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Abstract: Fibre reinforcement in concrete mitigates cracking, significantly enhancing peak, post-cracking, and toughness responses. The versatile applications of Fibre-reinforced Concrete (FRC) encompass parking lots, taxiways, runways, ground slabs, tunnels, barriers, railway tracks, site access road bridges, and culverts, showcasing its adaptability across diverse infrastructure projects, from transportation networks to structural foundations. A profound understanding of FRC's compressive and flexural behaviour holds paramount importance in designing structural elements such as beams, slabs, columns, piers, and compressive struts of beams. Commonly, Steel fibres (SFs) and glass fibres (GF) are often added to concrete to enhance toughness, durability, and post-cracking response, affecting the flexural and cracking behaviour of Fiber Reinforced Concrete (FRC). Understanding this is important because fibres increase moment resistance and stiffness. The investigation initiates with the optimization of mixture designs for FRC, examining the impact of fibre type (SF, GF, and/or a combination to evaluate the benefits of non-corrosive and deformable GF with higher stiffness SF), aspect ratios (55 for SF and 67 for GF), lengths (50 mm for SF and 36 mm for GF) and dosage (0.5, 1.0, and 1.5% by volume fraction). The findings reveal substantial reductions in slump with increased fibre content, offering nuanced insights crucial for concrete mixture designers and structural engineers. Moving to the compressive behaviour of FRC, the study examines the effects of incorporating SF and/or GF on critical parameters such as compressive strength, modulus of elasticity, Poisson’s ratio, and toughness index. A simplified model is proposed to understand how adding fibres changes the stress-strain relationship in concrete. Subsequently, the research delves into the flexural and cracking behaviour of FRC prisms, employing a combination of experimental and analytical methods. The outcomes introduce proposed design-oriented expressions for equivalent stress block parameters, refining our understanding of FRC's structural response. Addressing a notable gap in the literature, the thesis employs Finite Element Analysis (FEA) to model large-scale Steel Reinforced (SR)-FRC and Glass Fibre-Reinforced Polymer (GFRP)-FRC beams. This analysis extends beyond conventional load-displacement considerations to encompass parameters like crack width and reinforcement strain. The findings show the viability of FEA predictions for both steel and GFRP reinforced concrete beams response, indicating a potentially cost-effective alternative to extensive experimental programs. The recent update in one-way shear provisions for steel-reinforced concrete by the American Concrete Institute prompts consideration for similar provisions in Fibre-Reinforced Polymer (FRP) Reinforced Concrete (FRP-RC). The lower shear strength of FRP-RC, particularly GFRP, is attributed to its considerably lower modulus of elasticity compared to steel. This research evaluates existing design provisions for one-way shear in FRP-reinforced concrete, offering recommendations based on an analysis of 147 tests documented in the literature. The CSA S806-12 standard is considered the most consistent at predicting shear strength. Lastly, this study used the numerical database from FEA to develop service and ultimate design equations for FRC with SR and GFRP bars. The flexural and shear strength models demonstrated precision. Short-term deflection and reinforcement strain were obtained by deriving an effective moment of inertia for FRC. The FEA underestimates deflection because it often assumes ideal and perfect conditions. The analytical model accurately predicts reinforcement strain, aligning closely with FEA results. These findings significantly advance our understanding of FRC structures, guiding future research and practical applications in structural engineering. The investigation initiates with the optimization of mixture designs for FRC, examining the impact of fibre type (SF, GF, and/or a combination to evaluate the benefits of non-corrosive and deformable GF with higher stiffness SF), aspect ratios (55 for SF and 67 for GF), lengths (50 mm for SF and 36 mm for GF) and dosage (0.5, 1.0, and 1.5% by volume fraction). The findings reveal a reduction in slump with increased fibre content, offering nuanced insights crucial for concrete mixture designers and structural engineers. Moving to the compressive behaviour of FRC, the study examines the effects of incorporating SF and/or GF on critical parameters such as compressive strength, modulus of elasticity, Poisson’s ratio, and toughness index. A simplified model is proposed to understand how adding fibres changes the stress-strain relationship in concrete. Subsequently, the research delves into the flexural and cracking behaviour of FRC prisms, employing a combination of experimental and analytical methods. The outcomes introduce proposed design-oriented expressions for equivalent stress block parameters, refining our understanding of FRC's structural response. The thesis employs Finite Element Analysis (FEA) to model large-scale Steel Reinforced (SR)-FRC and Glass Fibre-Reinforced Polymer (GFRP)-FRC beams. This analysis extends beyond conventional load-displacement considerations to encompass parameters like crack width and reinforcement strain. The findings show the viability of FEA predictions for both steel and GFRP reinforced concrete beams response, indicating a potentially cost-effective alternative to extensive experimental programs. The recent update in one-way shear provisions for steel-reinforced concrete by the American Concrete Institute prompts consideration for similar provisions in Fibre-Reinforced Polymer (FRP) Reinforced Concrete (FRP-RC). This research evaluates existing design provisions for one-way shear in FRP-reinforced concrete, offering recommendations based on an analysis of 147 tests documented in the literature. The CSA S806-12 standard is considered the most consistent at predicting shear strength. Lastly, this study used the numerical database from FEA to develop service and ultimate design equations for FRC with SR and GFRP bars. The flexural and shear strength models demonstrated precision. Short-term deflection and reinforcement strain were obtained by deriving an effective moment of inertia for FRC. The FEA underestimates deflection because it often assumes ideal and perfect conditions. The analytical model accurately predicts reinforcement strain, aligning closely with FEA results. These findings significantly advance our understanding of FRC structures, guiding future research and practical applications in structural engineering.

