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2011

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Articles 301 - 330 of 7765

Full-Text Articles in Physical Sciences and Mathematics

Interacting Stochastic Processes: From Viciousness To Caging To Force Chains, Shiliyang Xu Dec 2011

Interacting Stochastic Processes: From Viciousness To Caging To Force Chains, Shiliyang Xu

Physics - Dissertations

This thesis documents a quest to develop and study several novel interacting stochastic processes. As for the first example, we generalize a system of vicious random walkers in which the only interaction between any two random walkers is that when they intersect, both walkers are annihilated. We define a system of N vicious accelerating walkers with each walker undergoing random acceleration and compute the survival probability distribution for this system. We also define and study a system of N vicious Levy flights in which any two Levy flights crossing one another annihilate each other. The average mean-squared displacement of a …


Design And Implementation Of An Open Framework For Ubiquitous Carbon Footprint Calculator Applications, Farzana Rahman, Casey O'Brien, Sheikh Iqbal Ahamed, He Zhang, Lin Liu Dec 2011

Design And Implementation Of An Open Framework For Ubiquitous Carbon Footprint Calculator Applications, Farzana Rahman, Casey O'Brien, Sheikh Iqbal Ahamed, He Zhang, Lin Liu

Mathematics, Statistics and Computer Science Faculty Research and Publications

As climate change is becoming an important global issue, more and more people are beginning to pay attention to reducing greenhouse gas emissions. To measure personal or household carbon dioxide emission, there are already plenty of carbon footprint calculators available on the web. Most of these calculators use quantitative models to estimate carbon emission caused by a user's activities. Although these calculators can promote public awareness regarding carbon emission due to an individual's behavior, there are concerns about the consistency and transparency of these existing CO2 calculators. Apart from a small group of smart phone based carbon footprint calculator …


Relating Land Cover And Channel Morphology To Stream Flow Function In The Lower Pee Dee Watershed, South Carolina, Zachary Smoot Dec 2011

Relating Land Cover And Channel Morphology To Stream Flow Function In The Lower Pee Dee Watershed, South Carolina, Zachary Smoot

All Theses

The South Carolina Pee Dee Project (SCPDP) aims to develop a method for the determination of Minimum Allowable Flows (MAFs) in streams in the Pee Dee region. This study is a portion of the larger SCPDP, focusing primarily upon analyses of geomorphic and hydrologic processes, as well as landscape and habitat analyses. Specific objectives include: 1) To distinguish the effect of various land cover classes and scales of analyses on components of stream flow function; 2) To determine trends in hydraulic geometry (regional curves) for the SCPDP region; and 3) To determine what measures of stream flow function, stream geomorphology, …


Data-Intensive Computing For Bioinformatics Using Virtualization Technologies And Hpc Infrastructures, Pengfei Xuan Dec 2011

Data-Intensive Computing For Bioinformatics Using Virtualization Technologies And Hpc Infrastructures, Pengfei Xuan

All Theses

The bioinformatics applications often involve many computational components and massive data sets, which are very difficult to be deployed on a single computing machine. In this thesis, we designed a data-intensive computing platform for bioinformatics applications using virtualization technologies and high performance computing (HPC) infrastructures with the concept of multi-tier architecture, which can seamlessly integrate the web user interface (presentation tier), scientific workflow (logic tier) and computing infrastructure (data/computing tier). We demonstrated our platform on two bioinformatics projects. First, we redesigned and deployed the cotton marker database (CMD) (http://www.cottonmarker.org), a centralized web portal in the cotton research community, using the …


A Gravitational Wave Observatory Operating Beyond The Quantum Shot-Noise Limit: Squeezed Light In Application, J. Abadie, B. P. Abbott, T. D. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Volker Quetschke, Joseph D. Romano Dec 2011

A Gravitational Wave Observatory Operating Beyond The Quantum Shot-Noise Limit: Squeezed Light In Application, J. Abadie, B. P. Abbott, T. D. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Volker Quetschke, Joseph D. Romano

