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Theoretical Analysis Of Single Molecule Spectroscopy Lineshapes Of Conjugated Polymers, Murali Devi 2016 Graduate Center, City University of New York

Theoretical Analysis Of Single Molecule Spectroscopy Lineshapes Of Conjugated Polymers, Murali Devi

All Dissertations, Theses, and Capstone Projects (2014-Present)

Conjugated Polymers(CPs) exhibit a wide range of highly tunable optical properties. Quantitative and detailed understanding of the nature of excitons responsible for such a rich optical behavior has significant implications for better utilization of CPs for more efficient plastic solar cells and other novel optoelectronic devices. In general, samples of CPs are plagued with substantial inhomogeneous broadening due to various sources of disorder. Single molecule emission spectroscopy (SMES) offers a unique opportunity to investigate the energetics and dynamics of excitons and their interactions with phonon modes. The major subject of the present thesis is to analyze and understand room ...


Classical Transport In Disordered Systems, Antonios Papaioannou 2016 Graduate Center, City University of New York

Classical Transport In Disordered Systems, Antonios Papaioannou

All Dissertations, Theses, and Capstone Projects (2014-Present)

This thesis reports on the manifestation of structural disorder on molecular transport and it consists of two parts. Part I discusses the relations between classical transport and the underlying structural complexity of the system. Both types of molecular diffusion, namely Gaussian and non-Gaussian are presented and the relevant time regimes are discussed. In addition the concept of structural universality is introduced and connected with the diffusion metrics. One of the most robust techniques for measuring molecular mean square displacements is magnetic resonance. This method requires encoding and subsequently reading out after an experimentally controlled time, a phase ϕ to the ...


Listening To Lasers: Photoacoustic Gas Sensing, Michael Hopkins 2016 Portland State University

Listening To Lasers: Photoacoustic Gas Sensing, Michael Hopkins

Student Research Symposium

Herein lies the makings of a sensor for gaseous materials due to the technique known as photo-acoustic spectroscopy. Whereby a gas filled metallic tube of known resonance has an impingement to its open aspect a beam of photons of known colour and at a specified rate such that the rate of incoming light corpuscles matches the natural standing wave frequency for the column of gas within said tube, to wit resonance. Through foresight of the molecular orbital theory and historic datums on the subject of infrared spectroscopy one naturally comes to the employment of absorbance transfiguring energy to kinetic motions ...


Intramembrane Congestion Effects On Lysenin Channel Voltage-Induced Gating, Eric Krueger, Sheenah Bryant, Nisha Shrestha, Tyler Clark, Charles Hanna, David Pink, Daniel Fologea 2016 Boise State University

Intramembrane Congestion Effects On Lysenin Channel Voltage-Induced Gating, Eric Krueger, Sheenah Bryant, Nisha Shrestha, Tyler Clark, Charles Hanna, David Pink, Daniel Fologea

Daniel Fologea

All cell membranes are packed with proteins. The ability to investigate the regulatory mechanisms of protein channels in experimental conditions mimicking their congested native environment is crucial for understanding the environmental physicochemical cues that may fundamentally contribute to their functionality in natural membranes. Here we report on investigations of the voltage-induced gating of lysenin channels in congested conditions experimentally achieved by increasing the number of channels inserted into planar lipid membranes. Typical electrophysiology measurements reveal congestion-induced changes to the voltage-induced gating, manifested as a significant reduction of the response to external voltage stimuli. Furthermore, we demonstrate a similar diminished voltage ...


The Evaluation And Implementation Of Magnetic Fields For Large Strain Uniaxial And Biaxial Cyclic Testing Of Magnetorheological Elastomers., Dave Gorman, Niall Murphy, Ray Ekins, Steve Jerrams 2016 School of Manufacturing and Design Engineering, Dublin Institute of Technology

The Evaluation And Implementation Of Magnetic Fields For Large Strain Uniaxial And Biaxial Cyclic Testing Of Magnetorheological Elastomers., Dave Gorman, Niall Murphy, Ray Ekins, Steve Jerrams

Articles

Magnetorheological Elastomers (MREs) are “smart” materials whose physical properties are altered by the application of magnetic fields. In previous studies the properties of MREs have been evaluated under a variety of conditions, however little attention has been paid to the recording and reporting of the magnetic fields used in these tests [1]. Currently there is no standard accepted method for specifying the magnetic field applied during MRE testing. This study presents a detailed map of a magnetic field applied during MRE tests as well as providing the first comparative results for uniaxial and biaxial testing under high strain fatigue test ...


