Self-Contained Breathing Apparatus For Firefighter With A Permanent Stoma,
2015
California Polytechnic State University, San Luis Obispo
Self-Contained Breathing Apparatus For Firefighter With A Permanent Stoma, Jason Delgadillo, Aaron Wheeler, Zachary Wishbow
Biomedical Engineering
The purpose of this project was to create a unique SCBA (self-contained breathing apparatus) for a firefighter named Chris Gauer. This prototype consists of a SCBA headgear connected to a polycarbonate-formed stoma mask with a medical-grade sanitary silicone hose.
Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration,
2015
California Polytechnic State University - San Luis Obispo
Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration, Caitlyn Cook
Materials Engineering
The top contact electrode layers of nine organic photovoltaic cells were prepared with two varying factors: three Silver nanowire (AgNW) densities deposited on a conductive polymer doped with three concentrations. Silver’s low sheet resistance of 20-Ω/sq is hypothesized to lower the sheet resistance of the anode layer and thus enhance the overall efficiency of the cell. Four-point probe measurements indicated that increasing AgNW density in the top contact electrode layer of an organic photovoltaic cell significantly reduces sheet resistance from 52.2k-Ω/sq to 18.0 Ω/sq. Although an increase in doping concentration of the conductive polymer reduced sheet resistance in low AgNW …
Optimization Of Graphene-Based Materials Outperforming Host Epoxy Matrices,
2015
University of Salerno
Optimization Of Graphene-Based Materials Outperforming Host Epoxy Matrices, Liberata Guadagno, Marialuigia Raimondo, Luigi Vertuccio, Marco Mauro, Gaetano Guerra, Khalid Lafdi, Biagio De Vivo, Patrizia Lamberti, Giovanni Spinelli, Vincenzo Tucci
Chemical and Materials Engineering Faculty Publications
The degree of graphite exfoliation and edge-carboxylated layers can be controlled and balanced to design lightweight materials characterized by both low electrical percolation thresholds (EPT) and improved mechanical properties. So far, this challenging task has been undoubtedly very hard to achieve.
The results presented in this paper highlight the effect of exfoliation degree and the role of edge-carboxylated graphite layers to give self-assembled structures embedded in the polymeric matrix. Graphene layers inside the matrix may serve as building blocks of complex systems that could outperform the host matrix. Improvements in electrical percolation and mechanical performance have been obtained by a …
Computational Multiscale Modeling And Characterization Of Piezoresistivity In Fuzzy Fiber Reinforced Polymer Composites,
2015
Virginia Tech
Computational Multiscale Modeling And Characterization Of Piezoresistivity In Fuzzy Fiber Reinforced Polymer Composites, Xiang Ren, Josh Burton, Gary D. Seidel, Khalid Lafdi
Chemical and Materials Engineering Faculty Publications
In this paper, the piezoresistive response (i.e. the change of resistance under the application of strain) of polymer composites reinforced by a novel material known as fuzzy fibers is characterized by using single tow piezoresistive fragmentation tests and modeled by using a 3D computational multiscale model based on the finite element analysis. In the characterization work, the fuzzy fiber tow is embedded in a dog-bone specimen infused by epoxy, with resistance and displacement measured simultaneously to obtain its piezoresistive response. An approximately linear and stable piezoresistive response is observed within the fuzzy fiber tow region yielding gauge factors on average …
Enhanced Presentation Of Tomographic Data,
2015
CSUMB
Enhanced Presentation Of Tomographic Data, Carmen Watts Clayton, Bernice E. Mills, George Buffleben, Thien Vu-Nguyen
STAR Program Research Presentations
Solid materials can now be viewed non-destructively with x-rays by tomography; a technique for taking many 2D images of an object at many angles and reconstructing the images into a 3D data cube. The data is next rendered into 2D or 3D still images or movies. By nature, x-ray tomography yields a very large amount of data in three dimensions. Effectively displaying this data to an audience is a challenge.
