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Particle Streak Velocimetry: A Diagnostic For High Speed Flows, Jared D. Willits May 2018

Particle Streak Velocimetry: A Diagnostic For High Speed Flows, Jared D. Willits

Open Access Dissertations

This work describes the development and implementation of a novel velocimetry technique to probe the exhaust flow of a cold gas thruster. The diagnostic combines the advantages of standard particle velocimetry techniques and the ultra-fast imaging capabilities of a streak camera to probe high speed flows near continuously with improved spatial and velocity resolution compared to Particle Image Velocimetry. This “Particle Streak Velocimetry” technique tracks illuminated seed particles at up to 4.2 GHz allowing time-resolved measurement of one-dimensional flows exceeding 2000 m/s as are found in rocket nozzles and many other applications (US Provisional Patent filed 05/19/16). Single frame images …

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It's All Local: Civil Society And The Cdbg Program, Sara L. Wiest May 2018

It's All Local: Civil Society And The Cdbg Program, Sara L. Wiest

Open Access Dissertations

This research seeks to explain contrasting patterns of population stability and decline at both the city and neighborhood levels. Existing research on urban decline identifies several factors that can facilitate or impede population stability, including: the amount of socioeconomic disadvantage, the physical and economic characteristics of a city, local government responsiveness, and the strength of civil society. Using a mixed methods approach combining multilevel modeling and spatial analysis techniques, I test the hypothesis that stronger civil society, characterized by greater collective capacity and a denser organizational resource base, is the key determinant in whether a city will stabilize, grow, or …

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Bioconjugation Techniques To Construct Spontaneously Assembling Dna-Enzyme Macromolecules, Malithi Wickramathilaka May 2018

Bioconjugation Techniques To Construct Spontaneously Assembling Dna-Enzyme Macromolecules, Malithi Wickramathilaka

Open Access Dissertations

In the past two decades, crosslinking has been a popular choice in synthesizing bioconjugatesinthefieldsofbiotechnology,medicaldiagnostics,andgeneticscreening.However, their efficacyin synthesizing the desired bioconjugates is scarcely analyzed and documented. The scope of this investigation encompassed studying covalent bioconjugation techniques, and determining the structural characteristics of the bioconjugates formed via several crosslinking strategies. The major goal of the study was to determine relatively inexpensive, less complex, and universal bioconjugation techniques with the flexibility to control the distance between wild-type enzymes. In this investigation, three different crosslinkers were studied to determine the efficacy of crosslinking biological molecules. In the first aim of the study, an adapted …

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Punishment Of Public Corruption In China And The United States, Linjing Wang May 2018

Punishment Of Public Corruption In China And The United States, Linjing Wang

Open Access Dissertations

Corruption is pervasive in many countries. However, the most effective punishment to deter corruption remains unknown. Some have suggested that the death penalty is required to reduce corruption and ensure clean government. However, research shows that the likelihood of punishment is the strongest factor, not the severity of the punishment. It requires large social costs, such as expenditure on policemen, court personnel, and specialized monitoring equipment, to improve the probability of punishment. Can elevation of the severity of punishment be a good substitute? The empirical results from this dissertation suggest that the probability of punishing corruption, i.e., how likely a …

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Multiscale Microstructure Modeling And Design Of Electrochemomechanics In Lithium-Ion Batteries, Linmin Wu May 2018

Multiscale Microstructure Modeling And Design Of Electrochemomechanics In Lithium-Ion Batteries, Linmin Wu

Open Access Dissertations

This thesis investigates the electro-chemo-mechanics behavior of electrodes in lithium ion batteries. One of the critical challenges in advanced lithium ion batteries is preventing fracture and mechanical failure of electrodes during lithium insertion and deinsertion. The large volume expansion, phase transition, and the associated Li diffusion induced stresses within electrode materials can lead to their fracture and failure. Numerical simulations have the potentials for design optimization of lithium ion batteries. For traditional Newman’s model, it is limited by the assumption that the electrodes are constructed with uniformly distributed spherical particles of equal size. To consider the influence of real microstrucutural …

