bluuebunny/crossref_metadata_2025 huggingface dataset:
Modification of Epoxy Resin with Silicone for Electronic Encapsulation Application
Authors: Chen Li Xin , Fan Ling Yu , Gao Li Shuai
Published: June 2014

The reaction was carried out with a solventless (hot-melt) method using epoxy resin (E-20) as a base material and dihydroxydiphenylsilane (DHDPS) or polymethyltriethoxysilane (PTS) as a modifier. IR spectrum, epoxy value of modified epoxy resins indicated that DHDPS and PTS were incorporated into epoxy resin respectively. The influences of silicone contents on softening point and thermal resistance of cured silicone modified epoxy resin systems were studied. The thermal stability was investigated by thermogravimetic analysis (TGA). Effects of the viscosity of packaging slurry on the performance of encapsulated electronic elements were also investigated. In contrast to ED-20 cured system, the thermal resistance, toughness, humidity resistance of ETS-20 cured systems improved more obvious. And ETS-20 has exhibited excellent resistance to the thermal shock cycling test. It indicated that ETS-20 can be applicated for electronic encapsulation. The viscosity of packaging slurry was most appropriate when it was 170~200 mPas.
Effect of Annealing Oxygen Flow Rate on the Properties of Vanadium Oxide Films Deposited by Reactive Magnetron Sputtering
Authors: Zhang Hua Fu , Wu Zhi Ming , Wu Xue Fei , Jiang Ya Dong
Published: June 2014

Vanadium oxide films were prepared on indium-tin oxide glass substrates at low temperature by means of reactive direct current magnetron sputtering and subsequent in-situ annealing process in pure oxygen ambient. In the process of annealing, the oxygen flow rates were varied from 0 to 15 SCCM in order to investigate the effect of annealing oxygen flow rates on the properties of the deposited films. The experimental results indicate that only the vanadium oxide films annealed under relatively high oxygen flow rates (≥ 0.8 SCCM) displayed insulator-metal transition. In addition, it was found that vanadium valence states, surface morphology, optical transmittance and phase transition temperature of the deposited films were sensitive to the annealing oxygen flow rates while the width of thermal hysteresis was relatively insensitive to the annealing oxygen flow rates.
Polymer-Tethered pH-Sensitive Magnetic Nanoparticles for Targeted Delivery of Anti-Cancer Drug
Authors: Shen Yue Qing , Pu Meng Lu , Jiang Wei
Published: June 2014

Efficient delivery of drug to tumor cells is one of the crucial issues in cancer therapy. This letter addresses for the first time that poly (acrylic acid) (PAA), a pH-sensitive polymer, is tethered to the surface of the nanoparticles by chemical grafting. The release rates of doxorubicin (DOX) are subsequently studied in vitro. The results reveal that DOX can be released preferentially at the desired lysosomal pH, and show that the anti-cancer drug carrier can be applied to the biomedical applications.
Structure and Mechanical Properties of Starch/Styrene-Butadiene Latex Composites
Authors: Chen Gang , Zhu Zheng Jun , Salminen Pekka , Toivakka Martti
Published: June 2014

The structure of the starch/styrene-butadiene latex composites was characterized using Scanning Electron Microscopy (SEM). In order to get a better contrast between starch and latex, OsO4 were used to stain latex. Ion-beam cutting and liquid nitrogen cracking were employed to fabricate qualified cross-sections for SEM characterization. During drying, starch and latex migrate, creating non-uniform structure with latex dominated in the lower surface (next to the substrate) and starch in the upper surface (open to the air). The film formation of latex is slower than the starch/latex film forming. Phase separation occurs with starch granules embedded in the latex-starch matrix, reinforcing the composites. The analysis of composite structure and use of Perera approach indicate that good adhesion is present between latex phase and starch phase, starch granules and latex-starch matrix. When the latex is substituted by starch, the elastic modulus and tensile strength increase whilst the elongation at break decreases. When the volume fraction of starch is higher than 41.7 %, increasing starch content, the increase of ultimate tensile strength and elastic modulus accelerate, whereas the elongation at break decreases slower, which may arise from the phase co-continuity of starch.
The Release Characteristics of Different Model Drugs from Medicated PLGA Microspheres
Authors: Chen Tong , Liang Yuan Yuan , Zhao Ying Ge , Zhang Xiao Yun , Qi Tong Sheng , Shang Qing
Published: June 2014

In this study, four model drugs, i.e., Meloxicam (MEL), Risperidone (RIS), Eprinomectin (EPR), and Bull Serum Albumin (BSA), were encapsulated in PLGA microspheres via solvent evaporation methods. The encapsulation efficiency and in vitro release profiles of different drugs with various water solubilities from medicated PLGA microspheres were investigated. The surface morphologies of microspheres were detected by scanning electron microscope (SEM). The release characteristics of the model drugs from the medicated microspheres were carried out in the phosphate buffer solution (PBS), pH7.4, at 37 °C. Studies found that the water solubility of model drugs had significant influences on their in vitro release profiles and the release rates of four model drugs were in the orders of BSA＞MEL＞RIS＞EPR.
Preparation, Characterization of Cellulose Fibers Grafting by β-Cyclodextrin and their Application for Antibacterial Products
Authors: Dong Chao , Ye Ying , Qian Li Ying , He Bei Hai , Xiao Hui Ning
Published: June 2014

