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An Improvement Of Current Driving And Electrical Conductivity Properties Incovetics, Mesut Atasoyu, Emi̇n Argun Oral, Mehmet Ertuğrul

Turkish Journal of Physics

Compared to pure Cu, Cu lattice retaining carbon atoms, called a covetic material, can have better electrical conductivity. Furthermore, the incorporation of carbon nanostructures into Cu-alloys could improve the mechanical properties of Cu-alloys. In the simulation study, we investigated Joule heating due to applied DC current on molten Cu metal concerning how to improve current density of covetic materials. In addition, we will discuss interfacial effects on covetic-metal electrodes to meet better current driving performance. The covetic composite excited at one electrode (width = 10 nm) has a higher current drive capability as a value of 3.54 $10^{7}$ $A /m^{2}$, …

Development Of The Carbon Nanotube Thermoacoustic Loudspeaker, Troy Bouman

Dissertations, Master's Theses and Master's Reports

Traditional speakers make sound by attaching a coil to a cone and moving that coil back and forth in a magnetic field (aka moving coil loudspeakers). The physics behind how to generate sound via this velocity boundary condition has largely been unchanged for over a hundred years. Interestingly, around the time moving coil loudspeakers were first investigated the idea of using heat to generate sound was also known. These thermoacoustic speakers heat and cool a thin material at acoustic frequencies to generate the pressure wave (i.e. they use a thermal boundary condition). Unfortunately, when the thermoacoustic principle was initially discovered …

Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Vi, Leonid A. Ivanov, Li D. Xu, Konstantin E. Razumeev, Zhanna V. Pisarenko, Aleksey V. Demenev

Information Technology & Decision Sciences Faculty Publications

Introduction. Advanced technologies impress people's imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries. Main part. The article provides an abstract overview of inventions of scientists, engineers and specialists from different countries: Russia, USA, China, Kazakhstan, Sweden. The results of the creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials allow, when introduced to industry, achieving a significant effect in construction, housing and communal services, and related sectors of the …

Concurrent Application Of Conductive Biopolymeric Chitosan/ Polyvinyl Alcohol/ Mwcnts Nanofibers, Intracellular Signaling Manipulating Molecules And Electrical Stimulation For More Effective Cardiac Tissue Engineering, Ali Abedi, Behnaz Bakhshandeh, Ali Babaie, Javad Mohammadnejad, Sadaf Vahdat, Reza Mombeiny, Seyed Reza Moosavi, Javid Amini, Lobat Tayebi

School of Dentistry Faculty Research and Publications

Fabrication of appropriate electro-conductive scaffold, application of small molecules (SMs), electrical stimulation (ES), and stem cells are steps forward in cardiac tissue engineering. Herein, for the first time, all mentioned factors have been taken into account concurrently regarding the differentiation of unrestricted somatic stem cells (USSCs) into cardiac cells. To accomplish this goal, electrospun composite scaffolds made of chitosan (CS) and polyvinyl alcohol (PVA) with multi-wall carbon nanotubes (MWCNTs; ranged from 0 to 2.5% w/w) were fabricated. After analyzing mechanical, electrical, and biological properties, the best MWCNTs portion was selected. Of note, the addition of 2%w/w MWCNTs to the CS/PVA …

Carbon Nanotube-Coated Scaffolds For Tissue Engineering Applications, Soham Dipakbhai Parikh

Browse all Theses and Dissertations

Carbon Nanotubes (CNTs) have beneficial properties for cell scaffolding, which has translated into effective growth of bone, muscle, and cardiac cells. However, loose carbon nanotubes can cause in vivo toxicity. To reduce this risk, our team has developed biomimetic scaffolds with multiscale hierarchy where carpet-like CNT arrays are covalently bonded to larger biocompatible substrates. In this study, we have tested such scaffolds in two distinct types of biomedical applications involving glioblastoma and keratinocyte cells. The growth of glioblastoma (GBM) cells on our CNT-coated biomimetic scaffolds was evaluated to check their suitability as a potential chemotherapy-loaded implant for GBM patient treatment. …

Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Iii, L. A. Ivanov, L. D. Xu, E. S. Bokova, A. V. Demenev, V. A. Ivanov

Information Technology & Decision Sciences Faculty Publications

Introduction. Advanced technologies impress people’s imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries.