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Understanding China's Soybean Boom From A Global Perspective, Guolin Yao May 2018

Understanding China's Soybean Boom From A Global Perspective, Guolin Yao

Open Access Dissertations

China’s soybean demand boom in the past two decades has been very dramatic. It involves socioeconomic and environmental interactions of multi-coupled systems. Over this period, China doubled its GDP, and the ensuing income growth generated strong growth in the demand for livestock products -- a major consumer of soybean meals. In addition, the goal of producing more meat and milk boosted protein content requirements in feed formulations and intensified China’s soybean meal demands. Brazil and Argentina stepped in to satisfy this increased demand. In the case of Brazil, rapid technical change, coupled with the expansion of cultivated area, played a …

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Higher-Order Random Walk Methods For Data Analysis, Tao Wu May 2018

Higher-Order Random Walk Methods For Data Analysis, Tao Wu

Open Access Dissertations

Markov random walk models are powerful analytical tools for multiple areas in machine learning, numerical optimizations and data mining tasks. The key assumption of a frst-order Markov chain is memorylessness, which restricts the dependence of the transition distribution to the current state only. However in many applications, this assumption is not appropriate. We propose a set of higher-order random walk techniques and discuss their applications to tensor co-clustering, user trails modeling, and solving linear systems. First, we develop a new random walk model that we call the super-spacey random surfer, which simultaneously clusters the rows, columns, and slices of a …

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Digital Image Segmentation And On–Line Print Quality Diagnostics, Zuguang Xiao May 2018

Digital Image Segmentation And On–Line Print Quality Diagnostics, Zuguang Xiao

Open Access Dissertations

During the electrophotographic (EP) process for a modern laser printer, object-oriented halftoning is sometimes used which renders an input raster page with different halftone screen frequencies according to an object map; this approach can reduce the print artifacts for the smooth areas as well as preserve the fine details of a page. Object map can be directly extracted from the page description language (PDL), but most of the time, it is not correctly generated. For the first part of this thesis, we introduce a new object generation algorithm that generates an object map from scratch purely based on a raster …

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Lewis Acid-Mediated Diastereoselective Synthesis Of Medium-Sized Cyclic Ethers And Studies Towards The Synthesis Of Plakortolide E And 6-Epiplakortolide E, Anthony J. Tomaine May 2018

Lewis Acid-Mediated Diastereoselective Synthesis Of Medium-Sized Cyclic Ethers And Studies Towards The Synthesis Of Plakortolide E And 6-Epiplakortolide E, Anthony J. Tomaine

Open Access Dissertations

The Lewis acid-mediated synthesis of medium-sized cyclic ethers has been achieved in a diastereoselective manner. Using TMSOTf or BF3•OEt2, we developed a novel protocol for the intermolecular synthesis of eight-membered cyclic ethers (oxocenes) via Prins-type cyclization. This methodology displays a unique approach towards 2,4,8-trisubstiituted oxocene cores, with good yields and excellent diastereoselectivity. We have also expanded this protocol to show applicability towards the synthesis of seven-membered rings (oxepines and oxepanes). Progress studies towards the synthesis of plakortolide E and 6-epiplakortolide E are described. Featuring a bicyclic peroxylactone, these compounds are of interest due to their potential antimalarial activity. A key …

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Advanced Imaging Techniques For Point-Measurement Analysis Of Pharmaceutical Materials, Shijie Zhang May 2018

Advanced Imaging Techniques For Point-Measurement Analysis Of Pharmaceutical Materials, Shijie Zhang

Open Access Dissertations

Drugs are an essential element protecting human lives from many diseases such as cancer, diabetes, and cardiovascular disorders. One of the highlights in drug development in recent years is the establishment of rational drug design: a collection of various multi-disciplinary approaches that at the core, focus on designing molecules with specific properties for identified targets and biomolecules with known functional roles and structural information. The candidate molecules will then go through a series of examinations to characterize their physiochemical properties, and an iterative process is used to improve the design of the drug to achieve desirable attributes. The time consuming …

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Context-Preserving Visual Analytics Of Multi-Scale Spatial Aggregation., Jiawei Zhang May 2018

