Physical Sciences and Mathematics Commons^™

Electrochemical Characteristics Of Silicon-Based Composites, Xin-Xin Xu, Jun Yang

Journal of Electrochemistry

The nano-porous Si/G/C composite was obtained by two-step ball milling with SiO,A1 and graphite,along with HCl acid etching followed by carbon incorparation.This composite demonstrated the reversible capacity of 600 mAh/g with excellent cycling stability,but low initial cycle efficiency is low.A high-temperature treatment after ball-milling of SiO and A1 could promote the complete reduction of SiO.However,the crystalline structure of Al2O3 product changed from γ-phase to α-phase,which it can no longer be etched by HCl.The Si/Al2O3/G/C composite exhibited higher efficiency at the first cycle but relatively poorer cyclability.

Preparation And Performance Of The Thin-Film Libpon Electrolyte, Feng Wu, Ya-Dong Liu, Ren-Jie Chen, Shi Chen

Journal of Electrochemistry

The LiBPON thin-film electrolyte was prepared by magnetron sputtering,and the relationship between the performance and the deposition condition was investigated.As seen in the SEM images,the thin films are dense and uniform without cracks,and according to the XRD patterns they have an amorphous structure.The electrochemical performance of the electrolyte was characterized by electrochemical impedance spectroscopy(EIS).The ionic conductivities of the thin film decreased with the RF power,but increased with the N2 pressure.The an ionic conductivity of 3.5×10-6 S/cm at room temperature was found from the electrochemical measurement.While the deposition rate increased with the RF power,but decreased with the N2 pressure.Nitrogen incorporation can …

Silicon Nanowires As Anode Materials For Lithium Ion Batteries, Yan-Peng Fu, Hui-Xin Chen, Yong Yang

Journal of Electrochemistry

The SiNWs electrodes were fabricated by coating and direct growth methods,respectively.The structure,morphology and electrochemical performance of such materials were characterized by XRD,SEM and charge-discharge tests.The results show that the electrodes prepared by direct growth method had higher capacity,better battery life and also displayed and excellent cyclability at higher currents.During the process of lithiation,the initial crystalline Si transformed to amorphous LixSi,and the average diameter of the SiNWs increased.Despite the large volume changed,the SiNWs remained intact and did not break into smaller particles.

Preparation Of The Protic Ionic Liquid/Pvdf-Hfp Composite Membranes And Its Performance For Dmfc, Rui-Ying Miao, Jian-Ling Li, Yong Fang, Xin-Dong Wang

Journal of Electrochemistry

The protic ionic liquid(PIL) α-methyl pyridinium trifluoroacetate([α-MPyH]Tfa) was synthesized by acid & alkali neutralization.Then PIL/PVDF-HFP composite membranes were prepared by means of phase inversion method using acetone as solvent.The conductivities of the composite membrane increased with the temperature and reached 8×10-3 S/cm,1×10-2 S/cm and 3×10-2 S/cm at room-temperature,30 ℃ and 80 ℃,respectively,by electrochemical impedance method.The properties of the methanol-rejecting of the membranes were measured by chronoamperometry as well.The results indicate that the properties of methanol-resistance of the membranes before and after IL combination were equivalent approximately.

Electrochemical Properties Of Functionalized Carbon Nanotubes And Their Applications In Analysis Of 6-Mercaptopurine, Bao-Yi Lu, Yan-Yan Lai, Hong Li

Journal of Electrochemistry

The electrochemical behaviors and adsorption properties of single-walled carbon nanotubes such as SWNT,SWNT-COOH,and SWNT-OH and multi-walled carbon nanotubes including MWNT,MWNT-COOH,and MWNT-OH modified at a graphite electrode have been investigated by using [Fe(CN)6]3-anion and [Co(phen)3]3+ cation.It was shown that shows good redox reversibility of [Fe(CN)6]3-/4-reactions on the existed carbon nanotubes(CNT) modified electrode.Based on the strong adsorptive property of [Co(phen)3]3+ on the CNT surface,the [Co(phen)3]3+/CNT modified graphite electrode can be obtained by progressive potential sweeping and developed to monitor quantitatively 6-mercaptopurine(6-MP).The adsorption capacity of [Co(phen)3]3+ on the multi-walled carbon nanotubes is higher than that of single-walled carbon nanotubes.For the carbon nanotubes with …

