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2013

Carbon nanotubes

Articles 1 - 13 of 13

Full-Text Articles in Engineering

Efficiently Dispersing Carbon Nanotubes In Polyphenylene Sulfide, Kevin M. Sommer, R. Byron Pipes Oct 2013

Efficiently Dispersing Carbon Nanotubes In Polyphenylene Sulfide, Kevin M. Sommer, R. Byron Pipes

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermal plastics are replacing conventional metals in the aerospace, sporting, electronics, and other industries. Thermal plastics are able to withstand relatively high temperatures, have good fatigue properties, and are lighter than metals. Unfortunately, they are not very electrically conductive. However, adding carbon nanotubes to thermal plastics such as polyphenylene sulfide (PPS) can drastically increase the plastic's conductivity at a low weight percent of nanotubes called the percolation threshold. The percolation threshold is the point where adding a little more carbon nanotubes brings together the network of nanotubes and greatly increases the conductivity. We need to learn how to increase the …

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Dna Based Carbon Nanotube Porphyrin Nanohybrids Molecular Recognization And Regeneration, Molly M. Riccitelli, Hanyu Zhang, Jong Hyun Choi Oct 2013

Dna Based Carbon Nanotube Porphyrin Nanohybrids Molecular Recognization And Regeneration, Molly M. Riccitelli, Hanyu Zhang, Jong Hyun Choi

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the search to improve solar cells, scientists are exploring new materials that will provide better current transfer. One material that has emerged as a strong contender is the single walled carbon nanotube (SWNT). Current DNA-SWNT based films combined with chromophores have poor operational lifetimes compared to commercial solar cells. Once exposed to light the chromophore begins to degrade, eventually rendering the solar cell unusable. To solve this problem, we used a method involving multiple steps. First we found which DNA sequences formed structures around the SWNT that could hold the most chromophores by using a spectrophotometer to test the …

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Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials, Brianna S. Carroll, Jong Hyun Choi Oct 2013

Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials, Brianna S. Carroll, Jong Hyun Choi

The Summer Undergraduate Research Fellowship (SURF) Symposium

Motor proteins such as kinesin move along microtubules in order to transport cellular cargos throughout the cell by obtaining energy from RNA hydrolysis which allows the cell to complete the tasks needed to stay alive. In this work, we developed synthetic molecular motors using DNA enzymes (DNAzyme) and fluorescent nanomaterials which mimic the functions and structures of motor proteins. A DNAzyme-capped CdS nanoparticle and a RNA-functionalized single-walled carbon nanotube (SWCNT) were used as a walker and a track in the motor platform, respectively. As a walking mechanism, the DNAzyme cleaved the RNA substrates in the presence of metal cations. The …

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Design Exploration And Analysis Of Carbon-Infiltrated Carbon Nanotube Vascular Stents, Darrell John Skousen Sep 2013

Design Exploration And Analysis Of Carbon-Infiltrated Carbon Nanotube Vascular Stents, Darrell John Skousen

Theses and Dissertations

The purpose of this research was to design, develop, and test coronary stent designs composed of carbon-infiltrated carbon nanotubes (CI-CNTs). Coronary stents currently have two major complications: restenosis and thrombosis. CI-CNT stents have potential to address both of these issues, and therefore may provide improved clinical outcomes. CI-CNT stent geometry is patterned using high-resolution photolithography that provide advantages in design possibilities.To develop a coronary stent, a standard design process was followed including: background, design specifications, concept generation, development, analysis, and testing. Background research was first completed and general design specifications for coronary stent performance were compiled. Multiple design concepts were …

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Development Of Advanced Nanomaterials For Potential Lithium-Ion Battery Application, Jian Liu Aug 2013

Development Of Advanced Nanomaterials For Potential Lithium-Ion Battery Application, Jian Liu

Electronic Thesis and Dissertation Repository

Lithium-ion batteries (LIBs) are promising energy storage media under serious consideration for practical applications in electric vehicle (EVs) and hybrid electric vehicles (HEVs). However, to meet the requirements for EVs and HEVs, the performance of commercially available LIBs needs to be greatly improved in terms of the energy density, cycling life, rate capability, safety and cost. It is well known that the LIB performance is highly dependent on the choice of electrode materials. Therefore, it is greatly important to develop new electrode materials as replacements for graphite/LiCoO2 used in commercial LIBs, in order to achieve high-performance LIBs desirable for …

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Nonlinear Dynamics Of Carbon Nanotubes Under Soft Alternating Current Actuation, Le Luo Aug 2013

Nonlinear Dynamics Of Carbon Nanotubes Under Soft Alternating Current Actuation, Le Luo

Theses and Dissertations - UTB/UTPA

This thesis work deals with electrostatically actuated Carbon Nanotubes (CNTs) cantilevers. Four forces are acting on the CNTs cantilever, namely damping, elastic, electrostatic and van der Waals forces. The van der Waals force is significant for values of 50 nm or lower of the gap between the CNTs and the ground substrate. As both electrostatic and van der Waals forces are nonlinear, and the CNTs electrostatic actuation is given by alternating current (AC) voltage, the CNTs undergo nonlinear parametric dynamics. The Method of Multiple Scales (MMS) and Reduced Order Model (ROM) are employed to investigate the system under soft excitation …

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Enhanced 3-Dimensional Carbon Nanotube Based Anodes For Li-Ion Battery Applications, Chi Won Kang Jun 2013

