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Part I : Isolation Of Dipentyl 2-(4-(Pentan-3-Yl) Phenyl) Malonate From Sanguisorba Officinalis Labill Part Ii: Synthesis Of A Novel Family Of Ethers Of Podocarpic Acid, Manjeera Yalavarty Jan 2005

Part I : Isolation Of Dipentyl 2-(4-(Pentan-3-Yl) Phenyl) Malonate From Sanguisorba Officinalis Labill Part Ii: Synthesis Of A Novel Family Of Ethers Of Podocarpic Acid, Manjeera Yalavarty

Electronic Theses and Dissertations

The goal of part I of this thesis was to isolate pure anti cancer compounds from the Russian plant Sanguisorba officinalis. This plant was selected for investigation because it showed 100% activity against leukemia (L1210 mouse leukemia cells) during the preliminary screening of approximately 100 Russian plant extracts. This work has resulted in the isolation of novel compound 11 using traditional chromatography techniques. Compound 11 was characterized with spectroscopic techniques such as IR, 1H NMR, 13C NMR, DEPT, DQCOSY and MS. Compound 11 was assigned the structure dipentyl 2-(4-(pentan-3-yl) phenyl) malonate. The goal of part II of this thesis was …

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Instrumented Nanoindentation Studies Of Deformation In Shape Memory Alloys, Sudhir Rajagopalan Jan 2005

Instrumented Nanoindentation Studies Of Deformation In Shape Memory Alloys, Sudhir Rajagopalan

Electronic Theses and Dissertations

Near equi-atomic nickel titanium (NiTi) shape memory alloys (SMAs) are a class of materials characterized by their unique deformation behavior. In these alloys, deformation mechanisms such as mechanical twinning and stress induced phase transformation between a high symmetry phase (austenite) and a low symmetry phase (martensite) additionally occur and influence mechanical behavior and thus their functionality. Consequently, applications of SMAs usually call for precise phase transformation temperatures, which depend on the thermomechanical history and the composition of the alloy. Instrumented indentation, inherently a mechanical characterization technique for small sampling volumes, offers a cost effective means of empirically testing SMAs in …

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Contributions To Automatic Particle Identification In Electron Micrographs: Algorithms, Implementation, And Applications, Vivek Singh Jan 2005

Contributions To Automatic Particle Identification In Electron Micrographs: Algorithms, Implementation, And Applications, Vivek Singh

Electronic Theses and Dissertations

Three dimensional reconstruction of large macromolecules like viruses at resolutions below 8 Ã… - 10 Ã… requires a large set of projection images and the particle identification step becomes a bottleneck. Several automatic and semi-automatic particle detection algorithms have been developed along the years. We present a general technique designed to automatically identify the projection images of particles. The method utilizes Markov random field modelling of the projected images and involves a preprocessing of electron micrographs followed by image segmentation and post processing for boxing of the particle projections. Due to the typically extensive computational requirements for extracting hundreds of …

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Vibration Analysis Of Carbon Nanotube Using Continuum Model And Finite Element Model, Hari Subramaniam Jan 2005

Vibration Analysis Of Carbon Nanotube Using Continuum Model And Finite Element Model, Hari Subramaniam

Electronic Theses and Dissertations

The main objective of the thesis is to propose the methods of determining vibration behavior of carbon nanotubes (CNTs) using continuum models and finite element models. Secondary objective is to find the effect of van der Waals force on vibration of multiwalled carbon nanotubes . The study of vibration behavior of CNTs is important because of their potential engineering applications such as nano-mechanical resonators and tips of scanning probe instruments where they are subjected to mechanical vibrations. Continuum modeling is based on an elastic beam model. The interlayer van der Waals interactions are represented by Lennard-Jones potential. In finite element …

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Cascading Effects Of Predator Removal On The Ecology Of Sea Turtle Nesting Beaches, Brandon Barton Jan 2005

Cascading Effects Of Predator Removal On The Ecology Of Sea Turtle Nesting Beaches, Brandon Barton