Electrocatalytic Reduction Of Oxygen On Tungsten Carbide Electrode, Chun-An Ma, Yun Huang, Ying-Hong Zhu, Zhao-Yang Chen

Journal of Electrochemistry

Tungsten carbide(WC) catalysts were prepared by gas-solid reaction using ammonium metatungstate as precursors which were pretreated with spray drying sphere miniaturation,carbon monoxide as carrier gas and hydrogen as deoxidizing gas.The WC electrode was fabricated using WC catalyst powders and PTFE as binding agent,and characterized by XRD and SEM.Electrocatalyst behavior of WC for oxygen reduction reaction in the sulphuric acid solution was studied by steady-state voltammetry and cyclic voltammetry.The results show that the WC powders obtained were in spheric particles and the prepared WC electrode had a good electrocatalyst activity to the oxygen reduction reaction.The electrode reaction was controlled by adsorption.The …

Effect Of Irco Intermediate Layer On Electrochemical Property Of Rutisn Anode, Yan Zhao, Gui-Chang Liu, Yong-Lan Liao, Wei-Guang Ji, Shu-Jun Song

Journal of Electrochemistry

The Ti based-RuTiSn anodes with IrCo intermediate layer were prepared by thermal decomposition method.The electrochemical properties of Ti/RuTiSn anodes with different Ir-Co intermediate layers were studied.The surface and elements compositions of the anodes were charactered by scanning electron microscopy(SEM) and electronic probe microanalysis(EPMA).The effects of intermediate layer on the electro-catalytic activity and stability were assessed by chlorine evolution potentials、accelerated lifetime test and cyclic voltammetric curves(CV).It was concluded that the anode,which contained several Ir-Co intermediate layers,could hold not only high electro-catalytic activity but also the increased stability.The enhanced life was up to 480 h.

Spectral Analysis And Synthesis For Radial Sections Of Homogenous Vector Bundles On Certain Noncompath Riemannian Symmetric Spaces., Sanjoy Pusti Dr.

Doctoral Theses

We consider two classical theorems of real analysis which deals with translation invariant subspaces of integrable and smooth functions on R respectively. The first one is a theorem of Norbert Wiener [63] which states that if the Fourier transform of a function f ∈ L 1 (R) has no real zeros then the finite linear combinations of translations f(x − a) of f with complex coefficients form a dense subspace in L 1 (R), equivalently, span{g ∗ f | g ∈ L 1 (R)} is dense in L 1 (R). This theorem is well known as the Wiener-Tauberian Theorem (WTT). …

Image And Video Compression Using Block Truncation Coding And Pattern Fitting For Fast Decoding., Bibhas Chandra Dhara Dr.

Doctoral Theses

In the present era of multimedia, the requirement of image/video storage and transmission for video conferencing, image and video retrieval, video playback, etc. are increasing exponentially. As a result, the need for better compression technology is always in demand. The limited bandwidth of internet also asks for transmission of desired objects only. Progressive image transmission provides such facilities, where transmission is done in steps and the transmission of undesired image can be stopped at an early stage. Modern applications, in addition to high compression ratio, also demand for efficient encoding and decoding processes, so that computational constraint of many real-time …

Diaquabis(5-Fluoro-2-Hydroxybenzoato-Κo1)Zinc(Ii), Diana Rishmawi, Jennifer Kelley, Mark D. Smith, Leroy Peterson, Hans-Conrad Zur Loye

Faculty Publications

The title compound, [Zn(C₇H₄FO₃)₂(H₂O)₂], is a monomeric Zn^II complex. The Zn^II atom, which lies on a twofold rotation axis, is situated in a distorted tetrahedral environment composed of two monodentate carboxlyate O atoms and two water O atoms. O-HO hydrogen bonds link these units, forming sheets that are stacked along the c axis.

