bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of HPC on the Thermo-Sensitive and Hydrophilicity of PAN Films
Authors: Gong Guo Li , Li Hui
Published: July 2011

In this paper, a series of blending films were prepared based on Polyacrylonitrile (PAN) and hydroxypropylcellulose (HPC). The phase transition temperature of these blend films was investigated by warming UV-vis spectrophotometer and Differential Thermal Scanning Calorimetry (DSC). The results showed that the phase transition temperature of HPC/PAN blend films was lower than that of HPC when adding PAN into HPC and the more PAN contents the lower LCST of blend films. The contact angle and surface image of HPC/APN blend films were studied. It was indicated that HPC could endow PAN film with not only thermo-sensitive property but also great hydrophilicity.
Polymer Electrolyte of PVDF-HFP/PEMA-NH4CF3So3-TiO2 and its Application in Proton Batteries
Authors: Rudhziah Siti , Ibrahim Salmiah , Nor Sabirin Mohamed
Published: July 2011

In this study, composite polymer electrolytes were prepared by addition of titanium oxide, TiO2 nanofiller into polyvinylidene fluoride-co-hexafluoropropylene/polymethyl methacrylate-ammonium triflate (PVDF-HFP/PEMA-NH4CF3SO3) complex. The effect of TiO2 on conductivity of the complex was examined using impedance spectroscopy. The highest room temperature conductivity of 1.32 × 10-3 S cm-1 was shown by the system containing 5 wt % of TiO2. This system was used for the fabrication of proton batteries with the configurations of (Zn + ZnSO4.7H2O + C + PTFE)/PVDF-HFP/PEMA-NH4CF3SO3-(5wt%)TiO2/(MnO2 + C + PTFE) and (Zn + ZnSO4.7H2O + C + PTFE)/PVDF-HFP/PEMA-NH4CF3SO3-(5wt%)TiO2/(MnO2 + PbO2 + C + PTFE). The performance of the batteries indicated potential application of the electrolyte system in proton batteries.
The Modeling Design and Research of Multi-Function Electric Fan
Authors: Jiang Xiao Wei
Published: July 2011

The article is inspired by the exterior shape of the electric fan, which analyzed the extensive developing design space of it. And it also combined the design problem of the existing electric fan in the art function and using function. A multi-function electric fan which simulated the shape of Beijing Olympic auspicious cloud torch has been designed. It discusses the design purpose, the requirements of the electric fan, the designing process, the function design and form design, and the function design is mainly describe the operating principle and a variety of using function. The multi -function including the basic function of the electric fan and the air moistening function, automatic temperature measurement function, automatic ventilation control function, automatic time display function, fire alarm function and music function etc. While shape design pointed out the artistic quality, man-machine quality and analyzed its feasibility. On that basis, it made a conclusion.
Development of Intelligent Drilling and Intelligent Drill Tools
Authors: Yu Rong Hua , Yuan Peng Bin
Published: July 2011

This paper introduces the principles and techniques of intelligent drilling which can be considered as a computer intelligent expert system with intelligent drill tools and information network system as the key technologies. In this paper, we have discussed the key technology of how to combine power transmission and high speed bidirectional information transmission “information superhighway” with drill tools, and also have introduced the design and development of intelligent drill tools specifically which Hilong company who possesses the independent intellectual property rights.
Finite-Element Analysis of the Arm Lock of Ejection Seat Interlock Device
Authors: Xu Ying , Yang Jun Hu , Hou Bing Duo , Peng Lang Cao
Published: July 2011

Analysis of the causes about the ejection seat in the ejection process, when the aircraft canopy is not throw away , ejection mechanism ignites advance. using the finite element method(FEM) to carry on the deformation analysis of the lock arm in the interlock device, defined the strength of the lowest parts of the lock arm, obtained the stress distribution graph of lock arm, which provides a theoretical reference for the interlock device on the optimal design.
Summary on On-Line Balancing Techniques and Devices of Spindle
Authors: Bai Cai Bo , Teng Peng Fei , Ma Rui , Sun Chang Jing
Published: July 2011

This paper summarized various adopted widely balancing technology of spindle, specially introduced the principles, structural characteristics, advantages and disadvantages, research and application situations of several on-line balancing devices. Finally, Aiming at the existing problems in the applications of the technologies in spindle dynamic balancing, the article points out the directions in the applications of on-line balance of spindle, and some key problems to be solved in future.
Effect of Magnetic Fields on the Resistance and Microstructure of Al-Cu Alloy during Solidification Processing
Authors: Ban Chun Yan , Qian Peng , Zhang Xu , Ba Qi Xian , Cui Jian Zhong
Published: July 2011

The resistance of Al-21%Cu alloy under no magnetic field, DC magnetic field and AC magnetic field from liquid to solid was measured by a four-probe method. The difference of resistance versus temperature curves (R-T curves) was analyzed. It is found that the R-T curves of Al-21%Cu alloy are monotone decreasing and have two obvious turning points. Under DC magnetic field, the liquidus and solidus temperatures of the alloy both decrease, while under AC magnetic field, the liquidus and solidus temperatures both increase. There is a good agreement between the microstructure of quenching sample and R-T curves. The mechanism of the effect of magnetic fields was discussed.
Chemical Reaction Mechanism of Sintering Flue Gas Desulphurization with Pyrolusite Slurry
Authors: Gui Yong Liang , Yan Qi Cao , Yan Ya Kun , Song Chun Yan
Published: July 2011

