bluuebunny/crossref_metadata_2025 huggingface dataset:
Process Characterization of Wet Etching for High Aspect Ratio Microneedles Development
Authors: Aziz Norazreen Abd , Buyong Muhamad Ramdzan , Majlis Burhanuddin Yeop
Published: September 2009

Research on microneedles has been increasing rapidly as to overcome the drawbacks of conventional needle which can results in painful during injection, tissue damage and skin infection at the injected site. This paper presents characterization process of wet isotropic etch for solid microneedles array development. This approach utilizes HNA etchant to build the outer shape of solid microneedles. Works has been carried out to investigate the isotropic etching behavior of HNA in different temperature ranging from 20 to 50 degrees, various agitation rate ranging from 0 rpm to 450 rpm and on the various window size ranging from 100 μm to 500 μm. Characterization on those factor, determine the effect of vertical and lateral etch rate variations, surface quality and the geometry obtained. The experimental responses of vertical etch rate, lateral etch rate and high aspect ratio reported. The obtained etching properties will be applied to develop recipes to fabricate outer shape of solid microneedles’ tip.
Photothermal Imaging (PTI) System for the Imaging of Gold Nano-Particles and Cellular Organelles
Authors: Wong Chi Lok , Chen George C.K. , Kiat Teu Choon , Vasudevan Srivathsan , Anh Pham Thuy , Puhan Niladri Bihari , Andika Marta , Agarwal Shuchi , Lin Zhi Ping , Peng Chen
Published: September 2009

Photo-thermal imaging (PTI) is an imaging technique that can provide a resolution exceeding the diffraction limit. The theoretical resolution limit is less than 1 nm, therefore it is particularly suited to analyse particles in nano-size targets. It is also a non-labelling, high temporal resolution technique that can be conducted in a normal live cell environment. In this paper, a PT imaging microscopy system has been demonstrated and the integrity of the system is verified through a series of experiments on different samples, including red polystyrene bead and carbon nano-tube. The PTI technique can find further applications in biology studies for the visualization of cell organelles and apoptosis studies.
Dynamic Liquid Optical Splitters and Interferometers Integrated into Micro-Fluidic-Systems
Authors: Yang Yi , Liu Ai Qun
Published: September 2009

As the field of Micro-Fluidic-Systems (MFS) is still at it early stage of development, only some simple optical devices such as liquid waveguide and liquid optical switches have been reported. The lack of in-depth analysis makes some novel photonic phenomena unexplained and uninvestigated in MFS. Solutions to these problems require a lot of imagination and ingenuity. In this paper, dynamic liquid optical splitters and interferometers have been demonstrated by diffusion according to flow rates are reported. In the case of the Y splitters, light from a single source can be split into two directions with angle-controlled dynamic. To the interferometers, light from a single source can be split and then combined to interference. The lengths of the interferometers can be controlled from via control of diffusion coefficient and flow rate. It implies that the Micro-Photonic-Fluidic –Systems may establish a new branches to MFS and has potential applications in biological, chemical and medical solution detectors.
Flows in Microchannels and Cavities – Visco-Elasticity, Faradaic Charging and Surface Roughness Effects
Authors: Lam Yee Cheong
Published: September 2009

Two phenomena for flows in microchannels, namely visco-elastic instability and Faradaic charging effects, are discussed. Aqueous solutions, which do not exhibit elastic behaviors, will behave visco-elastically with the addition of a small amount of polymers. Visco-elastic flow instability which promote mixing has been observed in the flow of these visco-elastic solutions through a constriction in microchannels. In addition, we recently show experimentally the existance of Faradaic charging in AC-electrokinetic (ACEK) flow. Lastly, surface roughness effects in micro- plastic injection molding are highlighted. The micro-injection molding process involves the flow of polymer melt in micro-cavities. Our recent investigations demonstrate that the flow model for macro-cavities could be employed satisfactorily to simulate the flow in micro-cavities if roughness effects are considered in an appropriate manner.
Full-Scale Numerical Simulation of Plasma-Sprayed Functionally Gradient Materials
Authors: Wang Fu Chi , Fan Qun Bo , Wang Lu , Wang Quan Sheng , Ma Zhuang
Published: September 2009

To develop novel and advanced thermal barrier coatings, full-scale numerical simulation of plasma-sprayed functionally gradient materials is conducted in this paper, including the prediction of basic parameters at the nozzle exit, simulation of three dimensional simulation of the plasma jet, modeling of the interaction between the plasma jet and the particles, calculation of flight trajectories and temperature history of flying metal and ceramic particles, the interaction between the molten particles and the substrate, as well as the deposition process of the coatings. Various complex phenomena, such as turbulent effects with chemical reactions in the plasma jet, dispersion status of the particles onto the substrate, and the composition distribution of the functionally gradient materials, are fully taken into account. The numerical simulation results are found to be in good agreement with experimental evidence.
Performance of TC4 Titanium Alloys Coated with Different Sol
Authors: Liu Hui Cong , Zhu Li Qun , Li Wei Ping
Published: September 2009

