operation, which hide safety risks and result in high probability of safety accidents, so these characteristics determine the importance of safe and civilized production. Therefore, the influence factors of engineering construction safety are worth studying. In this paper, through extensive reading literature and information, making contrast and analyzing, researching and other methods, finishing the preliminary indicators of construction safety influencing factors, after conducting questionnaire survey, ultimately identified 19 indicators of factors and based on these indicators draw SEM model by AMOS software. The results by AMOS show that the model can effectively describe the relationship between the influence factors of which affecting construction safety, and provide strong evidence for improving the engineering and construction management.
Based on the Finite Element Method for Gear and Rack Research on Contact Fatigue Strength of Study
Authors: Li Yong Xiang , Yang Lei , Wang Ming Xu , Wang Zhen
Published: September 2012

The paper summarizes gear experimental method of contract fatigue strength and the current status in domestic and overseas analyzes the experimental current situation, existing problems and the development trend; introduces the applications of finite element analysis used in contact fatigue strength calculation. On this basis, has given the finite element analysis method in the solution gear rack contact fatigue strength testing research measure and the mentality.
Dynamic Simulation Analysis of Shipborne Missile Launching under High-Wave-Level Environment
Authors: Zhong Zhou , Jiang Yi , Li Yong Yuan , Zhang Chong
Published: September 2012

In order to study the dynamic response of shipborne missile vertical launching under high-wave-level environment, the rigid-flexible coupling dynamic model of launching system was built by ways of virtual prototype technology. According to simulations for different launching conditions, missile attitude parameters were acquired, and interference of various parts was analyzed. The result shows that the dynamic model and simulation method proposed in this paper are effective and practicable.
The Optical Properties of Au/Ag Nanoparticles Coated with Diamond-Like Carbon Films
Authors: Ma Nan Yu , Huang Yu Jie , Li Mu Sen
Published: September 2012

Abstract. Noble metal nanoparticles have prominent surface effect, quantum size effect and active outer-shell electrons, they cause these particles to present unusual optical phenomenon, display the strong local surface plasma resonance (LSPR) effect. DLC films have good biological compatibility, good wear resistance and corrosion-resisting, it also has high transmissibility in the visible and near-infrared region. A new LSPR interface between diamond-like carbon films and the Au/Ag NPs was formed by Plasma Enhanced Chemical Vapor Deposition (PECVD), The optical and electrical properties of the samples were studied with ultraviolet-visible absorption spectrophotometer and Raman spectrometer. The results indicate that their transmittance decreased with the increase of the film thickness.
Numerical Simulation Study on High-Temperature Ventilated Cavitating Flow Considering the Compressibility of Gases
Authors: Zhao Jing , Wang Guo Yu , Zhao Yan , Liu Yue Ju
Published: September 2012

A numerical simulation approach of ventilated cavity considering the compressibility of gases is established in this paper, introducing the gas state equation into the calculation of ventilated supercavitating flow. Based on the comparison of computing results and experimental data, we analyzes the differences between ventilated cavitating flow fields with and without considered the compressibility of gases. The effect of ventilation on the ventilated supercavitating flow field structure is discussed considering the compressibility of gases. The results show that the simulation data of cavity form and resistance, which takes the compressibility of gases into account, accord well with the experimental ones. With the raising of ventilation temperature, the gas fraction in the front cavity and the gas velocity in the cavity increase, and the cavity becomes flat. The resistance becomes lower at high ventilation temperature, but its fluctuation range becomes larger than that at low temperature.
Study on Fatigue Life of Pressure Vessels Based on Random Load
Authors: Hu Guang Zhong , Liu Zhong Bin , Kang Liu , Wang Tao Quan
Published: September 2012

