Engineering Commons^™

Waves In Microstructured Solids: A Unified Viewpoint Of Modelling, Arkadi Berezovski, Juri Engelbrecht, Mihhail Berezovski

Publications

The basic ideas for describing the dispersive wave motion in microstructured solids are discussed in the one-dimensional setting because then the differences between various microstructure models are clearly visible. An overview of models demonstrates a variety of approaches, but the consistent structure of the theory is best considered from the unified viewpoint of internal variables. It is shown that the unification of microstructure models can be achieved using the concept of dual internal variables.

Prepartion And Characterization Of Spr Au Substrate Using Wet Chemical Plating, You-Chen Zhou, Yan-Yan Wang, Zhi-Fang Ma, Yan-Xia Jiang, Jin Qiu, Shi-Gang Sun

Journal of Electrochemistry

The present study developed a preparation method of SPR gold substrate based on water phase operation.Firstly,on the glass modified by APTMS we self-assembed a gold colloid monolayer as the catalyst bed;Secondly,using the chemical plating technique,we made the gold film increase equably within the namometer range to obtain the proper shape and thinkness of the gold film required by the SPR.The analysis results of UV-vis and TEM demonstrated that the diameter of the monolayer formed from gold nanoparticles was 2.5 nm.Moreover,SEM showed that the nanoparticle prepared by electroless gold plating was uniformly distributed,whose diameter was 40 nm.The SPR flow injection experiment …

Preparation And Electrochemical Properties Of Sn Thin Film As Anode Materials For Lithium-Ion Batteries, Hong-Mei Bai, Zhan-Liang Tao, Fang-Yi Cheng, Jun Chen

Journal of Electrochemistry

Sn thin films as the anode materials of Li-ion batteries were prepared by vacuum-evaporation method on the copper foam substrate. The phase structure,surface morphology and electrochemical property of the as-prepared films were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM), and galvanostatic cycling. The results showed that three-dimensional structure of copper foam substrate enhanced the adhesion strength between the active material and the substrate, under the same substrate temperature, the particles became bigger with the increasing of evaporation time, while their electrochemical property decreased, under the same evaporation time, the particles didn′t changed obviously with the increasing of substrate temperature,while their cycle …

Electrochemical Double-Layer Capacitors Using Phenolic Resin-Based Carbon Fibers, Rong Xue, Jing-Wang Yan, Ying Tian, Bao-Lian Yi

Journal of Electrochemistry

Phenolic resin-based activated carbon fiber(ACF) was prepared by KOH activation.The electrochemical properties of pulverized phenolic resin-based carbon fiber(P-ACF) were examined in 6 mol·L^-1 KOH compared with that of the original ACF.P-ACF exhibited a better capacitive behavior and showed a larger specific capacitance(200 F·g^-1) as well as a lower capacitance decrease at high current densities.The pore resistance for ion migration(Rp) in P-ACF was lower(2.96 Ω) than that in ACF(4.65 Ω).Pulverization increased the exposure of the cross section,lowered the contact resistance between the carbon fibers and decreased the pore resistance for ion migration.

Low-Temperature Performance Of Li-Ion Battery With Fluoroethylene Carbonate Electrolyte, Chun-Wei Yang, Feng Wu, Bo-Rong Wu, Yong-Huan Ren, Jing-Wen Yao

Journal of Electrochemistry

The low temperature performance of electrolytes containing FEC including FEC+EMC, EC and PC, as well as the compatibility of electrolytes with LiFePO₄ anode and with MCMB cathode were investigated.The electrolyte exhibits a high value of ionic conductivity at low temperature.The stability of cathode was enhanced by the formation of SEI film at 1.6 V as a result of FEC reaction. The infrared spectra showed that FEC can suppress decomposition of other solvents during SEI formation, and lower the resistance of SEI on MCMB cathode. The electrochemistry test indicates that Li-ion batteries with FEC electrolyte display high capacity at low …

Influence Of Electric Field On The Adsorption And Bioactivity Of Hemoglobin On A Macroporous Gold Electrode, Cui-Hong Wang, Yi-Bing Kong, Xing-Hua Xia