Enhanced 3-Dimensional Carbon Nanotube Based Anodes For Li-Ion Battery Applications, Chi Won Kang

FIU Electronic Theses and Dissertations

A prototype 3-dimensional (3D) anode, based on multiwall carbon nanotubes (MWCNTs), for Li-ion batteries (LIBs), with potential use in Electric Vehicles (EVs) was investigated. The unique 3D design of the anode allowed much higher areal mass density of MWCNTs as active materials, resulting in more amount of Li+ ion intake, compared to that of a conventional 2D counterpart. Furthermore, 3D amorphous Si/MWCNTs hybrid structure offered enhancement in electrochemical response (specific capacity 549 mAhg-1). Also, an anode stack was fabricated to further increase the areal or volumetric mass density of MWCNTs. An areal mass density of the anode …

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An Exploration Of Carbon-Filled Carbon Nanotubes As A Potential Material In Coronary Stents, Kristopher Neil Jones May 2013

An Exploration Of Carbon-Filled Carbon Nanotubes As A Potential Material In Coronary Stents, Kristopher Neil Jones

Theses and Dissertations

The purpose of this research is to explore the potential of using carbon-infiltrated carbon nanotubes (CI-CNT) as a material for coronary artery stents. Stents are commonly fabricated from metal, which may not perform as well as many polymers and ceramics in biomedical applications. Pyrolytic carbon, a ceramic, is currently used in medical implant devices due to its preferrable biocompatibility properties. Micro-patterned pyrolytic carbon devices can be created by growing carbon nanotubes, and then filling the space between with amorphous carbon via chemical vapor deposition. We prepared multiple samples of two different planar stent-like flexible geometries and smaller cubic structures out …

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Gravimetric Chemical Sensor Based On The Direct Integration Of Swnts On Aln Contour-Mode Mems Resonators, Matteo Rinaldi, Chiara Zuniga, Nipun Sinha, Marzie Taheri, Samuel M. Khamis, Alan T. Johnson, Gianluca Piazza Feb 2013

Gravimetric Chemical Sensor Based On The Direct Integration Of Swnts On Aln Contour-Mode Mems Resonators, Matteo Rinaldi, Chiara Zuniga, Nipun Sinha, Marzie Taheri, Samuel M. Khamis, Alan T. Johnson, Gianluca Piazza

Matteo Rinaldi

This paper reports on the first demonstration of a gravimetric chemical sensor based on direct integration of Single Wall Carbon Nanotubes (SWNTs) grown by Chemical Vapor Deposition (CVD) on AlN Contour-Mode MicroElectroMechanical (MEMS) resonators. In this first prototype the ability of SWNTs to readily adsorb volatile organic chemicals has been combined with the capability of AlN Contour-Mode MEMS resonator to provide for different levels of sensitivity due to separate frequencies of operation on the same die. Two devices with resonance frequencies of 287 MHz and 442 MHz have been exposed to different concentrations of DMMP in the range from 80 …

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Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza Feb 2013

Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza

Matteo Rinaldi

A nanoenabled gravimetric chemical sensor prototype based on the large scale integration of single-stranded DNA (ss-DNA) decorated single-walled carbon nanotubes (SWNTs) as nanofunctionalization layer for aluminum nitride contour-mode resonant microelectromechanical (MEM) gravimetric sensors has been demonstrated. The capability of two distinct single strands of DNA bound to SWNTs to enhance differently the adsorption of volatile organic compounds such as dinitroluene (simulant for explosive vapor) and dymethyl-methylphosphonate (simulant for nerve agent sarin) has been verified experimentally. Different levels of sensitivity (17.3 and 28 KHz µm^2/fg) due to separate frequencies of operation (287 and 450 MHz) on the same die have also …

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Nano-Particles In Multi-Scale Composites And Ballistic Applications, Jason Gibson Jan 2013

Nano-Particles In Multi-Scale Composites And Ballistic Applications, Jason Gibson

Electronic Theses and Dissertations

Carbon nanotubes, graphene and nano sized core shell rubber particles have all been extensively researched for their capability to improve mechanical properties of thermoset resins. However, there has been a lack of research on their evaluation for energy absorption in high velocity impact scenarios, and the fundamental mechanics of their failure mechanisms during highly dynamic stress transfer through the matrix. This fundamental research is essential for laying the foundation for improvement in ballistic performance in composite armor. In hard armor applications, energy absorption is largely accomplished through delamination between plies of the composite laminate. This energy absorption is accomplished through …

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Multiscale Modeling Of Liquid Crystalline/Nanotube Composites, Sharil Patrale Jan 2013

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 …

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Electrical And Optical Characterization Of Carbon Nanotube Diodes, Argyrios Malapanis Jan 2013

Electrical And Optical Characterization Of Carbon Nanotube Diodes, Argyrios Malapanis

Legacy Theses & Dissertations (2009 - 2024)

Carbon nanotubes are good candidates for future applications, including nanoelectronic and nanophotonic devices. Their quasi-one dimensional (1D) character offers appealing device properties. These include reduced carrier scattering, carrier mobility up to two orders of magnitude higher than that of materials used in state-of-the-art computer chips today, current densities rivaling those of the best semiconductors, enhanced optical absorption, and band gaps tunable with tube diameter and doping. Recent breakthroughs in research point to the possibility of placing nanotubes precisely on substrates with densities approaching that of transistors on today's computer chips in a way that's integratable with existing Si-based technology. Such …

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