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Full-Text Articles in Engineering
Processing And Properties Of Multifunctional Two Dimensional Nanocomposites Based On Graphene Nano-Flakes, Mohammed K. Mohammed
Processing And Properties Of Multifunctional Two Dimensional Nanocomposites Based On Graphene Nano-Flakes, Mohammed K. Mohammed
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The unique properties of graphene have directed researchers to study and characterize this new material. Graphene production and graphene based materials have been widely explored and developed in the past decade. Most research has aimed at developing scalable, environmentally friendly, and cheap procedures to produce defect-free graphene that can be used in various applications such as mechanical properties enhancement and multifunctional material. The challenge is processing such material on a scale suitable for engineering applications such as advanced photonics and advanced electronics. In this study, we investigate a new processing technique based on Langmuir-Blodgett (LB) Technique. We managed to produce …
Chondroitin Sulfate Hydrogels For Total Wound Care Devices, Tushar Goswami
Chondroitin Sulfate Hydrogels For Total Wound Care Devices, Tushar Goswami
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Chondroitin sulfate (CS) is a naturally occurring bio-polymer found in areas of high cartilage in mammals. In directed applications, such as hydrogels, CS can be used to impact keratinocyte growth cycles. In this work, CS based hydrogels were utilized to accelerate wound healing and, in conjunction with a graphene sensor, monitor wound fluid pH. The hydrogels were cast onto a graphene field effect transistor (GFET) to obtain the benefits of the hydrogel wound healing capabilities, while also utilizing the pH sensitivity of the graphene. Results showed that the hydrogel caused a fivefold increase in cell size over the course of …
Exploring Two-Dimensional Graphene And Silicene In Digital And Rf Applications, Zhonghang Ji
Exploring Two-Dimensional Graphene And Silicene In Digital And Rf Applications, Zhonghang Ji
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Since the discovery of graphene, two-dimensional (2D) materials have attracted intensive interests in the past 15 years and there has been a growing interest in exploring new materials beyond graphene, such as silicene, germanene, etc. Numerous papers have been published to demonstrate their extraordinary electronic, optical, biological, and thermal properties which render broad applications in various fields. However, the absence of band gap in graphene and silicene prohibits their uses in digital applications. This dissertation reviews recent progress on band gap opening based on mono- and bi- layer silicene and presents a new silicon atomic structure which exhibits a 0.17 …
A Graphene/Rf Gas Sensor, Kathleen Louise Brockdorf
A Graphene/Rf Gas Sensor, Kathleen Louise Brockdorf
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Toxic chemicals have been used as chemical warfare agents since ancient times, but World War 1 saw the beginning of modern chemical proliferation. There are many methods of detecting these agents, but the combination of high sensitivity, specificity, fast response, and small form factor is difficult to achieve. More recently, graphene has been identified as a possible sensing material for ammonia and other substances. This research documents a novel method of using graphene as a chemical sensor, utilizing a radio-frequency approach to sensing. This approach utilizes all available information from the material, such as permittivity and conductivity, instead of simply …
Deposition Of Nanoparticles Or Thin Films Via Magnetron Sputtering Towards Graphene Surface Functionalization And Device Fabrication, Bridget Jul Larson
Deposition Of Nanoparticles Or Thin Films Via Magnetron Sputtering Towards Graphene Surface Functionalization And Device Fabrication, Bridget Jul Larson
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Graphene, a 2-dimensional single layer of carbon, has high carrier mobility, strength and electrical conductivity. Due to the absence of a band gap and chemical reactivity, pristine graphene has less competitiveness in semiconductors and sensors. Functionalizing graphene is imperative in the development of advanced applications. Among various wet chemical or physical vapor deposition, magnetron sputtering is cost-effective, minimum maintenance, user-friendly, and can be used to rapidly deposit nano-particulates or thin films with less contaminations on any substrates surface. This study is to investigate the morphology evolution of the deposited films using magnetron sputtering and to find appropriate conditions for nanoparticulate …
Thermoelectric Transport And Energy Conversion Using Novel 2d Materials, Luke J. Wirth
Thermoelectric Transport And Energy Conversion Using Novel 2d Materials, Luke J. Wirth
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Nanomaterials hold great promise for applications in thermal management and thermoelectric power generation. Defects in these are important as they are generally inevitably introduced during fabrication or intentionally engineered to control the properties of the nanomaterials. Here, we investigate how phonon-contributed thermal conductance in narrow graphene, boron nitride (BN), and silicene nanoribbons (NRs), responds to the presence of a vacancy defect and the corresponding geometric distortion, from first principles using the non-equilibrium Green's function method. Analyses are made of the geometries, phonon conductance coefficients, and local densities of states (LDOS) of pristine and defected nanoribbons. It is found that hydrogen …
