Materials Science and Engineering Commons^™

Pseudomorphic Growth Of Inas On Misoriented Gaas For Extending Quantum Cascade Laser Wavelength, Gregory Edward Triplett, Charles Meyer, Emily Cheng, Justin Grayer, David Mueller, Denzil Roberts, Samuel Graham

Electrical and Computer Engineering Publications

The authors have studied the impact of epilayer strain on the deposition of InAs/GaAs on (100) and (111)B with 2 degrees offset toward 2-1-1 surfaces. Consequences of a 7% lattice mismatch between these orientations in the form of three-dimensional growth are less apparent for (111)B with 2 degrees offset toward 2-1-1 surfaces compared to (100). By exploring a range of molecular beam epitaxy process parameters for InAs/GaAs growth and utilizing scanning electron microscopy, atomic force microscopy, and Raman spectroscopy to evaluate the quality of these strained layers, the authors develop empirical models that describe the influence of the process conditions …

Investigation Of Astm E 238 Bearing Pin Properties For Various Aerospace Alloys, Trevor J. Lee

Master's Theses

Aircraft are often designed with numbers determined by testing in a lab, rather than by repeatedly building prototypes. These lab tests conform to testing specifications so that the numbers can be compared between manufacturers, suppliers, and lab technicians. One such specification is ASTM specification E238 – 84(08), and it is used to determine important properties of a bearing pin joint like hinges, bolt holes, and rivet joints. The properties determined from this fastener-through-plate method are bearing strength, bearing yield strength, and bearing stiffness.

Adhering to the methods outlined in ASTM E238, a study was performed, looking at the effects that …

Transient And Quasi-Steady Thermal Behaviour Of A Building Envelope Due To Retrofitted Cavity Wall And Ceiling Insulation, Aimee Byrne, Gerard Byrne, Anna Davies, Anthony Robinson

Articles

Accurate understanding of the thermal behaviour of building components is essential for predicting heat-ing or cooling needs and facilitates the implementation of more successful energy saving strategies and retrofits. This paper focuses on a specific measure commonly introduced through the residential energy efficiency retrofit programmes in Ireland–insulation. Traditionally, assessments of the performance of building envelopes have been based on assumed thermal resistances of the materials involved, labora-tory tests and computer modelling. The aim of the present work is to investigate the in situ thermal behaviour of a case study building and its components under transient and quasi-steady environmental conditions, comparing …

Structure And Properties Of Cocoons And Silk Fibers Produced By Attacus Atlas, Narendra Reddy, Yi Zhao, Yiqi Yang

Department of Textiles, Merchandising and Fashion Design: Faculty Publications

Silk fibers in the three layers of Attacus atlas (A. atlas) cocoons have morphological structure and tensile properties similar to that of Bombyx mori silk. Attempts are being made to produce silk for commercial applications from cocoons of relatively unknown wild insects due to the unique properties of the fibers and as a source of income and employment. In this research, A. atlas cocoons were used to study the chemical composition, morphology, physical structure and tensile properties of the silk fibers in the cocoons and ability of the fibers to support the attachment and proliferation of mouse fibroblast cells. It …

Molecular Crystallization Directed By Nanoparticles And Nanopatterns, Li Li

Wayne State University Dissertations

This dissertation focuses on nanoparticle/nanopattern-induced molecular self-assembly and crystallization. We propose a universal strategy to synthesize organic/inorganic hybrid nanostructures using inorganic nanoparticles and nanoparticle arrays to induce organic crystalline compound nucleation and crystallization. The nanoconfinement effect will be addressed to study molecular crystallization by changing nanoparticle size, curvature and separation distance. Atomic force microscopy (AFM) is the main characterization tool to investigate the topography of the hybrid nanostructures and the nucleation and crystallization process. This work will contribute to the understanding of seed mediated nucleation and crystallization, molecular ordering under nanoconfinement and hybrid nanomaterials.

