Engineering Commons^™

Initial Stage Of Atmospheric Corrosion Of Ndfeb(M35) In A Simulated Marine Atmosphere, Chun-Ling Li, Yuan-Tai Ma, Ying Li, Fu-Hui Wang

Journal of Electrochemistry

This study detailed the atmospheric corrosion behaviour of sintered NdFeB(M35) in a simulated marine atmosphere with 80% relative humidity(RH).The dissolution and subsequent reaction of NaCl particles cause the attack of NdFeB.The corrosion presented three representative types:if the electrolyte covered magnetic phase and Nd-rich phase,the Nd-rich phase was corroded firstly due to galvanic effect;if the electrolyte covered magnetic phase,magnetic phase was corroded along the grain boundary;if the electrolyte located near the position of defects,corrosion progressed along with the defect because of low concentration of oxygen inside the defect.With corrosion progressing,local corrosion areas were mutually connected,with Nd-rich phase and grain boundary being …

Photoelectrochemical Properties Of N, S, And Cl Modified Nano Tio2 Thin Films, Hong Yun, Chang-Jian Lin, Jing Li, Rong-Gui Du

Journal of Electrochemistry

The nitrogen(N),sulfur(S) and chlorine(Cl) modified nano TiO₂ thin films were prepared by adding Ti(O-n-Bu)₄ as the precursor into concentrated HNO₃,H₂SO₄ and HCl Solutions,respectively,on different substrates in a sol-gel process.The photoelectrochemical performances of N,S and Cl modified nano TiO₂ thin films have been studied by UV-vis(DRS),photocurrent curves,EIS and OCP-time curves.N-modified TiO₂ nano films show better surface structure,which helps to improve the quantum efficiency of nano TiO₂ thin films.

Hydrothermal Reduction Synthesis Of Lifepo4 And Its Electrochemical Performance, Hong-Li Zou, Guang-Hui Zhang, Pei-Kang Shen

Journal of Electrochemistry

The cathode materials of LiFePO₄ were prepared via a hydrothermal reduction method using FeCl₃ as Fe source and iron as a reducing agent.The results showed that ferric salt could be reduced to ferrous salt completely under the hydrothermal condition and pure-phase LiFePO₄ was obtained based on the test results of XRD and FTIR.Carbon-coated LiFePO₄ was synthesized by pyrolysisng glucose at high temperature.The morphologies of pure LiFePO₄ displayed cluster-like while the LiFePO₄/C displayed sphere-like particles.The electrochemical test showed that the LiFePO₄/C had good rate performance,while LiFePO₄ delivered much lower discharge capacity.

Effects Of Solvents And Electrolyte Salts On The Electrochemical Reduction Of Oxygen In Non-Aqueous Electrolytes, Yan-Yan Tian, Wei Wu, Jun Gao, Yong Yang

Journal of Electrochemistry

The electrochemical reduction processes of oxygen in different non-aqueous solvents such as acetonitrile(MeCN),propylene carbonate(PC) and their mixtures were investigated by cyclic voltammetry method.The results indicated a one electron reduction of oxygen to O^2-occured in these systems as a first step reduction,no matter whether in tetrabutylammonium hexafluorophosphate(TBAPF₆)/MeCN or TBAPF₆/PC electrolyte.However,the CV curves in 0.1 mol·L^-1 TBAPF₆/MeCN showed a couple of reversible redox peaks,indicating that the reduction process of oxygen was irreversible in the 0.1 mol·L^-1 TBAPF₆/PC electrolyte.In the PC-based electrolyte,the reduction current peak reduced largely and the oxidation peak …

Corrosion Electrochemical Behavior Of Am60 Magnesium Alloys In Automobile Engine Coolants, Ling-Jie Li, Sha Wang, Yin Xiao, Jun Lan, Jing-Lei Lei, Sheng-Tao Zhang, Fu-Sheng Pan

Journal of Electrochemistry

The polarization measurements and electrochemical impedance spectroscopy(EIS) were used to study the corrosion electrochemical behavior of AM60 magnesium alloys in three kinds of commercial coolants for automobile engine.Results show that the tested commercial coolants are slightly corrosive to AM60 magnesium alloys and their corrosivity varies from coolant to coolant.The coolant C is the least corrosive among the studied commercial coolants and the coolant A is more corrosive than the coolant B and C.The coolant C appears to be the most promising coolant for automobile engine made by magnesium alloys.The coolant resistivity plays an important role in the corrosion of AM60 …

