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2006

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Articles 31 - 60 of 853

Full-Text Articles in Electrical and Computer Engineering

Numerical Analysis Of Sandwiched Composite-Fss Structures, Qiang Rui, Chen Ji, Huang Jingyu, Maria Koledintseva, Richard E. Dubroff, James L. Drewniak, Yang Fan Dec 2006

Numerical Analysis Of Sandwiched Composite-Fss Structures, Qiang Rui, Chen Ji, Huang Jingyu, Maria Koledintseva, Richard E. Dubroff, James L. Drewniak, Yang Fan

Electrical and Computer Engineering Faculty Research & Creative Works

A numerical technique to analyze shielding effectiveness of sandwiched FSS-composite structures is proposed. This technique is based on using a dispersive FDTD method in conjuncture with a novel periodic boundary condition to model sandwiched FSS-composite elements. Results show that by inserting single or multilayered FSS elements into composite materials, better shielding effectiveness can be achieved. © 2006 IEEE.

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Generation Planning And Market Operation Strategies In The Southwest Power Pool Energy Imbalance Service Market, Kittipong Methaprayoon Dec 2006

Generation Planning And Market Operation Strategies In The Southwest Power Pool Energy Imbalance Service Market, Kittipong Methaprayoon

Electrical Engineering Dissertations - Archive

The transition of the Southwest Power Pool (SPP) from its traditional operation under tariff towards the new market environment has significant impact on the utilities in the SPP footprint, both in terms of planning and operations. The new market regulation creates the need for the utilities to reassess their planning strategy, primarily to ensure that operational decisions conform to the new market rules while remain profitable under the new operating regime. The utilities are referred to as Market Participants (MP) under the new market scheme. The new market environment will expose the MPs to a large amount of information with …

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Fiber Optic Scanner Using Electromagnetic Actuation With Different Ferromagnetic Materials, Pratibha C. Phuyal Dec 2006

Fiber Optic Scanner Using Electromagnetic Actuation With Different Ferromagnetic Materials, Pratibha C. Phuyal

Electrical Engineering Theses - Archive

A fiber optic scanner capable of scanning medical imaging actuated by an external magnetic field is designed and characterized using different magnetized and non magnetized ferromagnetic materials. Cobalt, Iron, Nickel, and Samarium Cobalt powders were used before and after magnetization to perform the actuation. Plastic optical fiber and a silica optical fiber are coated with 70 % enamel paint with 30 % different ferromagnetic materials mixed using brush. Due the low Young's Modulus, the plastic optical fiber could not actuate like silica optical fiber. Therefore, the silica fiber was used to conduct the experiments. The static and dynamic measurements were …

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Neural Network Solution For Fixed-Final Time Optimal Control Of Nonlinear Systems, Tao Cheng Dec 2006

Neural Network Solution For Fixed-Final Time Optimal Control Of Nonlinear Systems, Tao Cheng

Electrical Engineering Dissertations - Archive

In this research, practical methods for the design of H2 and H-Infinity optimal state feedback controllers for unconstrained and constrained input systems are proposed. The dynamic programming principle is used along with special quasi-norms to derive the structure of both the saturated and optimal controllers in feedback strategy form. The resulting Hamilton-Jacobi-Bellman (HJB) and Hamilton-Jacobi-Isaacs (HJI) equations are derived respectively. Neural networks are used along with the least-squares method to solve the Hamilton-Jacobi differential equations in the H2 case, and the cost and disturbance in the H-Infinity case. The result is a neural network unconstrained or constrained feedback controller that …

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Performance Analysis And Design Of Space-Time Codes, Chen Liao Dec 2006

Performance Analysis And Design Of Space-Time Codes, Chen Liao

Electrical Engineering Dissertations - Archive

In this dissertation, performance and design of space-time codes have been studied. The main objective of this dissertation has been to improve the performance of space-time codes. This dissertation covers a wide range of topics in space-time codes. It involves theoretical analysis, design, and implementation for space-time trellis codes, space-time turbo codes, and orthogonal space-time codes. We begin with the study of performance analysis of upper bound of pair-wise error probability (PEP) and exact PEP. The exact PEP is derived using a straightforward method. The exact PEP provides a better understanding of the performance behavior to the other range of …

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Dynamic Stability Analysis Of Large-Scale Power Systems Using A Fast Investigation Method, Ming-Tse Kuo Dec 2006

