Engineering Science and Materials Commons^™

Lithium Polysulfide Battery With Improved Capacity And Cycle Performance Using Carbon Black Coated Free-Standing Carbon Cloth, Zhen Wei

Electronic Theses and Dissertations

Lithium ion batteries (LIBs) have been used in various applications such as portable electronics, grid storages, and electric vehicles (EVs). Despite its commercial success, further advancement of the battery is necessary to satisfy the increasing demands for low-cost and high- performance energy storage devices as LIB is reaching its theoretical limits. Lithium sulfur battery (LSB) is one of the promising candidates for the next generation energy storage technologies. LSB uses sulfur cathode which is a low-cost and earth abundant material with an extremely high theoretical capacity of 2600 Wh kg-1. Although there have been numerous researches aiming to establish the …

Development Of S-Nitroso-N-Acetylpenicillamine (Snap) Impregnated Medical Grade Polyvinyl Chloride For Antimicrobial Medical Device Interfaces, Corbin Feit

Electronic Theses and Dissertations

In the clinical setting, polyvinyl chloride (PVC) accounts for 25% of all polymers used in medical device applications. However, medical devices fabricated with PVC, such as endotracheal tubes, extracorporeal circuits (ECCs), or intravenous catheters suffer from thrombosis and infection. Mortality associated with hospital associated infections (HAIs) exceed 100,000 deaths each year. One method to overcome these challenges is to develop bioactive polymers with nitric oxide (NO) release. Nitric oxide exhibits many physiological roles including, antibacterial, antithrombic, anti-inflammatory activity. In this study, Tygon® PVC tubing was impregnated with a NO donor molecule, S-nitroso-N-acetylpenicillamine (SNAP), via a simple solvent-swelling-impregnation method, where polymer …

Development Of In Vitro Point Of Care Diagnostics (Ivpcd) Based On Aptamers Integrated Biosensors, Nileshi Saraf

Electronic Theses and Dissertations

The global market for the medical diagnostic industry is worth 25 billion dollars in the United States and is expected to grow exponentially each year. Presently available methods for biodetection, such as immunoassays, chemiluminescence and fluorescent based assays are expensive, time consuming and require skilled labor with high-end instruments. Therefore, development of novel, passive colorimetric sensors and diagnostic technologies for detection and surveillance is of utmost importance especially in resource constrained communities. The present work focusses on developing novel and advanced in vitro biodiagnostic tools based on aptamer integrated biosensors for an early detection of specific viral proteins or small …

Interfacial Behavior In Polymer Derived Ceramics And Salt Water Purification Via 2d Mos2, Hao Li

Electronic Theses and Dissertations

In the present dissertation, the behavior of the internal potential barrier in a polymer-derived amorphous SiAlCN ceramic was studied by measuring its complex impedance spectra at various dc bias as well as different testing and annealing temperatures. The complex impedance spectra of the polymer-derived a-SiAlCN were measured under various dc bias voltages in a temperature range between 50 and 150°C, as well as different annealing temperatures (1100-1400 °C). All spectra, regardless of temperature and bias, consist of two semi-circular arcs, corresponding to the free-carbon phase and the interface, respectively. The impedance of the free-carbon phase is independent of the bias, …

Resistance To Helium Bubble Formation In Amorphous Sioc/Crystalline Fe Nanocomposite, Qing Su, Tianyao Wang, Jonathan Gigax, Lin Shao, Michael Nastasi

Department of Mechanical and Materials Engineering: Faculty Publications

The management of radiation defects and insoluble He atoms represent key challenges for structural materials in existing fission reactors and advanced reactor systems. To examine how crystalline/amorphous interface, together with the amorphous constituents affects radiation tolerance and He management, we studied helium bubble formation in helium ion implanted amorphous silicon oxycarbide (SiOC) and crystalline Fe composites by transmission electron microscopy (TEM). The SiOC/Fe composites were grown via magnetron sputtering with controlled length scale on a surface oxidized Si (100) substrate. These composites were subjected to 50 keV He+ implantation with ion doses chosen to produce a 5 at% peak He …

Fast Growth Of Thin Mapbi3 Crystal Wafers On Aqueous Solution Surface For Efficient Lateral-Structure Perovskite Solar Cells, Ye Liu, Qingfeng Dong, Yanjun Fang, Yuze Lin, Yehao Deng, Jinsong Huang

