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Instrumentation And Development Of A Mass Spectrometry System For The Study Of Gas-Phase Biomolecular Ion Reactions, Ziqing Lin Jan 2015

Instrumentation And Development Of A Mass Spectrometry System For The Study Of Gas-Phase Biomolecular Ion Reactions, Ziqing Lin

Open Access Dissertations

Gas-phase reactions of biomolecular ions are highly relevant to the understanding of structures and functions of the biomolecules. Mass spectrometry is a powerful tool in investigating gas-phase ion chemistry. Various mass spectrometers have been developed to explore ion/molecule reactions, ion/ion reactions, ion/photon reactions, ion/radical reactions etc., both at atmospheric pressure and in vacuum. In-vacuum reactions have an advantage of involving pre-selecting the ions for the reactions using a mass analyzer. Over the decades, a variety of mass analyzers have been employed in the research of ion chemistry. Hybrid configurations, such as quadrupole ion trap with a time-of-flight and or a …

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Modeling, Optimization, And Sensitivity Analysis Of A Continuous Multi-Segment Crystallizer For Production Of Active Pharmaceutical Ingredients, Bradley James Ridder Jan 2015

Modeling, Optimization, And Sensitivity Analysis Of A Continuous Multi-Segment Crystallizer For Production Of Active Pharmaceutical Ingredients, Bradley James Ridder

Open Access Dissertations

We have investigated the simulation-based, steady-state optimization of a new type of crystallizer for the production of pharmaceuticals. The multi-segment, multi-addition plug-flow crystallizer (MSMA-PFC) offers better control over supersaturation in one dimension compared to a batch or stirred-tank crystallizer. Through use of a population balance framework, we have written the governing model equations of population balance and mass balance on the crystallizer segments. The solution of these equations was accomplished through either the method of moments or the finite volume method. The goal was to optimize the performance of the crystallizer with respect to certain quantities, such as maximizing the …

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Synthetic Steganography: Methods For Generating And Detecting Covert Channels In Generated Media, Philip Carson Ritchey Jan 2015

Synthetic Steganography: Methods For Generating And Detecting Covert Channels In Generated Media, Philip Carson Ritchey

Open Access Dissertations

Issues of privacy in communication are becoming increasingly important. For many people and businesses, the use of strong cryptographic protocols is sufficient to protect their communications. However, the overt use of strong cryptography may be prohibited or individual entities may be prohibited from communicating directly. In these cases, a secure alternative to the overt use of strong cryptography is required. One promising alternative is to hide the use of cryptography by transforming ciphertext into innocuous-seeming messages to be transmitted in the clear. ^ In this dissertation, we consider the problem of synthetic steganography: generating and detecting covert channels in generated …

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Structure-Activity Relationships For The Water-Gas Shift Reaction Over Supported Metal Catalysts, Kaiwalya D. Sabnis Jan 2015

Structure-Activity Relationships For The Water-Gas Shift Reaction Over Supported Metal Catalysts, Kaiwalya D. Sabnis

Open Access Dissertations

The Water-Gas Shift (WGS) reaction (CO + H2O → CO2 + H2) is an important chemical process for industrial hydrogen production. The overall goal of this project is to use kinetic experiments and in situ characterization techniques in tandem, in order to derive structure-activity relationships for various catalytic systems. These relationships facilitate the rational catalyst design by identification of catalyst descriptors. In order to establish such relationships, various studies were undertaken, such as (i) effect of transition admetals on the WGS catalysis by molybdenum carbide (ii) effect of residual oxygen content on the performance of …

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Measurement Of The Drell--Yan Differential Cross Section With The Cms Detector At The Lhc, Alexey Svyatkovskiy Jan 2015

Measurement Of The Drell--Yan Differential Cross Section With The Cms Detector At The Lhc, Alexey Svyatkovskiy

Open Access Dissertations

This thesis describes precision measurements of electroweak interactions in a new energy regime and the application of these measurements to improve our understanding of the structure of the proton. The results are based on proton-proton collision data at √s = 7 and 8\TeV recorded with the Compact Muon Solenoid detector at the CERN Large Hadron Collider during the first years of operation. Measurements of the differential Drell–Yan cross section in the dimuon and dielectron channels covering the dilepton mass range of 15 to 2000\GeV and absolute dilepton rapidity from 0 to~2.4 are presented. The Drell–Yan cross section in proton-proton …