Optical Analysis And Fabrication Of Micro And Nanoscale Plasmonically Enhanced Devices, Avery M. Hill 2016 University of Arkansas, Fayetteville

Optical Analysis And Fabrication Of Micro And Nanoscale Plasmonically Enhanced Devices, Avery M. Hill

Physics Undergraduate Honors Theses

Plasmonic nanostructures have been shown to act as optical antennas that enhance optical devices due to their ability to focus light below the diffraction limit of light and enhance the intensity of the incident light. This study focuses on computational electromagnetic (CEM) analysis of two devices: 1) GaAs photodetectors with Au interdigital electrodes and 2) Au thin-film microstructures. Experiments showed that the photoresponse of the interdigital photodetectors depend greatly on the electrode gap and the polarization of the incident light. Smaller electrode gap and transverse polarization give rise to a larger photoresponse. It was also shown that the response from ...


Thermal Analysis Of Borosilicate Glass For Its Biological Applications, Gregory Humble 2016 Southern Polytechnic State University

Thermal Analysis Of Borosilicate Glass For Its Biological Applications, Gregory Humble

Symposium of Student Scholars

Borosilicate glass doped with varying wt% of cerium oxide is investigated for biological applications. Thermal studies of each formulation were conducted using an SDT Q600 differential scanning calorimeter. 30mg samples of 350 - 425 μm particle size of each type of glass were heated to 1200°C in order to obtain the glass transition, crystallization, and melting temperatures. Samples were then heated to 900°C at several heating rates, ranging from 2°C/min to 100°C/min, then compared against each other as well as against an undoped borosilicate glass.


Quantum Mechanical Interference In The Field Ionization Of Rydberg Atoms, Jacob A. Hollingsworth 2016 Ursinus College

Quantum Mechanical Interference In The Field Ionization Of Rydberg Atoms, Jacob A. Hollingsworth

Physics and Astronomy Honors Papers

Rydberg atoms are traditionally alkali metal atoms with their valence electron excited to a state of very large principle quantum number. They possess exaggerated properties, and are consequently an attractive area of study for physicists. An example of their exaggerated properties is seen in their response to the presence of an applied electric field. In this work, we study the energy distribution of Rydberg atoms when subjected to a dynamic electric field intended to ionize them.

We excite 85Rb atoms to a superposition of the 46D5/2 |mj| = 1/2 and |mj| = 3/2 states in ...


Simulation Of Heterogeneous Colloidal Particles Immersed In Liquid Crystals, Setarehalsadat Changizrezaei 2016 The University of Western Ontario

Simulation Of Heterogeneous Colloidal Particles Immersed In Liquid Crystals, Setarehalsadat Changizrezaei

Electronic Thesis and Dissertation Repository

This thesis describes an investigation of interactions between colloidal particles immersed in a liquid crystal. The presence of colloidal particles in the liquid crystal distorts the director field distorted from its uniform orientation. These elastic distortions produce topological defects around the particles, which induce anisotropic interactions between them, and these anisotropic interactions can be used to manufacture non-closed packed colloidal crystals, such as diamond lattices, which are interesting in photonic applications. First, different types of liquid crystals, the mathematical tools to describe the anisotropic nature of liquid crystals, the Landau-de Gennes free-energy model to investigate the particle’s interaction, and ...


Isotope Effect On Electron-Phonon Interaction In Multiband Superconductor Mgb2, Adam Kaminski, Daixiang Mou, Paul C. Canfield, Serguei Budko, Lunan Huang, Valentin Taufour, Yun Wu, Soham Manni 2016 Ames Laboratory

Isotope Effect On Electron-Phonon Interaction In Multiband Superconductor Mgb2, Adam Kaminski, Daixiang Mou, Paul C. Canfield, Serguei Budko, Lunan Huang, Valentin Taufour, Yun Wu, Soham Manni

Ames Laboratory Datasets

We investigate the effect of isotope substitution on electron-phonon interaction in multi-band superconductor MgB$_2$ using tunable laser based Angle Resolved Photoemission Spectroscopy. The kink structure around 70 meV in Sigma band, which is caused by electron coupling to E_2g phonon mode, is shifted to higher binding energy by ~3.5 meV in Mg^10B2. The changes of the kink energy reported here suggest that the anharmonicity of the E2g phonon in MgB2 is very small, which reopens the debate about the unusually small isotope coefficient in this material. These results are the benchmark for investigation of isotope effect in ...


