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A Study Of The Growth And Structure Of Chromium And Iron Oxide Films On Pd(001) Using X-Ray Photoelectron Diffraction And Low Energy Electron Diffraction, Tina Dhekial-Phukan 2010 Missouri University of Science and Technology

A Study Of The Growth And Structure Of Chromium And Iron Oxide Films On Pd(001) Using X-Ray Photoelectron Diffraction And Low Energy Electron Diffraction, Tina Dhekial-Phukan

Doctoral Dissertations

"In this study, attempts were made to grow well-ordered chromium- and iron-oxide films on a Pd(001) surface, and two sample preparation techniques, the multilayer and the sequential growth techniques, were used to grow these transition metal oxide films. The study is a part of a larger project that aims to look into the interaction between metal substrates and the overlayers grown on them. Previous studies of oxide films on Ag(001) resulted in the growth of 4-fold and 3-fold symmetry oxide structures from the multilayer and sequential growth techniques respectively. The present investigation's goal was to study how the growth of …


Adsorption And Segmental Dynamics Of Acrylate And Methacrylate Polymers Adsorbed On A Silica Surface, Piyawan Krisanangkura 2010 Missouri University of Science and Technology

Adsorption And Segmental Dynamics Of Acrylate And Methacrylate Polymers Adsorbed On A Silica Surface, Piyawan Krisanangkura

Doctoral Dissertations

"Poly(isopropyl acrylate)-d₇ (PIPA- d₇) was studied using ²H solid-state NMR and modulated differential scanning calorimetry (MDSC). The polymer was deuterated on the methyl groups and side-chain methine. The PIPA- d₇ was adsorbed onto Cab-O-Sil silica. These two types of deuterons each showed their own characteristic deuterium nuclear magnetic resonance (NMR) spectra for bulk PIPA- d₇. The ²H NMR spectra of adsorbed PIPA- d₇ samples showed the presence of heterogeneity of the segmental dynamics. A residual powder pattern was found in the spectra of the surface samples at higher temperatures, indicating that the segments were tightly attached to the silica. The …


Ground Penetrating Radar Investigations In Upper Kama Potash Mines, Oleg N. Kovin 2010 Missouri University of Science and Technology

Ground Penetrating Radar Investigations In Upper Kama Potash Mines, Oleg N. Kovin

Doctoral Dissertations

"An understanding of the structure and state of the rock mass surrounding underground openings in the potash mines is critically important for safe mining, planning the methods of extraction of an orebody, and preventing the influx of ground water. Continuous common offset ground penetrating radar (GPR) data were acquired in the potash mine operated by the Joint Stock Company (JSC) "Silvinit" (Russia) as part of an investigation of both pre-existing fractures exposed by mine workings and other anomalous geological structures. During the course of GPR investigation, the electrical properties of salt-bearing units were determined, site-specific data acquisition techniques and object-oriented …


Three-Body Dynamics In Single Ionization Of Atomic Hydrogen By 75 Kev Proton Impact, Aaron C. LaForge 2010 Missouri University of Science and Technology

Three-Body Dynamics In Single Ionization Of Atomic Hydrogen By 75 Kev Proton Impact, Aaron C. Laforge

Doctoral Dissertations

"Doubly differential cross sections (DDCS) for single ionization of atomic hydrogen by 75 keV proton impact have been measured as a function of the projectile scattering angle and energy loss. This pure three-body collision system represents a fundamental test case for the study of the reaction dynamics in few-body systems. A comparison between theory and experiment reveals that three-body dynamics is important at all scattering angles, and that an accurate description of the role of the projectile-target nucleus interaction as well as the second order projectile-electron interaction remains a major challenge to theory. However, progress is being made in understanding …


Analysis And Occurrence Of Disinfection By-Products In Fresh And Salt Water, Honglan Shi 2010 Missouri University of Science and Technology

Analysis And Occurrence Of Disinfection By-Products In Fresh And Salt Water, Honglan Shi

