Engineering Commons^™

Control Of Light-Matter Interaction Via Dispersion Engineering, Harish Natarajan Swaha Krishnamoorthy

Dissertations, Theses, and Capstone Projects

This thesis describes the design, fabrication and characterization of certain nanostructures to engineer light-matter interaction. These materials have peculiar dispersion properties owing to their structural design, which is exploited to control spontaneous emission properties of emitters such as quantum dots and dye molecules. We will discuss two classes of materials based on the size of their unit cell compared to the wavelength of the electromagnetic radiation they interact with. The first class are hyperbolic metamaterials (HMM) composed of alternate layers of a metal and a dielectric of thicknesses much smaller than the wave- length. Using a HMM composed of silver …

Synthesis And Evaluation Of Sensitizer Drug Photorelease Chemistry: Micro-Optic Method Applied To Singlet Oxygen Generation And Drug Delivery, Goutam Ghosh

Dissertations, Theses, and Capstone Projects

This thesis summarizes a new micro-optic method for singlet oxygen generation and sensitizer drug delivery, which include i) synthesis and evaluation of a first generation device for drug delivery from native and fluorinated silica probe tips, ii) synthesis of PEG conjugated sensitizers to study phototoxicity in ovarian cancer cells, and iii) synthesis and evaluation of tris-PEGylated chlorin conjugated fluorinated silica for its future integration into the device to use as a 2nd generation device. A first generation micro-optic device was developed that works by sparging O2 gas and light generating cytotoxic singlet oxygen that cleaves the covalently attached drug (sensitizer) …

Transport And Optical Properties Of Low-Dimensional Complex Systems, Andrii Iurov

Dissertations, Theses, and Capstone Projects

Over the last five years of my research work, I, my research was mainly concerned with certain crucial tunneling, transport and optical properties of novel low-dimensional graphitic and carbon-based materials as well as topological insulators. Both single-electron and many-body problems were addressed. We investigated the Dirac electrons transmission through a potential barrier in the presence of circularly polarized light. An anomalous photon-assisted enhanced transmission is predicted and explained in a comparison with the well-known Klein paradox. It is demonstrated that the perfect transmission for nearly-head-on collision in an infinite graphene is suppressed in gapped dressed states of electrons, which is …

Cited2-Mediated Mechanotransduction And Its Use For Chondroprotection, Daniel J. Leong

Dissertations, Theses, and Capstone Projects

Novel prevention and therapeutic treatment for cartilage degradation is urgently called for, as cartilage degradation is a hallmark for arthritic diseases including osteoarthritis (OA) and rheumatoid arthritis (RA), and there is a high incidence of arthritis-related disability and high medical costs. While both underuse (e.g. physically inactive lifestyle) and overuse (e.g. high impact or intense repetitive joint use as seen in certain sports) are risk factors for cartilage degradation, recent studies highlight that dynamic moderate loading is associated with reduced incidence of developing OA. Exercise is prescribed in most cases at moderate levels for both OA and RA patients, and …

Synthesis, Fabrication And Characterization Of Magnetic And Dielectric Nanoparticles And Nanocomposite Films, Xiaohua Liu

Dissertations, Theses, and Capstone Projects

Materials science is an interdisciplinary field investigating the structure-property relationship in solid-state materials scientifically and technologically. Nanoscience is concerned with the distinctive properties that matter exhibits when confined to physical dimensions on the order of 10^-9 meters. At these length scales, behaviors of particles or elaborate structures are often governed by the rules of quantum mechanics in addition to the physical properties associated with the bulk material.

The work reported here seeks to employ nanocystals, binary nanocomposites and thin films of materials, to build versatile, functional systems and devices. With a focus on dielectric, ferroelectric, and magnetoelectric performance, a …

Nuclear Magnetic Resonance Studies On Lithium And Sodium Electrode Materials For Rechargeable Batteries, Tetiana Nosach

Dissertations, Theses, and Capstone Projects

In this thesis, Nuclear Magnetic Resonance (NMR) spectroscopic techniques are used to study lithium and sodium electrode materials for advanced rechargeable batteries. Three projects are described in this thesis. The first two projects involve 6Li, 7Li and 31P NMR studies of two cathode materials for advanced rechargeable batteries. The third project is a study of sodium titanate cathode materials for Na-ion batteries, where 1H, 7Li, and 23Na static and magic angle spinning NMR were used in order to obtain detailed information on the chemical environments.

