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Synthesis And Characterization Of Monolayer Protected Gold Nanoparticles And A Gold-Titanium Dioxide Nanocomposite Intended For Photocatalytic Degradation Of Environmental Pollutants, Piyadarsha Amaratunga 2010 Western Michigan University

Synthesis And Characterization Of Monolayer Protected Gold Nanoparticles And A Gold-Titanium Dioxide Nanocomposite Intended For Photocatalytic Degradation Of Environmental Pollutants, Piyadarsha Amaratunga

Dissertations

Semiconductor and metal clusters in the nanometer size regime display interesting optical, electronic and chemical properties that are size dependant. Highly monodisperse gold nanoparticles of different sizes have been synthesized and isolated by newly developed methodologies, using tiopronin as the capping ligand. Titanium dioxide nanoparticles (Ti02) have been used as the photocatalytic center and gold nanoparticles have been attached on Ti02 to make a nanocomposite. According to the findings, gold nanoparticles play a vital role in enhancing the photocatalytic activity of Ti02, by facilitating the charge separation. Further, the photocatalytic activity also can be tuned by changing ...


Surface And Subsurface Structures Of The Western Valley And Ridge In Tennessee And Geometry And Kinematics That Permit Reconstruction Of The Tennessee Salient, Southern Appalachians, Jennifer Kathleen Whisner 2010 University of Tennessee - Knoxville

Surface And Subsurface Structures Of The Western Valley And Ridge In Tennessee And Geometry And Kinematics That Permit Reconstruction Of The Tennessee Salient, Southern Appalachians, Jennifer Kathleen Whisner

Doctoral Dissertations

The southern and central Appalachian foreland fold-thrust belt comprises a series of orogen -scale curves that extend from Alabama to New York. One of these is the Tennessee salient, a foreland-convex curve that extends from Cartersville, Georgia, to Roanoke, Virginia. Development of a kinematic model for deformation in the salient has been hindered by a paucity of penetrative deformation in this generally low temperature, low volume-loss portion of the orogen.

Industry seismic reflection lines provide greater resolution of subsurface geometry of both the basement surface and the overlying fold-thrust belt, confirming some previous interpretations and changing others. A series of ...


Reconstruction And Analysis Of The Chukchi Sea Circulation In 1990-1991, Gleb Panteleev, Dmitri A. Nechaev, Andrey Proshutinsky, R. Woodgate, J. Zhang 2010 University of Alaska

Reconstruction And Analysis Of The Chukchi Sea Circulation In 1990-1991, Gleb Panteleev, Dmitri A. Nechaev, Andrey Proshutinsky, R. Woodgate, J. Zhang

Faculty Publications

The Chukchi Sea (CS) circulation reconstructed for September 1990 to October 1991 from sea ice and ocean data is presented and analyzed. The core of the observational data used in this study comprises the records from 12 moorings deployed in 1990 and 1991 in U. S. and Russian waters and two hydrographic surveys conducted in the region in the fall of 1990 and 1991. The observations are processed by a two-step data assimilation procedure involving the Pan-Arctic Ice-Ocean Modeling and Assimilation System (employing a nudging algorithm for sea ice data assimilation) and the Semi-implicit Ocean Model [utilizing a conventional four-dimensional ...


Nam Model Forecasts Of Warm Season Quasi-Stationary Frontal Environments In The Central U.S., Shih-Yu (Simon) Wang, Adam J. Clark 2010 Utah State University

Nam Model Forecasts Of Warm Season Quasi-Stationary Frontal Environments In The Central U.S., Shih-Yu (Simon) Wang, Adam J. Clark

Plants, Soils, and Climate Faculty Publications

Using a composite procedure, North American Mesoscale Model (NAM) forecast and observed environments associated with zonally oriented, quasi-stationary surface fronts for 64 cases during July–August 2006–08 were examined for a large region encompassing the central United States. NAM adequately simulated the general synoptic features associated with the frontal environments (e.g., patterns in the low-level wind fields) as well as the positions of the fronts. However, kinematic fields important to frontogenesis such as horizontal deformation and convergence were overpredicted. Surface-based convective available potential energy (CAPE) and precipitable water were also overpredicted, which was likely related to the overprediction ...


Atmospheric Scale Interaction On Wintertime Intermountain West Low-Level Inversions, Robert R. Gillies, Shih-Yu (Simon) Wang, Marty R. Booth 2010 Utah State University

Atmospheric Scale Interaction On Wintertime Intermountain West Low-Level Inversions, Robert R. Gillies, Shih-Yu (Simon) Wang, Marty R. Booth

Plants, Soils, and Climate Faculty Publications

Persistent winter inversions result in poor air quality in the Intermountain West of the United States. Although the onset of an inversion is relatively easy to predict, the duration and the subsequent breakup of a persistent inversion event remains a forecasting challenge. For this reason and for this region, historic soundings were analyzed for Salt Lake City, Utah, with reanalysis and station data to investigate how persistent inversion events are modulated by synoptic and intraseasonal variabilities. The results point to a close linkage between persistent inversions and the dominant intraseasonal (30 day) mode that characterizes the winter circulation regime over ...