Cyclodextrins (CDs) can form inclusion complexes with a variety of molecules making them very attractive in different areas, such as pharmaceutics, biochemistry, food chemistry and papermaking. In this communication the preparation of β-cyclodextrin-grafted cellulose fibers was carried out by reacting β-cyclodextrin with cellulose fiber via citric acid (CA). Both fourier transform infrared (FTIR) and cross polarization magic angle spinning solid state nuclear magnetic resonance (CP-MAS NMR) indicated that β-CDs had been chemically attached to cellulose backbone through the formation of ester bonds. Furthermore, the β-CD-grafted cellulose fibers formed inclusion complexes with ciprofloxacin hydrochloride (CipHCl). And the β-CD-grafted cellulose fibers loaded with CipHCl showed excellent antibacterial activity against E.coli and S.aureus.
Prediction of the Tertiary Structure and the Dimerization Interface of FNR Protein in Klebsiella pneumoniae
Authors: Zhang Qing Rui , Li Xia
Published: June 2014

FNR (fumarate nitrate reduction regulator) is an important oxygen regulation protein, which plays a major role in altering gene expression between aerobic and anaerobic conditions. In this study, the tertiary structure of FNR protein in Klebsiella pneumoniae was established using homology modelling. The model was modified and optimized using molecular mechanics and molecular dynamics simulations. In addition, Support Vector Machines (SVMs) was applied to predict the possible binding sites patches of FNR. The residues conservations were further analyzed and it was found that the Asn138-Ser162 region of FNR protein was the putative dimerization interface.
Highly Efficient Adsorption of Eriochrome Black T in Wastewater on Mesoporous Alumina Sphere
Authors: Liu Heng , Tian Na , Tian Ya Yang , Dai Chu , Wang Yan Xin
Published: June 2014

The present study presents the adsorption behavior of mesoporous alumina sphere for Eriochrome black T (EBT) azo dyes. The batch adsorption experiments were carried out to optimize various experimental parameters such as contact time and dye concentration. The maximum adsorption of EBT was achieved 312.5mg/g. The kinetic studies revealed that the adsorption process followed the pseudo-second-order kinetic model. The adsorption behavior was analyzed by Langmuir and Freundlich isotherms. The values of correlation coefficients (R) showed that the Langmuir isotherm model found to be best fit. Results of study showed that Mesoporous alumina sphere proved to be highly effective for the removal of selected azo dyes.
Adsorption Characteristics of Methacrylic Acid-Styrene Copolymer onto Azoxystrobin Particles Surfaces
Authors: Hao Han , Feng Jian Guo , Chen Wei Tao , Liu Wen Jun , Wu Xue Min
Published: June 2014

In order to investigate the feasibility of using methacrylic acid (MAA)-styrene (St) copolymer as dispersants to disperse azoxystrobin particles in aqueous suspension, the adsorption kinetics, isotherm and thermodynamics of MAA-St copolymer onto azoxystrobin particle surfaces were studied by batch equilibrium experiments. The results showed that the adsorption process followed the pseudo-second-order kinetic model with the entire adsorption, adsorption rate decreased with the initial concentration of MAA-St copolymer increasing. The equilibrium data were fitted with Langmuir isotherm equation better. The thermodynamic parameters were calculated, which indicated that the adsorption was a spontaneous and exothermic process in nature, and higher temperature is not beneficial to that adsorption process.
Simultaneous Reduction and Immobilization of Cr2O72- in Metakaolinite-Based Geopolymer Complexed Reductant
Authors: Chen Jie Yu , Lei Xin Rong , Tao Sun
Published: June 2014

Reduction and immobilization of Cr (VI) as Cr2O72- is investigated by using metakaolinite-based geopolymer complexed reductant. Without reductants, the leached Cr concentration from metakaolinite-based geopolymer containing Cr (VI) is very high. Adding reductants as FeCl2·4H2O, FeSO4·7H2O, and Na2S·9H2O respectively during geopolymerization, the leached Cr concentration is below 5 mg L-1 with high Cr immobilization rate above 99 %. By comparison with the immobilization of Cr (III), the added reductants reduced Cr (VI) to Cr (III) which can be locked successfully in the amorphous structure of geopolymer. Meanwhile, Cr (VI) initial concentration is lower than 0.7 wt. % in metakaolinite-based geopolymer, the above reductants can all meet the requirements. While for Cr (VI) initial concentration larger than 0.7 wt. %, Na2S·9H2O is more appropriate. Such a simultaneous reduction and immoboilization process enables the feasibility of using metakaolinite-based geopolymer complexed reductant to implement a one-step procedure for chromite ore processing residue cleanup.
Recycled Paper Cellulose Aerogel Synthesis and Water Absorption Properties
Authors: Feng Jing Duo , Nguyen Son T. , Duong Hai M.
Published: June 2014

By applying sodium hydroxide/urea and a sample freeze drying method, we successfully synthesized green cellulose aerogel from paper waste for the first time. We adjusted the cellulose concentration from 1.5 percents to 4 percents in the initial hydrogel. They yielded densities changing from 0.03-0.1 g/cm3.The absorption capacities varied from 9 to 20 times of their own weight. To investigate the water absorption capacity in relationship with the initial chemical dosage, we changed the input amount of urea and sodium hydroxide, which is the first study ever. The thermal conductivity of the 2 percents sample ranged from 0.029-0.032 W/mK. Besides, the material has a high potential to be used in diaper industry as it is biodegradable which is better than most super absorbent polymers.
The Synthesis and Electro-Optical Properties of Perylene Dicarboximide Dimer with Electron Withdrawing Groups
Authors: Wei Hui Min , Zhao Nan , Jiang Nan , Duan Wen Feng , Gao Bao Xiang
Published: June 2014

