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2017

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Articles 481 - 510 of 615

Full-Text Articles in Materials Science and Engineering

Development Of Highly Sensitive And Selective Breathing Sensors Using Molecular Imprinted Filtering For Diabetic And Alcoholic Patients, Md. Saleh Akram Bhuiyan Jan 2017

Development Of Highly Sensitive And Selective Breathing Sensors Using Molecular Imprinted Filtering For Diabetic And Alcoholic Patients, Md. Saleh Akram Bhuiyan

Electronic Theses and Dissertations

Wellness sensor technology is an emerging diagnostic test research field, which mostly deal with the point of care of the patients in the recent days. Due to the lack of awareness from the patients, most diseases cannot be detected in due time. This led to worse conditions, such as diabetic and alcoholic syndrome. Therefore, many research groups have been working to develop portable sensor devices that can track serious diseases. These include diabetic and alcoholic biomarkers in breathing. These devices have very high selectivity and reliability. However, the major limitation of biomarkers is that it deals with the bio-molecular based …


Bio Inspired Lightweight Composite Material Design For 3d Printing, Kaushik Thiyagarajan Jan 2017

Bio Inspired Lightweight Composite Material Design For 3d Printing, Kaushik Thiyagarajan

Electronic Theses and Dissertations

Lightweight material design is an indispensable subject in product design. The lightweight material design has high strength to weight ratio which becomes a huge attraction and an area of exploration for the researchers as its application is wide and increasing even in every day-to-day product. Lightweight composite material design is achieved by selection of the cellular structure and its optimization. Cellular structure is used as it has wide multifunctional properties in addition to the lightweight characteristics. Applications of light weight cellular structures are wide and is witnessed in all industries from aerospace to automotive, construction to product design. In this …


Advanced Carbon Materials Based Electrodes For High Performance Symmetric Supercapacitors, Keliang Wang Jan 2017

Advanced Carbon Materials Based Electrodes For High Performance Symmetric Supercapacitors, Keliang Wang

Electronic Theses and Dissertations

Supercapacitors have received considerable attention due to their high energy density, long life time, rapid charge/discharge rate, and because they are environmental friendly technology. Electrode materials play a key role in the final performance of supercapacitors. Carbon, usually used as symmetric supercapacitors electrode materials, exhibit extraordinary stability in harsh electrolyte and electrochemical performance owing to its physical and chemical properties. In addition, porous structure originated from activation, excellent electrical conductivity, sustainability, wide availability and low cost further offering the improvement in electrochemical performance and make it to be a promising electrode material for symmetric supercapacitors. Considering the factors affected electrochemical …


Activated Carbon Preparation And Modification For Adsorption, Yuhe Cao Jan 2017

Activated Carbon Preparation And Modification For Adsorption, Yuhe Cao

Electronic Theses and Dissertations

Butanol is considered a promising, infrastructure-compatible biofuel. Butanol has a higher energy content than ethanol and can be used in conventional gas engines without modifications. Unfortunately, the fermentation pathway for butanol production is restricted by its toxicity to the microbial strains used in the process. Butanol is toxic to the microbes, and this can slow fermentation rates and reduce butanol yields. Gas stripping technology can efficiently remove butanol from the fermentation broth as it is produced, thereby decreasing its inhibitory effects. Traditional butanol separation heavily depends on the energy intensive distillation method. One of the main issues in acetone-butanol-ethanol fermentation …


Study Of Stability And Thermal Conductivity Of Nanoparticles In Propylene Glycol, Sumit Mahajan Jan 2017

Study Of Stability And Thermal Conductivity Of Nanoparticles In Propylene Glycol, Sumit Mahajan

All Graduate Theses, Dissertations, and Other Capstone Projects

This thesis studied the effects of gravity induced settling, thermophoresis and Brownian motion on the thermal conductivity of the Aluminum Oxide (Al2O3) nanofluids. The base fluid was propylene glycol. The effects were studied by making three samples with volumetric percentages of 0.2 %, 2% and 3% Al2O3 in propylene glycol. Sets of 22 experiments were conducted over time to understand the behavior of settling. All samples were manually mixed each time the experiment was conducted. A Thermtest Transient Plane Source TPS 500S was used to measure the thermal conductivity. Volumetric percentages and diameters of nanoparticle were chosen so that the …


Dynamic Analysis For Characterization Of Novel Biomass Based Composities, Aarsh Jigish Shah Jan 2017