Department of Mechanical and Materials Engineering: Faculty Publications

Solar-grade single or multiple crystalline wafers are needed in large quantities in the solar cell industry, and are generally formed by a top-down process from crystal ingots, which causes a significant waste of materials and energy during slicing, polishing, and other processing. Here, a bottom-up technique that allows the growth of wafer-size hybrid perovskite multiple crystals directly from aqueous solution is reported. Single-crystalline hybrid perovskite wafers with centimeter size are grown at the top surface of a perovskite precursor solution. As well as saving raw materials, this method provides unprecedented advantages such as easily tunable thickness and rapid growth of …

Machine Vision Integrated Three-Dimensional Printing System, Chaiwuth Sithiwichankit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Three-dimensional printing has been a widespread solution of fabricating geometrical customized products. Any 3D printed product is normally fabricated at a position defined with respect to the coordinate system of the corresponding 3D printer. So, the 3D printing cannot be conveniently implemented in some fabricating applications in which fabricating positions are commonly constrained to some physical references, e.g., architecture construction, surface restoration, food decoration, etc. This research aimed to integrate the 3D printing with machine vision, which is vastly used for guiding robotic systems to operate at desirable positions constrained to physical objects. Hence, the 3D printing can be conveniently …

Geothermal Resource Assessment Of Mississippi, Adam Blake Goodwin

Electronic Theses and Dissertations

Geothermal energy is exploited through the process of using hot water or steam extracted from reservoirs of geothermal heat in Earth's crust which is derived from the upward convection and conduction of heat from Earth’s mantle and core. This energy can be harnessed to power geothermal heat pumps, heat water, or to generate electricity. Previous geothermal assessments of Mississippi have been locally focused, either in the southern Mississippi River flood plains or in eastern north central Mississippi at an active lignite coal mine. The focus of this project was to calculate and map heat flow estimates within the entire state …

A Numerical Study Of Granular Dam-Break Flows, Nuttita Pophet

Electronic Theses and Dissertations

Granular flows are mass movements of mixtures of solid particles and interstitial fluid. Examples include landslides, debris flows and tailings dam-break flows. These types of flows are often catastrophic events, and cover a wide range of phenomena of interest to both scientists and engineers. The mechanical properties of granular materials and the hydraulic behavior of the flows originate from solid and fluid phases, their distribution and interaction. Understanding the behavior of these types of flows and developing reliable predictive models are important.

Wearable Devices For Single Cell Sensing And Transfection, Lingqian Chang, Yu-Chieh Wang, Faheem Ershad, Ruiguo Yang, Cunjiang Yu, Yubo Fan

Department of Mechanical and Materials Engineering: Faculty Publications

Transdermal drug delivery systems have been successful for decades. Now these devices can be further scaled down, and their applications have been extended to wide selections of cargo, ranging from natural molecules (e.g., insulin and glucose) to bioengineered molecules (e.g., nanoparticles and vaccines). Some emerging nanopatches show promise for precise single-cell gene transfection in vivo and have advantages over conventional tools in terms of delivery efficiency, safety, and controllability of delivered dose. In this review, we discuss recent technical advances in wearable micro/nano devices with unique capabilities or potential for single-cell biosensing and transfection in the skin or other organs, …

Segregation Of Mo Atoms Into Stacking Faults In Crfeconimo Alloy, Kaisheng Ming, Xiaofang Bi, Jian Wang

Department of Mechanical and Materials Engineering: Faculty Publications

Solute segregation at dislocations can impede the motion of dislocations, strengthening materials. Here, we study the formation and role of solute segregation at dislocations in CrFeCoNiMo high-entropy alloys (HEAs) by high-angle annular dark-field scanning transmission electron microscopy imaging and mechanical testing both deformed and annealed samples. Mo atoms exhibit pronounced segregation into the planar-extended core of dislocations, i.e. stacking faults, causing the increase in the yield strength while the loss of the ductility. This work suggests that mechanical properties of HEAs can be tailored by alloying additional elements that are in favor of segregation into dislocations.