Doctoral Dissertations

"Haloacetic acids, trihalomethanes, and bromate are important toxic water disinfection by-products (DBPs) that the US Environmental Protection Agency (USEPA) regulates in drinking water. Iodoacetic acids and halonitromethanes (HNMs) are the unregulated emerging DBPs that have been recently found in the disinfected drinking waters, and which have much higher toxicity than the regulated DBPs. The purpose of this study was to develop new analytical methods for analysis of these emerging DBPs, to study their occurrence in Missouri drinking water systems, and to investigate the occurrence and formation of these DBPs in saltwater and seawater based marine park aquaria. A new rapid …


Dynamic Ant Colony Optimization For Globally Optimizing Consumer Preferences, Pavitra Dhruvanarayana 2010 Missouri University of Science and Technology

Dynamic Ant Colony Optimization For Globally Optimizing Consumer Preferences, Pavitra Dhruvanarayana

Masters Theses

"Consumer preference for any product or product feature can be expressed in the form of a utility function. Many such utility functions form a part of a preference map, where each of these are expressed in terms of the attributes defining the product or the product feature. In order to optimize the design, it is required to optimize the overall utility function obtained by a mathematical combination of individual utility functions defined in the preference map. The objective of this research is to devise and implement an algorithm to optimize all the individual utility functions comprised in a preference map …


Determination Of Total Dissolved Cobalt In Uv-Irradiated Seawater Using Flow Injection With Chemiluminescence Detection, Rachel U. Shelley, Bernhard Zachhuber, Peter N. Sedwick, Paul J. Worsfold, Maeve C. Lohan 2010 Old Dominion University

Determination Of Total Dissolved Cobalt In Uv-Irradiated Seawater Using Flow Injection With Chemiluminescence Detection, Rachel U. Shelley, Bernhard Zachhuber, Peter N. Sedwick, Paul J. Worsfold, Maeve C. Lohan

OES Faculty Publications

A sensitive flow-injection method with chemiluminescence detection (FI-CL) for the determination of dissolved cobalt in open ocean samples, suitable for shipboard use has been developed. To date, FI methods for dissolved cobalt have been used only in coastal and estuarine waters. Therefore, significant modifications to existing methods were required, including (1) the use of a commercially available iminodiacetate (IDA) resin (Toyopearl AF-chelate 650M) in place of resin immobilized 8-hydroxyquinoline for online preconcentration and matrix removal, (2) the introduction of acidified ammonium acetate (pH 4) as a column-conditioning step before sample loading and rinse steps, and most importantly, (3) UV irradiation …


On The Fractional Solubillity Of Copper In Marine Aerosols: Toxicity Of Aeolian Copper Revisited, Edward R. Sholkovitz, Peter N. Sedwick, Thomas M. Church 2010 Old Dominion University

On The Fractional Solubillity Of Copper In Marine Aerosols: Toxicity Of Aeolian Copper Revisited, Edward R. Sholkovitz, Peter N. Sedwick, Thomas M. Church

OES Faculty Publications

Paytan et al. (2009) argue that the atmospheric deposition of aerosols lead to copper concentrations that are potentially toxic to marine phytoplankton in a large area of tropical and subtropical North Atlantic Ocean. A key assumption in their model is that all marine aerosols (mineral dust and anthropogenic particles) have a high (40%) fractional solubility of copper. Our data show that the fractional solubility of copper for Saharan dust over the Sargasso Sea and Bermuda is significantly lower (1-7%). In contrast, anthropogenic aerosols with non-Saharan sources have significantly higher values (10-100%). Hence, the potential Cu toxicity in the tropical and …


The Widespread Occurrence Of Coupled Carbonate Dissolution/Reprecipitation In Surface Sediments On The Bahamas Bank, David J. Burdige, Xinping Hu, Richard C. Zimmerman 2010 Old Dominion University

The Widespread Occurrence Of Coupled Carbonate Dissolution/Reprecipitation In Surface Sediments On The Bahamas Bank, David J. Burdige, Xinping Hu, Richard C. Zimmerman

