Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration,
2019
University of Connecticut
Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi S. Patel
University Scholar Projects
Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.
Objective: Here, we establish a biodegradable, piezoelectric …
Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration,
2019
University of Connecticut
Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi Patel
Honors Scholar Theses
Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.
Objective: Here, we establish a biodegradable, piezoelectric …
Systems Analysis For Pet And Olefin Polymers In A Circular Economy,
2019
Michigan Technological University
Systems Analysis For Pet And Olefin Polymers In A Circular Economy, David R. Shonnard, Emily Tipaldo, Vicki Thompson, Joshua M. Pearce, Gerard T. Caneba, Robert Handler
Michigan Tech Publications, Part 1
Polyethylene terephthalate (PET #1) and polyolefin plastics such polyethylene (HDPE #2, LDPE #4) and polypropylene (PP #5) are major products from the chemical industry, and they comprise a significant fraction of municipal solid waste that ends up in landfills or as litter and marine debris. The reuse of these polymeric materials can be optimized through systems analysis with a view on materials flow analysis, techno-economics, environmental life cycle assessment, and consequential societal impacts. This contribution will present the overall research approach for this exploratory project within the DOE- and industry-funded REMADE Institute and end with a proposed systems analysis framework.
“Polysoaps” Via Raft Copolymerization To Form Well-Defined Micelles For Water Remediation And Targeted Drug Delivery Applications,
2019
University of Southern Mississippi
“Polysoaps” Via Raft Copolymerization To Form Well-Defined Micelles For Water Remediation And Targeted Drug Delivery Applications, Phillip Pickett
Dissertations
Amphiphilic copolymers have become increasingly important for environmental and biological applications due to their behavioral characteristics in aqueous solution. For example, structurally-tailored statistical amphiphilic copolymers or “polysoaps” can self-assemble into micelles or other architectures in water at various concentrations. Polysoaps may be differentiated from small molecule surfactant micelles in their capability to self-assemble into unimolecular associates (unimolecular micelles) with no dependence on concentration. Such micelles offer enormous potential for dispersion of hydrophobic species in water at high dilution. Importantly, each polymer chain forms its own micelle and upon dilution, these micelles remain intact and capable of dispersing hydrocarbon material in …
Engineering Multifunctional And Morphologically Diverse Polymer Brush Surfaces,
2019
University of Southern Mississippi
Engineering Multifunctional And Morphologically Diverse Polymer Brush Surfaces, Cassandra M. Reese
Dissertations
The combination of surface-initiated polymerization (SIP) and post-polymerization (PPM) serves as a powerful approach to fabricate complex, multifunctional polymer films, which can be precisely tuned for desired surface engineering applications. Careful manipulation of PPM parameters such as reaction conditions, the tethered brush parameters, and the physical properties of the unbound post-modifier greatly influence the depth of penetration of the post-modifier and the polymer brush compositional heterogeneity. This dissertation focuses on engineering polymer brush surfaces with multifunctional chemistries and tunable morphologies by investigating the PPM parameters that dictate the distribution of post-modifiers on grafted polymer brush surfaces.
The first chapter of …
Exploring The Electrical Properties Of Twisted Bilayer Graphene,
2019
Linfield College
Exploring The Electrical Properties Of Twisted Bilayer Graphene, William Shannon
Senior Theses
Two-dimensional materials exhibit properties unlike anything else seen in conventional substances. Electrons in these materials are confined to move only in the plane. In order to explore the effects of these materials, we have built apparatus and refined procedures with which to create two-dimensional structures. Two-dimensional devices have been made using exfoliated graphene and placed on gold contacts. Their topography has been observed using Atomic Force Microscopy (AFM) confirming samples with monolayer, bilayer, and twisted bilayer structure. Relative work functions of each have been measured using Kelvin Probe Force Microscopy (KPFM) showing that twisted bilayer graphene has a surface potential …
Manufacturing And Testing The Permanent Magnet Linear Motor,
2019
Linfield College
Manufacturing And Testing The Permanent Magnet Linear Motor, Renjie Kang
Senior Theses
Controlled mechanical motion is vital in many useful applications in technology. Among them, linear motors have advantages over traditional rotating motors. In this work, we built a permanent magnet linear motor to test and measure its energy efficiency. A maximum 29% total energy efficiency, and 67% energy transfer rate, were detected. In addition, a C-shape support structure was added to the moving part in order to increase the moving accuracy. The tests show that, with the support structure, the fluctuation in the vertical direction decreases significantly, but the friction of the system slightly increases.