Perylene dicarboximide dimer with electron withdrawing groups were synthesized and fully characterized by 1H-NMR and 13C-NMR spectra. The effects of the substituted groups on the optical and electrochemical properties of the two compounds were investigated. The ∏-∏* absorption peak of the perylene dicarboximide dimer compounds were red shifted from 525nm to 535nm. The band gaps of the dimer could be tuned from 2.28 eV to 2.13 eV. The first reduction wave of the dimer with electron withdrawing groups is shifted by 60 mV to more positive potential compared to that of perylene dicarboximide, suggesting the enhanced electron affinity. Furthemore, the dimer exhibited intermolecular aggregation, and decrease fluorescence quantum yield.
Preparation and Properties of Electroactive PANI by Electrodeposition
Authors: Li Bao Song , Yu Yang , Zhang Wei Wei , Zhang Lei
Published: June 2014

Electroactive polyaniline fibres have been prepared by eletrodeposition in aniline and hydrochloric acid aqueous media. The influence of applied potential and polymerization time on the electrochemical polymerization of polyaniline fibres have been investigated. Morphology and structure of PANI were characterized by scanning electron microscopy. Electrochemical behaviors of PANI were studied by cyclic voltammetry. The results show that the applied potential and the polymerization time have a crucial influence on the polymerization rate and conductivity of the PANI prepared. It indicates that the properties, as well as the morphology of PANI, could be changed by applied potential and po-lymerization time, etc. This change might result in the quality of PANI suitable for specific applications.
Electrocatalytic Hydrogenation of Oxalic Acid to Glyoxylic Acid on a Self-Organized TiO2 Nanotube Electrode
Authors: Qian Yang , Zhao Feng Ming , Qiu Qing Qing , Ma Chun An
Published: June 2014

A study for electrocatalytic hydrogenation of oxalic acid has been reported using the self-organized TiO2 nanotube electrode prepared by anodic oxidation method. The prepared electrode was characterized by SEM and XPS. The electrocatalytic activity of the TiO2 nanotube electrode was evaluated by CV and galvanostatic electrolysis. The CV studies and electrochemical experiments showed that TiO2 nanotube electrode exhibited high electrocatalytic activity. In addition, the surface of TiO2 nanotube electrode developed into a periodic lattice of nanopores after electrolysis, which makes it find a potential application as electrocatalysts.
Low Temperature Preparation of Mullite Whisker via Non-Hydrolytic Sol-Gel Process Combined with Molten Salt Method
Authors: Fu Kai Lin , Jiang Wei Hui , Feng Guo , Liu Jian Min , Wu Qian , Miao Li Feng , Chen Ting , Zhang Quan , Wang Hong Da , Zha Jian Rui
Published: June 2014

Mullite whisker was prepared at low temperature via non-hydrolytic sol-gel (NHSG) process combined with molten salt method. The influence of heat treatment temperature was studied on the morphology and the microstructure of whisker, and its growth mechanism was also described. The results show that the mullite whisker appears at the lowest temperature of 750 °C, and optimized mullite whisker can be prepared at 850 °C with the growth direction of [00, whose diameter is in the range of 170~300 nm with the aspect ratio of >30.
Co-Ni Bimetallic Catalysts Coated on Cordierite Monoliths for Hydrazine Decomposition
Authors: Pakdehi Shahram Ghanbari , Salimi Mozaffar , Rasoolzadeh Maryam
Published: June 2014

The preparation conditions to obtain cobalt-nickel monolithic catalyst with high loading and homogeneous distribution are studied. Washcoating of raw monolith with gamma alumina solution was examined and characterized by SEM. A uniform layer of alumina washcoat as a support for active phase was achieved in this process. Also the effect of the molarity of solution and the number of impregnation were studied to obtain different loading of active phase on monolith walls. Catalysts with 38.81, 20.44 and 3.22 wt.% of loading were obtained by four steps of impregnation in active phase solution with 3.33, 1.42, 0.3 of molarity, respectively. It was found that increase in concentration of active phase loading leads to increase in active phase loading but reduces the uniformity of active phase distribution.
Optimization Design on Variable Cycle Engine Performance Based on Genetic Algorithm
Authors: Zhang Yi , Yu Zhu Ma , Zheng Xiao Dong , Du Xuan
Published: June 2014

The article have described the optimization of the engine performance problem as nonlinear multi-objective programming, and have analyzed the operation principle of the variable cycle engine, made models of maximum thrust , maximum unit thrust, minimum oil consumption, and then adopts the genetic algorithm to solve the model, gained the guide vane angle of CDFS,the guide vane angle of low-pressure.Turbine and the nozzle throat area when the performance is optimal . It is a problem about multi-objective optimization, obtained a series of satisfactory solution and then selected a set of approximate optimal solution as the final argument. Lastly, The matlab software is used to illustrate the effectiveness of the results.
Cylindrical Cam Profile by CMM Based on Pro/E Model
Authors: Ma Chao , Wang Bin , Xu Liu , Yu Yan , Li Ruo Lei
Published: June 2014

The development of CAD and CAM technology makes it more process to inspect surfaces of the part, this is usually carried out by CMM. With the research of the error analysis of cutter location for unequal diameter side milling of cylindrical cam, the technology using CMM to inspect surfaces by Pro/E CAD model is analysed from some key aspects: Pro/E modeling; set up coordinate ; and probe compensation.
Research Status and Development Trend of Dimethyl Ether Fuel Supply System
Authors: Sun Jing , Zhang Guang De , You Cai Xia , Yao Qiang , Hou Zhong Hai
Published: June 2014