Optimization Of Protein-Protein Interaction Measurements For Drug Discovery Using Afm Force Spectroscopy, Yongliang Yang, Bixi Zeng, Zhiyong Sun, Amir Monemianesfahani, Jing Hou, Nian-Dong Jiao, Lianqing Liu, Liangliang Chen, Marc D. Basson, Lixin Dong, Ruiguo Yang, Ning Xi

Department of Mechanical and Materials Engineering: Faculty Publications

Increasingly targeted in drug discovery, protein-protein interactions challenge current high throughput screening technologies in the pharmaceutical industry. Developing an effective and efficient method for screening small molecules or compounds is critical to accelerate the discovery of ligands for enzymes, receptors and other pharmaceutical targets. Here, we report developments of methods to increase the signal-to-noise ratio (SNR) for screening protein-protein interactions using atomic force microscopy (AFM) force spectroscopy. We have demonstrated the effectiveness of these developments on detecting the binding process between focal adhesion kinases (FAK) with protein kinase B (Akt1), which is a target for potential cancer drugs. These developments …

Local Control Robotic Surgical Devices And Related Methods, Eric Markvicka, Tom Frederick, Jack Mondry, Joe Bartels, Shane Michael Farritor

Department of Mechanical and Materials Engineering: Faculty Publications

The various robotic medical devices include robotic devices that are disposed within a body cavity and positioned using a support component disposed through an orifice or opening in the body cavity. Additional embodiments relate to devices having arms coupled to a device body wherein the device has a minimal profile such that the device can be easily inserted through smaller incisions in comparison to other devices without such a small profile. Further embodiments relate to methods of operating the above devices.

Medical Inflation, Attachment And Delivery Devices And Related Methods, Mark Rentschler, Shane Michael Farritor

Department of Mechanical and Materials Engineering: Faculty Publications

The various embodiments disclosed herein relate to procedural space maintenance devices, medical device positioning devices, and devices that provide both procedural space maintenance and device positioning. Further embodiments relate to medical device insertion and/or retraction devices.

Deformation Correlations And Machine Learning: Microstructural Inference And Crystal Plasticity Predictions, Michail Tzimas

Graduate Theses, Dissertations, and Problem Reports (ETD)

The present thesis makes a connection between spatially resolved strain correlations and material processing history. Such correlations can be used to infer and classify prior deformation history of a sample at various strain levels with the use of Machine Learning approaches. A simple and concrete example of uniaxially compressed crystalline thin films of various sizes, generated by two-dimensional discrete dislocation plasticity simulations is examined. At the nanoscale, thin films exhibit yield-strength size effects with noisy mechanical responses which create an interesting challenge for the application of Machine Learning techniques. Moreover, this thesis demonstrates the prediction of the average mechanical responses …

Preliminary Examination Of The Effects Of Time And Flexural Direction On An Anisotropic Geosynthetic Cementitious Composite Mat, James M. Proctor

Undergraduate Honors Theses

The significance of this research was to determine the effect the main fabric weave direction and cure time has on the maximum load of 0.34 inch anisotropic Geosynthetic Cementitious Composite Mat sample coupons. Two series of tests were run. The first used a three-point bend test on the material samples with varying cure times to determine the average maximum load associated with each. The second series of testing used followed ASTM D8030/D8030M - 16 for sample preparation and ASTM D8058 - 17 for testing to determine the flexural strength and modulus of elasticity of the test samples with and against …

Microstructure Evolution Of Chalcogenide Materials Via Molecular Dynamics, Sharmin Abdullah

Open Access Theses & Dissertations

The properties of a material are defined by its granular microstructure which is determined by its grain evolution and the types of grain boundaries present in the structure. For example, the performance of Cadmium Sulfide/Cadmium Telluride (CdS/CdTe) solar cells can be affected by the presence of grain boundaries which makes the study of grain structure evolution a very important part of solar cell performance optimization. Grain boundary mobilities are important properties in material science and engineering as they determine grain structures under given processing and operating conditions.

In this thesis, several computational tools were used to analyze the formation and …

Development And Characterization Of Polyethylene Terephthalate (Pet)-Cotton Natural Fiber-Reinforced Composites From Waste Materials, Israel Alejandro Carrete

Open Access Theses & Dissertations

Unprecedented levels of production and consumption have caused a rapid exhaustion of the Earth's virgin resources, which is coupled with a fast accumulation of contaminants in the form of solid waste, especially in landfills. Two significant landfill constituents come from textile waste and discarded plastic bottles. Since there is a finite amount of space that can be feasibly used for landfills, solutions that make use of these post-consumer products are imperative. This study presents one possible solution by using surface modifications of cotton fibers to produce a natural fiber-reinforced polymer composite (NFRPC) from post-consumer textile waste and polyethylene terephthalate (PET) …

Tailoring Physical Properties Of Shape Memory Polymers For Fdm-Type Additive Manufacturing, Paulina Aileen Quinonez