Titanium alloys has been widely used in many fields, while in high temperature and rigorous corrosive environment, it is very necessary to do some work on the surface of titanium alloys to satisfy with application purpose. In this paper, four kinds of sol film were prepared on titanium alloys with and without anodic oxidation film. The prepared sol included Al2O3, Al2O3-ZrO2 and doped sol by adding additive into them respectively. The film thickness, high temperature oxidation resistance and corrosion resistance after high temperature oxidation for some time were investigated. The results show that the sol film obtained on the anodic oxidation film of titanium alloys is thicker than that without anodic oxidation film. Compared with the other three kinds of film, the doped Al2O3-ZrO2 sol film has the best high temperature oxidation resistance and corrosion resistance due to insulation effect of the sol film, and the composition of additive and zirconic.
Estimation of Dressing Effects in Chemical Mechanical Polishing with Sorts of Diamond Dressers
Authors: Chen Kuen Ren , Young Hong Tsu
Published: September 2009

Chemical mechanical polishing (CMP) is a semiconductor process that is used to achieve global planarization. To maintain the stability and the throughput of CMP, the polishing pad needs to be dressed by a diamond dresser. By calculating the distribution of the scratch numbers of diamond grits in the pad, the effect of dressing can be estimated and the pad profile can be predicted. All the parameters of dressing motion were taken into account. The target equipment of this study is Mirra Mesa, which is manufactured by Applied Materials. Different types of dressers, including ring-types and full-type, different pitches and arrangements are used in CMP process. Each of them was simulated in this study. The diamond pitch is relative to the number of diamonds and the scale of the total scratch time, but does not affect the profile of the scratch time. Regular or random arrangement makes no difference in the profile of the scratch times. The width of the ring influences the number of diamonds and the scale of the total counts while the profiles remain similar.
Research on Electrical Discharge Truing for Precision Profile Grinding with Cast Iron-Bonded Diamond Wheel
Authors: Li Wei , Geng Bao Gong , Song Zhi Yang , Zheng Hai Hui
Published: September 2009

In this paper, a precise profile ELID grinding with Electrical Discharge Truing(EDT) has been introduced, and some experiments for efficient and precision EDT process with cast iron-bonded diamond wheel have been carried out with four types of medium: mist, water, pressure air, air, furthermore some machining parameters e.g. electric current, electric voltage have been discussed in detail. For analyzing of the accuracy of EDT process with cast-iron bonded diamond wheel, a profile measurement method with software of MATLAB was used for analyzing of the profiles of cast-iron-bonded diamond wheel and electrode. It can be found that the electrode’s profile can be kept with the consistent designed profile, and the grinding wheel with the designed profile has been got by the appropriate EDT process. Therefore the higher efficiency and precision EDT process can be achieved by the appropriate EDT machining parameters.
A Study of Thermal-Chemical Polishing for CVD Diamond Thin Films
Authors: Tso Pei Lum , Wang Thing Ming
Published: September 2009

Chemical vapor deposition (CVD) diamond thin films are widely used in modern industries. However, due to the nature of polycrystalline, thin films are required to be polished in the final process to increase its surface quality. Thermal-chemical polishing is known for its less processing time and low cost. In this paper, the experiments are carried out to observe the effect of processing conditions such as temperature, rotational speed, polishing pressure, and substrate material on the surface roughness and on the material removal rate of the chemical vapor deposition diamond (CVDD). At the same time, the processing mechanism for this thermal-chemical polishing is investigated, and a polishing model is built for comparison with the experiment results. The results show that the material removal rate is affected mainly by the diffusing rate in the Fe-C polishing system. By using the model, the approximate value of material removal rate can be calculated according to the polishing temperature.
Influence of Abrasive on Planarization Polishing with the Tiny-Grinding Wheel Cluster Based on the Magnetorheological Effect
Authors: Yan Qiu Sheng , Yang Yong , Lu Jia Bin , Gao Wei Qiang
Published: September 2009

Experiments were conducted to polish optical glass with the magnetorheological (MR) effect-based tiny-grinding wheel cluster, and the influences of abrasive material, particle size and content on the material removal rate and surface roughness are investigated. The experimental results indicate that: the higher the hardness of abrasives, the higher the material removal rate, but the abrasives with lower hardness can obtain lower surface roughness. The better polishing quality of the workpiece can be obtained when the particle size of abrasives is similar to the particle size of magnetic particles. Moreover, the content of abrasives has an optimum value, and the material removal rate and the surface quality can not be improved further when the content of abrasives exceeds the optimum value. On the basis of above, the material removal model of the new planarization polishing technique is presented.
An Analytical Solution for Parameter Selection for Polishing Spherical Surfaces
Authors: Li H.F. , Bao R.H. , Zhang Liang Chi
Published: September 2009

This paper establishes an analytical solution for describing the trajectories of abrasives in polishing spherical surfaces when the motions of the tool and workpiece involve three independent angular velocities. As an example of its applications, the solution is used to show the effect of angular velocities on the trajectory coverage uniformity on a spherical surface – a key aspect for the control of a uniform material removal in a polishing operation. This solution provides a theoretical tool for the parameter selection of such machining processes.
Necessary Cutting Energy in Abrasive Waterjet Machining
Authors: Pi Vu Ngoc , Tuan Nguyen Quoc
Published: September 2009

This paper introduces a new study on the modeling of AWJ necessary cutting energy. In the study, a model for prediction of the necessary cutting energy is proposed by combining physical-mathematical models and experimental methods. The effects of various jet parameters as well as the effects of the abrasive size, abrasive material and the effect of work material on the necessary cutting energy are taken into account.
Abrasive Technology in Ceramic Restorative Dentistry
Authors: Yin Ling
Published: September 2009

