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Articles 4351 - 4380 of 5701

Full-Text Articles in Engineering

An Investigative Study Of Patents From An Engineering Design Perspective, Ajit Singh Kanda Jul 2008

An Investigative Study Of Patents From An Engineering Design Perspective, Ajit Singh Kanda

All Theses

Preservation and reuse of valuable design experience aids in the design of new products and processes. Product design repositories are presently being used as a means to preserve and later reuse design knowledge. As such, patent databases such as the United States Patent office and the European Patent Office offer design knowledge in the form of patents. Unfortunately, these sources of novel design solutions do not appear to have been have not been effectively used in the context of engineering design.
In this research, the role of patents in a systematic design process is reviewed understand its utility in the …

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Design Process Modeling: Towards An Ontology Of Engineering Design Activities, Pavan Kumar Jul 2008

Design Process Modeling: Towards An Ontology Of Engineering Design Activities, Pavan Kumar

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An ontology of engineering design activities, called the Design Activity Ontology (DAO), is developed in this research. The DAO models 82 information flows and 25 design activities. These activities cover phases of the design process from conceptual phase through detail design phase. The ontology provides a formalized and structured vocabulary of design activities for consistency and exchange of design process models. The DAO enables design processes to be modeled, analyzed and optimized. The DAO is constructed using information flows identified in current design literature, commonly accepted engineering design textbooks, and an existing activity ontology. Specifically, the DAO is an extension …

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Electrokinetic Transport In Micro- And Nano- Channels:A Study Examining Electrokinetic Energy Conversion And Dielectrophoretic Particle Separation, Christian Davidson Jul 2008

Electrokinetic Transport In Micro- And Nano- Channels:A Study Examining Electrokinetic Energy Conversion And Dielectrophoretic Particle Separation, Christian Davidson

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New micro-fabrication techniques have allowed for the recent development of micro-scale lab on a chip devices which can be utilized for on chip biological analysis as well as electrokinetic energy conversion. This thesis aims to theoretically examine the current thermodynamic efficiency discrepancies in electrokinetic energy conversion devices as well as explore the potential for efficiency increase in a device which supports fluid slip. Also, a micro-fluidic lab on a chip device is fabricated and demonstrated to be capable of continuously separating multiple particles of 1μm, 5μm and 10μm out of a bulk solution. Our device employs a DC dielectrophoretic technique, …

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Estimation Of Vehicle Mass And Road Grade, Tejas Ghotikar Jul 2008

Estimation Of Vehicle Mass And Road Grade, Tejas Ghotikar

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This thesis describes development of a real-time-implementable algorithm for simultaneous estimation of a heavy vehicle's mass and time-varying road grade and its verification with experimental data. Accurate estimate of a heavy vehicle's mass is critical in several vehicle control functions such as in transmission and stability control. The goal is to utilize the standard signals on a vehicle in a model-based estimation strategy, as opposed to a more costly sensor-based approach. The challenge is that unknown road grade complicates model-based estimation of vehicle mass and therefore the time-varying grade should be estimated simultaneously. In addition an estimate of road grade …

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Flow Boiling Of Acetone In Parallel Rectangular Mini-Channels, Rafael Zimmermann Jul 2008

Flow Boiling Of Acetone In Parallel Rectangular Mini-Channels, Rafael Zimmermann

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Recent miniaturization of cooling systems has demanded better designing tools for compact heat exchangers. Forced two-phase flow through small channels is an effective way to better performance in a limited space. However, the characteristics of flow boiling in small channels differ from those in regular size channels, prompting a need for better understanding and development of predictive tools.
The characteristics of flow boiling in compact heat exchangers with parallel rectangular mini-channels of cross sections 0.50 x 0.50 mm, 0.75 x 0.75 mm, 1.00 x 1.00 mm, and 1.50 x 1.50 mm were experimentally investigated. Acetone was the fluid of choice, …

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Stability Analysis And Decentralized Control Of Coupled Oscillators With Feedback Delays, Saurabh Keni Jul 2008