Dynamic Analysis For Characterization Of Novel Biomass Based Composities, Aarsh Jigish Shah

Electronic Theses and Dissertations

Resources from forests constitute a significant asset of Mississippi State. Forests cover around 19.7 million acres (65%) of the total land area of Mississippi. Total annual economic impact of Mississippi’s forest products is about $17 billion. Creation of high-value products will lead to a number of economic benefits to the region. This work focuses on the study of bio-composite. Bio-composite materials are a ‘Green’ alternative to conventional materials which are readily recyclable and biodegradable. Taylor made properties are achievable in bio-composites, this being one of the significant advantages. Producing biodegradable products has become a necessity due to petroleum-based products being …


Compact Facility For Testing Steady And Transient Thermal Performance Of Building Walls, Aimee Byrne, Gerard Byrne, Anthony Robinson Jan 2017

Compact Facility For Testing Steady And Transient Thermal Performance Of Building Walls, Aimee Byrne, Gerard Byrne, Anthony Robinson

Articles

Energy efficiency retrofit of buildings represents a key effort in reducing EU energy demand by 20% by 2020. However, predictions tend to overestimate savings by large percentages. The shortfall in savings can be attributed to incorrect predictive techniques, comfort takeback along with other behavioural and workmanship variables. Common predictive techniques related to heat loss tend to be based on the U-value of the building envelope. This paper presents the design of a more straightforward and compact version of the traditional Hot-Box apparatus (measures U-value) which instead determines the thermal resistance of samples of building envelope. U-value includes the need to …


Engineering Of Organic Nanocrystals By Electrocrystallization, Mohamed Kilani Jan 2017

Engineering Of Organic Nanocrystals By Electrocrystallization, Mohamed Kilani

Wayne State University Theses

This work discusses the experimental and theoretical methods used to control the morphology of nanocrystals. The hypothesis of the thermodynamic/kinetic control of the morphology was verified. We applied the electrocrystallization to make K(def)TCP nanocrystals and we tuned the electrochemical parameters to determine their influence on the nanocrystals morphologies. The characterization was mainly performed with AFM and FE-SEM. We presented in this work the possibility to control the morphology of K(def)TCP using the electrochemical parameters. The obtained shapes ranged from nanorods to rhombohedral shape, which is reported for the first time. The observed growth behavior was modeled and simulated with a …


Application Of Phase Shifting Electronic Speckle Pattern Interferometry In Studies Of Photoinduced Shrinkage Of Photopolymer Layers, Mohesh Moothanchery, Viswanath Bavigadda, Manojit Pramanik, Vincent Toal, Izabela Naydenova Jan 2017

Application Of Phase Shifting Electronic Speckle Pattern Interferometry In Studies Of Photoinduced Shrinkage Of Photopolymer Layers, Mohesh Moothanchery, Viswanath Bavigadda, Manojit Pramanik, Vincent Toal, Izabela Naydenova

Articles

Photoinduced shrinkage occurring in photopolymer layers during holographic recording was determined by Phase Shifting Electronic Speckle Pattern Interferometry. Phase maps were calculated from the changes in intensity at each pixel due to the phase differences introduced between object and reference beams. Shrinkage was then obtained from the changes in phase as recording proceeded. The technique allows for whole field measurement of the dimensional changes in photopolymers during holographic recording.


Engineering Crystallization Via Phase Field Crystal Model, Deepak Joshi Jan 2017

Engineering Crystallization Via Phase Field Crystal Model, Deepak Joshi

Wayne State University Theses

Charge transfer complex material demonstrate morphological transitions while electro-crystallized on a substrate electrode under varying solute concentration and applied overpotential. It is hypothesized that variations in these parameters affect the thermodynamics and the kinetics of the electro-crystallization process. Having analysed these results, we resort to applying phase field crystal(PFC) model for our theoretical study. Our initial literature review laid foundation to consider PFC model as a powerful tool to study various aspect of crystallization process. In a PFC model the thermodynamic state of a system under study is defined in terms of Helmholtz free energy functional of density profile F=F[ρ(r)].Our …


Materials For Giant Spin Hall Effect Devices, Avyaya Jayanthinarasimham Jan 2017

Materials For Giant Spin Hall Effect Devices, Avyaya Jayanthinarasimham

Legacy Theses & Dissertations (2009 - 2024)

Studies presented in this thesis are an effort to control the growth of β W and explore


Development Of Multilayer Titanium Nitride-Based Coatings As Corrosion Resistant Films For Stainless Steel Bipolar Plates In Pem Fuel Cells, Nicholas Padula Jan 2017