Dynamic Stability Analysis Of Large-Scale Power Systems Using A Fast Investigation Method, Ming-Tse Kuo

Electrical Engineering Dissertations - Archive

Following power market deregulation and the proposed standard market design, the activities of cross boundary power transactions are increased significantly. Traditional company based stability analysis can not satisfy today's operating environment. However, simulating the entire interconnection power system may exceed the capacity of existing commercial stability analysis software. Fortunately, most of the stability problems are started from the local level. One will be able to avoid most of the system wide stability issues by mitigating the problems in the early stage. Based on eigenvector decompositions of the Jacobian, this dissertation proposes a new algorithm for performing the dynamic stability problem …

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Fabrication, Characterization And Hall Mobility Analysis Of Mos Devices With Low-K And High-K Dielectric Materials, Rakshit Agrawal Dec 2006

Fabrication, Characterization And Hall Mobility Analysis Of Mos Devices With Low-K And High-K Dielectric Materials, Rakshit Agrawal

Electrical Engineering Theses - Archive

Scaling of MOSFETS has led to leakage current problems in SiO2 dielectric based MOSFETS. This has led to the introduction of high-k dielectric materials which can afford greater physical thickness and achieve the same capacitance with lesser equivalent oxide thickness. But the high-k devices have certain limitations like channel mobility degradation. Mobility degradation in high-k MISFETS is discussed in this work using Hall measurements. The MOS devices were fabricated with SiO2 and HfSiO, on p-type silicon substrate. The fabrication process flow used for both type of MOS devices is explained. Characterization and analysis was performed for the determination of various …

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Machine Learning For Computer Security, Philip K. Chan, Richard P. Lippmann Dec 2006

Machine Learning For Computer Security, Philip K. Chan, Richard P. Lippmann

Electrical Engineering and Computer Science Faculty Publications

The prevalent use of computers and internet has enhanced the quality of life for many people, but it has also attracted undesired attempts to undermine these systems. This special topic contains several research studies on how machine learning algorithms can help improve the security of computer systems.

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Arribot- An Enabler For Studying Mobile Wireless Sensor Networks, Jaymala Suresh Ghadigaonkar Dec 2006

Arribot- An Enabler For Studying Mobile Wireless Sensor Networks, Jaymala Suresh Ghadigaonkar

Electrical Engineering Theses - Archive

The objective of this thesis is to structure a mobile wireless sensor network using low cost, custom made robotic platforms. Over the years, several projects have proved that the performance of a static wireless sensor network (WSN) is greatly enhanced by using mobile WSN for applications like adaptive exploration or in search and rescue missions where the network topology changes with changes in the environment. A low cost, mobile wireless sensor node known as the ARRI BOT has been designed to contribute along with other robotic platforms in structuring an ingenious mobile wireless sensor network (MSWN). The ARRI BOT has …

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Physical Layer And Application Layer Issues Of Wireless Sensor Networks, Lingming Wang Dec 2006

Physical Layer And Application Layer Issues Of Wireless Sensor Networks, Lingming Wang

Electrical Engineering Dissertations - Archive

The potential for collaborative, robust networks of wireless sensors has attracted a great deal of research attention. For the most part, this is due to the compelling applications that wireless sensor networks will enable. Location sensing, environmental observation and surveillance, medical monitoring and a lot other applications are all gaining interest. However, wireless sensor network poses a large number of challenges. Among all, one of the most important challenges is design sensor networks that have long network lifetime, which will become especially difficult due to the energy-constrained nature of the sensor nodes. In this thesis, we focus on physical and …

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Novel Capacitance Extraction Method Using Direct Boundary Integral Equation Method And Hierarchical Approach, L. (Lijun) J. Jiang, B. J. Rubin, J. D. Morsey, H. T. Hu, A. Elfadel Dec 2006

Novel Capacitance Extraction Method Using Direct Boundary Integral Equation Method And Hierarchical Approach, L. (Lijun) J. Jiang, B. J. Rubin, J. D. Morsey, H. T. Hu, A. Elfadel

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel hierarchical capacitance extraction method is introduced. It takes advantage of surface integral equations to have far less unknowns than the volumetric method. It uses the "divide and conquer" strategy to hierarchically solve the dense capacitance matrix efficiently. It partitions the problem into small regions (cells) automatically and each region is analyzed separately. An inverse binary-tree browse procedure is employed to combine cell capacitance matrixes from leafy level of the tree to the root. A global capacitance matrix is obtained at the root without computing charge distribution. Benchmarks using the developed code CSurf are provided to …