Electronic Theses and Dissertations

Traditional views of food web dynamics have characterized species interactions as linear and direct. However, modern food web theory suggests that interactions can also be nonlinear and indirect, so that disturbance at one trophic level is transmitted throughout the community. Many previous studies have demonstrated that the removal of top predators from terrestrial ecosystems can have broad-scale impacts on community ecology. I examined the direct and indirect effects of raccoon removal from sea turtle nesting beaches in east-central Florida during the summers of 2003 and 2004. Raccoon and ghost crab predation are among the highest causes of egg mortality for …

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Assessing The Impact Of University Technology Incubator Practices On Client Performance, Thomas O'Neal Jan 2005

Assessing The Impact Of University Technology Incubator Practices On Client Performance, Thomas O'Neal

Electronic Theses and Dissertations

This research is designed to distinguish and describe or explain incubator practices that affect the performance of incubator clients of university technology incubator programs. The research focuses on understanding which practices significantly contribute to increasing job creation for the firms located in university based technology incubators. An increasing number of communities are embracing economic development strategies that target the high tech sector with high wage, high value jobs as a way to diversify their economies and boost local and regional economies. New economic development strategies include the notion of a creation strategy or "growing your own" instead of relying on …

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Advances In The Opto-Mechanical Design And Alignment Of The Hehsi Imaging Spectrometer Based On A Sagnac Interferometer, Michael Stuart Schreiber Jan 2005

Advances In The Opto-Mechanical Design And Alignment Of The Hehsi Imaging Spectrometer Based On A Sagnac Interferometer, Michael Stuart Schreiber

Electronic Theses and Dissertations

The High Efficiency HyperSpectral Imager (HEHSI) is a Fourier Transform hyperspectral imager based on a Sagnac interferometer. This thesis research concentrates on the design upgrade and calibration of HEHSI from a proof of concept instrument to a prototype field instrument. Stability is enhanced by removing degrees of freedom and alignment is enhanced by providing for in-situ adjustments. The use of off the shelf components allows for reduced development time and cost constraints. HEHSI is capable of multiple configurations to accommodate sensors and optics with specialized capabilities for multiple wavelength ranges and viewing conditions. With a spectral response of 400 to …

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Confocal Laser Scanning Microscopy As A Tool For The Investigation Of Tetracycline Fluorescence In Archaeologicalhuman Bone, Corey Maggiano Jan 2005

Confocal Laser Scanning Microscopy As A Tool For The Investigation Of Tetracycline Fluorescence In Archaeologicalhuman Bone, Corey Maggiano

Electronic Theses and Dissertations

Fluorochromes such as tetracycline have been used to label bone for histomorphometric analysis, measuring bone formation, growth, maintenance, and pathology. More recently, similar fluorescence has been observed in ancient human bone. Attributed to tetracycline (TC) exposure, this phenomenon could affect various aspects of health during life and/or preservation of remains postmortem. Standard epifluorescence microscopy is the most common tool employed in the analysis of these labels. Though valuable, this technique is limited by its inability to penetrate bone three-dimensionally and its inclusion of out-of-focus light, possibly disrupting accurate analysis. Confocal Laser Scanning Microscopy (CLSM) has been demonstrated as a valuable …

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A Novel Binding Interaction For The Paxillin Ld3 Motif: Paxillin Ld3 Mediates Merlin-Paxillin Binding At Paxillin Binding Domain 1, Sandra E. Beattie Geden Jan 2005

A Novel Binding Interaction For The Paxillin Ld3 Motif: Paxillin Ld3 Mediates Merlin-Paxillin Binding At Paxillin Binding Domain 1, Sandra E. Beattie Geden

Electronic Theses and Dissertations

Neurofibromatosis type 2, an autosomal dominant genetic disorder, causes predisposed individuals to develop various benign central and peripheral nervous system tumors. The characteristic tumors of this disease are schwannomas, which are tumors of the Schwann cells, typically on the vestibular nerve. These and the other associated tumors slowly compress nervous system structures causing deafness and loss of balance, resulting in an average life-span of less than 40 years. The product of the Nf2 gene is the protein named merlin or schwannomin. In individuals diagnosed with NF2, merlin is either absent or mutated to the point of inactivation. As such, merlin …

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The Influence Of Past Abuse On Heterosexual Cohabiting Couples' Relationship Types, Page Thanasiu Jan 2005