Physics & Astronomy Faculty Publications

Around the globe several observatories are seeking the first direct detection of gravitational waves (GWs). These waves are predicted by Einstein's general theory of relativity(1) and are generated, for example, by black-hole binary systems(2). Present GW detectors are Michelson-type kilometre-scale laser interferometers measuring the distance changes between mirrors suspended in vacuum. The sensitivity of these detectors at frequencies above several hundred hertz is limited by the vacuum (zero-point) fluctuations of the electromagnetic field. A quantum technology-the injection of squeezed light(3)-offers a solution to this problem. Here we demonstrate the squeezed-light enhancement of GEO 600, which will be the GW observatory …


Rigging And Texturing Considerations For The Short Film Spider Fight, Casey Johnson Dec 2011

Rigging And Texturing Considerations For The Short Film Spider Fight, Casey Johnson

All Theses

This paper delves into two separate production areas of the short film, Spider Fight: the approach used to solve the problem of rigging eyelids for 3d characters, and the pipelines that were implemented for texturing 3d assets. Typically, problems exist in the rigging of eyelids for 3d characters. Productions rely on a series of blend shapes, or a combination of joints and blend shapes, to produce satisfactory eyelid movement. Spider Fight, however, used a series of curves and joints to control the movement of the eyelids, which allowed a high degree of control over eyelid movement, and also fast editing …


Investigation Of A Novel Method For Polonium-210 Determination In Groundwater, Tara Matheny Dec 2011

Investigation Of A Novel Method For Polonium-210 Determination In Groundwater, Tara Matheny

All Theses

A novel method was investigated for the quantification of 210Po in water as an alternative to the standard method of spontaneous plating onto Ag disks followed by quantification with an alpha spectrometer. The novel method concentrated a 0.5L sample by MnO2 co-precipitation followed by dissolution of the precipitate into a solution. Polonium-210 was separated from the solution and quantified in a column containing a 50:50 by volume mixture of Pb resin (Eichrom Technologies, Inc.) mixed with granulated CaF2:Eu scintillator. The column containing 210Po is quantified on a liquid scintillation counter without the introduction of liquid cocktail. The minimum detectable concentration …


Age, Stratigraphy And Depositional Environment Of The Pliocene Copper Canyon Formation, Death Valley, California, Torrey Nyborg Dec 2011

Age, Stratigraphy And Depositional Environment Of The Pliocene Copper Canyon Formation, Death Valley, California, Torrey Nyborg

Loma Linda University Electronic Theses, Dissertations & Projects

The Copper Canyon Formation, a fluvial-lacustrine deposit exposed within the Black Mountains of Death Valley National Park, has only previously been broadly included in regional tectonic and depositional analyses. The formation is significant because it preserves numerous shoreline-playa features including highly abundant and diverse mammal and bird tracks. The formation represents a basin fill sequence consisting of approximately 1800 m of conglomerates, basalt flows, and lacustrine deposits. A measured type section along with x-ray diffraction, isotopic analysis, and thin section petrography shows an evolution of the ancient Copper Canyon lake from an hypersaline evaporative lake to a perennial saline lake …


Ensemble Methods For Dynamic Data Assimilation Of Chemical Observations In Atmospheric Models, Adrian Sandu, Emil Constantinescu, Gregory R. Carmichael, Tianfeng Chai, Dacian Daescu, John H. Seinfeld Dec 2011

Ensemble Methods For Dynamic Data Assimilation Of Chemical Observations In Atmospheric Models, Adrian Sandu, Emil Constantinescu, Gregory R. Carmichael, Tianfeng Chai, Dacian Daescu, John H. Seinfeld

Mathematics and Statistics Faculty Publications and Presentations

The task of providing an optimal analysis of the state of the atmosphere requires the development of dynamic data-driven systems (DDDAS) that efficiently integrate the observational data and the models. Data assimilation, the dynamic incorporation of additional data into an executing application, is an essential DDDAS concept with wide applicability. In this paper we discuss practical aspects of nonlinear ensemble Kalman data assimilation applied to atmospheric chemical transport models. We highlight the challenges encountered in this approach such as filter divergence and spurious corrections, and propose solutions to overcome them, such as background covariance inflation and filter localization. The predictability …


Reliable A-Posteriori Error Estimators For Hp-Adaptive Finite Element Approximations Of Eigenvalue/Leigenvector Problems, Stefano Giani, Luka Grubisic, Jeffrey S. Ovall Dec 2011

Reliable A-Posteriori Error Estimators For Hp-Adaptive Finite Element Approximations Of Eigenvalue/Leigenvector Problems, Stefano Giani, Luka Grubisic, Jeffrey S. Ovall

Mathematics and Statistics Faculty Publications and Presentations

We present reliable a-posteriori error estimates for hp-adaptive finite element approxima- tions of eigenvalue/eigenvector problems. Starting from our earlier work on h adaptive finite element approximations we show a way to obtain reliable and efficient a-posteriori estimates in the hp-setting. At the core of our analysis is the reduction of the problem on the analysis of the associated boundary value problem. We start from the analysis of Wohlmuth and Melenk and combine this with our a-posteriori estimation framework to obtain eigenvalue/eigenvector approximation bounds.