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Mach: A Model For Explaining Molecular And Cellular Mechanisms, Caleb M. Trujillo Jan 2015

Mach: A Model For Explaining Molecular And Cellular Mechanisms, Caleb M. Trujillo

Open Access Dissertations

Biologists use mechanistic explanations to understand behaviors of the immense complexity of molecular and cellular systems. In undergraduate biology courses, students are expected to explain molecular and cellular mechanisms, but teaching this skill presents many challenges due to the highly abstract, intangible nature of the cellular world, the influence of everyday language, and the tendency of students to overestimate how much they can explain. Therefore, across three studies this dissertation addresses these obstacles to teach undergraduate biology students to explain molecular and cellular mechanisms. ^ The first step was to model how biology experts explain molecular and cellular mechanisms, and …

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A 2-Categorical Extension Of The Reshetikhin--Turaev Theory, Yu Tsumara Jan 2015

A 2-Categorical Extension Of The Reshetikhin--Turaev Theory, Yu Tsumara

Open Access Dissertations

We concretely construct a 2-categorically extended topological quantum field theory that extends the Reshetikhin-Turaev TQFT to cobordisms with corners. The source category will be a well chosen 2-category of decorated cobordisms with corners and the target bicategory will be the Kapranov-Voevodsky 2-vector spaces.

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Novel Techniques For Quasi Three-Dimensional Nanofabrication Of Transformation Optics Devices, Paul R. West Jan 2015

Novel Techniques For Quasi Three-Dimensional Nanofabrication Of Transformation Optics Devices, Paul R. West

Open Access Dissertations

Current nanofabrication is almost exclusively limited to top-down, two-dimensional techniques. As technology moves more deeply into the nano-scale regime, fabrication of new devices with quasi three-dimensional geometries shows great potential. One excellent example of an emerging field that requires this type of non-conformal 3D fabrication technique is the field of Transformation Optics. This field involves transforming and manipulating the optical space through which light propagates. Arbitrarily manipulating the optical space requires advanced fabrication techniques, which are not possible with current two-dimensional fabrication technologies. One step toward quasi three-dimensional nanofabrication involves employing angled deposition allowing new growth mechanisms, and enabling a …

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Structure-Thermal Coupling In Viscoelastic Material In Rubber Bushing Of Vehicle System, Zhengui Zhang Jan 2015

Structure-Thermal Coupling In Viscoelastic Material In Rubber Bushing Of Vehicle System, Zhengui Zhang

Open Access Dissertations

The objective of this research is to utilize the frequency-dependent viscoelastic material model and characterize the dynamic response of rubber bushing under external excitation. Furthermore, with appropriate modeling, two heat generation mechanisms of rubber bushing are explored and their thermal fields are investigated. Due to the nonlinear force-deflection relationship of the viscoelastic material, finding satisfactory mechanical properties of rubber components still poses a great challenge. However, industry nowadays is in urgent demand for precise finite element analysis (FEA) modeling of rubber components. For example, a proper constitutive relationship of rubber components is critical to providing a reliable and trustable simulation …

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Laser Scanner Jitter Characterization, Page Content Analysis For Optimal Rendering, And Understanding Image Graininess, Yi-Ting Chen Jan 2015

Laser Scanner Jitter Characterization, Page Content Analysis For Optimal Rendering, And Understanding Image Graininess, Yi-Ting Chen

Open Access Dissertations

In Chapter 1, the electrophotographic (EP) process is widely used in imaging systems such as laser printers and office copiers. In the EP process, laser scanner jitter is a common artifact that mainly appears along the scan direction due to the condition of polygon facets. Prior studies have not focused on the periodic characteristic of laser scanner jitter in terms of the modeling and analysis. This chapter addresses the periodic characteristic of laser scanner jitter in the mathematical model. In the Fourier domain, we derive an analytic expression for laser scanner jitter in general, and extend the expression assuming a …

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Advanced Wireless Communications Using Large Numbers Of Transmit Antennas And Receive Nodes, Junil Choi Jan 2015

Advanced Wireless Communications Using Large Numbers Of Transmit Antennas And Receive Nodes, Junil Choi

Open Access Dissertations

The concept of deploying a large number of antennas at the base station, often called massive multiple-input multiple-output (MIMO), has drawn considerable interest because of its potential ability to revolutionize current wireless communication systems. Most literature on massive MIMO systems assumes time division duplexing (TDD), although frequency division duplexing (FDD) dominates current cellular systems. Due to the large number of transmit antennas at the base station, currently standardized approaches would require a large percentage of the precious downlink and uplink resources in FDD massive MIMO be used for training signal transmissions and channel state information (CSI) feedback. First, we propose …