Dynamics Of Nanoparticles In Fluids And At Interfaces, Weikang Chen

Dissertations, Theses, and Capstone Projects

In this thesis, we use molecular dynamics simulation to study three basic behaviors or properties of nanoparticles: deposition during droplets evaporation, slip boundary condition and Brownian motion. These three problems address the need for an in-depth understanding of the dynamics of nanoparticles in fluids and at interfaces. In the first problem, evaporation of the droplets dispersed with particles, we investigated the distribution of evaporative flux, inner flow field, density and temperature. And we use these numerical experiments to check on our hydrodynamic theory of the "coffee ring" phenomenon. The simulations reveal the connection between the particle interactions and the deposit …

Characterization Of Wide Band Gap Semiconductors And Multiferroic Materials, Bo Cai

Dissertations, Theses, and Capstone Projects

Structural, optical and electrical properties of zinc oxide (ZnO), aluminum nitride (AlN), and lutetium ferrite (LuFe₂O4) have been investigated. Temperature dependent Hall Effect measurements were performed between 80 and 800 K for phosphorus (P) and arsenic (As) doped ZnO thin films grown on c-plane sapphire substrate by RF magnetron sputtering. These samples exhibited n-type conductivity throughout the temperature range with carrier concentration of 3.85 × 10 ¹⁶ cm^-3 and 3.65 × 10 ¹⁷ cm^-3 at room temperature for P-doped and As-doped ZnO films, respectively. The Arrhenius plots of free electron concentration of those doped samples showed …

Water Conservation To Reduce Wet Weather Pollution Loads To The Gowanus Canal, Brooklyn, Ny, Suzanne Carol Stempel

Dissertations, Theses, and Capstone Projects

Public participation plays an important role in wet weather pollution management. However, the effects of participation programs on local water quality are often difficult to quantify. This project aims to quantify the potential effects of a community based, non-structural, BMP aimed at controlling inputs to combined sewage systems by encouraging residents to reduce their water use during rain events. A household could participate by reducing the amount of water they use for flushing toilets, washing dishes, taking showers, etc. during rain events; thereby reducing stress on the system during the time of highest demand. The Gowanus Canal sewershed in Brooklyn, …

Design Of Well-Defined Mesoporous Silicas Via Surfactant Templating Method Enhanced By The Use Of Swelling Agents, Tiffany Man

Dissertations, Theses, and Capstone Projects

Surfactant-templated ordered mesoporous materials continue to attract tremendous attention as these materials are characterized by reproducibility and predictability of their synthesis as well as their wide range of potential applications, which serve as future opportunities for additional advancement. The main purpose of this dissertation is to advance the understanding how to control the structural features and properties in the synthesis of well-defined porous materials via surfactant templating method, while keeping in mind that the uniformity of pore size and structural ordering are essential characteristics for these well-defined materials. The work was primarily focused on the issue of the unit-cell size …

An Innovative Ran Architecture For Emerging Heterogeneous Networks: "The Road To The 5g Era", Shahab Hussain

Dissertations, Theses, and Capstone Projects

The global demand for mobile-broadband data services has experienced phenomenal growth over the last few years, driven by the rapid proliferation of smart devices such as smartphones and tablets. This growth is expected to continue unabated as mobile data traffic is predicted to grow anywhere from 20 to 50 times over the next 5 years. Exacerbating the problem is that such unprecedented surge in smartphones usage, which is characterized by frequent short on/off connections and mobility, generates heavy signaling traffic load in the network "signaling storms". This consumes a disproportion amount of network resources, compromising network throughput and efficiency, and …

Metal Nanoparticles Immobilized On Basic Supports As Catalysts For Hydrogenation And Dehydrogenation Reactions Of Relevance To Cleaner Fossil Fuels And Alternative Sources Of Energy, Reena Rahi

Dissertations, Theses, and Capstone Projects

We developed a series of catalysts, composed of metal nanoparticles immobilized on basic supports for the hydrogenation of heteroaromatics of relevance to cleaner fossil fuels and biodiesel, and for the dehydrogenation of heteroaromatics of relevance to hydrogen storage in organic liquids. Our catalyst design involves nanostructured catalysts composed of metal particles immobilized on basic supports capable of ionic mechanism that may avoid catalyst poisoning and enhance catalytic activity.

We prepared a new catalyst composed of Pd nanoparticles immobilized on MgO by NaBH4 reduction of Na2PdCl4 in methanol in the presence of the support. TEM measurements revealed well-dispersed 1.7 nm Pd …

Hydrodynamic And Mass Transport Properties Of Microfluidic Geometries, Thomas F. Leary

Dissertations, Theses, and Capstone Projects

Microfluidic geometries allow direct observation of microscale phenomena while conserving liquid volumes. They also enable modeling of experimental data using simplified transport equations and static force balances. This is possible because the length scales of these geometries ensure low Re conditions approaching the Stokesian limit, where the flow profile is laminar, viscous forces are dominant and inertial forces are negligible. This work presents results on two transport problems in microfluidic geometries. The first examines the heterogeneous binding kinetics in a microbead array, where beads with different chemical functionalities are sequentially captured in a well geometry over which analyte solution is …

