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2005

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Articles 1711 - 1740 of 3074

Full-Text Articles in Engineering

Performance Based Service Acquisition: A Quantitative Evaluation Of Implementation Goals And Performance In The United States Air Force, Dylan D. Pope Mar 2005

Performance Based Service Acquisition: A Quantitative Evaluation Of Implementation Goals And Performance In The United States Air Force, Dylan D. Pope

Theses and Dissertations

In an attempt to maximize cost savings in the rapidly growing services sector, the DoD established a Performance Based Service Acquisition (PBSA) strategy that focuses on evaluating contractor performance based on their ability to meet desired outcomes rather than the means to which the outcomes are obtained. In April 2000, Dr. Gansler, then Under Secretary of Defense for Acquisition, Technology and Logistics, mandated that 50 percent of all eligible service acquisitions be awarded using PBSA methods by FY 2005. Since then very little research has been focused on USAF implementation of PBSA and the progress and attainment of the PBSA …

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Enabling Intrusion Detection In Ipsec Protected Ipv6 Networks Through Secret-Key Sharing, Patrick J. Sweeney Mar 2005

Enabling Intrusion Detection In Ipsec Protected Ipv6 Networks Through Secret-Key Sharing, Patrick J. Sweeney

Theses and Dissertations

As the Internet Protocol version 6 (IPv6) implementation becomes more widespread, the IP Security (IPSec) features embedded into the next-generation protocol will become more accessible than ever. Though the network-layer encryption provided by IPSec is a boon to data security, its use renders standard network intrusion detection systems (NIDS) useless. The problem of performing intrusion detection on encrypted traffic has been addressed by differing means with each technique requiring one or more static secret keys to be shared with the NIDS beforehand. The problem with this approach is static keying is much less secure than dynamic key generation through the …

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Performance Of A Spectrally Encoded Multi-Carrier Phase Shift Keying Communications System In A Frequency-Selective, Slowly-Fading Multipath Channel, Charles M. Gaona Mar 2005

Performance Of A Spectrally Encoded Multi-Carrier Phase Shift Keying Communications System In A Frequency-Selective, Slowly-Fading Multipath Channel, Charles M. Gaona

Theses and Dissertations

This research examines the performance of a spectrally encoded, multi-carrier, phase shift keying communications system in a frequency-selective, slowly-fading multipath channel. The specific communications system modeled is the transform domain communication system (TDCS) originally researched as an interference avoidance technique. Previous TDCS research assumed an additive white Gaussian noise channel, which is not representative of a realistic environment. This thesis presents overviews of previous TDCS research, the multipath fading channel, and the RAKE receiver. Analysis and Matlab simulations compare the performance of spectrally encoded and un-encoded signals through a multipath fading channel using an L-diversity TDCS RAKE receiver. Encoded signals …

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Head Tracking For 3d Audio Using A Gps-Aided Mems Imu, Jacque M. Joffrion Mar 2005

Head Tracking For 3d Audio Using A Gps-Aided Mems Imu, Jacque M. Joffrion

Theses and Dissertations

Audio systems have been developed which use stereo headphones to project sound in three dimensions. When using these 3D audio systems, audio cues sound like they are originating from a particular direction. There is a desire to apply 3D audio to general aviation applications, such as projecting control tower transmissions in the direction of the tower or providing an audio orientation cue for VFR pilots who find themselves in emergency zero-visibility conditions. 3D audio systems, however, require real-time knowledge of the pilot's head orientation in order to be effective. This research describes the development and testing of a low-cost head …

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Finite Difference Time Domain (Fdtd) Analysis Of A Leaky Traveling Wave Microstrip Antenna, Gregory M. Zelinski Mar 2005

Finite Difference Time Domain (Fdtd) Analysis Of A Leaky Traveling Wave Microstrip Antenna, Gregory M. Zelinski