With the beginning of the characteristics of sintering flue gas, the thermodynamics and chemical reaction mechanism of sintering flue gas desulphurization with pyrolusite slurry were analyzed and discussed in the paper. Results shown that the main chemical reaction was oxidation-reduction reaction of sulfur dioxide and manganese dioxide with a high reaction velocity and desulphurization efficiency at the first stage. The reaction speed and the desulphurization efficiency decreased gradually and Mn2+ is used as catalyst in the desulphurization reaction with the proceeding of chemical reaction and decreasing of PH value of solution.
Study on Behavior of Impurity Antimony in Zinc Electrowinning
Authors: Yu Xiao Hua , Li Yong Gang , Xie Gang , Lu Ying , Ji Kun Wang , Shi Zhe
Published: July 2011

By means of an electrochemical study, the influence of Sb3+ on cathode polarization process in zinc electrowinning and its kinetics equation and parameters have been studied. The results show that antimony has a depolarization function in the presence of [Sb3+] ≥0.5 mg·L–1 in zinc electrowinning, and Sb3+ has a polarization function in zinc electrowinning in the presence of [Sb3+] ≥1 mg·L–1, the polarization curve enters into the hydrogen evolution range from the activation range, which indicates that the presence of antimony has adverse influence on the zinc electrowinning process.
Improve the Charge Balance of White Phosphorescent Organic Light Emitting Diodes Using Co-Doped Electron Transport Layer in Emitting Layer
Authors: Tsai Yu Sheng , Hong Lin Ann , Juang Fuh Shyang , Lai Kuang Chih , Lai Chang Jun , Ye Guan Hong , Yeh Pei Hsun
Published: July 2011

White phosphorescent organic light-emitting diodes (WPHOLED) with high efficiency and low driving voltage were achieved by incorporating an electron transport material (3TPYMB) into a hole transport-type host (TCTA) as a mixed-host structure. For electrons, the emitting layer is nearly barrier-free until they reach the region of exciton formation, which keeps the driving voltage low. Therefore, improved the charge carrier balance within the emitting layer and enhanced the power efficiency of device. White PHOLED at a luminance of 1000 cd/m2 shown a driving voltage of 4.38 V, luminance efficiency of 36.1 cd/A, and power efficiency of 26.4 lm/W was observed. Furthermore, the power efficiency can be improved to 34.27 lm/W, and luminance efficiency to 46.7 cd/A by attaching a brightness enhancement film (BEF).
Research on Trivalent Chromium Removal from Wastewater by Gas Quenching Steel Slag
Authors: Li Jun Guo , Wei Ling Hong , Zhang Yu Zhu
Published: July 2011

Gas quenching steel slag (GQSS), which was prepared by gas quenching equipment under inert atmosphere, possessed some advantages for pollutants removal from wastewater. Static state experiment has been carried on to investigate Cr(III) removal from wastewater by GQSS. The results indicated that solid-liquid ratio, Cr(VI) original concentration, libration time and dissolved oxygen have significant influence on Cr(III) removal percentage. Take economic cost into account, the ratio between the mass of GQSS and the volume of Cr(III)-bearing solution should be controlled at 3:100. Because Cr(III) removal from wastewater by GQSS went through absorption and precipitation, the removal percentage of Cr(III) increased gradually with the reaction time. Moreover, Cr(III) removal percentage declined with the increasing of Cr(III) original concentration. Along with the declining of dissolved oxygen under sealed with lid, the redox potential in the solution decreased, and then the removal percentage of Cr(III) increased.
Research on Internal Stress in Electroplated Cu Films and Ni Films on Ag Substrates
Authors: Zhu Yao Min , Wang Shan Shan , Ren Feng Zhang
Published: July 2011

Electroplating was employed to prepare Cu films and Ni films on Ag substrates. The average internal stresses in Cu film and Ni film were measured in situ by cantilever beam test. The values of experimental internal stresses were compared with theoretical internal stresses. The results showed that the internal stresses of Cu film and Ni film decreased with the increase of the film thickness. The reduced gradient was faster. The values of experimental and theoretical internal stresses had the same variation trend with film thickness and the same characteristics (tensile stress). Theoretical calculation model of internal stress was of accuracy. The internal stress for the same substrate was in relation to the film material.
Position and Anti-Swing Control Based on BVP Arithmetic for Bridge Cranes
Authors: Yu Zhan Dong , Xu Jiang Tao , Wang Xian Feng
Published: July 2011

The anti-swing problem of the bridge cranes is discussed. The position and anti-swing control strategy based on BVP arithmetic is presented. The position and anti-swing control programming of bridge cranes can be transformed into the two-point boundary value problem (BVP) of nonlinear systems. According to the boundary conditions, the tractive force function of Fourier series form with free parameters is constructed. The BVP is solved with the bvp4c function in Matlab toolbox, and the tractive force sequence is obtained. The presented position and anti-swing control strategy for bridge cranes belongs to open-loop feedforward control essentially. The simulation of anti-swing and position control process illustrates the effectivity of the control strategy.
Mathematical Model of Dynamic Recrystallization of U75V, RE-ⅡHeavy Rails
Authors: Bao Xi Rong , Chen Lin , Guo Ya Peng
Published: July 2011

The effect of deformation conditions on dynamic recrystallization of U75V、RE-Ⅱwas studied by high temperature compression tests on Gleeble-1500D thermomechanical simulator. The models of activation energy Q and dynamic recrystallization were obtained by linear regression method to provide basic data for prediction and control of microstructure and properties of U75V、RE-Ⅱproducts.
Infrared Light Absorption and Emissivity of Silicon Microstructured by Femtosecond Laser in SF6
Authors: Li Yuan , Feng Guo Jin , Zhao Li
Published: July 2011