Open Access Theses & Dissertations

Shape memory polymers (SMPs) have found applicability in biomedical settings as well as other uses that can take advantage of objects that can change shape upon exposure to stimulus. Integrating polymers with shape memory characteristics into additive manufacturing technologies such as fused deposition modeling (FDMâ?¢) can increase the number of applications this manufacturing platform can be utilized. Currently, polyurethane and polylactic acid (PLA) are two FDMâ?¢-compatible materials that possess shape memory properties. On their own these materials do not have tunable shape memory properties, namely shape recovery and shape fixation. The work presented here entails the development and characterization of …

Nanoscale Spectroscopy In Energy And Catalytic Applications, Yi Ding

Electronic Theses and Dissertations

Emerging societal challenges such as the need for more sustainable energy and catalysis are requiring more sensitive and versatile measurements at the nanoscale. This is the case in the design and optimization of new materials for energy harvesting (solar cells) and energy storage devices (batteries and capacitors), or for the development of new catalysts for carbon sequestration or other reactions of interest. Hence, the ability to advance spectroscopy with nanoscale spatial resolution and high sensitivity holds great promises to meet the demands of deeper fundamental understanding to boost the development and deployment of nano-based devices for real applications. In this …

Synthesis, Design, And Evaluation Of The Fluorescent Detection Of Polychlorinated Biphenyls(Pcbs) In Aqueous System, Irfan Ahmad

Theses and Dissertations--Chemical and Materials Engineering

The exposure to halogenated persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), has been linked to numerous inflammatory diseases, including diabetes, cancer and lowered immune response. PCBs have low solubility in water, and they interact with other contaminants, making their detection quite challenging. While, there have been several attempts at improving the ease of detection and sensing of PCBs, gas chromatography-mass spectrometry (GC-MS) remains the gold standard. However, despite its ubiquitous use, GC-MS is a challenging technique that requires high skill and careful sample preparation, which are time-consuming and costly. As such, there is still a need to develop …

Theoretical And Experimental Study For Tailoring The Electromagnetic Properties Of Conductive Materials, Jeffrey Jennings

Electronic Theses and Dissertations

Induction in leaded, implanted medical devices exposed to radio frequency (RF) magnetic fields during magnetic resonance imaging (MRI) produce Joule heating in adjacent tissues causing various issues, including death. Given the importance of MRI as a diagnostic tool and the growth in leaded device-related treatments, identification of a solution ensuring their compatibility is of great interest. Electromagnetic (EM) surface property tailoring in lead materials to change their inductive response by adding functionally-graded, heterogeneous surface layers is a possible solution. However, non-uniform EM properties introduce two challenges: the added complexity of analyses and characterization of the graded region. This dissertation addresses …

Analysis Of Residual Stress And Damage Mechanisms Of Thermal Barrier Coatings Deposited Via Ps-Pvd And Eb-Pvd, Linda Rossmann

Electronic Theses and Dissertations

Thermal barrier coatings (TBCs) are critical to gas turbine engines, as they protect the components in the hot section from the extreme temperatures of operation. The current industry standard method of applying TBCs for turbine blades in jet engines is electron-beam physical vapor deposition (EB-PVD), which results in a columnar structure that is valued for its high degree of strain tolerance. An emerging deposition method is plasma-spray physical vapor deposition (PS-PVD), capable of producing a variety of customizable microstructures as well as non-line-of-sight deposition, which allows more complex geometries to be coated, or even multiple parts at once. The pseudo-columnar …

Technological Cooperation Network In Biotechnology Analysis Of Patents With Brazil As The Priority Country, Cristiano Goncalves Pereira, Rodrigo Ribeiro Da Silva, Joao Ricardo Lavoie, Geciane Silveira Porto

Engineering and Technology Management Faculty Publications and Presentations

Purpose – The establishment of partnerships between companies, government and universities aims to enhance innovation and the technological development of institutions. The biotechnology sector has grown in recent years mainly driven by its cooperative business model. Compared to other countries, this sector is slowly advancing in Brazil, with delays in science, technology and innovation, especially in the private sector. This paper aims to examine, through social network analysis, the collaborative networks between institutions that filed patents in biotechnology – medicinal preparations from plants – whose inventions had Brazil as the priority country. Design/methodology/approach – The study of technological cooperation using …

Fe Modeling Methodology For Load Analysis And Preliminary Sizing Of Aircraft Wing Structure, Jun Hwan Jang, Sang Ho Ahn