The application of abrasive technology in dentistry dates from 7000–9000 years. How does this ancient technology affect our modern society where the elderly population needs extensive dental care and ageing well and ageing productively is our first priority? Many patients prefer tooth-colored, all ceramics restorations fabricated by dental CAD/CAM systems for reasons of esthetics, biocompatibility and high efficiency. In spite of the advantages of all-ceramic restorations, ceramic prostheses have not always performed as predicted or desired. Catastrophic fracture has been the most frequently reported reason for failure of all-ceramic restorations. This paper gives a brief review on abrasive technology in ceramic restorative dentistry to highlight problems to be solved by our abrasive technology community.
Optimization of Coated SiC Belt Grinding of Alumina Ceramics
Authors: Kennedy Xavier , Gowri S.
Published: September 2009

Advanced structural ceramics have been increasingly used in automotive, aerospace, military, medical and other applications due to their high temperature strength, low density, thermal and chemical stability. However, the Grinding of advanced ceramics such as alumina is difficult due to its low fracture toughness and sensitivity to cracking, high hardness and brittleness. In this paper, surface integrity and material removal mechanisms of Alumina ceramics ground with SiC abrasive belts, have been investigated. The surface damage have been studied with scanning electron microscope (SEM). The significance of grinding parameters on the responses was evaluated using Signal to Noise ratios.This research links the surface roughness and surface damages to grinding parameters. The optimum levels for maximum material removal and surface roughness been discussed.
Determination of Elastic Modulus of Thin Coating Materials Using Nanoindentation and Finite Element Analysis
Authors: Liu Sheng , Gu Yuan Tong , Huang Han
Published: September 2009

A deconvolution method that combines nanoindentation and finite element analysis was developed to determine elastic modulus of thin coating layer in a coating-substrate bilayer system. In this method, the nanoindentation experiments were conducted to obtain the modulus of both the bilayer system and the substrate. The finite element analysis was then applied to deconvolve the elastic modulus of the coating. The results demonstrated that the elastic modulus obtained using the developed method was in good agreement with that reported in literature.
Modeling and Analysis of Effects of Machine Tool Stiffness and Cutting Path Density on Infeed Surface Grinding of Silicon Wafer
Authors: Zhou Li Bo , Mitsuta Takahito , Shimizu Jun , Tajima Takuji
Published: September 2009

Many models [1-3] have been proposed to study the infeed grinding of Si wafers and to understand its effects on the surface generation. However, most exiting models are based on 2D/3D kinematical analysis of the wheel or its cutting edges, thus unable to suggest the behavior at the interface of wheel/substrate including effects of the elastic deformation and the cutting path density. In this paper, a new grinding model of capable to incorporate the machine tool stiffness and the substrate contact rigidity has been developed. By taking the effect of cutting path density into account, this model is able to give a better explanation of interference between the cutting edge and substrate, and the geometrical profile generated in an infeed grinding scheme.
Effects of Machining Parameters on Surface Roughness in Microturning of OFHC Copper
Authors: Ranjith kumar P. , Gowri S.
Published: September 2009

Miniature parts with high accuracy and precision are increasingly in demand for various industries. Microturning is a process for fabrication of such miniaturized parts with features that range from tens of micrometres to a few millimetres. In this present study commercially available Oxygen Free High Conductivity (OFHC) copper rods have been microturned using cermet inserts of 0.1mm nose radius. The effects of machining parameters on the surface generated have been discussed. Scanning electron microscope images of worn out inserts and machined surfaces are analysed to ascertain the wear mechanism and study the nature of the surface generated.
Experiment Research on the Temperature Field and Thermal Error Distribution of NC Grinding Machine
Authors: Gong Ya Dong , Bai Yan Guang , Liu Yue Ming , Qiu Jian
Published: September 2009

With the help of the infrared camera temperature measurement technology, the systemic theoretical analysis and experimental research for temperature field and thermal error distribution in NC grinding machine is provided. Two different situations for temperature field and thermal error distribution are respectively measured while the free and loaded grinding by the new measurement method. The mathematical model of thermal error is built, and it shows that the actual error and the forecasted error from thermal error mathematical model have good comparability.
Test of Focusing and Superposition for Variable Strength Activation of Coolant in Precision Machining
Authors: Zhang Y. , Zhou S. , Gao Y.
Published: September 2009

To allow better machining heat transfer through mist evaporation, a new active cooling method is proposed. It is based on variable strength activation of coolant together with active cooling. A key issue in the proposed method is the use of multiple actuators of high frequency vibration for extra strength increase. This will rely on the idea of focusing and superposition. In this project, experimental tests were conducted to test the idea for the proposed variable strength activation of coolant in precision machining. Experimental test results show that the effects of ejection distance de on the vibration sensor output amplitude Aa and output frequency fa are not significant. The output amplitude Aa has a linear relationship with the number of actuator na. The effects of na on fa is not obvious. Based on the results, the idea of using multiple actuators for focusing and constructive superposition in variable strength activation is confirmed.
Purification Effect of Micro Bubble Coolant
Authors: Ninomiya Shinichi , Iwai Manabu , Shimizu Toshiharu , Uematsu Tetsutaro , Suzuki Kiyoshi
Published: September 2009