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Overweight Vehicle Permitting Alternatives, Stephanie R Everett Jan 2015

Overweight Vehicle Permitting Alternatives, Stephanie R Everett

Open Access Dissertations

Overweight vehicles exceed the federal and/or state statutory limits for either the gross vehicle weight (GVW) or the weight of individual axles or axle groups. National and state limits on vehicle weights were established to preserve the highway infrastructure. Past research has shown that overweight operations, while causing significant damage to roads and bridges, can enhance the trucking industry productivity, and thus yield economic benefits both regionally and nationally. In the United States, individual states administer oversize and overweight vehicle permit programs to regulate and collect revenues from overweight operations. Differences in the truck size and weight limits and overweight …

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Non-Fouling Affinity Platforms For Protein Immobilization In Electron Microscopy, Christopher Jerome Benjamin Jan 2015

Non-Fouling Affinity Platforms For Protein Immobilization In Electron Microscopy, Christopher Jerome Benjamin

Open Access Dissertations

Single-particle reconstruction has grown significantly with the improvements in various data collection and computational strategies including CTF fitting, the use of vitrified samples and the utilization of ultra-sensitive direct electron detectors. Although these improvements have contributed significantly to the recent evolution of 3D reconstruction analysis, the way samples are prepared for electron microscopy has remained largely unchanged. We report the development of TEM grids that are modified with non-fouling coatings bearing surface grafted nitrilotriacetic acid substituents that promotes specific capture of protein targets for high resolution TEM analysis. The utilization of these grids for specific adsorption of the targeted protein …

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Development Of A Multi-Body Nonlinear Model For A Seat-Occupant System, Yousof Azizi Jan 2015

Development Of A Multi-Body Nonlinear Model For A Seat-Occupant System, Yousof Azizi

Open Access Dissertations

A car seat is an important component of today's cars, which directly affects ride comfort experienced by occupants. Currently, the process of ride comfort evaluation is subjective. Alternatively, the ride comfort can be evaluated by a series of objective metrics in the dynamic response of the occupant. From previous studies it is well known that the dynamic behavior of a seat-occupant system is greatly affected by soft nonlinear viscoelastic materials used in the seat cushion. Therefore, in this research, especial attention was given to efficiently modeling the behavior of seat cushion. In the first part of this research, a phenomenological …

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Optimizing Integrated Airport Surface And Terminal Airspace Operations Under Uncertainty, Christabelle Simone Juliette Bosson Jan 2015

Optimizing Integrated Airport Surface And Terminal Airspace Operations Under Uncertainty, Christabelle Simone Juliette Bosson

Open Access Dissertations

In airports and surrounding terminal airspaces, the integration of surface, arrival and departure scheduling and routing have the potential to improve the operations efficiency. Moreover, because both the airport surface and the terminal airspace are often altered by random perturbations, the consideration of uncertainty in flight schedules is crucial to improve the design of robust flight schedules. Previous research mainly focused on independently solving arrival scheduling problems, departure scheduling problems and surface management scheduling problems and most of the developed models are deterministic.

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Granulation Of Ultra-Fine Powders: Examination Of Granule Microstructure, Consolidation Behavior, And Powder Feeding, Nathan Bellemore Davis Jan 2015

Granulation Of Ultra-Fine Powders: Examination Of Granule Microstructure, Consolidation Behavior, And Powder Feeding, Nathan Bellemore Davis

Open Access Dissertations

Davis, Nathan B. Ph.D., Purdue University, December 2015. Granulation Behavior of Ultra-Fine Powders: Examination of Granule Microstructure, Consolidation Behavior, and Powder Feeding. Major Professor: James Litster

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Signal Enhancement And Data Mining For Biological And Chemical Samples Using Mass Spectrometry, Yuezhi Du Jan 2015

Signal Enhancement And Data Mining For Biological And Chemical Samples Using Mass Spectrometry, Yuezhi Du

Open Access Dissertations

Mass spectrometry has been actively involved in the areas of healthcare, pharmaceutics, environmental analysis, food industry and forensics due to its ability to provide molecular information at trace levels. Recently, because of the complexity of chemical and biological samples, computer-assisted mass spectra analysis, including signal enhancement, statistics and machine learning, has been drawn more and more attention especially for researches in biomarker identification, sample classification and omics-related areas where high volume of data is generated.