Method Development And Validation Of The Quantitation Of 19 Antipsychotics Using Deuterated Internal Standards, Anthony S. Epps Dec 2011

Method Development And Validation Of The Quantitation Of 19 Antipsychotics Using Deuterated Internal Standards, Anthony S. Epps

Chemistry Theses

Antipsychotic drugs or neuroleptics are used primarily for psychiatric disorders such as schizophrenia, psychosis, and bipolar disorder. In forensic science antipsychotics are drugs of considerable interest because of their potential abuse, involvement in suicides, and they are frequently associated with sudden death investigations. Well-characterized and fully validated analytical data is necessary to generate reproducible and reliable results. As a result, data can be correctly interpreted and objectively demonstrate in its applicability for the intended use. This research has developed and validated a method that is selective, sensitive and accurate using liquid chromatography–tandem mass spectrometry (LC–MS/MS) for the simultaneous determination of …


Analyzing Spring Freeze Impacts On Deciduous Forest Productivity Using Modis Satellite Imagery, Karl Lintvedt Dec 2011

Analyzing Spring Freeze Impacts On Deciduous Forest Productivity Using Modis Satellite Imagery, Karl Lintvedt

Graduate Theses and Dissertations

The impacts of an April 2007 spring freeze event on the productivity of deciduous broadleaf forest were analyzed using geographic information system (GIS) tools. Forest productivity was modeled using the Enhanced Vegetation Index (EVI), as recorded by the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite sensor. Measures of spatial autocorrelation were used to quantify the degree of spatial congruence between a map depicting the severity of the freeze event, and maps modeling forest productivity throughout the year. The results show a geographic correlation between the unseasonably low minimum temperatures sustained during the freeze and the unusually low forest productivity that followed. …


Studies Toward The Development Of A Microelectrode Array For Detection Of Dopamine Through Redox Cycling, Anupama Aggarwal Dec 2011

Studies Toward The Development Of A Microelectrode Array For Detection Of Dopamine Through Redox Cycling, Anupama Aggarwal

Graduate Theses and Dissertations

Redox cycling is an electrochemical technique that cycles the reversible redox species between its oxidative states repeatedly on generator and collector electrodes. Two or more individually-addressable microelectrodes located close to each other allow redox cycling to be possible. Electrochemical behavior of a biologically important molecule, dopamine is examined under redox cycling conditions. To our knowledge, this is the first report on detection of physiological concentration of dopamine in presence of up to 100 times excess ascorbate with the use of redox cycling, without the involvement of polymer coating such as Nafion®.

Microfabrication was used to produce different geometries (parallel bands …


Water Quality Trends For Section 319 Priority Watersheds In Northwest Arkansas, 1997-2010, Bryan William Bailey Dec 2011

Water Quality Trends For Section 319 Priority Watersheds In Northwest Arkansas, 1997-2010, Bryan William Bailey

Graduate Theses and Dissertations

Northwest Arkansas contains two Section 319 Priority Watersheds that the Arkansas Natural Resources Commission (ANRC) has identified as being impacted by point and nonpoint sources of pollution (i.e., phosphorus, nitrogen, and sediment), and the Arkansas Water Resources Center (AWRC) has monitored the water quality at several sites within these watersheds. Water-quality data has been collected over the last decade within the Illinois River Watershed (HUC #11110103) and the Upper White River Basin (Beaver Reservoir HUC# 11010001), each watershed containing three sampling sites. The Illinois River Watershed sites are located on the Illinois River, Osage Creek, and Ballard Creek, and the …


Dynamics And Catalytic Resolution Of Selected Chiral Organolithiums, Timothy Kum Beng Dec 2011

Dynamics And Catalytic Resolution Of Selected Chiral Organolithiums, Timothy Kum Beng

Graduate Theses and Dissertations

One of the most important developments of the last decade has been the emergence of new methods to dynamically resolve racemic organolithiums using stoichiometric amounts of the chiral ligand. When this concept is implemented successfully, it obviates the need for covalently attached chiral auxiliary based methods, asymmetric deprotonation, and asymmetric synthesis of a precursor stannane as ways to access enantioenriched organolithium compounds for use in asymmetric synthesis. Since certain electrophiles consume the chiral ligand, it is desirable to render this process catalytic in the chiral ligand.

