bluuebunny/crossref_metadata_2025 huggingface dataset:
Stability Analysis for Discrete-Time Stochastic Neural Networks with Mixed Time Delays via Delay-Paritioning
Authors: Zhou Xia , Zhong Shou Ming
Published: April 2011

This paper revisits the problem of stability analysis for discrete-time stochastic neural networks (DSNNs) with mixed time-varying delays in the state. Here the mixed time delays are assumed to be discrete and distributed time delays and the uncertainties are assumed to be time varying norm bounded parameter uncertainties. A new delay-dependent stability criterion is presented by constructing a novel Lyapunov-Krasovskii functional and utilizing the delay partitioning idea and free-weighting matrix approach, Which is less conservative than the existing ones. This criterion can be developed in the frame of convex optimization problems and then solved via standard numerical software. These conditions are formulated in the forms of linear matrix inequalities, which feasibility can be easily checked by using Matlab LMI Toolbox.
The Stress Analysis of Different Circular Saw Structures during Cutting
Authors: Wang Xiao Ling , Yin Zhong Jun , Li Yan Lin
Published: April 2011

In this paper, we analyze the stresses around the saw teeth of differently designed circular saw structures. We select a set of critical points around the saw tooth, then we calculate the equivalent stresses of these points and the maximum or minimum stresses of the different saws under different loads and rotational speeds. The saw structure factors that we examine include the diameter of circular saw blades, the depth of the circular saw, the saw tooth rake angel, the saw tooth height and the saw tooth shape. Based on our analytical results, we propose an effective approach to reduce the stress concentration around the saw tooth and thus prevent the saw tooth fracture.
The Mechanical Analysis of the Composite Reinforced Circular Saw Blade
Authors: Wang Xiao Ling , Yin Zhong Jun , Zhang Chao
Published: April 2011

Thinner saw blades cannot resist large lateral cutting forces due to their lower stiffness. In this paper we propose a composite reinforcement method to improve the mechanical properties of circular saw blades. We analyze and simulate the stress and strain fields of our proposed reinforced circular saws by Finite element method. Our analytical results contain not only influences of reinforcing parameters but also loading conditions on the lateral stiffness and the natural frequency of composite saw blades. Here the reinforcing parameters include: 1) the reinforcement location on circular saw blades, 2) the volume fraction of the reinforcements, 3) the number of the reinforcements; and loading conditions include: 1) the cutting force, 2) the rotational speed. Our composite reinforcement model and simulation results can contribute to a better design of circular saw blades.
Effect of Ruthenium on the Performance of Iron-Based Catalyst for CO Hydrogenation
Authors: Tang Qing Jie , Wu Wen Rong , Fan Shao , Liu Bo
Published: April 2011

A series of Iron-based complex catalyst were prepared by precipitation and immersion in order to study the effect of Ruthenium on the performance of Iron-based catalyst for CO hydrogenation in FTS. The distribution of products was studied for CO hydrogenation, and the reduction action of Iron-ruthenium complex catalyst was study by TPR. The results showed that the yield of the lower hydrocarbons in the products of CO-hydrogenation could be improved obviously with Ruthenium added, and the reduction action of Iron-based catalyst could be promoted obviously.
The Identification Analysis for Macro Distributions Curves of Functionally Graded Materials Properties Based on Materials Components
Authors: Ge Chao Feng
Published: April 2011

There are much complex internal microstructures of functionally graded materials, and the mechanical parameters of functionally graded materials structures varied with the space coordinates. Therefore, it is generally difficult to measure point by point macro distributions curves of functionally graded materials properties based on available experimental conditions. The prerequisite for various analyses of the functionally graded materials structures is the determination of macro distributions curves of materials properties parameters. In practice, only the spatial distributions of different material components can be controlled in the course of materials production. Therefore, the functionally graded distributions curves need inversing and identifying by the materials components. In the present paper, the inversion and identification technique was put forward based on the positive static and dynamic analyses by the microelement method, which was applied to do the scale-span analyses for macro responses of functionally graded materials structures based on the given materials components distributions in production.
Study on Mechanism of Laser Thermal Damage on Piston
Authors: Pang Ming , Liu Zhen Tao , Tan Jian Song , Liu Xiu Bo
Published: April 2011

The experiments of thermal shock damage on piston were conducted by shaped high power laser. Damage mechanism of thermal shock specimen was characterized by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The mechanical properties of thermal shock specimen were evaluated by microhardness. The corresponding mechanisms were discussed in detail. The results show that cracks originated from the interface of Al-matrix and intermetallic phase due to the thermal and mechanical misfit between these brittle components of the microstructure and the surrounding ductile matrix. Oxides of thermal shock crack can accelerate the damage of piston. There is a drop in the hardness of piston at all locations after thermal shock tests.
Research on Group Decision-Making Optimization Model of Urban Railway Traffic Network Scheme
Authors: Yan Hong Yan , Zhang Fei Lian
Published: April 2011