In order to remain competitive in the marketplace, all motor vehicle manufacturers face difficult decisions with regard to balancing cost vs. feature. That is to say that the manufacturer must balance the cost of the product to the customer to remain competitive whilst offering appropriate technology and standard features required by that customer. All motor manufacturers are therefore under pressure to keep costs of nonfeature items to a minimum. One of the cost reductions items prevalent on most vehicles is the deletion of the structural member that attaches the rear bumper, known as the bumper beam (RBB), which is researched in this Thesis. This generates average vehicle savings of $20 and, as this is invisible to the customer, should enable the manufacturers to realise a significant saving or allow this revenue to be spent on additional feature without loss of vehicle function. However, in nearly all cases, deletion of the rear bumper beam has the effect of degrading the steering responses of the vehicle by 1 to 1½ rating points (out of 10), which is contrary to the premise of cost reductions; which is to ensure that vehicle function is unaffected. Initial analysis of vehicles with deleted rear bumper beams cannot show an objective measurable difference in any vehicle behaviours with or without the beam fitted, and hence CAE studies using ADAMS models cannot verify the effects of the bumper beam. It was necessary to employ unconventional modelling and testing methods such as rigid body, flexible body model techniques as well as experimental studies included driving robots and expert driver appraisals. The research demonstrated that vehicle modelling methods currently used, cannot establish or predict the complete vehicle ride and handling status. A total vehicle model approach should be used without separating the body CAE model and vehicle dynamics ADAMS model into separate entities. Furthermore, it was concluded that the determination to the effects of body hysteresis rather than pure stiffness is of crucial importance and that the steering attribute could be maintained with the deletion of the RBB analytically.

The accurate evaluation of interlaminar stresses is of great significance in the analysis and design of laminated and piezoelectric laminated structures because complex behaviours of these stresses near free edges initiate edge delamination that raises concerns about the structural integrity and reliability. This thesis presented 3D hybrid analyses on the interlaminar stresses to investigate the electromechanical coupling and free edge effects of piezoelectric laminated plates with an emphasis on the realistic distributions of the 3D stress and electric fields near free edges. In this research, the state space equations for simply-supported and free-edge piezoelectric laminates under transverse loads and infinite long free-edge piezoelectric laminates under uniaxial extension were obtained in the framework of 3D piezoelasticity by considering all the independent elastic and piezoelectric constants. The equations satisfy the traction-free and open-circuit boundary conditions at free edges and the continuity conditions across all interfaces. On the basis of the transfer matrix and recursive solution approaches, 3D exact solutions were sought by a novel non-uniform layer refinement technique to evaluate the accuracy of the finite element method (FEM), and realistic gradients of interlaminar stresses and electric fields were captured. The FEM results were in good agreement with those from the present solutions except for the regions near free edges. For simply-supported and free-edge laminates, stress variations with material properties, geometries and stacking sequences were obtained. The interlaminar stress τxz was dominant at corners and τyz also tended to contribute to delamination. In the infinite long free-edge laminates, σz, τyz, Ey and Ez exhibited significant gradients near free edges. Furthermore, the considerable influence of the electromechanical coupling effect on interlaminar stresses revealed that piezoelectric laminates were more susceptible to edge delamination and the application of closed-circuited surface conditions might prevent such edge delamination. The present analytical solution demonstrated an improvement in precision over other 2D analytical and numerical solutions and could serve as a benchmark for the determination of interlaminar stresses and electric fields near the free edges of the piezoelectric laminates.