In this work techniques are explored to improve the presentation methods of movies of both 2D and 3D tomographic data for visual appeal and correct perspective. Finding the optimal ways …
Nanohub.Org: A Gateway To Undergraduate Simulation-Based Research In Materials Science And Related Fields,
2015
Purdue University
Nanohub.Org: A Gateway To Undergraduate Simulation-Based Research In Materials Science And Related Fields, Tanya A. Faltens, Peter A. Bermel, Amanda Buckles, K Anna Douglas, Alejandro H. Strachan, Lynn K. Zentner, Gerhard Klimeck
Birck and NCN Publications
Our future engineers and scientists will likely be required to use advanced simulations to solve many of tomorrow's challenges in nanotechnology. To prepare students to meet this need, the Network for Computational Nanotechnology (NCN) provides simulation-focused research experiences for undergraduates at an early point in their educational path, to increase the likelihood that they will ultimately complete a doctoral program. The NCN summer research program currently serves over 20 undergraduate students per year who are recruited nationwide, and selected by NCN and the faculty for aptitude in their chosen field within STEM, as well as complementary skills such as coding …
Temporally And Spatially Resolved Plasma Spectroscopy In Pulsed Laser Deposition Of Ultra-Thin Boron Nitride Films,
2015
Air Force Research Laboratory
Temporally And Spatially Resolved Plasma Spectroscopy In Pulsed Laser Deposition Of Ultra-Thin Boron Nitride Films, Nicholas R. Glavin, Christopher Muratore, Michael L. Jespersen, Jianjun Hu, Timothy S. Fisher, Andrey A. Voevodin
Chemical and Materials Engineering Faculty Publications
Physical vapor deposition (PVD) has recently been investigated as a viable, alternative growth technique for two-dimensional materials with multiple benefits over other vapor deposition synthesis methods. The high kinetic energies and chemical reactivities of the condensing species formed from PVD processes can facilitate growth over large areas and at reduced substrate temperatures. In this study, chemistry, kinetic energies, time of flight data, and spatial distributions within a PVD plasma plume ablated from aboron nitride (BN) target by a KrF laser at different pressures of nitrogen gas were investigated. Time resolved spectroscopy and wavelength specific imaging were used to identify and …
Influence Of Calcium Sulfoaluminate Cement On The Pullout Performance Of Reinforcing Fibers: An Evaluation Of The Micro-Mechanical Behavior,
2015
University of Kentucky
Influence Of Calcium Sulfoaluminate Cement On The Pullout Performance Of Reinforcing Fibers: An Evaluation Of The Micro-Mechanical Behavior, Robert B. Jewell
Theses and Dissertations--Civil Engineering
The objective of this research was to determine the influence of calcium sulfoaluminate (CSA) cement on reinforcing fibers by evaluating the fiber pullout behavior, and bonding characteristics, of a single fiber embedded in a cementitious paste matrix. Four types of fibers commonly used in industry were evaluated: 1) Polyvinyl alcohol; 2) Polypropylene; 3) Coated Steel; and 4) Plain Steel.
Upward trends in energy costs and potential greenhouse gas regulations favor an increased use of construction materials that require lower energy and lower CO2 emissions to fabricate, such as CSA cement, as opposed to the production of ordinary portland cement …
Effects Of Magnetic Field On The Shape Memory Behavior Of Single And Polycrystalline Magnetic Shape Memory Alloys,
2015
University of Kentucky
Effects Of Magnetic Field On The Shape Memory Behavior Of Single And Polycrystalline Magnetic Shape Memory Alloys, Ali S. Turabi
Theses and Dissertations--Mechanical and Aerospace Engineering
Magnetic Shape Memory Alloys (MSMAs) have the unique ability to change their shape within a magnetic field, or in the presence of stress and a change in temperature. MSMAs have been widely investigated in the past decade due to their ability to demonstrate large magnetic field induced strain and higher frequency response than conventional shape memory alloys (SMAs). NiMn-based alloys are the workhorse of metamagnetic shape memory alloys since they are able to exhibit magnetic field induced phase transformation. In these alloys, martensite and austenite phases have different magnetization behavior, such as the parent phase can be ferromagnetic and martensite …
Shape Memory Behavior Of Single Crystal And Polycrystalline Ni-Rich Nitihf High Temperature Shape Memory Alloys,
2015
University of Kentucky
Shape Memory Behavior Of Single Crystal And Polycrystalline Ni-Rich Nitihf High Temperature Shape Memory Alloys, Sayed M. Saghaian
Theses and Dissertations--Mechanical and Aerospace Engineering
NiTiHf shape memory alloys have been receiving considerable attention for high temperature and high strength applications since they could have transformation temperatures above 100 °C, shape memory effect under high stress (above 500 MPa) and superelasticity at high temperatures. Moreover, their shape memory properties can be tailored by microstructural engineering. However, NiTiHf alloys have some drawbacks such as low ductility and high work hardening in stress induced martensite transformation region. In order to overcome these limitations, studies have been focused on microstructural engineering by aging, alloying and processing.