Aiming at the evaluation and optimization of urban rail transit network scheme, the optimization decision-making model based on group TOPSIS was advanced in this paper. The multi-attribute evaluation index system of urban rail transit network was established. Then the decision-making’s position matrix and the attribute weights were determined using the idea of group decision-making on the basis that group rationality was guaranteed , which aimed at the phenomenon that preference of decision-making existed and the reduction of decision-maker’s preference had influence on the result of decision-making. The network scheme was ranked based on TOPSIS method to arrive at a decision. The example in this paper has verified the effectiveness and practicability of the model.
Synthesis and Structures Characterization of Nano NiO by PDCG Technology
Authors: Cao Xian Hang , Qin Jin Feng , Niu Qian , Liu Si , Wang Wei
Published: April 2011

Nano NiO is prepared by Parallel Dropping Concentration Gradient method(PDCG)with nickel nitrate hexahydrate,ammonia and Tween-80.The structures and morphology of Ni(OH)2•nH2O and NiO are characterized by DSC,XRD,SEM and FTIR.The results shows that because of the desorption of solvent and physical adsorbed water, the weight of precursor changes slowly during 40-280°C, while the weight of compound material changes quickly during 280-480°C because of the loss of chemical adsorbed water and the decomposition of Ni(OH)2. Above 480°C,the weight of sample changes unobviously. SEM shows that nano NiO soft gathered to form particles under the effection of surfactant. XRD shows that nano NiO prepared by PDCG was cubic crystal and with an average particle size of 3.8 nm.
The Meshing Property Analysis of the New Sine Gears
Authors: Meng Fan Jing , Huang Dao Ye , Zhou Zhe Bo
Published: April 2011

Basing on the theory of the meshing principle and the differential geometry, deduced the contact wire function for the new sine gears. In explanation of the gear parameters influencing to the contact wire function, imitated the contact function using the regular changes values of the amplitude value H and the helix angle β with MATLAB. From the imitation derived the evolution of the contact wire influencing by the amplitude value H and the helix angle β. The contact wire moved following with the enlarge amplitude value H to the forward direction of the high tooth and the forward direction of the width tooth; The contact wire also moved following with the enlarge helix angle β to the negative direction of the high tooth and the negative direction of the width tooth. Thereby, in order to select the appropriate gear parameters provided basis.
The Present Situation of EMS and Solutions to its Difficulty
Authors: Li Zhi , Wen Zhi , Lou Guo Feng
Published: April 2011

With the development of global economy, energy situation has been more and more severe. The shortage of energy will no doubt be one of the bottlenecks, which restricts the social progess. Iron and steel industry is an important energy intensive industry, whose use of energy plays an important role in the national energy situation. Therefore, energy optimization is a serious topic for the iron and steel enterprises. Based on the systematic energy conservation, this paper raised the importance and necessity of Energy Management System for energy saving and optimization dispatching in Iron and Steel enterprises. It also describes its present situation and basic functions, in which general ways to the domestic construction of EMS are included. There is the analysis of the difficulty of its construction and solutions to it.
A Micro-Machined Ceramic Hot-Plate for Gas Sensor Applications
Authors: Xue Yan Bing , Tang Zhen An
Published: April 2011

A novel suspended ceramic hot-plate and wire-free bonding interconnection was investigated. The device was made on the popular alumina ceramic flakes with a platinum heater prepared by lift-off process. The structure of suspended beam was machined by laser micromachining technique. This contribution presents first results for single-layer’s ceramic hot-plates that include design, manufacturing and tests of such devices. The results show that the ceramic hot-plate has lower power consumption (280 mW at 400 °C) than classical ceramic gas sensors. Moreover, it has less expensive manufacturing and bonding process than Si manufacturing technology. Low power consumption and good performance at high working temperature (600 °C or more) makes it possibly to be used in some specific applications for gas sensors.
Design of New-Type Vertical Dredging Equipment for Coal Bunker
Authors: Zheng Jian Xin , Liu Chuan Shao , Tian Yue Hong
Published: April 2011

A new-type of dredging equipment for the coal bunker is designed to solve the clogging problem, which avoids the disadvantages of the existing dredging technology used in the collieries. The new dredging method borrows ideas from air cannon dredging technology, and applies dynamic high pressure generation principle. In the process of dredging, the rubber bullet in the launch canister is accelerated by the controlled high pressure air, and impacts the coal in the arch with high speed so as to recover the coal bunker. The dredging mechanism and process are expatiated and the main structures of the dredging equipment are introduced. The structure of the new type dredging equipment for the coal bunker is simple and the equipment is of high adaptability and safety.
Research on Nonlinear Dynamic Characteristics of Fluid-Conveying Pipes System
Authors: Hou Yu , Zeng Guo Hua
Published: April 2011

Lateral vibration equations of fluid-conveying pipes system are high order partial differential equations, and the analytic solution is difficult to obtain, so in this paper the numerical solution is obtained by the finite element method. Firstly, the finite element equations of lateral vibration of fluid-conveying pipes were set up, and four kinds of boundary constraints were proposed. The modal analysis of vibration system was carried out by using mode decomposition method, and the system responses were solved by using Newmark method. The impact of pipe span, flow rate, fluid pressure, flow rate disturbance and fluid pressure disturbance on the modes and responses of vibration system were studied. The research results provided theoretical support for the vibration reduction research of fluid-conveying pipes.
Wear Behavior of B4C Ceramic Nozzles
Authors: Feng Yi Hua , Liu Jian Hua , Deng Jian Xin , Zhong Geng Lei , Liu Min
Published: April 2011