Context-Preserving Visual Analytics Of Multi-Scale Spatial Aggregation., Jiawei Zhang

Open Access Dissertations

Spatial datasets (i.e., location-based social media, crime incident reports, and demographic data) often exhibit varied distribution patterns at multiple spatial scales. Examining these patterns across different scales enhances the understanding from global to local perspectives and offers new insights into the nature of various spatial phenomena. Conventional navigation techniques in such multi-scale data-rich spaces are often inefficient, require users to choose between an overview or detailed information, and do not support identifying spatial patterns at varying scales. In this work, we present a context-preserving visual analytics technique that aggregates spatial datasets into hierarchical clusters and visualizes the multi-scale aggregates in …

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Quantifying Nitrogen Fixation And Nitrous Oxide Emissions In Global Natural Terrestrial Ecosystems Using Trait-Based Biogeochemistry Models., Tong Yu May 2018

Quantifying Nitrogen Fixation And Nitrous Oxide Emissions In Global Natural Terrestrial Ecosystems Using Trait-Based Biogeochemistry Models., Tong Yu

Open Access Dissertations

Nitrous oxide (N2O) contributes to the global climate system and is the third most important greenhouse gas. It is also one of the largest ozone-depleting substances emitted from the biosphere, with great influences on the atmosphere. Therefore, it is important to quantify its emissions from soils in natural terrestrial ecosystems. This dissertation research quantifies N2O emissions from the global natural ecosystems by explicitly considering the influence of soil microbial activities. This dissertation consists of three studies. I first develop a N2O emission model based on an extant process-based biogeochemistry model, the Terrestrial Ecosystem Model, to estimate soil N2O emissions in …

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Biofluid Analysis With Novel Targeted Mass Spectrometry Methods, Karen E. Yannell May 2018

Biofluid Analysis With Novel Targeted Mass Spectrometry Methods, Karen E. Yannell

Open Access Dissertations

Mass spectrometry (MS) provides a high level of sensitivity and specificity to accurately and precisely identify and quantify analytes in a complex matrix. In clinical samples, this instrument is often used to quantify drugs or discover new biomarkers. However, existing workflows routinely use chromatography to separate the components of a sample. These methods lack speed and are expensive, neither of which are ideal characteristics for point of care or high throughput analysis. Paper spray (PS) is an ambient ionization technique that combines the sample preparation and ionization steps, to directly spray a complex sample into a MS. The MS provides …

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Computational Modeling Of (De)-Solvation Effects And Protein Flexibility In Protein-Ligand Binding Using Molecular Dynamics Simulations, Ying Yang May 2018

Computational Modeling Of (De)-Solvation Effects And Protein Flexibility In Protein-Ligand Binding Using Molecular Dynamics Simulations, Ying Yang

Open Access Dissertations

Water is a crucial participant in virtually all cellular functions. Evidently, water molecules in the binding site contribute significantly to the strength of intermolecular interactions in the aqueous phase by mediating protein-ligand interactions, solvating and de-solvating both ligand and protein upon protein-ligand dissociation and association. Recently many published studies use water distributions in the binding site to retrospectively explain and rationalize unexpected trends in structure-activity relationships (SAR). However, traditional approaches cannot quantitatively predict the thermodynamic properties of water molecules in the binding sites and its associated contribution to the binding free energy of a ligand. We have developed and validated …

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Object-Oriented User Interface Customization Framework: Customizing Complex User Interfaces To Improve Usability And User Performance., Le Zhang May 2018

Object-Oriented User Interface Customization Framework: Customizing Complex User Interfaces To Improve Usability And User Performance., Le Zhang

Open Access Dissertations

The objective of this research is to use four individual studies to validate the Object-Oriented User Interface Customization (OOUIC) framework for solving three challenges of implementing User Interface (UI) customization in Complex Information System (CIS) and improving usability and user performance of complex UI. The first challenge is that adaptive UI, which tailors a UI to be relevant to a user role, has difficulties in identifying numerous users’ complex requirements and simplifying UIs for them. The second challenge is that adaptive UI cannot satisfy every individual’s unique needs. The third challenge is that adaptable UI, which allows a user to …

