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Novel Engineered Nanostructured Complex Oxide For High Temperature Thermoelectric Power Generation, Diego F. Palacio
Novel Engineered Nanostructured Complex Oxide For High Temperature Thermoelectric Power Generation, Diego F. Palacio
Graduate Theses, Dissertations, and Problem Reports
Thermoelectric power generators are a promising technology that can produce electrical power directly from waste heat emitted in energy production and consumption systems. The essential component of thermoelectric generators is the thermoelectric material which performs the energy conversion process. In order to make thermoelectric devices to be considered a significant contributor to US energy infrastructure, it is essential first to foster improvements in high performance thermoelectric materials. They must possess not only a high conversion efficiency, but also need be composed of nontoxic and abundantly available elemental materials having high chemical stability in air up to 800-1000 K. In comparison …
Tribological Analysis Of Hydrophobic Thin Film With Antimicrobial Properties, Elizabeth E. Defusco
Tribological Analysis Of Hydrophobic Thin Film With Antimicrobial Properties, Elizabeth E. Defusco
Graduate Theses, Dissertations, and Problem Reports
Silica based sol gel thin films have become a very popular area of research due to their high degree of variability and ease of manufacturing. They are commonly used as coatings for many applications in the consumer electronics and automotive industries. Some common properties in these thin films include optical transparency, wear resistance, antimicrobial, hydrophobic, electromagnetic, etc.;The coating produced in this research has been tailored to meet three key functions; durability, hydrophobicity, and anti-microbial properties. This coating is created through a three-step sol gel reaction mechanism. The starting chemical, tetraethoxysilane (TEOS), yields the final product of a silicon dioxide matrix. …
Pre And Post Blast Chemical Comparison Of The Intra- And Inter-Variability Of Metal Pipes Commonly Used In Pipe Bombs, Mandi Hellested
Pre And Post Blast Chemical Comparison Of The Intra- And Inter-Variability Of Metal Pipes Commonly Used In Pipe Bombs, Mandi Hellested
Graduate Theses, Dissertations, and Problem Reports
Pipe bombs are a substantial problem around the world killing and injuring thousands each year. Traditionally explosive used, residues of explosives, and bomb components have been the main source of evidence in the investigation of a located or exploded pipe bomb. This research analyzed the trace elemental compositions of metal pipes to investigate if pipes can be compared. It was found that in a sample set of 37 pipes, of different brands and purchase locations, each pipe was homogenous at trace elemental concentrations. This homogeneity allowed for comparison between pipes. An x-ray tube, as an alternate excitation source, which had …
A Phase Separation Study Of Biological Polymers In Solid State Films, Jaclyn Nicole Kokx
A Phase Separation Study Of Biological Polymers In Solid State Films, Jaclyn Nicole Kokx
Graduate Theses, Dissertations, and Problem Reports
A growing need for nanoparticle-polymeric composite materials in the electronics and coatings industries has driven research to gain a better understanding of the mechanisms of self-assembled phase separation in polymer thin films and experiment with controlling the phase separation behavior of multicomponent polymer systems. This research proposed that biological polymers have the ability to phase separate into defined structures capable of organizing nanoparticles with unparallel control over the architecture of the molecule compared to synthetic polymers.;This study used recombinant DNA techniques and the expression host E. coli to accurately and repeatedly produce a peptide with a random coil secondary structure. …
Structural And Mechanical Properties Of Silica And Hybrid Aerogels And Xerogels Studied Using Molecular Dynamics Simulations, John Sandro Rivas Murillo
Structural And Mechanical Properties Of Silica And Hybrid Aerogels And Xerogels Studied Using Molecular Dynamics Simulations, John Sandro Rivas Murillo
Graduate Theses, Dissertations, and Problem Reports
The structural and mechanical properties of silica and hybrid aerogels and xerogels are studied using Molecular Dynamics simulations. Hybrid samples are created by adding methyl groups (CH3) to the silica structure. Silica samples are generated expanding a dense silica glass in a simulation box of volume chosen to produce a porous sample of a specified density. The expanded glass is thermally treated using a combination of heating and cooling processes. The heating process increases the kinetic energy of the atoms in the system, which facilitates their movement throughout the system. The cooling process reduces the kinetic energy of the atoms …
Nanostructure And Chemistry Evolution Of Solid Oxide Fuel Cells Upon Cell Operation, Song Chen
Nanostructure And Chemistry Evolution Of Solid Oxide Fuel Cells Upon Cell Operation, Song Chen
Graduate Theses, Dissertations, and Problem Reports
Solid Oxide Fuel Cells (SOFCs) are clean and efficient alternatives to conventional power generation technology. In SOFC, electrochemical reactions take place on the triple-phase boundaries (TPBs) between the electrolyte, the electrode and the gaseous fuel. Small changes in TPB structure or chemistry, and the interface between electrode and electrolyte can drastically affect SOFC performance and lifetime. However, very limited experimental work has been reported on the nanostructure and chemistry evolution of interface and TPBs in the SOFC upon cell operation.;The main goal of this dissertation is to investigate the nanostructure and chemistry of the grain boundaries and interfaces including TPB …