Electrodeposition Of Lead Dioxide From Dluoroborate Solutions, Chun-Mei Kong, Yong-Ming Tang, Wen-Zhong Yang, Xiao-Yuan Yang

Journal of Electrochemistry

The PbO₂ anodes were prepared on platinum from fluoroborate media and its doped solutions by electrodeposition technique.Elecchemical and pysicochemical properties of these PbO₂ films were studied by cyclic voltammetry methods,XRD and SEM.The results showed that the presence of BF₄-increased PbO₂ electrodeposition rate;the prepared lead dioxide consisted of β-PbO₂;the preferential orientation of crystals and surface morphology were affected a lot by doping F-and Fe³⁺.The FB/F-Fe-PbO₂ electrode exhibited regular-shaped layers with compact morphology.Furthermore,increasing current density also change the preferential orientation of PbO₂ crystals.

The Sol-Gel Synthesis And Electrochemical Performance Of Li3V2(Po4)3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai

Journal of Electrochemistry

Li₃V₂(PO₄)₃/C was synthesized by sol-gel method with citric acid as chelate and C sources. Physical and electrochemical performances of as-prepared materials were characterized through XRD, SEM and galvanostatic charge-discharge tests,etc. The results showed that products produced by calcining at 800 ℃ for 12 h had a single phase crystal structure and relatively small particle sizes with uniform distribution. At 0.1 C, 0.5 C and 1 C, the initial specific discharge capacities were 153.0, 143.1 and 130.6 mAh·g^-1, respectively, and capacity efficiencies were 93.1%, 85.4% and 77.3% after 50 cycles, respectively. …

Research On Nafion/Sio2 Composite Membrane In All Vanadium Redox Flow Battery, Dong-Dong Liu, Mao-Cai Lin, Tao Guan, Qing-Chun Yu

Journal of Electrochemistry

The Nafion117/SiO₂ composite membrane was prepared by sol-gel method.The results showed that,during composite membrane preparation process,the ratio of MeOH and TEOS did not affect the penetration rate of VO²⁺ basically,however,the lowest permeability of 427×10-9cm²/s in the membrane was achieved while hydrolysis time was 10 min and natural drying for 24 h after hydrolysis,which reduced by 52 times than that in Nafion117 membrane.The SEM tests proved that SiO₂ grains grew bigger in the composite membrane during the natural drying,and most of the holes in Nafion117 were filled.Single cell test showed the battery power efficiency was improved …

Effect Of Cldh On Rebar Corrosion Behavior In Chloride Contaminated Neutral Pore Solutions, Yu-Ming Tang, Le Niu, Yu Zuo

Journal of Electrochemistry

he effect of calcined LDH-MgAl-CO₃ on rebar corrosion behavior in chloride ion contaminated neutral concrete pore solutions was investigated in this paper.Corrosion potentials of rebars in pore solutions after treatment with CLDH were higher than before treatment.According to polarization tests,passivated region of rebars in pore solutions after treatment with CLDH was found apparently instead of activation.EIS tests showed that CLDH made the impedance of specimens increase.The measurements of pH and chloride ion concentration after treatment indicated that / of pore solutions decreased by 4～5 magnitude orders.

Preparation And Characterization Of The Silane-Phosphonic Acid Composite Passivation Coating For Electrogalvanized Steel, Yong Guan, Jian-Guo Liu, Chuan-Wei Yan

Journal of Electrochemistry

A new silane-phosphonic acid composite passivation coating process has been developed for the protection of electrogalvanized steel based on N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane(AAPTMS),γ-(2,3-epoxypropoxy)propyltrimethoxy-silane(GPTMS) and 1-hydroxy ethylidene-1,1-diphosphonic acid(HEDP).The results of X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FTIR),potentiodynamic polarization scan,electrochemical impedance spectroscopy(EIS) and neutral salt spray(NSS) tests indicated that the major structure of the prepared silane-phosphonic acid composite passivation coating consisted mainly of Si—O—Si and Si—O—P bonds.The area of white rust was not more than 5% of the total panal after 120 h NSS test,which could be compared favourably with the chromate colour passivation coating.However,the corrosion reaction on the anode of the silane-phosphonic acid composite passivation …

Study Of The 11-Ferrocenylalkanethiol Redox-Induced Structure Changes By Flow-Injection Electrochemical Surface Plasmon Resonance, Xiu-Juan Xiao, Yong-Hui He, Juan Xiang, Bin Ren