The Electrochemical Performance Of Ncf-Sulfur Cathode, Chun-Rong Zhao, Zhong-Bao Yu, Wei-Kun Wang, Yu-Sheng Yang

Journal of Electrochemistry

The electrochemical performance of NCF-sulfur cathode,with different NCF contents,was investigated by constant current discharge,cyclic voltammetry and AC impedance methods.The morphologies of the cathodes were observed using scanning electron microscopy.The results indicate that the cycle life and rate capability of NCF-sulfur cathode increased.Better performance of sulfur cathode was obtained by 3% and 5% NCF conductive addition.When the current density was 0.4 mA/cm2,the 3%NCF-sulfur cathode had an initial capacity of 880 mAh/g and a reversible capacity of 630 mAh/g after 20 cycles.

The Electrochemical Behavior And Determination Of Carbendazim On Iron Montmorillonite Modified Electrode, Xiao-Li Jiang, Rong Li, Xiao-Ying He, Jiang Li, Ying Li

Journal of Electrochemistry

The FeCl3 modified clay electrode was made.The electrochemical behavior of carbendazim(BCM) on the modified electrode was studied by cyclic voltammetry.The impacts of pH,scan rate and dosages of modifier were discussed and the important kinetic parameters of the electrochemical process were determined.The results indicated that the process was controlled by diffusion.The effective area of FeMM-CMC/GCE(A)=0.027 cm2,the transfer electron numbers(n)=2 and the diffusion coefficient(D)=5.115×10-6cm2/s.Under the optimized conditions,a good linearity was found between the first order derivative of peak current and concentration of BCM in the range of 2.00×10-5～8.00×10-4mol/L,with i′p=-8.045×10-7-0.0237c,correlation coefficient R=-0.9965,and the detect limitation of 2.41×10-6 mol/L.The recovery of BCM was detected …

Voltage Delay On Li/Socl_2 And Bcx Cells During Discharge, Shu-Tao Liu, Yi-Ping Wu, Hong-Hua Ge, Guo-Ding Zhou

Journal of Electrochemistry

The impedance change of both lithium and carbon electrodes during the process of discharge was studied by AC impedance spectroscopy.It shows that the impedance of lithium electrode at initial stage was reduced by 80%～90% and kept nearly unchanged after wards;the carbon electrode impedance initially did not change much but quickly increased just before the end of discharge.The improvement of voltage delay might be related with the higher open-circuit voltage of BCX cell.It is suggested that the voltage delay problem may be solved by the application of supercapacitor.

Power Characteristics Of The Energy Storage System Based On All-Vanadium Solution, Jun-Ping Hu, Qi Zhang, Xi Yang, Yi-Ning Shi, Ming-Sen Zheng, Quan-Feng Dong, Zhao-Wu Tian

Journal of Electrochemistry

The energy storage system based on all-vanadium solution was studied for high power applications.The influences of the electrode thickness,the electrolyte concentration and velocity in performance of the storage system were investigated in detail.The power density could achieve 3121 W/L at the current density 750 mA/cm2 under the optimal conditions.

Preparation And Characterization Of Tin-Nickel Alloy Electromagnetic Shielding Fabric, Ke-Jing Chu, Wei Wang, Bin Sun, Mei-Fang Zhu

Journal of Electrochemistry

A soft electromagnetic shielding fabric was successfully prepared by electroplating tin-nickel alloy on the Cu-plated PET fabric in potassium pyrophosphate system.Results show that the different tin content and different colour can be obtained by changing the ratio of metals in bath.Better corrosion resistance and anti-tarnishing were achieved with the fabric consisting of 68.96% Sn.The tin-nickel alloy surface for the electromagnetic shielding fabric had excellent conductivity,softness,permeability and soft luster、non-sensitized to the human body.Thereby it has broad prospect in EMI field and shielding clothing.