Main part. The article provides an abstract review of patents. The results of creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials, being implemented, allow achieving a significant effect in construction, housing and community services, and related sectors of the economy. For example, the invention «Composite material with oriented carbon nanotubes» refers to the area of …

Development Of Novel Membranes For Nanocarbon Enhanced Separation With Application In Biofuels And Solvent Recover, Oindrila Gupta

Dissertations

Pharmaceutical industries historically have had one of the highest amounts of solvent waste generated per unit of drug manufactured. Energy requirements and carbon footprint of current solvent recycling processes tend to be quite high, and the incineration of the solvents for waste disposal produces toxic air emissions. Also, rapidly increasing demand for energy and strict regulation on engine pollutant emissions have necessitated the use of alcohol as carbon-neutral fuels. Thermal distillation is one of the most common methods for the separation of alcohol-water mixtures. However, its application is limited due to energy requirements and high operating costs, and heating to …

A Review Of Inkjet Printed Graphene And Carbon Nanotubes Based Gas Sensors, Twinkle Pandhi, Ashita Chandnani, Harish Subbaraman, David Estrada

Materials Science and Engineering Faculty Publications and Presentations

Graphene and carbon nanotube (CNT)-based gas/vapor sensors have gained much traction for numerous applications over the last decade due to their excellent sensing performance at ambient conditions. Inkjet printing various forms of graphene (reduced graphene oxide or modified graphene) and CNT (single-wall nanotubes (SWNTs) or multiwall nanotubes (MWNTs)) nanomaterials allows fabrication onto flexible substrates which enable gas sensing applications in flexible electronics. This review focuses on their recent developments and provides an overview of the state-of-the-art in inkjet printing of graphene and CNT based sensors targeting gases, such as NO₂, Cl₂, CO₂, NH_{3 …}

3d Interdigitated Vertically Aligned Carbon Nanotube Electrodes For Electrochemical Impedimetric Biosensing, Benjamin J. Brownlee, Jonathan C. Claussen, Brian D. Iverson

Faculty Publications

Advances in nanomaterials, combined with electrochemical impedance spectroscopy (EIS), have allowed electrochemical biosensors to have high sensitivity while remaining labe-lfree, enabling the potential for portable diagnosis at the point-of-care. We report porous, 3D vertically aligned carbon nanotube (VACNT) electrodes with underlying chromium electrical leads for impedance-based biosensing. The electrodes are characterized by electrode height (5, 25, and 80 μm), gap width (15 and 25 μm), and geometry (interdigitated and serpentine) using scanning electron microscopy, cyclic voltammetry, and EIS. The protein streptavidin is functionalized onto VACNT electrodes for detection of biotin, as confirmed by fluorescence microscopy. EIS is used to measure …

All-Carbon Conductors For Electronic And Electrical Wiring Applications, Federico Cesano, M. Jasim Uddin, Karen Lozano, Marco Zanetti, Domenica Scarano

Chemistry Faculty Publications and Presentations

Electrical conductors based on carbons have recently attracted a growing interest due to the prospect of replacing metals. Electrical conductors without metals could represent not only an alternative for traditional wiring, but also a step forward in the progress and advancing of technology. This result can be achieved by combining high electrical conductivity with other properties, that are dexterity, light weight, environmental stability, high strength and flexibility. As the best mechanical properties, high electrical/thermal conductivity of the assembled fibers are all generally associated with low concentration of defects in the fiber backbone and in the individual carbon “building blocks”, a …

Pressure Driven Desalination Utilizing Nanomaterials, Fangyou Xie

Master's Theses

Nanomaterials such as graphene oxide and carbon nanotubes, have demonstrated excellent properties for membrane desalination, including decrease of maintenance, increase of flux rate, simple solution casting, and impressive chemical inertness. Here, two projects are studied to investigate nanocarbon based membrane desalination. The first project is to prepare hybrid membranes with amyloid fibrils intercalated with graphene oxide sheets. The addition of protein amyloid fibrils expands the interlayer spacing between graphene oxide nanosheets and introduces additional functional groups in the diffusion pathways, resulting in increase of flux rate and rejection rate for the organic dyes. Amyloid fibrils also provide structural assistance to …