The paper discusses the fatigue design theory of pressure vessels. For pressure vessel loads absorbed (pressure, temperature, earthquake, wind, snow, etc.) have significant stochastic dynamic characteristics and coupling characteristics, fatigue life analysis of pressure vessels based on random load history is proposed. Discusses in detail the random load spectrum rain flow counting process, the linear damage theory and fatigue life analysis. The new structure reactor of synthesis system fatigue life is calculated, the results show that the fatigue life and the design life of equipment vary widely, the need to improve pressure fluctuations of the synthesis of system.
Stability Analysis of Biped Walking
Authors: Zhou Xue Feng , Huang Peng , Zhang Gong , Chen Xian Shuai
Published: September 2012

Tipping-over and slipping, which are related to zero moment point (ZMP) and frictional constraint respectively, are the most two common instability forms of biped robotic walking. Conventional criterion of stability is not sufficient in some cases, since it neglects frictional constraint or considers only translational friction. The goal of this article is to fully address frictional constraints in biped walking and develop corresponding stability criteria. Frictional constraints for biped locomotion are first analyzed and the method to obtain the closed-form solutions of the frictional force and moment for a biped robot with rectangular or circular feet is then presented. The maximum frictional force and moment are calculated in the case of ZMP at the center of contact area. Experiments are conducted to verify the effectiveness of our stability analysis.
Theoretical and Experimental Study on Stiffness Characteristics of a Wire Race Ball Bearing
Authors: Zhong De Fu , Yuan Jiang Bo , Shan Xiao Biao , Xie Tao
Published: September 2012

A new mathematical model on the stiffness matrix of the bearing was established by using the non-conforming Hertz contact theory. In this model, the case of compound load and the coupling effects was considered. The numerical arithmetic to estimate the displacements under the compound loads is discussed. As a sample, a wire race ball bearing used in a certain type of three-axis aircraft simulating rotary table was provided. The curves of axial stiffness and radial stiffness were obtained in MATLAB. The experimental system for measuring the stiffness was built. The experimental results verify the validity of the theoretical model.
RMRS: A Reconfigurable Modular Robot System and its Applications
Authors: Zhou Xue Feng , Jiang Li , Cai Chuan Wu , Zhu Hai Fei
Published: September 2012

Modules have been widely used in development of various robots including reconfigurable robots. To build robots flexibly and quickly with low costs, we have developed two basic joint modules and several functional modules including grippers, suckers and wheels/feet as end-effectors. In this paper, we introduce the development of these modules, and present several novel robots built using them. Specifically, we show how to use them to set up a manipulator, a 6-DoF biped walking robot, a wheeled mobile robot, a biped tree-climbing robot, and a biped wall-climbing robot. It has been shown that a few modules can easily spawn a variety of novel robots with modular methodology.
Pipeline Frequency Test Bed Design
Authors: Wang Jie , He Yu Min
Published: September 2012

For the production of high reliability, wide use range, low cost of pipeline frequency test rig, the design scheme is determined, the structural design. Design of experiment platform to meet the requirement of experiment, and has practical application value.
Simulation for Pole Placement in Textile Machinery Electrohydraulic Servo System
Authors: Xu Jun Yan
Published: September 2012

The observer for reflecting the system state parameter has been designed according to the stability and accuracy requirement of electrohydraulic servo system. With pole placement done by the observer, it greatly improves the system performance compared with the widely used output feedback adjustment control method.
Finite Element Analysis of a Mechanical Heart Valve in Assembly
Authors: Wu Liang Liang , Wan Guo Jiang , Zhou Feng , Yang Jie , Huang Nan
Published: September 2012

The Bileaflet Mechanical Heart Valve (BMHV) has been the most successful replacement mechanical heart valve, and is currently the most commonly implanted mechanical valve. Although the BMHV is an improvement over previous mechanical heart valves, there are still serious associated complications with its use that must be eliminated. After the completion of the processing and surface modification, heart valve ring and heart valve leaflets constitute a single whole with mechanical method to achieve its function process. In order to ensure that the heart valve is stable and reliable in service, it is particularly important to improve the assembly quality. The theoretical analysis and simulation used of ANSYS Workbench software for the behavior of the heart valve assembly have been done, the experimental results were verified by testing apparatus, which is a helpful tool used to simulate the new structure of the heart valve assembly, and play a certain significance to improve the accuracy of the assembly.
Finite Element Analysis on the Vibration Mode of Composite Thin-Walled Box Beam with Double-Cell Sections
Authors: Sun Shuang Shuang , Jia Fang Wu , Ren Yong Sheng
Published: September 2012