The authors have proposed a new coolant named “micro bubble coolant” in which micro bubbles (20-50µm in diameter) are included. In the previous study, it was clarified that the tool life is improved by applying this new coolant to various machining such as boring, turning and grinding. This paper deals with purification effect of the micro bubble coolant. It has been found from the experiments that bacteria which cause putrefaction of the conventional water soluble coolant are eliminated by generating micro bubbles in the coolant. It has also been clarified that the micro bubble coolant isolates minute machined chips and machine oil from the coolant.
Development and Application of CSD Diamond Abrasives
Authors: Wang Qin Sheng , Liang Cun , Zhao Qing Guo
Published: September 2009

. Traditional diamond grits used for making resin bonded abrasives are monocrystalline in acicular shape and with smooth surface, so they are easy to fall off prematurely during grinding, the use effect is not good. Taking the powder graphite and the iron-base alloy catalyst as the raw material by adopting a new indirect heating craft, under the high pressure and high temperature conditions within cubic press, this project developed a new variety of diamond -- CSD abrasive with crumb structure. They have equi-axed shape and rough surface. It has been proved that the abrasive wheels made with CSD diamond have self-sharpening characteristics and high bondability. The grinding efficiency and service life of the abrasive wheels made with CSD can be doubled.
Optimization of Cutting Edge Truncation Depth for Ultrasonically Assisted Grinding to Finish Mirror Surface
Authors: Hara Keisuke , Isobe Hiromi , Kyusojin Akira
Published: September 2009

High precision mold grinding technique to obtain mirror surface is required which realizes minimization or omission of final polishing by skilled workers. In the previous reports, ultrasonic diamond grinding experiments were carried out to confirm ultrasonic oscillation effect for die steel face grinding. Smooth and glossy surfaces were obtained successfully and little abrasive worn out was found. In the above techniques require cutting edge truncation because the cutting edge shape of a tool affects the ground surface resulting from transcription of cutting edge. This paper describes optimization techniques for the cutting edge truncation of diamond electroplated tools which are used in ultrasonically assisted grinding. Experiments were carried out to confirm truncation effects on the ground surface and grinding force. It was confirmed that roughness was proportional to inverse of thrust force. Minimum roughness in grinding conditions were estimated from the proportional diagrams. The minimum roughness shows limit of roughness on an each grinding condition.
Influencing Factors of 1Cr13 SSCC for Oil & Gas Wellhead
Authors: Pei Jun Feng , Zhang Gui Xin , Yin Shun Shi , Deng Xue Feng
Published: September 2009

With the exploration of oil-gas field developing, more and more oil-gas well contain H2S, hydrogen sulfide stress corrosion has serious effect on production and restrict oil field development. With the applications of 1Cr13 steel in oil & gas wellhead, it is urgent to research hydrogen sulfide stress corrosion cracking (SSCC) properties in high-strength under the simulation condition of production. The tensile test under constant load and slow strain rate test (SSRT) were adopted to analyze the behaviors of 1Cr13 steel with orthogonal test under saturated H2S solution which included carbon dioxide under a partial pressure and its sample fracture was observed with SEM (Scanning Electron Microscope). Constant load tensile test is one of the first recognized by NACE to assess the performance of metallic materials against SSC approach under tensile stress in the aqueous solution which was in low pH value and H2S was saturated. Through the research above the mechanism of stress corrosion and the environmental factors that influence stress corrosion were investigated. The experimental results shown that the effects of environmental factors on SCC (Stress Corrosion Cracking) sensitivity of materials are in the following order: temperature effect > solution pH effect > chloride ion concentration effect, and 1Cr13 material has a better corrosion resistance for H2S and CO2 conditions under a certain stress so it can be proposed as the material of value for oil & gas wellhead. Through SEM it can be seen that the fracture is belonged to brittle fracture. The lattice bonding force is destroyed by hydrogen into the material that gathered in the certain crystal face and the material transform from plastic to brittleness, the material is failed, and SCC occurred.
Adhesion and Corrosion Resistance Properties of TiC/Ti(CN)/TiN Multilayer CVD Coatings on 42CrMo Steels
Authors: Zhang Jin , Xue Qi , Cheng Xiao Wei , Zhang Chun Mei , Li Song Xia
Published: September 2009

The TiC/Ti(CN)/TiN multilayer coatings were deposited on 42CrMo steel by chemical vapor deposition (CVD) method. The fracture morphology,structure,microhardness and adhesion of the coatings were analyzed. The immersion test in simulant solution with H2S,CO2 at 100°C and electrochemistry test in 20wt% H2SO4 at room temperture were applied to investigate the corrosion resistance of the multilayer films.The results reveal that the multilayer coatings can offer 42CrMo steel higher corrosion resistance,especially the immersion corrosion test.The corrosion rate of the samples coated with CVD multilayer films is reduced more 70 times than that of the uncoated and samples by quenching-polishing-quenching (QPQ) treat.
The Improvement of Durability of Marine Wood with Polymer and its Mechanism
Authors: Li Yong Feng , Liu Yi Xing , Wang Xiang Ming , Li Xiu Rong
Published: September 2009

