Materials Science and Engineering Commons^™

Effect Of Flame Retardant On Electrochemical Performances Of Lithium Ion Battery With Lini0.4Co0.2Mn0.4O2 As A Positive Electrode Material, Yan-Zhuo Lv, Yong-Xian Ge, Zhen-Bo Wang, Ke Ke

Journal of Electrochemistry

The effect of flame retardant on the electrochemical performances of lithium ion battery by using LiNi_0.4Co_0.2Mn_0.4O₂ as a positive material was studied by measuring the first charge-discharge, cycling, circulation, and AC impedance curves. The experimental data indicated that the discharge capacity of the battery decreased, while the charge transfer resistance and the lithium ion diffusion resistance increased with the increases in the concentrations of the flame retardant in the electrolyte solutions. Furthermore, the stability of the battery at small discharge ratios and the cyclic performance were also improved by the addition of flame …

Electricity Generation Of Microbial Fuel Cell Using Stainless Steel Mesh As Cathode, Hong-Yan Dai, Hui-Min Yang, Xian Liu, Xuan Jian, Xiu-Li Song, Zhen-Hai Liang

Journal of Electrochemistry

In the present work, a dual-chamber microbial fuel cell (MFC) was constructed with aeration tank sludge as an inoculum, carbon felt as an anode and stainless steel mesh without any modification as a cathode. The influence of the cathode size was investigated in terms of voltage output, power generation and electrochemical impedance. The long-term durability of the stainless steel mesh cathode was also evaluated. Results showed that the stainless steel mesh exhibited satisfactory long-term durability as MFC cathode. When the stainless steel mesh size was 2 × 2 cm², the maximum output voltage, power density, the internal resistance …

Fabrication Of Riboflavin Electrochemical Sensor Based On Au Nanoparticles/Polydopamine/Carbon Nanotubes Modified Glassy Carbon Electrode, Hua-Ping Peng, Mei-Ling Yu, Xin Liu, Pan Liu, Wei Chen, Ai-Lin Liu, Xin-Hua Lin

Journal of Electrochemistry

A novel electrochemical platform for the high sensitivity detection of riboflavin was constructed by Au nanoparticles/polydopamine/carbon nanotubes (Au-PDA-MWCNTs) nanocomposite modified glassy carbon electrode. The Au-PDA-MWCNTs nanocomposite was synthesized by in situ reduction method. The characteristics of the as-prepared Au-PDA-MWCNTs nanocomposite modified electrodes were investigated by using UV-Vis spectroscopy, scanning electron microscopy (SEM) and electrochemical methods. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to study the electrochemical behavior of riboflavin (RF) at Au-PDA-MWCNTs nanocomposite modified electrodes. The results demonstrated that the present electrochemical sensor exhibited a wide linear range from 5×10^-9 mol•L^-1to 1×10^-5 mol•L …

Electrochemical Detection Of Hydrogen Peroxide At Aunps Modified Electrode Using P-Hydroxyphenylboronic Acid As A Precursor, Chun-Yan Wang, Xiao-Qiu Liu, Ying-Xin Qi

Journal of Electrochemistry

We developed a new method for electrochemical detection of hydrogen peroxide (H₂O₂) based on boronate oxidation of p-hydroxyphenylboronic acid. This method using p-aminophenol which is produced from the reaction of H₂O₂ and p-aminophenylboronic acid as a well electrochemical probe, combined with a gold nanoparticles (AuNPs) modified electrode for an indirect detection of H₂O₂. Because of the large surface area and enhanced electrocatalytic behavior by the AuNPs modified electrode, the detection sensitivity was improved. The method could detect H₂O₂ in the concentration range of 1 ~ 100 …

Electrochemical Determination Of Hg(Ii) At Gold Nanoparticles@Carbonaceous Microspheres Modified Electrode, Tian-Yu Qiu, Ming-Chun Wang, Xian-Feng Du, Tian-Jia Jiang, Xing-Jiu Huang

Journal of Electrochemistry

The gold nanoparticles@carbonaceous microspheres (Au@CMSs) and  Au@CMSs modified glassy carbon electrode (GCE) were prepared. The Au@CMSs modified  GCE was further examined for possible sensitive detection of mercury ions (Hg(II)) in an aqueous solution by square wave anodic stripping voltammetry (SWASV). The excellent performance was found in the stripping analysis of Hg(II) in 0.1 mol•L^-1 NaAc-HAc(pH=5.0) with a sensitivity of 25.863 A•(mol•L^-1)^-1 and a detection limit of 3.69×10^-8 mol•L^-1 based on the 3σ method.