The Influence Of Past Abuse On Heterosexual Cohabiting Couples' Relationship Types, Page Thanasiu

Electronic Theses and Dissertations

This study investigated the influence of past witnessed or experienced abuse on heterosexual cohabiting couples' Premarital Personal and Relationship Evaluation for Cohabiting Couples (PREPARE-CC) couple relationship types. The researcher utilized preexisting data from 5,000 cohabiting couples who had previously participated in the PREPARE marriage preparation program and had completed the PREPARE-CC inventory including a demographic section that elicited information about past abuse. Discriminant analysis was conducted in SPSS to answer the question of whether the presence of past witnessed or experienced abuse could successfully predict relationship type among cohabiting couples. Results of the discriminant analysis yielded no significant ability to …

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Simulation Studies Of Self-Assembly And Phase Diagram Of Amphiphilic Molecules, Geuorgui Kostadinov Bourov Jan 2005

Simulation Studies Of Self-Assembly And Phase Diagram Of Amphiphilic Molecules, Geuorgui Kostadinov Bourov

Electronic Theses and Dissertations

The aim of this dissertation is to investigate self-assembled structures and the phase diagram of amphiphilic molecules of diverse geometric shapes using a number of different computer simulation methods. The semi-realistic coarse-grained model, used extensively for simulation of polymers and surfactant molecules, is adopted in an off-lattice approach to study how the geometric structure of amphiphiles affects the aggregation properties. The results of simulations show that the model system behavior is consistent with theoretical predictions, experiments and lattice simulation models. We demonstrate that by modifying the geometry of the molecules, self-assembled aggregates are altered in a way close to theoretical …

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Regional Readiness For Intelligence Information Sharing To Support Homeland Security, Christine Genet Kemp Jan 2005

Regional Readiness For Intelligence Information Sharing To Support Homeland Security, Christine Genet Kemp

Electronic Theses and Dissertations

The Markle Task Force on National Security in the Information Age was created to produce recommendations on how to best leverage intelligence and information to improve security without compromising existing civil liberties. Their second report proposed that the government set up an information-sharing network using currently available technology to improve our ability to prevent terrorist attacks, while protecting civil liberties. The Markle recommendations have been incorporated into the recent Intelligence Reform and Terrorism Prevention Act of 2004. The proposition is that the Markle task force recommendations are sufficient to achieve the required data integration in the United States. To affirm …

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An Inquiry Into Discourse Choices As Indicators Of Gender Attitudes In A Non-Profit Conservative Christian Business, Dawn Marie Kruger Jan 2005

An Inquiry Into Discourse Choices As Indicators Of Gender Attitudes In A Non-Profit Conservative Christian Business, Dawn Marie Kruger

Electronic Theses and Dissertations

This paper is an inquiry into the discourse styles of men and women who work together in a conservative Protestant Christian business. Many conservative Protestant Christian churches teach that the Bible forbids women from holding positions of authority over men. Yet in the communications department of this particular business, women fill the top three management positions, supervising a mixed-gender staff of 15. Research has shown that men and women subconsciously use language markers that indicate personal attitudes toward the same and the opposite genders. This research project draws on that information while it analyzes the oral and electronic discourse of …

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Affective Design In Technical Communication, Michael Alan Rosen Jan 2005

Affective Design In Technical Communication, Michael Alan Rosen

Electronic Theses and Dissertations

Traditional human-computer interaction (HCI) is based on 'cold' models of user cognition; that is, models of users as purely rational beings based on the information processing metaphor; however, an emerging perspective suggests that for the field of HCI to mature, its practitioners must adopt models of users that consider broader human needs and capabilities. Affective design is an umbrella term for research and practice being conducted in diverse domains, all with the common thread of integrating emotional aspects of use into the creation of information products. This thesis provides a review of the current state of the art in affective …

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The Effects Of A Project-Based Mathematics Curriculum On Middle School Students' Intended Career Paths Related To Science, Technology, Engineering And Mathematics, Barbara Clanton Jan 2005

The Effects Of A Project-Based Mathematics Curriculum On Middle School Students' Intended Career Paths Related To Science, Technology, Engineering And Mathematics, Barbara Clanton