Theses and Dissertations

This thesis provides the groundwork that will enable the development of a lightweight, inexpensive, aerodynamic, and broadband antenna. Whether for radar or communication, an antenna with these properties would be a force multiplier for the smaller, limited payload air vehicles the United States Air Force will pursue in the coming years. Several microstrip antennas using the first higher order mode were simulated with the Finite-Difference Time-Domain (FDTD) method. The propagation constant of each antenna was extracted from the resulting field distribution for comparison with a transverse resonance approximation, measured far-field patterns, and other simulated antennas. Variations of the geometry were …

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Doppler Aliasing Reduction In Wide-Angle Synthetic Aperture Radar Using A Linear Frequency Modulated Random Stepped-Frequency Waveform, Jason R. Mcmahon Mar 2005

Doppler Aliasing Reduction In Wide-Angle Synthetic Aperture Radar Using A Linear Frequency Modulated Random Stepped-Frequency Waveform, Jason R. Mcmahon

Theses and Dissertations

This research examines the theory, application, and results of using Random Stepped-Frequency (RSF) waveforms to mitigate Doppler aliasing in a wide-angle Synthetic Aperture Radar (SAR) imaging scenario. Severe Doppler aliasing typically occurs in this scenario since range extent requirements force the pulse repetition frequency to a value violating the lower bound for Doppler aliasing. Building on previous research, this work expands upon RSF waveform analysis using a Linear Frequency Modulated RSF (LFM-RSF) waveform. The RSF waveform suppresses Doppler aliasing by positioning nulls at the aliased scatterer location. Applying LFM with RSF processing theoretically provides greater frequency coverage and aliased scatterer …

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Study Of Behavior Of Digital Modulations For Beam Steerable Reflectarray Antennas, Fuqin Xiong, Robert R. Romanofsky Mar 2005

Study Of Behavior Of Digital Modulations For Beam Steerable Reflectarray Antennas, Fuqin Xiong, Robert R. Romanofsky

Electrical and Computer Engineering Faculty Publications

This paper investigates the bit error rate (BER) performance of digital modulations in a system with a scanning reflectarray antenna. A reflectarray causes intersymbol interference (ISI) in a digitally modulated signal, its phase shifters' phase errors cause signal distortion, and its phase shifters' phase transient causes beam pattern degradation during direction switching. In this paper, composite signal models of the reflectarray are established for both static and transient states. Due to different feed-to-element distances and the element-to-observation distances, different delays exist in signal components. These delays cause ISI whose effect is analyzed and evaluated. Effects of phase shifters' phase errors …

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A Wavelet-Based Multiresolution Pid Controller, Shahid Parvez, Zhiqiang Gao Mar 2005

A Wavelet-Based Multiresolution Pid Controller, Shahid Parvez, Zhiqiang Gao

Electrical and Computer Engineering Faculty Publications

A novel controller based on multiresolution decomposition using wavelets is presented. The controller is similar to a proportional-integral-derivative (PID) controller in principle and application. The output from a motion control system represents the cumulative effect of uncertainties such as measurement noise, frictional variation, and external torque disturbances, which manifest at different scales. The wavelet is used to decompose the error signal into signals at different scales. These signals are then used to compensate for the uncertainties in the plant. This approach provides greater expanse over the degree of control applied to the system. Through hardware and simulation results on motion …

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Effect Of Training Datasets On Support Vector Machine Prediction Of Protein-Protein Interactions, Siaw Ling Lo, Cong Zhong Cai, Maxey Chung, Yu Zong Chen Mar 2005

Effect Of Training Datasets On Support Vector Machine Prediction Of Protein-Protein Interactions, Siaw Ling Lo, Cong Zhong Cai, Maxey Chung, Yu Zong Chen

Research Collection School Of Computing and Information Systems

Knowledge of protein-protein interaction is useful for elucidating protein function via the concept of 'guilt-by-association'. A statistical learning method, Support Vector Machine (SVM), has recently been explored for the prediction of protein-protein interactions using artificial shuffled sequences as hypothetical noninteracting proteins and it has shown promising results (Bock, J. R., Gough, D. A., Bioinformatics 2001, 17, 455-460). It remains unclear however, how the prediction accuracy is affected if real protein sequences are used to represent noninteracting proteins. In this work, this effect is assessed by comparison of the results derived from the use of real protein sequences with that derived …