B4C ceramic nozzle was produced by hot pressing, and wear behavior of the nozzle by SiC, white emery and umber emery abrasives were investigated, erosion wear mechanisms based on stress states analyzing with finite element method were studied. Results showed that the greater the hardness and grit size of abrasives, the more mess loss of the nozzle, the maximum stress appeared in entrance area of the nozzle and minimum stress in middle area, while the stress of exit area was lower than entrance area and higher than middle area. The nozzle exhibited a brittle fracture induced removal process in the entrance of the nozzle and a stress fatigue induced removal process in the middle of the nozzle under the condition of SiC abrasives impacting, and a stress fatigue induced removal process under white and umber emery abrasives impacting.
Preliminary Studies on the Functional and Structural Design of Forest Fire Helmet
Authors: Li Bo , Li Bin , Yang Hong Ze
Published: April 2011

In order to improve the performance of forest fire protection equipment, this paper proposes a new design concept of modern forest fire helmet. The scheme combines the functions of infrared thermal imaging, wireless communication and emergency oxygen making, which not only meets the security requirements in firemen’s present working, but also accords with the development of fire helmets at home and abroad. This helmet adopts the design conception of integration structurally, its weight and operation difficulty are both reduced, at the same time, accords with the Man-Machine Engineering. Moreover, using the three-dimensional processing software, this study realizes a simulation model of the designed forest fire helmet.
Properties of Lead–Free High Refractive Index Barium-Based Glass Doped with TiO2
Authors: Won-In Krit , Dararutana Pisutti
Published: April 2011

The effect of varying the TiO2–content on the lead-free high refractive index glass based on 25 wt% barium carbonate added in replacing lead oxide was prepared and its physical, optical, and electrical properties were investigated. Seven glass samples were synthesized and characterized by using an analytical balance, a refractometer, a LCR meter and an X-ray diffractometer. Specific gravity, refractive index, and dielectric constant increased linearly as the increasing of the TiO2-content. The amorphous state of modification of glass structure due to TiO2 addition was confirmed.
The Function Mechanism of Current Density on Antimony Nanopowder Prepared by Electrochemical Method
Authors: Xu Jian Lin , Yang Shu Hua , Zhang Li Hui , Kang Zhao , Guo Qiang
Published: April 2011

The nano-antimony particles with different shape, size and stability are prepared by electrochemical method under the dilute hydrochloric acid electrolyte including the surface dispersant OP-10 and different current densities. The influences of current density on the shape and size of nanometer antimony particles prepared by electrochemical method are analyzed by using X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR). The results show that nano-antimony powder can be prepared by electrochemical method, and the antimony powder possesses the crystal structure with orthorhombic hexahedron. The current density has a significant impact on the agglomeration, shape and size of antimony powder. The size and shape of antimony powder are determined by the nucleation rate of nano-antimony and combination capacity of antimony ions and OP-10 surface dispersing agents affected by current density. When the current density is 25mA/cm2, the average particle size is 12nm or so, the shape is spherical, and the nano-antimony particles are well dispersed and no agglomeration.
Finite Element Analysis on Thermal Structures of Heavy Machinery Gearbox
Authors: Mei Yi , Wang Fang Ping , Liu Qiao Ying , Mao Yu Tao
Published: April 2011

To solve the thermal deformation caused by thermal load of heavy machinery gearbox, it is established that coupled analysis model to carry out the analysis on box structure's thermal characteristic by using the finite element thermal structure coupled analysis. The model figures out the steady-state temperature distribution of the box, the results will be the boundary condition for box thermal structural coupled analysis. It is calculated which stress distribution and displacement cloud pictures of the box under the interaction of thermal and structural load. The results show that deformation of the heavy machinery gearbox is cased by structural loads and thermal loads. And the thermal load is an important factor that controls box deformation to ensure the accuracy and reliability of heavy gear transmission, which can not be ignored.
Design of Special Fixture for Micro High Speed Motorized Spindle
Authors: Lu Xiao Hong , Jia Zhen Yuan , Zhang Zhi Cong , Jia Xv
Published: April 2011

The fixture of motorized spindle significantly affect the vibration of micro high speed CNC milling machine, its performance can directly affect the machining accuracy of the entire micro milling machine. A special fixture of high-speed motorized spindle is designed in the paper and its static characteristics are checked by utilizing ANSYS finite element analysis software. To guarantee the sufficient strength of bolts and the safety of motorized spindle when the motorized spindle runs at high speed, theory analysis method and ANSYS finite element analysis method are used to make the strength check of the fixture. The designed special fixture for high speed motorized spindle plays an important part in the design of high-speed motorized spindle.
Fatigue Life Prediction of Notched Specimen under Multiaxial Cyclic Loading
Authors: Sun Guo Qin , Shang De Guang
Published: April 2011