Development Of Multilayer Titanium Nitride-Based Coatings As Corrosion Resistant Films For Stainless Steel Bipolar Plates In Pem Fuel Cells, Nicholas Padula

Legacy Theses & Dissertations (2009 - 2024)

High cost and short lifetime are the two main reasons why the PEM fuel cell has not reached a widespread, disruptive level of commercialization. Conventional graphite bipolar plates are responsible for about 45% of the cost and 85% of the total weight of a single cell. These measures are linked to difficult machining of thick, brittle graphite and processing needed to render graphite non-porous. Stainless steel is suggested as the replacement bipolar plate material due to its favorable mechanical properties, ease of manufacturing and relatively low price, but requires a cost-effective coating as a non-conductive oxide forms on the bare …


Elucidation And Optimization Of Resistive Random Access Memory Switching Behavior For Advanced Computing Applications, Zahiruddin Alamgir Jan 2017

Elucidation And Optimization Of Resistive Random Access Memory Switching Behavior For Advanced Computing Applications, Zahiruddin Alamgir

Legacy Theses & Dissertations (2009 - 2024)

RRAM has recently emerged as a strong candidate for non-volatile memory (NVM). Beyond memory applications, RRAM holds promise for use in performing logic functions, mimicking neuromorphic activities, enabling multi-level switching, and as one of the key elements of hardware based encryption or signal processing systems. It has been shown previously that RRAM resistance levels can be changed by adjusting compliance current or voltage level. This characteristic makes RRAM suitable for use in setting the synaptic weight in neuromorphic computing circuits. RRAM is also considered as a key element in hardware encryption systems, to produce unique and reproducible signals. However, a …


Computational Optimization And Characterization Of Molecularly Imprinted Polymers, Jacob Jordan Terracina Jan 2017

Computational Optimization And Characterization Of Molecularly Imprinted Polymers, Jacob Jordan Terracina

Legacy Theses & Dissertations (2009 - 2024)

Molecularly imprinted polymers (MIPs) are a class of materials containing sites capable of selectively binding to the imprinted target molecule. Computational chemistry techniques were used to study the effect of different fabrication parameters (the monomer-to-target ratios, pre-polymerization solvent, temperature, and pH) on the formation of the MIP binding sites. Imprinted binding sites were built in silico for the purposes of better characterizing the receptor – ligand interactions. Chiefly, the sites were characterized with respect to their selectivities and the heterogeneity between sites.


Exploring Magnetic Nanostructures Embedded Within Single-Crystal Silicon For Generation Of Spin-Polarized Carriers, Machara Krishna Girish Malladi Jan 2017

Exploring Magnetic Nanostructures Embedded Within Single-Crystal Silicon For Generation Of Spin-Polarized Carriers, Machara Krishna Girish Malladi

Legacy Theses & Dissertations (2009 - 2024)

Integrating magnetic functionalities with silicon holds the promise of developing, in the most dominant semiconductor, a paradigm-shift information technology based on the manipulation and control of electron spin and charge. Here, we demonstrate an ion implantation approach enabling the synthesis of a ferromagnetic layer within a defect free Si environment by exploiting an additional implant of hydrogen in a region deep below the metal implanted layer. Upon post-implantation annealing, nanocavities created within the H-implanted region act as trapping sites for gettering the implanted metal species, resulting in the formation of metal nanoparticles in a Si region of excellent crystal quality. …


Homo- And Heterometallic Bis(Pentafluorobenzoyl)Methanide Complexes Of Copper(Ii) And Cobalt(Ii), Janell Crowder Jan 2017

Homo- And Heterometallic Bis(Pentafluorobenzoyl)Methanide Complexes Of Copper(Ii) And Cobalt(Ii), Janell Crowder

Legacy Theses & Dissertations (2009 - 2024)

β-Diketones are well known to form metal complexes with practically every known metal and metalloid. Metal complexes of fluorinated β-diketones generally exhibit increased volatility and thermal stability compared to the non-fluorinated analogues, and thus are used extensively in various chemical vapor deposition (CVD) processes for the deposition of metal, simple or mixed metal oxides, and fluorine-doped metal oxide thin films. Furthermore, the electron-withdrawing nature of the fluorinated ligand enhances the Lewis acidity of a coordinatively unsaturated metal center which facilitates additional coordination reactions. The physical and structural properties of fluorinated β-diketonate complexes are discussed in Chapter 1 …