In order to improve the durability of marine wood against the long-term marine corrosion, the study explores to use two bifunctional reagents, maleic anhydride (Man) and glycidyl methacrylate(GMA), to react with wood by impregnating them into the porous structure of wood and further initiating them to polymerize with an initiator, AIBN, through a heat process. After the above modification, the durability of the marine wood treated with polymer was tested, and its mechanism was further analyzed as well. The testing results of the durability show that the acid resistance, the alkali resistance, the decay resistance against marine borers and the dimensional stability of the treated wood increases by 2.02 times, 12.39 times, 4.96 times and 3 times over untreated wood, respectively; and its Anti Swelling Efficiency (ASE) for dimensional stability reaches 53%, which almost equals the value of the wood treated by PEG-1500 under the same condition, while its leachability resistance is greatly higher than wood treated by PEG-1500. The analysis result with FTIR indicates that Man and GMA both react with wood, and Man reacts with the hydroxyl group of wood cell walls by its anhydride group, and GMA polymerizes in the porous structure of wood. The charactering result with SEM reveals that the resultant polymer fills in wood cell lumina as a solid form, which contacts tightly the wood cell walls without obvious gaps. The greatly reducing amount of hydroxyl groups after the reaction and the heavy jamming channels for water and marine borers approaching to wood cell walls both contribute to the improving durability of the modified wood.
Low Driving Voltage Aluminum Alloy Anode for Cathodic Protection of High Strength Steel
Authors: Ma L. , Li K. , Yan Y. , Hou B.
Published: September 2009

The present work was focus on developing low driving voltage sacrificial anode for high strength steels. Taking the zinc and bismuth as main active elements, we designed and prepared several aluminum alloy anodes and investigated their electrochemical performance by galvanic test in natural seawater. The results showed that the anode exhibits high performance with 0.55wt.% Zn and 0.5wt.% Bi as the alloying elements. Its potential is varied from -800mV to -820mV, the current capacity is 2565 Ahr/kg, and the dissolution is homogeneous. We concluded that Al-0.55%Zn-0.5%Bi alloy anode can be used to high strength steel for corrosion protection. The microstructures of the anodes were observed by optical microscope, the result proposed that the uniform dissolution morphology of Al-0.55%Zn-0.5%Bi anode is due to its fine grain size.
Corrosion Inhibition of Dissymmetric Bis-Quaternary Ammonium with Imidazoline Ring on Q235 Steel in 1.0 mol•L-1 Hydrochloric Acid Solution
Authors: Jiang Bin , Du Min , Zhang Jing , Sun Zhao Dong
Published: September 2009

Dissymmetric bis-quaternary ammonium with imidazoline ring was evaluated for corrosion inhibition efficiency against Q235 steel in 1.0mol•L-1hydrochloric acid solution at room temperature (298K) by gravimetric method, potentiodynamic polarization, electrochemical impedance spect- rum(EIS) and quantum chemical calculation. The results of mass loss and polarization data showed the compound acted as a very good mix-up inhibitor for Q235 steel in 1.0mol•L-1hydrochloric acid solution. EIS results showed that the associated values of the charge transfer resistance (Rct) increase by increasing the additive concentrations and immersing time whereas the associated values of double layer capacitance (Cdl) decrease. These changes in the impedance parameters (Rct and Cdl) are indicative of adsorption of the compound on Q235 steel surface leading to the formation of a protective film. The obtained correlations and Quantum chemical calculations conclusions agree well with the experimental results.
Structural Design and Performance Testing of Flexible Fabric Keyboard Switch
Authors: Zhang Mei Ling , Wang Rui
Published: September 2009

Flexible fabric keyboard is a field of smart textile. It can overcome traditional horniness keyboard can’t be foldable and washing. Because conventional keyboard’s switch is matrix circuit, two conductive layers are not touchable due to action of a middle insulating layer in relaxing. When the key is pressed, two conductive layers contact and form electric current. In this laboratory study there are two kinds of methods adopted, for example, Three-layer Fabric Weaved Separately (TFWS) and Three-layer Fabric Shaped Once(TFSO). They were significantly different in weaving methods, fabric structure and weaving efficiency. Three species were designed for every method. Although Connection Ratio (CR) of 6×6 and 8×8 in TFWS was 100%, TFWS took many repeating and complex processes. Much time and labor were seriously spent so that weaving efficiency was consumedly reduced. However, if making use of Three-layer Fabric Shaped Once(TFSO) which adopted three dimensional weaving method, only one procedure was required for fabric keyboard matrix circuit. The three dimensional weaving fabric consisted of support part and orifice part. When pressed in the key position, the top and down layer of the orifice part can contact with each other. Then the circuit can connect. When the applied force was released, the top and down layer can return to primary position due to the action of the support part. TFSO didn’t require many repetitive and complex courses. Therefore the weaving efficiency can be greatly increased. To be more importantly, CR of 16 wefts in TFSO was comparatively not bad among in three species of TFSO. When considering all six species for two methods together, 16 wefts in TFSO appears to provide the most suitable fabric for flexible fabric keyboard matrix circuit as a result of shaping once, high weaving efficiency and 100% CR. These findings may assist in recommendations regarding the further development of flexible fabric keyboard.
Calculation of Flexural Capacity of Steel Reinforced Concrete Beams Strengthened with FRP
Authors: Liang Jiong Feng , Yang Ze Ping , Yan Lan Lan
Published: September 2009