The stress-strain response at notch root for notched specimen was computed by elastic-plastic finite element analysis (FEA) under multiaxial loading for GH4169. A uniform gouge length of the specimen was selected as the dimension of the FE model. The uniaxial fatigue data were used to describe the stress-strain curve. One cycle is divided to different load steps according to phase difference. Tension-torsion strain cyclic loading was implemented in FEA. Fatigue crack initiation life was predicted by Smith-Watson-Topper model, Shang-Wang and Sun-Shang models with the calculated stress-strain data at notch root. The result shows that the three models are suitable for life prediction of notched specimen under multiaxial cyclic loading for GH4169 alloy.
Elastohydrodynamic Lubrication Design of Planetary Gear Transmission
Authors: Bao Pei De , Xie Jun , Yin Xiao Qin , Yang Qi Zhi , Ma Lu Zhong
Published: April 2011

Based on elastic hydrodynamic lubrication (EHL) theory, an EHL model of the meshing between the sun gear and planet gear in planetary gear transmission was established. The EHL oil film thicknesses at meshing areas and those distributions for two operation cases were calculated: one case with the sun gear as the driving gear and another case with the ring gear as the driving gear. The Lubrication with second case was worse. Through the many comparing calculations the lubrication film thickness can be significantly increased by right parameter design. Reasonable raise of lubricant viscosity can get better gear lubrication. Increased gear pressure angle can greatly increase the oil film thickness. The increase of oil film thickness can improve the lubrication of gears and prevent wearing and reduce the production cost of gears, which have great practical value.
Research on Low-Pressure Common Rail Electrical Control Injection System of Dimethyl Ether Engine
Authors: Tao Jun , Zhang Guang De
Published: April 2011

According to such properties of DME as high saturated vapor pressure, low viscosity and easy formation of mixture with air, a CPC (Controllable Premix Combustion) low-pressure common rail electrical control fuel injection test bench of DME engine is developed through this research. In addition, an overall design of the test system, hardware and software development of electrical control unit (ECU) and a test on the test bench are undertaken. The software of ECU is programmed by using real time modular programming. It has the advantages of flexible programming, convenient transplantation and wide extending possibility. Test results show that the injector switch timely, spray powerfully and pulverize perfectly. The software accomplishes many tasks such as signal acquisition as well as real-time control requirement of engine operation. Test result also shows the feasibility and good comprehensive performance of low-pressure common rail electronic system for DME fuel.
Tool Path Planning of the Micro Cowled Integral Impeller
Authors: Han Zhen Yu , Liu Run Bing , Fu Hong Ya
Published: April 2011

The micro crowled integral impeller is one of the key parts of aeroengine. It is difficult to machine for its complex structure and small dimension. In this paper, the tool path planning scheme of micro crowled integral impeller is researched, which lays foundation for the numerical control machining of the part. To begin with, considering the feature of impeller’s structure, a kind of processing route is proposed and the processing regions are divided, which satisfy the demand of accuracy and efficiency. Then, the tool path planning scheme of the impeller is put forward, which is regular and is more suitable for a large-diameter tool to fulfill the machining process. Finally, machining simulation is carried out to prove the feasibility and correctness of the proposed path planning scheme.
Evaluation of the Adhesion of Diamond-Like-Carbon Coronary Stent
Authors: Feng Hai Quan , Wang Zhi Guo , Shuzou Yamashita , Tatsuyuki Nakatani
Published: April 2011

The excellent biocompatibility and antithrombotic properties of Diamond-like Carbon films (DLC) have been widely confirmed in several clinical trials of artificial heart valves and blood vessels. In recent years many researchers were doing a lot of research coating DLC as the surface of coronary stents. Considering coronary stents’ plastic deformation occurred in installation and expansion process, surface coating was required to follow the plastic deformation of substrate materials, and it should be with excellent adhesion, without cracking and falling off. According to this, we created a method with different concentration gradient of silicon content on different thickness of DLC coating, and found a plastic deformation required by DLC coated stent, which with excellent adhesion and not cracking. In order to facilitate analysis and comparison, we compared it with two products abusing on the market under the same conditions and got a good result, which provided strong evidence for the product development of DLC coated coronary stents.
Microstructure Characteristics in Continuous Cooling Transformation of an Nb Microalloyed Steel
Authors: Yang J. H. , Liu Q. Y.
Published: April 2011

Deformation dilatometry has been used to simulate controlled hot rolling followed by controlled cooling of a Nb microalloyed pipeline steels, the microstructure and transformation characteristics in the steel and the effect of deformation on transformation are studied. According to the results of both dilatometry measurements and microstructure observations, the continuous cooling transformation curves (CCT) of the tested steels are constructed. The results show that Nb content and deformation enhance the formation of acicular ferrite; the microstructure of the steel range from PF, QF to AF with increasing of cooling rates from 0.5 to 50°C /s in a two stages controlled rolling and the microstructure revolution is sensitive to cooling rates when it is lower than 5°C /s, however, when the cooling rate increasing further, the microstructure didn’t change very much but M/A constituents in matrix is refined and dispersed.
Effect of Dispersion Medium and Dominated Evaporation on the Pattern Formation of Colloidal Suspension
Authors: Ma Wen Jie , Wang Yu Ren
Published: April 2011