Micromechanical Analysis Of Nanoparticle-Reinforced Dental Composites, Yi Hua, Linxia Gu, Hidehiko Watanabe

Department of Mechanical and Materials Engineering: Faculty Publications

The mechanical behavior of TiO₂ nanoparticle-reinforced resin-based dental composites was characterized in this work using a three-dimensional nanoscale representative volume element. The impacts of nanoparticle volume fraction, aspect ratio, stiffness, and interphase zone between the resin matrix and nanoparticle on the bulk properties of the composite were characterized. Results clearly demonstrated the mechanical advantage of nanocomposites in comparison to microfiber-reinforced composites. The bulk response of the nanocomposite could be further enhanced with the increased nanoparticle volume fraction, or aspect ratio, while the influence of nanoparticle stiffness was minimal. The effective Young’s modulus and yield strength of the composite was …

Bioreducible Polymer Nanosystems For Gene Delivery, Yi Zou

Wayne State University Dissertations

This dissertation describes the research of bioreducible polymers for gene delivery. A series of bioreducible poly(amido amine)s (PAAs) were synthesized. They complex with DNA forming polyplex nanoparticles and layer-by-layer (LbL) thin films as gene delivery vectors. Atomic force microscope (AFM), especially in situ real time AFM, provides a microscopic view of DNA release dynamics. It is shown that the depolymerization of bioreducible polymer triggers DNA release via disulfide-thiol exchange reaction. The AFM images revealed a three-stage pathway beginning with a morphological change from metastable nanostructures into the more favorable toroid structure. Then toroids interact with each other by aggregation and …

Green Diesel Production Via Catalytic Hydrogenation/Decarboxylation Of Triglycerides And Fatty Acids Of Vegetable Oil And Brown Grease, Elvan Sari

Wayne State University Dissertations

Increase in the petroleum prices, projected increases in the world’s energy demand and environmental awareness have shifted the research interest to the alternative fuel technologies. In particular, green diesel, vegetable oil/animal fat/waste oil and grease derived hydrocarbons in diesel boiling range, has become an attractive alternative to biodiesel— a mixture of fatty acid methyl esters, particularly due to its superior fuel properties that are similar to petroleum diesel. Hence, green diesel can be used as a drop-in fuel in the current diesel engines. The current technology for production of green diesel– hydrodeoxygenation of triglycerides and fatty acids over conventional hydrotreating …

A Comparative Study Of Three Different Chemical Vapor Deposition Techniques Of Carbon Nanotube Growth On Diamond Films, Betty T. Quinton, Paul N. Barnes, Chakrapani V. Varanasi, Bang-Hung Tsao, Kevin J. Yost, Sharmila M. Mukhopadhyay

Mechanical and Materials Engineering Faculty Publications

This paper compares between the methods of growing carbon nanotubes (CNTs) on diamond substrates and evaluates the quality of the CNTs and the interfacial strength. One potential application for these materials is a heat sink/spreader for high-power electronic devices. The CNTs and diamond substrates have a significantly higher specific thermal conductivity than traditional heat sink/spreader materials making them good replacement candidates. Only limited research has been performed on these CNT/diamond structures and their suitability of different growth methods. This study investigates three potential chemical vapor deposition (CVD) techniques for growing CNTs on diamond: thermal CVD (T-CVD), microwave plasma-enhanced CVD (MPE-CVD), …

Nanomaterials Synthesis, Applications, And Toxicity 2012, Mallikarjuna Nadagouda, Dionysios Demetriou Dionysiou, Darren A. Lytle, Thomas F. Speth, Sharmila M. Mukhopadhyay

Mechanical and Materials Engineering Faculty Publications

Nanotechnology presents new opportunities to create better materials and products. Nanomaterials find wide applications in catalysis, energy production, medicine, environmental remediation, automotive industry, and other sectors of our society. Nanomaterial-containing products are already available globally and include automotive parts, defense application, drug delivery devices, coatings, computers, clothing, cosmetics, sports equipment, and medical devices. This special issue includes emerging advances in the field, with a special emphasis given to nanomaterial synthesis and applications.

Microstructural Evolution During Stress Relaxation Of Gold Thin Films, Luthfia Amra Syarbaini

Open Access Theses

Microstructure evolution in metal thin films for use in microelectronic devices was studied due to the formation of defects such as whiskers and hillocks that may cause problems in electrical circuits. Thin film stress relaxation can occur through a variety of processes. Understanding such mechanisms and the conditions under which certain mechanism dominate can potentially lead to the improved control of thin film stability. Studies of the 3D microstructural changes in Au thin films on silicon and other substrates with different thermal expansion coefficients aid us in understanding thin film relaxation phenomena such as hillock/whisker formation. Techniques such as in-situ …

Multi-Scale Characterization Of Nanostructured Sodium Aluminum Hydride, Shathabish Narasegowda