OES Faculty Publications

Using two complimentary approaches (pore water advection/diffusion/reaction modeling and stable isotope mass balance calculations) we show that carbonate dissolution/reprecipitation occurs on early diagenetic time scales across a broad range of sediments on the Great Bahamas Bank. The input of oxygen into the sediments, which strongly controls sediment carbonate dissolution, has two major sources belowground input by seagrasses (that is, seagrass O2 pumping), and permeability-driven advective pore water exchange. The relative importance of these O2 delivery mechanisms depends on both seagrass density, and on how bottom water flow interacts with the seagrass canopy and leads to this advective exchange. …


Causes Of Tropical Atlantic Paleo-Salinity Variation During Periods Of Reduced Amoc, Xiuquan Wan, Ping Chang, Matthew W. Schmidt 2010 Old Dominion University

Causes Of Tropical Atlantic Paleo-Salinity Variation During Periods Of Reduced Amoc, Xiuquan Wan, Ping Chang, Matthew W. Schmidt

OES Faculty Publications

During periods of reduced Atlantic meridional overturning circulation (AMOC) associated with a freshening of northern North Atlantic surface water, paleo proxy records indicate a corresponding surface salinity increase over the entire tropical Atlantic. Although latitudinal-shifts in the mean position of the Atlantic Intertropical Convergence Zone (ITCZ) can explain certain features of the paleo salinity reconstructions, this mechanism does not offer an explanation for the reconstructed basin-wide paleo-salinity response to AMOC change. Here, we present new results from general circulation model simulations that suggest the sea surface salinity (SSS) increase in the tropical north Atlantic during periods of weakened AMOC is …


Potential Climate-Change Impacts On The Chesapeake Bay, Raymond G. Najjar, Christopher R. Pyke, Mary Beth Adams, Denise Breitburg, Carl Hershner, et al 2010 Virginia Institute of Marine Science

Potential Climate-Change Impacts On The Chesapeake Bay, Raymond G. Najjar, Christopher R. Pyke, Mary Beth Adams, Denise Breitburg, Carl Hershner, Et Al

VIMS Articles

We review current understanding of the potential impact of climate change on the Chesapeake Bay. Scenarios for CO2 emissions indicate that by the end of the 21st century the Bay region will experience significant changes in climate forcings with respect to historical conditions, including increases in CO2 concentrations, sea level, and water temperature of 50–160%, 0.7–1.6m, and 2–6C, respectively. Also likely are increases in precipitation amount (very likely in the winter and spring), precipitation intensity, intensity of tropical and extratropical cyclones (though their frequency may decrease), and sea-level variability. The greatest uncertainty is associatedwith changes in annual streamflow, though it …


Extraction Experiments Using Commerciallv Available Spices, Armando M. Guidote Jr, Maricar O. Ribo-Ramos, Dante Gilbert L. de Leon 2010 Ateneo de Manila University

Extraction Experiments Using Commerciallv Available Spices, Armando M. Guidote Jr, Maricar O. Ribo-Ramos, Dante Gilbert L. De Leon

Chemistry Faculty Publications

Safe and cost-effective experiments were designed for high school students to enhance their laboratory skills and knowledge on polarity and separation of mixtures. Annatto, Spanish paprika and turmeric were extracted yielding red-orange, light red-orange and yellow color, respectively. These were combined with a blue aqueous solution made from food color resulting to green mixtures. These were all extracted with kerosene or oil/kerosene. The non-polar solutes for each mixture combined with the kerosene or oil/kerosene layer, making the polar phase blue again. Students gained a better understanding of the concepts as shown in their laboratory report and test results.