The surface microstructured silicon prepared by femtosecond laser pulses irradiation in SF6 shows significantly enhanced light absorption over a wide wavelength range. Absorptance of microstructured silicon is measured from 2 to 16μm, and the absorptance can up to 0.8 in the measured wavelength range. The absorptance of microstructured silicon increases as the height of spikes increases. Emissivity of microstructured silicon at different temperatures(100°C-400°C) is measured from 2.5μm to 25μm. Greatly enhanced emissivity compared to that of flat silicon was observed. At a certain temperature, with increasing the height of the spikes, the emissivity increases. For a sample with 13–14μm high spikes, the emissivity at a temperature of 100°C is approximately 0.96. A tentative explanation for the high absorptance of microstructured silicon has been carried out from three aspects: impurity states, structure defects and multiple reflection of light between spikes. The excellent properties of microstructured silicon make it a promising candidate for applications of infrared detectors, silicon solar cells, flat blackbody source and so on.
Influence of Nd2O3 on Structure and Dielectric Property of Zirconia Barium Titanate
Authors: Wang Sen , Li Zhi Hui , Liu Xin , Zhang Huan
Published: July 2011

Influence of Nd2O3 on structure and dielectric property of zirconia barium titanate has been investigated by means of XRD、SEM、EDXS. The results show that Nd2O3 will accelerate the grain growth if increasing the Nd2O3 amount and improve the sintering of the materials；Nd2O3 distributes mainly at the grain boundary in the materials and has influence on the anti-corrosion of grain surface; it will be helpful to increase the dielectric constant of the materials by increasing amount of Nd2O3 in the materials, but the resistivity will decrease.
Mechanical Properties of Electron Beam Cured MMT/MWNTs/Epoxy Composites
Authors: Lu Yan Yan , Li Hua , Ng Bo Kai , Chen Chen Xin , Kang Hong Mei , Jiang Li , Liu He Zhou
Published: July 2011

In this paper, electron beam radiation technology was applied to the preparation of MMT/MWNTs/epoxy nano-composites. The influences of the addition of Montmorillonite (MMT) and multi-walled carbon nanotubes (MWNTs) on the tensile properties of MMT/MWNTs/epoxy nano-composites were examined. The fracture surface of the composites was characterized by SEM as well. The results indicated that the composites have higher tensile modulus than that of the pristine epoxy resin.
Solving the Splitting Resilient Modulus of the Asphalt Mixture
Authors: Luo Zuo Fen
Published: July 2011

The finite element software was applied to simulate the splitting test of asphalt mixture, and the computational formula of resilient modulus was fitted out. On the basis of the measured resilient deformation from the splitting test, the computation process of splitting resilient modulus of the asphalt mixture was illustrated in detail. The splitting resilient moduli of the asphalt mixtures at three temperatures were analyzed. Finally the resilient moduli of the asphalt mixture measured through three kinds of tests were compared with each other. The results are of significance in the determination of resilient modulus of the asphalt mixture and parameter selection in specifications for asphalt pavement design.
Microstructure and High Temperature Oxidation Resistance of TiC/Ti-25Al Composites
Authors: Wang Hui Gai , Song Yan Pei , Wang Fei , Wei Zun Jie
Published: July 2011

With the reaction between titanium (Ti) sponge, high purity aluminum (Al) and TiC/Al inter-alloy, non-consumable arc melting technique has been successfully used in situ synthesize Ti matrix composites of Ti-25Al and Ti-25Al-1.5C. The composites oxidized at 900°C for 5~60h in static air. The influences of carbon content to oxidation kinetics of composites were analyzed. The surface morphologies and cross-section microstructures of the oxidation scales were examined by scanning electron microscope (SEM) with energy dispersive spectrometer (EDS). The results show that the isothermal oxidation kinetic curves of composites mainly follow parabolic rate law. The surface oxides of two materials are mainly columnar TiO2, while the grain size of Ti-25Al-1.5C is smaller than that of Ti-25Al. The cross-section microstructure of the oxidation scales of Ti-25Al are layered constructions which grow in alternating way. The oxides of Ti-25Al-1.5C are mainly around the carbide particles, the oxidation resistance of which is stronger than Ti-25Al when oxidized for long time.
Synthesis of BaCO3 Nanostructures with Different Morphologies in Water/Room-Temperature Ionic Liquids Mixed Solvents
Authors: Liu Feng , Lin Rong Yi , Wang Zhi , Liang Jie
Published: July 2011

Barium carbonate (BaCO3) crystals with different morphologies were synthesized using BaCl2·2H2O by a carbonation method in water/ionic liquids (ILs) mixed solvents. The as-prepared products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the results indicated that the types of ILs and the mole ratio of water to ILs played important roles in determining the morphologies of the products. The analysis of the XRD pattern showed that ILs had an influence on the crystallinity of BaCO3. When the mole ratio of water to ILs increased, the size of BaCO3 crystals increased and the morphology gradually changed from spherical to oval and rod-like. A microemulsion model was employed to explain this mechanism.
Preparation of Composite Ground Calcium Carbonate in Ca(OH)2–H2O–CO2 System and Characterization
Authors: Huo Chao , Shen Jia Yuan , Xia Qing Hua
Published: July 2011