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Multi-Criteria Decision Analysis For The Optimal Management Of Nitrate Contamination Of Aquifers, Mohammad N. Almasri, Jagath J. Kaluarachchi Mar 2005

Multi-Criteria Decision Analysis For The Optimal Management Of Nitrate Contamination Of Aquifers, Mohammad N. Almasri, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

We present an integrated methodology for the optimal management of nitrate contamination of ground water combining environmental assessment and economic cost evaluation through multi-criteria decision analysis. The proposed methodology incorporates an integrated physical modeling framework accounting for on-ground nitrogen loading and losses, soil nitrogen dynamics, and fate and transport of nitrate in ground water to compute the sustainable on-ground nitrogen loading such that the maximum contaminant level is not violated. A number of protection alternatives to stipulate the predicted sustainable on-ground nitrogen loading are evaluated using the decision analysis that employs the importance order of criteria approach for ranking and …

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Assessment Of Aquifer Vulnerability Due To Heavy Metals Using Ordinal Logistic Regression Analysis, N. K. Twarakavi, Jagath J. Kaluarachchi Mar 2005

Assessment Of Aquifer Vulnerability Due To Heavy Metals Using Ordinal Logistic Regression Analysis, N. K. Twarakavi, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

A methodology using ordinal logistic regression is proposed to predict the probability of occurrence of heavy metals in ground water. The predicted probabilities are defined with reference to the background concentration and the maximum contaminant level. The model is able to predict the occurrence due to different influencing variables such as the land use, soil hydrologic group (SHG), and surface elevation. The methodology was applied to the Sumas-Blaine Aquifer located in Washington State to predict the occurrence of five heavy metals. The influencing variables considered were (1) SHG; (2) land use; (3) elevation; (4) clay content; (5) hydraulic conductivity; and …

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Sea Ice Mapping Method For Seawinds, David G. Long, Hyrum S. Anderson Mar 2005

Sea Ice Mapping Method For Seawinds, David G. Long, Hyrum S. Anderson

Faculty Publications

A sea ice mapping algorithm for SeaWinds is developed that incorporates statistical and spatial a priori information in a modified maximum a posteriori (MAP) framework. Spatial a priori data are incorporated in the loss terms of a Bayes risk formulation. Conditional distributions and priors for sea ice and ocean statistics are represented as empirical histograms that are forced to conform to a set of expected histograms via principal component filtering. Tuning parameters for the algorithm allow adjustments in the algorithm's performance. Results of the algorithm exhibit high correlation with the Remund-Long sea ice mapping algorithm for SeaWinds and the Special …

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Numerical Simulation Of Live Chaparral Fire Behavior Using Firetec, Lulu Sun, Xiangyang Zhou, Shankar Mahalingam, Jesse Canfield, Rodman Linn Mar 2005

Numerical Simulation Of Live Chaparral Fire Behavior Using Firetec, Lulu Sun, Xiangyang Zhou, Shankar Mahalingam, Jesse Canfield, Rodman Linn

Publications

Fire spread through chaparral fuels is a significant feature of wildland fire in southern California. In order to study the detailed physical processes involved during fire spread, FIRETEC, a coupled atmosphere/wildfire behavior model was refined to examine chaparral fire behavior. FIRETEC combines a sophisticated fine-scale model to simulate a three- dimensional wildfire, moving over a terrain-following finite volume grid, with the motions of the local atmosphere. It accounts for the microscopic details of a fire with macroscopic resolution by dividing quantities into mean and fluctuating parts and the resulting transport equations are solved by using a finite difference method. In …

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An In Vitro Comparison Of The Rake Angles Between K3 And Profile Endodontic File Systems, David Y. Chow, Sheila E. Stover, James Bahcall, Andris Jaunberzins, Jeffrey M. Toth Mar 2005

An In Vitro Comparison Of The Rake Angles Between K3 And Profile Endodontic File Systems, David Y. Chow, Sheila E. Stover, James Bahcall, Andris Jaunberzins, Jeffrey M. Toth