Journal of Electrochemistry

Redox-induced orientation changes of self-assembled monolayers(SAMs) of 11-ferrocenylundecanethiol(FcC₁₁SH) were studied by the flow-injection electrochemical surface plasmon resonance(FI-EC-SPR).Results indicated that there existed two mechanisms concerning the redox-induced structure change of the self-assembled monolayer of ferrocenylalkanethiols:the electrostatic repulsion between the positively charged surface and the ferricenium cation and that among the cations led to a decrease in the tilt angle of the alkanethiol chain;upon Fc oxidation,the Fc group rotated from a tilted conformation to a position where the cyclpentyldiene plane became perpendicular to the electrode.

The Roles Of The Width Of Gas/Liquid/Solid Three-Phase Boundary Zone Of Dispersion Water Films In Atmospheric Corrosion Of Metals, Jia Wang, Jing Jiang

Journal of Electrochemistry

The roles of TPB(Three-Phase Boundary) width in the corrosion processes of metals under dispersed water films were investigated by electrochemical techniques combined with contact angle measurement.It is found that both cathodic limiting current density and corrosion current density linearly increases with increasing the TPB width,confirming the important role of TPB width in gas/liquid/solid multiphase corrosion systems.Based on above results,the effect of water film thickness on atmospheric corrosion rate was quantitatively evaluated by the TPB width.

Effect Of Process Parameters On Abnormal Grain Growth During Friction Stir Processing Of A Cast Al Alloy, S. Jana, Rajiv S. Mishra, J. A. Baumann, G. Grant

Materials Science and Engineering Faculty Research & Creative Works

The effects of process parameters and friction stir processing (FSP) run configurations on the stability of nugget microstructure at elevated temperatures were evaluated. Cast plates of an Al-7Si-0.6Mg alloy were friction stir processed using a combination of tool rotation rates and tool traverse speeds. All single pass runs showed some extent of abnormal grain growth (AGG), whereas multi-pass runs were more resistant to AGG. Additionally, higher tool rotation rate was found to be beneficial for controlling AGG. These effects were analyzed by comparing the result of this work with other published results and AGG models. © 2010 Elsevier B.V.

Novel Design Of Fuel Cell Bipolar For Optimal Uniform Delivery Of Reactant Gases And Efficient Water Removal, Susanta Das, Jayesh Kavathe, Panini K. Kolavennu, Joel Berry

Mechanical Engineering Patents

The flow plate (20) defines stems (76), branches (78), and sub-branches (80) for moving fluid between each of the openings (34, 36) and the active area (42). The openings (34, 36) are trifurcated into two branches (78) and one stem (76) for providing flow of fluid through each of the stems (76) equal to the combined flow through co-diverging of the branches (78). The stems (76) have a minimal cross-sectional flow area less than the combined minimal cross-sectional flow area of the co-diverging of the branches (78). The stems (76) are bifurcated into two branches (78). The branches (78) have …

Evolving Fuzzy Optimally Pruned Extreme Learning Machine: A Comparative Analysis, Federico Montesino Pouzols, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

This Paper Proposes a Method for the Identification of Evolving Fuzzy Takagi-Sugeno Systems based on the Optimally Pruned Extreme Learning Machine (Op-Elm) Methodology. We Describe Elm Which is a Simple Yet Accurate and Fast Learning Algorithm for Training Single-Hidden Layer Feed-Forward Artificial Neural Networks (SLFNS) with Random Hidden Neurons. We Then Describe the Op-Elm Methodology for Building Elm Models in a Robust and Generic Manner. Leveraging on the Previously Proposed Online Sequential Elm Method and the Op-Elm, We Propose an Identification Method for Self-Developing or Evolving Neuro-Fuzzy Systems. This Method Follows a Random Projection based Approach to Extracting Evolving Fuzzy …

A Bit Serial Approach To Massively Parallel Floating Point Operations On An Fpga, Duane Marcy, Fred Schlereth, Parija Kshirsagar, Anvith Katte Mahabalagiri

Electrical Engineering and Computer Science - All Scholarship

In this paper we discuss the pros and cons of bit serial arithmetic for performing mathematical operations for signal processing and scientific computations on an FPGA.  We describe our formulation of the architecture for such massively parallel systems, the advantage being that it requires no parallel programming in the traditional sense. We describe a pseudo floating point bit serial circuit which is less complex than full precision floating point and show that it is suitable for many applications. We conclude with several application examples and show that a bit serial implementation can be competitive with a high speed parallel implementation.