Up-Conversion Emissions Of Er3 Doped Gd2(Wo4)3 Phosphors, Grayson Wiggins 2016 Georgia Southern University

Up-Conversion Emissions Of Er3 Doped Gd2(Wo4)3 Phosphors, Grayson Wiggins

Georgia Southern University Research Symposium

Photon up-conversion is a luminescent process which changes incoming low energy light into a higher energy form of light, such as infrared into visible light. This process is very popular and applicable to TV displays, bio-labels, and solar cells. The work to be presented is about erbium's ability to convert infrared laser light in green light by photon up-conversion. The trivalent erbium is doped into gadolinium tungstate in order to research the efficiency and mechanisms involved in the up-conversion process. Although still currently being research, it has already shown promising results including low photon energies, economic synthesis, and naked-eye ...


Intramolecular Cross-Linking Of Beta Subunits And Pegylation Of Bovine Stroma Free Hemoglobin For Use As A Hemoglobin Based Oxygen Carrier, Gil Salazar 2016 Georgia Southern University

Intramolecular Cross-Linking Of Beta Subunits And Pegylation Of Bovine Stroma Free Hemoglobin For Use As A Hemoglobin Based Oxygen Carrier, Gil Salazar

Georgia Southern University Research Symposium

Purified Bovine Stroma-Free Hemoglobin's (BSFHb) two beta subunits where intramolecularly cross-linked (BXLHb) using bis(3,5-dibromosalicyl) fumarate (DBBF) and further modified with Polyethylene glycol (BPEGXLHb) for possible use as a Hemoglobin Based Oxygen Carrier (HBOC). Each stage of modification was characterized by size exclusion chromatography and fluorescence methods. We prepared several different molar ratios of DBBF and BSFHb to acquire the highest yield of BXLHb. Cross-linking of the beta subunits will stabilize the whole Hb tetramer from dissociation and prevent unwanted degradation of the HBOC. We prepared a sample modified with PEG (PEGylation) that had a molecular weight of ...


Role Of Diffusive, Photovoltaic, And Thermal Effects In Beam Fanning In Linbo3, Jaw-Jueh Liu, Partha P. Banerjee, Q. W. Song 2016 University of Alabama, Huntsville

Role Of Diffusive, Photovoltaic, And Thermal Effects In Beam Fanning In Linbo3, Jaw-Jueh Liu, Partha P. Banerjee, Q. W. Song

Partha Banerjee

We analyze the steady-state (Gaussian) beam fanning in LiNbO3 from the nonlinearly coupled Kukhtarev equations by including both diffusive and photovoltaic effects and by adding the thermal effect in the calculation. There is good agreement between theory and experiment. The results show a symmetric beam-fanning pattern whose size depends on the beam waist and the power. Possible applications of our results in nondestructive testing of material parameters and optical limiting are discussed.


Volume Holographic Optical Elements, Ching-Cherng Sun, Partha P. Banerjee 2016 National Central University

Volume Holographic Optical Elements, Ching-Cherng Sun, Partha P. Banerjee

Partha Banerjee

The final two papers are concerned with the analysis of novel holograms. Banerjee et al. investigate holographic recording and reconstruction for edge-lit holograms recorded in a 90-degree geometry. Various cases of recording and readout that incorporate propagational diffraction have been modeled. It is shown that the 90-degree geometry can result in beam shaping, as evidenced through preliminary experimental results with photorefractive lithium niobate. Nguyen et al. propose a new approach for designing computer-generated holograms. An artificial neural network is used to initiate the genetic algorithm so that the high computation cost of genetic algorithms for synthesizing holograms is significantly reduced ...


Achieving Enhanced Gain In Photorefractive Polymers By Eliminating Electron Contributions Using Large Bias Fields, C. M. Liebig, S. H. Buller, Partha P. Banerjee, S. A. Basun, Pierre-Alexandre Blanche, J. Thomas, Cory W. Christenson, N. Peyghambarian, Dean R. Evans 2016 Air Force Research Laboratory

Achieving Enhanced Gain In Photorefractive Polymers By Eliminating Electron Contributions Using Large Bias Fields, C. M. Liebig, S. H. Buller, Partha P. Banerjee, S. A. Basun, Pierre-Alexandre Blanche, J. Thomas, Cory W. Christenson, N. Peyghambarian, Dean R. Evans

Partha Banerjee

Photorefractive polymers have been extensively studied for over two decades and have found applications in holographic displays and optical image processing. The complexity of these materials arises from multiple charge contributions, for example, leading to the formation of competing photorefractive gratings. It has been recently shown that in a photorefractive polymer at relatively moderate applied electric fields the primary charge carriers (holes) establish an initial grating, followed by a subsequent competing grating (electrons) resulting in a decreased two-beam coupling and diffraction efficiencies. In this paper, it is shown that with relatively large sustainable bias fields, the two-beam coupling efficiency is ...