A survey of study on dimethyl ether engine fuel supply system at home and abroad was described, including pump-pipe-nozzle system and common-rail fuel supply system. The main trouble of practical application of dimethyl ether engine is wear and leakage problems in the fuel delivery system caused by low viscosity of dimethyl ether. For controllable premixed combustion of dimethyl ether engine, a fuel injection system is developed which is consisted of a diaphragm pump and a wear self-compensation nozzle or an independent lubrication nozzle. The system is expected to solve the above problems essentially and becomes a development direction for the future.
The Hardware Design of Test-Bench for Motor Energy Efficiency Based on Torque-Meter Method
Authors: Zhou Hou Qiang , Zhang Yan Jun , Liu Xiu Fen , Zhang Zi Hui , Rao Wei , Zhang Ming Shan
Published: June 2014

According to the demand of accuracy detection of the motor energy efficiency, the hardware of testing bench for motor based on torque-meter method was designed. A design emphasis on loading equipment and torque sensor was introduced in accordance with the requirements of torque meter method, realized the rapid response of the load, the low speed stability of the work and electrical energy reutilization. The proposed error modification method ensured the accuracy and reliability of test results.
Parametric Design of Jib in Rapid Design System of Tower Crane
Authors: Wang Liang Wen , Mu Xiao Qi , Wang Xin Jie , Du Wen Liao
Published: June 2014

In rapid designing system of tower crane, the parametric design of jib is one of the key points in the process. The whole process of parametric design for the jib is introduced in this paper, which includes parameterization of a single part, parameterization of entire jib, jib design with the characteristic of changing arms for tower crane and design method of automatic assembly for the jib, etc. Realization of the jib parametric design lays foundation for the rapid design system of tower crane.
Research on Crack of Cylinder Bracket Based on Numerical Simulation and Finite Element Analysis
Authors: Luo Hong Fei , Wang Jian Cheng , Lei Jie , Cui Qing Bin
Published: June 2014

During type test experiment of loading mechanism, there exist a problem of deformation and cracking, in order to solve this problem, movement of cylinder under the action of gas source is analyzed by numerical simulation, based on this, use finite element analysis to execute dynamics simulation analysis, the effect of high-speed collisions when loading mechanism work it bring to cylinder bracket is analyzed, and the reason of cylinder bracket crack is find out. The modify method is put forward, it is proved by experiment that, after modify, the working reliability is significantly improved.
Design and Optimization of Lifting Mechanism Based on a Kind of Rotary-Type Desk
Authors: Wang Jun Fang , Hu Lan Xiong , Wang Chao Chao
Published: June 2014

This article is aimed at a kind of rotary type desk that can move, so we designed a scissor–type lifting mechanism and use MATLAB to optimize it’s rod length so as to prove the rationality of mechanism design.
The Simulation and Improvement of the Heating Furnace Lifting Framework Based on ANSYS
Authors: Shi Jia Lian , Meng Gui Yun , Zhu Chang Qi , Wang Dong
Published: June 2014

Step-type heating furnace is a kind of mechanized furnace hearth furnaces, due to the corrosion of heating furnace lifting framework is serious, which needs to repair. This article uses the Pro/E to build heating furnace lifting framework model, and then it is leaded to ANSYS which can analysis the stress of framework. Firstly, the framework model that has been corroded and damaged should be analyzed for summing up the framework’s damage and dangerous points and determining the framework reparative plan. Then framework model after being repaired needs to analyze with the same load, the analytical result of which should be compared with that of original design’s framework, and reparative plan should be corrected and examined. Finally, the reasonable framework reparative plan will be determined.
The Safe Auxiliary System for Aircraft’s Forced Landing
Authors: Wang Xiao Jin , Li Xin , Peng Xiao Ling , Fang Qi Feng
Published: June 2014

Aiming at the abnormal landing of the aircraft which caused by the invalidation of the undercarriage, a safe auxiliary system for aircraft’s forced landing is proposed. Firstly, the article introduces the basic compositions and the main functions of each part in the system, and proposes the undercarriage robot based on the aircraft arresting system and also the underground rail system based on the steam-driven catapult principle is put forward. Secondly, the detail introductions on the system’s operating principles for aiding the forced landing of aircraft are given separately from starting, docking, decelerating and separation. At last, an expert control system based on knowledge base is proposed for realizing the calculation of docking position, velocity matching and the optimal decelerating scheme.
Analysis on Electromagnetic Properties of Lapped Joints
Authors: Xia Wen Tao , Li Hui , Zhang Shi Quan
Published: June 2014

There is little work on electromagnetic properties of lapped joints at the metal surface. In this paper, we improve the application of Finite-Difference Time-Domain (FDTD) to the total field border and the absorption conditions in the computed areas for electromagnetic coupling of lapped joints. The process of electromagnetic pulse penetrating into the coupling of lapped joints is simulated. Equivalent magnetic flows at the aperture of the joints are computed. Our work provides an algorithm that can be used to investigate the pattern of coupled resonance of lapped joints.
Study and Design of CAN/LIN Hybrid Network of Automotive Body
Authors: Huang Peng
Published: June 2014

