Nanoscience and Nanotechnology Commons^™

Hybrid Opto-Electrokinetic Technique For Micro/Nanomanipulation: Towards Application Of A Novel Non-Invasive Manipulation Technique In Microbiological Assay, Jae-Sung Kwon

Open Access Dissertations

This dissertation explores various physical mechanisms of the Rapid Electrokinetic Patterning (REP) technique suggested for rapid and precise on-chip manipulation of colloids and fluids, and bio-compatibility of the technique for biological applications. REP is a hybrid opto-electrokinetic technique that is driven by the simultaneous application of an AC electric field and a heating source. It can not only effectively transport and manipulate a fluid but also concentrate and pattern particles suspended in the fluid through the combined effect of an electrohydrodynamic flow, electrostatic colloidal interactions and an electrothermal microfluidic flow. These capabilities make REP a promising tool which can provide …

Graphene Decorated Substrates And Their Interfacial Characteristics, Anurag Kumar

Open Access Dissertations

Carbon nanotubes and graphene have been extensively studied for their excellent properties. As research on carbon expands, two major issues face the scientific community: (i) Expanding the scale of synthesis and (ii) Integration of different carbon structures for improved functionality. While significant advancements have been made in large-scale synthesis, room for improvement remains. As the scale of production increases, issues such as time, cost and energy that may otherwise not be very significant, begin to play greater roles. Thus, in order to effectively transition from laboratory prototypes to industrial products, a synthesis method that can address these issues is strongly …

Micro Solar Thermal Energy Development And Use For Mems Power Applications, Emmanuel Ogbonnaya

Doctoral Dissertations

Increasing focus on alternative energy sources has produced significant progress across a wide variety of research areas. One particular area of interest has been solar energy. The sun represents sustainable and renewable energy source capable of meeting present energy needs without compromising the ability of future generations to meet theirs. Energy from the sun can be utilized in multiple ways. Direct rise in modern power generation typically involves either photovoltaic systems or large-scale solar thermal energy installations. While large-scale solar thermal energy generation is well advanced, there has been comparatively little research on smaller scale thermal energy collection and application. …

Plasmonics Resonance Enhanced Active Photothermal Effects In Aluminum Nanoenergetics For Propulsion Applications, Jacques Abboud

Doctoral Dissertations

In this dissertation, aluminum nanoparticles (Al NPs) are shown capable to on-demand enhance and control the local photothermal energy deposition, both spatially and temporally, via active photothermal effects initiated by the localized surface plasmon resonance (LSPR) phenomenon, and amplified by the Al exothermal oxidation reactions. Experiments in dry and wet environments along with computational modeling of the photothermal process are very desirable for gaining fundamental understanding, ignition optimization and parameter exploration.

Combined phenomena of motion and ignition of Al NPs are explored first in this study. Both resulting from exposing a pile of the nanoenergetics in hand to a single …

Design And Fundamental Understanding Of Minimum Quantity Lubrication (Mql) Assisted Grinding Using Advanced Nanolubricants, Parash Kalita

Graduate Theses and Dissertations

Abrasive grinding is widely used across manufacturing industry for finishing parts and components requiring smooth superficial textures and precise dimensional tolerances and accuracy. Unlike any other machining operations, the complex thermo-mechanical processes during grinding produce excessive friction-induced energy consumption, heat, and intense contact seizures. Lubrication and cooling from grinding fluids is crucial in minimizing the deleterious effects of friction and heat to maximize the output part quality and process efficiency. The conventional flood grinding approach of an uneconomical application of large quantities of chemically active fluids has been found ineffective to provide sufficient lubrication and produces waste streams and pollutants …

Micro-Mechanical Assessment Of The Local Plastic Strain Invoked During A Splined Mandrel Flow Forming Operation, Meysam Haghshenas

Electronic Thesis and Dissertation Repository

Splined Mandrel Flow Forming (SMFF) is a metal spinning operation that involves the application of high multiaxial compressive stress states to invoke large plastic flow in the work piece. This allows for essentially one-step fabrication of complex internally-splined shapes. In this research project, the equivalent plastic strain, invoked throughout bcc (1020 steel) and fcc (5052 and 6061 aluminum alloys, pure copper, and 70/30 brass) samples, that were made by SMFF, was measured. The objective of the research were to measure the to obtain data on the effect of microstructure and mechanical parameters on the flow formability of ductile bcc and …

Vibration And Buckling Of Carbon Nanotube, Graphene, And Nanowire, Mohammad Hadi Mahdavi

Electronic Thesis and Dissertation Repository

Nanostructured materials with superior physical properties hold promise for the development of novel nanodevices. Full potential applications of such advanced materials require accurate characterization of their physical properties, which in turn necessitates the development of computer-based simulations along with novel experimental techniques. Since controlled experiments are difficult for nanoscale materials and atomic studies are computationally expensive, continuum mechanics-based simulations of nanomaterials and nanostructures have become the focal points of computational nano-science and materials modelling.