Ground calcium carbonate (GCC) is usually of smooth/flat surface and pointed edges angles which have disadvantageous effects on the mechanical properties of composite polymer materials filled with the powder. Nanometer calcium carbonate reactants would deposit, nucleate and grow on surface of ground calcium carbonate with micron grain size by adjusting suitable technical parameters in Ca(OH)2–H2O–CO2 system. Compared with the uncoated powder, composite ground calcium carbonate (CGCC) is of rough surface, blunt edges, larger specific surface area, larger in whiteness. In this paper, we reported the successful preparation of CGCC particles, and found GCC/Ca(OH)2 weight ratio was the key parameter. Some technological parameters were mainly analyzed for the coating process. Furthermore, We also prepared nanosized calcium carbonate coating GCC at higher temperature (40 °C) using additives. Filling tests showed that a rough surface of the CGCC enhanced contact opportunities and improved the interface between polymer and CGCC blended with polypropylene (PP).
Electro-Generation of Furfural Alcohol in Ni-P-MCMC/mCS Bipolar Membrane Equipped Electrolysis Cell
Authors: Chen Xiao , Hu Yan Yu , Guo Zhen Zhen , Chen Ri Yao , Zheng Xi , Chen Zhen
Published: July 2011

Based on the actual conditions during industrial production, this paper proposes an improvement method and solution to the typical grinding process model and derives a mathematical model of grinding process that’s suitable for industrial production. Sampling analysis and laboratory experiments of the production process were conducted, the derived model was tested, and the results show that particle size distribution curve obtained from the improved model is similar to the actual product, which means that the improved model can be applied to simulate industrial grinding process.
Hydrothermal Synthesis and Characterization of Ca-Mg-Al Hydrotacite-Like Compounds
Authors: Zhang Mao Lin , Gao Yuan , Li Long Feng
Published: July 2011

Ca-Mg-Al hydrotalcite-like compounds (CaMgAl-HTLcs) were synthesized by a hydrothermal method, and characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential thermal analysis (DTA) techniques. The effects of the medium pH value, the molar ratio of the raw materials, the reaction temperature and the reaction time on the structure of CaMgAl-HTLcs were studied. The results showed that increasing treatment temperature and reaction time could improve the crystallinity and monodispersity of hydrotalcite-like compound particles. And well-defined CaMgAl-HTLcs could be prepared at a pH value of 10~11 with n (Mg+Ca): n (Al) = 1~3 and n (Mg): n (Ca) = 1~3.
X-Ray Characterization and Crystal Structure of SBT Doped with V2O5
Authors: Lv Su Hua , Guo Shu Lang , Ji Hua
Published: July 2011

SBT Ferroelectric Materials are prepared by solid reaction sintering process after doping V2O5 to SBT bulk and its properties are researched. The results show that this method can decrease sintering temperature , change the grains from rod to plate shape, increase grains size and lead to the grains growth with c-axis. And there are ferroelectric 90b domains in SBTV crystal .
Preferential Sorption of Minerals on Calcium Hydroxide of Hydration Productions of Cement
Authors: Zhu Hong Bo , Wang Pei Ming , Zhang Ji Dong
Published: July 2011

Forming progress of hydration productions CH are analyzed in this paper by ways of SEMs of hardened cement paste with or without ground granulated blast furnace slag and high-calcium fly ash. It presents that minerals with latently hydraulic or pozzolanic are apt to absorb CH crystal to grow around it. There are clearly hydraulic reactions in the partial surface of mineral grains connecting with CH crystal and there is little hydration in the part without CH surrounding. It indicates that increasing the absorbability of mineral grain for CH crystal is probably a useful method to advance reactivity of minerals with low activity.
Comparing Tests on Water Relating Stability of Polyester and Polyacrylonitrile Fiber Reinforced Asphalt Mixture
Authors: Song Jian Xue , Chang Chuan Li , Yang Hai Rong
Published: July 2011

Four kinds of fiber reinforced asphalt mixture formula are made, i.e., non fiber, polyester fiber, polyacrylonitrile fiber and the compound of the last two fibers, and then the Residual Marshall Stability (RMS) tests and Residual Cleavage Strength (RCS) tests are carried out. It is found that with the adding of fiber, the RMS is raised from 88% to 92% and the RCS from 86% to 88%. In the view of water-relating stability enhancement, the compound fiber is the best, the polyacrylonitrile fiber is the second, and the polyester fiber is at last, however, it is still better than plain asphalt mixture. More compaction work should be done on fiber reinforced asphalt mixture in practical engineering.
Nucleation Features of the Magnetite Fe3O4 Nanoparticles with the Size of 30-40 Nm for the Hyperthermia Applications
Authors: Zhu Ping , Zhuang Lin , Liang Rui , Xu Yue , Shen Hui
Published: July 2011

Magnetite Fe3O4 nanoparticles of 30-40 nm with a low coercivity are ideal for the hyperthermia applications. The Fe3O4 particles were prepared by oxidizing Fe2+ iron with a weak oxidant NaNO3 in a N2-deaerated aqueous NaOH solution (pH=12-13) at various temperatures below 30 °C. The nucleation features are explored. When the reaction temperature increases, the particle size decreases and the nucleation time shortens. At the two stages of the synthesis reaction, the coercivity is mainly affected by the saturation magnetic flux density and particle size, respectively.
Numerical Simulation on Laboratory Triaxial Test of Composite Soil with Roots
Authors: Huang Yan Yan , Liu Kai Fu , Zhu Yi Jun , Xie Xin Yu , Yang Xiang Ru
Published: July 2011

