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Effective Tuning Of Bimetallic Composition Of Gold-Copper Nanomolecules And The Emergence Of Plasmon-Like Feature In Optical Spectra, Asantha Champika Dharmaratne Jan 2015

Effective Tuning Of Bimetallic Composition Of Gold-Copper Nanomolecules And The Emergence Of Plasmon-Like Feature In Optical Spectra, Asantha Champika Dharmaratne

Electronic Theses and Dissertations

Au144-xCux(SR)60 alloy nanomolecules were synthesized and characterized by using ESI-MS to atomic precision. A maximum of 23 copper atoms replace the gold atoms; when the number of copper atoms is higher than eight, a surface plasmon-like peak appears at ∼520 nm. Based on the fundamental, elemental properties of Au and Cu, we predict a mixed atomic ordering and incorporation into the Au12 and Au 42 shells of the proposed icosahedral structured model. Alloy nanomolecules reported here could have potential applications in the field of catalysis and optical sensors.


Method Development For Mass Spectrometric Characterization Of Ultra-Small Nanomolecules And Mass Spectrometry Imaging Of Selected Biomolecules, Nuwan K. Kothalawala Jan 2015

Method Development For Mass Spectrometric Characterization Of Ultra-Small Nanomolecules And Mass Spectrometry Imaging Of Selected Biomolecules, Nuwan K. Kothalawala

Electronic Theses and Dissertations

High sensitivity, selectivity and remarkable identification capabilities facilitate the applicability of mass spectrometry (MS) in diverse fields. This dissertation outlines how this cutting edge technology is used to determine the chemical composition of the ultra-small nanomolecules (NMs) to atomic precision and obtain spatial resolution of selected biomolecules using mass spectrometry imaging (MSI). Chapter I includes introduction to electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) MS used in my PhD research. Chapter II explains how high resolution ESI-MS methods were developed to analyze the polar water-soluble NMs. These new methods express how ESI-MS parameters need to be optimized …


Power And Hotspot Modeling For Modern Gpus, Md Mainul Hassan Jan 2015

Power And Hotspot Modeling For Modern Gpus, Md Mainul Hassan

Electronic Theses and Dissertations

As General Purpose GPUs (GPGPU) are increasingly becoming a prominent component of high performance computing platforms, power and thermal dissipation are getting more attention. The trade-offs among performance, power, and heat must be well modeled and evaluated from the early stage of GPU design. This necessitates a tool that allows GPU architects to quickly and accurately evaluate their design. There are a few models for GPU power but most of them estimate power at a higher level than architecture, which are therefore missing hardware reconfigurability. In this thesis, we propose a framework that models power and heat dissipation at the …


The Least Prime Number That Splits Completely In S3-Sextic Number Fields, Zhenchao Ge Jan 2015

The Least Prime Number That Splits Completely In S3-Sextic Number Fields, Zhenchao Ge

Electronic Theses and Dissertations

In number theory, an integer n is quadratic residue modulo an odd prime p if n is congruent to a perfect square modulo p. Otherwise, n is is called a quadratic nonresidue. Bounding the least prime quadratic residue and the least quadratic nonresidue are two very classical problems in number theory. These classical problems can be generalized to any number field K by asking for bounds the least for prime that splits completely or does not split completely, respectively, in the ring of integers of K. The goal of this thesis is to bound the least prime that splits completely …


Microtremor Recordings In Northern Mississippi: Evaluating Site Effect And Correlating With Wave Climate, Zhen Guo Jan 2015

Microtremor Recordings In Northern Mississippi: Evaluating Site Effect And Correlating With Wave Climate, Zhen Guo

Electronic Theses and Dissertations

Site effects is considered as one of the main reasons that cause enormous damages in earthquakes and it is mainly controlled by the local geological condition. The main research area, Northern Mississippi, is located in Mississippi Embayment (ME) where is mainly composed of unconsolidated sediments which can be as thick as 1400m along the Mississippi River floodplain, and is favorable to have significant site effects. Meanwhile Northern Mississippi is also located in the moderate to heavy potential damage area of the New Madrid Seismic Zone, which is in the northern section of ME. Therefore, it is very necessary to evaluate …