Electronic Theses and Dissertations

This study is an examination of whether a project-based mathematics curriculum would influence students' intended career paths related to science, technology, engineering, and mathematics (STEM) endeavors; perceived usefulness of mathematics; and perceived competence in doing mathematics. A review of the literature revealed that there are many shortages of professionals in STEM fields. United States women and men are not pursuing STEM endeavors in great numbers and the U.S. relies heavily on international students to fill this gap. The literature revealed that the girls who do not pursue STEM endeavors in great numbers do not perceive mathematics as a useful endeavor …

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Assessment And In Vitro Repair Of Damaged Dna Templates From Forensic Stains, Ashley Hall Jan 2005

Assessment And In Vitro Repair Of Damaged Dna Templates From Forensic Stains, Ashley Hall

Electronic Theses and Dissertations

DNA extracted from biological stains is often intractable to analysis. This may due to a number of factors including a low copy number (LCN) of starting molecules, the presence of soluble inhibitors or damaged DNA templates. Remedies may be available to the forensic scientist to deal with LCN templates and soluble inhibitors but none presently exist for damaged DNA. In fact, only recently has the biochemical nature, the extent of DNA damage in physiological stains and the point at which the damage inflicted upon a particular sample precludes the ability to obtain a genetic profile for purposes of identification been …

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Time Estimation And Hand Preference, Maria Rodriguez Jan 2005

Time Estimation And Hand Preference, Maria Rodriguez

Electronic Theses and Dissertations

This work examines the effect of participants' gender and handedness on the perception of short intervals of time. The time estimation task consisted of an empty production procedure with forty trials at each of four intervals of one, three, seven, and twenty seconds. The four target intervals represent a natural logarithmic progression and a series that bracket important temporal thresholds. The order of presentation of those intervals was randomized across participants but yoked across the sexes in each of the respective dominant hand groups. The two between-subject factors, with two levels each, were sex and handedness. Participants produced forty estimates …

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A Probe Into Learning Approaches And Attitudes Towards Technology-Enhanced Language Learning (Tell) In Chinese Instruction, Rong Yuan Jan 2005

A Probe Into Learning Approaches And Attitudes Towards Technology-Enhanced Language Learning (Tell) In Chinese Instruction, Rong Yuan

Electronic Theses and Dissertations

This quantitative research, carried out at the military environment at the Defense Language Institute investigated whether learning approaches could predict learners' language proficiency and learners' attitude towards technology-enhanced language learning (TELL). In addition, it also examined whether learners' demographic factors, such as age, educational backgrounds, prior experience in foreign language learning and in TELL as well as their ability to use PC and the World Wide Web could predict the above mentioned language proficiency and attitude. A cluster sampling method was adopted and data was collected in four Chinese departments at the institute. Both the learning approaches inventory ASSIST and …

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Structural Study Of Disease Related Proteins, Ayse Sinem Ozyurt Jan 2005

Structural Study Of Disease Related Proteins, Ayse Sinem Ozyurt

Electronic Theses and Dissertations

The availability of complete sequences for the genomes of many organisms changes the researcher's attention from genome sequencing to finding the function of gene products, the proteins. The three dimensional (3D) structure of a protein is helpful to understand its function, because tertiary structure is more conserved in evolution than sequence. The 3D structures can be found quickly by using high-throughput (HT) methods for protein expression, purification, characterization and structure determination. This process is very challenging in every step. Therefore we selected nearly 200 cancer related proteins as targets to see the difficulties in trying to determine the web predicted …

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Physical And Behavioral Complaints In Children With Attention-Deficit/Hyperactivity Disorder (Adhd): Paradoxical Effects Of Methylphenidate, Maria M. Coiro Jan 2005

Physical And Behavioral Complaints In Children With Attention-Deficit/Hyperactivity Disorder (Adhd): Paradoxical Effects Of Methylphenidate, Maria M. Coiro

Electronic Theses and Dissertations

Hypotheses concerning paradoxical, psychostimulant-related side effects experienced by ADHD children were examined in the context of a double-blind, placebo-controlled, within subject (crossover) experimental design. Results revealed that behavioral and physical complaints were significantly higher under baseline relative to placebo and the four methylphenidate (MPH) conditions (5-mg, 10-mg, 15-mg, 20-mg) across three symptom categories: ADHD core/secondary symptoms, symptoms common to all children, and symptoms highly specific to MPH. No significant differences were found among active drug conditions. Implications of these findings for assessing and monitoring potential treatment emergent symptoms in children are discussed.