Biomedical Engineering Faculty Research and Publications

The purpose of this study was to compare rake angles of the ProFile and K3 file systems. Twenty-five 40/0.06 taper files were obtained for each system. Five files from the same manufacturer were placed perpendicularly into a vial of Epoxicure Resin and left to set for 24 h. The set-ups were removed from the vials and each were sectioned 5 mm from the tip of the files and polished. A photomicrograph was taken of each file with 100× magnification. Five sets of ProFile and five sets of K3 files were processed in this manner. Images were captured digitally, and rake …

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Probabilistic Modeling Of One Dimensional Water Movement And Leaching From Highway Embankments Containing Secondary Materials, Defne S. Apul, Kevin H. Gardner, T. Taylor Eighmy, Ernst Linder, Tara Frizzell, Ruth Roberson Feb 2005

Probabilistic Modeling Of One Dimensional Water Movement And Leaching From Highway Embankments Containing Secondary Materials, Defne S. Apul, Kevin H. Gardner, T. Taylor Eighmy, Ernst Linder, Tara Frizzell, Ruth Roberson

Civil & Environmental Engineering

Predictive methods for contaminant release from virgin and secondary road construction materials are important for evaluating potential long-term soil and groundwater contamination from highways. The objective of this research was to describe the field hydrology in a highway embankment and to investigate leaching under unsaturated conditions by use of a contaminant fate and transport model. The HYDRUS2D code was used to solve the Richards equation and the advection–dispersion equation with retardation. Water flow in a Minnesota highway embankment was successfully modeled in one dimension for several rain events after Bayesian calibration of the hydraulic parameters against water content data at …

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Fabrication And Studies Of A Novel Ag/Agcl Reference Electrode In High Temperature Molten Chloride Salts, Pei Gao, Xian-Bo Jin, Di-Hua Wang, Xiao-Hong Hu, Zheng Chen Feb 2005

Fabrication And Studies Of A Novel Ag/Agcl Reference Electrode In High Temperature Molten Chloride Salts, Pei Gao, Xian-Bo Jin, Di-Hua Wang, Xiao-Hong Hu, Zheng Chen

Journal of Electrochemistry

A new method for the easy fabrication of a stable and long life silver/silver chloride reference electrode in molten chloride salts is described in this paper. The method is based on the fact that simply placing the silica glass in molten NaCl or its vapour in the presence of oxygen resulted in satisfactory conductivity for sodium ion and possibly calcium ion in the material.The performance of such made electrode has been investigated in a few typical chloride systems at temperatures ranging from 400 to 900℃. Due to the wholly sealed construction, the reference electrode is stable, temperature-reversible, contamination free to …

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Anodic Polarization Behaviors Of Carbon Steel In Bicarbonate Solution, Jing-Mao Zhao, Yu Zuo Feb 2005

Anodic Polarization Behaviors Of Carbon Steel In Bicarbonate Solution, Jing-Mao Zhao, Yu Zuo

Journal of Electrochemistry

The anodic polarization curves of mild steel were measured in sodium bicarbonate solution of various concentrations, and the surface products were analyzed by XPS. Two anodic current peaks and two passive zones are observed in all the curves. When HCO3- ions concentration is below 0.1mol/L, the two peaks are so close that the first passive zone is difficult to be observed. When HCO3- ions concentration is above 0.1 mol/L, the first peak appears clear, while the second becomes smaller. The XPS results indicate that the out layer of film formed at a higher potential is mainly …

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Preparation And Characterization Of Lini0.85Co0.10(Timg)0.025O2 As Cathode Materials For Lithium-Ion Batteries, Xian-Jun Zhu, Hong-Hao Chen, Hui Zhan, Dai-Ling Yang, Yun-Hong Zhou Feb 2005

Preparation And Characterization Of Lini0.85Co0.10(Timg)0.025O2 As Cathode Materials For Lithium-Ion Batteries, Xian-Jun Zhu, Hong-Hao Chen, Hui Zhan, Dai-Ling Yang, Yun-Hong Zhou