Based on earlier theoretical works on RC beams ,the mechanical properties of steel reinforced concrete beams strengthened with FRP(fiber reinforce polymer) are further investigated theoretically including theirs failure mechanism and loadability. According to the design method of reinforced concrete beam strengthened with FRP, steel reinforced concrete beam strengthened with FRP mainly can have three kinds of destruction patterns: the first case is the tensile steel yield, the tensile shaped steel yield, the FRP are put off, the compressive zone’s concrete has not crushed; the second case is the tensile steel yield, the tensile shaped steel yield, the FRP are put off; the compressive zone’s concrete has crushed; the last case is the tensile steel yield, the tensile shaped steel yield, the FRP are not put off, the compressive zone’s concrete has crushed. The second case is discussed in this paper.Based on the different position of middle axle and steel, steel concrete beams strengthened with FRP include: middle axle through the steel web, and not through the steel and just in steel compression flange . Aim at these three kind of situations, the stress are analysed. According to the stress patterns of steel reinforced concrete beams strengthened with FRP and different position between neutral axis and steel, the discriminant formula of the boundary destroys and the formula of cross-section flexural capacity calculation are put forward by using limit equilibrium theory.The formula is expressed clearly, simple and easy to use.The depth of compressive region is given in view of different failure types.
Stress Corrosion of High Performance Hybrid Fibers Reinforced Expansive Concrete Exposed to Magnesium Sulfate Solution
Authors: Yang Li Ming , Yu Hongfa , Ma Haiyan
Published: September 2009

Deterioration of fly ash concrete (FAC), high performance concrete (HPC), and high performance hybrid fibers reinforced expansive concrete (HPHFREC) subjected to combined action of flexural load and 5% magnesium sulfate solution is investigated. The change of dynamic modulus of elasticity (DME) was monitored and recorded as to observe the corrosion of concrete specimens in magnesium sulfate environment. Results show that in the initial exposure stage, the relative dynamic modulus of elasticity (RDME) of concretes increase steadily as a result of the reinforced effect of flexural load and nucleation of attack products, consequently the microstructure is compacted and the strength of the concretes is enhanced in some extent. As for the later corrosion proceed, the interior cracks occurred and the flexural load accelerated the degradation of concrete. HPC demonstrated good corrosion resistance when it was exposed to only magnesium sulfate solution, and HPHFREC showed the best stress corrosion resistance when it was subjected to combined action of magnesium sulfate solution and flexural load.
Atomic Simulation of the Bending Deformation of a Single-Crystal Simply Supported Nano-Beam
Authors: Ni Wen Bin , Zhao Jian Wei , Liu Yun Hong , Wang Feng Ying , Yin Xing
Published: September 2009

Advanced fabrication techniques to miniaturize electromechanical systems have brought us into the regime of nanoelectromechanical systems (NEMS). Understanding the mechanical properties of NEMS components is of fundamental importance in the operation of these devices. In this paper, we have reported the deformation behavior of a single-crystal simply supported nano-beam under the uniformly distributed load. By using the molecular dynamics simulation, we have investigated the influence of span the nano-beam on the bending characters. Due to surface effect, the nano-beam shows a different behavior under the uniformly distributed load.
Theory Study of the Geometrical Isomerism Influence on Hole-Transport Material’s Residual Potential of Organic Photoconductive
Authors: Jing You , Wang Shi Rong , Li Xiang Gao
Published: September 2009

Residual potential is a very important performance index of organic photoconductor (OPC). At present, research shows that the purity of charge transport material will seriously influence residual potential of OPC. But in past research we found that some OPC used charge transport material with very high purity still has very high residual potential. With quantum calculation and x-ray diffraction we found that some materials are optical isomer and some have cis-trans isomerism. So in order to improve performance of OPC we should separate isomerism.
Simulation on Uniaxial-Tension Behavior of NiTi Shape Memory Alloy Films
Authors: Sun Shuang Shuang , Dong Jing
Published: September 2009

Based on experimental results reported in the reference, Liang-Rogers’ constitutive model for SMA is used to simulate the stress-strain curves of NiTi shape memory alloy films under uniaxial tension with isothermal conditions. The effects of film compositions and temperature on the tensile behavior of NiTi shape memory alloy films are discussed. By comparing the simulation results with the experimental results, it is found that the simulation curves agree basically with the experimental curves except that the phase-transformation regions are wider in the simulation curves. This demonstrates that the Liang-Rogers’ model can be used to predict the thermomechanical behavior of shape memory alloy films roughly. This study provides some theoretical foundation for the quantitative description and prediction of the actuation mechanism when shape memory alloy films are used as micro-actuators.
Process Analysis and Numerical Simulation of Equal Channel Angular Pressing and Torsion (ECAPT)
Authors: Li Yong Zhi , Xue Ke Min , Li Ping
Published: September 2009