The Study On Comparison Of Electrochemical Performance In Microbial Fuel Cell With Glucose And Sodium Acetate Acting As Substrates, Lei Fan, Yu Zhao, Ting Li, Qin-Bo Yuan, En-Zhi Wang, Xiao-Bin Wang, Jun-Wen Wang

Journal of Electrochemistry

By inoculating aerobic sludge and anaerobic sludge from the sewage treatment plant, two sets of dual-chamber microbial fuel cells (MFCs) were built with either glucose or sodium acetate acting as a substrate. Accordingly, the electrochemical performances of MFCs were explored with the concentration of the substrates being 0.0335 mol⋅L^-1. The results of the comparative study in glucose system and sodium acetate system showed that the impedance values of anodic half cell were 222 Ω for glucose and 213.67 Ω for sodium acetate, implying no significant effect on the internal resistance in battery with the different substrates. The exchange …

Investigation Of Polyaniline And Its Composites As Interlayers In Organic Solar Cells, Omar Abdulrazzaq Al-Azzawi

Theses and Dissertations

Significant attention has been given during the last few years to overcoming technological and material barriers to the development of organic photovoltaic devices (OPVs) with cost efficiency comparable to that of inorganic photovoltaics (PVs). If OPVs are to become commercially viable, major improvements are necessary. In this work, polyaniline (PANI) protonated with various levels of camphorsulfonic acid (CSA) and dissolved in m-cresol has been used as a hole-transport layer (HTL) in organic bulk-heterojunction solar cells. Polyaniline was first synthesized using oxidative polymerization based on the MacDiarmid method. The polymerization parameters, such as polymerization temperature and polymerization pH control agent, were …

One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes, Hoang Anh Tran

Dissertations and Theses

The key challenge for a nanomaterial based sensor is how to synthesize in bulk quantity and fabricate an actual device with insightful understanding of operational mechanisms during performance. I report here effective, controllable methods that exploit the concepts of the "green approach" to synthesize two different one-dimensional nanostructures, including tin oxide nanowires and carbon nanotubes. The syntheses are followed by product characterization and sensing device fabrications as well as sensor performance understanding at the molecular level. Sensor-analyte response and recovery kinetics are also presented.

The first part of the thesis describes bulk-scale synthesis and characterization of tin oxide nanowires by …

Structure Functions, Scaling Exponents And Intermittency In The Wake Of A Wind Turbine Array, Naseem Ali, Aleksandr Sergeyevich Aseyev, Raúl Bayoán Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Hot-wire measurements obtained in a 3 × 3 wind turbine array boundary layer are utilized to analyze high order structure functions, intermittency effects as well as the probability density functions of velocity increments at different scales within the energy cascade. The intermittency exponent is found to be greater in the far-wake region in comparison with the near-wake. At hub height, the intermittency exponent is found to be null. Extended self-similarity scaling exponents of the second, fourth, and fifth order structure functions remain relatively constant as a function of height in the far-wake; whereas in the near-wake, these are highly affected …

Graphene Oxide Quantum Dots Covalently Functionalized Pvdf Membrane With Significantly-Enhanced Bactericidal And Antibiofouling Performances, Zhiping Zeng, Dingshan Yu, Ziming He, Jing Liu, Fang-Xing Xiao, Yan Zhang, Rong Wang, Dibakar Bhattacharyya, Timothy Thatt Yang Tan

Chemical and Materials Engineering Faculty Publications

Covalent bonding of graphene oxide quantum dots (GOQDs) onto amino modified polyvinylidene fluoride (PVDF) membrane has generated a new type of nano-carbon functionalized membrane with significantly enhanced antibacterial and antibiofouling properties. A continuous filtration test using E. coli containing feedwater shows that the relative flux drop over GOQDs modified PVDF is 23%, which is significantly lower than those over pristine PVDF (86%) and GO-sheet modified PVDF (62%) after 10 h of filtration. The presence of GOQD coating layer effectively inactivates E. coli and S. aureus cells, and prevents the biofilm formation on the membrane surface, producing excellent antimicrobial activity and …

Strain Effects On The Work Function Of An Organic Semiconductor, Yanfei Wu, Annabel R. Chew, Geoffrey A. Rojas, Gjergji Sini, Greg Haugstad, Alex Belianinov, Sergei V. Kalinin, Hong Li, Chad Risko, Jean-Luc Brédas, Alberto Salleo, C. Daniel Frisbie