Numerical simulation is a good method for studying some academic problems in the engineering. Laboratory triaxial tests of composite soil were used widely in order to understand the stress-strain relationship. But the deformation of composite soil in laboratory triaxial tests is difficult to measure in some situation. Numerical simulation on laboratory triaxial test of composite soil with roots is carried out to see how the deformation of composite soil developed under the pressure on the specimen. Drucker-Prager constitutive model was used in the numerical simulation of finite element analysis. The results show that the numerical simulation of finite element method using Drucker-Prager constitutive model is suitable for studying the deformation development of composite soil with roots. The research results are important for understanding the deformation development of laboratory triaxial test of composite soil with roots.
Dehydration Process of Calcium Silicate Hydrate during Heating in the Air
Authors: Lu Lin Nu , Yu Shu Mei , He Yong Jia , Hu Shu Guang
Published: July 2011

Investigation on the continuous dehydration process of calcium silicate hydrate with C/S 1.5 during heating in the air was carried out. Results showed that the heating at 200°C of C-S-H resulted in decreasing basal spacing from 1.2 nm to 1.0 nm, and the basal spacing disappeared as the temperature raised to 400°C. Small amount of the dehydrated calcium silicate hydrate, portlandite and calcite were detectable in the heated sample at 400°C. The phases in the samples heated at 500°C and 650°C are β-C2S, quartz, and calcite. At 800°C and 900°C, α′-C2S, β-C2S, and quartz are main phases in the heated sample.
Preparation and Properties of Alkaline-Earth Silicon Oxynitride Glasses
Authors: Lian Zhi Hong , Wang Shi Lan , Tian Li Fei , Ge Wei Qing
Published: July 2011

All Samples of alkaline-earth silicon oxynitride glasses were synthesized by conventional high-temperature melting reaction. The infrared spectra of all glasses were studied. The results show that the band between 800 and 1300 cm-1 becomes wider and loss intensity with increasing N content. With the same starting N content, glasses prepared of different alkaline-earth oxides show different infrared spectra. The absorption bands of CaO-SiO2-Si3N4, BaO-SiO2-Si3N4 glasses are wider than SrO-SiO2-Si3N4 glass.
Study on Production Performance Simulating the Low Permeability Dual Media Gas Reservoirs Pre and Post Fracturing
Authors: Wang Li Ying , Gao Shu Sheng , Xiong Wei , Liu Hua Xun
Published: July 2011

Mathematical model of dual media reservoir fracturing wells was established and the corresponding numerical calculation program was developed based on the special relationship between porosity and permeability of dual media low permeability gas reservoirs. Through comparative analysis of numerical results of production performance pre and post fracturing, effects of cross flow coefficient and fracture penetration ratio were well studied. The results show that: after a period of production, pressure decline of the gas well decreases linearly with time, whether fracturing or not, showing pseudo-steady-state characteristics; in the early stage, pressure drop in the vertical well pre-fracturing is an order of magnitude larger than the post-fracturing well in the logarithmic coordinate; the less developed the natural fracture is, the smaller the cross flow coefficient is, and the more significant role the fracturing plays in yield increasing; when the fracture penetration ratio is between 0.25~0.50, it has less impact on production, so it is suggested that the fracture penetration ratio is controlled at about 0.25 in actual dual media dense gas reservoirs.
Microstructure and Property of 700MPa Ti Microalloyed High Strength Steel Produced by EAF-CSP
Authors: Gao Ji Xiang , Mao Xin Ping , Chen Qi Lin , Li Lie Jun
Published: July 2011

High strength steel ZJ700MC with yield strength grade of 700 MPa was successfully developed by Ti micro-alloyed technology in the EAF-CSP line at Zhujiang Steel. The composition design, smelting process, continuous casting and rolling process of the steel, as well as the mechanical properties of the hot-rolled product are introduced in the paper. An analysis on the strengthening mechanism of the high strength steel shows that the enhanced strength and toughness of the steel were caused by the refinement of ferrite grain and the precipitation strengthening of TiC.
Numerical Simulation of the Flow of Gases in a Large-Scale Electroslag Furnace
Authors: Yan Chen , Li Ying , Zhai Ying Ying , Sha Yu Hui
Published: July 2011

This paper reports a CFD modeling study on the flow of gases in an electroslag furnace during Protective Gas Electroslag Remelting(PESR) process by a commercial code FLUENT. The Realizable k−ε turbulence model, Do radiation model and Mixture model are amply used in FLUENT code to compute the flow of gases in the furnace under different argon gas flow, and the influence of argon gas flow on air volume fraction in the furnace is obtained. Finally, a suited suggestion on argon gas flow during PESR process is presented.
Basic Properties of Masonry Polypropylene Fiber Cement Mortar
Authors: Liang Na , Zhang Xiao Yan , Li Feng Lan
Published: July 2011

Experiments were carried out to investigate such basic properties as workability and strength of masonry cement mortar affected by mass content of polypropylene fiber. The results show that proper mass content of polypropylene fiber is helpful for effectively adjusting consistency and layering to bring better workability of fresh mortar, the relative higher bending strength of mortar can be got by admixing reasonable mass content of polypropylene fiber while slight improved compressive strength reaches. The relationships of water to cement ratio and mass content of polypropylene fiber in affecting these basic properties of masonry mortar are analyzed, which can be as reference for selecting optimum water to binder ratio and mass content of polypropylene fiber in practices.
Study on Flexural Strength and Flexural Modulus of Elasticity of Cement Stabilized Aggregate
Authors: Zhang Peng , Wei Xiao Hang
Published: July 2011