Investigation Of The Surface Topology Changes Associated With Fatigue,
2019
University of Texas at Arlington
Investigation Of The Surface Topology Changes Associated With Fatigue, Randall D. Kelton
Material Science and Engineering Dissertations - Archive
Metals have long been known to change their surface topology when subjected to a plastic strain. Given that a plastic zone exists at the tip of a propagating crack, it would seem natural to quantitatively study surface topology changes associated with nucleating and propagating fatigue cracks. So far the workers in this study have only found one measurement of the surface topology changes associated with a nucleating crack. The current research seeks to study and refine, a possible correlation between crack growth and surface topology changes, with the object to develop a damage index for fatigue cracking from surface topology …
Ultra-Small Gold Nanoparticles By Galvanic Replacement Of Larger Silver Nanoparticles,
2019
University of Texas at Arlington
Ultra-Small Gold Nanoparticles By Galvanic Replacement Of Larger Silver Nanoparticles, Chang Ting Lin
Material Science and Engineering Theses - Archive
In the last two decades, Au nanoparticles have been extensively explored for their biomedical applications, which is mainly driven by their biocompatibility and special optical properties known as surface plasmon resonance (SPR) effect. A variety of Au nanoparticles with different sizes and shapes have been synthesized and tested both in vitro and in vivo. For in vivo applications, it is usually required that Au nanoparticles can be cleared through urine (renal clearance). Renal clearance is determined by several factors of Au nanoparticles, including size, shape and surface modification. In this thesis, for the purpose of using Au nanoparticles as carriers …
Element-Specific Nanoparticle Placement Toward Fabricating Multi-Element Metastructures,
2019
University of Texas at Arlington
Element-Specific Nanoparticle Placement Toward Fabricating Multi-Element Metastructures, Lei Wu
Material Science and Engineering Theses - Archive
Nanoscale entities such as semiconductor nanoparticles, magnetic nanoparticles, metal nanoparticles, and dielectric nanoparticles have attracted a lot of attention due to their novel electrical, optical, and magnetic properties that their bulk materials cannot produce. These unique properties promise applications in nano-optical devices, ultra-sensitive sensors, single electron transistors, and high-density data storages. Moreover, to these captivating properties of the individual nanoparticles, it has been found that novel and scientifically important properties can be obtained when nanoparticles are arranged in specific configurations. Examples include nanoparticle dimers, hexamers, heptamers, and nanoparticle arrays. Until now, however, most studies have focused on one-element nanoparticle systems. …
Silicone Tadpole: Research Into Soft Bodies,
2019
University of Arkansas, Fayetteville
Silicone Tadpole: Research Into Soft Bodies, Danielle Fernandez
Mechanical Engineering Undergraduate Honors Theses
In this thesis, research is conducted in the area of soft robotics by building a soft tadpole that can deform with a specific air pressure. The goal is to mimic the motion of an organic tadpole in respect to its S-shaped tail movement. The angle of deformation, derived from material mechanic theories, ranges from 45 to 80 degrees for this type of movement. The design includes a head compartment which acts as a tank to transfer nitrogen pressure and a tail section that receives the said pressure and bends as a result. The tail section was designed with two rows …
Open Source Completely 3-D Printable Centrifuge,
2019
Michigan Technological University
Open Source Completely 3-D Printable Centrifuge, Salil S. Sule, Aliaksei Petsiuk, Joshua M. Pearce
Michigan Tech Publications, Part 1
Centrifuges are commonly required devices in medical diagnostics facilities as well as scientific laboratories. Although there are commercial and open source centrifuges, the costs of the former and the required electricity to operate the latter limit accessibility in resource-constrained settings. There is a need for low-cost, human-powered, verified, and reliable lab-scale centrifuges. This study provides the designs for a low-cost 100% 3-D printed centrifuge, which can be fabricated on any low-cost RepRap-class (self-replicating rapid prototyper) fused filament fabrication (FFF)- or fused particle fabrication (FPF)-based 3-D printer. In addition, validation procedures are provided using a web camera and free and open …
Device Engineering Of Algan/Gan Hemts For Applications In Power-Electronic And Sensing,
2019
University at Albany, State University of New York
Device Engineering Of Algan/Gan Hemts For Applications In Power-Electronic And Sensing, Isra Mahaboob
Legacy Theses & Dissertations (2009 - 2024)
The research work presented in this Ph.D. thesis focuses on the engineering of AlGaN/GaN high electron mobility transistors (HEMTs) for the development of future device technology in power electronic and sensing applications.