High-throughput screening (HTS) of asymmetric transformations is vital to the development of modern pharmaceuticals and fine chemicals. Enantiomeric excess (ee) determination of asymmetric transformations is accelerated through the use optical techniques such as circular dichroism (CD)-based ee determination assays. However, the implementation of these assays requires calibration experiments using enantioenriched materials, which ultimately hinder the use of these assays in real-world applications. We report the prediction of calibration curves used in ee determination assays for chiral amines using a data-driven approach. By leveraging density functional theory-based chemical descriptors, we have developed a model that predicts calibration curves without performing prior calibration experiments. This calibration curve prediction method was applied to a multicomponent ortho-iminoboronic acid assembly. The ee values measured with the predicted calibration curves were within 10% of those measured with the experimental calibration curves. The generality of this approach was demonstrated using an octahedral Fe(II) complex for the ee determination of chiral amines. A diverse library of analytes was created to elucidate the electronic and steric factors which influence the CD response of the Fe(II) complex. After assessing the scope and limitations of the assay, we generated a model of calibration curves which could be used to determine the ee of unknown solutions with less than 6% error. This computational approach circumvents the need for chiral resolution to perform calibration experiments, which will ultimately accelerate reaction discovery and optimization.

Utilizing the unique and varied properties of metals, such as their redox activity, lability, and net charge, metal-based prodrugs can be designed and optimized for numerous applications. The most prominent usage of metal-based prodrugs has historically been anti-cancer agents, though there have been more recent efforts in the development of theranostic and antimicrobial agents as well. Gallium has promise for extending the scope of metal-based prodrugs, as it has been FDA approved for the treatment of tumors and hypercalcemia. Epinephrine is a compelling target for a gallium-based prodrug as conventional prodrugs are not suitable for the treatment of anaphylactic shock. This is because the prodrugs are inactive during their long half-lives. Additionally, as should mitigate drug degradation from high pH, light, and heat. The development of a novel gallium prodrug of epinephrine establishes the first prodrug treatment of anaphylactic shock, and extends the chemical space of metal-based prodrugs.

Illicitly manufactured fentanyls (IMFs) have become a global and local epidemic and have recently caused an increase in the number of accidental exposures and overdoses in first responders and the community. The aim of the research is to explore a method to discriminate between IMFs and cutting agents in mock street samples using Raman Spectroscopy. Predominant Raman bands corresponding to the structural moieties of each individual illicit, licit drugs, and cutting agents were tracked, then used to discriminate between varying components in a mock street sample. In conclusion, discrimination between the components in the mixture was obtained using Raman Spectroscopy. The inquiry will provide the basis for a viable method in the prevention of accidental exposures and overdoses in first responders and the general public.

Portable mass spectrometry has become an important analytical tool for chemical detection and identification outside of a lab setting. Many variations and applications have been developed to benefit various fields of science. Membrane inlet mass spectrometry is used to allow certain analytes to pass into the mass spectrometer without breaking vacuum or letting in large particulate matter. These two important analytical tools have been applied to the detection of harmful chemicals in the air. Earth-based separations and reverse gas stack modelling are useful mathematical tools that can be used to locate the source of a chemical release by back calculation. Earth-based separations studies the way different molecules will diffuse and separate through the air. Reverse gas stack modelling refers to the concentration differences of a chemical in relation to its distance from its source. These four analytical techniques can be combined to quickly and accurately locate various harmful chemical releases. The same system can be used for many applications and has been tested to detect harmful chemicals within and air-handling system. The monitoring of air-handling systems can greatly reduce the threat of harm to the building occupants by detecting hazardous chemicals and shutting off the air flow to minimize human exposure.

Anthocyanins (ACYs) are polyphenol compounds found in nature, which contribute vivid colors to many fruits and vegetables, while also possessing significant health benefits. These pigments range in color from orange-red to blue-violet and could serve as natural colorants to replace artificial additives. There is a great demand from consumers to have fewer artificial compounds in their foods. However, the relatively instability of ACYs must be further understood in order to limit color degradation before they can completely replace synthetic colorants. ACYs slowly degrade over time, but there is a knowledge gap on their fate and mechanisms causing degradation. In order to understand the mechanistic changes, different techniques were employed to understand ACY transformations over storage. Various types of solid phase extraction, high-pressure liquid chromatography columns, and gel electrophoresis analyses were used in an attempt to separate anthocyanin-tannin polymers by degree of polymerization. These compounds were detected using mass spectrometry, but separation by chromatographic techniques was not possible. Ascorbic acid accelerates ACY degradation, but the mechanism was controversial. Model systems of a pure ACY, cyanidin-3-glucoside (C3G), and blackberry juice supplemented with ascorbic acid were prepared and hydroxyl radicals formed via the Haber-Weiss reaction. Hydroxyl radicals are highly unstable and reacted with C3G forming 6-hydroxy-C3G, which degrades faster than C3G. The combination of identifying the hydroxylated ACY using tandem mass spectrometry and detection the hydroxyl radicals via electron spin resonance verified the reaction mechanism of ascorbic acid catalyzed degradation of ACYs. Next, blackberry juice was supplemented with various additives to understand ACY stabilization mechanisms. Glutathione significantly improved anthocyanin retention over storage, so combinations of glutathione with lipoic and ascorbic acids were added to assess a potential antioxidant recycling mechanism. The combination was not more effective at stabilizing ACYs than glutathione alone. Finally, novel ACY compounds were created from radishes through a reaction originally found in wine fermentation. Using acetaldehyde as a polymerization agent, radish ACYs reacted with catechin to form stable pigments that were identified by mass spectrometry. This research furthers the understanding of anthocyanin reactions and degradation mechanisms, which improves their use as natural colorants in the food and beverage industry.