Journal of Electrochemistry

Cathode material of LiNi0.85Co0.10(TiMg)0.025O2 were prepared by solid state reaction at 725℃ for 24 h from LiOH·H2O, Ni2O3, Co2O3, TiO2 and Mg(OH)2 under flowing oxygen, and were characterized by TG-DTA, XRD, SEM and electrochemical tests. Effort to simultaneously doped LiNiO2 with Co-Ti-Mg has been tried to improve the cathode performance. The results show that co-doping definitely has a large beneficial effect in increasing the capacity (182.7mAh/g of the first discharge capacity for  LiNi0.85Co0.10(TiMg)0.025O2 …

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Corrosion Resistance For Tio2 Thin Films Coated 316l Stainless Steel In The Nacl Solution, Guang-Xia Shen, Yi-Cong Chen, Chang-Jian Lin Feb 2005

Corrosion Resistance For Tio2 Thin Films Coated 316l Stainless Steel In The Nacl Solution, Guang-Xia Shen, Yi-Cong Chen, Chang-Jian Lin

Journal of Electrochemistry

The nano-TiO2 thin films have been deposited on the 316L stainless steel by sol-gel and the dip-coating methods. Hydrothermal post-treatment leads to crack-free coatings. Meanwhile, the surface structure and properties are optimized. Surface morphology, structure and properties are characterized by XRD, and SEM technologies. The results have shown that the surface of coatings is porous, uniform and orderly, the particle diameters are in the range of 15~18 nm and the pores are about 4~8 nm and TiO2 is anatase. The results of electrochemical measurements show that in the NaCl solution with pH ≥ 2 and concentration below 1mol/L, …

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Calcium Zincate Prepared By Ball Mill Method, Sheng-Xian Li, Shuan-Bao Tian, Shao-Shan Zhu Feb 2005

Calcium Zincate Prepared By Ball Mill Method, Sheng-Xian Li, Shuan-Bao Tian, Shao-Shan Zhu

Journal of Electrochemistry

Calcium zincate was prepared by ball milling method and the factors that influence its synthesis were investigated. The composition of the compound was Ca(OH)2·2Zn(OH)2·2H2O, which was verified by XRD and TG-DTA methods. The results of powder microelectrode and in simulated batteries showed that the material had excellent cyclic performance.

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Influence Of Rare Earth Oxide On The Performance Of Secondary Zinc Electrodes, Xian-Ling Meng, Hua-Bin Yang, Jun-Hong Wang, Zuo-Xiang Zhou Feb 2005

Influence Of Rare Earth Oxide On The Performance Of Secondary Zinc Electrodes, Xian-Ling Meng, Hua-Bin Yang, Jun-Hong Wang, Zuo-Xiang Zhou

Journal of Electrochemistry

Influence of La(OH)3 or Ce(OH)3 in secondary zinc electrode was investigated by the cyclic voltammetry, potentiodynamic polarizationand potentiostatic polarization tests and influence of La2O3 or CeO2 in the charge/discharge performance of Zn/Ni battery was studied by galvanostatic charge/discharge experiment. The results showed that the film of rare earth hydroxide prevented the zincate species from transferring toward solution, enhanced hydrogen overpotential and decreased thecorrosion current density (icorr), and therefore inhibited zinc corrosion. The potentiostatic polarization results at100mV overpotential showed that La(OH)3 or Ce(OH)3 oated on the zinc electrode effectively suppressed the …

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The Fabrication And Electrochemical Studies On Carbon Nanotube Array Electrodes, Quan-Yong Gao, Jing Zhang, Yong Yang Feb 2005

The Fabrication And Electrochemical Studies On Carbon Nanotube Array Electrodes, Quan-Yong Gao, Jing Zhang, Yong Yang

