Interfacial Effects On Droplet Dynamics In Poiseuille Flow,
2011
Purdue University
Interfacial Effects On Droplet Dynamics In Poiseuille Flow, Kendra Erk, Jonathan T. Schwalbe, Frederick R. Phelan Jr., Petia M. Vlahovska, Steven D. Hudson
School of Materials Engineering Faculty Publications
Many properties of emulsions arise from interfacial rheology, but a theoretical understanding of the effect of interfacial viscosities on droplet dynamics is lacking. Here we report such a theory, relating to isolated spherical drops in a Poiseuille flow. Stokes flow is assumed in the bulk phases, and a jump in hydrodynamic stress at the interface is balanced by Marangoni and surface viscous forces according to the Boussinesq–Scriven constitutive law. Our model employs a linear equation of state for the surfactant. Our analysis predicts slip, cross-stream migration and droplet-circulation velocities. These results and the corresponding interfacial parameters are separable: e.g., cross-stream …
Electromagnetic Modeling And Measurement Of Adaptive Metamaterial Structural Elements,
2011
Air Force Institute of Technology
Electromagnetic Modeling And Measurement Of Adaptive Metamaterial Structural Elements, Matthew E. Jussaume
Theses and Dissertations
This document addresses two major obstacles facing metamaterial development: uncertainty in the characterization of electromagnetic field behavior in metamaterial structures and the relatively small operational bandwidth of metamaterial structures. To address the first obstacle, a method of prediction aided measurement is developed and exploited to examine the field interactions within metamaterial devices. The fusion of simulation and measurement techniques enhances the understanding of the physical interactions of fields in the presence of metamaterials. To address the second obstacle, this document characterizes the effectiveness of an adaptive metamaterial design that incorporates a microelectromechanical systems (MEMS) variable capacitor. Applying voltages to the …
Memristive Properties Of Thin Film Cuprous Oxide,
2011
Air Force Institute of Technology
Memristive Properties Of Thin Film Cuprous Oxide, Brett C. Castle
Theses and Dissertations
Memristive properties of thin film copper oxides with different grain sizes were characterized using tunneling atomic force microscopy (TUNA) and optical reflection measurements. The thin films containing copper ions of different chemical states were prepared by thermal oxidation of metallic copper thin films, deposited via magnetron sputtering onto silicon wafer substrates at an elevated temperature for various lengths of time. The TUNA measurements showed a memristive hysteresis in the I-V curves under an applied bias profile with an initial bias of -3.5V, a ramp up to 3.5V, and subsequent return to -3.5V. Histogram analysis of the barrier height distribution for …
An Analytical Model Of Nanometer Scale Viscoelastic Properties Of Polymer Surfaces Measured Using An Atomic Force Microscope,
2011
Air Force Institute of Technology
An Analytical Model Of Nanometer Scale Viscoelastic Properties Of Polymer Surfaces Measured Using An Atomic Force Microscope, Jacob B. Goldberg
Theses and Dissertations
The United States Air Force and the Department of Defense is increasingly interested in nanomaterials. To study these materials, one needs to measure the mechanics of materials on the nanoscale. Over the past few decades the atomic force microscope (AFM) has been used in various methods to establish local surface properties at the nanoscale. In particular, surface elasticity measurements are crucial to understanding nanoscale surface properties. Problems arise, however, when measuring soft surfaces such as polymers and biological specimens, because these materials have a more complex viscoelastic response. This research focuses on modeling an AFM dynamic nanoindentation experiment intended to …
Rheological Characteristics Of Solvent Free Nanofluids: Thermal Transitions And Reactive Curing,
2011
Eastern Michigan University
Rheological Characteristics Of Solvent Free Nanofluids: Thermal Transitions And Reactive Curing, Daniel Chojnowski
Master's Theses and Doctoral Dissertations
Solvent-free nanofluids are a new and exciting class of material that evolved to address the limitations of their predecessors, nanocomposites. One of the most exciting aspects of solvent-free nanofluids is the wide range of tools chemists have to build and study them. Understanding how the structure manipulations impact the rheology of the resulting solvent-free nanofluids is essential if solvent-free nanofluids are truly the technology of the future. This work documents the basic rheological parameters, thermal transitions, and curing kinetics of various solvent-free nanofluids synthesized by Zhiming Qiu and Kejian Bian at the Coating Research Institute at Eastern Michigan University.