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Quantifying The Potential Of Climate Mitigation And Adaptation In The United States Agricultural System With Model-Data Integration, Peng Zhu May 2018

Quantifying The Potential Of Climate Mitigation And Adaptation In The United States Agricultural System With Model-Data Integration, Peng Zhu

Open Access Dissertations

Agriculture is an important sector of U.S. economy. Faced with increasing global food demand driven by population boom, it is necessary to sustain the increasing food production. However, agricultural system is inherently sensitive to climate change and multiple lines of evidence across different spatial scales implied that the future warming will decrease global food production. In this context, this thesis focused on US cropland to investigate its potential in climate mitigation and adaptation by synthesizing the multiple crop models, long term satellite data, official survey data and field experiment. The fundamental questions addressed by this dissertation are: (1) how will …

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Low Speed Flap-Bounding In Ornithopters And Its Inspiration On The Energy Efficient Flight Of Quadrotors, Yi Wang May 2018

Low Speed Flap-Bounding In Ornithopters And Its Inspiration On The Energy Efficient Flight Of Quadrotors, Yi Wang

Open Access Dissertations

Flap-bounding, a form of intermittent flight, is often exhibited by small birds over their entire range of flight speeds. The purpose of flap-bounding is unclear during low to medium speed (2 - 8 m/s) flight from a mechanical-power perspective: aerodynamic models suggest continuous flapping would require less power output and lower cost of transport. This thesis works towards the understanding of the advantages of flap-bounding and tries to employ the underlining principle to design quadrotor maneuver to improve power efficiency. To explore the functional significance of flap-bounding at low speeds, I measured body trajectory and kinematics of wings and tail …

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Modeling And Mitigation Of Wireless Communications Interference For Spectrum Sharing With Radar, David P. Zilz May 2018

Modeling And Mitigation Of Wireless Communications Interference For Spectrum Sharing With Radar, David P. Zilz

Open Access Dissertations

Due to both economic incentives and policy mandates, researchers increasingly face the challenge of enabling spectrum sharing between radar and wireless communications systems. In the past eight years, researchers have begun to suggest a wide variety of approaches to radar-communications spectrum sharing, ranging from transmitter design to receiver design, from spatial to temporal to other-dimensional multiplexing, and from cooperative to non-cooperative sharing. Within this diverse field of innovation, this dissertation makes two primary contributions. First, a model for wireless communications interference and its effects on adaptive-threshold radar detection is proposed. Based on both theoretical and empirical study, we find evidence …

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Approximating Properties Of Data Streams, Samson Zhou May 2018

Approximating Properties Of Data Streams, Samson Zhou

Open Access Dissertations

In this dissertation, we present algorithms that approximate properties in the data stream model, where elements of an underlying data set arrive sequentially, but algorithms must use space sublinear in the size of the underlying data set. We first study the problem of finding all k-periods of a length-n string S, presented as a data stream. S is said to have k-period p if its prefix of length n − p differs from its suffix of length n − p in at most k locations. We give algorithms to compute the k-periods of a string S using poly(k, log n) …

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College Readiness And Digital Badges: A Middle School Approach, Blake C. Nemelka May 2018

College Readiness And Digital Badges: A Middle School Approach, Blake C. Nemelka

Open Access Dissertations

Post-secondary education attainment results in higher salaries (Pew Research Center, 2014) and an increase in positive societal benefits (Baum, Ma, & Payea, 2013). Nevertheless, only 31% of U.S. citizens over the age of 25 have a bachelor’s degree (U.S. Census Bureau, 2014). While tradition would dictate the preparation for going to college begins in the later high school years (Gaertner & McClarty, 2015), a recent push has emerged for shifting the beginning of such conversations to middle school (Curry, Belser, & Binns, 2013; Gaertner & McClarty, 2015; Mattern, Allen, & Camara, 2016; Nemelka & Nemelka, 2016). Furthermore, advances in educational …