Journal of Electrochemistry

An improved technique for fabrication of carbon nanotube array electrodes has been proposed in this work. Firstly, carbon nanotubes (CNs) array electrodes were prepared by combsination of Chemical Vapor Decomposition (CVD) method and sputtering techniques in anodized aluminum oxide (AAO) membrane. The CNs/AAO was immersed into HF solution to remove the barrier layer. Controlling the immersing time, the CNs array electrodes with different length contacted with electrolyte can be prepared. The morphology of CNs array electrodes was observed by SEM. The electrochemical properties of CNs array electrodes were investigated by cyclic voltammetry and electrochemical impedance spectroscopy. Cyclic voltammetric curves of …

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Studies On Polymer Light-Emitting Electrochemical Cells ——Introduction Of The Studies On The Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids (Ⅱ), Yong-Fang Li Feb 2005

Studies On Polymer Light-Emitting Electrochemical Cells ——Introduction Of The Studies On The Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids (Ⅱ), Yong-Fang Li

Journal of Electrochemistry

Polymer light-emitting electrochemical cell (LEC) is composed of a conjugated polymer(CP)/polymer electrolyte blend film sandwiched between an ITO anode and an Al cathode. When a bias voltage greater than Eg/e (where Eg is the energy gap of the CP, e is the electron charge) is applied on the two electrodes, the CP in the polymer blend film at the anode side will be oxidized (to form a p-doped region), and that at the cathode side will be reduced (to form a n-doped region), then a p-i-n junction will be produced. Light-emission occurs in the intrinsic region between the p- and …

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Corrosion Behavior Of Mg2-XLaXNi And Mg2-XCeXNi Hydrogen Storage Alloy, Hai-Chang Zhang, Hua-Bin Yang, Jun-Hong Wang, Zuo-Xiang Zhou Feb 2005

Corrosion Behavior Of Mg2-XLaXNi And Mg2-XCeXNi Hydrogen Storage Alloy, Hai-Chang Zhang, Hua-Bin Yang, Jun-Hong Wang, Zuo-Xiang Zhou

Journal of Electrochemistry

The corrosion behavior of Mg-base hydrogen storage alloys has been investigated by potentiodynamic polarization and EIS. The results showed that the corrosion current density (icorr) and the electrochemical polarized resistance of Mg2-xCexNi alloys decreased with x increase, while icorr of Mg2-xLaxNi alloys increased and the electrochemical polarized resistance of Mg2-xLaxNi alloys increased first, then decreased with x increase. SEM results showed that the surface of Mg1.85Ce0.15Ni alloy was relatively even while the surface of Mg2-xLaxNi alloy had …

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A Study Of Metal Borides As High Capacity Anode Materials For Aqueous Primary Batteries, Ya-Dong Wang, Xin-Ping Ai, Han-Xi Yang Feb 2005

A Study Of Metal Borides As High Capacity Anode Materials For Aqueous Primary Batteries, Ya-Dong Wang, Xin-Ping Ai, Han-Xi Yang

Journal of Electrochemistry

The transition metal borides VB2 and TiB2 were tested as high capacity anode materials and their electrochemical behaviors were studied by cyclic voltammetry and discharge measurements. The experimental results indicated that transition metal borides VB2 and TiB2 electrodes can deliver exceptionally high discharge capacity of over 3100 mAh/g and 1 600 mAh/g respectively, corresponding to 11- and 6-electron oxidation reaction, although their parent elements V, Ti and boron, are almost completely electrochemically inert. The different electrochemical activitis were probably due to the electrochemical activation of boron, which clamp the potential to passivation for Ti and activity …

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Electrochemical Performance Of Gel Polymer Electrolyte Prepared By Thermal Initiating Polymerization Of Acrylates, Jin-Dan Piao, Li-Xia Yuan, Xin-Ping Ai, Han-Xi Yang, Yu-Liang Cao Feb 2005

Electrochemical Performance Of Gel Polymer Electrolyte Prepared By Thermal Initiating Polymerization Of Acrylates, Jin-Dan Piao, Li-Xia Yuan, Xin-Ping Ai, Han-Xi Yang, Yu-Liang Cao