Cfs Prediction Of Winter Persistent Inversions In The Intermountain Region, Robert R. Gillies, Shih-Yu (Simon) Wang, Jin Ho Yoon, Scott Weaver 2010 Utah State University

Cfs Prediction Of Winter Persistent Inversions In The Intermountain Region, Robert R. Gillies, Shih-Yu (Simon) Wang, Jin Ho Yoon, Scott Weaver

Plants, Soils, and Climate Faculty Publications

A recent study by Gillies and others of persistent inversion events in the Intermountain West of the United States found a substantive linkage between the intraseasonal oscillation (ISO) and the development of persistent inversion events. Given that NCEP’s Climate Forecast System (CFS) has demonstrated skill in the prediction of the ISO as far out as 1 month, it was decided to examine the CFS forecast’s capability in the prediction of such winter persistent inversions. After initial analysis, a simple regression scheme is proposed that is coupled to the CFS output of geopotential height as a way to predict ...


Windows Azure: Using Windows Azure's Service Bus To Solve Data Security Issues, Don Chambers 2010 Columbus State University

Windows Azure: Using Windows Azure's Service Bus To Solve Data Security Issues, Don Chambers

Theses and Dissertations

Many of the largest technology companies are heavily investing in Cloud Computing technology, making this a major force in the realm of software development. However, this software paradigm brings with it significantdata related security issues. This paper discusses some of these security issues and presents a solution. The solution calls for storing data outside of the cloud, and under the control of the cloud consumer. In addition, the solution provides the ability to manipulate data using only the standard HTTP ports that are typically opened at most locations. This solution is implemented using Microsoft's Windows Azure Cloud Computing operating ...


Gold Nanoparticle - Modified Zinc Oxide Nanoparticles As Novel Photocatalytic Materials, Nayane Udawatte 2010 Western Michigan University

Gold Nanoparticle - Modified Zinc Oxide Nanoparticles As Novel Photocatalytic Materials, Nayane Udawatte

Dissertations

The current study entails the construction of a novel nano-composite catalyst based on ZnO and Au nanoparticles and demonstrates its distinctive photocatalytic characteristics. Monodisperse gold nanoparticles (GNPs) passivated with monolayers of tiopronin or glutathione were synthesized via facile methods, and they were assembled on ZnO nanoparticles to form the nanocatalyst.

Steady state and time resolved photoluminescent studies on the nanocomposite revealed interesting charge transfer characteristics within the nanocomposite. Enhanced photooxidation of rhodamine 6G was observed for the nano-composite over bare ZnO, and modulation of photoactivity with the extent of GNP loading was illustrated. Photoreduction of thionine over the nanocomposite was ...


Simsight: A Virtual Machine Based Dynamic Call Graph Generator, Xueling Chen 2010 University of Nebraska at Lincoln

Simsight: A Virtual Machine Based Dynamic Call Graph Generator, Xueling Chen

Computer Science and Engineering: Theses, Dissertations, and Student Research

One problem with using component-based software development approach is that once software modules are reused over generations of products, they form legacy structures that can be challenging to understand, making validating these systems difficult. Therefore, tools and methodologies that enable engineers to see interactions of these software modules will enhance their ability to make these software systems more dependable. To address this need, we propose SimSight, a framework to capture dynamic call graphs in Simics, a widely adopted commercial full-system simulator. Simics is a software system that simulates complete computer systems. Thus, it performs nearly identical tasks to a real ...


Jvm-Based Techniques For Improving Java Observability, Peng Du 2010 University of Nebraska at Lincoln

Jvm-Based Techniques For Improving Java Observability, Peng Du

Computer Science and Engineering: Theses, Dissertations, and Student Research

Observability measures the support of computer systems to accurately capture, analyze, and present (collectively observe) the internal information about the systems. Observability frameworks play important roles for program understanding, troubleshooting, performance diagnosis, and optimizations. However, traditional solutions are either expensive or coarse-grained, consequently compromising their utility in accommodating today’s increasingly complex software systems. New solutions are emerging for VM-based languages due to the full control language VMs have over program executions. Existing such solutions, nonetheless, still lack flexibility, have high overhead, or provide limited context information for developing powerful dynamic analyses. In this thesis, we present a VM-based infrastructure ...