Effect Of Ion Flux (Dose Rate) In Source-Drain Extension Ion Implantation For 10-Nm Node Finfet And Beyond On 300/450mm Platforms, Ming-Yi Shen Jan 2017

Effect Of Ion Flux (Dose Rate) In Source-Drain Extension Ion Implantation For 10-Nm Node Finfet And Beyond On 300/450mm Platforms, Ming-Yi Shen

Legacy Theses & Dissertations (2009 - 2024)

The improvement of wafer equipment productivity has been a continuous effort of the semiconductor industry. Higher productivity implies lower product price, which economically drives more demand from the market. This is desired by the semiconductor manufacturing industry. By raising the ion beam current of the ion implanter for 300/450mm platforms, it is possible to increase the throughput of the ion implanter. The resulting dose rate can be comparable to the performance of conventional ion implanters or higher, depending on beam current and beam size. Thus, effects caused by higher dose rate must be investigated further. One of the major applications …


Modeling And Studying The Effect Of Texture And Elastic Anisotropy Of Copper Microstructure In Nanoscale Interconnects On Reliability In Integrated Circuits, Adarsh Basavalingappa Jan 2017

Modeling And Studying The Effect Of Texture And Elastic Anisotropy Of Copper Microstructure In Nanoscale Interconnects On Reliability In Integrated Circuits, Adarsh Basavalingappa

Legacy Theses & Dissertations (2009 - 2024)

Copper interconnects are typically polycrystalline and follow a lognormal grain size distribution. Polycrystalline copper interconnect microstructures with a lognormal grain size distribution were obtained with a Voronoi tessellation approach. The interconnect structures thus obtained were used to study grain growth mechanisms, grain boundary scattering, scattering dependent resistance of interconnects, stress evolution, vacancy migration, reliability life times, impact of orientation dependent anisotropy on various mechanisms, etc. In this work, the microstructures were used to study the impact of microstructure and elastic anisotropy of copper on thermal and electromigration induced failure.


Nonlinear Dielectric Behavior Of Field-Induced Antiferroelectric/Paraelectric-To-Ferroelectric Phase Transition For High Energy Density Capacitor Application, Mingyang Li Jan 2017

Nonlinear Dielectric Behavior Of Field-Induced Antiferroelectric/Paraelectric-To-Ferroelectric Phase Transition For High Energy Density Capacitor Application, Mingyang Li

Dissertations, Master's Theses and Master's Reports

Electric field-induced antiferroelectric(AFE)/paraelectric(PE)-to-ferroelectric(FE) phase transitions are investigated for the associated nonlinear dielectric behavior, which could offer high dielectric capacity. The phenomenon in monolithic materials has been computed for Kittel antiferroelectric and BaTiO3 model systems using the Landau-Ginzburg-Devonshire theory. The general switching curves give values of the polarization as a function of external electric field. A similar computation is performed for particle-filled polymer-matrix composites where an internal depolarization field is considered. The polarization-electric field response changes with different depolarization factors, which demonstrate the shape and alignment of the dielectric particles embedded in polymer-matrix are key factors for the composite to …


Phase Stability In Cobalt-Based L12 Quaternary Intermetallics From Density Functional Theory, William Earwood Jan 2017

Phase Stability In Cobalt-Based L12 Quaternary Intermetallics From Density Functional Theory, William Earwood

Electronic Theses and Dissertations

The effects of higher order alloying additions (Mo, Ti, Ta, Hf, Fe, V) on the phase stability of L12 (γ’) intermetallics have been studied via first-principles. A 32 atom special-quasi-random structure was used to mimic the experimentally observed solid solution sublattice. Density of states distributions were generated in order to directly observe the impact of alloying additions on the position of the pseudogap and number of states at the Fermi level. Charge density differences across the supercell were visualized to analyze changes in bonding behavior. The results indicate that substitutions of Ti, Ta, and Hf in place of the central …


Band Gap Engineering Of Titania Systems Purposed For Photocatalytic Activity, Cameron Robert Thurston Jan 2017

Band Gap Engineering Of Titania Systems Purposed For Photocatalytic Activity, Cameron Robert Thurston

Electronic Theses and Dissertations

Ab initio computer aided design drastically increases candidate population for highly specified material discovery and selection. These simulations, carried out through a first-principles computational approach, accurately extrapolate material properties and behavior. Titanium dioxide (tio2) is one such material that stands to gain a great deal from the use of these simulations. In its anatase form, titania (tio2) has been found to exhibit a band gap nearing 3.2 ev. If titania is to become a viable alternative to other contemporary photoactive materials exhibiting band gaps better suited for the solar spectrum, then the band gap must be subsequently reduced. To lower …