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The Effects Of Dietary Protein At Breakfast And Across The Day On Appetite Control & Satiety, Food Intake, And Sleep Quality, Jess A. Gwin May 2018

The Effects Of Dietary Protein At Breakfast And Across The Day On Appetite Control & Satiety, Food Intake, And Sleep Quality, Jess A. Gwin

Open Access Dissertations

The movement to adopt healthful lifestyle practices to reduce the prevalence of obesity and associated chronic diseases has garnered global interest [1]. As such, the desire to consume more protein-rich foods is a commonly used strategy due to the documented improvements in weight management observed with higher-protein (HP) diets, ranging from 1.2-1.6 g protein•kg body weight-1•d-1[2-6]. One postulated mechanism through which HP diets elicit greater weight (and fat) losses includes the improvements in ingestive behavior which appear to be mediated by a number of satiety-stimulating, physiological and/or hedonic pathways, and lead to reductions in daily food intake [3]. The main …

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Applications Of Multivariate Raman Spectroscopy, Sarah M. Matt May 2018

Applications Of Multivariate Raman Spectroscopy, Sarah M. Matt

Open Access Dissertations

The vibrational Raman spectrum of water can be used to probe changes in water structure as a function of temperature and due to solute-water interactions. We have demonstrated a diverse set of these applications by combining Raman spectroscopy with self-modeling curve resolution (SMCR). To begin with, the affinity of halogen anions for both benzene and pyridine was quantified by calculating ion partition coefficients based upon vibrational spectroscopic measurements. These partition coefficients were also found to be in good agreement with those obtained from MD simulations performed in collaboration with the Tobias group at University of California, Irvine. Next, we probed …

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Characterization Of Manifold Microchannel Heat Sinks During Two-Phase Operation, Kevin P. Drummond May 2018

Characterization Of Manifold Microchannel Heat Sinks During Two-Phase Operation, Kevin P. Drummond

Open Access Dissertations

High-heat-flux removal is necessary for next-generation microelectronic systems to operate more reliably and efficiently. The direct embedding of microchannel heat sinks into the heated substrate serves to reduce the parasitic thermal resistances due to contact and conduction resistances typically associated with the attachment of a separate heat sink. Manifold microchannel (MMC) heat sinks can dissipate high heat fluxes at moderate pressure drops, especially during two-phase operation. High-aspect-ratio microchannels allow for a large enhancement in heat transfer area. This work focuses on designing intrachip MMC heat sinks for high-heat-flux dissipation and to characterize the flow morphology present in the MMCs during …

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Global On-Line, Interactive And Simulated Learning Techniques Via Birs, Janet L. Fourman May 2018

Global On-Line, Interactive And Simulated Learning Techniques Via Birs, Janet L. Fourman

Open Access Dissertations

Role-playing simulations have been effective techniques to encourage global skills in the engineering and design classrooms. May, Wold and Moore (2014), defined global skills as student display of respect, recognition, adjustment and integration. Gray, Debs, Exter, and Krause (2016), took this one step further and looked-for empathy in the design classroom. This has yet to be realized in the regulatory science education realm. Therefore, there is a need for on-line, interactive regulatory science education focusing on global skill outcomes. To assess the gap, four sets of data are collected. The first set was a review of evaluations from a regulatory …

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Optical Studies Of Novel Electronic Materials, Nirajan Mandal May 2018

Optical Studies Of Novel Electronic Materials, Nirajan Mandal

Open Access Dissertations

We have made a Kerr rotation (KR) measurement instrument with a 635 nm laser that is sensitive enough to measure KR angle of few micro-radians. The KR instrument was used to study the current induced polarization rotation of light as it is reflected off the surface of topological insulator Bi2Te2Se (BTS221). In our experiment, we observe a linear response of Kerr rotation with current and the Kerr rotation for both s and p-polarized light is negative. From the dependence of this polarization rotation on the current in the TI sample, the angle of incidence of light and the light polarization, …

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Multi-Period Tradable Credit Schemes For Transportation And Environmental Applications, Seyedmohammad Miralinaghi May 2018