Personal Exposure Of Children To Formaldehyde In Perth, Western Australia, Victoria S. Lazenby 2010 Edith Cowan University

Personal Exposure Of Children To Formaldehyde In Perth, Western Australia, Victoria S. Lazenby

Theses: Doctorates and Masters

Formaldehyde is a common air pollutant that tends to be found in elevated concentrations in indoor air. Exposure to formaldehyde has the potential to impact on respiratory health, particularly amongst sensitive individuals and populations, including children. Children spend most of their time indoors at home, however, there are very little data on the contribution of formaldehyde concentrations in homes to personal exposure in children. The principal aim of this cross sectional study was to investigate whether the domestic environment is the most significant source of personal exposure of formaldehyde in children. Forty-one primary school children (aged between 8 and 12) …


Evaluation Of The Potential Of Raman Microspectroscopy For Prediction Of Chemotherapeutic Response To Cisplatin In Lung Adenocarcinoma, Haq Nawaz, Franck Bonnier, Peter Knief, Orla Howe, Fiona Lyng, Aidan Meade, Hugh Byrne 2010 Technological University Dublin

Evaluation Of The Potential Of Raman Microspectroscopy For Prediction Of Chemotherapeutic Response To Cisplatin In Lung Adenocarcinoma, Haq Nawaz, Franck Bonnier, Peter Knief, Orla Howe, Fiona Lyng, Aidan Meade, Hugh Byrne

Articles

The study of the interaction of anticancer drugs with mammalian cells in vitro is important to elucidate the mechanisms of action of the drug on its biological targets. In this context, Raman spectroscopy is a potential candidate for high throughput, noninvasive analysis. To explore this potential, the interaction of cis-Diamminedichloroplatinum (II) (Cisplatin) with a human lung adenocarcinoma cell line (A549) was investigated using Raman microspectroscopy. The results were correlated with parallel measurements from the MTT cytotoxicity assay, which yielded an IC50 value of 1.2±0.2 μM. To further confirm the spectral results, Raman spectra were also acquired from DNA extracted from …


Studies Of Chemical Fixation Effects In Human Cell Lines Using Raman Microspectroscopy, Aidan Meade, Colin Clarke, Florence Draux, Ganesh Sockalingum, Michel Manfait, Fiona Lyng, Hugh Byrne 2010 Technological University Dublin

Studies Of Chemical Fixation Effects In Human Cell Lines Using Raman Microspectroscopy, Aidan Meade, Colin Clarke, Florence Draux, Ganesh Sockalingum, Michel Manfait, Fiona Lyng, Hugh Byrne

Articles

The in vitro study of cellular species using Raman spectroscopy has proven a powerful non-invasive modality for the analysis of cell constituents and processes. This work uses micro-Raman spectroscopy to study the chemical fixation mechanism in three human cell lines (normal skin, normal bronchial epithelium, and lung adenocarcinoma) employing fixatives that preferentially preserve proteins (formalin), and nucleic acids (Carnoy’s fixative and methanol–acetic acid). Spectral differences between the mean live cell spectra and fixed cell spectra together with principal components analysis (PCA), and clustering techniques were used to analyse and interpret the spectral changes. The results indicate that fixation in formalin …


Investigation Of The Influence Of High Risk Human Papillomavirus On The Biochemical Composition Of Cervical Cancer Cells Using Vibrational Spectroscopy, Kamila Ostrowska, Alison Malkin, Aidan Meade, John O'Leary, Cara Martin, Cathy Spillane, Hugh Byrne, Fiona Lyng 2010 Technological University Dublin

Investigation Of The Influence Of High Risk Human Papillomavirus On The Biochemical Composition Of Cervical Cancer Cells Using Vibrational Spectroscopy, Kamila Ostrowska, Alison Malkin, Aidan Meade, John O'Leary, Cara Martin, Cathy Spillane, Hugh Byrne, Fiona Lyng

Articles

The main aetiology of cervical cancer is infection with high risk human papillomavirus (HPV). Cervical cancer is almost 100% curable if detected in the early stages. Thus, information about the presence and levels of HPV in patient samples has high clinical value. As current screening methods, such as the Pap smear test, are highly subjective and in many cases show low sensitivity and specificity, new supportive techniques are desirable to improve the quality of cervical cancer screening. In this study, vibrational spectroscopic techniques (Raman and Fourier Transform Infra Red absorption) have been applied to the investigation of four cervical cancer …


Spectroscopic And Chemometric Approaches To Radiobiological Analyses, Aidan Meade, Hugh Byrne, Fiona Lyng 2010 Technological University Dublin

Spectroscopic And Chemometric Approaches To Radiobiological Analyses, Aidan Meade, Hugh Byrne, Fiona Lyng

Articles

No abstract provided.