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The Use Of Fast Integral Equations Solvers For Practical Package And Interconnect Analysis, J. D. Morsey, B. J. Rubin, L. (Lijun) Jiang, L. Shan, L. B. Eisenberg, D. Becker, M. Arseneault Dec 2006

The Use Of Fast Integral Equations Solvers For Practical Package And Interconnect Analysis, J. D. Morsey, B. J. Rubin, L. (Lijun) Jiang, L. Shan, L. B. Eisenberg, D. Becker, M. Arseneault

Electrical and Computer Engineering Faculty Research & Creative Works

Fast integral equation methods are now being applied to packaging and other such "low frequency" problems. This paper explores some of the issues surrounding such an application to real, product level packaging and interconnect type structures. Discussed are issues such as low frequency breakdown, mesh aspect ratios, and solver convergence. Finally, integral equation solver examples are presented using the IBM internally developed pre-corrected FFT (PFFT) solver labeled EMSurf[l]. ©2006 IEEE.

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Integral Equation Solvers For Real World Applications -Some Challenge Problems, W. C. Chew, I. T. Chiang, C. P. Davis, A. Hesford, M. K. Li, Y. Liu, Z. G. Qian, M. Saville, L. Sun, M. S. Tong, J. Xiong, L. (Lijun) J. Jiang, H. Y. Chao, Y. H. Chu Dec 2006

Integral Equation Solvers For Real World Applications -Some Challenge Problems, W. C. Chew, I. T. Chiang, C. P. Davis, A. Hesford, M. K. Li, Y. Liu, Z. G. Qian, M. Saville, L. Sun, M. S. Tong, J. Xiong, L. (Lijun) J. Jiang, H. Y. Chao, Y. H. Chu

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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Monitoring The True Harmonic Current Of A Variable Speed Drive Under Nonsinusoidal Supply Conditions, J. Mazumdar, R. Harley, F. Lambert, T. Habetler, Ganesh K. Venayagamoorthy Dec 2006

Monitoring The True Harmonic Current Of A Variable Speed Drive Under Nonsinusoidal Supply Conditions, J. Mazumdar, R. Harley, F. Lambert, T. Habetler, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The increased use of nonlinear devices in industry has resulted in direct increase of harmonic distortion in the industrial power system. Variable speed drives are an example. with the widespread proliferation of nonlinear loads in a power distribution network, the voltage at the point of common coupling is rarely a pure sinusoid. It has become necessary to identify accurately which load(s) is injecting the excessively high harmonic currents. Simply measuring the harmonic currents at each individual load is not sufficiently accurate since these harmonic currents may be caused by not only the nonlinear load, but also by a non-sinusoidal PCC …

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A Biologically Plausible System Approach For Noise Robust Vowel Recognition, Ismail Uysal, Harsha Sathyendra, John G. Harris Dec 2006

A Biologically Plausible System Approach For Noise Robust Vowel Recognition, Ismail Uysal, Harsha Sathyendra, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

Present day commercial automatic speech recognition (ASR) systems still pale in comparison to the human ability to recognize speech. For decades, people tried to mimic biology for machine recognition tasks and ASR is no exception. Widely used and accepted Mel Frequency Cepstral Coefficients, for example, try to develop better filter banks by looking at the distribution of the hair cells along the basilar membrane. However, all these approaches stem only from topological and anatomical considerations. This research proposes to take this biological inspiration one step further by imitating some of the dynamical computation of our auditory system via describing a …

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Development And Implementation Of Optimized Energy-Delay Sub-Network Routing Protocol For Wireless Sensor Networks, James W. Fonda, Maciej Zawodniok, S. Jagannathan, Steve E. Watkins Dec 2006

Development And Implementation Of Optimized Energy-Delay Sub-Network Routing Protocol For Wireless Sensor Networks, James W. Fonda, Maciej Zawodniok, S. Jagannathan, Steve E. Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

The development and implementation of the optimized energy-delay sub-network routing (OEDSR) protocol for wireless sensor networks (WSN) is presented. This on demand routing protocol minimizes a novel link cost factor which is defined using available energy, end-to-end (E2E) delay and distance from a node to the base station (BS), along with clustering, to effectively route information to the BS. Initially, the nodes are either in idle or sleep mode, but once an event is detected, the nodes near the event become active and start forming sub-networks. Formation of the inactive network into a sub-network saves energy because only a portion …