Journal of Electrochemistry

The adsorption and bioactivity of proteins at interfaces have been widely studied due to their important role in the construction of biosensors,bioelectronics and biofuel cells.Interfacial electric field is one of the important factors which could affect the adsorption and bioactivity of proteins at materials surfaces.It could dramatically change the adsorption density,molecular conformation and orientation at material surfaces.In this paper,the influence of interfacial electric field on the adsorption kinetics and bioactivity of hemoglobin(Hb) on a three-dimensional(3D) macroporous gold electrode surface has been studied using electrochemical methods and infrared spectroscopy.It was found that the interfacial electric field created excess surface charge which …

Synthesis Of Mesoporous Nickel Oxide For Supercapacitor Application, Xuan-Xuan Chen, Zhen-Zhen Zhao, Deng-Chao Wang, Zhong-Jie Huang, Wen-Bin Ni, Li Yu, Jian-Wei Zhao

Journal of Electrochemistry

Mesoporous nickel oxide has been synthesized by calcining metal-organic coordination precursor.Transmission electron microscopy and BET test showed that the prepared NiO had a regular morphology and displayed a narrow size distribution.Electrochemical tests revealed that such mesoporous NiO had a specific capacity of 72 F·g^-1 at the current of 2.0 A·g^-1.Futhermore,the material showed excellent cycle-life stability.There was no degradation of capacitance after 1000 cycles.

A Titanium-Supported Nanoporous Pd Electrocatalyst For Methanol Oxidation, Feng-Juan Niu, Qing-Feng Yi

Journal of Electrochemistry

Titanium-supported nanoporous palladium electrode(nanoPd /Ti) was prepared by a hydrothermal process in the presence of the ligand EDTA and using formaldehyde as reducing agent.SEM images showed that the size of Pd particles was about 60 nm and the Pd particles were connected with each other to form a three-dimensional network structure.Cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS) were applied to evaluate the electrocatalytic activity of the nanoPd/Ti electrode towards methanol oxidation in alkaline solution.CV results showed that the nanoPd /Ti electrode presented high anodic peak densities and a low onset potential for methanol oxidation.Also nanoPd /Ti electrode showed excellent CO tolerance …

Electrocatalytic Oxidation Of Hydrazine At Rutin Carbon Nanotubes Modified Electrode, Hong-Fang Zhang, Qing-Lin Sheng, Jian-Bin Zheng

Journal of Electrochemistry

The electrochemical behavior and electrocatalytic oxidation of hydrazine on rutin multiwall carbon nanotubes modified glassy carbon electrode were studied by cyclic voltammetry.The experimental results indicated that the electrode exhibits good electrocatalytic activity to hydrazine at a reduced oxidation potential of 262 mV.The amperometric response of the modified electrode showed linear increase after successive addition of hydrazine in the concentration range of 2.5×10^-6~1.0×10^-4 mol·L-1 with a detection limit of 5×10^-7 mol·L^-1.

Applications Of Raman Spectroscopy Technique In Lithium Ion Batteries, Liang Zhao, Yong-Sheng Hu, Hong Li, Zhao-Xiang Wang, Hong-Xing Xu, Xue-Jie Huang, Li-Quan Chen

Journal of Electrochemistry

The Raman spectroscopy has been widely used in the study of lithium ion batteries.In this short review,we gave some examples of the applications of Raman spectroscopy in the study of electrode materials including carbonaceous materials,spinel LiM_xMn_2-x O₄,LiFePO₄,as well as polymer electrolytes,room temperaturemolten salt electrolytes and the solid-electrolyte interphase layers.The advantages and disadvantages of the ex-situ and in-situ Raman spectrum techniques are discussed.Using new Raman techniques to investigate Li-ion batteries are suggested.

Electrochemical Performance Of Polytriphenylamine As A Novel Non-Aqueous Supercapcitor Cathode Material, Qiu-Jie She, Zhi-Kai Wei, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

The PTPAn/active carbon compounds were synthesized by heterogeneous precipitation method.The SEM results show that the size of the PTPAn decreases from about 150 nm to few ten nanometers after being incorporated with active carbon.The PTPAn/active carbon compounds have excellent rate and cycling performance:the discharge capacity increases from 88.5 mAh/g to 105 mAh/g at 0.5 C charge/discharge rate and can reach to 70 mAh/g even at 40 C charge/discharge rate.And the capacity retention of the PTPAn/active carbon compounds remain almost unchanged after 1000 cycles at 40 C charge/discharge rate.