Design Process Of A Novel Dynamic Mechanical Analysis Sample Preparation Methodology,
2019
University of Southern Mississippi
Design Process Of A Novel Dynamic Mechanical Analysis Sample Preparation Methodology, Julian M. Richardson
Honors Theses
The technique of dynamic mechanical analysis (DMA) has been a frontrunner in the field of polymer science for decades. It’s used as a tool for characterization has been integral in mankind’s understanding of the properties of polymeric materials. The procedure for obtaining data using DMA is widespread and standardized, however the procedure for preparing the samples is a list of dimensions and tolerances with no mention of how to obtain said dimensions. Every research group using DMA is left to their own devices to prepare samples. This discontinuity can create the problem of nonuniform results across the scientific community. This …
Development Of A Multi-Probe Kelvin Scanner Device For Industrially-Relevant Characterization Of Surface-Activated Carbon Fiber Reinforced Thermoplastic Composites,
2019
Washington University in St. Louis
Development Of A Multi-Probe Kelvin Scanner Device For Industrially-Relevant Characterization Of Surface-Activated Carbon Fiber Reinforced Thermoplastic Composites, Kirby Simon
McKelvey School of Engineering Graduate Student Theses & Dissertations
Carbon fiber reinforced thermoplastic (CFRTP) composites are becoming increasingly attractive materials in manufacturing due to their lightweight nature, mechanical strength, and corrosion resistance. Surface activation of these materials is usually required during processing to increase the bond strength of assemblies (aerospace and automotive industries) or improve adhesion with implants (biomedical industry). Industrially-relevant, nondestructive quality control methods for assessing the activation state of these materials do not currently exist, however. Applying principles discovered through the use of scanning probe microscopy, a multiple-probe Kelvin scanning (MPKS) device has been developed that can assess the uniformity of the activation state of plasma-treated CFRTP …
Nanoparticle Doped Optical Fibers For High Energy Lasers,
2019
Clemson University
Nanoparticle Doped Optical Fibers For High Energy Lasers, Amber L. Vargas
All Theses
Fabrication of rare earth (RE) doped optical fibers for use in fiber-based lasers and amplifiers is conventionally performed using a solution doping technique where RE salts (i.e., ErCl3) are dissolved in a solvent, introduced into the porous silica soot, dried and consolidated to form the active fiber core. This process does not allow for tailoring of the chemical environment about the RE. Alternatively, nanoparticle (NP) doping is more recent approach to incorporating rare earths into an optical fiber and have been shown to permit modification of the chemical environment around the RE in ways the enhance spectroscopic performance. This is …
Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure,
2019
University of Arkansas, Fayetteville
Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu
Graduate Theses and Dissertations
Recently, various groups have demonstrated nano-scale engineering of nanostructures for optical to infrared wavelength plasmonic applications. Most fabrication technique processes, especially those using noble metals, requires an adhesion layer. Previously proposed theoretical work to support experimental measurement often neglect the effect of the adhesion layers. The first finding of this work focuses on the impact of the adhesion layer on nanoparticle plasmonic properties. Gold nanodisks with a titanium adhesion layer are investigated by calculating the scattering, absorption, and extinction cross-section with numerical simulations using a finite difference time domain (FDTD) method. I demonstrate that a gold nanodisk with an adhesive …
Fundamental Core Effects In Co-Cr-Fe-Ni Based High Entropy Alloys,
2019
University of Central Florida
Fundamental Core Effects In Co-Cr-Fe-Ni Based High Entropy Alloys, Abhishek Mehta
Electronic Theses and Dissertations
High entropy alloys (HEAs) are near equiatomic multi-principal-element-alloys (MPEAs) which are different from traditional solvent-based multicomponent alloys. Based on initial work by Yeh and Co-workers, they were proposed to exhibit four "core" effects: high entropy, sluggish diffusion, lattice distortion, and cocktail effect. Present work investigates two of the four "core" effects, i.e. high entropy and sluggish diffusion effects, in Co-Cr-Fe-Ni based transition metal high entropy alloys. Solid-to-solid diffusion couple approach was adopted to investigate, these core effects. Experimental results contradicts the "high entropy" effect based on thermodynamics analysis: that the HEAs with low entropy of mixing may be thermodynamically more …
Understanding The Effect Of Crystalline Structure And Atomic Arrangement In Metal Oxide Electrodes For Sodium Ion Batteries,
2019
Boise State University
Understanding The Effect Of Crystalline Structure And Atomic Arrangement In Metal Oxide Electrodes For Sodium Ion Batteries, Changjian Deng
Boise State University Theses and Dissertations
This dissertation investigates the fundamental understanding in the influences of order-disorder and atomic arrangement on electrochemical properties of electrode materials for sodium ion batteries (SIBs). In specific, TiO2 anode and NaNixFeyMnxO2 cathode materials are studied. Due to their low cost and relatively high abundance of raw materials SIBs are attractive for large-scale energy storage systems for high round trip efficiency and long cycle life. Recent studies suggest that various polymorphs of TiO2 are suitable as anode material. However, the impact of crystallinity on the electrochemical properties of the material has not …
Methods To Remotely Eliminate Biofilm From Medical Implants Using 2.4 Ghz Microwaves,
2019
University of Arkansas, Fayetteville
Methods To Remotely Eliminate Biofilm From Medical Implants Using 2.4 Ghz Microwaves, Brett Glenn
Mechanical Engineering Undergraduate Honors Theses
Infections associated with biofilm growth are usually challenging to eradicate due to their high tolerance toward antibiotics [11, 12]. Biofilms often form on the inert surfaces of medically implanted devices [13]. No matter the sophistication, microbial infections can develop on all medical devices and tissue engineering constructs [12]. Related infections lead to 2 million cases annually in the U.S., costing the healthcare system over $5 billion in additional healthcare expenses [12].
Novel solutions to biofilm’s microbial colonization span the spectrum of engineering and science disciplines. Yet a practical solution still does not exist. The research presented here will explore a …