Magnetic Janus Particles And Their Applications, Bin Ren

Dissertations, Theses, and Capstone Projects

Magnetic properties are important since they enable the manipulation of particle behavior remotely and therefore provide the means to direct a particle’s orientation and translation. Magnetic Janus particles combine magnetic properties with anisotropy and thus are potential building blocks for complex structures that can be assembled from a particle suspension and can be directed through external fields. In this thesis, a method for the fabrication of three types of magnetic Janus particles with distinct magnetic properties is introduced, the assembly behavior of magnetic Janus particles in external magnetic and electric fields is systematically studied, and two potential applications of magnetic …

Reliability-Based Progressive Collapse And Redundancy Analysis Of Bridge Systems, Feng Miao

Dissertations, Theses, and Capstone Projects

Highway bridges like most structural systems are usually designed on a member by member basis and little consideration is provided to the effect of a local failure on system safety. There are concerns that some systems optimized to meet code-specified member design criteria may not provide sufficient levels of structural redundancy to withstand a possible local failure. In fact, a local failure of one structural element may result in the failure of another element creating a chain reaction that might progress throughout the whole structure or a major portion of it leading to a catastrophic collapse. Several recent catastrophic structural …

Organic Pi-Stacking Semiconducting Material: Design, Synthesis And The Analysis Of Structure And Properties, Bin Wang

Dissertations, Theses, and Capstone Projects

Organic semiconducting materials have been under intensive investigation in the recent decades for potential applications in various electronic or optoelectronic devices such as light emitting diodes, photovoltaic cells and field effect transistors. Compared to inorganic counterparts, organic charge transport materials are attractive for their abilities of forming thin-films, large area manufacturing, compatibility with flexible substrate, light weight and potential low fabrication cost. The charge transport property of the organic active layer is one of the key factors to the electronic or optoelectronic performance of devices. Research projects presented in this thesis focused on improving charge carrier mobility of organic charge …

Colloidal Quantum Dot Based Photonic Circuits And Devices, Nicky E. Okoye

Dissertations, Theses, and Capstone Projects

Colloidal quantum dots have desirable optical properties which can be exploited to realize a variety of photonic devices and functionalities. However, colloidal dots have not had a pervasive utility in photonic devices because of the absence of patterning methods. The electronic chip industry is highly successful due to the well-established lithographic procedures. In this thesis we borrow ideas from the semiconductor industry to develop lithographic techniques that can be used to pattern colloidal quantum dots while ensuring that the optical properties of the quantum dots are not affected by the process. In this thesis we have developed colloidal quantum dot …

2d & 3d Nanomaterial Fabrication With Biological Molecular Frameworks, Kristina Ivana Fabijanic

Dissertations, Theses, and Capstone Projects

Recently, there has been a heightened amount of work done in the field of biomineralization. By taking inspiration from natures' phenomenonal individualities as a means to develop new and interesting nanostructures of varying sizes and dimensions, there is a newly developed design, namely Biomimetic Crystallization Nanolithography (BCN). With this method, the simultaneous nano-patterning and crystallization has been achieved using urease as the nucleation point and the hydrolysis of urea to obtain patterns of oxide semiconductor material, namely zinc oxide, at room temperature and aqueous solvent. The new and interesting characteristic of BCN involves the construction of amorphous inks of ZnO …

On The Merits Of Deploying Tdm-Based Next-Generation Pon Solutions In The Access Arena As Multiservice, All Packet-Based 4g Mobile Backhaul Ran Architecture, Syed Rashid N. Zaidi

Dissertations, Theses, and Capstone Projects

The phenomenal growth of mobile backhaul capacity required to support the emerging fourth-generation (4G) traffic including mobile WiMAX, cellular Long-Term Evolution (LTE), and LTE-Advanced (LTE-A) requires rapid migration from today's legacy circuit switched T1/E1 wireline and microwave backhaul technologies to a new fiber-supported, all-packet-based mobile backhaul infrastructure. Clearly, a cost effective fiber supported all-packet-based mobile backhaul radio access network (RAN) architecture that is compatible with these inherently distributed 4G RAN architectures is needed to efficiently scale current mobile backhaul networks. However, deploying a green fiber-based mobile backhaul infrastructure is a costly proposition mainly due to the significant cost associated with …