High Temperature Rare Earth Compounds: Synthesis, Characterization And Applications In Device Fabrication, Joseph R. Brewer 2010 University of Nebraska - Lincoln

High Temperature Rare Earth Compounds: Synthesis, Characterization And Applications In Device Fabrication, Joseph R. Brewer

Student Research Projects, Dissertations, and Theses - Chemistry Department

As the area of nanotechnology continues to grow, the development of new nanomaterials with interesting physical and electronic properties and improved characterization techniques are several areas of research that will be remain vital for continued improvement of devices and the understanding in nanoscale phenomenon. In this dissertation, the chemical vapor deposition synthesis of rare earth (RE) compounds is described in detail. In general, the procedure involves the vaporization of a REClx (RE = Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho) in the presence of hydride phase precursors such as decaborane and ammonia at high temperatures and low pressures ...


Theoretical And Experimental Studies In Nuclear Magnetic Resonance, Adrienne M. Roehrich 2010 University of Nebraska at Lincoln

Theoretical And Experimental Studies In Nuclear Magnetic Resonance, Adrienne M. Roehrich

Student Research Projects, Dissertations, and Theses - Chemistry Department

Nuclear magnetic resonance (NMR) is a tool used to probe the physical and chemical environments of specific atoms in molecules. This research explored small molecule analogues to biological materials to determine NMR parameters using ab initio computations, comparing the results with solid-state NMR measurements. Models, such as dimethyl phosphate (DMP) for oligonucleotides or CuCl for the active site of the protein azurin, represented computationally unwieldy macromolecules. 31P chemical shielding tensors were calculated for DMP as a function of torsion angles, as well as for the phosphate salts, ammonium dihydrogen phosphate (ADHP), diammonium hydrogen phosphate, and magnesium dihydrogen phosphate. The ...


Controlling Reductive Elimination From Novel I(Iii) Salts Using A Secure Method, Joseph W. Graskemper 2010 University of Nebraska at Lincoln

Controlling Reductive Elimination From Novel I(Iii) Salts Using A Secure Method, Joseph W. Graskemper

Student Research Projects, Dissertations, and Theses - Chemistry Department

Positron Emission Tomography (PET) is a valuable clinical, research, and diagnostic technique for human and animal organ imaging. The current market for PET in the United States is $500 million per year and is projected to be $5.4 billion per year globally by 2015. To synthesize labeled radiotracers, we are most interested in using 18F as the isotope of choice because it is a nearly ideal positron emitting radionuclide.

Electron-rich aromatic substrates can be particularly difficult to fluorinate. We show that reductive elimination of I(III) diaryliodonium salts provide increased fluorination of electron-rich aromatic substrates. Modest yields of ...


Reducing The Risk Of Human Exposure To Wildlife Diseases, Tyler A. Campbell 2010 USDA/APHIS/WS National Wildlife Research Center

Reducing The Risk Of Human Exposure To Wildlife Diseases, Tyler A. Campbell

USDA National Wildlife Research Center - Staff Publications

As a professional biologist working for a government agency, I am required to carry a card alerting medical personnel that I may have been exposed to certain zoonotic diseases (animal diseases that can infect man) not routinely considered in differential diagnosis. Some of these pathogens are obscure and seldom heard of, such as monkeypox and Q fever; others more commonly make headlines, such as influenza, West Nile virus, Lyme disease, and Hantavirus Pulmonary Syndrome. Hunters, ranchers, and biologists who work with wildlife have an increased risk of acquiring these diseases directly from animal hosts or their parasites. Here are some ...


On-Metal Synthesis Of Some Aryl Substituted Rhenium Η5 Cyclopenta[C] Pyridazyl Complexes, Phenahas Gandu Sriramulu 2010 Western Kentucky University

On-Metal Synthesis Of Some Aryl Substituted Rhenium Η5 Cyclopenta[C] Pyridazyl Complexes, Phenahas Gandu Sriramulu

Masters Theses & Specialist Projects

Heterocyclic organic and organometallic compounds (e.g. polypyrrole) and their derivatives have been of great interest for conductive polymers due to their novel properties and environmental stability as compared to non-aromatic analogs (e.g. polyacetylene). We are interested in synthesizing organometallic pyridazines and rhenium pyridazyl complexes for polymer research. SeveraI5,6-fused ring pyridazines (1,2-CsH3(CRNH)(CRN) have been synthesized and characterized. Additionally, pyridazyl complexes of rhenium were synthesized in three steps beginning from fulvenes 1,2-CsH3(COHR)(COR). On-Metal synthesis and characterization of (Re(CO)3 {1,2- CSH3(CRN)(CRN)}] (R=C6RtOMe, C6RtCI, C4H30) and some off-metal pyridazines ...