Novel Anion Exchange Membranes Base On Copolymer Of 2-(Diethylamino) Ethyl Methacrylate And Fluoro-Polyacrylate For Alkaline Direct Methanol Fuel Cells, Yan-Mei Zhang, Jun Fang, Ge Yan, Yong-Ze Zhuang

Journal of Electrochemistry

Anion exchange membrane fuel cells,which use anion exchange membranes as polyelectrolytes,have attracted more and more research interests recently.In this work,a series of hydroxyl-conducting anion-exchange membranes based on the copolymer of 2-(Diethylamino)ethyl methacrylate and fluoro-polyacrylate were prepared by radical polymerization,and their potential applications in alkaline fuel cells were assessed.It was shown that the ionic conductivity of the membranes reached 10^-2 S·cm^-1 at room temperature,while the methanol permeability was lower than 10^-7 cm²·s^-1.The maximum power density of fuel cell assembled with this membrane was achieved to be 43.2 mW·cm^-2 at room temperature,indicating possible application …

Electrooxidation Of Methanol On Multilayer Films Of Polypyrrole-Platinum Electrode, Ling Zhang, Long-Zhen Zheng

Journal of Electrochemistry

Multilayer films of polypyrrole-platinum electrode were fabricated by cyclic voltammetric technique.Electro-oxidation of methanol on this electrode was investigated with the aid of cyclic voltammetry and chronoamperometry.Results demonstrated that the multilayer of polypyrrole-platinum electrode behaved better electrocatalytic performance for electro-oxidaton of methanol and better poison resistant.Furthermore,with the increase of deposited platinum loadings,the rate controlling step on electro-oxidation reaction of methanol was changed from CO oxidation to sorption-desorption of hydrogen.

Electrochemical Capacitive Performance Of Polyaniline Electrode With Different Electrolytes, Yong-Tao Tan, Fen Ran, Ling-Ren Wang, Ji Liu, Ling-Bin Kong, Yong-Chun Luo, Long Kang

Journal of Electrochemistry

The polyaniline(PANi) for supercapacitor was prepared by chemical-oxidative polymerization.The SEM,FTIR data and electrochemical performance showed that,polyaniline nanoparticles were formed which were about 50 nm;the specific capacitances of PANi were 404 F/g,208 F/g and 279 F/g in 1 mol/L H₂SO₄,NaNO₃ and KOH,respectively,when the current density was 5 mA/cm².The concentrations of H₂SO₄ increased to 2 mol/L or 6 mol/L,the capacitances decreased to 330 F/g or 248 F/g.

Electrochemical Deposition Of Zinc Oxide Crystal Whiskers, Peng-Zeng Lu, Su Li, Jin-Qian Jia, Zhen-Hai Liang

Journal of Electrochemistry

Pine needle ZnO crystal whiskers were electrodeposited by anodization of zinc foil.The crystal whiskers were characterized by scanning electron microscopy(SEM) and X-ray diffraction(XRD) spectroscopy.The results show that the lengths and diameters of ZnO crystal whiskers are 200~300 nm and 20~50 nm,respectively,with the ratio of the length to diameter ranging from 10~15.The whiskers belong to wurtzite ZnO(JCPDS 36-1451) with good crystallinity and high purity.The crystalization behavior of ZnO was studied by cyclic voltammetry.The effects of the surface oxide layer at the zinc substrates and the [Zn(OH)₄]^2-concentration of the aqueous electrolyte on the formation of zinc oxide whiskers …

The Charge-Discharge Properties Of 40 Ah Aerospace Nickel Hydrogen Cell, Hai-Chang Zhang, Wen-Cheng Ming, Xue-Ying Ren, Hui-Juan Li, Hong-Min Fan, Li-Chao Li

Journal of Electrochemistry

In present investigation,40 Ah nickel-hydrogen cell has been manufactured and its charge-discharge properties has been performed.The results indicate that the cell exhibited the best discharge capacity(50 Ah) when the test conditions were between 0~10 ℃,on the other hand,the cell accompanied with temperature being raised to 10 ℃ while the cell was subjected to discharge operating.The cell voltage decreased to -0.2 V and the cell temperature increased continuously during the over-discharge test.The cell voltage was first increased and then decreased,but the cell temperature was climbed rapidly while the cell was performed during the over-charge test.The 40 Ah nickel-hydrogen cell has excellent …