We study the effect of dispersion medium and dominated evaporation on the drying process and pattern of thin liquid layer colloidal suspention. Panasonic camera is used to capture the drying process and macroscopic pattern. It is shown that drying patterns are sensitive to the dispersion medium. As the volume ratio of ethanol in aqueous ethanol colloidal suspension increases, the evaporation rate increases, and film in the center becomes smaller and thinner, obvious broad-ring pattern can be observed. We suggest that difference in dispersion medium changes the evaporation rate, which has a direct proportional variation with strength of Marangoni convection. Furthermore, convection strength has great influence on self-assembly of colloid particles and the pattern formation of colloidal suspension. We design two simple experiments to change the evaporation rate and convection strength in order to verify the conclusion above. Broad-ring patterns with spray-like round edge at higher evaporation rate are obtained. Uniform film forms at lower evaporation rate.
The Measurement of LED Domain Wavelength Based on LabVIEW
Authors: Lin Wei Guo , Wang Yu Fu , Yang Ming Zhong
Published: April 2011

The domain wavelength is the most important colorimetric parameter of tested LED, it decides the LED color quality. The data acquisition system is build of linear CCD, monochromator，and PCI data acquisition card, which can obtain the chart of distribution value of 1urninous intensity and color coordinate of LED with LabVIEW. This paper present measurement method based on the table method, the measurement method is looking-up two domain wavelengths which distance is 1nm through slope which get from testing LED color coordinate and white light LED coordinate, and calculate the domain wavelength of testing LEDs using LabVIEW and mathematic interpolation, the measurement error of domain wavelength is 1 nm.
Comparative Study of Structure and Pickling Characteristics of Oxide Scale Formed on Strips Produced by TSCR and Conventional Process
Authors: Zhu L. M. , Yang J. H.
Published: April 2011

The microstructure and pickling characteristics of oxide scale formed on hot-rolled SPHC steel strip produced by different processes were investigated based on structure observation, weight loss and corrosion potential measurements. The results show that the scale formed on strip produced by TSCR consists of mainly magnetite (Fe3O4) and little wustite (FeO), hematite (Fe2O3), and that in conventional process is composed mainly wustite (FeO) and little magnetite (Fe3O4), hematite (Fe2O3). The shape of the open-circuit potential transient is determined crucially by the oxide scale structure. Time to reach a steady-state value of open-circuit potential of strip produced by TSCR is longer than that in conventional process. Both the stability of the scale in pickling solution and the effectiveness of descaling could be evaluated and predicted by measuring the change of electrochemical potential during acid pickling.
The Design and the Topological Optimization of the Tracked Triangle Wheel’s Basic Frame
Authors: Yang Li Hao , Wang You Jun , Qin Zhong Bao
Published: April 2011

In this paper, the stress and strain of the tracked triangle wheel’s original basic frame which is used on shovel loader were analyzed in AnsysWorkbench. And topological optimization method was then used to optimize the basic frame so as to find out its best bearing structure, after which the original basic frame was improved and designed for the second time in the solidworks environment. And then, the stress and strain of the basic frame’s new structure were analyzed again. In the end, a comparison was carried out between the finite element analyze results before and after the topological optimization. According to the comparison, the weight of the basic frame is reduced by 22.5% while the stress and strain nearly keep the same.
Study on the Damage Mechanism of Bridge Pier and Foundation by Turbulent Debris Flow
Authors: Liu Li , Chen Hong Kai , Tang Hong Mei
Published: April 2011

The debris flow is the uppermost water-destroyed type of highway, which caused large direct economic loss annually in china, especially in mountainous area highway small bridges and culvert damaged seriously. This paper started from the theory of debris flow two-phase flow, it is divide turbulent debris flow into liquid and solid, and with the turbulent debris flow wash against bridge pier increased, the erode depth overpass the burial depth of foundation, base bearing capacity reduced gradually and then result bridge pier instability; in addition for the strong force of impact of debris flow resulted in resistance to capsizing weaken. The damage of bridge and culvert’ foundation mainly duo to the erosion, which lead to the erode depth overpass the burial depth of foundation, furthermore, debris flow force of impact greater then structure resistance and result the structure instability and damaged.
Thermoelectric Characteristics of Pb- and La-Doped Bi2Ba2Co2OY Ceramics
Authors: Hao Hao Shan , Yu Hai Peng , Zhao Li Min
Published: April 2011

Pb- and La-doped (Bi,Pb)2(Ba,La)2Co2Oy ceramics were prepared by solid-state reaction method and the effect of element doping on the thermoelectric characteristics was investigated. Pb and La doping increased the electrical conductivity and transformed the conduction from a metal-like behavior to a semiconducting one. Different from the undoped samples, the values of Seebeck coefficients decreased with the increase of the temperature in the Pb- and La-doped samples. Pb doping in Bi2Ba2Co2Oy system improved the thermoelectric characteristics at high temperature and Pb/La co-doping improved thermoelectric characteristics at low temperature.
Curing Behavior and Thermal Properties of Me-SSQ/Cyanate Ester Resin Organic-Inorganic Hybrids
Authors: Zhang Zeng Ping , Chen Shuan Fa , Pei Jian Zhong
Published: April 2011