Due to the extensive application of automobile electronic control technologies, the demand of automotive network is growing. Automotive operation data sharing has become a feature of the automotive network. CAN network is most widely applied in the automobiles. LIN network is a supplement for CAN network in practical application. The hybrid network of CAN/LIN can improve the stability of the system, and also reduce network cost without influencing the performance of the network. In this paper, through the study of CAN/LIN hybrid network technologies of automotive body, a system scheme of the automotive body network with CAN/LIN dedicated gateway is proposed.Keyword: CAN Bus; LIN Bus; Bus network technology; CAN/LIN hybrid network
The same Space-Time Exact Matching Method for the RFID and Image of Moving Vehicle under High Speed Free Flow Road Conditions
Authors: Wang Zhan Bin , Wang Jing Cheng , Tan Guang Yun
Published: June 2014

Along with the RFID applied on vehicle technology researching, it is very important that the RFID technology and video technology were combined to management the vehicle moving on the road. Under several projects supported by government, we have a good opportunity to experiment and solve the exact matching problem of the RFID and image of moving vehicle. Firstly, the same space-time exact matching method for the RFID and image of moving vehicle under high speed free flow road conditions was proposed. Secondly, the experimental scheme was made by introducing the vehicle sensing coil to bridge the RFID and image information. Lastly, we obtained a large number of experimental data and made a lot of comparison analysis. The experimental results shown that the method is scientific and practical.
A Fast Trajectory Planning Algorithm Research for Point-to-Point Motion
Authors: Li Chun Jun , Liu Chang Liang , Wang Gu Chang , Liu Lin , Sun Ye
Published: June 2014

This paper studied the third-order S-curve trajectory planning for point-to-point motion. By comparing with the pure third-order S speed curve, here further discussed the value of , and , then obtained four types of trajectories of the general third-order S-curve, and put forward the fast third-order S-curve trajectory planning algorithm.
Modifying Sodium Bicarbonate for Foaming Polymers
Authors: Yao Si Jia , Zhou Zhou Fa , Ye Feng , Tian Zhe , Wang Shu Mei
Published: June 2014

Sodium bicarbonate was modified with citric acid by solution coating method, and used to increase the foaming temperature and narrow the range of decomposition temperature. The thermodynamic parameters of sodium bicarbonate and modified sodium bicarbonate were studied by DSC and TG. After the modification, the initial decomposition temperature of sodium bicarbonate raised from 112.6oC to 146.9oC, endothermic peak temperature from 150.5oC to 165.9oC, the range of decomposition temperature narrows from 56.2oC to 31.5oC. After modification, sodium bicarbonate shows faster rate of decomposition.
Study of Breeze Vibration of Overhead Transmission Lines with Dampers Using FEM Analysis
Authors: Yang Jian Wei , Chen Ping , Zhang Yu , Yu Zhu Ma , Liu Xin Long
Published: June 2014

The vertical, steady-state breeze vibration of transmission line with dampers attached are studied using FEM analysis. The lines are simulated by cable element, the dampers by mass element and beam element. The parameters of FEM emulation mode such as breeze vibration force, the conductor self-damping and dampers damping are emphasized by the energy equivalent theory. The breeze vibration force induced by vortex is educed by wind power curve, the hysteresis damping and friction damping of conductor and damper are translated into viscous damping. Results of the FEM emulation show the calculation accuracy of natural frequency of dampers, and prove that it can effectively restrain breeze vibration of transmission lines by installing dampers. The method lays foundation for further research on protecting breeze vibration of transmission lines.
Study on Inspection Methods for High-Speed Progressive-Die Punched Strips
Authors: Hai Zheng Ping , Yang Zhi Hong , Ning Jian Hua
Published: June 2014

The inspection of sheet strips post high-speed punching mainly relies on the manual off-line inspection with basic inspection equipment or CCD equipment. Such inspections cannot reflect the real-time conformity of strip machining, and in severe cases, lead to rejects in batches, causing a tremendous waste in production. Now that the application of charge-coupled device (CCD) technology in product inspection is relatively mature, it would be a very good thought to adopt the CCD technology to realize real-time online inspection of conformity of the high-speed punched strips. KeyWords: CCD technology; strip; online automatic inspection; progressive die
Fatigue Life Analysis of Mine Hoist Drum
Authors: Peng Xia , Gong Xian Sheng
Published: June 2014

This article is based on a certain type of hoist drum, Moreover, we make the stress and mode analysis for the drum, and make preliminary check on it. Then find the position of the weak section, we calculate the force in each stage of hoisting system and draw force-timing load spectrum,we translate it into stress function of weak link. Based on above studies and conclusion, in line with the materials of the drum and Fatigue characteristic parameters and appropriate fatigue lifetime prediction model, we analysis the fatigue performance, in the end get the distribution of the drum’s fatigue life and the life of plane of weakness.
Study on Dynamics Simulation of Long Range Rocket Artillery Launch Guider in Firing Process Based on ADAMS
Authors: Cui Qing Bin , Wang Jian Cheng , Huo Xin Min , Luo Hong Fei
Published: June 2014

In this paper, three-dimensional models of the long range rocket artillery launch guider is created by Pro/E software, and the virtual prototype of the long range rocket artillery launch guider is built based on ADAMS software. Finally, the author analyzes the virtual prototype with dynamics simulation, taking the launch guider's firing for exampel. It ends with the variance of characteristics of launch guider under different angular circumstance based on the analysis of simulation results and corresponding charts. The result proves the correctness and feasibility of the virtual prototype of the long range rocket artillery launch guider. It has the great significance to the lifetime prediction, structural design, fault diagnosis of the long range rocket artillery.
Joining Processes by Plastic Deformation
Authors: Mori Kenichiro
Published: June 2014