Surface-Enhanced Raman Imaging Of Intracellular Bioreduction Of Chromate In Shewanella Oneidensis, Sandeep P. Ravindranath, Kristene Henne, Dorothea Thompson, Joseph Irudayaraj

Birck and NCN Publications

This proposed research aims to use novel nanoparticle sensors and spectroscopic tools constituting surface-enhanced Raman spectroscopy (SERS) and Fluorescence Lifetime imaging (FLIM) to study intracellular chemical activities within single bioremediating microorganism. The grand challenge is to develop a mechanistic understanding of chromate reduction and localization by the remediating bacterium Shewanella oneidensis MR-1 by chemical and lifetime imaging. MR-1 has attracted wide interest from the research community because of its potential in reducing multiple chemical and metallic electron acceptors. While several biomolecular approaches to decode microbial reduction mechanisms exist, there is a considerable gap in the availability of sensor platforms to …

Teaching On-Line Csc 150, Paula Kurtenbach

ASEE Best Practice Series Presentations

No abstract provided.

First Undergraduate Online Course In Mechanical Engineeringat Sdsu Through D2l, Zhong Hu

ASEE Best Practice Series Presentations

No abstract provided.

Crop Updates 2011 - Weeds, Grant Thompson, Abul Hashem, Catherine Borger, Peter Newman, Mike Ashworth, Glen Riethmuller, David Minkey, Harmohinder Dhammu, David Nicholson, Michael Walsh, Ray Harrington, Nicholas Woods

Crop Updates

This session covers twelve papers from different authors:

1. Herbicides for selective spot spraying application on winter weeds in chemical fallow, Grant Thompson, Landmark/Crop Circle Consulting, Geraldton

2. Management of emerging weeds within the Western Australian wheatbelt, Abul Hashem and Catherine Borger Department of Agriculture and Food

3. Integrated Weed Management (IWM) – it’s all about early sowing of a big crop, Peter Newman, Department of Agriculture and Food

4. Increased water rates improve the performance of trifluralin in minimum tillage systems, Catherine Borger1, Mike Ashworth2, Glen Riethmuller1, David Minkey2, Abul …

Online, Continuous Sensor And Method For Curd Moisture Content Control In Cheese Making, Manuel Castillo, Colette C. Fagan, Colm P. O'Donnell, Donal J. O'Callaghan, Frederick Alan Payne

Biosystems and Agricultural Engineering Faculty Patents

A method is provided for improving quality of cheese produced from a milk batch. A light beam from an incident light source impinges onto a surface of the milk batch, and light backscatter is optically detected during a coagulation process and correlated to an optimum cutting time for the milk coagulum. Next, light backscattered from a curd and whey mixture derived from the milk batch during a syneresis process is optically detected and correlated to an optimum syneresis endpoint. At least one of the backscattered light data, optical parameters developed from analysis of the backscattered light data, and whey fat …

Tuning Lattice Thermal Conductance By Porosity Control In Ultrascaled Si And Ge Nanowires, Abhijeet Paul, Gerhard Klimeck

Birck and NCN Publications

Porous nanowires 􏰎NWs􏰍 with tunable thermal conductance are examined as a candidate for thermoelectric devices with high efficiency. Thermal conductance 􏰎􏱆l􏰍 of porous NWs is calculated using the phonon dispersion obtained from a modified valence force field model. Porosity in the NWs break the crystal symmetry leading to the reduction in ballistic 􏱆l. 􏰐100􏰑 Si and Ge NWs show similar percentage reductions in 􏱆l for the same amount of porosity. The model predicts an anisotropic reduction in 􏱆l in SiNWs, with 􏰐111􏰑 showing the maximum reduction followed by 􏰐100􏰑 and 􏰐110􏰑 for a similar hole radius. The reduction in 􏱆l …

The Composite Materials Manufacturaing Hub - Crowd Sourcing As The Norm, R. Byron Pipes, Gerhard Klimeck, Mark R. Pipes

Birck and NCN Publications

The Composites Manufacturing HUB puts compo- sites manufacturing simulations in the hands of those who need them to invent new and innovative ways to capture the extraordinary benefits of these high perfor- mance products at an acceptable manufactured cost. The HUB provides the user simple browser access to power- ful tools that simulate the actual steps and outcome con- ditions of a complex manufacturing process without the need to download and maintain software in the conven- tional manner. Learning use of the manufacturing simu- lation tools will also be accomplished on the HUB in or- der to allow for continuous …