Chemistry Faculty Publications

Establishing fundamental relationships between strain and work function (WF) in organic semiconductors is important not only for understanding electrical properties of organic thin films, which are subject to both intrinsic and extrinsic strains, but also for developing flexible electronic devices. Here we investigate tensile and compressive strain effects on the WF of rubrene single crystals. Mechanical strain induced by thermal expansion mismatch between the substrate and rubrene is quantified by X-ray diffraction. The corresponding WF change is measured by scanning Kelvin probe microscopy. The WF of rubrene increases (decreases) significantly with in-plane tensile (compressive) strain, which agrees qualitatively with density …

Daylighting And Thermo-Electrical Performance Of An Autonomous Suspended Particle Device Evacuated Glazing, Aritra Ghosh

Doctoral

Suspended particle device (SPD) glazing is an AC powered switchable glazing. PV powered SPD evacuated (vacuum) glazing was proposed with the potential of reducing the heating demand, cooling demand and artificial lighting demand of a building. To achieve an autonomous SPD vacuum glazing, semi empirical simulation and outdoor characterisation was explored in this thesis. Transmission of SPD glazing (area 0.058 m2) varied from 5% when opaque to 55% when transparent in the presence of 110 V, 0.07 W AC supply was characterised in outdoor test cell in Dublin. The SPD glazing has variable spectral transmission in the presence of variable …

Water Condensation And Protein Adsorption On Hybrid Superhydrophobic-Hydrophilic Surfaces, Bikash Mondal

Dissertations, Theses, and Capstone Projects

This thesis describes the study of protein adsorption and water condensation on hybrid superhydrophobic-hydrophilic surfaces for various technological applications such as diagnostics, artificial organs and medical devices, water collection, and heat transfer.

In the chapter 1, a general introduction to wetting theories, superhydrophobic surface, and hybrid surfaces is given. In chapter 2, design and fabrication of a hybrid superhydrophobic surface for studying dropwise condensation and heat transfer is discussed. Effect of surface chemistry and wettability on protein adsorption is discussed in the chapter 3. Finally, in chapter 4, the protein adsorption study on hybrid superhydrophobic surfaces made by 3D-printing and …

Erratum: "Composition- And Pressure-Induced Ferroelectric To Antiferroelectric Phase Transitions In Sm-Doped Bifeo₃ System" [Appl. Phys. Lett. 106, 012903 (2015)], Fei Xue, Linyun Liang, Yijia Gu, Ichiro Takeuchi, Sergei V. Kalinin, Long-Qing Chen

Materials Science and Engineering Faculty Research & Creative Works

In the acknowledgement of the original article, the Award No. DMR-0820404 should be replaced by DMR-1420620.

Erratum: Orientations Of Low-Energy Domain Walls In Perovskites With Oxygen Octahedral Tilts (Physical Review B - Condensed Matter And Materials Physics (2014) 90 (220101)), Fei Xue, Yijia Gu, Linyun Liang, Yi Wang, Long-Qing Chen

Materials Science and Engineering Faculty Research & Creative Works

In the Acknowledgment of the original article, the Award No. DMR-0820404 should be replaced by DMR-1420620.

Zncdmgse As A Materials Platform For Advanced Photonic Devices: Broadband Quantum Cascade Detectors And Green Semiconductor Disk Lasers, Joel De Jesus

Dissertations, Theses, and Capstone Projects

The ZnCdMgSe family of II-VI materials has unique and promising characteristics that may be useful in practical applications. For example they can be grown lattice matched to InP substrates with lattice matched bandgaps that span from 2.1 to 3.5 eV, they can be successfully doped n-type, have a large conduction band offset (CBO) with no intervalley scattering present when strained, they have lower average phonon energies, and the InP lattice constant lies in the middle of the ZnSe and CdSe binaries compounds giving room to experiment with tensile and compressive stress. However they have not been studied in detail for …

Experimental And Theoretical Evaluation Of In-Depth Damage Distribution In Sawn Silicon Wafers, Srinivasamurthy Devayajanam

Dissertations

As-sawn silicon wafers have surface damage that needs to be removed before any further processing into solar cells. This damage distribution can vary with cutting parameters such as wire size, slurry particle/diamond grit size, and wire usage. To date, there is no simple way to measure the degree of damage, damage depth, and damage distribution. But, this information is needed by the wafer manufacturers as well as solar cell manufacturers.