Stability Analysis And Decentralized Control Of Coupled Oscillators With Feedback Delays, Saurabh Keni

All Theses

Most dynamic systems do not react instantaneously to actuation signals. The temporal evolution of some others is based on retarded communications or depends on information from the past. In such cases, the mathematical models used to describe these systems must include information about the past dynamics of the states. These models are often referred to as delay or retarded systems. Delays could channel energy in and out of a system at incorrect time intervals producing instabilities and rendering controllers' performance ineffective.
The purpose of this research is two folds. The first investigates the effect of inherent system delays on the …

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Topology And Free-Size Optimization With Multiple Loading Conditions For Light Weight Design Of Die Cast Automotive Backrest Frame, Sreeram Polavarapu Jul 2008

Topology And Free-Size Optimization With Multiple Loading Conditions For Light Weight Design Of Die Cast Automotive Backrest Frame, Sreeram Polavarapu

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Automotive seats provide comfort and safety to the occupant travelling in the vehicle. An optimized seat design should be aesthetically pleasing, lightweight and meet the safety requirements. An automotive seat with occupant is subjected to various kinds of forces in the event of crash and should be designed for strength and stiffness as measured by stress and strain, and deflection. In this work, finite element analysis, together with topology and free-size optimization is used to design a lightweight die cast automotive front seat backrest frame when subjected to loads prescribed by ECE R17 European government regulations and additional loads which …

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Computational Analysis Of Feasibility And Utility Of Direct-Adhesion Polymer-To-Metal Hybrid Technologies For Use In Load Bearing Body-In-White Automotive Components, Vijay Sellappan Jul 2008

Computational Analysis Of Feasibility And Utility Of Direct-Adhesion Polymer-To-Metal Hybrid Technologies For Use In Load Bearing Body-In-White Automotive Components, Vijay Sellappan

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Traditionally, metals and plastics are fierce competitors in many automotive engineering applications. This paradigm is gradually being abolished as the polymer-metal-hybrid (PMH) technologies, developed over the last decade, are finding ways to take full advantage of the two classes of materials by combining them into a singular component/sub-assembly. By employing one of the several patented PMH technologies, automotive original equipment manufacturers (OEMs) have succeeded in engaging flexible assembly strategies, decreasing capital expenditures and reducing labor required for vehicle manufacture. The basic concept utilized in all PMH technologies is based on the fact that while an open-channel thin-wall sheet-metal component can …

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Compliant Multi-Link Vehicle Suspensions, Souharda Raghavendra Jul 2008

Compliant Multi-Link Vehicle Suspensions, Souharda Raghavendra

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One of the goals of automotive lightweight engineering is to achieve reduction in mass, cost, and complexity of vehicle components, subsystems and systems without sacrificing functionality and expected performance. This thesis addresses functionally integrated suspension systems that could lead to reduction in part count and mass and save packaging space. It deals with the analysis of multi-link suspensions that combine the function of energy storage and the mechanism of wheel location and guidance within individual compliant links and members.
To explore possibilities, a generic kinematic model of an independent five-link suspension was built in the MSC.ADAMS multi-body dynamics simulation environment. …

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Synthesis And Electrochemical Characteristics Of Li[Li(0.167)Mn(0.583)Ni(0.25)]O2 Cathode Material, Ling-Yan Yu, Wei-Hua Qiu, Fang Lian, Jia-Yuan Huang, Xao-Li Kang, Wei Liu May 2008

Synthesis And Electrochemical Characteristics Of Li[Li(0.167)Mn(0.583)Ni(0.25)]O2 Cathode Material, Ling-Yan Yu, Wei-Hua Qiu, Fang Lian, Jia-Yuan Huang, Xao-Li Kang, Wei Liu