International Journal of Aviation, Aeronautics, and Aerospace

It is a critical part at the basic design phase of aircraft structural design to build a finite element model and it will have a direct impact on time and cost for airframe structure development. In addition, the objective of finite element model will be varied depending on each design review phase and the modelling methodology varied accordingly. In order to build an effective and economic finite element model, it is required to develop adequate level of modelling methodology based on each design phase and its objectives. Therefore, in this paper, the finite element modeling methodology was presented for internal …

Cmas/Volcanic Ash Infiltration Performance Of Yttria Rich-Zirconia Thermal Barrier Coatings Produced By Electron Beam Physical Vapor Deposition, Juan Jose Gomez Chavez

Open Access Theses & Dissertations

For many years the use of thermal barrier coatings (TBC) in gas turbine engines has allowed a significant increase in engine operating temperatures which are above the Ni-based super alloys' melting point. The base material for TBCs is the state of the art 7 wt % yttria stabilized zirconia (YSZ) which provides the thermal protection. Current industry demands for increased engine efficiency has pushed TBCs to the limits where significant technological constrains have been identified. One of the main ones represents the high temperature corrosion of the TBC material due to the ingestion of silicate based airborne particles commonly referred …

Fabrication And Characterization Of Nonlinear Optical Ceramics For Random Quasi-Phase-Matching, Xuan Chen

Electronic Theses and Dissertations

A number of technologies rely on the conversion of short laser pulses from one spectral domain to another. Efficient frequency conversion is currently obtained in ordered nonlinear optical materials and requires a periodic spatial modulation of their nonlinear coefficient which results in a narrow bandwidth. One can trade off efficiency for more spectral bandwidth by relaxing the strict phase-matching conditions and achieve nonlinear interaction in carefully engineered disordered crystalline aggregates, in a so-called random quasi-phase-matching (rQPM) process. In this dissertation, we examine appropriate fabrication pathways for (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT) and ZnSe transparent ceramics for applications in the mid-IR. The main challenge …

Exploration And Optimization Of Biomaterials And Cells Required For The Fabrication Of A "Cardiac Patch", Shweta Anil Kumar

Open Access Theses & Dissertations

Cardiac failure induced by myocardial infarction is believed to be one of the primary causes of morbidity and mortality all over the world. Affecting more than 26 million people worldwide, its prevalence has been observed to increase steadily. Myocardial infarction, which intitially begins as the occlusion of of a coronary artery, results in the death of millions of cardiomyocytes by obstructing blood flow to the serviced regions of the myocardium. The dead myocardium is replaced by a dense,collagenous scar which reduces the contractility of the heart, gradually leading to heart attacks. Most of the existing treatment therapies are palliative in …

A Method For Iron Determination During Copper Electrometallurgy And Its Application To The Calculation Of Current Efficiency, Daniel Pedro Cruz

Open Access Theses & Dissertations

With the objective of developing statistical models that describe iron kinetics under typical copper electrolytes as well as its effects on current efficiency and influence in cathodic and anodic behavior, a detailed electrochemical analysis is done in this work as a contribution to implement hydrometallurgical processes in the refining or winning process to produce high purity copper.

This Thesis evaluates the oxidation-reduction potential (ORP) of the Fe3+/Fe2+ couple in the H2SO4-Fe2(SO4)3-FeSO4-H2O and H2SO4-CuSO4-Fe2(SO4)3-FeSO4-H2O systems, with addition of different copper concentrations and temperatures up to 70°, typically employed in the industry. This study further validates and expands a thermodynamic expression developed …

Processing, Structure And Mechanical Behavior Of Advanced Engineering Steels, Bing Yu

Open Access Theses & Dissertations

The concept of low lattice misfit and high-density of nanoscale precipitates obtained through solution treatment was adopted to obtain ultrahigh strength maraging steel without compromising elongation. An "ultrahigh strength-high toughness" combination was successfully obtained in 19Ni3Mo1.5Ti maraging steel with ultimate strength of ~1858 MPa and static toughness of ~110 MJ·m-3. Maraging steel had extremely high density (2.3Ã?1024 m-3) of nanoscale precipitates with minimum lattice misfit of less than 1% at the solutionization temperature of 820 oC. Two kinds of nanoscale precipitates, namely, η-Ni3(Ti,Mo) and B2-Ni(Mo,Fe) contributed to ultrahigh strength. The size of nanoscale precipitates governed the movement of dislocations, cutting …