Terahertz spectroscopy has found use as an analytical tool in determining chemical composition of exhaled human breath. This thesis demonstrates a novel application of this technology - analytical sensing of gaseous metabolic products of several types of human cell cultures. An innovative experimental system was developed for probing cellular metabolism using terahertz [THz] rotational spectroscopy. Gaseous emissions of cell cultures were analyzed and compared between several cell types. Cancerous and healthy lung cells as well as cancerous liver cells were studied. This technique carries a lot of promise as a noninvasive method of distinguishing between cell types and identifying cell pathologies. In this set of experiments, prominent variance in the rates of acetaldehyde metabolism was identified, which can potentially be used as a diagnostic method of cellular identification. Possible applications of this novel technique might extend to the medical field, where it will be used as a non-invasive detection and diagnostic tool.

Abstract: Steam assisted gravity drainage (SAGD) is one of the most popular methods used for heavy oil extraction in Canada. Of the existing sand control methods that can be used for SAGD, slotted liners can be considered among the superior ones in terms of their performance and cost of manufacturing. RGL reservoir management Inc. (RGL) is a company operating worldwide supplying sand control and flow control devices for oil extraction process. To manufacture slotted liners, RGL uses a custom made multi spindle slotting machine that has the capacity to cut 80 columns of slots at once. The manufacturing process employed by RGL has not been investigated for efficiency and opportunities to increase its production rate. In this study, RGL’s manufacturing process is taken as the case to analyze the mechanism involved in the cutting process affecting the process efficiency. The analysis results are then used to identify the major contributors to undesired conditions such as short tool life. The analysis techniques used in this research include force analysis through existing analytical and numerical models and implementing the results to conduct an in-depth analysis of the cutting dynamics. The input parameters considered are blade geometry, cutting speed, and feed rate to investigate their effects on tool life. The resulting effects on tool life are studied through the analysis of forces that are involved in the cutting process. The study of dynamics of the cutting process was also extended to determine the effect of vibration by determining the stability lobe diagram of the process. Results coupled from these two primary parts of the investigation were used to identify optimal processing conditions. The outputs from force analysis were used to compare different rake angle, relief angle, and blade material. Increasing rake angle resulted in decrease in the required force. As the rake angle increases, the relief angle should be decreased to preserve the material angle of the tooth A stability lobe diagram which is used to identify ranges for stable operation was determined by making used of the results from force distribution. The approaches employed to specify conditions for the stability lobe diagram showed that the method can be applied to analyze different combinations of tool and workpiece materials. The most common circular saw blade material was selected and its natural frequency was determined from analytical models and the literature. Existing machining constraints were also considered in determining the optimal shape. After comparing different geometries that results from optimization, a blade that has lower values for outer dimeter (2.93 in), relief angle (28o), tooth height (0.073in), and number of teeth (50); and higher values for bore diameter (1.57 in), rake angle (5o), gullet radius (0.027 in), and tooth pitch (0.184 in) than the current blade used by RGL was identified as the optimal blade.

The recent advancements in electronics and the advents of small scaled instruments has increased the attachment of life and functionality of devices to electrical power sources but at the same time granted the engineers and companies the ability to use smaller sources of power and batteries. Therefore, many scientists have tried to come up with new solutions for a power alternatives. Piezoelectric is a promising material which can readily produce continuous electric power from mechanical inputs. However, their power output is dependent upon several factors such as, system natural frequency, their position in the system, the direction of vibration and many other internal and external factors. In this research the working bandwidth of the system is increased through utilizing of two different piezoelectric beam in different directions. The dependency of output power with respect to rotation angle and also the frequency shift due to the rotation angle is studied.