Specification And Mechanical Verification Of Performance Profiles Of Software Components, Nighat Yasmin Jan 2015

Specification And Mechanical Verification Of Performance Profiles Of Software Components, Nighat Yasmin

Electronic Theses and Dissertations

Software performance predictability is vital to a system design and unpredictable performance is a leading cause of software failure. The emphasis of this dissertation is on verification that component-based software performs as specified. Performance profiles (specifications) depend on functional specifications and are necessary for all components for modular verification. Modular verification process is scalable because it uses profiles as contracts and allows verification of a single component in isolation with the assumption that any underlying component would have already been verified or will be verified to meet its specifications independently. This dissertation presents an integration of performance specification (profiles) with …


Complex Vector Lattices: Tensor Products And Multilinear Maps, Christopher Michael Schwanke Jan 2015

Complex Vector Lattices: Tensor Products And Multilinear Maps, Christopher Michael Schwanke

Electronic Theses and Dissertations

In this thesis, we study completions of Archimedean real vector lattices relative to any nonempty set of continuous positively homogeneous functions defined on Rn. Examples of such completions include square mean closed vector lattices and geometric mean closed vector lattices. These functional completions lead to a vector lattice complexification of any Archimedean real vector lattice. Unlike the vector space complexification of an Archimedean real vector lattice, the vector lattice complexification always results in an Archimedean complex vector lattice. For example, we prove that the vector space complexification of the Fremlin tensor product C(X)⊗C(Y) is not a complex vector lattice when …


Gold Nanomolecules : Developing Synthetic Protocols, Characterization And Investigation Of Ligand Effects On Structure And Properties, Praneeth Reddy Nimmala Jan 2015

Gold Nanomolecules : Developing Synthetic Protocols, Characterization And Investigation Of Ligand Effects On Structure And Properties, Praneeth Reddy Nimmala

Electronic Theses and Dissertations

The term "Nano" in chemistry refers to particles/molecules in the size range 1 to 100 nm. Gold nanoparticles were used in ancient times in making decorative glass as they produce vibrant, size dependent, colors upon interaction with light. Gold is a preferred choice of metal for the synthesis of nanoparticles mainly due to its inertness to atmospheric conditions and most chemicals. Gold thiolate nanomolecules, which is the primary focus of this dissertation research, are chemical molecules with a fixed number of gold atoms and organo-thiolate ligands. They are of the form Aux(SR)y and possess molecule-like properties as a result of …


Semi-Leptonic Decay Of Lambda-B In The Standard Model And With New Physics, Wanwei Wu Jan 2015

Semi-Leptonic Decay Of Lambda-B In The Standard Model And With New Physics, Wanwei Wu

Electronic Theses and Dissertations

Heavy quark decays provide a very advantageous investigation to test the Standard Model (SM). Recently, promising experiments with b quark, as well as the analysis of the huge data sets produced at the B factories, have led to an increasing study and sensitive measurements of relative b quark decays. In this thesis, I calculate various observables in the semi-leptonic decay process Λb → Λ cτν[special character omitted]τ both in the SM and in the presence of New Physics (NP) operators with different Lorentz structures. The results are relevant for the coming measurement of this semi-leptonic decay at LHC b experiment …


Accurate Computation Of Molecular Properties From Novel Applications Of Quantum Mechanical Wavefunction Methods, James Coleman Howard Jan 2015

Accurate Computation Of Molecular Properties From Novel Applications Of Quantum Mechanical Wavefunction Methods, James Coleman Howard

Electronic Theses and Dissertations

High-accuracy quantum mechanical (qm) wavefunction methods have been applied to compute molecular properties of weakly-bound clusters. This work focuses on both extending the applicability of robust theoretical methods to larger systems and also determining the inherent accuracy of ab initio methods when compared to experimentally measured properties. Described here is the development of an efficient many-body approach that offers the ability to reduce both the time and the computational resources normally required to compute these properties reliably. The n-body:many-body qm:qm technique has been extended to compute harmonic vibrational frequencies of clusters. Applying this methodology to small hydrogen-bonded clusters demonstrates that …