Fabrication And Application Of Flexible Sensors, Tallis Huther Da Costa

LSU Doctoral Dissertations

A transfer printing method was developed to transfer carbon nanotubes (CNTs) from polyethylene terephthalate (PET) film to poly(dimethyl siloxane) (PDMS) polymer. Carbon nanotubes are composed of carbon atoms arranged in a honeycomb lattice structure, which are electrically conducting. When embedded in a nonconducting polymer, carbon nanotubes impart electrical conductivity to the nanocomposite, thus forming a nanocomposite that has potential applications in highly sensitive strain and pressure sensors. Several printing methods have been studied to deposit carbon nanotubes onto PDMS, including inkjet printing. Inkjet printing is a desirable deposition method since it is low-cost, simple, and allows the processing of aqueous-based …

Electrical Performance Retention Of Doped Carbon Nanotube Conductors For High Current Applications, Karen J. Soule

Theses

Carbon nanotube (CNT) wires are light-weight and robust alternatives to conventional metal conductors. The weight savings, increased flexure tolerance, and corrosion resistance of CNT conductors make them a viable solution for a variety of space, defense, and power transmission applications. An individual CNT has orders of magnitude greater electrical conductivity than conventional metal conductors, but this has not been realized in bulk CNT networks. Recently, the use of chemical dopants has resulted in bulk CNT wire conductivities approaching 10 MS/m. As the electrical conductivity of CNT wires continues to approach that of conventional metals, deployment of CNT conductors will require …

Electrochemical Sensors Enhanced By Convection And By 3d Arrays Of Vertically Aligned Carbon Nanotubes, Benjamin James Brownlee

Theses and Dissertations

Early and accessible diagnostics are important elements to reducing the negative side-effects of untreated disease. One key advancement in diagnostic monitoring is through the development of highly sensitive sensors that have the capability to detect lower concentrations, while still remaining accessible for point-of-care use. This dissertation characterizes electrochemical sensing platforms that are enhanced by convection and by 3D electrodes made from high surface area, vertically aligned carbon nanotubes (VACNTs). Free-standing VACNTs were patterned into microchannel arrays for flow-through amperometric sensing. Convective mass transfer enhancement was shown to improve sensor performance in amperometric sensing through the use of high surface area …

Investigation Of Glucose Oxidation At Gold Nanoparticles Deposited At Carbon Nanotubes Modified Glassy Carbon Electrode By Theoretical And Experimental Methods., Farhat Saira, Humaira Razzaq, Misbah Mumtaz, Safeer Ahmad, Muhammad Aftab Rafiq, Azra Yaqub, Nabiha Dilshad, Ayesha Ihsan, Muhammad Masood Ul Hasan

Karbala International Journal of Modern Science

In the current research work, AuNPs-CNTs nanocomposite was synthesized chemically and decoration of AuNPs on the surface of MWCNTs was confirmed by UV-Vis, SEM and XPS analysis. Synthesized nanocomposite was utilized for its application towards non-enzymatic glucose sensing by modifying glassy carbon electrode with nanocomposite employing electrochemical techniques. In addition, theoretical calculations were performed by Density Functional Theory (DFT), employing B3YLP with basis set 6- 311+G(d,p) in gaseous phase and LANL2DZ basis set. Both theoretical and experimental results predicted Au-CNTs composite as a better candidate for glucose oxidation as compared to CNTs and AuNPs alone, owing to the synergistic effect …

Composite Gel Polymer Electrolytes For Extended Cyclability Of Lithium-Oxygen Batteries, Marcus Carlton Herndon

FIU Electronic Theses and Dissertations

In lithium-oxygen (Li-O₂) batteries, addressing challenges like electrode degradation, cell stability and electrolyte decomposition are key to creating more practical applications. Despite many attempts to minimize anode oxidation and cathode byproduct formation, the electrolyte remains the leading source for rapid capacity fading and poor cyclability in Li-O₂batteries. Understanding the loss of functionality in electrolytes, carbon nanotube (CNT) fillers and redox mediators (RM), during cycling within Li-O₂battery systems, could be the solution to prolonging battery lifetime. Determining the efficiency of these battery components and additives will push the medium towards lifelong, rechargeable and safe battery …