Virtual Coatings Application System, Jason M. Ebsensberger, Michael J. Bolick, Richard J. Klein Ii, Eric C. Peterson, Chad J. Zalkin, James B. Fisher, Leslie C. Hughes

Patents (University of Northern Iowa)

A virtual coatings application system has several features to enhance the realism of simulated spray painting. The system generally includes a display screen on which is defined a virtual surface (such as a truck door) that is intended to be virtually painted or coated by the user. Alternatively, the system includes a head-mounted display unit that displays a virtual spray painting environment in which the virtual surface is defined. The user operates an instrumented spray gun controller that outputs one or more signals representing data as to the status of the controls on the spray gun controller. The system also …

Virtual Coatings Application System, Jason M. Ebensberger, Michael J. Bolick, Jeremiah G. Treloar, Richard J. Klein Ii, Eric C. Peterson, Chad J. Zalkin, James B. Fisher, Leslie C. Hughes

Patents (University of Northern Iowa)

A virtual coatings application system has several features to enhance the realism of simulated spray painting. The system generally includes a display screen on which is defined a virtual surface (such as a truck door) that is intended to be virtually painted or coated by the user. The user operates an instrumented spray gun controller that outputs one or more signals representing data as to the status of the controls on the spray gun controller. The system also has a motion tracking system that tracks the position and orientation of the spray gun controller with respect to the virtual surface …

Dual-Scale Modeling Of Two-Phase Fluid Transport In Fibrous Porous Media, Alireza Ashari

Theses and Dissertations

The primary objective of this research is to develop a mathematical framework that could be used to model or predict the rate of fluid absorption and release in fibrous sheets made up of solid or porous fibers. In the first step, a two-scale two-phase modeling methodology is developed for studying fluid release from saturated/unsaturated thin fibrous media made up of solid fibers when brought in contact with a moving solid surface. Our macroscale model is based on the Richards’ equation for two-phase fluid transport in porous media. The required constitutive relationships, capillary pressure and relative permeability as functions of the …

Quantification Of Functional Near Infrared Spectroscopy To Assess Cortical Reorganization In Children With Cerebral Palsy, Fenghua Tian, Mauricio R. Delgado, Bilal Khan, Sameer C. Dhamne, George Alexandrakis, Mario I. Romero, Linsley Smith, Dahlia Reid, Hanli Liu, Nancy J. Clegg

Bioengineering Faculty Publications - Archive

No abstract provided.

Bandwidth-Efficient Mimo Underwater Acoustic Communications With Frequency-Domain Equalization, Jian Zhang, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a bandwidth-efficient frequency-domain equalization (FDE) for single carrier (SC) underwater acoustic (UWA) communications with multiple transducers and hydrophones. the proposed algorithm implements an overlapped-window FDE by partitioning a large block into small subblocks. a decision-directed channel estimation scheme is also proposed to track the channel variation by the detect symbols. the proposed algorithm is tested by undersea data collected during the Rescheduled Acoustic Communications Experiment (RACE) in March 2008. the experimental results demonstrate the proposed receive algorithm effectively tracks the time variation of the channel impulse responses and significantly improves the performance of uncoded bit error rate …

Turbo Detection For Mobile Mimo Underwater Acoustic Communications, Jun Tao, Yahong Rosa Zheng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

Turbo detection for mobile transceivers is proposed for high data-rate single-carrier multiple-input, multiple-output (MIMO) underwater acoustic (UWA) communications. the proposed detection scheme employs a MIMO Doppler preprocessor and a low-complexity MIMO turbo linear equalizer (LE). the Doppler preprocessor estimates the motion-induced Doppler shift and compensates it via symbol resampling. the preprocessed signal is then detected by the MIMO turbo LE that utilizes soft-decision minimum mean square error (MMSE) linear equalization with maximum a posteriori probability (MAP) channel decoding, thus improving the detection performance iteratively while maintaining low complexity. the proposed turbo detection scheme has been tested by field trial data …

Lean Manufacturing As A Source Of Competitive Advantage, Ryan Scott Williams

Theses and Dissertations

The productivity advances generated from lean manufacturing are self-evident. Plants that adopt lean are more capable of achieving high levels of quality, shorter lead times, and less waste in the system. While it seems logical that higher levels of productivity and quality, as is common in lean companies, should result in positive financial performance, the research community has failed to establish the financial profitability of lean. Those researchers who have studied the financial returns issue report varying results. The goal of this research was to determine if a connection exists between lean and financial success and to discover why so …