Radio-Frequency Breast Cancer Imaging Results For A Simplified Cylindrical Phantom, Giuseppe Ruvio, Raffaele Solimene, Antonietta D'Alterio, Max Ammann, Rocco Pierri

Conference Papers

Microwave imaging is a pervasive research field and
is useful in numerous applicative diagnostic noninvasive contexts. This paper focuses on two aspects. First, we perform a numerical investigation to assess the role played by fundamental parameters (i.e. number of sensors, operating frequency bandwidth) on cancer detection. To this end, a simplified cylindrical phantom probed by ideal two-dimensional dipoles (i.e. infinitely long along the axis of invariance) is considered. Second, in order to focus on the role of the antennas, we analyze, still by numerical simulations and for a simplified breast model, how performances vary when a realistic antenna is adopted.

Effects Of Heat Flux On Nucleate Boiling In Microgravity, Andrew Fassman

Presentations

No abstract provided.

The Design And Construction Of A Microgravity Boiling Experiment, Troy Munro

Presentations

No abstract provided.

Cobalt Fischer-Tropsch Catalyst Preparation: Overview Of Preparation Techniques On Alumina Pellets, Brad M. Hancock, Kari M. Cook, William C. Hecker

Student Works

Fischer-Tropsch (FT) synthesis is a reaction used to convert carbon monoxide and hydrogen into high-quality liquid fuels. The FT process has been considered a promising alternative route for producing diesel fuel to meet an increasing demand for oil around the world and more strict limits to regulate auto tailpipe emissions. The U.S. Environmental Protection Agency has demanded a reduction in diesel fuel sulfur content to 15 ppm. While crude oil contains finite amounts of sulfur that needs further removal or treatment before it could be used as a commercial fuel, FT synthesis produces sulfur-free diesel fuel. The reaction takes place …

Identifying Horizontal Gene Transfer Using Anomalies In Protein Structures And Sequences, Venkat Ram B. Santosh

School of Computing: Dissertations, Theses, and Student Research

Genetics has traditionally focused on vertical gene transfer, which is the passing of the genetic material of an organism to its offspring. However, recent studies in genetics increased the awareness that horizontal gene transfer, which is the passing of the genetic material of an organism to another organism that is not its offspring, is also a significant phenomenon. Horizontal gene transfer is thought to play a major role in the natural evolution of bacteria, such as, when several different types of bacteria all suddenly develop the same drug resistance genes. Artificial horizontal gene transfer occurs in genetic engineering.

This thesis …

On The Interaction Between Bathymetry And Climate In The System Dynamics And Preferred Levels Of The Great Salt Lake, Ibrahim Nourein Mohammed, David G. Tarboton

Civil and Environmental Engineering Faculty Publications

The Great Salt Lake is a terminal lake whose level is determined by the balance between inflows and outflows. We examine the causes for multimodality in the distributions of lake level and hence volume and area that have previously been examined from a system dynamics perspective. We focus on the role of bathymetry in the dynamics of this system and show that some of the modes that are observed and that represent preferred system states are attributable to features of the bathymetry described using the topographic area‐volume relationship. Being a terminal lake, the only “outflow” is evaporation, which depends directly …

Interface Trap Density Metrology From Sub-Threshold Transport In Highly Scaled Undoped Si N-Finfets, Abhijeet Paul, Giuseppe C. Tettamanz, Sunhee Lee, Saumitra R. Mehrotra, Nadine Collaert, Serge Biesemans, Sven Rogge, Gerhard Klimeck

Birck and NCN Publications

Channel conductance measurements can be used as a tool to study thermally activated electron transport in the sub-threshold region of state-of-art FinFETs. Together with theoretical Tight- Binding (TB) calculations, this technique can be used to understand the evolution of source-to- channel barrier height (Eb) and of active channel area (S) with gate bias (Vgs). The quantitative difference between experimental and theoretical values that we observe can be attributed to the interface traps present in these FinFETs. Therefore, based on the difference between measured and calculated values of (i) S and (ii) |∂Eb/∂Vgs| (channel to gate coupling), two new methods of …