Enhanced Fatigue And Durability Of Carbon Black/Natural Rubber Composites Reinforced With Graphene Oxide And Carbon Nanotubes, Hao Guo, Stephen Jerrams, Zongchao Xu, Yanfen Shou, Liang Jiang, Liqun Zhang, Li Liu, Shipeng Wen

Articles

Graphene oxide (GO) sheets and carbon nanotubes (CNTs) are of nanometer size and offer large shape factors which are beneficial in reducing crack propagation rates of composites when used in carbon black (CB) reinforced natural rubber (NR), thereby prolonging the service lives of rubber composites. In this research, CNT-CB/NR and GO-CB/NR composites were prepared by partially replacing CB with one-dimensional CNTs and two-dimensional flaky graphene oxide GO, respectively. The results showed that the complex filler dispersion in NR matrices was improved due to the isolation effect between the different fillers. The strain-induced crystallization (SIC) ability of CB/NR was effectively enhanced …

Gas Adsorption In Carbon Nanohorns: Equilibrium And Kinetics, Justin Matthew Petucci

Electronic Theses and Dissertations

A study of gas adsorption has been carried out with the focus of better understanding the relationships between the individual properties of the adsorbent/adsorbate (e.g. material structure, interactions, gas size and shape, etc.) and the overall adsorptive properties of the combined system (e.g. capacity, binding strength, equilibration time, etc.) as a function of thermodynamical variables. This is useful from the perspective of a comprehensive and fundamental understanding as well as for practical applications. The equilibrium regime of adsorption on carbon nanostructure materials (nanohorns, nanotubes, and graphite) is investigated using molecular statics (MS) and grand canonical monte carlo (GCMC) methods for …

Fabrication, Development, And Characterization Of Hipco Swcnt - Alginate Hydrogel Composites For Cellular Product Applications, Fabian Armando Alvarez-Primo

Open Access Theses & Dissertations

In this study, we designed, synthesized, and characterized ultrahigh purity single-walled carbon nanotube (SWCNT)-alginate hydrogel composites. Among the parameters of importance in the formation of an alginate-based hydrogel composite with single-walled carbon nanotubes, are their varying degrees of purity, their particulate agglomeration and their dose-dependent correlation to cell viability, all of which have an impact on the resultant compositeâ??s efficiency and effectiveness towards biomedical applications. To promote their homogenous dispersion by preventing agglomeration of the SWCNT, at first, we used three different surfactants-sodium dodecyl sulfate (SDS-anionic), cetyltrimethylammonium bromide (CTAB-cationic), and Pluronic F108 (nonionic). After experimentation and corroboration through evidence obtained …

Numerical Analysis Of Carbon Nanotube-Based Nanofluid Unsteady Flow Amid Two Rotating Disks With Hall Current Coatings And Homogeneous-Heterogeneous Reactions, Muhammad Ramzan, Saima Riasat, Seifedine Kadry, Pin Kuntha, Yunyoung Nam, Fares Howari

All Works

© 2020 by the authors. In the present exploration, our objective is to investigate the importance of Hall current coatings in the establishment of Cattaneo-Christov (CC) heat flux model in an unsteady aqueous-based nanofluid flow comprising single (SWCNTs) and multi-walled (MWCNTs) carbon nanotubes (CNTs) amid two parallel rotating stretchable disks. The novelty of the presented model is strengthened with the presence of homogeneous-heterogeneous (HH) reactions and thermal stratification effects. The numerical solution of the system of coupled differential equations with high nonlinearity is obtained by applying the bvp4c function of MATLAB software. To corroborate the authenticity of the present envisioned …

Stepwise Reduction Of Non-Planar Molecular Nanocarbons : From Functionalized Bowls To Helicenes And Nanohoops, Zheng Zhou

Legacy Theses & Dissertations (2009 - 2024)