Journal of Electrochemistry

The cathode material of Li[Li0.167Mn0.583Ni0.25]O2 was synthesized by low-heat solid state reaction.The results of XRD and FESEM indicated that the powders of the material were well crystallized with the uniform diameters ranging from 60 nm to 100 nm and could be indexed as α-NaFeO2 structure(R3-m space). Galvanostatic charge-discharge tests showed that the electrode delivered the capacity of about 120 mAh/g with good cyclability when cycled in 2.5~4.4V at 0.5C. When the cut-off potential was set up to 4.6V, the cathode delivered much larger capacities with the maximum of 234 mAh/g. It was …

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Performance Of Air Breathing Direct Methanol Fuel Cell Under Ambient Condition, Jian-Guo Liu, Jun Gu, Tao Yu, Zhi-Gang Zou, T.S Zhao May 2008

Performance Of Air Breathing Direct Methanol Fuel Cell Under Ambient Condition, Jian-Guo Liu, Jun Gu, Tao Yu, Zhi-Gang Zou, T.S Zhao

Journal of Electrochemistry

The performance of the passive DMFC was systematically investigated under an ambient condition by simulating a wide range of temperature and humidity in a high-quality environmentally controlled room.The results indicated that the performance of the passive DMFC was nearly independent of ambient humidity from 30% to 90% RH and water produced in the cathode was expelled mostly from the cell in a liquid state.Compared with the humidity,the ambient temperature has a significant effect on the performance of the passive DMFC.The power density of 30 mW·cm-2 were obtained at 40℃,while only 10 mW·cm-2 at 10 ℃.

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Structure And Property Of Molecular Self-Assembled Membrane With Zirconium Ion, Tian-De Wang, Rong Wang, Xia-Qin Wu, Zhi-Gang Guo, Wei-Wei Ji May 2008

Structure And Property Of Molecular Self-Assembled Membrane With Zirconium Ion, Tian-De Wang, Rong Wang, Xia-Qin Wu, Zhi-Gang Guo, Wei-Wei Ji

Journal of Electrochemistry

According to the complex interaction between dodecyl phosphonate and stainless steel surface as well as the zirconium ion,the self-assembled monolayer and double-layer dodecyl phosphonate modified 304 type stainless steel electrode were prepared.The electrodes were characteristiced by static contact angles and electrochemical polarization methods.The results suggested that the double-layer modified stainless steel electrode had better corrosion inhibition effect than the monolayer modified electrode.

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Electrodeposition Of Sol-Gel Imprinted Films Modified Electrode And Its Application For 3,4-Dihydroxybenzoic Acids Determination, Gui-Lin Wang, Rong Wang, Xia-Qin Wu, Zong-Rang Zhang May 2008

Electrodeposition Of Sol-Gel Imprinted Films Modified Electrode And Its Application For 3,4-Dihydroxybenzoic Acids Determination, Gui-Lin Wang, Rong Wang, Xia-Qin Wu, Zong-Rang Zhang

Journal of Electrochemistry

The sol-gel molecularly imprinted films modified glassy carbon electrode was prepared by electrodeposition of tetramethoxysilane(TMOS) and phenyltrimethoxysilane(PTMOS) with chronoamperometry in the presence of template molecules 3,4-dihydroxybenzoic acid(3,4-DHBA) followed by extraction with ethanol.The modified electrode could successfully avoid the polymerization of oxidized 3,4-DHBA and the interference of 2,4-DHBA.A linear concentration response curve was obtained from 1.0 × 10-5 mol·L-1 to 8.0×10-4 mol·L-1,with the detected concentration limit of 5.0 × 10-6 mol·L-1.

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Electrochemical Performances Of Copper/Activated Carbon Composites, Lan-Ting Li, Qiang Xie, Wen Yan, Yan-Yan Wang, Wen-Wen Xing May 2008

Electrochemical Performances Of Copper/Activated Carbon Composites, Lan-Ting Li, Qiang Xie, Wen Yan, Yan-Yan Wang, Wen-Wen Xing