The aim of this study was to study the effect of curing period and cement content of the specimen on flexural strength and flexural modulus of elasticity of cement stabilized aggregate. Four specimen curing periods (7 d, 14 d, 28 d and 60 d) and four different cement contents (4%, 5%, 6% and 7%) were used. The results indicate that the flexural strength and flexural modulus of elasticity of cement stabilized aggregate are increasing with the increase of specimen curing period. Besides, with the increase of cement content, there is a tendency to increase both in the flexural strength and flexural modulus of elasticity of cement stabilized aggregate. The actual cement content should be chosen according to the actual condition of the project.
Microstructure and Wear Properties of Laser-Clad NiCrBSi Coating
Authors: Guo Yong Qiang , Zhao Hong Wei , Sun Rong Lu
Published: July 2011

NiCrBSi coating was prepared on the surface of 45 steel by CO2 laser. The microstructure of the clad layer was characterized by SEM、EDS and XRD. The microhardness and wear resistance of the laser clad layer was examined. The results show that laser clad layer can be achieved under technical processing parameters and that the good metallurgical bonding is formed between the coating and substrate. The coating is uniform, continuous and free of pores and cracks. The microstructure of the coating is mainly composed of g-Ni, Ni3B, CrB and Cr23C6 particles. The microhardness of the coating (500～650HV0.2) is distinctly higher than that of the substrate(240～250 HV0.2). The clad layer is reinforced by particles and grain-refining, resulting in greatly increase in wear resistance comparing with 45 steel.
Surface Crack Search and Marking on Materials with Regional Phase Unwrapping Technology
Authors: Zhang Yao Ting , Huang Min Jui
Published: July 2011

Depending on the size of sets, a wrapped phase map is unwrapped by either region or pixel. In region phase unwrapping, the jump point threshold value is adjusted to search the region boundary after filtering a wrapped map with higher noise and then phase unwrapping ±2nπ in each region without filtering. The latter compares if the phase difference of adjacent pixels is greater than π as a reference for determining pixel point ±2π to perform phase unwrapping point by point. Although the former unwraps phase by means of boundary search and the latter with the phase difference of adjacent pixels, phase unwrapping errors occur in both cases in detecting surface cracks on materials as data on both sides of a crack are discontinuous. This paper proposes a solution for phase unwrapping on discontinuous surfaces by means of crack search and marking with region assembly phase unwrapping technology to locate boundaries in both region splits and crack splits and further extends the scope of application of region assembly phase unwrapping.
Experimental Investigation of Fretting Fatigue of Train Axles under Rotating Bending
Authors: Wang Wen Jing , Wang Meng , Yang Guang Xue , Xie Ji Long
Published: July 2011

In railway transportation, the press fit of wheel and axle is typically causing fretting damage and it is also an important issue relative to the safety of railway. To examine the fretting damage of the interference fit of wheel and axle the fretting fatigue test under 4-point rotating bending loads is carried out based on samples, as well as the fretting fatigue damage rule is studied. The test results show that the fretting causes the fatigue limit to decrease significantly and all of the fracture sections occur at the contact edges of the fitting zone with the sleeve.
The Comparison of Fractal Dimensions of Cracks on Reinforced Concrete Beam
Authors: Sun Hong Quan , Ding Jun
Published: July 2011

In the paper, fractal geometry is used to study the crack evolving process of reinforce concrete beams. The fractal dimensions on surface of the reinforced concrete beam and the mechanical properties of the beam have the linear relationships perfectly. In order to compare the accuracy of the fractal dimensions, box counting method and the digital image box method in practical engineering are used to calculate the fractal dimension separately. The advantages and the disadvantages of these methods are analyzed. And the calculating conditions of these two methods are obtained. The research result gives a better way for determining the fractal dimension of the cracks on the reinforced concrete beam.
Microstructure and Abrasive Wear Properties of Plasma Sprayed Nanostructured Al2O3-TiO2-ZrO2-CeO2 Coatings
Authors: Wu Wei Qin , Li Qiang , Wei Zhen Yi , Ye Hui
Published: July 2011

Al2O3-TiO2-ZrO2-CeO2 coatings formed via a plasma spray approach. The optimal spray parameters of plasma sprayed nano-structured coating were determined by orthogonal experimental design, based on porosity, bond strength of the coatings and the partly melted(PM) zone percentage. Microstructure of the plasma sprayed nanostructured Al2O3-TiO2-ZrO2-CeO2 coating sprayed on the optimal spray parameters was analyzed. Wear map was established by wear experiments. The results show, nanostructured coating contains fully melted (FM) zone and PM zone, the increasing of the critical plasma spray parameter (CPSP) promote the decreasing of the PM zone percentage and the increasing of the bond strength of the coatings. The composition phases of the powder reacted to each other during the plasma spraying process. FM and PM zone resulted from fully melted droplets and partly melted particles respectively. Nanosized crystals and amorphous particles exist in the PM zone, liquid phase sintering is taken place in the PM zone. The main wear mechanism of plasma spraying coatings are plastic deformation and microplow, microfracture and grain spalling, fracture and delamination at different normal load and sliding speed in dry friction.
Duplex Stainless Steel Microstructure Display and Microscopic Study
Authors: Na Shun Sang , Zhang Guo Tao , Xu Qian , Gong Jin Hua
Published: July 2011