As part of a larger study on the amenability of chiral organolithiums to a …


Environmental Influences On Juvenile Fish Abundances In A River-Dominated Coastal System, Laure Carassou, Brian Dzwonkowski, Frank J. Hernandez, Jr., Sean P. Powers, William M. Graham, Kyeong Park, John Mareska Dec 2011

Environmental Influences On Juvenile Fish Abundances In A River-Dominated Coastal System, Laure Carassou, Brian Dzwonkowski, Frank J. Hernandez, Jr., Sean P. Powers, William M. Graham, Kyeong Park, John Mareska

University Faculty and Staff Publications

We investigated the influence of climatic and environmental factors on variations in juvenile abundances of marine fishes in a river-dominated coastal system of the north-central Gulf of Mexico, where an elevated primary productivity sustains fisheries of high economic importance. Fish were collected monthly with an otter trawl at three stations near Mobile Bay from 1982 to 2007. Fish sizes were used to isolate juvenile stages within the data set, and monthly patterns in juvenile fish abundance and size were then used to identify seasonal peaks for each species. The average numbers of juvenile fish collected during these seasonal peaks in …


Multicomponent Reactions For The Preparation Of Fluorous Taged Pyrimidines And Thiopyrimidines And Their Derivatisation To Obtain Biaryl-Substituted Heterocycles, Bruno Piqani Dec 2011

Multicomponent Reactions For The Preparation Of Fluorous Taged Pyrimidines And Thiopyrimidines And Their Derivatisation To Obtain Biaryl-Substituted Heterocycles, Bruno Piqani

Graduate Masters Theses

This thesis presents a work in the field of multicomponent reactions (MCRs), one-step condensation between a fluorous tagged aldehyde, β-keto ester and urea derivatives. This process in literature is known as "Biginelli Reaction". This dissertation describes a new Biginelli reaction element, using fluorous component as a limiting agent.

Chapter one is an introduction of MCRs. A brief historical review, key principles as well as applications in different fields such as academic research, synthetic organic chemistry, and medicinal applications are presented.

Chapter two discusses the general features of the Biginelli reaction, microwave, and fluorous chemistry with a distinctive look from the …


Prototype Automated Flow-Through Sensor For Measuring Waterborne Microbial Concentrations Using Bulk Fluorescence, Susan M. Savill Dec 2011

Prototype Automated Flow-Through Sensor For Measuring Waterborne Microbial Concentrations Using Bulk Fluorescence, Susan M. Savill

Graduate Masters Theses

Timely and inexpensive monitoring of microbial ecology in the world's water supplies is crucial to the study of environmental and human impact on water quality and the prevention of disease outbreaks. Current technology is lacking in its ability to accurately measure and predict the presence of possible disease pathogens in a timely and cost effective manner. This paper describes the construction and initial testing of an automated prototype water sensor intended to detect fluctuations in microbial density in real-time by using bulk fluorescence of SYBR Gold stained bacteria. The sensor is comprised of off-the-shelf hardware and an in-house designed and …


Graduate Scholar Profiles, The Mcnair Team Dec 2011

Graduate Scholar Profiles, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


Mentor Profile, The Mcnair Team Dec 2011

Mentor Profile, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


High-Resolution Study Of Layering Within The Percolation And Soaked Facies Of The Greenland Ice Sheet, Joel Brown, Joel T. Harper, W. Tad Pfeffer, Neil Humphrey, John H. Bradford Dec 2011

High-Resolution Study Of Layering Within The Percolation And Soaked Facies Of The Greenland Ice Sheet, Joel Brown, Joel T. Harper, W. Tad Pfeffer, Neil Humphrey, John H. Bradford