Understanding The Economics Of Transportation In Utah, Jeremy E. Searle

Theses and Dissertations

Understanding the economic impacts of transportation projects in Utah is essential for decision makers, officials, and stakeholders as they determine the best course of action for the state. Economic impacts can guide decisions of future projects and help explain past economic fluctuations. This study develops a process that can be used to identify the economic impacts of transportation projects in Utah and quantify the relationship between transportation and these impacts. Accomplishing the objectives of this study are a product of: 1) performing a comprehensive literature review, 2) collecting data and establishing analysis methods, 3) completing a statistical analysis and breakdown …

Attitudes Of Health Professionals To Electronic Data Sharing Within An Integrated Care Electronic Health Record (Icehr), Charyl O'Malley, Damon Berry, Mary Sharp

Conference Papers

It is estimated that 98,000 people die in hospitals yearly in the USA as a result of medical errors (Agency for Healthcare Research and Quality, 2009). Electronic Health Records (EHR) can offer improved patient safety. EHRs are being implemented by many countries, however, not all health professionals have welcomed them (MORI Social Research Institute, 2006). As outlined in the National Health Information Strategy (NHIS) document, Ireland has plans to introduce an EHR. Attitudes of health professionals are a significant factor for the successful implementation and adoption of a new clinical information system. This study aimed to gauge the attitude of …

Improved Measurement And Separation Techniques For Interior Near-Field Acoustical Holography, Zachary A. Collins

Theses and Dissertations

Recent advances in near-field acoustical holography (NAH) have expanded the theory to interior spaces where multiple sources and/or reflections are present. In 1990, Tamura presented the spatial Fourier transform separation method to measure the reflection coefficient at oblique angles using two measurement planes in the wave number domain. This paper adapts the spatial Fourier transform separation method for application in interior NAH. A practical exploration of important experimental parameters is performed, which include the relative amplitudes of primary and disturbing sources, the measurement plane separation distance, and an acceptable noise floor. This technique is successfully applied in a reverberant environment …

Straightness Of Growth For Carbon Nanotube Microelectromechanical Systems, Kellen S. Moulton

Theses and Dissertations

The purpose of this research is to examine the effect of iron catalyst thickness on the straightness of growth of carbon nanotube microelectromechanical systems (CNT-MEMS). One of the key benefits of CNT-MEMS is that they can potentially have very high aspect ratios. One of the challenges in attaining these high aspect ratios is maintaining device straightness; as these devices get taller, the edges tend to curve rather than grow straight vertically. Scanning electron mi- croscope images of samples grown using various iron catalyst thicknesses show that both straight growth and relatively good edge definition can be achieved using iron thicknesses …

A New Statistical Procedure For Validation Of Simulation And Stochastic Models, Robert G. Sargent

Electrical Engineering and Computer Science - All Scholarship

We describe a new statistical procedure for validating simulation and analytic stochastic models using hypothesis testing when the amount of model accuracy is specified. This procedure provides for the model to be accepted if the difference between the system and the model outputs are within the specified ranges of accuracy. The system must be observable to allow data to be collected for validation.

Energy Storage And Management For A Small Series Plug-In Hybrid Electric Vehicle, Liqin Ni

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Plug-in hybrid electric vehicles (PHEVs) are gaining increasing interest for both residential and commercial transportation applications. In PHEV design, energy storage system (EES) is a critical component which will impact the overall design efficiency, performance, cost and etc. This dissertation aims to design an advanced energy storage system for a small plug-in hybrid electric vehicle, whose performance will approach very closely to the optimal possible, in terms of energy efficiency and acceleration, for passenger road vehicles application. Moreover, practical automotive requirements are considered during ESS design, such as cost, life time, safety and volume.

This dissertation utilizes ultracapacitors in conjunction …

Terminology Enhanced Ehr: Integration Of Archetypes And Terminology, An Implementation Experience, Sheng Yu, Damon Berry

Reports

The integration of terminology and EHR information models is an important step in the journey towards semantic interoperability. Archetypes and two-level models for EHRs provide a mechanism that not only applies constraints on clinical content but also ensures effective terminology binding. However the lack of a standardised mechanism to bind terminology to the EHR and the difficulty of systematically coding clinical content, has led to a number of possible implementation choices. This study presents a review of the problems that may occur when working with modern terminology systems and discusses some related state of art technologies. The paper aims to …