In this study, emphasis is given to predicting the mechanical behaviour of carbon nanotube (CNT), graphene, nanowire (NW), and nanowire encapsulated in carbon nanotube (NW@CNT), which …

Multiscale Modeling Of Liquid Crystalline/Nanotube Composites, Sharil Patrale

Dissertations, Master's Theses and Master's Reports - Open

The objective of this research is to synthesize structural composites designed with particular areas defined with custom modulus, strength and toughness values in order to improve the overall mechanical behavior of the composite. Such composites are defined and referred to as 3D-designer composites. These composites will be formed from liquid crystalline polymers and carbon nanotubes. The fabrication process is a variation of rapid prototyping process, which is a layered, additive-manufacturing approach. Composites formed using this process can be custom designed by apt modeling methods for superior performance in advanced applications. The focus of this research is on enhancement of Young's …

Co-Electrophoretic Deposition Of Liquid Metal And Silicon For Lithium-Ion Battery Application, Hanfei Zhang

Dissertations, Master's Theses and Master's Reports - Open

A low cost electrophoretic deposition (EPD) process was successfully used for liquid metal thin film deposition with a high depositing rate of 0.6 µ/min. Furthermore, silicon nano-powder and liquid metal were then simultaneously deposited as the negative electrode of lithium-ion battery by a technology called co-EPD. The liquid metal was hoping to act as the matrix for silicon particles during lithium ion insertion and distraction. Half-cell testing was performed using as prepared co-EPD sample. An initial discharge capacity of 1500 mAh/g was reported for nano-silicon and galinstan electrode, although the capacity fading issue of these samples was also observed.

High Voltage Electrophoretic Deposition For Electrochemical Energy Storage And Other Applications, Sunand Santhanagopalan

Dissertations, Master's Theses and Master's Reports - Open

High voltage electrophoretic deposition (HVEPD) has been developed as a novel technique to obtain vertically aligned forests of one-dimensional nanomaterials for efficient energy storage. The ability to control and manipulate nanomaterials is critical for their effective usage in a variety of applications. Oriented structures of one-dimensional nanomaterials provide a unique opportunity to take full advantage of their excellent mechanical and electrochemical properties. However, it is still a significant challenge to obtain such oriented structures with great process flexibility, ease of processing under mild conditions and the capability to scale up, especially in context of efficient device fabrication and system packaging. …

Near Wall Shear Stress Modification Using An Active Piezoelectric Nanowire Surface, Christopher R. Guskey

Theses and Dissertations--Mechanical Engineering

An experimental study was conducted to explore the possible application of dynamically actuated nanowires to effectively disturb the wall layer in fully developed, turbulent channel flow. Actuated nanowires have the potential to be used for the mixing and filtering of chemicals, enhancing convective heat transfer and reducing drag. The first experimental evidence is presented suggesting it is possible to manipulate and subsequently control turbulent flow structures with active nanowires. An array of rigid, ultra-long (40 μm) TiO₂ nanowires was fabricated and installed in the bounding wall of turbulent channel flow then oscillated using an attached piezoelectric actuator. Flow velocity …

Application Of Nano-Imprint Lithography For Next Generation Carbon Nanotube-Based Devices, Svitlana Fialkova

Dissertations

This research report addresses the development of 3D carbon nanostructures that can provide unique capabilities for manufacturing carbon nanotube (CNT) electronic components, electrochemical probes, biosensors and tissue scaffolds. The shaped CNT arrays were grown on patterned catalytic substrate by chemical vapor deposition (CVD) method. The new fabrication process for catalyst patterning based on combination of nano-imprint lithography (NIL), magnetron sputtering and reactive etching techniques was proposed and studied. The optimal process parameters for each technique were evaluated. The catalyst was made by deposition of Fe and Co nanoparticles over alumina support layer on Si/SiO₂ substrate. The metal particles were …

Numerical Modeling And Characterization Of Vertically Aligned Carbon Nanotube Arrays, Johnson Joseph

Theses and Dissertations--Mechanical Engineering

Since their discoveries, carbon nanotubes have been widely studied, but mostly in the forms of 1D individual carbon nanotube (CNT). From practical application point of view, it is highly desirable to produce carbon nanotubes in large scales. This has resulted in a new class of carbon nanotube material, called the vertically aligned carbon nanotube arrays (VA-CNTs). To date, our ability to design and model this complex material is still limited. The classical molecular mechanics methods used to model individual CNTs are not applicable to the modeling of VA-CNT structures due to the significant computational efforts required. This research is to …