Mass spectrometry has emerged as a leading tool in the field of chemistry as an analytical method for the characterization of small molecules, proteins, and other complex biomolecules. Specifically, cyclic and stapled peptides have become an intriguing class of biomolecules in drug research afforded to them because of their biological stability and resistance to proteolytic digestions. However, challenges are presented in regards to the characterization of these molecules as traditional methods are ineffective in determining a ring-opening site on the peptidic backbone. Additionally, lipid A, the hydrophobic domain of lipopolysaccharide (LPS), consists of a diglucosamine backbone and is responsible for fastening LPS to a membrane surface. Lipid A becomes a biologically relevant molecule to study as its function within LPS is directly related to the infectious and toxic properties of gram-negative bacteria, but the molecule is structurally complex and offers many challenges in terms of traditional mass spectrometry characterization. Presented in the thesis are methods to further comprehend structural motifs related to the aforementioned biomolecules. The “ornithine effect”, which describes the conversion of an arginine residue to an ornithine residue via reaction with hydrazine and subsequent preferential cyclization via nucleophilic attack of the ornithine side-chain to the neighboring carbonyl group, inducing heterolytic cleavage of the adjacent amide bond under gentle activation, is used to preferentially open cyclic and stapled rings to linearize these challenging biomolecules. Ramped collisional and photon based activation (in terms of energy and laser pulses) of lipid A molecules that contain differences in acyl-chain length and connectivity reveal general trends about the lability of certain bonds on the lipid A molecules themselves and paints a picture of the overall fragmentation trends associated with variations in lipid A structural motifs.

In scenarios such as environmental contamination or on-site nuclear analysis, an instrument capable of rapid, in-field chemical analysis would be faster and more cost-effective than the current practice of sending samples back to the laboratory for analysis. An ideal instrument for this purpose will consume little power, produce a small footprint, use small sample volumes with no sample preparation, produce no waste, and operate in ambient conditions while maintaining the high precision and accuracy needed to make time-sensitive decisions. The liquid sampling-atmospheric pressure glow discharge (LS-APGD) microplasma, developed by Marcus and co-workers, is a novel excitation source for atomic emission spectroscopy developed to meet these goals. This emission/ionization source meets the demands needed for field-capable instrumentation by being cost efficient and having a small footprint, low power consumption, high salt/matrix tolerance, and little to no waste production. The microplasma is generated in a 1-2 mm gap sheathed in a helium gas between a stainless steel electrode and an electrolytic solution. Since its conception, the LS-APGD has been used for a variety of sample mediums (e,g,, liquid, solid, and laser ablated particles) and as an elemental and an organic ionization source, and as an emission source for detection by mass spectrometry (MS) and optical emission spectroscopy (OES), respectively. Previous research employing the LS-APGD microplasma has assessed optimized components and operating parameters for multiple sample introductions and methods of detection. This work presents an analytical study of the LS-APGD microplasma as an emission source for solution samples. The goal of this research is to illustrate the capabilities of this emission source by quantitative assessment. An evaluation of the source in terms of line selection and theoretical limits of detection progresses the microplasma towards successful implementation while the analysis of matrix effects unveils broader capabilities of analysis and deeper understanding of the source. This characterization and examination of the LS-APGD microplasma, combined with past assessments, illustrates the potential of this source as a portable instrument for in-field elemental spectroscopy.

Conventional Simulated Annealing (SA) based placement methods for FPGAs give best results in terms of wirelength and critical path delay. The runtime for these SA based methods is directly proportional to the total number of cells to be placed. In case of modern multi-million gate FPGAs, SA based methods for placement dominate the total runtime in the FPGA CAD flow. In this thesis, we propose a new fast and efficient timing driven analytical placement engine targeted at global placement for FPGAs followed by low temperature SA for detailed placement. Our global placement engine uses quadratic programming approach to minimize the wirelength and dynamic net weights based on timing criticality between the blocks to minimize the critical path delay. The placement engine proceeds by iteratively partitioning the placement area and making the Configurable Logic Blocks (CLBs) move near each partition's Center of Gravity (CG). After each iteration, to calculate the timing criticality between each CLB, they are snapped to physical grid locations. The placement engine uses this timing feedback to update the net weights and calculate new coordinates for the CLBs in the next iteration. We employ a spiral legalization method in the end to obtain a legalized placement which then undergoes low temperature Simulated Annealing in VPR to give comparable or better critical path delay and 8.7% bad overall wirelength after placement. Experimental results of 20 largest MCNC benchmark circuits show that our global placement engine outperforms the state-of-the-art academic placer VPR 7.0 in terms of runtime by 30% on an average, making it scalable and provides an overall similar QoR in terms of critical path delay.