Chirality Sorted Single Walled Carbon Nanotubes For Random Network Thin Film Applications, Volkan Ozyar
Chirality Sorted Single Walled Carbon Nanotubes For Random Network Thin Film Applications, Volkan Ozyar
Graduate Theses, Dissertations, and Problem Reports
Single-walled carbon nanotubes (SWNTs) are comprised entirely of carbon atoms which lie in a graphitic plane rolled into a seamless cylinder. The direction in which the graphic plane is rolled affects the subsequent chiralities of the SWNTs. This direction is called the chiral vector. This chiral vector, Ch =na1+ma2, is described in terms of a pair of integers (n,m) and a pair of lattice vectors (a1,a2) associated with each carbon atom in the graphene sheet. The magnitude of the chiral vector determines the diameter of the nanotubes as d= Ch/pi. SWNTs with integers n-m =3i, where i = 0, 1, …
Sol-Gel Derived Wear-Resistant, Hydrophobic, Particle-Reinforced Silica Coatings, Derrick A. Banerjee
Sol-Gel Derived Wear-Resistant, Hydrophobic, Particle-Reinforced Silica Coatings, Derrick A. Banerjee
Graduate Theses, Dissertations, and Problem Reports
Hydrophobic coatings are useful for a wide range of applications including anti-fouling, anti-corrosive, and anti-icing. There are also a number of emerging applications in which transparency is critical such as optoelectronics, touchscreens, and smart windows. For many of these applications, resistance to abrasive wear is also important. Typical low-surface energy coatings such as polytetrafluoroethylene (PTFE) have poor mechanical strength which leaves them susceptible to abrasive wear. To combat this problem, functional moieties can be encapsulated using a sol-gel method to provide improved substrate adhesion and hardness while maintaining transparency and functionality. While this provides an improvement for many applications, the …
Investigation Of Structural Properties Of Organic Thin Films For Solar Cell And Transistor Applications, Ronak Rahimi
Investigation Of Structural Properties Of Organic Thin Films For Solar Cell And Transistor Applications, Ronak Rahimi
Graduate Theses, Dissertations, and Problem Reports
For the past several decades, organic materials including polymers, oligomers and small molecules have been of great interest for their various applications in the electronics and the semiconductor industry. The most appealing advantages of organic materials compared to their inorganic counterparts are their compatibility with flexible substrates and amenability to low-temperature and low-cost fabrication processes such as evaporation, spin-coating and printing. Moreover, the ability to be utilized in fabrication of lightweight and large-area devices is among other reasons for popularity of organic materials. A large number of studies have reported on various aspects of the development and optimization of organic …
Electronic Structure Of Delafossites For Improved Photocatalysis, M. Kylee Underwood
Electronic Structure Of Delafossites For Improved Photocatalysis, M. Kylee Underwood
Graduate Theses, Dissertations, and Problem Reports
One of the most pressing issues for scientists today is the ever increasing amount of greenhouse gases entering the atmosphere. Carbon dioxide is considered the most prominent greenhouse gas, and emissions from fossil fuel power generation alone represent 26% of global CO2 emissions. Here we computationally examine the properties of a family of materials called delafossites for the photoreduction of CO2 emissions produced through fossil fuel power generation. These materials show promise to reduce CO2 into usable products such as methane through photoelectrochemical reduction. Delafossites are of interest due to the discrepancy between their fundamental and optically measured band gaps. …
Degradation Of Solid Oxide Fuel Cell Anode In Phosphorus-Containing Coal Syngas, Jinlong Yan
Degradation Of Solid Oxide Fuel Cell Anode In Phosphorus-Containing Coal Syngas, Jinlong Yan
Graduate Theses, Dissertations, and Problem Reports
Coal is the dominant energy for electric power generation. Solid oxide fuel cells (SOFCs) has been proposed to be incorporated into the coal based power plant. Currently, Nickel-Yttria stabilized Zirconia (YSZ) composite is widely used as the anode in SOFCs (YSZ as electrolyte) due to its low-cost, high electric conductivity, and excellent catalytic activity for many fuel types. However, the long-term stability of the Ni/YSZ anode remains a major concern when a SOFC is operated using coal syngas. Poisoning by the impurity species in the coal syngas poses severe threat on the SOFCs. Of all the impurities present in coal …
Synthesis Of Functional 1,2,3-Triazoles And Its Applications In Transition Metal Catalysis, Wuming Yan
Synthesis Of Functional 1,2,3-Triazoles And Its Applications In Transition Metal Catalysis, Wuming Yan
Graduate Theses, Dissertations, and Problem Reports
Several new methodologies for synthesizing functional 1,2,3-triazoles which include arylation, vinylation, propargylation and allenation, have been successfully developed. These resulting new methods are of great benefit to the organic chemists who are working on the research fields related to 1,2,3-triazoles. Particularly, the iron catalyzed propargylation and allenation have initiated the iron chemistry with 1,2,3-triazoles as the ligand. For example, our efforts led to the discovery of a practical approach for the synthesis of conjugated enynes that is challenging through conventional methods. In the synthesis of conjugated enyne, 1,2,3-triazoles were revealed as the only ligand effectively promoting this important and challenging …