Severe Plastic Deformation (SPD) methods are currently hot research techniques of preparation of bulk ultrafine-grained materials.Among the various SPD methods, ECAP (Equal Channel Angular Pressing) and TE (Twist Extrusion) have respective advantages and disadvantages and there have many questions in this research area at home and abroad although they are representative and rapidly developing and the promising ones.ECAPT, ECAP organic integrated with TE, was introduced for the frist time and the process principle and features were set forth in this study. The numerical simulation of the process was further analyzed with DEFORM-3D software.The results show that there have two main deformation zones in forming process of ECAPT during a single pass, and vertical and horizontal shear deformation have been taken place in workpiece and the value of effective strain is equivalent to accumulated deformation of ECAP and TE after one pass; And the peak and average value of effective strain when ECAPT are far greater than those of effective strain during the process of ECAP or TE. It is confirmed that there have more effective strain rate and more stronger severe plastic deformation during the process of ECAPT,and it improves the ability of material’s plastic deformation.
Experimental Researches on the Mechanical Properties of Three Dimensional Multidirectional Braided Composites
Authors: Sun Ying , Li Jia Lu , Chen Li , Shao Ying
Published: September 2009

This paper investigated the mechanical properties and the relationships between fiber architecture and the composites properties of three-dimensional multidirectional braided composites made of Toray@T700 carbon fiber impregnated with TDE 86# epoxy resin using RTM. The strength and stiffness properties measured here include tension, compression, flexure and short beam shear, all of these in both the longitudinal and transverse directions. It is found that the 3D six-directional braided composites with 55 % fiber volume fraction and 25°surface braiding angle represent quasi-isotropic in-plane elastic behaviors due to their symmetric, intertwined architecture and unidirectional reinforcements in both the longitudinal and transverse directions. Compared with the tension strength and modulus, those for compressions in the same directions descend near 40% and 10% respectively. The cut-edge on the width destroys the integrity of microstructure and inevitably cuts down the carrying capacity of composites under the longitudinal tension.
Electronic Structure and Optical Properties of Non-Metals (N, F, P, Cl, S)-Doped Cubic NaTaO3 by Density Functional Theory
Authors: Han Pei Lin , Wang Xiao Jing , Zhao Yan Hong , Tang Chang He
Published: September 2009

Electronic structure and optical properties of non-metals (N, S, F, P, Cl) -doped cubic NaTaO3 were investigated systematically by density functional theory (DFT). The results showed that the substitution of (N, S, P, Cl) for O in NaTaO3 was effective in narrowing the band-gap relative to the F-doped NaTaO3. The larger red shift of the absorption edge and the higher visible light absorption at about 520 nm were found for the (N and P)-doped NaTaO3. The excitation from the impurity states to the conduction band may account for the red shift of the absorption edge in an electron-deficiency non-metal doped NaTaO3. The obvious absorption in the visible light region for (N and P)-doped NaTaO3 provides an important guidance for the design and preparation of the visible light photoactive materials.
Synthesis and Formation Mechanism of Hollow Carbon Spheres Containing Fe3N Nanocrystals
Authors: Liu Bo Yang , Jia De Chang , Dong Li Hua , Yin Yan Sheng
Published: September 2009

Hollow carbon spheres containing Fe3N nanocrystals (Fe3N/HCSs) are synthesized by ferrocene and ammonium chloride in high pressure argon at 500 °C. The structure, morphology and properties of the products are characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TG) and vibrating sample magnetometry (VSM). The hollow carbon spheres have diameters of 1-10 µm and shell thickness of hundreds of nanometers. The dimensions of the acicular Fe3N nanocrystals have diameters of ca. 100 nm and lengths of 600-800 nm. The weight percent of Fe3N nanocrystals in Fe3N/HCSs is about 37.8%. The saturation magnetization value of the hollow carbon spheres containing Fe3N nanocrystals is 10.61 emu/g.
Effects of Magnetic Field Gradient on Particle Distributions of Suspension Comprised of both Magnetic and Nonmagnetic Particles Using Two-Dimensional Monte Carlo Simulations
Authors: Peng Xiao Ling , Yan Mi , Ge Hong Liang
Published: September 2009

Functionally graded materials (FGMs) have recently been fabricated under gradient magnetic fields via slip casting, based on the distinct difference in magnetic susceptibility between the components in a suspension comprised of both magnetic particles (MPs) and nonmagnetic particles (NPs). In this work, a physical model of a mixed suspension comprised of both MPs and NPs under a gradient magnetic field is built, base on which the distributions of particles in the suspension under gradient magnetic fields are studied using two-dimensional Monte Carlo simulations, and the effects of magnetic field gradient on the distributions of particles are investigated. The results show that a gradient distribution of MPs is formed along field direction, which is attributed to the translation of MPs. As the magnetic field gradient is increased, the distribution gradient of MPs increases.
Synthesis of Spherical Mesoporous Co-MCM-41
Authors: Sun Peng , Kong Yan , Du Jun , Xu Xin Jie , Wang Jun , Yun Zhi
Published: September 2009

A serious of spherical Co-MCM-41s with different cobalt content was synthesized and characterized by XRD, SEM, N2 isotherms and ICP techniques. The influences of synthesis conditions on the structure were also studied. The use of ascorbic acid as reductant had significant influence on the morphology and the catalytic activity of Co-MCM-41. The prepared samples exhibited higher catalytic activity in the direct hydroxylation of benzene by H2O2 than those with common morphology.
Magnetic Properties of MWNTs-Fe3Al Composite
Authors: Pang Lai Xue , Xing De Jin , Zhang Ai Qin , Xu Jing , Sun Shi Shuang
Published: September 2009