3d Visualization Using Pulsed And Cw Digital Holographic Tomography Techniques, George Nehmetallah, Partha P. Banerjee, D. Ferree, R. Kephart, Sarat C. Praharaj 2016 The Catholic University of America

3d Visualization Using Pulsed And Cw Digital Holographic Tomography Techniques, George Nehmetallah, Partha P. Banerjee, D. Ferree, R. Kephart, Sarat C. Praharaj

Partha Banerjee

We outline the use of digital holographic tomography to determine the three-dimensional (3D) shapes of falling and static objects, such as lenslets and water droplets. Reconstruction of digitally recorded inline holograms is performed using multiplicative and Radon transform techniques to reveal the exact 3D shapes of the objects.


Dynamical Spacetime Symmetry, Benjamin Lovelady, James Thomas Wheeler 2016 Utah State University

Dynamical Spacetime Symmetry, Benjamin Lovelady, James Thomas Wheeler

Physics Student Research

According to the Coleman-Mandula theorem, any gauge theory of gravity combined with an internal symmetry based on a Lie group must take the form of a direct product in order to be consistent with basic assumptions of quantum field theory. However, we show that an alternative gauging of a simple group can lead dynamically to a spacetime with compact internal symmetry. The biconformal gauging of the conformal symmetry of n-dimensional Euclidean space doubles the dimension to give a symplectic manifold. Examining one of the Lagrangian submanifolds in the flat case, we find that in addition to the expected SO(n ...


Wormholes - Gates To The Stars?, Samuel Shreeve, Jim Wheeler 2016 Utah State University

Wormholes - Gates To The Stars?, Samuel Shreeve, Jim Wheeler

Research Week

One of the most consistently fascinating results of Albert Einstein’s theory of general relativity is the prediction of wormholes – astronomical objects which are, among other things, capable of serving as a connection between two distant regions of space. The simplest class of wormholes are Schwarzschild wormholes – wormholes that behave as non-rotating, non-charged black holes, except that the event horizon serves as a connection to another wormhole elsewhere, instead of a point of no return.

This research presentation analyzes the attributes that make a Schwarzschild wormhole unsuitable for human travel, and examines the conditions that would have to hold for ...


Nucleosynthesis In Core-Collapse Supernovae, Rachel E Mersch 2016 University of Tennessee, Knoxville

Nucleosynthesis In Core-Collapse Supernovae, Rachel E Mersch

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

A Core-Collapse Supernova explosion occurs when nuclear fusion stops in the core of a massive star. Without a source of energy supplying enough pressure to balance gravity, the core becomes unstable and collapses to form a neutron star. Beyond the neutron star, a shockwave forms which moves outward through the star, causing heavier elements to be created through nuclear fusion. We have been studying the elements that are ejected from a Core-Collapse Supernova using a nuclear code network called XNet, which follows the thermonuclear kinetics. We use the results from a code called Chimera, which explores the mechanism of Core-Collapse ...


Uv Degradation Effects: Terrestrial Versus Space Environment, Katie Gamaunt, Krysta Moser, Alex Souvall, JR Dennison 2016 Utah State University

Uv Degradation Effects: Terrestrial Versus Space Environment, Katie Gamaunt, Krysta Moser, Alex Souvall, Jr Dennison

Posters

The decrease in visible and ultraviolet transmission spectra of polymeric and glass spacecraft materials has been measured to determine the extent of degradation due to high energy UV radiation similar to the solar spectrum (both above and below the stratosphere). This project looked at the effects that the atmosphere has in regards to blocking UV radiation and thus, slowing down the UV degradation process. Materials such as quartz, borosilicate glass, sodium glasses, polyethylene, polyimide, and polyethylene terephthalate polymers were exposed to radiation from a focused high intensity deuterium lamp source, which generates radiation in the UVA and UVB spectrum. Duplicates ...


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