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Detailed Investigations Of Capillary And Van Der Waals Forces In The Adhesion Between Solids, Aaron Harrison Jan 2015

Detailed Investigations Of Capillary And Van Der Waals Forces In The Adhesion Between Solids, Aaron Harrison

Open Access Dissertations

The primary focus of this dissertation is on characterizing two fundamental forces common to adhesion between solids: capillary and van der Waals forces. These two forces have a significant impact on how solids flow, stick to surfaces, agglomerate and break; therefore, understanding their behavior can lead to better processing techniques.

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Multiphase Reaction Studies In Stirred Tank And Fixed Bed Reactors, Shinbeom Lee Jan 2015

Multiphase Reaction Studies In Stirred Tank And Fixed Bed Reactors, Shinbeom Lee

Open Access Dissertations

A biphasic stirred tank reactor and a trickle bed reactor were studied to understand complex multiphase reactor behavior arising from mass transfer effects on reactions and to improve modeling accuracy for rational design and optimization.

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Dissolution Behavior Of Amorphous Solid Dispersions, Matthew James Jackson Jan 2015

Dissolution Behavior Of Amorphous Solid Dispersions, Matthew James Jackson

Open Access Dissertations

Current drug discovery techniques tend to identify potential new drug entities with more complex structures which may pose significant formulation challenges. In particular, an increasingly large number of new drug compounds have extremely poor solubility in water, impacting the bioavailability of the drug. Solubility enhancement techniques, such as amorphous solid dispersions (ASDs), can be used in oral dosage forms to increase the apparent solubility of the drug in the gastrointestinal tract thus increasing the bioavailability of the drug. However, the drug solution generated from the dissolution of an ASD formulation is supersaturated. In other words, the solution concentration is higher …

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High-Fidelity Gravity Modeling Applied To Spacecraft Trajectories And Lunar Interior Analysis, Loic Chappaz Jan 2015

High-Fidelity Gravity Modeling Applied To Spacecraft Trajectories And Lunar Interior Analysis, Loic Chappaz

Open Access Dissertations

As the complexity and boldness of emerging mission proposals increase, and with the rapid evolution of the available computational capabilities, high-accuracy and high-resolution gravity models and the tools to exploit such models are increasingly attractive within the context of spaceflight mechanics, mission design and analysis, and planetary science in general. First, in trajectory design applications, a gravity representation for the bodies of interest is, in general, assumed and exploited to determine the motion of a spacecraft in any given system. The focus is the exploration of trajectories in the vicinity of a system comprised of two small irregular bodies. Within …

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Incorporating A Small-Group Affective Curriculum Model Into A Diverse, Summer Program For Talented Youth: A Design Based Research Study, Enyi Jen Jan 2015

Incorporating A Small-Group Affective Curriculum Model Into A Diverse, Summer Program For Talented Youth: A Design Based Research Study, Enyi Jen

Open Access Dissertations

In this study, I used Design-Based Research (DBR), as a methodological framework, to guide the development and implementation of the GERI Affective Model into a diverse, university-based, summer enrichment residential program for talented youth. The purposes of this study were to build an evidence-based affective intervention, to explore how participation in the affective curriculum influenced high-ability students' social and emotional development and to use the results to refine the GERI Affective Model before dissemination. This research included two phases, an initial design phase in 2012 to 2013 and an outcome study in 2014. In the initial design phase, I designed …

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Second Language Writing Instructor Written Feedback Practices In An Esl Freshman Composition Class: A Complexity Theory Perspective, Masakazu Mishima Jan 2015

Second Language Writing Instructor Written Feedback Practices In An Esl Freshman Composition Class: A Complexity Theory Perspective, Masakazu Mishima

Open Access Dissertations

This case study investigated second language writing instructors’ written feedback practices from a complexity theory perspective. The purpose of the research was to explore and examine contextual factors and their impact on instructor written feedback practices. Data were collected from two ESL writing instructors and two ESL writers through surveys, interviews, and classroom observations. Based on the results, a complexity theory-based model of second language writing instructor written feedback practices was developed to represent the complexity of written feedback practice situated in the specific instructional context. The findings suggest that the instructors were under constant influence of five different contextual …

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The Depth And Complexity Program Evaluation Tool: A New Method For Conducting Internal Evaluations Of Gifted Education Programs, Jason Scott Mcintosh Jan 2015