Molecular nanocarbons, which can be considered as fragments of fullerenes, carbon nanotubes, or graphene, have stimulated the rapid development of carbon chemistry at the molecular level in recent decades. Molecular nanocarbons possess not only outstanding chemical and physical properties stemming from their parent carbon allotropes, but also present such unique features as controllable and scalable synthetic conditions, defined molecular compositions, uniform size, and relatively good solubility. These advances of molecular nanocarbons over conventional carbonaceous materials give rise to the development of such applications as electron transfer, energy transport and storage. However, future progress of these technologically-important fields requires a superior …

Metal Filled Carbon Nanotubes In Radiation Therapy : Dose Enhancement Effect, Sarah Ashmeg

Legacy Theses & Dissertations (2009 - 2024)

In this work, the radiation dose enhancement is studied using a novel method and material that has not been widely investigated, at the time of this publication. Radiation dose enhancement is a useful technique in the field of radiation therapy, especially when dealing with radioresistant cells. Ideally, it increases the dose to the desired site with no additional damage to organs at risk.

Hierarchical Hybrid Materials From Flexible Fabric Substrates, Wenhu Wang

Browse all Theses and Dissertations

The goal of this project is to investigate fabrication approaches and structure-property relationships of porous and flexible hierarchical hybrid solids suitable for advanced surface-active devices. Multi-scale hierarchical carbon materials are being fabricated by strong covalent attachment of multiwall carbon nanotube(MWCNTs) arrays on flexible carbon fabric substrates in order to enhance the surface area per unit volume. This was done using chemical vapor deposition (CVD) after functionalizing the surface with a plasma-derived nano-oxide coating. Structural and chemical characterization is performed using scanning electron microscope(SEM), energy dispersive spectroscopy(EDS) and x-ray photoelectron spectroscopy(XPS). Surface area estimates have been made by building structural models …

Electrical Conductivity Of The Aluminum Oxide Diffusion Barrier Following Catalytic Carbon Nanotube Growth, Berg Daniel Dodson

Theses and Dissertations

Carbon nanotube templated microfabrication (CNT-M) is a method that allows high-aspect ratio structures to be made for microelectromechanical systems (MEMS) devices. One concern when making monolithic electrical devices using CNT-M is that the aluminum oxide diffusion barrier will create too large of a resistance in the device. However, in developing CNT based MEMS devices, it has been observed that an electrical DC current is capable of transport from a conductive substrate, across the aluminum oxide, and through to the CNT structure grown on top of it. This thesis attempts to determine the mechanisms responsible for current being able to cross …

Advanced Techniques For Carbon Nanotube Templated Microfabrication, Jason Matthew Lund

Theses and Dissertations

Carbon nanotube templated microfabrication (CNT-M) is a term describing a grouping of processes where carbon nanotubes (CNTs) serve a structural role in the fabrication of a material or device. In its basic form, CNT-M is comprised of two steps: produce a template made from carbon nanotubes and infiltrate the porous template with an additional material. Vertically aligned carbon nanotube (VACNT) templates can be grown to heights ranging from microns to millimeters and lithographically patterned to a desired form. Deposition of an existing thin film material onto a CNT template will coat all template surfaces and can produce a near solid …

Mitsui-7, Heat-Treated, And Nitrogen-Doped Multi-Walled Carbon Nanotubes Elicit Genotoxicity In Human Lung Epithelial Cells, Katelyn J. Siegrist, Steven H. Reynolds, Dale W. Porter, Robert R. Mercer, Alison K. Bauer, David Lowry, Lorenzo Cena, Todd A. Stueckle, Michael L. Kashon, John Wiley, Jeffrey L. Salisbury, John Mastovich, Kristin Bunker, Mark Sparrow, Jason S. Lupoi, Aleksandr B. Stefaniak, Michael J. Keane, Shuji Tsuruoka, Mauricio Terrones, Michael Mccawley, Linda M. Sargent