Progress Toward The Total Synthesis Of The Natural Product Herbicide Ascaulitoxin Aglycone, Jeffery Brian Morgan Jan 2015

Progress Toward The Total Synthesis Of The Natural Product Herbicide Ascaulitoxin Aglycone, Jeffery Brian Morgan

Electronic Theses and Dissertations

Ascaulitoxin aglycone is a structurally unique bis-amino acid isolated from the fungal species Ascochyta caulina, with herbicidal activity against Chenopodium album. Ascaulitoxin aglycone's potent herbicidal activity coupled with an unknown but novel mechanism of action makes it a perfect candidate for further study in the pursuit of new natural product herbicides. This dissertation research will illustrate three synthetic strategies towards the total synthesis of ascaulitoxin aglycone from chiral pool building blocks. Strategy 1 invokes the use of the Henry reaction as a key step for the construction of the central C4-C5 cis-aminohydroxy group, which was moderately successful, but abandoned in …


Gini Covariance Matrix And Its Affine Equivariant Version, Lauren Anne Weatherall Jan 2015

Gini Covariance Matrix And Its Affine Equivariant Version, Lauren Anne Weatherall

Electronic Theses and Dissertations

Gini's mean difference (GMD) and its derivatives such as Gini index have been widely used as alternative measures of variability over one century in many research fields especially in finance, economics and social welfare. In this dissertation, we generalize the univariate GMD to the multivariate case and propose a new covariance matrix so called the Gini covariance matrix (GCM). The extension is natural, which is based on the covariance representation of GMD with the notion of multivariate spatial rank function. In order to gain the affine equivariance property for GCM, we utilize the transformation-retransformation (TR) technique and obtain TR version …


Biomolecular Folding Rates As Understood From Single-Reaction-Coordinate Langevin Dynamics And Kramers’ Theory, Md Adnan Kabir Jan 2015

Biomolecular Folding Rates As Understood From Single-Reaction-Coordinate Langevin Dynamics And Kramers’ Theory, Md Adnan Kabir

Electronic Theses and Dissertations

Langevin dynamics was used to model the folding and unfolding of simple, hairpin-like biomolecules whose ends are attached to laser-trapped beads, as occurs in optical tweezers experiments. The Langevin process was evolved numerically, using parameters motivated by real experimental systems. Folding trajectories were generated and analyzed to extract the folding rate as a function of the force applied to the beads. The observed rate was compared to the analytical predictions of Kramers' theory. Strong discrepancies were noted. The failure of the Kramers' theory was attributed to the slow dynamical response of the beads, which it does not account for. The …


Effect Of Accelerated Global Expansion On Bending Of Light, Mir Emad Aghili Jan 2015

Effect Of Accelerated Global Expansion On Bending Of Light, Mir Emad Aghili

Electronic Theses and Dissertations

No abstract provided.


Acousto-Electric Impedance Of Ferroelectric Phononic Superlattice, Ola Hassan Nusierat Jan 2015

Acousto-Electric Impedance Of Ferroelectric Phononic Superlattice, Ola Hassan Nusierat

Electronic Theses and Dissertations

The Acousto-Electric Impedance z of a Ferroelectric Phononic Superlattice (fps) is investigated. The analytical derivation of z and its phase reveal that both are functions of physical parameters such as the electromechanical coupling coefficient, the mechanical quality factor, the domain length and the phase velocity of the plate acoustic waves (paw). Mathematical code is produced that allows for modeling z in a two dimensional fps. It is observed that z depends on the number of domains in the fps structure. Fewer domains in the structure might minimize z or make it approach zero at certain conditions. A series of experiments …


The Spectroscopic Characterization Of Newly Developed Emissive Materials And The Effects Of Environment On Their Photophysical Properties, Louis Edward Mcnamara Jan 2015

The Spectroscopic Characterization Of Newly Developed Emissive Materials And The Effects Of Environment On Their Photophysical Properties, Louis Edward Mcnamara

Electronic Theses and Dissertations

The development of new materials capable of efficient charge transfer and energy storage has become increasingly important in many areas of modern chemical research. This is especially true for the development of emissive optoelectronic devices and in the field of solar to electric energy conversion. The characterization of the photophysical properties of new molecular systems for these applications has become critical in the design and development of these materials. Many molecular building blocks have been developed and understanding the properties of these molecules at a fundamental level is essential for their successful implementation and future engineering. This dissertation focuses on …