Geosciences Faculty Publications

Within the percolation and soaked facies of the Greenland ice sheet, the relationship between radar-derived internal reflection horizons and the layered structure of the firm column is unclear. We conducted two small-scale ground-penetrating radar (GPR) surveys in conjunction with 10 m firm cores that we colleced within the percolation and soaked facies of the Greenland ice sheet. The two surveys were separated by the distance of about 50 km and about 340 m of elevation leading to about 40 days of difference in the duration of average annual melt. At the higher site (about 1997 ma.s.l.), which receives less melt, …


Evaluation Of Deformable Image Registration For Improved 4d Ct-Derived Ventilation For Image Guided Radiotherapy, Richard Castillo Dec 2011

Evaluation Of Deformable Image Registration For Improved 4d Ct-Derived Ventilation For Image Guided Radiotherapy, Richard Castillo

Dissertations and Theses (Open Access)

Recent treatment planning studies have demonstrated the use of physiologic images in radiation therapy treatment planning to identify regions for functional avoidance. This image-guided radiotherapy (IGRT) strategy may reduce the injury and/or functional loss following thoracic radiotherapy. 4D computed tomography (CT), developed for radiotherapy treatment planning, is a relatively new imaging technique that allows the acquisition of a time-varying sequence of 3D CT images of the patient's lungs through the respiratory cycle. Guerrero et al. developed a method to calculate ventilation imaging from 4D CT, which is potentially better suited and more broadly available for IGRT than the current standard …


Comparing Cropping System Productivity Between Fixed Rotations And A Flexible Fallow System Using Modeling And Historical Weather Data In The Semi-Arid Central Great Plains, Juan Jose Miceli-Garcia Dec 2011

Comparing Cropping System Productivity Between Fixed Rotations And A Flexible Fallow System Using Modeling And Historical Weather Data In The Semi-Arid Central Great Plains, Juan Jose Miceli-Garcia

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

In the Central Great Plains, the predominant crop rotation is winter wheat (Triticum aestivum L.)-fallow. Producers are looking to add diversity and intensity to their cropping systems by adding summer crops, however, the elimination of summer fallow may increase crop production risk. The objective of this study was to use crop simulation modeling to compare the productivity of two fixed rotations [winter wheat-corn (Zea mays L.)-fallow and winter wheat-corn-spring triticale (X Triticosecale Wittmack)] with simulated flexible fallow rotations. The flexible fallow rotations made the decision to plant triticale or use summer fallow prior to winter wheat seeding based …


Atlantic Multidecadal Oscillation-Forced Regional Summertime Precipitation Variations In The Central United States, Michael C. Veres Dec 2011

Atlantic Multidecadal Oscillation-Forced Regional Summertime Precipitation Variations In The Central United States, Michael C. Veres

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The purpose of this research is to identify the regional mechanisms by which the Atlantic Multidecadal Oscillation (AMO) influences summer (June-August) precipitation in the central U.S. This was accomplished by running two different sets of simulations using the Weather Research and Forecasting (WRF) regional climate model, one forced by observations and the other forced only by variations in the AMO as obtained via a global climate model (GCM). The results reveal a complex set of mechanisms active in the lower and middle troposphere by which the AMO influences summer circulation and precipitation in the central U.S. During the cold phase …


Climatic Controls On The Summertime Energy Balance Of A Thermokarst Lake In Northern Alaska: Short-Term, Seasonal, And Interannual Variability, Brittany L. Potter Dec 2011

Climatic Controls On The Summertime Energy Balance Of A Thermokarst Lake In Northern Alaska: Short-Term, Seasonal, And Interannual Variability, Brittany L. Potter

School of Natural Resources: Dissertations, Theses, and Student Research

Shallow, thermokarst lakes that develop atop permafrost are a prominent landscape feature on the Arctic Coastal Plain (ACP) of northern Alaska. The ACP is vulnerable to ongoing climate change and landscape modification, as thousands of thaw lakes and ponds are impacted by changes in temperature, precipitation, thawing permafrost, and human activity. Although summer in the Arctic is short, incoming solar radiation and lake evaporation are relatively high, and both factors play a significant role in the landscape water balance. Furthermore, lake evaporation is anticipated to increase as the ice-free season lengthens and water temperatures become warmer. To improve our understanding …