Journal of Electrochemistry

The development and improvement of electrode materials can result in the enhancement of the performances of electrochemical capacitor.In this paper various copper/activated carbon composites were prepared in the presence of different amounts(from 0% to 40%) of copper nitrate from bituminous coal.Then different electrodes were prepared from copper oxide,activated carbon and copper/activated carbon composites,respectively,and were characterized by cyclic voltammetry,alternative current(AC) impedance,charge-discharge at constant current and maintenance of the self-potential.The results showed that the proper amount of copper in copper/activated carbon composites positively influenced the electrochemical performances of electrodes,and the capacitance of copper/activated carbon composites was larger than that of the total …

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Preparation Of Zn-Ni Alloy Whisker By Electrochemical Method, Zhen-Hai Liang, Xi-Hua Xia May 2008

Preparation Of Zn-Ni Alloy Whisker By Electrochemical Method, Zhen-Hai Liang, Xi-Hua Xia

Journal of Electrochemistry

The Zn-Ni alloy whiskers were prepared by electrochemical method and were characterized by XRD, SEM and EDS methods. The results showed that Ni5Zn21 and Ni3Zn22 whiskers were obtained with the length of 2~4 μm and the diameter of 250 nm, thereby the rations of length/diameter fell between 8 and 16. The electrochemical behavior was investigated by cyclic voltammetry method simultaneously. A new method was provided on whisker preparation based on this work.

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Carbon Nanotube Array Electrodes Based Supercapacitors With 3.5v Working Voltage, Hao Zhang, Gao-Ping Cao, Yu-Sheng Yang, Zhen-Nan Gu, Bin Xu, Wen-Feng Zhang May 2008

Carbon Nanotube Array Electrodes Based Supercapacitors With 3.5v Working Voltage, Hao Zhang, Gao-Ping Cao, Yu-Sheng Yang, Zhen-Nan Gu, Bin Xu, Wen-Feng Zhang

Journal of Electrochemistry

The carbon nanotube arrays(CNTA) were grown directly on the substrates of Ta and stainless steel by chemical vapor deposition.The button-like supercapacitors were fabricated based the CNTA electrodes.The electrochemical performance of CNTA based supercapacitors presentsed high working voltage(3.5 V),long cycle life,and good rate capability.The power and energy densities are were 928 kW·kg-1 and 19 Wh·kg-1,respectively(based on the mass of CNTA).

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Direct Electrochemistry Of God On Glassy Carbon Electrode Modified With Mesoporous Carbon, Kun-Qi Wang, Lin Zhu, Wei Xing May 2008

Direct Electrochemistry Of God On Glassy Carbon Electrode Modified With Mesoporous Carbon, Kun-Qi Wang, Lin Zhu, Wei Xing

Journal of Electrochemistry

Glucose oxidase(GOD) is immobilized on glassy carbon electrode mesoporous carbon by simple method.Cyclic voltammetric results indicated that on GOD of the modified electrode a quasi-reversible redox reaction took place(GCE) surface modified at a formal potential of-0.4294 V in 0.1 mol/L phosphate buffer solution(PBS)(pH 7.1).The electrochemical reaction consisted of a two-electron transfer coupled with a two-proton transfer.The GOD can completely catalyze oxidation of glucose via electron transfer intermedia of ferrocene monocarboxylic acid(FMCA) in saturated solutions with N2.The bioactivity of GOD on the modified electrode with mesoporous carbon was obviously unattacked.

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Electroless-Deposition Synthesis Of Highly Active Ptru/C And Ptrusn/C As Anode Catalysts For Defc, Jing Zhu, Yi Su, Hua Ma, Fang-Yi Cheng, Zhan-Liang Tao, Jing Liang, Jun Chen May 2008

Electroless-Deposition Synthesis Of Highly Active Ptru/C And Ptrusn/C As Anode Catalysts For Defc, Jing Zhu, Yi Su, Hua Ma, Fang-Yi Cheng, Zhan-Liang Tao, Jing Liang, Jun Chen