The modal analysis of composite thin-walled box beams with double-cell sections is carried out by the finite element software ANSYS. The finite element models are established first for the double-cell composite thin-walled box beams, then the vibration modes of two box beams: Circumferentially Uniform Stiffness (CUS) and Circumferentially Antisymmetric Stiffness (CAS) are calculated and analyzed. The effects of length-width ratio and width-height ratio on the natural frequency and the modal shape of the double-cell composite thin-walled box beams are discussed.
Research on Mining Method of Submarine Natural Gas Hydrates Based on a Double-Channel Lift Pump
Authors: Zeng Yi Cong , Xu Hai Liang , Wu Wan Rong , Wu Bo
Published: September 2012

Based on the geological characteristics of the submarine natural gas hydrates storage and the requirement of the mining environment, combined with the deep sea mining technology and the main characteristics of the double-channel lift pump, a new mining method called the mining method of submarine natural gas hydrates based on a double-channel lift pump is proposed in this paper , whose operating principle is that the hydrates are firstly cut into particles and extracted by a spiral reamer of a mining vehicle, next hoisted by a double-channel lift pump to the decomposing pool on the surface, and then decomposed and collected. After the mining method has been introduced, the hydraulic hoisting system parameters such as the pump head of the double-channel lift pump and the hoisting system parameters are analyzed. From calculation and analysis, it is obtained that the gas hydrate particles at the depth of 4000m pumped up to the sea surface require the pump head only 145 m and the working power only 236kw,which can be easily implemented by the existing technology, and the hydrates at the depth of 1000 pumped up to the sea surface just require the pump head about 50 and the working power about 80 kw, which the existing double-channel slurry pump can meet the requirements. Because the density of the mixture flow of the gas hydrates, the seafloor surface sediments and the seawater is similar to the seawater, the transportation mode that the hydrates are transported as ore slurries directly can ensure that the hoisting system keep working steadily and reliably for a long time. It is proved theoretically that the mining method is suited to exploit the submarine natural gas hydrates.
Numerical Simulation of Burner for Micro Gas Turbine
Authors: Jia Lei , Liu Shi , Huang Yao Song , Wang Neng , Wang Fu Zhen , Li Zhi Hong
Published: September 2012

In order to study affects of oxy fuel combustion on micro gas turbine ,three axial swirl burners with different installation angles for micro gas turbine were designed, flue gas recycle/oxy fuel was used to burn natural gas. Numerical simulation was used to study flow field and combustion conditions. The result shows that application of axial swirl burner promotes mixing process of natural gas and oxygen and recirculation brought about to promote the stability of fire, uniformity of outlet temperature was reduced. With the increase of swirl installation angle, backflow becomes more intense, and uniformity of outlet temperature becomes smaller, however, total pressure loss coefficient increased. These results will have a great significance in the design of better burners.
The Analysis and Experimental Verification of the Hump Characteristic of Viscous Couple
Authors: Jin Li Qiang , Song Chuan Xue , Song Shi Xin
Published: September 2012

During working, the speed difference between the driving and driven plate of the viscous couple will generate heat and increase the temperature of the silicon oil, inflate the volume, increase the pressure, and eventually deliver more torque. This phenomenon is called the hump characteristic. In this paper, the cause of the hump characteristic will be discussed. By analyzing the characteristic of ideal gas, the variation characteristic in internal pressure is obtained. A viscous limited slip differential is development to test the hump characteristics and to get the peak value occurrence time and the delivering torque.
TRIZ Based Tool Management Applied in Mechanical Heart Valve Engineering Systems
Authors: Zhou Feng , Cui Yuan Yuan , Wu Liang Liang , Chen Yin , Yang Jie , Huang Nan
Published: September 2012