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Inter-Turn Fault Diagnosis In Induction Motors Using The Pendulous Oscillation Phenomenon, Behrooz Mirafzal, Richard J. Povinelli, Nabeel Demerdash Dec 2006

Inter-Turn Fault Diagnosis In Induction Motors Using The Pendulous Oscillation Phenomenon, Behrooz Mirafzal, Richard J. Povinelli, Nabeel Demerdash

Electrical and Computer Engineering Faculty Research and Publications

A robust interturn fault diagnostic approach based on the concept of magnetic field pendulous oscillation, which occurs in induction motors under faulty conditions, is introduced in this paper. This approach enables one to distinguish and classify an unbalanced voltage power supply and machine manufacturing/construction imperfections from an interturn fault. The experimental results for the two case studies of a set of 5-hp and 2-hp induction motors verify the validity of the proposed approach. Moreover, it can be concluded from the experimental results that if the circulating current level in the shorted loop increases beyond the phase current level, an interturn …

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Robust Estimation Of Mahalanobis Distance In Hyperspectral Images, Eduardo C. Meidunas Dec 2006

Robust Estimation Of Mahalanobis Distance In Hyperspectral Images, Eduardo C. Meidunas

Theses and Dissertations

This dissertation develops new estimation methods that fit Johnson distributions and generalized Pareto distributions to hyperspectral Mahalanobis distances. The Johnson distribution fit is optimized using a new method which monitors the second derivative behavior of exceedance probability to mitigate potential outlier effects. This univariate distribution is then used to derive an elliptically contoured multivariate density model for the pixel data. The generalized Pareto distribution models are optimized by a new two-pass method that estimates the tail-index parameter. This method minimizes the mean squared fitting error by correcting parameter values using data distance information from an initial pass. A unique method …

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A Fuzzy Logic Controller For Autonomous Wheeled Vehicles, Mohamed Trabia, Linda Z. Shi, Neil Eugene Hodge Dec 2006

A Fuzzy Logic Controller For Autonomous Wheeled Vehicles, Mohamed Trabia, Linda Z. Shi, Neil Eugene Hodge

Mechanical Engineering Faculty Research

Autonomous vehicles have potential applications in many fields, such as replacing humans in hazardous environments, conducting military missions, and performing routine tasks for industry. Driving ground vehicles is an area where human performance has proven to be reliable. Drivers typically respond quickly to sudden changes in their environment. While other control techniques may be used to control a vehicle, fuzzy logic has certain advantages in this area; one of them is its ability to incorporate human knowledge and experience, via language, into relationships among the given quantities. Fuzzy logic controllers for autonomous vehicles have been successfully applied to address various …

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2006 Fall Engr333 Project Posters, 2006 Fall Engr333 Nov 2006

2006 Fall Engr333 Project Posters, 2006 Fall Engr333

ENGR 333

To demonstrate Calvin’s interest in alternative energy by developing a short-term plan to implement a demonstration wind turbine and a long-term plan to determine the feasibility of a larger turbine for the future.

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Synergistic Functions Of Trimethl Phosphate And Vinylene Carbonate As Additives For The Li-Ion Batteries, Zhi-Yuan Tang, Yan-Bing He, Quan-Sheng Song, Yu-Hong Chen, Yuan-Gang Liu, Qiang Liu Nov 2006

Synergistic Functions Of Trimethl Phosphate And Vinylene Carbonate As Additives For The Li-Ion Batteries, Zhi-Yuan Tang, Yan-Bing He, Quan-Sheng Song, Yu-Hong Chen, Yuan-Gang Liu, Qiang Liu

Journal of Electrochemistry

The cooperative effects of trimethl phosphate and vinylene carbonate as additives for Li-ion batteries are investigated by using the cyclic voltammetry,electrochemical impedance spectroscopy and scanning electronic micro-photographs.The results show that the combination application of TMP and VC as additives for Li-ion batteries not only enhances safety of the batteries,but also improves their cycling performance.The reason may be ascribed to firstly VC being reduced and the reduction product polymerized to form excellent solid electrolyte interface(SEI) layer on the surface of graphite electrode during the first charge and discharge process,which prevents effectively the decomposition of TMP on the surface of the graphite …