Design And Implementation Of Fast Motion Estimation In Modern Video Compression On Gpu, Zhaohua Yi Jan 2015

Design And Implementation Of Fast Motion Estimation In Modern Video Compression On Gpu, Zhaohua Yi

Electronic Theses and Dissertations

Motion estimation is the most compute expensive part of high definition video compression. It accounts for more than 50\% of overall execution. Therefore, improving the performance of motion estimation can make significant impact on the overall performance of video compression. The performance of motion estimation can be improved in two aspects: algorithm and implementation. This thesis touches both aspects. We first propose an innovative motion estimation algorithm by replacing the traditional block matching method which comparing blocks pixel by pixel with a brand new method which based on lbp (local binary pattern) code. Our new method first encodes the original …


Mercury Methylation Potentials In Sediments An Ancient Cypress Wetland Using Species-Specific Isotope Dilution-Gc-Icp-Ms: Analytical Method Development And The Effect Of Sorbent Amendments, Derek Davin Bussan Jan 2015

Mercury Methylation Potentials In Sediments An Ancient Cypress Wetland Using Species-Specific Isotope Dilution-Gc-Icp-Ms: Analytical Method Development And The Effect Of Sorbent Amendments, Derek Davin Bussan

Electronic Theses and Dissertations

A novel method was developed to measure mercury (Hg) directly in environmental solids using inductively coupled plasma mass spectrometry (ICP-MS) with online sample ashing. The method combines a direct mercury analyzer (DMA) that is based on sample combustion, Hg pre-concentration by amalgamation with gold, and atomic absorption spectrometry (AAS), with a high resolution ICP-MS. Unlike AAS, the ICP-MS is capable of individual isotope measurements allowing for accurate quantitation by isotope dilution mass spectrometry (IDMS) and for isotope tracer experiments. The method was validated using certified reference materials including sediment (NIST 2709), leaves (NIST 1547), and fish-muscle (DORM-3), with recoveries within …


Functional Reactive Programming For Games, Peter Adewunmi Salu Jan 2015

Functional Reactive Programming For Games, Peter Adewunmi Salu

Electronic Theses and Dissertations

We investigate the effectiveness of functional reactive programming for games. To accomplish this, we clone aa, an existing game, in Elm, a purely functional programming language. We find that functional reactive programming offers an excellent alternative to event driven programming in purely functional languages. Elm still needs more work if it aims to compete with JavaScript libraries. Games, which typically need several inputs at the same time, benefit from the first class status of Signals, which allow them to be combined.


Identifying A Mechanism For An Infiltration Threshold From The Sunflower River, Ms To The Underlying Alluvial Aquifer, Austin Cole Patton Jan 2015

Identifying A Mechanism For An Infiltration Threshold From The Sunflower River, Ms To The Underlying Alluvial Aquifer, Austin Cole Patton

Electronic Theses and Dissertations

Long-term groundwater level and stream stage measurements at a USGS coupled groundwater stream-gaging station located on the Sunflower River in Sunflower, MS show an apparent stage-threshold for infiltration to the underlying alluvial aquifer. This site is located near the center of a large regional groundwater cone of depression in the Mississippi River Valley alluvial aquifer. The USGS well (termed well 3 in this study) was thought to be completed in the regional shallow aquifer, though often recording anomalously high water levels relative to other wells in the region. The purpose of this research was to identify the responsible mechanism for …


Fscan Code Development For Advanced Ligo Detector Characterization, Cody Arceneaux Jan 2015

Fscan Code Development For Advanced Ligo Detector Characterization, Cody Arceneaux

Electronic Theses and Dissertations

The Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) is an experiment designed to provide direct detection of gravitational waves. Its searches for periodic gravitational waves are highly susceptible to long-duration noise that appears as spectral lines. FScan is a tool for finding spectral lines and is used to identify the lines that appear in the gravitational-wave data; it is also used to characterize LIGO's detectors. This thesis details work in rewriting the plotting portion of FScan, making improvements to the FScan driver script, and writing code to assist in the tracking of wandering spectral lines. In particular, this thesis presents the …