Multi-walled carbon nanotubes (MWNTs)-Fe3Al was prepared by spark plasma sintering. Microstructural investigations show that MWNT remains in the composites. The magnetic properties were investigated with alternating gradient force magnetometer, which shows that the composites still display good soft magnetic property. The MWNTs-Fe3Al composites have a similar magnetic hysteresis loops to that of Fe3Al, indicating the good soft magnetic properties of the composite. Excellent magnetic property implies that MWNT-Fe3Al composites may also have significant potential for applications in electronic-magnetic nanodevice fields.
Preparation and Characterization of Ion Exchange Resin Mixed Polyethersulfone Hybrid Membranes
Authors: Zhang Yu Zhong , Jia Ru , Li Hong
Published: September 2009

Ion exchange resin (IER) mixed polyethersulfone (PES) hybrid membranes were prepared by a phase inversion method, using polyethyleneglycol-400 (PEG-400) and polyvinyl pyrrolidone (PVP) as additives. Two different types of resin, D201 and D061, were incorporated into polyethersulfone dope solution separately with intention of producing highly permeable and hydrophilic membranes. The effect of filler on morphology, pure water permeation, and rejection of bovine serum albumin (BSA) was investigated. It was found that the morphology of hybrid membranes showed a typical asymmetry structure. The amount of IER, the concentration of additives and the temperature of coagulation bath showed to be powerful factors to influence the pore size and pure water flux. Membranes prepared from a solution containing PES concentrations from 13wt% to 15wt%, the pure water flux decreased from 244.6 to 97.5 L/(m2•h). And PVP could serve as an additive to render the hybrid membrane hydrophilic. High values of BSA rejection capacity were performed by the resin mixed polyethersulfone hybrid membranes.
Light Induced Ferroelectric Domain Nucleation in LiNbO3 Crystal
Authors: Chen Yun Lin , Li Hai Wei , Li Yuan An
Published: September 2009

Using the tightly focused visible light (wavelength λ=488nm) illuminating, the ferroelectric domain patterns of the undoped lithium niobate crystal have been demonstrated. The influence of the visible light intensity on the domain nucleation field was investigated. The reduction of nucleation field decreases exponentially with increasing incident irradiation intensity. Once a domain is nucleated it can be dictated by the far-field light diffraction patterns. An assumption is proposed that the reduction of nucleation field is directly related to the defects mobility and structure of the crystals.
Research on Surface Color, Properties of Thermo-Treated Reconstituted Bamboo Lumber after Artificial Weathering Test
Authors: Qin L. , Yu W.J.
Published: September 2009

Reconstituted bamboo Lumber suffers surface and mechanical properties degradation after exposure to outdoor environment. In this paper, Neosinocalamus affinis bamboo bundles was selected to thermo-treated at three temperature levels (160,180 and 200°C) for 2 hours and investigated the effect of xenon-arc light irradiation with water spray on the changes in color, thickness and mechanical properties of reconstituted bamboo lumber. The results indicated that the surface color of the samples changed rapidly during the irradiation process and the change rate decreased as the increasing of thermo-treated temperature. The mechanical properties analysis indicated that MOE wasn’t much affected by the thermo-treated and artificial weathering test, whereas MOR and shear strength decrease after exposure. The thickness swelling after exposure was improved by the thermo-treatment and decreased as the treated temperature increased.
New Magnesium Alloys for Potential Application of Implantation Biomaterial
Authors: Guan Ren Guo , Zhao Tong , Wang Lin Lin , Cui Tong
Published: September 2009

New magnesium alloys with optimized chemical compositions with good biocompatibility were designed. Experimental results show that MZ alloy mainly consists of Ca2Mg5Zn5+α (Mg) and MgZn+MgZn2+Mg2Ca+Zn-Zr compounds. Ca has a strong capability for grain refinement in such alloy. Zr can refine magnesium alloy. Zn addition does not refine the solidification microstructure but plays significant strengthening role during aging treatment. The main strengthening phases of Mg-Zn-Zr alloy are γ(MgZn) and δ(Mg2Zn3). The tensile strength of MZ alloy plate aged at 170°C for 12h is 320MPa, and the elongation-to-failure is 18.4%, the alloy has a potential application of implantation biomaterial.
Influence of Network Structure on Dynamic Mechanical Properties of Cross-Linked Polystyrene / Glass Fiber Composites
Authors: Zhu Quan Yao , Wu Fei , Chen Wen
Published: September 2009

The cross-linked polystyrene prepolymer was synthesized with divinylbenzene (DVB) as crosslinker via free-radical crosslinking copolymerization (FCC) and used as the matrix materials for E-glass fiber reinforced composites. The surface modification was performed by treatment of E-glass fiber with γ-methacryloylpropyl trimethoxysilane (MPS) solution. Fourier transform infrared spectroscopy (FTIR) was used to identify the functional groups on the surface modified glass fibers. Dynamic mechanical thermal analysis (DMTA) of these composites revealed that the dynamic storage modulus (E′) was gradually enhanced with the increasing content of DVB (0~3.0 wt %) whereas the damping parameter (tanδ) peaks are lower and broader, indicating better load bearing capacity. Moreover, the Tg was shifted to higher temperature corresponding to the increasing of crosslinking density. Morphology of fracture surfaces for these composites showed different fiber-matrix interfacial adhesion which was mainly attributed to the variation of crosslinking network structure in the interface.