Doctoral Dissertations

Complex metal hydrides are the most promising candidate materials for onboard hydrogen storage. The practicality of this class of materials is counter-poised on three critical attributes: reversible hydrogen storage capacity, high hydrogen uptake/release kinetics, and favorable hydrogen uptake/release thermodynamics. While a majority of modern metallic hydrides that are being considered are those that meet the criteria of high theoretical storage capacity, the challenges lie in addressing poor kinetics, thermodynamics, and reversibility. One emerging strategy to resolve these issues is via nanostructuring or nano-confinement of complex hydrides. By down-sizing and scaffolding them to retain their nano-dimensions, these materials are expected to …

Nano-Silicon/Graphene Composite Anodes For Enhanced Performance Lithium Ion Batteries, Rhet Joseph Caballes De Guzman

Wayne State University Dissertations

The ever evolving technological applications such as with portable electronics and electric vehicles have led to increasing energy demands that have proven the existing commercial LIB capacity insufficient. Recently, the most promising anode material to substitute the traditional graphite is Si. As an anode Si has low discharge potential and theoretical the highest known theoretical capacity (>10 fold of graphite). However, due to the increased accommodated Li+ during charge-discharge reactions, silicon's volume varies up to 400%, causing pulverization and loss of electrical contact.

This dissertation focuses on a systematic approach in developing effective means to utilize Si for improved …

Performance Qualification And Raman Investigation On Cell Behavior And Aging Of Lifepo₄ Cathodes In Lithium-Ion Batteries, Amir Salehi

Material Science and Engineering Theses - Archive

This thesis explores the ability of Raman spectroscopy to understand the complex chemistry taking place in LiFePO₄ cathodes of Li ion batteries. The performance of Li ion batteries was optimized through electrode fabrication and assembling procedures. Various amounts of Timcal Super P carbon were used to construct a conductive network of C-LiFePO₄ particles and the performance of the cathodes was examined during battery cycling. Raman spectroscopy along with electrochemical characterization such as charge/ discharge curves, electrochemical impedance spectroscopy and Cyclic Voltammetry was employed for detailed investigation of battery performance and aging. It is found that both quantity and quality of …

Effects Of Surface Plasmon Excitations On Photoluminescence By Cdse/Zns Quantum Dots, Ankit Kumar Singh

Material Science and Engineering Theses - Archive

The influence of localized surface plasmons (LSPs) and surface plasmon polaritons (SPPs) on the photoluminescence (PL) spectra of core/shell type CdSe/ZnS quantum dots (QDs) has been studied. Thin film samples of these QDs were deposited on glass slides, irradiated by 514 nm polarized beam from an Argon-ion laser, and PL spectra were measured using a high-resolution 1250M JY-Horiba spectrometer equipped with liquid-nitrogen cooled CCD detector. In the first set of experiments, PL spectra were measured on QDs and QDs-Au NPs mixture as a functions of the intensity of the 514 nm laser beam. In the second set of experiments, PL …

Synthesis Of Silver-Diamond Like Carbon Thin Films By Magnetron Sputtering, Venkatesh Majji

Material Science and Engineering Theses - Archive

Diamond-like carbon thin films are been used in wide range of applications due to their attractive tribological properties. Metal-doped DLC films have significant properties which make them compatible to use in larger variety of applications. The present study examines the dispersion and their effect on various tribological properties when Ag is incorporated into the DLC thin films. These Ag-DLC nanocomposite films were synthesized by a hybrid CVD and magnetron sputtering process in a discharge composed of CH4, and Ar atmosphere. These DLC and Ag-DLC films were characterized by Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy …

Role Of Engine Age And Lubricant Chemistry On The Characteristics Of Egr Soot, Olusanmi Adeniji Adeniran

Material Science and Engineering Theses - Archive

Exhaust products of Diesel Engines serves as an environmental hazard, and to curtail this problem a Tier 3 emission standard was introduced which involves change in engine designs and introduction of EGR systems in Diesel engines. EGR systems, however has the challenge of generating soot which are abrasive and are major causes of wear in Diesel engines. This work has studied the characteristics of EGR soot formed in different range of engine age and in different lubricant chemistries of Mineral and Synthetic based diesel Oils. It is found that lubricant degradation is encouraged by less efficient combustion as engine age …