High Pressure Liquid Chromatography Studies Of The Reaction Of Platinum Complexes With Peptides, Khaja Muneeruddin 2010 Western Kentucky University

High Pressure Liquid Chromatography Studies Of The Reaction Of Platinum Complexes With Peptides, Khaja Muneeruddin

Masters Theses & Specialist Projects

Platinum complexes (cisplatin, carboplatin and oxaliplatin) are effective anticancer agents. However the major drawbacks of platinum chemotherapy are toxic side effects and resistance. The affinity of platinum complexes to sulfur donor ligands of side chains of methionine and cysteine amino acids was assumed to be responsible for toxicity and resistance. Recently, it was found that the reaction of platinum complex with proteins containing sulfur donor ligands could actually favor its anticancer activity. Copper transporter 1 (Ctr 1), a protein involved in the transport of copper into the cell, also helps in the influx of cisplatin by binding to N-terminal domain ...


Thoracic Target Volume Delineation Using Various Maximum-Intensity Projection Computed Tomography Image Sets For Stereotactic Body Radiation Therapy, David A. Zamora 2010 University of Texas Graduate School of Biomedical Sciences at Houston

Thoracic Target Volume Delineation Using Various Maximum-Intensity Projection Computed Tomography Image Sets For Stereotactic Body Radiation Therapy, David A. Zamora

UT GSBS Dissertations and Theses (Open Access)

The motion of lung tumors during respiration makes the accurate delivery of radiation therapy to the thorax difficult because it increases the uncertainty of target position. The adoption of four-dimensional computed tomography (4D-CT) has allowed us to determine how a tumor moves with respiration for each individual patient. Using information acquired during a 4D-CT scan, we can define the target, visualize motion, and calculate dose during the planning phase of the radiotherapy process. One image data set that can be created from the 4D-CT acquisition is the maximum-intensity projection (MIP). The MIP can be used as a starting point to ...


Photomediated Synthesis Of Silver Triangular Bipyramids And Prisms: The Effect Of Ph And Bspp, Jian Zhang, Mark R. Langille, Chad A. Mirkin 2010 University of Nebraska-Lincoln

Photomediated Synthesis Of Silver Triangular Bipyramids And Prisms: The Effect Of Ph And Bspp, Jian Zhang, Mark R. Langille, Chad A. Mirkin

Faculty Publications -- Chemistry Department

The photomediated synthesis of silver right triangular bipyramids and prisms has been studied, and we have determined that pH and [BSPP]/[Ag+] ratio (bis(p-sulfonatophenyl)phenylphosphine, BSPP) finely control the reaction rate and, consequently, the crystal growth pathway and morphology of final products. A fast reaction rate, realized at a high pH such as 10 or 11 and a [BSPP]/[Ag+] ratio close to 1.0, is necessary to synthesize (100)-faceted right triangular bipyramids in high yield by preferential deposition on (111) facets of planar-twinned seeds. A slower reaction rate, which occurs at lower pH or higher [BSPP ...


A Computational Framework To Support The Automated Analysis Of Routine Electroencephalographic Data, William Pressly, jr. 2010 Clemson University

A Computational Framework To Support The Automated Analysis Of Routine Electroencephalographic Data, William Pressly, Jr.

All Dissertations

Epilepsy is a condition in which a patient has multiple unprovoked seizures which are not precipitated by another medical condition. It is a common neurological disorder that afflicts 1% of the population of the US, and is sometimes hard to diagnose if seizures are infrequent. Routine Electroencephalography (rEEG), where the electrical potentials of the brain are recorded on the scalp of a patient, is one of the main tools for diagnosing because rEEG can reveal indicators of epilepsy when patients are in a non-seizure state. Interpretation of rEEG is difficult and studies have shown that 20-30% of patients at specialized ...


Synthesis, Kinetic And Photocatalytic Studies Of Porphyrin-Ruthenium-Oxo Complexes, Yan Huang 2010 Western Kentucky University

Synthesis, Kinetic And Photocatalytic Studies Of Porphyrin-Ruthenium-Oxo Complexes, Yan Huang

Masters Theses & Specialist Projects

Macrocyclic ligand-complexed transition metal-oxo intermediates are the active oxidizing species in a variety of important biological and catalytic oxidation reactions. Many transition metal catalysts have been designed to mimic the predominant oxidation catalysts in Nature, namely the cytochrome P450 enzymes. Ruthenium porphyrin complexes have been the center of the research and have successfully been utilized, as catalysts, in major oxidation reactions such as the hydroxylation of alkanes. This study focuses on kinetic and photocatalytic studies of oxidation reactions with wellcharacterized high-valent ruthenium-oxo porphyrin complexes.
The trans-dioxoruthenium(VI) porphyrins have been among the best characterized metal-oxo intermediates and their involvement ...


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