Abiotic Stress Responses In Photosynthetic Organisms, Joseph Msanne Dec 2011

Abiotic Stress Responses In Photosynthetic Organisms, Joseph Msanne

School of Natural Resources: Dissertations, Theses, and Student Research

Cellular and molecular aspects of abiotic stress responses in Arabidopsis thaliana subjected to cold, drought, and high salinity and in two photosynthetic green alga, Chlamydomonas reinhardtii and Coccomyxa sp. C-169, subjected to nitrogen deprivation were investigated. Cold, drought, and high salinity can negatively affect plant growth and crop production. The first research aimed at determining the physiological functions of the stress-responsive Arabidopsis thaliana RD29A and RD29B genes. Cold, drought, and salt induced both genes; the promoter of RD29Awas found to be more responsive to drought and cold stresses, whereas the promoter of RD29B was highly responsive to salt stress. …


Ecophysiological Responses Of Herbaceous Plants To The Presence Or Absence Of Amorpha Canescens In A Nebraska Sandhills Grassland, Jessica L. Milby Dec 2011

Ecophysiological Responses Of Herbaceous Plants To The Presence Or Absence Of Amorpha Canescens In A Nebraska Sandhills Grassland, Jessica L. Milby

School of Natural Resources: Dissertations, Theses, and Student Research

Deeply-rooted shrubs are a common component of grasslands. This study investigated the ecophysiological role of Amorpha canescens, a common leguminous shrub, in Sandhills grassland, and response of herbaceous plants to the presence or absence of A. canescens. Two sites were selected for the study at the Gudmundsen Sandhills Laboratory near Whitman, Nebraska – one with A. canescens (G-L) and one without (G-NL) A. canescens. Plant canopy cover and aboveground biomass were characterized on both sites in June and August 2010. Seasonal trends in net photosynthesis (A), stomatal conductance (gs), transpiration (E), water use efficiency (WUE), and predawn …


Studying The Handling Of Heat Stressed Cattle Using The Additive Bi-Logistic Model To Fit Body Temperature, Fan Yang Dec 2011

Studying The Handling Of Heat Stressed Cattle Using The Additive Bi-Logistic Model To Fit Body Temperature, Fan Yang

Department of Statistics: Dissertations, Theses, and Student Research

Daily activities consume the energy of heifers, subsequently causing an elevation of body temperature, depending on the ambient conditions. A better understanding of the dynamics of body temperature (Tb) would be helpful when deciding how to process and handle heifers. It would also lead to specific recommendations on moving heifers under different ambient conditions, especially during the summer. In this study, a bi-logistic mixed model is used to describe the dynamics of Tb during the moving event. Data were taken from heifers in pens located at different distances from the heifer work station on four separate summer days under hot …


Quantum Mechanical And Molecular Mechanical Study Of Solvent Effects, Dejun Si Dec 2011

Quantum Mechanical And Molecular Mechanical Study Of Solvent Effects, Dejun Si

Department of Chemistry: Dissertations, Theses, and Student Research

Intermolecular interaction and solvent effects play important roles in determining physical and chemical properties of molecular systems, and must be considered in relevant quantum mechanical (QM) calculations. Due to the high computational cost, full and rigorous QM treatment of both solute and solvent molecules is impractical. Computationally efficient molecular mechanical (MM) methods can be used to describe solvent effects, and combined into QM methods to formulate QM/MM methods. Classical force field method and reaction-field method are the two most popular MM methods. However, the issue of effectively combining MM methods with high-level QM methods remains unsolved. This thesis presents several …


Gold Nanoparticle Generation Using In Situ Reduction On A Photoresist Polymer Substrate, Christopher J. Clukay Dec 2011

Gold Nanoparticle Generation Using In Situ Reduction On A Photoresist Polymer Substrate, Christopher J. Clukay

HIM 1990-2015

This report presents evidence that in-situ reduction of metal ions bound to a cross-linked polymer surface does not always result in nanoparticle formation solely at the interface, as is commonly assumed, but also as much as 40 nm deep within the polymer matrix. Tetrachloroaurate ions were bound using a variety of multi-functional amines to cured films of SU-8 -- a cross-linkable epoxide frequently used for micro- and nanofabrication -- and then treated using one of several reducing agents. The resulting gold-nanoparticle decorated films were examined by X-ray photoelectron spectroscopy and by plan-view and cross-sectional transmission electron microscopy. Reduction using sodium …