Shape memory properties and microstructure of four Ni-rich NiTiHf alloys (Ni50.3Ti29.7Hf20, Ni50.7Ti29.3Hf20, …
Effects Of Disorder State And Interfacial Layer On Thermal Transport In Copper/Diamond System,
2015
Air Force Research Laboratory
Effects Of Disorder State And Interfacial Layer On Thermal Transport In Copper/Diamond System, Vikas Sinha, Jaime J. Gengler, Christopher Muratore, Jonathan E. Spowart
Chemical and Materials Engineering Faculty Publications
The characterization of Cu/diamond interface thermal conductance (hc) along with an improved understanding of factors affecting it are becoming increasingly important, as Cu-diamond composites are being considered for electronic packaging applications. In this study, ∼90 nm thick Cu layers weredeposited on synthetic and natural single crystal diamond substrates. In several specimens, a Ti-interface layer of thickness ≤3.5 nm was sputtered between the diamond substrate and the Cu top layer. The hc across Cu/diamond interfaces for specimens with and without a Ti-interface layer was determined usingtime-domain thermoreflectance. The hc is ∼2× higher for similar interfacial layers on …
Nanomechanical And Scaling Behavior Of Nanoporous Gold,
2015
University of Kentucky
Nanomechanical And Scaling Behavior Of Nanoporous Gold, Nicolas J. Briot
Theses and Dissertations--Chemical and Materials Engineering
Nanoporous metals have recently been drawn significant interest in various fields of research. Their high surface-to-volume ratio present a strong potential for applications in sensing, catalysis, micro-electromechanical systems (MEMS) and even in the medical field. However, the mechanical properties of nanoporous metals have not yet been well determined, as conducting mechanical tests was found to be challenging. Scaling relations linking the mechanical properties of porous materials to those of their dense counterparts are successfully and widely used for many porous metals. However, their applicability to nanoporous metals have recently been questioned, as estimations from the classic scaling relations were found …
Nanoindentation Of A Zinc Metal Soap Mixture For Use In A Laser Printer,
2015
University of Kentucky
Nanoindentation Of A Zinc Metal Soap Mixture For Use In A Laser Printer, George A. Nimick
Theses and Dissertations--Chemical and Materials Engineering
At the start of this project, the possible choices of metal soaps had already been narrowed to include some of the zinc soaps used in this project. These zinc soaps are mixtures of zinc stearate and zinc palmitate of varying ratios purchased from a supplier. Zinc soap was chosen as result of its common use in various industries as a lubricant and mold release, which implied potential benefits in an electrophotographic printing system. These potential benefits include, but are not limited to, a more efficient transfer from a photoconductive drum and protection of the drum from mechanical and chemical degradation. …
Microindentation Of Bi57in26sn17 Lead-Free Alloy,
2015
University of Kentucky
Microindentation Of Bi57in26sn17 Lead-Free Alloy, Ruiting Zhao
Theses and Dissertations--Chemical and Materials Engineering
There is great need to understand the mechanical properties of lead-free alloys—an alternative of lead-based alloys—to address the environmental problems associated with the use of lead-based materials in microelectronics. In this work, the microstructures of Bi57In26Sn17 lead-free alloy were examined using Optical Microscopy and Energy Dispersive X-ray Spectroscopy analysis. The micro-indentation technique was used to study the mechanical properties of Bi57In26Sn17 lead-free alloy. The experimental results of the hardness and contact modulus were presented and discussed. Local creep during the indentation was observed from the load-displacement curves. The Vickers hardness (HV) increases with the decrease of the indentation depth, suggesting …
Synthesis, Structure, Properties And Applications Of Nanoporous Silicon And Palladium,
2015
University of Kentucky
Synthesis, Structure, Properties And Applications Of Nanoporous Silicon And Palladium, Xu Jiang
Theses and Dissertations--Chemical and Materials Engineering
Nanoporous (np) materials with pore size below 100 nano-meters exist naturally in biological and mineral structures, and synthetic np materials have been used industrially for centuries. Np materials have attracted significant research interest in recent decades, as the development of new characterization techniques and nanotechnology allow the observation and design of np materials at a new level. This study focuses on two np materials: nanoporous silicon (np-Si) and nanoporous palladium (np-Pd).