Multi-Period Tradable Credit Schemes For Transportation And Environmental Applications, Seyedmohammad Miralinaghi

Open Access Dissertations

Greenhouse gas (GHG) emissions, known as a major cause of climate change, have been emitted by the combustion of fossil fuels over the past few decades. The transportation sector contributes significantly to global GHG emissions. Inspired by the successful implementation of tradable credit schemes (TCSs) in pollution control programs, this dissertation focuses on multi-period TCSs to minimize vehicular emissions. In this scheme, a central authority (CA) allocates travel credits to travelers (credit allocation scheme) and then, charges them to travel on each link (credit charging scheme). Travelers are able to trade credits amongst themselves in the market. To address the …

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Folate Receptor Beta As A Marker Of Immunosuppressive Myeloid Derived Suppressor Cells And Tumor Associated Macrophages In The Tumor Microenvironment, Gregory Micheal Cresswell May 2018

Folate Receptor Beta As A Marker Of Immunosuppressive Myeloid Derived Suppressor Cells And Tumor Associated Macrophages In The Tumor Microenvironment, Gregory Micheal Cresswell

Open Access Dissertations

Immunosuppression within a tumor environment is a key component of the development and ultimately spread of cancer in the body. Myeloid Derived Suppressor Cells (MDSC) and Tumor Associated Macrophages (TAMs) are two of the primary forces behind immunosuppression within the tumor environment. MDSC are a functionally defined group of myeloid cells that have the capacity to suppress anti-tumor T cell responses, induce regulatory T cells (Tregs), polarize inflammatory macrophages to TAMs, and promote metastasis. This broad ability to control the immune response has led to a great deal of focus on the function of these cells. However, despite efforts to …

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Polymer-Based Piezoelectric Material And Device For Energy Harvesting/Health Monitoring In Civil Infrastructure, Eshan Ghafari May 2018

Polymer-Based Piezoelectric Material And Device For Energy Harvesting/Health Monitoring In Civil Infrastructure, Eshan Ghafari

Open Access Dissertations

Recent studies on piezoelectric materials have resulted in the development of a wide verity of piezoelectric devices such as nanogenerators and sensors. This technology is prevalently dominated by the ceramic materials which are brittle and have a very limited strain level. Moreover, despite a wide working frequency range, the ceramic-based piezoelectric devices can only work under tiny forces to avoid damage to the device. As such, due to inherent brittleness, the piezoelectric technology has not been widely explored in civil engineering applications due to the aforementioned drawbacks of ceramic materials. This thesis aims to develop an efficient piezoelectric polyvinylidene fluoride …

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Mass Spectrometric Studies On A Functional Group-Selective Ion-Molecule Reaction And The Reactivity Of Bi And Polyradicals, Joann P. Max May 2018

Mass Spectrometric Studies On A Functional Group-Selective Ion-Molecule Reaction And The Reactivity Of Bi And Polyradicals, Joann P. Max

Open Access Dissertations

Mass spectrometry (MS) is a versatile analytical tool for the characterization of unknown compounds in complex mixtures. MS separates the ionized components of a mixture based on their m/z values and provides accurate molecular weight information and elemental compositions for the ionized analytes. Tandem mass spectrometry (MS/MS) based on collision-activated dissociation or ion-molecule reactions can be used for structural characterization of the ionized analytes. MS/MS can also be used to probe the intrinsic properties of highly reactive intermediates that are difficult to study in solution. The experiments described in this thesis focus on the examination of various gas-phase reactions. A …

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High School Redesign And The Senior Year, Park D. Ginder May 2018

High School Redesign And The Senior Year, Park D. Ginder

Open Access Dissertations

The purpose of this qualitative study was to describe how high school principals in Indiana are redesigning senior year academic experiences as a means to increasing student engagement and making the senior year more valuable for students. Using an exploratory multiple-case study design, three high school principals serving in high performing high schools in Indiana (as defined by the Indiana Department of Education rating each school an “A”) were interviewed, with interviews recorded and transcribed, then coded for item analysis. The participants’ commentary, outlined themes, and sub-themes from the case study provide insight into the experiences of high school principals …

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