Nano-Materials For Microwave And Terahertz Applications, Joshua Myers
Nano-Materials For Microwave And Terahertz Applications, Joshua Myers
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In this age of digital electronics the quest for faster computational devices and high speed communications have driven a need for new materials that are capable of fulfilling these goals. In both areas the need for a thinner channel in transistors, faster carrier transport characteristics, and better magnetic materials dominate the direction of research. Recently 2D materials have been realized. These single layer atomic thick materials show potential in having extremely high carrier transport velocities at room temperature and, due to their natural 2D structure, are the thinnest material possible in nature. On the other hand spin-spray ferrites have showed …
Synthesis And Characterization Of Graphene Oxide/Sulfur Nanocomposite For Lithium-Ion Batteries, Aaron Joseph Blake
Synthesis And Characterization Of Graphene Oxide/Sulfur Nanocomposite For Lithium-Ion Batteries, Aaron Joseph Blake
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The growing need for clean and efficient energy storage systems has recently peaked due to concerns of climate change and increased global energy consumption. However, efficiently integrating renewable resources such as solar and wind energy into society will require a complex electrical energy storage (EES) system capable of storing and expending significant amounts of energy. A battery based on the lithium/sulfur couple can yield a theoretical specific energy of 2600Wh/kg, which is about five times higher than that offered by present Li-ion batteries, and hence, is a promising and attractive technology. Despite recent developments in addressing various issues inherent to …
Structural And Electronic Properties Of Two-Dimensional Silicene, Graphene, And Related Structures, Ruiping Zhou
Structural And Electronic Properties Of Two-Dimensional Silicene, Graphene, And Related Structures, Ruiping Zhou
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Traditional CMOS (complementary metal-oxide-semiconductor) transistors have already been in the nanometer range. As bulk silicon material is approaching its physical limits, it is highly desirable to seek novel, functional materials to continue Moore's law. Two-dimensional(2D) materials, such as graphene and silicene, have attracted great attention since they were envisioned a few years ago, having extraordinary electrical properties. Research in this work was focused on understanding the structural and electronic properties of a few atomic layers of carbon (graphene) and silicon (silicene). Atomic structures of the 2D materials, corresponding band structures, and transport properties were calculated based on density functional theory. …
Modeling The Exfoliation Rate Of Graphene Nanoplatelet Production And Application For Hydrogen Storage, Cory Knick
Modeling The Exfoliation Rate Of Graphene Nanoplatelet Production And Application For Hydrogen Storage, Cory Knick
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Graphene is a unique and revolutionary new nanomaterial. A method for it's production had a U.S. patent application in 2002 (patent issued in 2006), it was produced via mechanical exfolia-tion in 2004, and subsequently the Nobel Prize in Physics was awarded in 2010 for it. These events have sparked a surge of graphene-related research. In order for graphene to be widely studied and incorporated into emerging technologies, a versatile method for large scale produc-tion of high-quality graphene is required. Current methods are either slow or expensive which limits the scale-up of graphene production. Very recently, the liquid phase exfoliation of …
Graphene Based Rf/Microwave Impedance Sensing And Low Loss Conductor For Rf Applications, Iramnaaz Iramnaaz
Graphene Based Rf/Microwave Impedance Sensing And Low Loss Conductor For Rf Applications, Iramnaaz Iramnaaz
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Biosensors are becoming more popular recently and expanding due to their broad applications in detecting disease and infectious agents, monitoring of environmental toxins, etc. Recognition and quantification of biochemical molecules and molecular interactions present great challenges in biosensing [38]. Impedance sensing at radio frequency (RF) /microwave frequency becomes very attractive as bio-molecules exhibits large distinct dielectric properties, and also because the ionic conductivity of water in most physiological systems is greatly diminished. For example, it has been reported that tumoral cells exhibits large value of electrical conductivity and permittivity which can result in significant variation of the impedance when compared …
Graphene Based Anode Materials For Lithium-Ion Batteries, Sree Lakshmi Cheekati
Graphene Based Anode Materials For Lithium-Ion Batteries, Sree Lakshmi Cheekati
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Improvements of the anode performances in Li-ions batteries are in demand to satisfy applications in transportation. In comparison with graphitic carbons, transition metal oxides as well as graphene can store over twice amount of lithium per gram. Recently, graphene-based anodes for Li-ion batteries are under extensive development. In this research, lithium storage characteristics in graphene oxide (GO), GO/Manganese acetate (GO/MnAc), GO/manganese oxide (GO/MnOx) composites and Nano Graphene Platelets (NGP) were studied. The prepared GO delivered reversible capacities of 706mAh/g with an average columbic efficiency of 87%. Reversible capacities of 533 mAh/g were observed for GO/MnAc composite. GO/MnOx nanocomposite thermal annealed …