Journal of Electrochemistry

In this paper,the preparation,characterization,and ethanol electrocatalytic oxidation of Pt0.5Ru0.5/C and Pt0.5Ru0.15Sn0.35/C electrocatalysts were reported.The electroless-deposition with sensitization-activation pretreatment was applied to prepare Pt0.5Ru0.5/C and Pt0.5Ru0.15Sn0.35/C electrocatalysts. The XRD and TEM analyses showed that the as-prepared catalysts were composed of well-dispersed PtRu or PtRuSn nanoparticles with an average particle size of about 3 nm.The electrochemical measurements demonstrated that the as-prepared Pt0.5Ru0.5/C and Pt0.5Ru0.15Sn0.35/C catalysts exhibited much enhanced peak current density for …

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Electrocatalytic Performance Of Pt/C And Pt/Wo3/C Catalysts For Methanol Oxidation, Yuan-Yuan Chu, Bing Wu, Ya-Wen Tang, Tian-Hong Lu, Ying Gao May 2008

Electrocatalytic Performance Of Pt/C And Pt/Wo3/C Catalysts For Methanol Oxidation, Yuan-Yuan Chu, Bing Wu, Ya-Wen Tang, Tian-Hong Lu, Ying Gao

Journal of Electrochemistry

The catalysts of Carbon supported Pt(Pt/C) and carbon supported Pt/WO3(Pt/WO3/C) were prepared with liquid phase reduction method.It was found that the catalytic activity and stability of the Pt/WO3/C catalysts were increased with the addition of WO3.When the atomic ratio of Pt and W was 1∶1,the best electrocatalytic performance of the Pt/WO3/C catalyst for the methanol oxidation was obtained.This is attributed to the larger electrochemical surface area of Pt/WO3/C and the weeker adsorption of CO towards the catalyst.

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Preparation And Electrochemical Capacitance Of Spherical-Like Polypyrrole Doped With Heparin Sodium, Hong-Yu Mi, Xiao-Gang Zhang, Su-Dong Yang, Xiang-Guo Ye May 2008

Preparation And Electrochemical Capacitance Of Spherical-Like Polypyrrole Doped With Heparin Sodium, Hong-Yu Mi, Xiao-Gang Zhang, Su-Dong Yang, Xiang-Guo Ye

Journal of Electrochemistry

Spherical-like polypyrrole with an average diameter of 100 nm as the electrode material for supercapacitor was prepared by a self-assembly process with heparin sodium salt as the dopant at-10 ℃.The morphology and electrochemical properties were characterized by transmission electron microscopy(TEM),cyclic voltammetry(CV),galvanostatic charge/discharge and electrochemical impedance spectroscopy(EIS) measurements.The results showed that the polypyrrole doped with heparin sodium salt exhibited good capacitive behavior.The specific capacitance of single electrode was up to 338 F/g at 3 mA/cm2.

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Synthesis Of Agv3O8 As High-Capacity Of Cathode Materials For Lithium Secondary Batteries Via A Soft Chemistry Technique, Xiao-Yu Cao, Tao Li, Ling-Ling Xie, Xiang-Yang Yan, Chi-Wei Wang May 2008

Synthesis Of Agv3O8 As High-Capacity Of Cathode Materials For Lithium Secondary Batteries Via A Soft Chemistry Technique, Xiao-Yu Cao, Tao Li, Ling-Ling Xie, Xiang-Yang Yan, Chi-Wei Wang

Journal of Electrochemistry

The layered cathode material of AgV3O8 has been prepared for the lithium secondary batteries via the soft chemistry technique. The so-synthesized powders were characterized by XRD(powder X-ray diffraction), SEM(scanning electron microscope) and LPSA(laser particle size analysis). The electrochemical property was investigated by the galvanostatic discharge-charge technique. The results indicated that the particale sizes of AgV3O8 prepared were small in the distribution of narrow range, which leads to high discharge capacity. Among them, the material synthesized at 400 ℃ displayed the first discharge capacity of 760.5 mAh/g.