Cold Plasma Treatment Of Magnetic Nanoparticles, Ke Wang

Material Science and Engineering Theses - Archive

This thesis investigates the application of cold plasma to remove the oleic acid bonded on magnetic nanoparticles: SmCo5 nanoflakes prepared via surfactant assisted high energy ball milling and CoFe2O4 nanoparticles prepared via chemical synthesis. Oleic acid molecules bonded on nanoparticles are in the carboxylate form which could not be washed away by organic solvents in ultrasonic bath; only free oleic acid molecules left on the nanoparticle surface after ball milling can be washed away through ultrasonic bath. High temperature annealing method works for removing oleic acid but nanoparticles would be damaged because of oxidation and decomposition.The RF cold plasma has …

Compaction Physics Of Solid Additive Blends : A Thermal Properties Study, Amy Brown

Material Science and Engineering Theses - Archive

Compacted solid additive blends have attracted the interest of the polymers industry due to their ability to improve processability. However, limited research has been performed to analyze the thermal properties that these additives have during pelletization.This research studies the reaction behavior of erucamide and silica, when in a pure and mixed form, with each other when thermal conductivity and frictional heating experiments are conducted. During the thermal conductivity study, it was found that pure erucamide had a thermal conductivity of 0.37 W/mK. The thermal conductivity of pure silica could not be found since silica will not compact to itself. Therefore, …

Synthesis And Characterization Of Transition Metal Arsenide Nanocrystals And The Metastability And Magneto-Structural Phase Transition Behavior Of Mnas Nanocrystals, Yanhua Zhang

Wayne State University Dissertations

This dissertation study focuses on (1) probing the magneto-structural phase transformation in nanoscale MnAs; (2) evaluation of the size-dependent phase stability of type-B MnAs (prepared by rapid injection); and (3) developing a general synthetic method for transition metal arsenide nanoparticles.

Discrete MnAs nanoparticles that adopt different structures at room temperature (type-A, α-structure and type-B, β-structure) have been prepared by the solution-phase arrested precipitation method. Atomic pair distribution and Rietveld refinement were employed on synchrotron data to explore the structural transitions of the bulk and nanoparticle samples, and these results were compared to AC magnetic susceptibility measurements of the samples. The …

Fabrication And Characterization Of Single Electron Device And Study Of Energy Filtering In Single Electron Transport, Liang-Chieh Ma

Material Science and Engineering Dissertations - Archive

Single electron devices, in which transport of single electrons is precisely controlled, hold a great promise as important components of future electronic devices and sensors. However, technical challenges have prevented their implementations to practical electronic and sensing systems. First of all, the fabrication of single electron devices requires their components to be defined and arranged in nanoscale precision, a great challenge for a large-scale fabrication. Secondly, for room temperature operation, the single-electron charging energy should be much larger than the room-temperature thermal energy, ~25 meV, requiring use of extremely small Coulomb island, which is difficult to control. This has limited …

Corrosion And Hydrogen Embrittlement Of Nanocrystalline Nickel, Tapas Desai

Material Science and Engineering Theses - Archive

Nanocrystalline (nc) materials have attracted the interest of the scientific community because of their unique physical and mechanical properties. However, limited research has been performed to analyze their electrochemical behavior. The majority of research in the field of electrochemical and corrosion behavior exists for electrodeposited nanocrystalline metals.This research studies the behavior of sputter-deposited nc Nickel films in corrosive and hydrogen environment by potentiodynamic polarization and microindentation. The surface morphology and composition of the samples was examined by Scanning Electron Microscopy and Energy Dispersive X-Ray spectroscopy. Bulk Ni samples exhibit mild passivation in 3.5 % NaCl solution. The surface reveals a …

Development Of Polymer Derived Sialcn Ceramic And Its Applications For High-Temperature Sensors, Gang Shao

Electronic Theses and Dissertations

Polymer-derived ceramic (PDC) is the name for a class of materials synthesized by thermal decomposition of polymeric precursors which excellent thermomechanical properties, such as high thermal stability, high oxidation/corrosion resistance and high temperature multifunctionalities. Direct polymer-to-ceramic processing routes of PDCs allow easier fabrication into various components/devices with complex shapes/structures. Due to these unique properties, PDCs are considered as promising candidates for making high-temperature sensors for harsh environment applications, including high temperatures, high stress, corrosive species and/or radiation. The SiAlCN ceramics were synthesized using the liquid precursor of polysilazane (HTT1800) and aluminum-sec-tri-butoxide (ASB) as starting materials and dicumyl peroxide (DP) as …

Barium Based Halide Scintillator Ceramics For Gamma Ray Detection, William Shoulders