A kind of nonfunctional silsesquioxane (SSQ), methylsilsesquioxane (Me-SSQ), was used to modify cyanate ester resin (CE) in this paper. First, methylsilsesquioxane (Me-SSQ) was synthesized by the hydrolysis and condensation of methyltriethoxysilane. Then a series of Me-SSQ/CE hybrids containing 0wt%, 1wt%, 5wt%, 10wt% and 20wt% of Me-SSQ were prepared. The effect of Me-SSQ content on the curing behavior and thermal properties of materials was investigated by using Fourier transforms infrared (FT-IR) spectroscopy and thermogravimetry (TG), respectively. FT-IR results indicate that the addition of Me-SSQ does not show significant effect on the conversion of CE. However, TG data show that Me-SSQ improved the thermal properties of CE greatly.
Research on Compound Powder of Bonded NdFeB Magnets from Injection Molding
Authors: Qin Wan Zhong , He Jie , Zhao Wen Tong
Published: April 2011

The injection molding of magnetic powder could cost-effectively mass-produce net shape magnets. In order to prepare the injection molding bonded NdFeB permanent magnet material with better combined properties, the effect of binder on the magnetic property, mechanical property and fluidity of injection molding magnets and its mechanism microcosmically were investigated. The effect of additives such as silicone coupling agent, compound lubricants and antioxidant on the properties of injection molding magnets are discussed. The injection molding bonded magnets were prepared by using the MQP-B rapidly quenching NdFeB magnetic powder and polyamide 12. The magnetic properties are :Br=0.539T, Hcb=345.37kA/m, Hci=681.02kA/m, and (BH)max=47.37kJ/m3.
Influence of Surface Wettability on Dropwise Condensation Heat Transfer
Authors: Chen Yun Fu
Published: April 2011

For finding influence of the surface wettability on dropwise condensation heat transfer, a model for dropwise condensation heat transfer has been established based on the drop size distributions and the heat transfer rate through a single drop with considering influence of contact angle to heat transfer. It has been shown based on the proposed model that up to a drop radius of 5μm, the rate of decrease in the drop population density is not as steep as the rate for a drop radius greater than 10μm, because coalescence between drops starts taking place. Varying the contact angle changes the drop distribution; higher the contact angle, lower the departing droplet size and large number density of small droplets. Heat flux first increases and then decreases with increasing contact angle under the temperature difference condition.
Laser Ablation of Alumina Ceramic in Sodium Hydroxide Solution with Nd:YAG Laser
Authors: Zhu Shao Feng , Yuan Gen Fu
Published: April 2011

In this paper, alumina ceramic samples were ablated with HGW-300 solid laser in sodium hydroxide solution medium. The morphology and structure of the ablated surface were investigated by SEM and XRD. The results show that, the mass loss increased with increased processing voltage. With the laser scanning speed increasing, the mass loss of alumina ceramic sample decreasing. While pulse width is 1.4ms, the mass loss of the sample gets maximum.When the repeat frequency is 40Hz, the mass loss of the sample in 20g/L sodium hydroxide solution reaches a maximum and then drops down. Corrosive medium can increase the mass loss of alumina. When the samples were tested in 20g/l sodium hydroxide solution, their mass losses is higher than in any other solutions.
Synthesis and Properties of Cellulose Stearate
Authors: Huang Feng Yuan
Published: April 2011

Cellulose Stearate (CS) was synthesized by acylating microcrystalline cellulose (MCC) in homogeneous system with p-toluenesulfonyl chloride (Tos-Cl) and stearic acid (SA). The reactive conditions were discussed. The molar ratio of AGU:SA:Tos-Cl was the key factor which affected the degree of substitution (DS) of CS. In the present paper, CSs with DS ranging from 0.64 to 2.35 were prepared under mild condition. The structure of CS was characterized by FT-IR and 1H-NMR, and DS of CS was determined by traditional saponiﬁcation method and 1H-NMR, respectively. The solubility of CS was also investigated; the results showed that the higher DS of CS was, the easier CS dissolved in organic solvents. The thermal analysis was measured with DSC, and the results indicated that the glass transition temperature (Tg) and the maximum temperature of thermal decomposition (Tmax) of CS were dependent on DS.
Research on Distribution of Error in CNC Curve Grinding
Authors: Gong Ya Dong , Fan Zhi Guang , Shen Yu Zhuo , Yao Li
Published: April 2011

The grind test is detected curve of the grinding surface roughness of thin in use of three-dimensional contour in this paper, major influence factor in the accuracy of surface roughness is proposed in the analysis based on grinding surface roughness.Trend of the grinding surface roughness is simulated in Matlab. It is expected that best surface roughness can be obtained by selecting the appropriate cutting speed and feed rate for the material pair of workpiece and cutting tool.
Numerical Simulation of Gas Flow Field in the Moving Bed of Corex Melter-Gasifier
Authors: Pan Gang , Liu Xun Liang , Wen Zhi
Published: April 2011