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Facilitated Effect Of Ag To Oxygen Transportation In Pem Fuel Cell Air Cathodes, Hong-Feng Xu, Jian-Hua Dong, Xiang-Li Hou Nov 2006

Facilitated Effect Of Ag To Oxygen Transportation In Pem Fuel Cell Air Cathodes, Hong-Feng Xu, Jian-Hua Dong, Xiang-Li Hou

Journal of Electrochemistry

Silver(Ag) was deposited in the pores of Nafion membrane by ion exchange and succedent hydrogen reduction;the structures of Nafion-Ag membrane were measured by TEM and XRD,the diffusion coefficients of oxygen in Nafion-Ag was determined by electrochemical limited current method.The results showed that after deposited silver,the pores in the Nafion were enlarged by silver grains;the oxygen diffusion coefficient was increased about four times.By introducing silver in the thin Nafion film around the cathode catalyst,the performance of PEM fuel cell have a evident increasing in high current density, which shows the facilitated effects of silver to oxygen transportation in PEM fuel cell.

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Electrochemical Behavior Of Buprofezin On Glass-Carbon Electrode, Qi Wang, Chang-Guo Chen Nov 2006

Electrochemical Behavior Of Buprofezin On Glass-Carbon Electrode, Qi Wang, Chang-Guo Chen

Journal of Electrochemistry

Electrochemical behavior of Bup has been investigated by means of cyclic voltammetry,linear sweep voltammetry,differential pulse voltammetry and square wave voltammetry.The results indicate that the electrochemical behavior of Bup on the surface of glassy carbon electrode is corresponding to a irreversible two-protons and two-electrons process with absrption.The square wave voltammetry for determination of Bup in actual samples has been established.

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Synthesis Of Monolithic Carbon/Nickel Oxide Composite Electrode Material And Cyclic Voltammetry Characteristics, Tian-Ying Guo, Jing-Wei Zhu, Mou-Dao Song, Bang-Hua Zhang Nov 2006

Synthesis Of Monolithic Carbon/Nickel Oxide Composite Electrode Material And Cyclic Voltammetry Characteristics, Tian-Ying Guo, Jing-Wei Zhu, Mou-Dao Song, Bang-Hua Zhang

Journal of Electrochemistry

Monolithic carbon/nickel oxide composite materials were synthesized by carbonization of phenol formaldehyde gels that were ion-exchanged with Ni2+.Atomic absorption spectroscopy and powder X-ray diffraction technique were used to characterize the chemical composition and physical structure of the materials.The nickel dope amount for this method can reach 5.9 %(by mass).Subsequent cyclic voltammetry experiments indicate that the materials exhibit best capacitive performance at the nickel content of 4.4 %.

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Performance And Characterization Of A Large Format Solid State Imager, Jacob A. Mendez Nov 2006

Performance And Characterization Of A Large Format Solid State Imager, Jacob A. Mendez

Electrical and Computer Engineering ETDs

The purpose of this thesis is to validate the specifications of the CCD 486 as specified by Fairchild Imaging, the manufacturer of the CCD and Spectral Instruments, the manufacturer of the camera control electronics and supporting hardware. Specifications have been provided by both companies and are shown in Appendix A. This study is necessary because of the nature of the experiments to be analyzed using the CCD 486. In addition, the thesis will propose new testing methods for electronically shuttered CCD imagers that are not well understood.

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Novel Electrochemical Method For Synthesis Of Nanostructured Materials Of Noble Metals Based On Poly(N-Vinylpyrrolidone) (Pvp), Wei Pan, Xiao-Kai Zhang, Ming-Hu Huang, Shao-Xin Huang, Xing-Li Feng, Hou-Yi Ma Nov 2006

Novel Electrochemical Method For Synthesis Of Nanostructured Materials Of Noble Metals Based On Poly(N-Vinylpyrrolidone) (Pvp), Wei Pan, Xiao-Kai Zhang, Ming-Hu Huang, Shao-Xin Huang, Xing-Li Feng, Hou-Yi Ma

Journal of Electrochemistry

Gold nanocrystals with controllable size were synthesized through a simple electroreduction method using poly(N-vinylpyrrolidone)(PVP) of different polymerization degree as both stabilizer and shape-controller for gold nanoclusters.Individual gold nanoparticles spontaneously assembled into the wire-and ring-shaped nanoparticle aggregates depending on the PVP's dynamic stretching and curling,and precursor nanoparticles grew into flat,single-crystalline nanoprisms with thickness of dozens of nanometers based on the oriented aggregation between particles.Besides,core-shell Au/Ag nanoparticles were conveniently synthesized through two-step electroreduction of noble metal ions in the presence of PVPK30.The electrochemical synthetic method based on PVP provides a new path for preparation of noble metal nanostructured materials with different shape …