Scheduling And Resource Allocation In Wireless Sensor Networks, Yosef Alayev

Dissertations, Theses, and Capstone Projects

In computer science and telecommunications, wireless sensor networks are an active research area. Each sensor in a wireless sensor network has some pre-defined or on demand tasks such as collecting or disseminating data. Network resources, such as broadcast channels, number of sensors, power, battery life, etc., are limited. Hence, a schedule is required to optimally allocate network resources so as to maximize some profit or minimize some cost. This thesis focuses on scheduling problems in the wireless sensor networks environment. In particular, we study three scheduling problems in the wireless sensor networks: broadcast scheduling, sensor scheduling for area monitoring, and …

Property Enhancements Of Dielectric Nanoparticles Via Surface Functionalization, Andrew Byro

Dissertations, Theses, and Capstone Projects

This thesis describes the surface modification of barium strontium titanate nanoparticles for use in polymer/ceramic composite thin film capacitors with resultant improved dielectric and film-making properties. Phosphonic acid-type ligands proved to be most effective for surface conjugation to the surface of the barium strontium titanate nanoparticles. Amine-terminated ligands proved to be effective at removing surface adsorbed water before being almost entirely removed during the sample washing stage. Carboxylic acid terminated ligands proved to adhere less well to the nanoparticle than the phosphonic acid, but resulted in thin films with a higher dielectric constant, which was more stable in the measured …

Fabrication And Assembly Of Patchy Particles With Uniform Patches, Zhenping He

Dissertations, Theses, and Capstone Projects

Patchy colloidal particles have been widely studied as the self-assembly building blocks to illustrate their potential for forming complex structures. The parameters affecting the final assembly structures include (i) patch size, shape, and number per particle, (ii) their relative positions, and (iii) the surface properties of the patch material. Recent computational studies have highlighted the impact of patch shape on assembly structure; however, there are only a limited number of methods that can provide control over patch shape and size. In this thesis, a template is introduced to the Glancing Angle Vapor Deposition method (GLAD) to create surface anisotropy on …

Optical Properties Of Solar Cells Based On Zinc(Hydr)Oxide And Its Composite With Graphite Oxide Sensitized By Quantum Dots, S. M. Zakirul Islam

Dissertations, Theses, and Capstone Projects

This thesis research focuses on developing a hybrid form of solar cell based on zinc(hydr)oxide and its composites with graphite oxide, TiO2, quantum dot, electrolyte and . This work expands upon the Gratzel solar cell with a dye in TiO2.

Due to various structural and optical characteristics, zinc(hydr)oxide (Zn(OH)2) and its porous composites with 2% and 5% graphite oxide(GO) can be used for various applications including the manufacture of various , protective elements in electric and electronic appliances, as gas-sensors, catalysts, in cosmetics a UV light absorber, and solar cells.

In this research, both TiO2 and zinc(hydr)oxide (refer as Zn(OH)2 …

Design And Performance Analysis Of Genetic Algorithms For Topology Control Problems, Cem Safak Sahin

Dissertations, Theses, and Capstone Projects

In this dissertation, we present a bio-inspired decentralized topology control mechanism, called force-based genetic algorithm (FGA), where a genetic algorithm (GA) is run by each autonomous mobile node to achieve a uniform spread of mobile nodes and to provide a fully connected network over an unknown area. We present a formal analysis of FGA in terms of convergence speed, uniformity at area coverage, and Lyapunov stability theorem.

This dissertation emphasizes the use of mobile nodes to achieve a uniform distribution over an unknown terrain without a priori information and a central control unit. In contrast, each mobile node running our …

Synergistic Surfactant Interactions And The Consequences On Phase Behavior, Interfacial Tension Reduction And Hydrophobic Surface Wetting, Makonnen Mateós Payne

Dissertations, Theses, and Capstone Projects

The ability for some of the nonionic trisiloxane surfactants to completely and rapidly wet a hydrophobic surface has been well documented for several years. However, to date, the behavior of the trisiloxane surfactants at the solid-liquid interface is not yet completely understood, leading to an incomplete understanding of the mechanism for complete wetting. In this work we report our findings with regard to the synergistic interactions between polyethylene oxide surfactants of the general structure CiE j and compare the behavior to a known super wetting surfactant. Pendant drop tensiometry experiments and sessile drop contact angle measurements on hydrophobic surfaces were …

The Social Construction Of Authorship: An Investigation Of Subjectivity And Rhetorical Authority In The College Writing Classroom, Johannah Rodgers

Dissertations, Theses, and Capstone Projects

Although we use the term author on a daily basis to refer to certain individuals, bodies of work, and systems of ideas, as Michel Foucault and other critics have pointed out, attempting to answer the question “What is an Author?” is by no means a simple proposition. And, starting from the position that there is no single, or definitive answer to this complex question, this dissertation seeks to contribute to the ongoing discussion of the genealogy of authorship by investigating the ways in which conceptions of the author have informed models of the writing subject in the field of rhetoric …