A technique based on sequential etching of silicon wafers and minority carrier lifetime (τ_eff) measurements is used to determine damage depth. In this technique, samples are sequentially etched …

Thermoelectric Properties Of Silicon-Germanium Alloys, Aniket Annasaheb Maske

Theses

Direct energy conversion from thermal to electrical energy, based on thermoelectric effects, is attractive for potential applications in waste heat recovery and environmentally friendly refrigeration. The energy conversion efficiency of thermoelectric devices is related to the thermoelectric figure of merit ZT, which is proportional to the electrical conductivity, the square of the Seebeck coefficient, and the inverse of the thermal conductivity. Currently, the low ZT values of available materials restrict the large scale applications of this technology. Recently, however, significant enhancements in ZT have been reported in nanostructured materials such as super-lattices mainly due to their low thermal conductivities. According …

Understanding Bulk Behavior Of Particulate Materials From Particle Scale Simulations, Xiaoliang Deng

Dissertations

Particulate materials play an increasingly significant role in various industries, such as pharmaceutical manufacturing, food, mining, and civil engineering. The objective of this research is to better understand bulk behaviors of particulate materials from particle scale simulations.

Packing properties of assembly of particles are investigated first, focusing on the effects of particle size, surface energy, and aspect ratio on the coordination number, porosity, and packing structures. The simulation results show that particle sizes, surface energy, and aspect ratio all influence the porosity of packing to various degrees. The heterogeneous force networks within particle assembly under external compressive loading are investigated …

Development Of Pvdf Membrane Nanocomposites Via Various Functionalization Approaches For Environmental Applications, Douglas M. Davenport, Minghui Gui, Lindell E. Ormsbee, Dibakar Bhattacharyya

Chemical and Materials Engineering Faculty Publications

Membranes are finding wide applications in various fields spanning biological, water, and energy areas. Synthesis of membranes to provide tunable flux, metal sorption, and catalysis has been done through pore functionalization of microfiltration (MF) type membranes with responsive behavior. This methodology provides an opportunity to improve synthetic membrane performance via polymer fabrication and surface modification. By optimizing the polymer coagulation conditions in phase inversion fabrication, spongy polyvinylidene fluoride (PVDF) membranes with high porosity and large internal pore volume were created in lab and full scale. This robust membrane shows a promising mechanical strength as well as high capacity for loading …

Free And Open-Source Control Software For 3-D Motion And Processing, Bas Wijnen, G. C. Anzalone, Amberlee S. Haselhuhn, Paul G. Sanders, Joshua M. Pearce

Department of Materials Science and Engineering Publications

RepRap 3-D printers and their derivatives using conventional firmware are limited by: 1) requiring technical knowledge, 2) poor resilience with unreliable hardware, and 3) poor integration in complicated systems. In this paper, a new control system called Franklin, for CNC machines in general and 3-D printers specifically, is presented that enables web-based three dimensional control of additive, subtractive and analytical tools from any Internet connected device. Franklin can be set up and controlled entirely from a web interface; it uses a custom protocol which allows it to continue printing when the connection is temporarily lost, and allows communication with scripts.

Influence Of Oxygen Concentration On The Performance Of Ultra-Thin Rf Magnetron Sputter Deposited Indium Tin Oxide Films As A Top Electrode For Photovoltaic Devices, Jephias Gwamuri, Murugesan Marikkannan, J. Mayandi, Patrick Bowen, Joshua M. Pearce

Department of Materials Science and Engineering Publications

The opportunity for substantial efficiency enhancements of thin film hydrogenated amorphous silicon (a-Si:H) solar photovoltaic (PV) cells using plasmonic absorbers requires ultra-thin transparent conducting oxide top electrodes with low resistivity and high transmittances in the visible range of the electromagnetic spectrum. Fabricating ultra-thin indium tin oxide (ITO) films (sub-50 nm) using conventional methods has presented a number of challenges; however, a novel method involving chemical shaving of thicker (greater than 80 nm) RF sputter deposited high-quality ITO films has been demonstrated. This study investigates the effect of oxygen concentration on the etch rates of RF sputter deposited ITO films to …

Late Morning Concurrent Sessions: Innovations In Aviation Technologies: Presentation: Relative Material Loss: A Methodology For Assessing Island Airport Steel Marine Bulkheads, Robert Ernsting, Constantine M. Koursaris

Aviation / Aeronautics / Aerospace International Research Conference

A July 2015 report from the Airports Council International – North America (ACI-NA) states “U.S. airports are long overdue for [a] major structural improvement projects. Most U.S. airports are aging, … and because of budgetary restrictions, they’re not aging well.”(Garcia and Clampet, 2015). The average US age is 40 years old with the youngest (Denver International) recently turning 20 years old. As airports continue to age, airport commissioners will struggle to find creative ways to either fund airport replacements or extend the service life of existing airport facilities (commonly referred to as service life extension projects or SLEP). Due to …