With increasing complexity of modern circuit, FPGA demands to be dealt with good CAD algorithm and suitable architecture to meet the lower non-recurring engineering cost and faster time-to-market. Placement is one of the crucial steps among them, as it decides time for implementing FPGA, routing resources and power consumption by digital circuits. Our research is centered on the placement algorithm for FPGA design. Simulated Annealing (SA) being the most popular among all the placement methods for quality results, takes huge compile time to implement larger circuits with the current new architectures. Researchers try to find a way for getting similar or better results with less run time. Based on the requirement, placement can be wirelength driven, timing driven and path driven. There are alternate ways of placement which are based on min-cut algorithm and analytic placement, and take less time. We targeted to optimize wirelength while doing placement using Gordian method in multiple iteration to get similar results as that of well-known academic research tool for FPGA - Versatile Place and route (VPR). Each iteration divides a subspace in four partitions and applies linear and bounding constraint to solve for quadratic optimization. We bypassed the placement methodology of VPR with our placement algorithm of analytical placement, implemented in MATLAB, and then fed back the output of our placer to the VPR flow for detailed placement and routing. We compare our results of placement and routing using 20 MCNC benchmarks and homogeneous VTR benchmarks with the VPR flow. Our MATLAB placer is faster by 38% with the expense of wirelength quality. It gets 1% better wirelength with 11% increase in runtime compared to the whole VPR placer after low temperature simulated annealing based final detailed placement.

The use of cyanine dyes in bioanalytical applications has become a widely explored topic of interest in chemistry. Their ability to absorb and fluoresce in the UV-visible and near-infrared region of the electromagnetic spectrum benefits their use as imaging probes and fluorescent labels due to the reduced auto-fluorescence from biological molecules. The behavior of these dyes lies in their structure which consists of two nitrogen containing heterocycles joined by an electron deficient polymethine bridge that allows specific energy transitions to occur. The first portion of this work aims to explore dye functionality for analytical applications regarding the non-covalent labeling of bovine serum albumin. The second portion of the work explores dye interactions with human serum albumin in biological membrane mimetic environments using the ternary system of sodium dioctyl sulfosuccinate (AOT) in water and n-heptane.

While previous work has demonstrated the effectiveness of nitrogen-doped carbon nanotubes (N-CNTs) as biogenic electrode materials in first- and second-generation biosensors, this thesis primarily explores enzymatic inhibition-based biosensing schemes on N-CNT electrodes. This type of scheme enables the detection of enzymatic inhibitors, as opposed to enzymatic substrates, making these inhibition-based biosensors much more suitable for the monitoring of environmental pollutants. Presented in this thesis is a biosensor which couples N-CNTs with glucose oxidase (GOx) through spontaneous physical adsorption for the highly sensitive detection of aqueous silver ions. Included is a thorough discussion of the parameters that affect response time as well the biosensor’s aptitude for repeated use. A later chapter presents initial work towards the inhibition-based detection of sucralose, a relatively new environmental pollutant. A bi-enzymatic approach is explored, in which both GOx and invertase are immobilized on an N-CNT modified electrode. Finally, shifting focus from inhibition-schemes, the last remaining chapter investigates the coupling of CNTs and N-CNTs with methylene green (MG), a redox mediator used in second-generation biosensors based on NADH oxidation. Common coupling techniques are examined for their effectiveness in decreasing the overpotential required for NADH oxidation.

Although Raman scattering has traditionally been considered a weak process, making analysis of low concentration analytes in complex matrices difficult, both methodological and instrumentation advances in the last couple decades have made Raman spectroscopy a viable and useful analytical tool.1,9 This is especially true for analyte species within aqueous environments because the Raman scattering cross-section of water is small; one particular example of a critical aqueous environment is analysis of and in blood. This review will analyze much of the literature related to Raman analysis in blood within the last 20 years, including normal Raman, surface-enhanced Raman, and spatially offset Raman analyses. The first section will focus on direct analysis of blood samples, including determining the age of deposited or donated blood and blood content within body fluid mixtures. The second section will discuss intrinsic Raman-based detection of small molecules and protein analytes within blood as well as extrinsic Raman detection of tumors. The last section will review the recent use of spatially offset Raman and surface-enhanced spatially offset Raman spectroscopy to analyze molecular analytes, tissue, bone, tumors, and calcifications, including in vivo analysis. This focal point closes with perspective on critical gaps and upcoming developments for Raman analysis in blood. Microfluidic sensing platforms facilitate parallel, low sample volume detection using various optical signal transduction mechanisms. Herein, we introduce a simple mixing microfluidic device, enabling serial dilution of introduced analyte solution that terminates in five discrete sensing elements. We demonstrate the utility of this device with on-chip fluorescence and surface-enhanced Raman scattering (SERS) detection of analytes, and we demonstrate device use both when combined with a traditional inflexible SERS substrate and with SERS-active nanoparticles that are directly incorporated into microfluidic channels to create a flexible SERS platform. The results indicate, with varying sensitivities, that either flexible or inflexible devices can be easily used to create a calibration curve and perform a limit of detection study with a single experiment. In current events, ricin has been discussed frequently because of letters sent to high-ranking government officials containing the easily extracted protein native to castor beans. Ricin B chain, commercially available and not dangerous when separated from the A chain, enables development of ricin sensors while minimizing the hazards of working with a bioterror agent that does not have a known antidote. As the risk of ricin exposure, common for soldiers, becomes increasingly common for civilians, there is a need for a rapid, real-time detection of ricin. To this end, aptamers have been used recently as an affinity agent to enable the detection of ricin in food products via surface-enhanced Raman spectroscopy (SERS) on colloidal substrates. One goal of this work is to extend ricin sensing into whole human blood; this goal required application of a commonly used plasmonic surface, the silver film-over-nanosphere (AgFON) substrate, which offers SERS enhancement factors of 106 in whole human blood for up to 10 days. This aptamer-conjugated AgFON platform enabled ricin B chain detection for up to 10 days in whole human blood. Principle component analysis (PCA) of the SERS data clearly identifies the presence or absence of physiologically relevant concentrations of ricin B chain in blood. Spectrophotometry and colorimetry experiments are common in high school and college chemistry courses. Previous work has demonstrated that handheld camera devices can be used to quantify the concentration of a colored analyte in solution in place of traditional spectrophotometric or colorimetric equipment. This paper extends this approach to an investigation of a mesogold mineral supplement. With the addition of free Google applications, the investigation provides a feasible, sophisticated lab experience, especially for teachers with limited budgets.