Silicon (Si), because of its high capacity to store lithium (Li), is increasingly becoming an attractive candidate as anode material for Li ion batteries (LIB). One significant problem with …
The Examination Of Stress Corrosion Cracking In High Strength Carbon Steel Through Combined Mechanical-Electrochemical Testing,
2015
University of Akron Main Campus
The Examination Of Stress Corrosion Cracking In High Strength Carbon Steel Through Combined Mechanical-Electrochemical Testing, Jacob Sines
Williams Honors College, Honors Research Projects
Through the analysis of materials and environments seen in industry a better understanding of the fundamentals behind degradation mechanisms can be observed. The scope of this project was to better understand the fundamentals behind the degradation of high strength pipeline steels in a lab setting to simulate an environment seen in industry. Specifically the degradation mechanisms of high and nearly neutral pH stress corrosion cracking were examined in environments that simulated oil and gas pipelines buried in soil. Experimentation was carried out utilizing X65 carbon steel specimen, a Gamry potentiostat, a CORTEST proof ring, a CORTEST slow strain rate machine, …
A Study To Evaluate Non-Uniform Phase Maps In Shape Memory Alloys Using Finite Element Method,
2015
Virginia Commonwealth University
A Study To Evaluate Non-Uniform Phase Maps In Shape Memory Alloys Using Finite Element Method, Naren Motte
Theses and Dissertations
The unique thermo-mechanical behavior of Shape Memory Alloys (SMAs), such as their ability to recover the original shape upon heating or being able to tolerate large deformations without undergoing plastic transformations, makes them a good choice for actuators.
This work studies their application in the aerospace and defense industries where SMA components can serve as release mechanisms for gates of enclosures that have to be deployed remotely. This work provides a novel approach in evaluating the stress and heat induced change of phase in a SMA, in terms of the transformation strain tensor. In particular, the FEA tool
ANSYS has …
The Future Of Carbon-Based Scaffolds In Foot And Ankle Surgery,
2015
University of Dayton
The Future Of Carbon-Based Scaffolds In Foot And Ankle Surgery, Jarema S. Czarnecki, Khalid Lafdi, Panagiotis A. Tsonis
Chemical and Materials Engineering Faculty Publications
Autologous grafts have been the gold standard in tissue replacement and the most accurate means of recapitulating both the biological and mechanical properties of tissue. However, autologous grafts have had complications and drawbacks. Skin grafting, a prime example of an autologous tissue graft, has been limited by the size of graft, availability, and secondary donor site morbidity. Use of cadaveric tissues circumvents several limitations of autologous grafts; however, sterilization processes used to reduce the risk of disease transmission potentially weaken tissues and eliminate living cells and some growth factors from scaffolds, making them suboptimal tissue replacements. Chemical cross-linkage of tissue …
Investigation Of Fatigue Life And Fracture Mechanics Of Unconstrained Ni-Mn-Ga Single Crystals,
2014
Boise State University
Investigation Of Fatigue Life And Fracture Mechanics Of Unconstrained Ni-Mn-Ga Single Crystals, Theodore Bryson Lawrence
Boise State University Theses and Dissertations
Ni-Mn-Ga is a magnetic shape memory alloy (MSMA) that exhibits large recoverable strains. The magnetic field induced strain (MFIS) occurs through twin boundary motion resulting in reorientation of the crystal structure, which is coupled to the magnetic moment of the material. The shape memory capabilities of the material make it promising for applications including microactuators, sensors, microfluid pumps, refrigeration, energy harvesting, and data storage.
In order for Ni-Mn-Ga to become a viable option for use in commercial applications the performance and reliability must be on par with industry standards. Ni‑Mn-Ga has been shown to achieve high cycles at low strains, …
Early-Age Hydration Studies Of Portland Cement,
2014
University of Louisville
Early-Age Hydration Studies Of Portland Cement, Fengjuan Liu
Electronic Theses and Dissertations
Our current knowledge on cement hydration during setting is based on the discrete observation of hydrated paste. An advanced micro/nano-level technique which can perform the in-situ observation on the continuous hydration of cement paste is demanded. In this study, Raman spectroscopy (RS) was chosen as such a method to continuously investigate wet pastes. The objective of this research is to explore the hydration process and microstructural development of fresh pastes with this technique. This research was conducted in three phases. First, the RS analysis was used to continuously observe the cement hydration from 20 minutes after mixing to 9 hours. …