Electrosynthesis Of 2,2-Dimethylolpropionic Acid, Hong-Yan Sun, Zhen-Hai Liang

Journal of Electrochemistry

The Ti/SnO2+Sb2O4/PbO2 electrode was prepared.The structure phase and valent state were characterized by means of XRD and XPS.The 2,2-dimethylolpropionic acid was synthesized on the Ti/SnO2+Sb2O4/PbO2 anode by direct electro-oxidation of 2,2-dimethylolpropionaldehyde.The product and crude material were analyzed by HPLC,the effects of the concentration of 2,2-dimethylolpropionaldehyde,pH,potential and reaction temperature were studied.The results showed that the optimum conditions were anode potential 1.8 V,pH=1,reaction temperature 15℃ and 2,2-dimethylolpropionaldehyde concentration 0.10mol/L.Under the optimum conditions,the selectivity of 36%,the current efficiency of 28% and the conversion of 58% were reached.The reported method provides a new route for the synthesis of 2,2-dimethylol propionic acid.

19~(Th) International Symposium Of Fine Chemistry And Functional Polymers (Fcfp-Xix) & Iupac 5~(Th) Internaitonal Symoposium On Novel Materials And Synthesis(Nms-V)

Journal of Electrochemistry

No abstract provided.

Information Of The Electrochemistry And Relative Science & Technique Conferencein China

Journal of Electrochemistry

No abstract provided.

Education In The Environment: A Strategy For Continued Interagency Outdoor Education Programming: Quarterly Progress Report: Period Ending February 28, 2009, Environmental Education Strategy For Nevada

Reports (PLI Education)

Highlights of the university's focused efforts during the past three months include the following:

• Fourteen people from the Fall 2008 cohort are currently completing the internship portion of the Nevada State Certification in Environmental and Interpretation Certification Program.
• Planning continues for the mobile exhibit program to support and deliver SNAP messages.
• An Hispanic Community education program - Families in Nature- is being planned for April25, 2009.
• Forever Earth was scheduled for 19 days and benefited 442 individuals.
• Seven Discover Mojave Outdoor World events were conducted for 132 participants.

Satellite-Based Fusion Of Image/Inertial Sensors For Precise Geolocation, Neil R. Jesse

Theses and Dissertations

The ability to produce high-resolution images of the Earth’s surface from space has flourished in recent years with the continuous development and improvement of satellite-based imaging sensors. Earth-imaging satellites often rely on complex onboard navigation systems, with dependence on Global Positioning System (GPS) tracking and/or continuous post-capture georegistration, to accurately geolocate ground targets of interest to either commercial and military customers. Consequently, these satellite systems are often massive, expensive, and susceptible to poor or unavailable target tracking capabilities in GPS-denied environments. Previous research has demonstrated that a tightly-coupled image-aided inertial navigation system (INS), using existing onboard imaging sensors, can provide …

Homogeneous Operators In The Cowen-Douglas Class., Subrata Shyam Roy Dr.

Doctoral Theses

Although, we have used techniques developed in the paper of Cowen-Douglas [18, 20], a systematic account of Hilbert space operators using a variety of tools from several different areas of mathematics is given in the book [26]. This book provides, what the authors call, a sheaf model for a large class of commuting Hilbert space operators. It is likely that these ideas will play a significant role in the future development of the topics discussed here.

Preparation And Performance Of Co And La Co-Doped Li-Rich Lithium Manganate, Da-Qiao Zhou

Journal of Electrochemistry

The cathode material of Li1.1Co0.02La0.01Mn2O4 was successfully synthesized by the method of co-precipitation followed by a solid state reaction.In the sintering temperature range of 700～850 ℃,X-ray diffraction(XRD) results showed a single phase of each material and the increase of crystallization degree,and scanning electron microscopic(SEM) images indicated that the particle size increased and the specific surface area decreased,respectively,with increasing the sintering temperature.Due to its lower polarization resistance,the Co and La co-doped lithium-rich lithium manganate(sintered at 800 ℃) positive electrodes showed the most promising electrochemical performance.The capacity retention after 50 cycles reached 98.5%.