Several chemical corrosives which show the microstructure of Cr13 stainless steel are prepared. The paper introduces their methods and conditions of use and compares to their corrosive effects. The results indicate that corrosive which contains copper salt can make microstructures displaying clearly and have good reproducibility. In addition, it also has others advantages, for example, operation method and formula is simple and it can be preserved for long time. The paper provides convenient conditions for stainless steel optical microscope analysis.
Design and Experiment of Electromagnetically Induced Acoustic Emission for Metal Crack Detection
Authors: Zhang Chuang , Liu Su Zhen , Yang Qing Xin , Jin Liang , Kan Yu Huai
Published: July 2011

A new electromagnetically induced acoustic emission technique (EMAE) is presented in this paper. It does nondestructive detection with the effect of dynamic electromagnetic loading to generate a stress field stimulating stress waves from the defects. Theoretical analysis and experiment of the EMAE is carried out. The large pulse current generator which is used in electromagnetically induced acoustic emission (EMAE) is designed based on the energy storage of the capacitor. Applying to the EMAE experiment, it can achieve the expected effect and locate the defect in the aluminium plate. This work laid a good foundation for the engineering application of EMAE.
Realization and Analysis of Bending Fatigue Strength Test for Gears under Random Loading
Authors: Hu Jian Jun , Xu Hong Bin , Zu Shi Hua , Gao Xiao Wang
Published: July 2011

For the bending fatigue under the random load condition, the Miner cumulative fatigue theory was analyzed qualitatively. Random amplitude fatigue load spectrum for experiments was compiled according to that gears work under the load with Gaussian distribution load spectrum. Gear bending fatigue was carried out by the method of group test under the conditions of random load on the electro-hydraulic servo testing machine. Then the P-S-N curve of bend fatigue was got under Gaussian distribution load spectrum with particular coefficient of variation. Experiments prove that fatigue life from the result of random luffing amplitude fatigue experiments is lower than that from constant amplitude fatigue experiments, in which the upper limit of fatigue loads is the mean of load spectrum. It will be not reliable to estimate the bending fatigue life of gears that in the actual service.
Damage Evaluation of 16Mn Steel in Tensile Test
Authors: Wang Hong Wei , Luo Hong Yun , Han Zhi Yuan , Zhong Qun Peng
Published: July 2011

This study was focused on damage monitoring and estimation of 16Mn steel structures. This study used acoustic emission (AE) cusp catastrophe model to estimate the time at which the state of 16Mn steel will change from elastic deformation to yield deformation. Firstly, the tensile test of 16Mn steel plate specimens was monitored with acoustic emission technique. Secondly, a acoustic emission cusp catastrophe model was establish based on cusp catastrophe theory and acoustic emission signals. Finally, some catastrophe time was estimated with AE cusp catastrophe model. At this catastrophe time, the state of 16Mn steel plate specimen might change from elastic deformation to yield deformation. The experimental results show that AE cusp catastrophe model can estimate the time at which the state might change from elastic deformation to yield deformation of 16Mn steel in tensile test.
Influence of Hoop Coefficient on Dynamic Response of Railway Bridge Protective Frame under Impact Load
Authors: Ju Ao Tian , Qu Shu Ying , Hou Xing Min , Wang Jin Tian
Published: July 2011

The paper analyzes that hoop coefficients of the concrete-filled steel tube influence on dynamic response of the railway bridge height limit protective frame under impact load by using ANSYS/LS-DYNA. Change hoop coefficient of the concrete-filled steel tube structure by changing steel tube wall thickness. The result shows that with increase of steel tube wall thickness, the average impact force of protective frame will increase and the displacement and deformation will reduce, and protective frame can resist greater impact load. It will provide the reference for design of railway bridge height limit protective frame.
Effect of TBC Residual Stresses by Uniform Growth of TGO and Typical Interface Topography
Authors: Wang Zhi Ping , Wang Huan , Han Zhi Yong , Zhang Qing
Published: July 2011

Considering the thermally-growth oxide (TGO) that grows between ceramic coating and bond coat interface and surface topography of bond coat in a TBC system, the effect of residual stresses distribution by growth of TGO and cone interface topography in thermal barrier coating was calculated. The calculating result shows that the residual stress of TGO interface is affected by interface topography unit size and topography distribution density obviously. The stress between TGO and ceramic coating interface is greater than the stress between TGO and bond coat interface. Stress concentrates in topography center and the maximal value is 870MPa.The stress decreases with the increase of topography quantity.
Laser Repair Cladding of K418 Ni-Base Superalloy by CoCrNiW Powder
Authors: Chen Chang Jun , Cao Qin , Zhang Min , Chang Qing Ming , Zhang Shi Chang
Published: July 2011

Laser cladding has been taken into consideration for repairing K418 Ni-based superalloy material with CoCrNiW powder.Composition of cladding materials was revealed by energy dispersive X-ray spectrum(EDS). The characteristic microstructure of the cladding layer and interface were investigated by using an optical microscope and scanning electron microscope(SEM).Cladding coatings were obtained for different process parameters, and a detailed study of the effects of these parameters has been carried out by SEM. Metallurgical bonding between the cladding layer and substrate materials was obtained.Effect of heat input on cladding cracking susceptibility has been studied to obtain optimum condition for crack-free welds. Variations in cracking susceptibility as a function of heat input is discussed with reference to metallurgical characteristics of the clads. The corresponding microstructure induced by different heat input was discussed in this paper too.
Influence of Silica Fume/Nanosilica on the Strength and Microstructure of Phosphoaluminate Cement
Authors: Lv Chen Jing , Ren Shu Xia , Tian Xiu Shu
Published: July 2011