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The Effects Of An Academic Support Services Unit On The Grade Point Average For Students Admitted On Probation, Keith Branham Jan 2005

The Effects Of An Academic Support Services Unit On The Grade Point Average For Students Admitted On Probation, Keith Branham

Electronic Theses and Dissertations

The goal of this research was to examine the effects, if any, the programs available from an Academic Support Services unit of a small, private, liberal arts college might have on the grade point averages of students admitted on probation over two major semesters. The assumption was that the students who utilized the services of the Academic Center for Excellence would demonstrate more increases in GPA than students who did not utilize the services. The literature review of this study found that, although there were many factors and student characteristics that could predict and explain student achievement in course work, …

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Tunable Liquid Crystal Photonic Devices, Yun-Hsing Fan Jan 2005

Tunable Liquid Crystal Photonic Devices, Yun-Hsing Fan

Electronic Theses and Dissertations

Liquid crystal (LC)-based adaptive optics are important for information processing, optical interconnections, photonics, integrated optics, and optical communications due to their tunable optical properties. In this dissertation, we describe novel liquid crystal photonic devices and their fabrication methods. The devices presented include inhomogeneous polymer-dispersed liquid crystal (PDLC), polymer network liquid crystals (PNLC) and phase-separated composite film (PSCOF). Liquid crystal/polymer composites could exist in different forms depending on the fabrication conditions. In Chap. 3, we demonstrate a novel nanoscale PDLC device that has inhomogeneous droplet size distribution. In such a PDLC, the inhomogeneous droplet size distribution is obtained by exposing the …

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Self-Assembled Supramolecular Structures Of Chiral Phospholipids: Structure, Mechanical Properties And Patterning, Nidhi Mahajan Jan 2005

Self-Assembled Supramolecular Structures Of Chiral Phospholipids: Structure, Mechanical Properties And Patterning, Nidhi Mahajan

Electronic Theses and Dissertations

Lipid molecule is well known natural building block to form different supramolecular structures with specific shape, size and functionality. In my thesis work, I have used DC8,9PC 1,2-bis(tricosa-10,12-dinoyl)-sn-glycero-3-phosphocholine), a type of chiral lipid to form the vesicles, tubules and ribbons . By using Atomic Force Microscope, I have studied the morphological features of these particular structures. Also, the mechanical properties of lipid tubules have been studied using AFM. Softlithography has been used to pattern the lipid vesicles and tubules into 2-dimensional and 3-dimensional ordered arrays. The structure of self-assembled hollow spherical vesicles was studied using AFM. The applications of soft …

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A Dynamic Model Of The Human/Cooling System/Clothing/Environment System, Zhengxiang Pu Jan 2005

A Dynamic Model Of The Human/Cooling System/Clothing/Environment System, Zhengxiang Pu

Electronic Theses and Dissertations

The human body compensates well for moderate climatic heat stress, but artificial environments often block or overwhelm physiological defense mechanism. Personal protective equipment (PPE) is one of sources of heat stress. It protects individual from chemical, physical, or biological hazards, but the high thermal insulation and low vapor permeability of PPE may also lead to substantial heat stress. Personal cooling is widely used to alleviate heat stress, especially for those situations where ambient environmental cooling is not economically viable or feasible. It is important to predict the physiological responses of a person wearing PPE with personal cooling to make sure …

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System Design And Optimization Of Optical Coherence Tomography, Avni Ceyhun Akcay Jan 2005

System Design And Optimization Of Optical Coherence Tomography, Avni Ceyhun Akcay

