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Laser Induced Breakdown Spectroscopy For Detection Of Organic Residues Impact Of Ambient Atmosphere And Laser Parameters, Christopher G. Brown Jan 2011

Laser Induced Breakdown Spectroscopy For Detection Of Organic Residues Impact Of Ambient Atmosphere And Laser Parameters, Christopher G. Brown

Electronic Theses and Dissertations

Laser Induced Breakdown Spectroscopy (LIBS) is showing great potential as an atomic analytical technique. With its ability to rapidly analyze all forms of matter, with little-to-no sample preparation, LIBS has many advantages over conventional atomic emission spectroscopy techniques. With the maturation of the technologies that make LIBS possible, there has been a growing movement to implement LIBS in portable analyzers for field applications. In particular, LIBS has long been considered the front-runner in the drive for stand-off detection of trace deposits of explosives. Thus there is a need for a better understanding of the relevant processes that are responsible for …


Comparing Media Coverage Of The Gulf Oil Spill In The Us And Uk Implications For Global Crisis Communication, Sarah Crytzer Jan 2011

Comparing Media Coverage Of The Gulf Oil Spill In The Us And Uk Implications For Global Crisis Communication, Sarah Crytzer

Electronic Theses and Dissertations

The following research is a content analysis of 114 articles written by the American and British news media outlets in the first month following the BP Gulf oil spill in April 2010. The goal of the research was to identify any dominant frames evident in the reports and to compare the two countries to see if there was a difference in the dominant frames used. Positive, negative, and neutral tones were also evaluated to determine if there was a difference between the countries. The results show that both countries reports predominantly used an ecology and action frame, while British media …


Comparative Study Of Ethanol And Methanol Electro-Oxidation On A Platinum/Ceria Composite Electrode In Alkaline And Acid Solutions : Electro-Catalytic Performance And Reaction Kinetics, Carlos Humberto Hidalgo Martinez Jan 2011

Comparative Study Of Ethanol And Methanol Electro-Oxidation On A Platinum/Ceria Composite Electrode In Alkaline And Acid Solutions : Electro-Catalytic Performance And Reaction Kinetics, Carlos Humberto Hidalgo Martinez

Electronic Theses and Dissertations

A comparative study of the electro-oxidation of ethanol and methanol was carried out on a Pt/ceria composite electrode prepared by electro-deposition. Modification of the Pt electrode was realized by co-deposition from a 1.0 mM K₂PtCl₆ solution that also contained a 20 mM suspension of ceria. The electro-catalytic activities and stabilities of the Pt/ceria catalyst towards ethanol electro-oxidation reactions (EOR) and methanol electro-oxidation reactions (MOR) were investigated by potentiodynamic and potentiostatic methods in 0.5 M sulfuric acid and 1.0 M sodium hydroxide solutions at various concentrations of ethanol and methanol. The kinetics of ethanol and methanol on a Pt/ceria composite electrode …


Tunneling Conductance Characterization Of A Quantum Dot In The Fractional Quantum Hall Regime, Douglas E. Willard Jan 2011

Tunneling Conductance Characterization Of A Quantum Dot In The Fractional Quantum Hall Regime, Douglas E. Willard

Electronic Theses and Dissertations

This work represents a first-principles calculation of the electron tunneling current into quantum dots in the fractional quantum Hall effect regime. The system under consideration consists of an idealized Scanning Tunneling Microscope (STM) tip and a quantum dot with disk geometry and interacting electrons in a transverse magnetic field. Within the context of this model the tunneling current between the STM tip and the dot is examined for spin-polarized electrons at and around a filling factor of 1/3. The current expression is based on a second-quantized Hamiltonian in which electrons in the dot are interacting, confined, and restricted to the …


Investigations On Morphology, Spectroscopy And Near-Infrared Photoresponse Sensitization Of Conjugated Polymers In Organic Photovoltaics, Zhongjian Hu Jan 2011

Investigations On Morphology, Spectroscopy And Near-Infrared Photoresponse Sensitization Of Conjugated Polymers In Organic Photovoltaics, Zhongjian Hu

Electronic Theses and Dissertations

Conjugated polymer architecture and morphology are two of the key factors that determine corresponding opto-electronic device performance. It is well-known that conjugated polymers display a variety of conformations and exhibit aggregation in their materials and even for individual polymer chains. The intrinsic structural heterogeneity of conjugated polymers strongly complicates the active layer morphology and phase separation, which are crucial for photoinduced charge generation and transport in polymer based bulk heterojunction-organic photovoltaics device (BHJ-OPVs). Aiming to probe the molecular level correlations between conjugated polymer architecture, morphology and optoelectronic properties, single molecule spectroscopy (SMS) and single particle spectroscopy (SPS) were employed. The …


Effective Task Transfer Through Indirect Encoding, Phillip Verbancsics Jan 2011

Effective Task Transfer Through Indirect Encoding, Phillip Verbancsics

Electronic Theses and Dissertations

An important goal for machine learning is to transfer knowledge between tasks. For example, learning to play RoboCup Keepaway should contribute to learning the full game of RoboCup soccer. Often approaches to task transfer focus on transforming the original representation to fit the new task. Such representational transformations are necessary because the target task often requires new state information that was not included in the original representation. In RoboCup Keepaway, changing from the 3 vs. 2 variant of the task to 4 vs. 3 adds state information for each of the new players. In contrast, this dissertation explores the idea …


The Application Of Chemometrics To The Detection And Classification Of Ignitable Liquids In Fire Debris Using The Total Ion Spectrum, Jennifer N. Lewis Jan 2011

The Application Of Chemometrics To The Detection And Classification Of Ignitable Liquids In Fire Debris Using The Total Ion Spectrum, Jennifer N. Lewis

Electronic Theses and Dissertations

Current methods in ignitable liquid identification and classification from fire debris rely on pattern recognition of ignitable liquids in total ion chromatograms, extracted ion profiles, and target compound comparisons, as described in American Standards for Testing and Materials E1618-10. The total ion spectra method takes advantage of the reproducibility among sample spectra from the same American Society for Testing and Materials class. It is a method that is independent of the chromatographic conditions that affect retention times of target compounds, thus aiding in the use of computer-based library searching techniques. The total ion spectrum was obtained by summing the ion …


Self-Assembly Of Amyloid Aggregates Simulated With Molecular Dynamics, Workalemahu Mikre Berhanu Jan 2011

Self-Assembly Of Amyloid Aggregates Simulated With Molecular Dynamics, Workalemahu Mikre Berhanu

Electronic Theses and Dissertations

Amyloids are highly ordered cross-β sheet aggregates that are associated with many diseases such as Alzheimer‟s, type II diabetes and prion diseases. Recently a progress has been made in structure elucidation, environmental effects and thermodynamic properties of amyloid aggregates. However, detailed understanding of how mutation, packing polymorphism and small organic molecules influence amyloid structure and dynamics is still lacking. Atomistic modeling of these phenomena with molecular dynamics (MD) simulations holds a great promise to bridge this gap. This Thesis describes the results of MD simulations, which provide insight into the effects of mutation, packing polymorphism and molecular inhibitors on amyloid …