Corrosion-Resistant Glasses For Steel Enamels,
2011
Missouri University of Science and Technology
Corrosion-Resistant Glasses For Steel Enamels, Richard K. Brow, Signo Tadeu Dos Reis, Michael L. Koenigstein, Genda Chen
Materials Science and Engineering Faculty Research & Creative Works
A cementitious composite material wherein glass-coated steel rods are positioned in a cementitious matrix. The glass composition for coating the steel reinforcing rods includes between about 33-45 weight percent SiO2, 13.5-19.5 weight percent B2O3, 3.5-4.6 weight percent Al2O3, 4.0-13.5 weight percent K2O, 5.5-15.5 weight percent ZrO2, 8.6-15.9 weight percent Na2O, 4.6-5.1 weight percent CaO, 0.6-0.7 weight percent MnO2, 1.0-1.0 weight percent NiO, and 1.0-1.1 weight percent CoO. The glass composition is typically in compression on the rods at ambient temperatures, has a …
Analysis Of Interband, Intraband, And Plasmon Polariton Transitions In Silver Nanoparticle Films Via In Situ Real-Time Spectroscopic Ellipsometry,
2011
Old Dominion University
Analysis Of Interband, Intraband, And Plasmon Polariton Transitions In Silver Nanoparticle Films Via In Situ Real-Time Spectroscopic Ellipsometry, S. A. Little, R. W. Collins, S. Marsillac
Electrical & Computer Engineering Faculty Publications
The dielectric function of Ag nanoparticle films, deduced from an analysis of in situ real-time spectroscopic ellipsometry (RTSE) measurements, is found to evolve with time during deposition in close consistency with the film structure, deduced in the same RTSE analysis. In the nucleation regime, the intraband dielectric function component is absent and plasmon polariton behavior dominates. Only at nuclei contact, does the intraband amplitude appear, increasing above zero. Both intraband and plasmon amplitudes coexist during surface smoothening associated with coalescence. The intraband relaxation time increases rapidly after surface smoothening is complete, also in consistency with the thin film structural evolution.
Influence Of Electric Field On The Adsorption And Bioactivity Of Hemoglobin On A Macroporous Gold Electrode,
2011
Key Laboratory of Analytical Chemistry for Life Science,School of Chemistry and Chemical Engineering,Nanjing University,Nanjing 210093,China;
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 …
Prepartion And Characterization Of Spr Au Substrate Using Wet Chemical Plating,
2011
Department of Chemistry,College of Chemistry and Chemical Engineering,State Key Lab for Physical Chemistry of Solid Surface,Xiamen University,Xiamen 361005,Fujian,China;
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,
2011
Institute of New Energy and Material Chemistry,Key Laboratory of Advanced Energy Materials Chemistry-Ministry of Education,Nankai University,Tianjin 300071,China;
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 …
Synthesis Of Mesoporous Nickel Oxide For Supercapacitor Application,
2011
School of Chemistry and Chemical Engineering,Key Laboratory of Analytical Chemistry for Life Science(MOE),Nanjing University,Nanjing 210008,China;
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.
Electrochemical Performance Of Polytriphenylamine As A Novel Non-Aqueous Supercapcitor Cathode Material,
2011
State Key Lab of Physical Chemistry of Solid Surfaces,Department of Chemistry,College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,Fujian,China;
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.
Electrochemical Double-Layer Capacitors Using Phenolic Resin-Based Carbon Fibers,
2011
Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,Liaoning,China;
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,
2011
Beijing Higher Institution Engineering Research Center of Power Battery and Chemical Energy Materials School of Chemical Engineering and Environment Science,Beijing Institute of Technology, Beijing 100081,China;
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 …
Novel Anion Exchange Membranes Base On Copolymer Of 2-(Diethylamino) Ethyl Methacrylate And Fluoro-Polyacrylate For Alkaline Direct Methanol Fuel Cells,
2011
College Chemistry & Chemical Engineering,Xiamen University,Xiamen 361005,Fujian,China;
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 …
A Titanium-Supported Nanoporous Pd Electrocatalyst For Methanol Oxidation,
2011
School of Chemistry and Chemical Engineering,Hunan University of Science and Technology,Xiangtan 411201,Hunan,China;
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,
2011
Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry & Materials Science,Northwest University,Xi'an 710069,China;
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,
2011
Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;
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 LiMxMn2-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.
Electrooxidation Of Methanol On Multilayer Films Of Polypyrrole-Platinum Electrode,
2011
Department of Chemistry,Shenyang Normal University,Shenyang 110034,China;
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,
2011
State Key laboratory of Gansu Advanced Non-ferrous Metal Materials,Lanzhou Univercity of Technology,Lanzhou 730050,China;
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.