The Depth And Complexity Program Evaluation Tool: A New Method For Conducting Internal Evaluations Of Gifted Education Programs, Jason Scott Mcintosh

Open Access Dissertations

Few program evaluation models unique to gifted education currently exist. The Depth and Complexity Program Evaluation Tool (DC-PET) is a new method for conducting an evaluation of a gifted program that combines the Kaplan Depth and Complexity Model with tools and techniques from the fields of program evaluation and organizational change. The tool was designed to assist local school district personnel in generating data for gifted program improvement by requiring a close examination of critical issues in the field (e.g., defensible differentiation, underserved populations, twice-exceptional learners). The DC-PET is meant to provide a framework for guiding those who have little …

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Analysis Of A Rotating Spool Expander For Organic Rankine Cycle Applications, Abhinav Krishna Jan 2015

Analysis Of A Rotating Spool Expander For Organic Rankine Cycle Applications, Abhinav Krishna

Open Access Dissertations

Increasing interest in recovering or utilizing low-grade heat for power generation

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Manganese Toxicity: Accumulation In Bone, Effect On Brain Neurochemistry, And Impact On Adult Neurogenesis, Stefanie O'Neal Jan 2015

Manganese Toxicity: Accumulation In Bone, Effect On Brain Neurochemistry, And Impact On Adult Neurogenesis, Stefanie O'Neal

Open Access Dissertations

O’Neal, Stefanie L. Ph.D., Purdue University, December 2015. Manganese Toxicity: Accumulation in Bone, Effect on Neurochemistry, Impact on Adult Neurogenesis. Major Professor: Wei Zheng.

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A Comparison Of Two Instructional Sequences In An Intelligent Tutoring Program On Multiplicative Concepts And Problem Solving Of Students With Mathematics Difficulties, Joo Young Park Jan 2015

A Comparison Of Two Instructional Sequences In An Intelligent Tutoring Program On Multiplicative Concepts And Problem Solving Of Students With Mathematics Difficulties, Joo Young Park

Open Access Dissertations

One of the crucial goals of the National Councils of Teachers Mathematics standards (2000) was to have all students, including students with mathematics difficulties (MD), to succeed in establishing a higher-order thinking in mathematic.

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Photonic Metasurfaces For Spatiotemporal And Ultrafast Light Control, Amr Shaltout Jan 2015

Photonic Metasurfaces For Spatiotemporal And Ultrafast Light Control, Amr Shaltout

Open Access Dissertations

The emergence of photonic metasurfaces - planar arrays of nano-antennas - has enabled a new paradigm of light control through wave-front engineering. Space-gradient metasurfaces induce spatially varying phase and/or polarization to propagating light. As a consequence, photons propagating through space-gradient metasurfaces can be engineered to undergo a change to their momentum, angular momentum and/or spin states.

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Impact Of Polymers On The Solution Crystal Growth Rate Of A Poorly Water-Soluble Active Pharmaceutical Ingredient, Caitlin J. Schram Jan 2015

Impact Of Polymers On The Solution Crystal Growth Rate Of A Poorly Water-Soluble Active Pharmaceutical Ingredient, Caitlin J. Schram

Open Access Dissertations

Poor aqueous solubility is a major impediment to the oral delivery of over 75% of pharmaceutical compounds currently under development. The bioavailability of these compounds can be enhanced with the use of supersaturating dosage forms, due to their high flux rates across the gastrointestinal tract membrane. However, the success of this strategy hinges on the ability to inhibit crystallization of the supersaturated drug solutions. Polymers can be used to inhibit crystallization and prolong supersaturation, however the mechanisms of polymer inhibition are not yet fully understood. Therefore it is desirable to understand the attributes that render a polymer effective. In this …

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Mental Health And Human Minds: Some Theoretical Criteria For Clinical Psychiatry, Natalia Washington Jan 2015

Mental Health And Human Minds: Some Theoretical Criteria For Clinical Psychiatry, Natalia Washington

Open Access Dissertations

When it comes to the topic of mental illness, there are three broad areas of concern that are of interest to all of us as human beings—and to the theorists, researchers, and clinicians who wish to offer help—besides knowing what our symptoms are. First, we might be interested in finding out some normative facts about ourselves as individuals, such as whether or not we are mentally healthy, perhaps to what extent, and how this should affect our motivations. A second area of concern involves descriptive facts our minds. In what ways do we deviate from typical human psychological nature, and …

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