As the scale and complexity of products such as aircraft and cars increase, demand for new functional processes to join mechanical parts grows. The use of plastic deformation for joining parts potentially offers improved accuracy, reliability and environmental safety as well as creating opportunities to design new products through joining dissimilar materials. This paper aims to provide an overview of the state of the art in such joining processes, including cold welding, friction stir welding, joining by forming, self-pierce riveting and mechanical clinching. The paper includes description of the mechanism of joint formation, joint strength and applicability.
Microorganisms as a Replacement for Metal Working Fluids
Authors: Redetzky Marvin , Rabenstein Andreas , Palmowski B. , Brinksmeier Ekkard
Published: June 2014

Most of the several billion liters of metalworking fluid (MWF) used worldwide and annually are water-based and thus prone to a microbial contamination. The microbial growth leads to a deterioration and therefore to a loss of quality and technical performance. In most cases, biocides, which pose a potential risk to health and environment, are used to reduce the microbial load. To avoid these limitations, the paradigm shift of using microorganisms in a positive way in a manufacturing process as a lubricant is investigated in this paper. Some microorganisms are able to synthesize equivalent MWF components like e.g. fatty acids or sulfur compounds. Due to this fact, it is possible to create a regenerative system on a microbiological basis for the substitution of mineral oil containing MWF components. To demonstrate the lubrication potential of bacteria, preliminary investigations were conducted on a Brugger-tribotester. Against this background, the approach presented here intends to investigate the lubrication properties of special microorganisms and the influence of the microbial cell counts on the lubrication behavior respectively. The results of the tribological tests show that the microbial-suspensions exhibit Brugger-values as high as highly concentrated conventional MWF and indicate the potential to replace these respective components.
Magnetic Pulse Welding by Electromagnetic Compression: Determination of the Impact Velocity
Authors: Lueg-Althoff Joern , Lorenz Amanda , Gies Soeren , Weddeling Christian , Goebel Gunther , Tekkaya A. Erman , Beyer Eckhard
Published: June 2014

The implementation of multi-material concepts and the manufacturing of modern lightweight structures, for example in automotive engineering, require appropriate joining technologies. The ability to join dissimilar materials without additional mechanical elements, chemical binders, or adverse influences of heat on the joining partners is key in reaching the desired weight reduction in engineering structures. The Magnetic Pulse Welding (MPW) process meets these demands, making it a viable alternative to conventional thermal welding and mechanical joining processes. The present paper focuses on the analytical determination of the impact velocity as one of the key parameters of MPW processes. On the basis of experimentally recorded data concerning the course of the discharge current and geometrical parameters of the welding setup, the respective velocity is determined. A comparison with measurement data gained by Photon Doppler Velocimetry is performed.
A Novel Method to Investigate the Principles of Impact Welding: Development and Enhancement of a Test Rig, Experimental and Numerical Results
Authors: Pabst Christian , Sharafiev Semen , Groche Peter , Wagner Martin F.X.
Published: June 2014

The two common processes of impact welding, explosion welding and electromagnetic pulse welding, may offer great technological advantages, but at the same time exhibit poor observability due to the use of explosives and a highly transient behavior, respectively. A novel test rig is developed and enhanced to collide and weld specimens purely mechanically. Besides its simple build-up and the easy and safe operation, the test rig allows setting crucial process parameters almost independently. The test rig’s construction and improvement is described. A trigger method for high speed imaging is developed and tested. The numerical simulation of the impact shows that the conditions directly at the welding zone are predictable and can be adjusted accurately. Finally, the preparation of specimens to evaluate the influence of surface roughness and grain structure is discussed.
Realization of Al/Mg-Hybrid-Joints by Ultrasound Supported Friction Stir Welding - Mechanical Properties, Microstructure and Corrosion Behavior
Authors: Strass Benjamin , Wagner Guntram , Conrad Christian , Wolter Bernd , Benfer Sigrid , Fürbeth Wolfram
Published: June 2014

Fusion welding of dissimilar metals is in the most cases difficult or even impossible as a result of different melting points and the development of undesirable brittle intermetallic phases. This often leads to joint strengths considerable below the tensile strength of the base materials. By using Friction Stir Welding (FSW) it is possible to reduce the development of the intermetallic phases of Al/Mg-joints significantly but not to avoid them completely. Hence a hybrid welding system at the WKK of the University of Kaiserslautern was developed called “Ultrasound Supported Friction Stir Welding (US-FSW)” with the aim to shatter the brittle interlayer lines and to scatter fragments in the welding area during the FSW process. Pre-investigations have shown that for Al/Mg-US-FSW-joints the strength can be increased up to 30% in comparison to conventional FSW. Moreover for the reliable detection of nonconformities in the weld during a post-process inspection by suitable non-destructive testing (NDT) methods is necessary. Also there is a strong need for better process monitoring and control by in-process NDT methods. Furthermore the corrosion behavior of the basic materials and hybrid-joints was investigated by electrochemical methods indicating an increased corrosion of the Mg alloy in the area of the Al/Mg-butt weld.
Friction Press Joining of Laser-Texturized Aluminum with Fiber Reinforced Thermoplastics
Authors: Wirth Franz Xaver , Fuchs Alexander N. , Rinck Philipp , Zaeh Michael Friedrich
Published: June 2014