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Passivation Behaviors Of Mo, W Electrodes In Mgcl2-Kcl-Nacl-Cacl2 Molten Salt For Electrolysis Of Magnesium, Ye Chen, Ke Ye May 2008

Passivation Behaviors Of Mo, W Electrodes In Mgcl2-Kcl-Nacl-Cacl2 Molten Salt For Electrolysis Of Magnesium, Ye Chen, Ke Ye

Journal of Electrochemistry

The discharge process and passivation behaviors of Mg(Ⅱ) on cathode(Mo, W) in MgCl2-KCl-NaCl-CaCl2 molten salt system had been investigated by means of cyclic voltammetry and chronoamperometry. The composition of molten salt was MgCl(10%) + CaCl(20%) + NaCl(60%) + KCl(10%)(by mass) and the temperature of electrolysis was 725 ℃. The deposition potential of Mo was 37 mV more negative than that of W, while the peak current was sharper than Mo according to the voltammograms at 0.05 V/s, indicating that the passivation on Mo cathode is easier than W. The formation of MgO impurities during the electrolysis could …

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The Effect Of Annealed Temperature On Properties Of Ru-Ir-Sn Oxide Anode Coatings, Lei Ji, Jun-Tao Wang, Li-Kun Xu, Wen-Bin Liu, Gui-Lin Xue May 2008

The Effect Of Annealed Temperature On Properties Of Ru-Ir-Sn Oxide Anode Coatings, Lei Ji, Jun-Tao Wang, Li-Kun Xu, Wen-Bin Liu, Gui-Lin Xue

Journal of Electrochemistry

The anode coatings of Ru-Ir-Sn oxide were prepared by sol-gel method with different annealed temperatures.The influences of annealed temperature in properties of anode coatings were characterized by scanning electron microscope(SEM),energy dispersive X-ray detector(EDX),X-ray diffraction(XRD),potential of chlorine evolution,accelerated life,cyclic voltammetry and electrochemical impedance spectroscopy(EIS) tests.The results showed that the annealed temperature affected the morphology of coatings,while the electric quantities of cyclic voltammetry and double layer capacitances of anode coatings had a tendency to fall down and the potential of chlorine evolution and accelerated life had a tendency to increase as the annealed temperature increased.

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Preparation And Photoelectrochemical Properties Of Fe-Doped Tio2 Nanotube Arrays, Jing Li, Lan Sun, Hui-Fang Zhuang, Cheng-Lin Wang, Rong-Gui Du, Chang-Jian Lin May 2008

Preparation And Photoelectrochemical Properties Of Fe-Doped Tio2 Nanotube Arrays, Jing Li, Lan Sun, Hui-Fang Zhuang, Cheng-Lin Wang, Rong-Gui Du, Chang-Jian Lin

Journal of Electrochemistry

The Fe-doped TiO2 nanotube arrays were fabricated in Fe(NO3)3-HF mixing solutions by electrochemical anodic oxidation method,and characterized by FESEM,Raman,XPS and DRS.The effect of Fe concentratiions on photoelectrochemical property of the arrays was also investigated.The diameters and lengths of Fe-doped TiO2 nanotube arrays were 50~90 nm and about 200 nm,respectively.Compared with the undoped TiO2 nanotube arrays,the absorption edge of Fe-doped TiO2 nanotube arrays appeared red shifting.The more Fe content,the larger red shifting,in addition,the photocurrent of Fe-doped TiO2 nanotube arrays increased obviously.

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Cyclic Voltammetry And In Situ Ftir Studies Of Cyanide Adsorption On Nanostructured Au Film Electrode In Alkaline Solutions, Chun-Hua Zhen, Chun-Jie Fan, Shi-Gang Sun May 2008

Cyclic Voltammetry And In Situ Ftir Studies Of Cyanide Adsorption On Nanostructured Au Film Electrode In Alkaline Solutions, Chun-Hua Zhen, Chun-Jie Fan, Shi-Gang Sun

Journal of Electrochemistry

The adsorption of cyanide(CN-) on electrodes of nanometer scale thin film of gold supported on glassy carbon(nm-Au/GC) in alkaline solutions were investigated using cyclic voltammetry and in situ FTIR spectroscopy.It has revealed that the electrodeposited nanostructured Au thin film exhibited AIREs(abnormal infrared effects) for CN-adsorption,which manifested 3 nonlinear IR spectral features: inversion of the direction of CN-band,enhancement of IR absorption of adsorbed CN-species(about 39.2 folds) and increase in the FWHM(full width at half maximum) of CN-band.