The Corex process, which consists of the upper reduction shaft and the melter-gasifier is an alternative ironmaking process to the blast furnace. The Corex melter-gasifier is a countercurrent reactor to produce liquid iron. Directly reduced iron(DRI), noncoking coal, and other additives are charged to the melter-gasifier at their respective temperature, and O2 is blown through the tuyeres. Moving bed of melter-gasifier is an important zone for reduction of iron oxide and melting of DRI, in which lump coal is a function as skeleton of moving bed replacing coke. A two-dimensional mathematical model was developed for describing gas flowing in the moving bed of Corex melter-gasifier. The gas velocity and pressure distribution were obtained. Further more, the effects of deadman porosity and cohesive zone, burden profile and height of moving bed above tuyere on the gas velocity and pressure distribution were studied.
Damping Capacity of Fe-Ga Alloys
Authors: Ling Fang Mei , Zhu Jie , Heng Li Ji , Xu Gao Xue
Published: April 2011

The damping capacity of Fe-Ga rods and sheets has been studied using a computer-controlled automatic inverted torsion pendulum instruments in a wide temperature range in a series of frequency. The frequency and temperature has different influence on the damping capacity of solidified Fe83Ga17 rods and (Fe83Ga17)97.25Cr2B0.75 sheets. The damping capacity of all specimens increased with frequencies. The solidified Fe-Ga rods showed an obvious low-temperature peak and a potential high-temperature peak with increasing temperature. However, the damping capacity of Fe-Ga sheets kept steady in a wide temperature range and then rapidly increased on further heating above 400°C. Damping capacity of about 0.02 was obtained in both Fe-Ga rods and sheets at temperatures from room temperature to 500°C. Thus, The Fe-Ga alloys are considered to be a class of promising high damping alloys.
Study on Naval Airport Aerial Equipment Distributed Storage System
Authors: Wang Shu Li , Wei Lei , Zhang Hai
Published: April 2011

Naval airport aerial equipment support leads a vital status in aerial equipment support, a key point to support airport aerial equipment is the warehouse, but most existents are single and fixed, survival risk of the warehouse becomes an important threat to combat ability of airplane. Aimed at reducing risk of naval airport aerial equipment warehouse in wartime, a distributed system was given to optimize the naval airport aerial equipment storage solution. This system effects not only on reducing risks in wartime equipments supply, but also on equipment transferring support. Based on analysis of the necessity and feasibility of distributed storage, this paper introduce structure and operation process of the system in detail, and some constructive suggestion was given to naval airport aerial equipments storage.
Research on Dynamic Torque Control Strategy for Parallel Hybrid Electric Vehicle
Authors: Yan Yun Bing , Yan Fu Wu , Du Chang Qing
Published: April 2011

It is necessary for Parallel Hybrid Electric Vehicle (PHEV) to distribute energy between engine and motor and to control state-switch during work. Aimed at keeping the total torque unchanging under state-switch, the dynamic torque control algorithm is put forward, which can be expressed as motor torque compensation for engine after torque pre-distribution, engine speed regulation and dynamic engine torque estimation. Taking Matlab as the platform, the vehicle control simulation model is built, based on which the fundamental control algorithm is verified by simulation testing. The results demonstrate that the dynamic control algorithm can effectively dampen torque fluctuations and ensures power transfer smoothly under various state-switches.
Study on Topology Optimum Design of Baffle of Scraper Conveyer
Authors: Qie Yan Hui , Liu Bo , Wang Xiu Hong , Jia Hai Peng , Li Jian Peng
Published: April 2011

At present the study on the application of the topology optimum design in scraper conveyor is still under development. In this paper the topology optimization based on the homogenization method is applied to the design of the baffle on the scraper conveyer, which can provide a valuable conceptual design scheme for the selection of the baffle pattern. In conjunction with the homogenization theory and Finite Element Method (FEA), the mathematical models for designing the baffle by the minimizing mean compliance are developed in this paper. By applying the topology optimum design to the baffle, the topology optimization based on the homogenization method is proved to be reliable and practical at the conceptual design stage of baffle.
Research on the Best Assessment Subjects for the Environmental Protection Performance of Local Party and Government Officials
Authors: Zhou Jing Kun
Published: April 2011

This paper first of all provides the guiding principles for choosing assessment subjects for the environmental protection performance of local party and government officials: effectiveness, scientificalness and objectivity. Effectiveness includes usefulness, inexpensiveness, and urgency; scientificalness includes professionality, systematicness and representativeness; objectivity includes independence, political rationality and authority. After that, starting from these guiding principles, this paper discusses the process of how to choose the best performance assessment subjects according to the analytical model of stakeholder assessment subjects. And then characteristics of potential assessment subjects for the environmental protection performance of local party and government officials are analyzed. At last, through the analytical model of stakeholder assessment subjects and characteristics of potential assessment subjects for the environmental protection performance of local party and government officials, this paper makes a relative analysis of the best assessment subjects for the environmental protection performance of local party and government officials, and gets a conclusion that professional assessment institutions are the best choice.
Study on Quality Problem Information Classification Using ODC Method
Authors: Wang Zhao Wei , Zhou Jian , Liu Jian
Published: April 2011

Aiming at the difficulty in quality problem character information classification, the ODC (orthogonal defects classification) method is introduced. Abide by the discipline of ODC; the quality problem character information is classified into four orthogonal groups. And the character information of each group is analyzed.
Thermomecanical Response of LNG Concrete Tank to Cryogenic Temperatures
Authors: Dahmani Lahlou , MEHADDENE Rachid
Published: April 2011