Electronic Theses and Dissertations

Optical coherence imaging, including tomography (OCT) and microscopy (OCM), has been a growing research field in biomedical optical imaging in the last decade. In this imaging modality, a broadband light source, thus of short temporal coherence length, is used to perform imaging via interferometry. A challenge in optical coherence imaging, as in any imaging system towards biomedical diagnosis, is the quantification of image quality and optimization of the system components, both a primary focus of this research. We concentrated our efforts on the optimization of the imaging system from two main standpoints: axial point spread function (PSF) and practical steps …

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Becoming Transcultural: Filling The Cultural And Communication Gap Within The Black American Community, Quanda Le Boldin Jan 2005

Becoming Transcultural: Filling The Cultural And Communication Gap Within The Black American Community, Quanda Le Boldin

Electronic Theses and Dissertations

The purpose of this study is to define transculturalism by exploring the Black experience through collectivism/individualism, Black identity and the ability to be transcultural. The study included 83 male and female Black American, college students, graduate students and college graduates. The participants answered a 4-part survey that measured collectivism/individualism, Black identity, the ability to be transcultural and minority hardships. Results revealed that the Pre-encounter, Immersion, Emersion and Internalization phases of Black identity are predictors of minority hardships. There were also significant results for the Internalization phase of Black identity and the ability to be transcultural. In conclusion, Black Americans that …

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Development And Validation Of The Beile Test Of Information Literacy For Education (B-Tiled), Penny Beile O'Neil Jan 2005

Development And Validation Of The Beile Test Of Information Literacy For Education (B-Tiled), Penny Beile O'Neil

Electronic Theses and Dissertations

Few constituencies exist where it is more important to produce information literate individuals than teacher candidates, yet rarely is it suggested that practitioners entering the field are adequately prepared to teach and model information literacy to their students. As a result, information literacy has been established as a key outcome by a number of teacher education accrediting bodies and professional associations. Corollary to this initiative is the effort to develop valid instruments that assess information literacy skills. Yet, at the time of this dissertation, no rigorously reviewed instruments were uncovered that measure the information literacy skills levels of teacher candidates. …

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An Inverse Algorithm To Estimate Thermal Contact Resistance, Jennifer Gill Jan 2005

An Inverse Algorithm To Estimate Thermal Contact Resistance, Jennifer Gill

Electronic Theses and Dissertations

Thermal systems often feature composite regions that are mechanically mated. In general, there exists a significant temperature drop across the interface between such regions which may be composed of similar or different materials. The parameter characterizing this temperature drop is the thermal contact resistance, which is defined as the ratio of the temperature drop to the heat flux normal to the interface. The thermal contact resistance is due to roughness effects between mating surfaces which cause certain regions of the mating surfaces to loose contact thereby creating gaps. In these gap regions, the principal modes of heat transfer are conduction …

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Optical Wave Propagation In Discrete Waveguide Arrays, Jared Hudock Jan 2005

Optical Wave Propagation In Discrete Waveguide Arrays, Jared Hudock

Electronic Theses and Dissertations

The propagation dynamics of light in optical waveguide arrays is characteristic of that encountered in discrete systems. As a result, it is possible to engineer the diffraction properties of such structures, which leads to the ability to control the flow of light in ways that are impossible in continuous media. In this work, a detailed theoretical investigation of both linear and nonlinear optical wave propagation in one- and two-dimensional waveguide lattices is presented. The ability to completely overcome the effects of discrete diffraction through the mutual trapping of two orthogonally polarized coherent beams interacting in Kerr nonlinear arrays of birefringent …

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Micromachined Electrochemical Sensors For Hydrogen Peroxide And Chlorine Detection, Anjum Mehta Jan 2005

Micromachined Electrochemical Sensors For Hydrogen Peroxide And Chlorine Detection, Anjum Mehta

Electronic Theses and Dissertations

Hydrogen peroxide and chlorine detection is critical for many biological and environmental applications. Hydrogen peroxide plays important roles in a variety of fields including plant physiology, medical, environmental and biochemical applications. Its role in plant defense and signal transduction, diseases such as Parkinson's and Alzhemier's, industrial processes such as disinfection and wastewater treatment and biochemical enzymatic reactions is critical. Given the gamut of areas that hydrogen peroxide is a key component of; its detection assumes great importance. Similarly chlorine has long been used as a disinfectant for making drinking water safe, but excessive chlorination is an environmental and health hazard …

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