Typically, researchers underestimate the effect of temperature, amongst other inputs such asload, creep and shrinkage, in a structure. Even when this is not the case, it is treated ascompletely independent and worthy of generating error-free predictions about the current stateof a structure. There have been various methods used, under the broader context of StructuralHealth Monitoring in literature, and most have been feature-extraction-based solutions.This thesis introduces Eigen Residuals, which is mathematically derived from PCA. I shall showthat knowledge from this, and Eigen Slope, better models a truss bridge member's response tochanges in strain as a result of driving inputs. There are instances where existing systemmodels for a structure's members are inaccurate, and PCA System Modeling solves thischallenge.Next, I establish a monitoring threshold using equi-probability contours, and incorporateknowledge of expected structural relationships between members. I proceed to develop asystem-wide multi-member bridge monitoring algorithm, using Eigen Residuals in a multivariateapproach. Members validate each other (via a voting system for events of significance), andprovide an extra layer of intelligence.Our final results show an improved system model for individual members of a truss bridge. Inaddition, the multi-member algorithm eliminated false alarms that were generated, and providedextra information to the Ohio Department of Transportation, for bridge maintenance purposes.

Graphene is a newly available conductive material ideally suited for forming well-defined interfaces with electroactive compounds. Aromatic moieties typically interact with the graphene surface to maximize Van der Waals interactions, predisposing most compounds to lie flat on its basal plane. A tripodal motif binds multivalently to graphene through three pyrene moieties and projects easily varied functionality away from the surface. The thermodynamic and kinetic binding parameters of a tripod bearing a redox-active Co(II) bisterpyridyl complex were investigated electrochemically. The complex binds strongly to graphene and forms monolayers with a molecular footprint of 2.3 nm2 and a [DELTA]Gads = -38.8 ± 0.2 kJ mol-1. Its monolayers are stable in fresh electrolyte for more than 12 h and desorb from graphene 1000 times more slowly than model compounds bearing a single aromatic binding group. Tripods with naphthalene or phenanthrene moieties also desorb more rapidly than those with pyrene, but reach greater monolayer densities. Noncovalent functionalization also allows assembled functionality to behave dynamically on the surface, afeature not observed in conventional self assembled monolayers. In addition, while biomacromolecuels adsorbed on bare graphene can lose their function, tripods bearing N-hydroxy succinimidyl ester groups immobilize both antibodies and Concanavalin A without loss of function. This result represents an important step forward in the design of flexible biosensors and provides a modular method for engineering the surface chemistry of graphene for biological applications.

An investigation of the structural behavior and corrosion resistance of hybrid fiber reinforced polymer (FRP) wrapped steel reinforcement bars for use in reinforced concrete structures. The investigation is comprised of a bar analytical model using laminate theory, an in-depth analytical model for reinforced concrete sections, and a series of experimental tests to assess the structural performance and corrosion resistance of the composite bars. A comparison between the analytical model and experimental results was conducted and general design guidelines developed. Using these guidelines, sample designs were completed using hybrid bars, stainless steel bars, and standard epoxy coated steel reinforcing bars. The designs were compared and a life cycle cost (LCC) analysis was performed to assess the economic advantages or disadvantages of the hybrid bars. Conclusions and recommendations for standard practice and design and future research are then presented.