Friction Press Joining (FPJ) is a suitable method for producing composites of aluminum and thermoplastics in lap joint configuration, which is based on modified Friction Stir Welding (FSW). During the joining process, a rotating cylindrical tool is pressed onto an aluminum surface. The resulting friction generates heat that is conducted to the bonding zone, leading to localized softening of the thermoplastics. In combination with the tool’s axial force and a suitable pre-treatment of the aluminum surface, a resilient composite compound is created. This paper presents the results of a surface pre-treatment of aluminum using laserradiation. The textures are essential for a strong connection, as they can significantly influence effective joining mechanisms, such as microscopic and macroscopic form fit. The experiments were carried out using different surface treatments by means of a single-mode laser for joints of aluminum (EN AW-6082 T6) and glass fiber reinforced polyamide (PA6 GF15). The aim of the study was an increased understanding of process behavior and joining mechanisms. The shear strength could be increased by 40 % compared to previous studies with the presented laser surface treatment.
High Speed Joining by Laser Shock Forming
Authors: Veenaas Stefan , Vollertsen Frank
Published: June 2014

Due to an ongoing trend of function compaction miniaturization gets more and more important in industrial production. This makes hybrid joints under various conditions also in the micro range necessary. Existing joining solutions often have restrictions due to the principle of joining. Thus in this article a new high speed forming method for the micro range is shown, which is based on plastic deformation by laser induced shockwaves. First of all it is shown how metal sheet-sheet joints can be realized with this method. With the produced joints tensile tests are carried out, where a maximum shearing force of 26.7 N could be achieved. For a detailed process understanding, the near-field of the acting pressure of the TEA-CO2-laser induced shockwaves is measured. Moreover it is determined that the ignition point of the TEA-CO2-laser induced plasma out of aluminum is about 8 mm above the surface.
Determination of Friction Coefficients of Interstice of a Shaft-Hub-Connection Manufactured by Lateral Extrusion
Authors: Dörr Florian , Funk Michael , Liewald Mathias , Binz Hansgeorg , Savino Marco
Published: June 2014

A combination of several manufacturing process steps in a simultaneous manner allows savings in energy costs, reduced investment and economizing logistical efforts. In particular, this investigation deals with manufacturing and joining of a frictionally engaged shaft-hub-connection by lateral extrusion. One key challenge of such new process management is the prior layout of both optimal friction conditions during manufacturing process on the one hand and highly expected static friction interaction of joined components in order to transmit tangential and axial forces on the other hand. Therefore, cylindrical, thin-walled hubs have been manufactured and joined to shafts. Several parameters describing the tribological system between shaft and hub such as contact surface topographies and lubricant, have been varied within this study. By measuring the radial deformation of the hub, the contact pressure is determined and a normal force applied to the contact surface of shaft and hub is calculated. When separating hub and shaft in a destructive manner, an extensive axial tensile force is applied and measured. According to Coulomb's friction law, specific friction coefficients are calculated depending on manufacturing process parameters as mentioned above.
Effect of Substrate Temperature on the Properties of Hafnium Nitride Films Prepared by DC Sputtering
Authors: García-González Leandro , Hernandez Torres Julian , Peredo Luis Zamora , Serrano Andrés Alfonso Rodríguez , Vázquez Cecilia Stephanie Loyo , Arias Ayesha Margarita Courrech , Ramírez Nelly Flores
Published: June 2014

Hafnium Nitride (HfN) thin films were fabricated by sputtering technique reaching a thickness of 250 nm. The substrate temperature was varied in 25, 100, 200, 300, 400 and 500 °C. Hardness, coefficient of friction, electrical resistivity and corrosion behavior of HfN thin films were studied. The structural changes were analyzed by X ray diffraction (XRD). The film growth at room temperature showed the highest hardness value (15.8 GPa), higher electrical resistivity (1.23´1013 mW-cm) and the lowest coefficient of friction (0.37), as well as the best polarization resistance. Increased substrate temperature tends to decrease the corrosion resistance (icorr: 17.50 nA/cm2 to 254.9 nA/cm2) and friction coefficient (0.37 to 0.58), however, all values are above of corrosion resistance and friction coefficient reported by TiSiNO and TiSiN films. Images of scanning electron microscopy (SEM) show that films presented low surface damage with no evidence of corrosion products.
Electrical Characterization of Interface Defects in MOS Structures Containing Silicon Nanoclusters
Authors: Arias Abraham , Nedev Nicola , Curiel Mario , Nesheva Diana , Manolov Emil , Valdez Benjamin , Mateos David , Contreras Oscar , Raymond Oscar , Siqueiros Jesus M.
Published: June 2014

The effect of annealing temperature on the properties of c-Si wafer/SiOx interface (x = 1.15 and 1.3) is studied by Transmission Electron Microscopy and Capacitance/Conductance-Voltage measurements. Furnace annealing for 60 min at 700 and 1000 °C is used to grow amorphous or crystalline Si nanoparticles. The high temperature process leads to an epitaxial overgrowth of the Si wafer and an increase of the interface roughness, 3-4 monolayers at 700 °C and 4-5 monolayers at 1000 °C. The increased surface roughness is in correlation with the higher density of electrically active interface states.
Microstructural and Thermal Characterization of Copper Based Composites for Thermal Management in Electronic Packaging
Authors: León Carlos Alberto , Rodríguez-Ortiz Gabriel , Aguilar-Reyes E.A. , Nanko Makoto , Takeda M.
Published: June 2014