Functional And Pathological Analysis Of Biological Systems Using Vibrational Spectroscopy With Chemometric And Heuristic Approaches, Aidan Meade, Colin Clarke, Franck Bonnier, Kelvin W. Poon, Amaya Garcia, Peter Knief, Kamila Ostrowska, Lorenzo Salford, Haq Nawaz, Fiona Lyng, Hugh Byrne 2010 Technological University Dublin

Functional And Pathological Analysis Of Biological Systems Using Vibrational Spectroscopy With Chemometric And Heuristic Approaches, Aidan Meade, Colin Clarke, Franck Bonnier, Kelvin W. Poon, Amaya Garcia, Peter Knief, Kamila Ostrowska, Lorenzo Salford, Haq Nawaz, Fiona Lyng, Hugh Byrne

Articles

Vibrational spectroscopy (Raman and FTIR microspectroscopy) is an attractive modality for the analysis of biological samples since it provides a complete non-invasive acquisition of the biochemical fingerprint of the sample. Studies in our laboratory have applied vibrational spectroscopy to the analysis of biological function in response to external agents (chemotherapeutic drugs, ionising radiation, nanoparticles), together with studies of the pathology of tissue (skin and cervix) in health and disease. Genetic algorithms have been used to optimize spectral treatments in tandem with the analysis of the data (using generalized regression neural networks (GRNN), artificial neural networks (ANN), partial least squares modelling …


Imaging Live Cells Grown On A Three Dimensional Collagen Matrix Using Raman Microspectroscopy, Franck Bonnier, Peter Knief, Basil Lim, Aidan Meade, Jennifer Dorney, Kunal Bhattacharya, Fiona Lyng, Hugh Byrne 2010 Technological University Dublin

Imaging Live Cells Grown On A Three Dimensional Collagen Matrix Using Raman Microspectroscopy, Franck Bonnier, Peter Knief, Basil Lim, Aidan Meade, Jennifer Dorney, Kunal Bhattacharya, Fiona Lyng, Hugh Byrne

Articles

Three dimensional collagen gels have been used as matrices for the imaging of live cells by Raman spectroscopy. The study is conducted on a human lung adenocarcinoma (A549) and a spontaneously immortalized human epithelial keratinocyte (HaCaT) cell line. The lateral resolution of the system has been estimated to be


Corrosion Protection Of Aa 2024-T3 Aluminium Alloys Using 3, 4-Diaminobenzoic Acid Chelated Zirconium-Silane Hybrid Sol-Gels, P.C. Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette McDonagh, Brendan Duffy 2010 Technological University Dublin

Corrosion Protection Of Aa 2024-T3 Aluminium Alloys Using 3, 4-Diaminobenzoic Acid Chelated Zirconium-Silane Hybrid Sol-Gels, P.C. Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, Brendan Duffy

Articles

Organic-inorganic polymers formed by hydrolysis/condensation reactions of alkoxide precursors, such as organically modified silanes (Ormosils) have found applications as electronic, optical and protective coatings. Such coatings possess important characteristics such as chemical stability, physical strength and scratch resistance. Further performance improvement is achieved through the incorporation of zirconium and titanium based nanoparticles, also formed through the sol-gel process. However due to the inherent difference in the reactivity of the precursors, the hydrolysis of each precursor must be carried out separately before being combined for final condensation. Zirconium precursors are commonly chelated using acetic acid or acetyl acetonate prior to hydrolysis, …


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