Artificial mechanical heart valve (MHV) replacement is the common cardiovascular surgical procedure, yet its effect is far from satisfaction. Most important reasons lie in the model design and choice of the materials in the fabrication of the prosthetic heart valves. Based on systematic design methodology of TRIZ theory (Russian acronym for Theory of Solving Inventive Problem), the device structure is analyzed by comparing the past successful designs generated during the evolution of MHV. This paper represents a modeling technique integrating the well-established TRIZ with the conflict and contradiction modeling, substance-field and product functional analysis tools and provides some important trends in evolutionary development of production systems in MHV design. By analyzing the structural behavior and material performance, a complex case study from the research of different structural patterns and characteristics of current tri-leaflet modeling shows the validity of TRIZ theory to guide MHV design.
The Analysis of Electric Vehicle Ride Comfort Test Simulation Based on the Adams/Car
Authors: Fan Xin , Hu Chun
Published: September 2012

According to the national standard on electric vehicle model, pulse input test and random input test were conducted. The results show that: at different speeds through the triangular bump, its maximum acceleration is far less than 31.44m2/s, there is no harm to the driver's health; random input road ride comfort simulation trials has similar results, with the improving speed, the acceleration rms value of the driver's seat increases, but the driver will not feel uncomfortable. In addition, it was analyzed the influence of front and rear suspension spring stiffness and vibration-damper damping on the vehicle ride comfort, and increasing or decreasing of each parameter affect the trend on the vehicle's ride comfort.
Prediction Behavior of Notched Composite under Compression Force with Experimental Method
Authors: Norazar S.S. , Pazand Kamran , Oskoei A. Refahi
Published: September 2012

Buckling is a geometric instability and is related to material stiffness, column length, and the cross-sectional dimensions of the column. Strength does not play a role in buckling. Buckling is not specific to composite materials, but some factors could promote buckling. This paper predicts the fast determination of displacement distribution and force in composite under force of bucking. For these purpose Experimental models of notched and without notched composite plate are developed under dynamic axial force with clamped boundary condition to investigate force - displacement behavior in different plies in composite. The resulting data would then be used to train artificial neural networks (ANN) which would be able to predict those quantities throughout the composite plate body for any given input value in any position ply and force and displacement that impose.
Late-Stage Evolution of Thin Liquid Coating Films over Step Topographies
Authors: Asgari Mehdi , Moosavi Ali
Published: September 2012

Mesoscopic hydrodynamic equations are solved to investigate late-stage evolution of thin liquid films over step topographies. Different geometrical parameters including step height and initial position and configuration of resultant masses of dewetting (droplets) are probed to find their effects on the mass evolution of the system. Our results indicate that increasing the step height and locating the droplets close to the step enhance the dynamics and accelerate smaller droplet collapse.
A Design Technique for a Magnetic Bearing-Rotor in a Turbo Blower Considering Critical Speeds
Authors: Jung Hoon Hyung , Kang Seung Hee , Cho Bang Hyun , Kim Chae Sil
Published: September 2012

This paper introduces a rotor design technique for a turbo blower supported by magnetic bearings that considers the critical speeds of the rotor. An important factor for rotor critical speeds is the stiffness of its bearings. The magnetic bearing acts as a negative spring, called the position stiffness prior to operation, and rotor systems are initially unstable until the stiffness (current stiffness) and damping in the active control rotating system are determined using closed loop control forces. This paper describes a finite element model for the rotor, derives the stiffness equations for the magnetic bearing, and defines the total magnetic bearing stiffness including the position stiffness and current stiffness. Finally, the magnetic bearing stiffness that avoids the rotor critical speeds is chosen.
Dynamic Modeling and Analysis of Astronauts’ Exercise during Spaceflight
Authors: Chen Hao , Li Dong Xu
Published: September 2012