Copper based composites with 30, 40, 50 and 60 vol.% Al2O3 were fabricated by powder metallurgy and consolidated by pulsed electric current sintering (PECS). For the purpose of determining the advantage of using coated fillers, composite alumina particles with 18 vol.% copper were prepared by electroless copper plating. Coatings were continuous and homogeneous through alumina surface. Thus, composites consolidated by the modified process increased contact between the matrix and filler, which resulted in superior thermo-physical properties. Thermal conductivities of 210-99 and 227-114 W/mK were obtained for Cu/Al2O3 made by the admixture and the coated filler method, respectively. Such superiority is mainly attributed to the continuity in the matrix phase; the thermal conductivity values observed are similar to those shown by the traditional materials used in electronic packaging. The coefficient of thermal expansion was slight lower in composites fabricated by the coated filler method; values in the ranges of 14-11 and 13-10.5 μm/m°C were obtained for the admixture and the coated filler method, respectively.
In Vivo Biocompatibility of Dental Scaffolds for Tissue Regeneration
Authors: Villarreal-Gómez Luis Jesús , Vera-Graziano Ricardo , Vega-Rios Maria Raquel , Pineda-Camacho Jose Luis , Mier-Maldonado Paris Astrid , Almanza-Reyes Horacio , Cornejo Bravo Jose Manuel
Published: June 2014

It is important to develop scaffolds that resemble the extracellular matrix, thereby facilitating tissue regeneration. The objective of this work is to evaluate the biocompatibility of scaffolds of poly (L-lactide) with pure and grafted hydroxyapatite, at various concentrations of reinforcement, in Wistar Rat tissues, to evaluate the potential application on hard tissue regeneration. The biocompatibility tests were carried out in vivo in Wistar rats by implanting the material into the subcutaneous tissue and muscle from 1 to 14 weeks and evaluating the surrounding tissue stained with hematoxylin-eosin. All variants of scaffolds provoked an inflammatory response from mild to moderate, without showing necrosis. These results show that even if there is recognition of the implanted materials by the immune system, it does not provoke a violent response that damages the surrounding tissue, implying that the materials to be implanted for use in hard tissue can cause a mild reaction and tolerable long term effect that does not prevent their later use in hard tissue regeneration.
Photocatalytic Degradation of Malachite Green Dye and Pharmaceuticals Using Co:TiO2 Thin Films
Authors: Perez-Alvarez Jonatan , Solis Casados Dora Alicia , Romero Saul , Escobar-Alarcón Luis
Published: June 2014

The crossed beam pulsed laser deposition technique was successfully used to prepare Co:TiO2 thin films with different cobalt concentrations and a band gap as low as 2.0 eV. The aim of this work is to report the application of TiO2 thin films modified with different amounts of cobalt (Co:TiO2) as catalysts in the degradation of a malachite green (MG) solution as well as in solutions containing pharmaceutical wastes such as the analgesics diclofenac and naproxen. For catalyst activation an UV lamp with emission at 254 and 404 nm was used as the energy source. It was followed the decrease in the characteristic absorption band of the different polluted solutions over the reaction time. In general terms, the obtained results showed that samples containing cobalt exhibited better photocatalytic performance than the undoped TiO2 films. An optimal cobalt content in the film was found that provided the highest degradation for the different solutions.
Strength Insertion Implant Fixed on Trabecular Bone Density Based on Insertion Torque and Pull Out
Authors: López Clara Isabel G. , Moreno Juan Carlos M. , Pinillos Julio C.
Published: June 2014

The main purpose of this research was to measure the resistance of insertion of a dental implant screw designed based on norm, made of the alloy Ti6Al4V [1], which was designed for the cancellous bone density (BD) molar region of the human jaw. The implants were embedded in the in a simulated bone polymer (Sawbone®) [2] and were compared with specimens of the region molar of human jaw cadaver [3]. Using a digital torque wrench, the values of the insertion torque (IT) were calculated in the specimens with the implants inserted [4]. The minimum measured value was 25 Ncm or 0.25 Nm and the density of the maximum torque value measured was 110 Ncm or 1.1 in Nm recorded in the cadaver jawbone. The Pull Out Test (POT) was then carried out in order to determine the resistance of the insertion implant at the bone interface. The experimental results obtained for density, IT and resistance to insertion were then compared in order to determine the strength of fixation of the implant to the bone interface.
Physical Properties of Thin Films of GaAs and AlxGa1-xAs Grown by Solid-Arsenic-Based MOCVD
Authors: Castillo-Ojeda Roberto , Díaz-Reyes Joel , Galván-Arellano Miguel , Peña-Sierra Ramon
Published: June 2014

We have studied the optical properties of GaAs and AlxGa1-xAs thin films using low-temperature photoluminescence and Fourier transform infrared spectroscopy. The GaAs and its alloys were grown by MOCVD using solid arsenic instead of arsine, as the arsenic precursor. The gallium and aluminium precursors were trimethylgallium (TMGa) and trimethylaluminium (TMAl), respectively. Some difficulties for growing AlxGa1-xAs by solid-arsenic-based MOCVD system are the composition homogeneity of the layers and the oxygen and carbon incorporation during the growth process. The composition homogeneity of the films was evaluated by low-temperature photoluminescence. Infrared measurements on the samples allowed the identification of the residual impurities, which are carbon-substitutional, Ga2O3, molecular oxygen, humidity and two unidentified impurities. Samples grown at temperatures lower than 750°C were highly resistive, independently of the ratio V/III used; the samples grown at higher temperatures were n-type, as it was proved by Hall effect measurements.