In this paper are illustrated the principal aspects connected with the numerical evaluation of thermal stress induced by LNG (liquefied natural gas) in a concrete tank. In order to investigate the thermal induced tensile stresses, the ANSYS finite element code has been employed for performing a sequential, non linear, transient thermal-structural analysis, taking into account the thermal dependant properties of the concrete such as thermal conductivity and specific heat. Temperature distribution data of thermal analysis is required in the coupled field analysis finally to obtain and analyze thermal stresses.
The Synthesis of VACNTs Grown on MgxZn1-xO (0< x <0.3) Template
Authors: Muhamad Salina , Abu Bakar Suriani , Ahmad Rafidah , Ahmad Anuar , Siran Yosri M. , Rejab Syahril Anuar M. , Asis Ahmad Jaril , Tahirruddin Syawaluddin , Abdullah Saifollah , Rusop Mohamad
Published: April 2011

In this study, MgxZn1-xO thin film with x varied from 0 to 0.3 was deposited on silicon with the orientation of [1 0 0] using the sol-gel method and spin coating technique. The thin film was annealed at 550°C before being used as a template to grow vertically aligned carbon nanotubes (VACNTs). Field emission scanning electron microscopy (FESEM) indicates that the top view of VACNTs’ topography are very similar to the topography of the template used, MgxZn1-xO thin film. When the value of x increased, the grain size of the template becomes larger and rougher, which were also true with the VACNTs. The electrical properties were measured using IV measurement system, which indicates that the conductivity of the VACNTs is directly proportional to the grain size of the template. Raman spectroscopy was used to inspect the crystal orientation.
Experimental Investigation of Gas-Heavy Oil Molecular Diffusion Coefficient in Porous Media: Experimental Results for CO2 in Iranian Crudes
Authors: Mirjordavi Navid , Kazemeini M. , Kharrat R. , Ghazanfari M.H. , Salehi A.
Published: April 2011

Molecular diffusion of gases in crude oils plays a crucial role in several oil recovery processes especially in cold-based production process. However, experimental data concerning CO2 diffusivity in heavy oils due to the tedious nature of diffusivity measurements are relatively rare in the open literature. In this work, a comprehensive experimental investigation of the effective molecular diffusion determination of CO2-heavy oil systems in homogeneous porous media was studied. The so-called pressure decay method was applied to measure the molecular diffusivity of carbon dioxide in heavy oil. Furthermore, effect of various parameters such as initial pressure, temperature and porous media on molecular diffusion coefficient have been analyzed and based upon experimental results, a new mathematical correlation for prediction of CO2-heavy oil molecular diffusion coefficient in presence of porous medium as a function of temperature was proposed.
Growth of Multi-Shaped Zinc Oxide Nanostructures Using C-Axis Oriented Zinc Oxide Thin Film as a Seeded Catalyst via Hydrothermal Aqueous Chemical Growth Method
Authors: Mamat Mohamad Hafiz , Khusaimi Zuraida , Rusop Mohamad Mahmood
Published: April 2011

Zinc oxide (ZnO) nanostructures with different kind of morphologies were synthesized on glass substrates via the hydrothermal aqueous chemical growth method utilizing c-axis oriented ZnO thin film as seeded catalyst. By preparing ZnO thin film at different molar concentrations between 0.2~1.0 M, oval shaped ZnO nanostructures mixed with ZnO nanowires and rod shaped ZnO nanostructures mixed with ZnO nanowires were produced after immersion process into 0.0002 M zinc nitrate solution for 24 hour. The XRD spectra show synthesized ZnO nanostructures were ZnO hexagonal wurtzite crystalline. The photoluminescence (PL) measurement indicates the luminescences of the samples were depending on the shapes of ZnO nanostructure.
Optical Properties of Nanostructured Zinc Oxides Deposited on Silicon Substrates
Authors: Mamat Mohamad Hafiz , Khusaimi Zuraida , Rusop Mohamad Mahmood
Published: April 2011

Nanostructured zinc oxide (ZnO) thin films were prepared through sol-gel method and spin-coating technique. ZnO thin films then were annealed at temperature of 350°C, 400°C, 450°C and 500°C. The thin films were characterized using field emission scanning electron microscope (FESEM), UV-VIS-NIR spectrophotometer and photoluminescence (PL) spectrofluorometer for morphology and optical properties study. The morphology study indicates that the particle size of ZnO increased with annealing temperatures. All thin films are optically transparent (~ 80 % in transmittance) in the visible light-NIR region. PL spectra reveal improved UV emission with annealing temperatures up to 500°C.
Extraction of Useful Food and Cosmetic Ingredients of Vegetable Origin
Authors: Vázquez da Silva M. , Delgado João M.P.Q.
Published: April 2011

In the present work, three different mathematical models that can be applied to simulate the supercritical fluid extraction from herbaceous matrices were studied: Single-Sphere Model I (SS I), Single-Sphere Model II (SS II) and Characteristic Time Model (CTM). It was tested and compared the agreement between models results and available experimental data reported in literature.