Biomaterials Approaches For Utilizing The Regenerative Potential Of The Peripheral Nerve Injury Microenvironment, Melissa Renee Wrobel Jan 2017

Biomaterials Approaches For Utilizing The Regenerative Potential Of The Peripheral Nerve Injury Microenvironment, Melissa Renee Wrobel

Wayne State University Dissertations

Clinically available treatments are insufficient to achieve full functional recovery in large (>3cm) peripheral nerve injuries (PNI). The objectives in this thesis were 1) to study often overlooked elements of intrinsic PNI repair including release of inhibitory CSPGs and post-injury responses of inflammatory macrophages and dedifferentiated Schwann cells; 2) to create biomaterial scaf-folds featuring topographical and adhesive cues to enhance neurite outgrowth; and 3) to test the ability of those cues to direct macrophages and Schwann cells towards a pro-regenerative phe-notype. It is hypothesized that recapitulating the positive and negative cues of the PNI microenvi-ronment can better improve regeneration. …


Thermal Analysis Of 3d Printed 420 Stainless Steel, Adithya Pothuri Jan 2017

Thermal Analysis Of 3d Printed 420 Stainless Steel, Adithya Pothuri

All Graduate Theses, Dissertations, and Other Capstone Projects

Additive manufacturing opens new possibilities in the manufacturing industry. 3D printing is a form of additive manufacturing. 3D printers will have a significant influence over the industrial market, with extremely positive effects in no time. The main aim of this research is to determine the effect of process parameters of Binder Jet manufactured 420 Stainless Steel (420SS) parts on thermal properties such as thermal conductivity. Different parameters, such as layer thickness, sintering time and sintering temperature were varied. A full factorial design of experiment matrix was made by varying these parameters using two levels. Testing showed that different parameters affected …


Quality Assessment Of Adhesive Bond Based On Dielectric Properties, Muthu Ram Prabhu Elenchezhian, Vamsee Vadlamudi, Priyanshu Kumar Banerjee, Chaitanya Dave, Anik Mahmood, Rassel Raihan Jan 2017

Quality Assessment Of Adhesive Bond Based On Dielectric Properties, Muthu Ram Prabhu Elenchezhian, Vamsee Vadlamudi, Priyanshu Kumar Banerjee, Chaitanya Dave, Anik Mahmood, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)-Archive

Composite materials are widely used in Aerospace, Marine and Automotive structures to reduce weight and increase performance. Adhesive bonding improves the stress distribution between the composite materials / dissimilar materials and ensures a lighter structure than conventional fastener joints. But still there is not much research on the Non-Destructive strength estimation and life prediction, or the damage prognosis of the adhesive bond. One of the main problems when using adhesive bonding is a "kissing bond" which is a weak adhesion bond alternatively called zero volume disbond. Typically, convectional non-destructive methods cannot detect this kissing bond. Broadband Dielectric Spectroscopy, BbDS, is …


Carbon Nanotube (Cnt) Metallic Composite With Focus On Processing And The Resultant Properties, Md Muktadir Billah Jan 2017

Carbon Nanotube (Cnt) Metallic Composite With Focus On Processing And The Resultant Properties, Md Muktadir Billah

Electronic Theses and Dissertations

Metal-carbon nanotubes (CNTs) composites are the promising advanced materials that are being developed to take the advantage of the exceptional properties of CNTs. Because of the intrinsically strong in-plane atomic SP2 bonding CNTs offer high young's modulus (1.0–1.8 TPa), high tensile strength (30–200 GPa) and high elongation at break (10–30%). The thermal conductivity of individual single-walled carbon nanotube (SWCNT) and multi-walled carbon nanotube (MWCNT) are about 6000 W/m-K and 3000 W/m-K, respectively. Therefore it is expected that by incorporation of CNTs in metal matrices multi-functional composites can be used ideally as thermal interface materials, light-weight high-strength structural materials, electric components, …


Enhanced Handheld Engine Ethanol Study, Charindu Kariyawasan Jalath Thanthree Jan 2017

Enhanced Handheld Engine Ethanol Study, Charindu Kariyawasan Jalath Thanthree

All Graduate Theses, Dissertations, and Other Capstone Projects

This study examined consumer and professional grade handheld engines. Twenty-four consumer grade 50 hour Emissions Determination Period (EDP) trimmers and 24 professional grade 300 hour EDP backpack leaf blowers were run on four different ethanol fuel concentrations; E0, E10, E15, and E20. Six engines of each type were run on each of the fuel blends through their full EDP.