Look Behind The Scenes With The Ti-Nspire, Lisa Yocco

Lisa S. Yocco

No abstract provided.

Intermolecular Electron-Transfer Catalyzed On Nanoparticle Surfaces, Am Carver, M De, H Bayraktar, S Rana, Vm Rotello, Mj Knapp

Vincent Rotello

Surface-functionalized nanoparticles enhance the rate of electron transfer (ET) between Cyt c(Fe2+) and Co(phen)33+ by a factor of 105 through simultaneous electrostatic binding of an ET donor and acceptor.

Samats: Texture Extraction Explained, Joe Hegarty, James Carswell

Conference papers

The creation of detailed 3D buildings models, and to a greater extent the creation of entire city models, has become an area of considerable research over the last couple of decades. The accurate modeling of buildings has LBS (Location Based Services) applications in entertainment, planning, tourism and e-commerce to name just a few. Many modeling systems deployed to date require manual correspondences to be made across the image set in order to determine the models 3D structure. This paper describes SAMATS, a Semi-Automated Modelling and Texturing System, which has the capability of producing geometrically accurate and photorealistic building models without …

Classifying Still Faces With Ultrasonic Sensing, Phillip J. Mckerrow, K. K. Yoong

Phillip McKerrow

The echo of a chirp of ultrasonic energy from an object contains information about the geometry of that object: relative depth of surfaces and approximate area of those surfaces. A human face has complex geometry that produces a distinctive echo. In this paper, we report initial research into whether there is sufficient information in the echo to recognize a still face. Potential features for classification are identified using a facial model. The classification results for 10 faces encourage future research with a larger number of faces and with moving faces.

Acoustic Flow, Phillip J. Mckerrow

Phillip McKerrow

As an echolocating sensor moves through an environment the pattern of echoes reflected by objects to that sensor changes continuously, creating acoustic flow. Acoustic flow has been observed in both bats and humans. In this paper, we develop a theory of acoustic flow, and discuss measuring it with a Continuous Transmission Frequency Modulated (CTFM) ultrasonic sensor.

Developing Real-Time Systems In Java On Macintosh, Phillip J. Mckerrow

Phillip McKerrow

In this paper, we examine the advantage of writing real-time applications and operating systems in typesafe languages, such as Java. In this context, we look at the issues of using Java in real-time systems and the development tools available on Macintosh computers. Finally, we explore the potential of the Sun SPOT system: a credit-card sized Java computer with input/output, and a wireless network, that runs the Squawk JVM. It is planned to be released in Australia in the third quarter of 2007.

Research Into Navigation With Ctfm Ultrasonic Sensors, Phillip J. Mckerrow

Phillip McKerrow

Our goal is to develop a navigation system for a mobile robot that mimics human navigation. To achieve this goal the robot has to perceive sufficient information about its environment to determine where there are safe paths to travel. Blind humans using ultrasonic mobility aids have achieved excellent navigation. First, we look at the quality of ultrasonic sensing and its suitability for navigation. Then we describe examples from our research into navigation. The paper finishes with a description of current work on corridor following.

Developing Real Time Applications With Java Based Sun Spot, L. Chen, Phillip J. Mckerrow, Q. Lu

Phillip McKerrow

Most researchers develop real-time applications with C, including programming hardware with C and using a Real Time Operating System (RTOS) that is written in C to manage the task environment. In this paper, we research a different approach by using Java to develop a real-time application. We implement an example real-time project, onboard computation of a coaxial helicopter Lama, with a Java based Sun SPOT to control the hardware and a Java RTOS (JARTOS) running on top of the Sun SPOT to manage the processes. This project enables us to answer several questions regarding to real-time system development with the …