Journal of Electrochemistry

A gel polymer electrolyte was prepared by thermal initiating polymerization of the acrylates in the EC/EMC/DMC electrolyte solution at 100℃. The LiCoO2/MCMB polymer cells were assembled and their electrochemical properties were evaluated at various charge-discharge rate and temperatures. The ionic conductivity of the polymer electrolyte containing 85wt.% liquid electrolyte is around 3.2×10-3 S·cm-1  at 20℃ and 5.6×10-4 S·cm-1 at -30℃ respectively. The gel polymer electrolyte has good electrochemical stability up to 4.5V versus Li/Li+.The first charge-discharge efficiency of the polymer cell at 0.2C rate is almost 92.1%. The discharge capacity of the …

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The Electrophoretic Deposition Of Nano Hydroxyapatite Coating On Titanium Surface, Fei Chen, Chang-Jian Lin, Zhou-Cheng Wang Feb 2005

The Electrophoretic Deposition Of Nano Hydroxyapatite Coating On Titanium Surface, Fei Chen, Chang-Jian Lin, Zhou-Cheng Wang

Journal of Electrochemistry

A hydroxyapatite coating with nano-structure on the roughened titanium surface was prepared by electrophoretic deposition process. To decrease sintering temperature the HAp nanoparticles synthesizedby a wet chemical method was used. It is observed that the coating is uniform without cracks. After sintering the nano-strueture of HAp coating remains unchanged. The surface treatment of Ti is applied to form a distribution of small pits and TiO2 thin layer that improve the adhesion of coatingto Ti substrate. It is shown that the bonding strength of coating is as high as 18±2.5MPa. The hardness and Young's modulus are 40.6 and 0.42 GPa, …

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Application Of Carbon Paste Electrode On The Electrogenerative-Leaching Process Of Sulfide Minerals, Shao-Fen Wang, Zheng Fang, Yun-Yan Wang Feb 2005

Application Of Carbon Paste Electrode On The Electrogenerative-Leaching Process Of Sulfide Minerals, Shao-Fen Wang, Zheng Fang, Yun-Yan Wang

Journal of Electrochemistry

The cyclic voltammetry curves of sulfide mineral electrodes or corresponding carbon paste electrodes in NaCl electrolytes have been obtained in this study. The experimental results indicate that acetylene black (revealed) the electro-catalytic propertyin the electrogenerative-leaching process of sulfide minerals. The output currentand potential of carbon paste electrodes were increased to some degrees while the activation energies were lower.

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Preparation And Electrochemical Property Of Aao Nano-Channels Filled With Nio, Chi Gu, Jun-Mei Yan, Yong Yang Feb 2005

Preparation And Electrochemical Property Of Aao Nano-Channels Filled With Nio, Chi Gu, Jun-Mei Yan, Yong Yang

Journal of Electrochemistry

The AAO template with nano-channels was synthesized and filled with transient metal-oxide NiO by sol-gel method, and their electrochemical properties were primarily studied. The results showed that the porous nano-channels were well defined with the diameter about 50nm. The nano-structured NiO was filled into the template's nano-channels successfully. Cyclic voltammetry studies show that the NiO in AAO template has good cycle stability. It was suggested that the AAO-metal-oxides composites could be used as novel anode materials for Lithium ion battery.

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Preparation Of Poly (Bromophenol Blue) Modified Glassy Carbon Electrode And Its Electrocatalytic Activity, Wei Chen, Hong-Bin Luo, Xin-Hua Lin Feb 2005

Preparation Of Poly (Bromophenol Blue) Modified Glassy Carbon Electrode And Its Electrocatalytic Activity, Wei Chen, Hong-Bin Luo, Xin-Hua Lin

Journal of Electrochemistry

A film of poly (bromophenol blue) was formed on a glassy carbon electrode by using cyclic voltammetry. A stable film could be obtained with a potential range from -1.0 V to +1.8 V (vs.Ag/AgCl). The experimental results showed that the poly (bromophenol blue) modified glassy carbon electrode could catalyse the oxidation of ascorbic acid. It decreased the oxidation potential by about 270mV but increased the peak current. Meanwhile, this electrode showed a good linear current response for the ascorbic acid range from 2.5 to 250 (g/mL).

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