All engines were broken-in and adjusted to manufacturer specifications on E0. Then engines were emissions tested on E0 to provide a baseline and to determine the rich to lean order of the engines. Next, the leanest operating engine received E20 and …


Synthesis And Characterization Of Poly(Simvastatin) - Incorporated Copolymers And Blends For Bone Regeneration, Theodora Asafo-Adjei Jan 2017

Synthesis And Characterization Of Poly(Simvastatin) - Incorporated Copolymers And Blends For Bone Regeneration, Theodora Asafo-Adjei

Theses and Dissertations--Biomedical Engineering

Common biodegradable polyesters such as poly(lactic acid) (PLA), poly(lactic-co-glycolic acid) (PLGA) and poly(ε-caprolactone) (PCL) are used as drug delivery vehicles for tissue regenerative applications. However, they are typically bioinert, with drug loading limitations. Polymerizing the active agent or precursor into its respective biodegradable polymer would control drug loading via molar ratios of drug to initiator used for synthesis. Simvastatin was chosen due to its favorable anti-inflammatory, angiogenic, and osteogenic properties. In addition, its lactone ring lends itself to ring-opening polymerization and, consequently, the synthesis of poly(simvastatin) with controlled simvastatin release.

Simvastatin was first polymerized with a 5kDa methyl-terminated poly(ethylene glycol) …


Tunable Nanocomposite Membranes For Water Remediation And Separations, Sebastián Hernández Sierra Jan 2017

Tunable Nanocomposite Membranes For Water Remediation And Separations, Sebastián Hernández Sierra

Theses and Dissertations--Chemical and Materials Engineering

Nano-structured material fabrication using functionalized membranes with polyelectrolytes is a promising research field for water pollution, catalytic and mining applications. These responsive polymers react to external stimuli like temperature, pH, radiation, ionic strength or chemical composition. Such nanomaterials provide novel hybrid properties and can also be self-supported in addition to the membranes.

Polyelectrolytes (as hydrogels) have pH responsiveness. The hydrogel moieties gain or lose protons based on the pH, displaying swelling properties. These responsive materials can be exploited to synthesize metal nanoparticles in situ using their functional groups, or to immobilize other polyelectrolytes and biomolecules. Due to their properties, these …


Effect Of Interlayers On Mechanical Properties And Interfacial Stress Transfer Of 2d Layered Graphene-Polymer Nanocompsites, Colton C. Roach Jan 2017

Effect Of Interlayers On Mechanical Properties And Interfacial Stress Transfer Of 2d Layered Graphene-Polymer Nanocompsites, Colton C. Roach

Theses and Dissertations--Mechanical and Aerospace Engineering

Graphene, a monolayer of sp2-hybridized carbon atoms arranged in a two-dimensional (2D) lattice, is one of the most important 2D nanomaterials and has attracted tremendous attentions due to its unique geometric characteristics and exceptional mechanical properties. One of the most promising applications of this 2D nanomaterial is in polymer nanocomposites, in which the ultra-stiff, ultra-thin graphene layers function as reinforcement fillers. However, two significant questions remain to be answered: (1) whether the mechanical behaviors of 2D graphene reinforced nanocomposites can be analyzed by the convention composite theory, which is developed primarily for one-dimensional (1D) fiber-type of fillers, and …


The Limits & Effects Of Draw On Properties And Morphology Of Pan-Based Precursor And The Resultant Carbon Fibers, Sarah Edrington Jan 2017

The Limits & Effects Of Draw On Properties And Morphology Of Pan-Based Precursor And The Resultant Carbon Fibers, Sarah Edrington

Theses and Dissertations--Mechanical and Aerospace Engineering

The process, structure, and property relationship of PAN fiber as a precursor to carbon fiber was studied. The limitations of stable spinning and property improvement associated with hot draw in solution spinning were found and quantified. Conditions were varied to generated precursor fiber up to the limit of draw, from which actual samples were collected for thermal conversion to carbon fiber. Samples of PAN and subsequent carbon fiber were characterized using tensile testing and x-ray analysis. The effects of draw on modulus and break stress, as well as the orientation of the crystalline structure of both parent precursor and resultant …