High-Efficiency Solar-Powered 3-D Printers For Sustainable Development, Jephias Gwamuri, Dhiogo Franco, Khalid Khan, Lucia Gauchia, Joshua M. Pearce

Michigan Tech Publications, Part 1

The release of the open source 3-D printer known as the RepRap (a self-Replicating Rapid prototyper) resulted in the potential for distributed manufacturing of products for significantly lower costs than conventional manufacturing. This development, coupled with open source-appropriate technology (OSAT), has enabled the opportunity for 3-D printers to be used for sustainable development. In this context, OSAT provides the opportunity to modify and improve the physical designs of their printers and desired digitally-shared objects. However, these 3-D printers require electricity while more than a billion people still lack electricity. To enable the utilization of RepRaps in off-grid communities, solar photovoltaic …

Mechanical Self-Assembly Of A Strain-Engineered Flexible Layer: Wrinkling, Rolling, And Twisting, Zi Chen, Gaoshan Huang, Ian Trase, Xiaomin Han, Yongfeng Mei

Dartmouth Scholarship

Self-shaping of curved structures, especially those involving flexible thin layers, is attracting increasing attention because of their broad potential applications in, e.g., nanoelectromechanical andmicroelectromechanical systems, sensors, artificial skins, stretchable electronics, robotics, and drug delivery. Here, we provide an overview of recent experimental, theoretical, and computational studies on the mechanical self-assembly of strain-engineered thin layers, with an emphasis on systems in which the competition between bending and stretching energy gives rise to a variety of deformations, such as wrinkling, rolling, and twisting. We address the principle of mechanical instabilities, which is often manifested in wrinkling or multistability of strain-engineered thin layers. …

Reversible Plastic Events During Oscillatory Deformation Of Amorphous Solids, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The effect of oscillatory shear strain on nonaffine rearrangements of individual particles in a three-dimensional binary glass is investigated using molecular dynamics simulations. The amorphous material is represented by the Kob-Andersen mixture at the temperature well below the glass transition. We find that during periodic shear deformation of the material, some particles undergo reversible nonaffine displacements with amplitudes that are approximately power-law distributed. Our simulations show that particles with large amplitudes of nonaffine displacement exhibit a collective behavior; namely, they tend to aggregate into relatively compact clusters that become comparable with the system size near the yield strain. Along with …

System And Method For Identifying Electrical Properties Of Integrate Circuits, Mary Y. Lanzerotti

AFIT Patents

A new method for displaying electrical properties for integrated circuit (IC) layout designs provides for improved human visualization of those properties and comparison of as designed layout design parameters to as specified layout design parameters and to as manufactured layout parameters. The method starts with a circuitry as designed layout in a first digital format, extracts values for electrical properties from that circuitry as designed layout then annotates those values back into the first digital format. The annotated circuitry as designed layout is then converted from the first digital format to a second digital format that can be converted to …

Paper Core Feeder System, Sergio Flores Velez

All Undergraduate Projects

Paragon Films has always strived to increase productivity and decrease waist within their company. The plant located in Union Gap, Washington currently has two production lines operating 24/7 managed by 2 to 3 people. The heavy line produces 5000 to 10000 revolutions per roll. This production line has a three part system that automatically feeds the paper cores to the spool shafts to roll the films. Therefore, the employees during that shift do not have to worry about filling up the bin very often. On the other hand, the second production line, which produces the hand films, does not have …

Conversion Casting: Adapter Hub, Joseph M. Coup

All Undergraduate Projects

The concept of conversion casting makes manufacturing major components much more efficient with regards to time and cost. The conversion cast of the adapter hub used in the Victair Mistifier is a major component that requires 8 hours to machine. The existing hub starts from steel stock and then that block of steel is placed into a CNC machine and coded in to create the adapter hub. The manufacturing method changes to a casting for the adapter hub will create a replicated part that requires 1.5 hours of post machining. The intricate design makes a conversion to casting more effective …

State-Of-The-Art Review Of Cathodic Protection For Reinforced Concrete Structures, Aimee Byrne, Niall Holmes, Brian Norton

Articles

Cathodic protection (CP) limits the corrosion of a metal surface by making it the cathode of an electrochemical cell. This can be achieved either by using a more active sacrificial anode to create a driving current, or by using inert anodes and impressing a current onto the cathode surface using an external direct current (DC) source. Impressed current cathodic protection (ICCP) is preferred where widespread protection is required, particularly in reinforced concrete structures. ICCP needs a constant DC power supply that is usually provided through a grid connection or independent generators. This paper presents the currently available CP systems for …