Testing Lepton Nonuniversality In Tau Neutrino Scattering, Hongkai Liu Jan 2015

Testing Lepton Nonuniversality In Tau Neutrino Scattering, Hongkai Liu

Electronic Theses and Dissertations

Recently hints of lepton flavor non-universality emerged in the BaBar and LHCb experiments. In this paper we propose tests of lepton universality in scattering. To parametrize the new physics we adopt an effective Lagrangian approach and consider the neutrino deep inelastic scattering processes tau neutrino+nucleon to tau + X and muon neutrino+nucleon to muon + X where we assume the largest new physics effects are in the tau sector. We also consider an explicit leptoquark model in our calculations. In order to make comparison with the standard model and also in order to cancel out the uncertainty of the parton …


Wind Induced Ground Motion, Vahid Naderyan Jan 2015

Wind Induced Ground Motion, Vahid Naderyan

Electronic Theses and Dissertations

Wind noise is a problem in seismic surveys and can mask the seismic signals at low frequency. Development of practical solutions to this problem must be based on a good understanding of the mechanism of the wind-ground coupling. This thesis investigates the driving pressure and shear stress perturbations on the ground surface associated with wind-induced ground motions. A prediction of the ground displacements spectra from the measured ground properties and predicted pressure and shear stress at the ground surface is developed. Field measurements are conducted at a site in Marks, MS, having a flat terrain and low ambient seismic noise …


Diagonals Of Tensor Products Of Banach Lattices With Bases., Byunghoon Lee Jan 2015

Diagonals Of Tensor Products Of Banach Lattices With Bases., Byunghoon Lee

Electronic Theses and Dissertations

In this dissertation, we investigate diagonals of tensor products of Banach lattices with bases. We first consider questions on the positive tensor products of l_p spaces. We characterize the main diagonals of the positive projective tensor product and the positive injective tensor product of l_p space. Then by using these two main diagonals, we characterize the reflexivity, the property of being Kantorovich - Banach spaces, and the property of being order continuous of n-fold positive projective and positive injective tensor products of l_p spaces. Next, we consider the diagonals of injective tensor product of Banach lattices with bases. Let E …


Synthetic Study Of Karlotoxins And Investigation Of Alpha-Diaminoboryl Carbanion Chemistry, Yusuke Takahashi Jan 2015

Synthetic Study Of Karlotoxins And Investigation Of Alpha-Diaminoboryl Carbanion Chemistry, Yusuke Takahashi

Electronic Theses and Dissertations

Karlotoxins (KmTxs), produced by a toxic marine/estuarine phytoplankton, the dinoflagellate Karlodinium veneficum, are known to be ichthyotoxic, thus being associated with numerous fish deaths events worldwide. They have also been reported to show a variety of biological activities such as hemolytic, cytotoxic, and anti-fungal activities. Recently, the Hamann group successfully assigned the absolute configurations of KmTx2, the first complete structure elucidation among the congeners. In a structural sense, karlotoxins are a family of linear polyketides with three distinctive regions; a bis-tetrahydropyran core fragment, a long, highly oxygenated carbon chain, and a lipophilic chlorodiene unit. Such potent biological activities as well …


Efficient Utilization Of Solar Energy In Dye-Sensitized Solar Cells And In The Photocatalytic Reduction Of Carbon Dioxide, Aron Joel Huckaba Jan 2015

Efficient Utilization Of Solar Energy In Dye-Sensitized Solar Cells And In The Photocatalytic Reduction Of Carbon Dioxide, Aron Joel Huckaba

Electronic Theses and Dissertations

One of the most important questions humanity will face in the next 100 years is going to be "What will happen when oil runs out?" This dissertation describes efforts to utilize solar energy to improve renewable energy technology in two ways: First, through the improvement of dye sensitized solar cells by theimprovement of D-π-A dye subunits, the development of practical sensitizers, and progress towards stable, tunable redox shuttles. A novel indolizine donor subunit was synthesized that was shown to be the strongest reported donor. Dyes made from this novel donor and devices using the Γ-/I 3- reached up to 5.4% …