The influence of Silica fume/Nanosilica on the Performance of phosphoaluminate cement was studied in the paper. The microstructure and morphology was determined by X-ray diffraction and scanning electron microscopy. The experimental results show that the phosphoaluminate cement with 4% of added Silica fume/Nanosilica(1:1) by weight of cement has an optimum splitting strength, in which the increase of splitting strength are about 15.1%,11.8% and 24.6% at 3days,7days and 28 days. The reason for causing the above results are the hydration rate and the amount of the hydrates of PALC with 4% Silica fume/Nanosilica have been increased significantly at different hydration time because of the role played by Silica fume and Nanosilica together.
Experimental Study on the Tribological Properties of Water-Lubricated Rubber Bearings
Authors: Wang You Qiang , Wang Mei Shu
Published: July 2011

Water lubricated rubber bearing is one of the most appropriate bearings widely used in submerged pump for drainage. The apparatus for studying the tribological behaviors of the water lubricated rubber bearings has been devised and established in the paper. The experimental studies on the tribological properties of the rubber bearings have been conducted under different load and velocity using the apparatus. Effects of load and velocity on friction coefficient of the rubber bearings have been estimated. The experimental results show that the friction coefficient decreases with increasing velocity; the friction coefficient increases at first and then decreases with increasing load; the friction coefficient increases sharply with the rising temperature. The experimental results also indicate that there is an appropriate bearing clearance which the friction coefficient is minimum.
A New Method of Numerical Differential and Time Domain Integral Based on the Analysis of Vibration Response
Authors: Hu Jie , Zhang Xi Nong
Published: July 2011

A new method of numerical differentiation and time domain integral was proposed in this paper, its idea was originated from the analysis of the time domain vibration response. As to numerical differentiation, the discrete sequence could be considered as the displacement response of an one degree-of-freedom system, and the velocity and acceleration response corresponding to the first and second order numerical differentiation. As to time domain integral, the discrete sequence could be considered as the acceleration response of an one degree-of-freedom system, and the velocity and displacement response corresponding to the first and second order time domain integral. All these work were established based on the discretization analysis of Duhamel integral. Numerical simulation result indicates the effective and better accuracy of this new method.
Cyclic Spectrum Analysis on Rolling-Element Bearing with Inner-Race Point Defect
Authors: Ke Wei , Zhang Yong Xiang , Li Lin
Published: July 2011

Vibration signal of rolling-element bearing is random cyclostationarity when a fault develops, the proper analysis of which can be used for condition monitor. Cyclic spectrum is a common cyclostationary analysis method and has a great many algorithms which have distinct efficiency in different application circumstance, two common algorithms (SSCA and FAM) are compared in the paper. The FAM is recommended to be used in diagnosing rolling-element bearing fault via calculation of simulation signal in different signal to noise ratio. The cyclic spectrum of practice signal of rolling-element bearing with inner-race point defect is analyzed and a new characteristic extraction method is put forward. The preferable result is acquired verify the correctness of the analysis and indicate that the cyclic spectrum is a robust method in diagnosing rolling-element bearing fault.
Flapping Mechanism Design and Aerodynamic Analysis for the Flapping Wing Micro Air Vehicle
Authors: Qin Yi , Zhang Wei Ping , Cheng Wen Yuan , Liu Wu , Li Hong Yi , Chi Peng Cheng , Meng Kun , Cui Feng , Wu Xiao Sheng
Published: July 2011

This paper introduces a biological flapping micro air vehicle (FMAV) with four wings, instead of two wings, where wing clap-and-fling of real insects has been mimicked. The total weight is 2.236g. A spatial linkage is implemented in the flapping wing system, which is symmetry. This can prevent the flapping wing MAV from tilting toward the left or the right in the course of flight. By using the computational fluid dynamics (CFD), it has been confirmed that the flapping wing system can utilize the clap-and-fling mechanism, which is essential to enhance the lift and thrust in the insect flight.
Influences of Semi-Rigidity of End-Plate Joints on Structures
Authors: Wang Qiong Fen , Liu Yuan Cai , Cao Liang , Yao Ji , Huang Jian Feng
Published: July 2011

Calculations of the end-plate semi-rigid joints are carried out with a FE-program ANSYS. Some results of the calculations are introduced in this paper. The influences of the joints semi-rigidity on the deformation, the bending capacity and the internal force of the structure are researched; the initial rotational stiffness, the elastic ultimate moment and the plastic ultimate moment of the steel joints and the composite joints are compared. Some results may be useful for the design of the end-plate semi-rigid joints.
Analysis of the Mixed Control System of Damper and TMD
Authors: Lin Qian , Xu Ze Yao , Zhang Jian Lin
Published: July 2011

Many new control techniques and energy dissipation systems which can decrease the response of wind vibration and earthquake. But there is less research on the mixed control system of Damper and TMD. In order to improve the shortcomings of Damper system and TMD system, combining their respective advantages reasonably, the mixed control system of Damper and TMD were analyzed in this paper. A 20-storey Benchmark model was used to compare the effects of various control systems under 2-directional earthquake. Taking the displacement reducing coefficient (DRF) as the objective function, Damper system, TMD system, and the mixed control system of Damper and TMD are optimally designed based on Genetic Algorithm (GA). Numerical results show that the mixed control system of dampers and TMD proposed in the paper can work in coordination and complement each other to achieve better control effect.