Lorenzo Cena

Background: The unique physicochemical properties of multi-walled carbon nanotubes (MWCNT) have led to many industrial applications. Due to their low density and small size, MWCNT are easily aerosolized in the workplace making respiratory exposures likely in workers. The International Agency for Research on Cancer designated the pristine Mitsui-7 MWCNT (MWCNT-7) as a Group 2B carcinogen, but there was insufficient data to classify all other MWCNT. Previously, MWCNT exposed to high temperature (MWCNT-HT) or synthesized with nitrogen (MWCNT-ND) have been found to elicit attenuated toxicity; however, their genotoxic and carcinogenic potential are not known. Our aim was to measure the genotoxicity …

Mitsui-7, Heat-Treated, And Nitrogen-Doped Multi-Walled Carbon Nanotubes Elicit Genotoxicity In Human Lung Epithelial Cells, Katelyn J. Siegrist, Steven H. Reynolds, Dale W. Porter, Robert R. Mercer, Alison K. Bauer, David Lowry, Lorenzo Cena, Todd A. Stueckle, Michael L. Kashon, John Wiley, Jeffrey L. Salisbury, John Mastovich, Kristin Bunker, Mark Sparrow, Jason S. Lupoi, Aleksandr B. Stefaniak, Michael J. Keane, Shuji Tsuruoka, Mauricio Terrones, Michael Mccawley, Linda M. Sargent

Public Health Sciences Faculty Publications

Background: The unique physicochemical properties of multi-walled carbon nanotubes (MWCNT) have led to many industrial applications. Due to their low density and small size, MWCNT are easily aerosolized in the workplace making respiratory exposures likely in workers. The International Agency for Research on Cancer designated the pristine Mitsui-7 MWCNT (MWCNT-7) as a Group 2B carcinogen, but there was insufficient data to classify all other MWCNT. Previously, MWCNT exposed to high temperature (MWCNT-HT) or synthesized with nitrogen (MWCNT-ND) have been found to elicit attenuated toxicity; however, their genotoxic and carcinogenic potential are not known. Our aim was to measure the genotoxicity …

Effects Of Infiltration Temperature, Time, And Gas Flow Rate On Material Properties Of Carbon Infiltration Carbon Nanotubes, Shane Dirk Sypherd

Theses and Dissertations

This work characterizes the material properties of carbon infiltrated carbon nanotube (CI- CNT) structures. The impacts of temperature, time, and hydrogen flow rates on the material prop- erties of modulus of elasticity and strength are examined and compared. Carbon infiltration levels are assessed through the use of SEM images to determine which parameters give the highest level of infiltration. Through the use of SEM, carbon capping is observed on samples infiltrated for longer times at 900 and 950◦ C, suggesting that the samples are not being infiltrated during the entire desired infiltration period at these temperatures. The highest material properties …

Enzymatic Biofuel Cells In A Sandwich Geometry With Compressed Carbon Nanotubes/Enzyme Electrodes & Hybrid Patch Applications, Biao Leng

Dissertations

Enzymatic biofuel cells (EBFCs) convert the chemical energy of biofuels, such as glucose and methanol, into electrical energy by employing enzymes as catalysts. In contrast to conventional fuel cells, EBFCs have a simple membrane-free fuel cell design due to the high catalytic specificity of the enzymes, but the power densities obtained are lower. Although the primary goal of research on EBFCs has been to develop a sustainable power source that can be directly implanted in the human body to power bio-devices, other applications such as the use of a flexible film or fuel cell patch as a wearable power source …

Electrostatically Actuated Double Wall Carbon Nanotubes To Include Intertube Van Der Waals Forces, Ezequiel Juarez Ocanas

Theses and Dissertations

This work deals with the amplitude-frequency and amplitude-voltage responses of parametric and primary resonances of electrostatically actuated double-walled carbon nanotubes (DWCNTs). Nonlinear forces acting on the DWCNT are intertube van der Waals and electrostatic forces. Soft AC excitation and small viscous damping are assumed. In coaxial vibration, the outer and inner carbon nanotubes move together (in-phase), maintaining their geometric concentricity; while in noncoaxial vibration, the CNTs move in opposite direction (out-of-phase). Modal coordinate transformation is formulated. The Harmonic Balance Method (HBM) is used to find the free response solutions of the DWCNT. The Reduced Order Model (ROM) method is also …