Astronauts’ exercise during spaceflight will bring low-frequency disturbance to the spacecraft. In order to analyze the corresponding dynamic effects on the spacecraft, an astronaut-cycle ergometer-spacecraft system is taken as an example. The dynamic model is established in this paper. The topological structure of the astronaut-cycle ergometer-spacecraft system is given and equalized to an open tree system. Utilizing recursive relation of displacement and velocity between connected units, equations of motion of the system are reduced to the spacecraft. Simulation implies astronauts’ exercise will result in rotational drift of the spacecraft. Meanwhile, the microgravity environment is heavily destroyed. Compare with traditional modeling method, our method is more accurate as it considers dynamic coupling effects. The simulation results can be considered as a reference to the control system and it also reveal changes of microgravity environment.
Research on Settlement Characteristics of Storage Tank Group on Non-Composite Foundation
Authors: Wang Shuai , Yu Ran Gang , Zhang Yan Mei , Wang Xiao Xue
Published: September 2012

This paper analyzes the settlement of storage tank group and the settlement characteristics with different loading methods. The result shows that the deformation of storage tank foundation is a tilted ‘hat’ in shape under the influence of group effect ,and different loading methods obviously influence the degree of plane tilt and non-plane tilt of tank foundation.
Singularity Analysis of 2-DOF Parallel Manipulator
Authors: Lee Jong Gyu , Lee Sang Ryong , Lee Choon Young , Yang Seung Han
Published: September 2012

The end-effector of 2-DOF parallel manipulator has an orientation. Jacobian matrices are obtained by kinematic analysis. The singular configurations of the manipulator are found using these matrices and the certain characteristic of these configurations is investigated. With the result from simulation, we found that these configurations happened to workspace-interior as well as workspace-boundary and the orientation angle of the end-effector exerted a strong influence on the singularity of the manipulator.
Lightweight Design for a Cab of a Heavy-Duty Truck Based on Passive Safety
Authors: Wang Xin Yu , Wang Deng Feng , Sun Wan Lai , Liu Pei Wu
Published: September 2012

This paper focuses on the cab of a heavy-duty truck. Lightweight design and structural improvements for the cab-in-white were carried out by using the topology optimization shape optimization and size optimization methods, and the weight was reduced by 46kg without changing the cab structural materials. Performed modal analysis of the lightweight cab, and then compared analysis results with those corresponding results of the original cab. Comparative analysis showed that the first ten natural vibration frequencies of the lightweight cab all have a certain increase compared with those of the original structure. On this basis the simulation analysis of the passive safety of the lightweight cab was performed. Besides a sample of the lightweight cab was developed, and tests on the passive safety of the lightweight cab were completed. Tests results validated that the passive safety of the lightweight cab met the requirements of ECE R29. Also the effectiveness of the cab structural lightweight design improvements and the simulation analysis of the passive safety was verified by tests.
Analytical Techniques of Case and Pad for 5-Pad Tilting Pad Bearing
Authors: Shin Min Jae , Hwang Jae Duk , Kim Chae Sil , Cho Soo Yong
Published: September 2012

As the pad of a tilting pad bearing has invisible, three dimensional complicated movements around its pivot point inside the bearing case, its contact surface is difficult to establish. The loading points inside the bearing case are also not easy to predict accurately. This paper presents practical analysis techniques and loading conditions for the pad and bearing case of a tilting pad bearing in the structural analysis to meet the actual operating conditions. The analysis for the pad is conducted by applying the pressure of lubricant to the whole pad surface and constraining the circumferential degrees of freedom at nodes around the pivot. Part of the pad of boundary condition is hydraulic of practically applied lubricant and contact area of pivot and the rotational degree of freedom in line with circumferential. It is proposed to using of external case boundary condition 4 pads and 5 pads. Points of the case, combined with the pad are applied to the actual load. The result of analysis, the reliability of the pad and the case was obtained, because stress distribution is nearly identical with the actual phenomenon.