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Quick Tester With Usb Interface For The Corrosion Protection Properties Of Organic Coating, Xiang-Dong Zhuo, Chang-Jian Lin May 2008

Quick Tester With Usb Interface For The Corrosion Protection Properties Of Organic Coating, Xiang-Dong Zhuo, Chang-Jian Lin

Journal of Electrochemistry

According to the principle of multiple dynamic potential scaning polarization,a quick tester with USB interface for the fast study of corrosion resistance properties of organic coating/ metal system has been developed.This tester is portable,facile,practical,and has a strong function for data collection and data treatment.It is not only suitable for the accelerated test in laboratory,but also for the quick test and evaluation to the corrosion resistance of the organic coating/metal system in industrial spots.

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Real-Time Power Management Of A Fuel Cell/Ultracapacitor Hybrid, Wesley Greenwell May 2008

Real-Time Power Management Of A Fuel Cell/Ultracapacitor Hybrid, Wesley Greenwell

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This thesis presents the system architecture design, system integration methodology, and real-time control of a fuel cell/ultracapacitor hybrid power system. The main objective is for the hybrid system to respond to real-world fluctuations in power without negatively impacting fuel cell life.
A Proton Exchange Membrane (PEM) Fuel Cell is an electrochemical device which converts the chemical energy of pure hydrogen into electricity through a chemical reaction with oxygen. The high conversion efficiency, zero harmful emissions, high power-to-weight ratio, scalability, and low temperature operation make PEM fuel cells very attractive for stationary and portable power applications. However, fuel cells are limited …

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Computational Method For Solving Spoke Dynamics On High Speed Rolling Tweel, Kranti Kiran Manga May 2008

Computational Method For Solving Spoke Dynamics On High Speed Rolling Tweel, Kranti Kiran Manga

All Theses

Extensive studies have been conducted in the past to show that the characteristics of a non-pneumatic structure, the TweelTM are the same as the pneumatic tires. These characteristics include low contact pressure, low stiffness, low energy loss from obstacle impacts, low mass, and high load-carrying capacity. The TweelTM consists of a ring shaped shear beam comprised of two inextensible membranes separated by a relatively low modulus elastic material. This shear beam is connected to the hub by thin elastic spokes.
When used for high speed rolling applications, the TweelTM produces unacceptably high levels of acoustic noise. It has been suggested …

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Random Road Analysis And Improved Gear Ratio Selection Of A Front Wheel Drive Drag Racing Car, Thomas New May 2008

Random Road Analysis And Improved Gear Ratio Selection Of A Front Wheel Drive Drag Racing Car, Thomas New

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Drag racing has been around since the 1950's and has become a very popular and very competitive sport. The difference between winning and losing can be hundredths and even thousandths of a second. Drag racing teams need every advantage they can get in order to excel in their field. On-track testing is very expensive and can consume large amounts of time and resources that a race team may not be able to afford.
One way to address this potential problem of high cost is by using computer simulation to show how your drag race car may perform at different tracks …

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Ductile-Regime Machining Of Glass Using The Micromilling Process, Kevin Foy May 2008

Ductile-Regime Machining Of Glass Using The Micromilling Process, Kevin Foy

All Theses

Glass is a homogeneous material with amorphous crystal structure that is produced through the rapid cooling of its molten state below the glass transition temperature. Glass exhibits many excellent mechanical and physical properties, and it is widely used in automotive, communications, optics, electronics, architectural, and biomedical industries. For certain applications such as DNA microarrays, glass components with microfeatures are typically produced using a combination of photolithography and etching processes, which is generally time consuming and can involve hazardous chemicals. It would be ideal to fabricate some glass devices through mechanical micromachining for some rapid prototyping applications of glass-based devices, but …

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