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Study Of The Electrooxidation Of Glycerol On Oxide And Pd/C Composite Catalysts, Zhi-Yuan Yan, Chang-Wei Xu, Pei-Kang Shen Nov 2006

Study Of The Electrooxidation Of Glycerol On Oxide And Pd/C Composite Catalysts, Zhi-Yuan Yan, Chang-Wei Xu, Pei-Kang Shen

Journal of Electrochemistry

Oxide and Pd on carbon composite catalysts have been prepared by intermittent microwave heating(IMH) method.The performance of the catalysts for glycerol oxidation in alkaline solution is studied by electrochemical techniques.It is shown that the Pd/C catalyst is active for glycerol electrooxidation.However,the oxide-Pd/C catalysts are even better in terms of the onset potential that is more negative and peak current density.The ratio of oxide to Pd is optimized according to the electrochemical measurement.The results reveal that the addition of oxide into the Pd/C induces the synergistic effect for glycerol electrooxidation.

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Electrochemical Properties Of The Modified Carbon Nanotubes, Chun-An Ma Nov 2006

Electrochemical Properties Of The Modified Carbon Nanotubes, Chun-An Ma

Journal of Electrochemistry

Powder micro-electrodes were prepared from raw carbon nanotubes and carbon nanotubes modified by carboxyl.The electro-reduction properties of both the raw and open-ended carbon nanotubes in p-Nitrophenol solution were investigated.The FTIR spectrum result indicated that the functional groups are successfully fixed on the surface of the carbon nanotubes after nitric acid treatment.The cyclic voltammetry results show that the electrochemical activity of carboxyl-modified carbon nanotubes was improved.The mechanism of electro-(reduction) for the carbon nanotubes after acid treatment was discussed.

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Reaction Mechanism Of V(Ⅳ)/V(Ⅴ) Redox Couple At Graphite Felt Composite Electrode Bonded With Conductive Carbon Plastic, Xiao-Gang Li, Ke-Long Huang, Su-Qin Liu, Ning Tan, Li-Quan Chen Nov 2006

Reaction Mechanism Of V(Ⅳ)/V(Ⅴ) Redox Couple At Graphite Felt Composite Electrode Bonded With Conductive Carbon Plastic, Xiao-Gang Li, Ke-Long Huang, Su-Qin Liu, Ning Tan, Li-Quan Chen

Journal of Electrochemistry

The rate-determining step of V(Ⅳ) /V(Ⅴ) redoxreaction was investigated at graphite felt(GF)composite electrode by various techniques: cyclic voltammetry,polarization curve and impedance spectroscopy.Cyclic voltammetry analysis indicated that V(Ⅳ) /V(Ⅴ) redox reaction at GF electrode is quasi reversible.Acertain chemical reaction step is suspected to follow the electron transfer step of this reaction.The Tafel slopevalue(0.124) obtained from the polarization curve agrees well with theoretical value(0.12),which supposingthe electron transfer step was the rate-determining step.Impedance Spectroscopies at various potentials werestudied and simulated by equivalentcircuits.The impedance value of the electron transfer step modified is greatlyhigher than the others,which shows that the electron transfer step is the …

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The Synthesis, Structure And Electrochemical Performances Of Lithium Iron Phosphate, Hui Xie, Zhen-Tao Zhou Nov 2006

The Synthesis, Structure And Electrochemical Performances Of Lithium Iron Phosphate, Hui Xie, Zhen-Tao Zhou

Journal of Electrochemistry

The lithium iron phosphate cathode materials were synthesized by solid-state reaction combined high-rate ball milling under the temperature ranging from 400 ℃ to 700 ℃.The crystalline structure, morphology of particles, and electrochemical performance of the sample were investigated by X-ray diffraction, scanning electron microscopy and charge-discharge test. The results showed that the sintering temperature had great influences on the crystal structure, morphology and electrochemical performances of LiFePO4. The sample synthesized under 600℃ showed the best charge-discharge performances with the first specific discharge capacity of(128.8) mAh/g and the 15th specific discharge capacity of 129.1 mAh/g at 0.1C rate, …

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