Electronic Theses and Dissertations

As our understanding of ceramic processing methods for the purpose of fabricating polycrystalline optical materials has increased over the past few decades, the race is on to bring ceramic technology to markets where single crystalline materials have traditionally been used. One such market is scintillators. This Master’s thesis focuses specifically on a class of materials attractive for use as gamma-ray scintillators. These barium based halides can potentially be utilized in applications ranging from ionizing radiation detection in the field to high-energy physics experimentation. Barium bromide iodide and barium chloride single crystals have already showed high light yield, fast scintillation decay, …

Self-Assembled Two-Component Organic Tubes: Structures And Applications, Wenlang Liang

Electronic Theses and Dissertations

Bile acids are physiologically important metabolites, which are synthesized in liver as the end products of cholesterol metabolism and then secreted into the intestines. They play a critical role in the digestion and absorption of fats and fat-soluble vitamins through emulsifications. The amphipathic and chiral nature of bile acids makes their unique building blocks for assembling supramolecular structures including vesicles, fibers, ribbons and hollow tubes. Lithocholic acid (LCA) is a secondary bile acid. Our studies show LCA can selfassemble into helical tubes in aqueous solution by the linear aggregation and fusion of vesicles. The objective of this dissertation is to …

Engineering Nanoparticle And Nanoring Patterns For The Study Of Molecular Crystallization Under Nanoconfinement, Sunxi Wang

Wayne State University Dissertations

This dissertation focuses on generating the inorganic nanoparticle/organic nanorod hybrid nanostructures by the strategy of nanoparticle induced molecular crystallization developed by us and the new electrochemical method. We synthesize the gold nanoparticles with different sizes and functional groups and then fabricate the nanohybrids with fatty acid nanorods by spin coating method. Atomic force microscope monitors the topography of the hybrid nanostructures to help understand the underlying mechanism of the crystallization process. This successful self-assembled method could be used to fabricate nanohybrids based on seed-mediated nucleation. Also the novel "nano-flasks" have been generated by particle lithography method, which could be served …

Improving Tribological Properties Of Cast Al-Si Alloys Through Application Of Wear-Resistant Thermal Spray Coatings, David Culliton, Tony Betts, Sandra Carvalho, David Kennedy

Articles

Flame Spray Thermal Spray coatings are low-cost, high-wear surface-treatment technologies. However, little has been reported on their potential effects on cast automotive aluminum alloys. The aim of this research was to investigate the tribological properties of as-sprayed NiCrBSi and WC/12Co Flame Spray coatings applied to two cast aluminum alloys: high-copper LM24 (AlSi8Cu3Fe), and low-copper LM25 (AlSi7Mg). Potential interactions between the mechanical properties of the substrate and the deposited coatings were deemed to be significant. Microstructural, microhardness, friction, and wear (pin-on-disk, microabrasion, Taber abrasion, etc.) results are reported, and the performance differences between coatings on the different substrates were noted. The …

Diagnosis Of Systemic Inflammation Using Transendothelial Electrical Resistance And Low-Temperature Co-Fired Ceramic Materials, William L. Mercke

Theses and Dissertations--Chemical and Materials Engineering

Systemic inflammation involves a complex array of cytokines that can result in organ dysfunction. Mortality remains high despite the vast amount of research conducted to find an effective biomarker. The cause of systemic inflammation can be broad and non-specific; therefore, this research investigates using transendothelial electrical resistance (TEER) measurements to better define systemic inflammatory response syndrome (SIRS)/sepsis within a patient. Results show a difference in TEER measurements between healthy individuals and SIRS-rated patients. This research also displays correlations between TEER measurements and biomarkers currently studied with systemic inflammation (tumor necrosis factor-α, C- reactive protein, procalcitonin). Furthermore, this research also presents …

Rapid Repair Of Severely Damaged Rc Columns With Different Damage Conditions: An Experimental Study, Ruili He, Lesley Sneed, Abdeldjelil Belarbi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Interdiffusion Study Of Mg-Aa6061 System, Mian Fu

Electronic Theses and Dissertations

Magnesium (Mg) is a light-weight metal that has extraordinary physical and chemical properties for many potential applications in automobile, military, and electronics. Aluminum alloys, because of its light-weight, high strength and corrosion resistance have a wide range of commercial applications. Given these two, sometime competing, alloy systems, there are now many applications where the metallurgical compatibility of Mg- and Al-alloys are required for engineering applications. One such case is the development of diffusion barrier for U-Mo metallic fuel in Al-alloy cladding, where Mg, with its complete immiscibility with U and Mo is being considered as the diffusion barrier. While negligible …