Most human organs consist of solid tissues. Most human disorders occur in solid tissues. No two cells are equivalent in native solid tissues as single cells widely vary in their biochemistry, specialization, and location. Yet, the fundamental limitations of solid-tissue processing and analysis have made it challenging to access the richness of molecular information in single cells of animal and human solid tissues. We have eliminated a set of limitations of solid-tissue processing and analysis. In this thesis, I first describe a new method for sampling single cells in live solid tissues. This method preserves the molecules of all molecular classes and thus fulfills the precondition for multiplexing within and across molecular classes. I then describe new analytical methods and strategies for massively multiplex analysis within and across molecular classes in each sampled single cell. Standard curves, the basis of analytical methods, can be constructed in all measurements and signals can be mapped to the corresponding quantities. Proof of principle experiments are presented. These methods will enable the quantification of the molecular mechanism of each sampled single cell in solid tissues by analytically measuring tens of proteins, transcripts and/or metabolites at once. By performing these measurements in human solid-tissue biopsies, we will be able to define a new category of diagnostic tests, to personalize single-cell pharmacology and to rapidly identify mechanistic biomarkers and drug targets.

The purpose of this study was to determine the feasibility of using a liposomal formulation for the systemic delivery of a GC-C agonist peptide drug. Peptide drugs have increased in numbers lately but are limited by delivery challenges. Liposomes can overcome some of those challenges. Peptides themselves are sensitive to processing conditions but GC-C agonists are stabilized by multiple disulfide bonds. Processing conditions, lipid types and drug solutions for preparing liposomes were evaluated. The drug load efficiency and peptide degradation were measured by quantitation of the drug and impurities by HPLC. The formation of multimers was monitored by size exclusion chromatography. Two prototype batches were stored at two temperatures to determine the stability of the liposomal formulation. The peptide degradation, multimer formation, and leakage rate was evaluated. The results discussed here show the feasibility of liposomes containing linaclotide to be developed as a formulation that may be functionalized with PEG or a mucoadhesive polymer that has potential to be used in an inhaler, nasal pump, or other new delivery system that can utilize a liposomal solution to deliver the drug to systematic targets, although further optimization is needed before a scaled-up, commercial formulation is realized.

Creatine (Cr) was initially discovered in the 1830s by a Frenchman named Chevreul. In subsequent years, it was discovered that creatine was utilized by the musculatory system, which fueled research on its overall use as a metabolite in the human body. Investigation into the role of this chemical in the human body led to its current use as a sports supplement and potential treatment option for individuals with musculatory disorders such as Parkinson’s and Huntington’s. With creatine’s increased use as a sports supplement there is also a strong interest in its long term effects, as well as its potential as a treatment option. There is need for further investigation as well as a means for dosage determination, and a method that will allow for accurate concentration determination. The current methods used to determine creatine concentration are time consuming and complicated analytical methods such as high pressure liquid chromatography (HPLC) and gas chromatography-mass spectroscopy (GS-MS). A single reagent enzymatic assay (Cr assay) that can be used on any bench top chemistry analyzer for accurate and precise measurement of Cr in human serum and aqueous samples was developed and is summarized here. The assay can measure samples in 10 minutes, is linear from 0-15mg/dL of Cr, the reagent has a shelf life of 45 days refrigerated. The Cr assay is within 98% accuracy, run to run CV from 1.6-5.3% for clinical samples and a sample-to-sample CV of less than 0.5%. This assay can easily be adapted for any bench top chemistry analyzer that has the capability of a programmable channel, and can read clinical samples with accuracy, precision and reproducibility.

Paper (and other cellulose-based materials such as cotton thread and fabrics) are underexploited as materials for the construction of “high-tech” and “lab-on-a-chip” devices. One major drawback of paper is its tendency to absorb water from the environment and, with wetting, to change its mechanical properties; other challenges relate to control over the attachment of molecules (e.g. antibodies, DNA) and cells on its surface, and to the addition of electronic function. The goal of this thesis is to develop paper as a substrate for a range of applications— microfluidics, substrates for electronic systems and MEMS, low-cost diagnostics, cell biology, and optics. The approach involves chemically modifying the surface of the paper to provide new functions without altering any of its defining properties: mechanical flexibility, foldability, light weight, gas permeability, and low cost. The first part of my thesis describes the modification of paper by silanization with organosilanes such as alkyl- and fluoroalkyl trichlorosilanes in the gas phase. Here, silanization is used to lower the surface free energy of the paper and to minimize the tendency of paper to absorb liquids and vapors, and especially water. Chapter 1 and Appendix 3 demonstrate that the combination of long fluoroalkyl chains of grafted siloxanes with the micro-scale roughness and porosity of paper yielded a material that is omniphobic (both hydrophobic and oleophobic), while preserving the properties of mechanical flexibility and low resistance to transport of gas of the untreated paper. Appendix 3 shows that features of omniphobic paper can be used to construct microtiter plates and liquid-filled gas sensors using standard paper folding techniques, while Appendix 4 shows that new type of microfluidic device fabricated by carving microchannels into the surface of omniphobic paper. The resulting devices have open, unobstructed channels (with dimensions as small as 45 μm) and thus exhibit fluid dynamics similar to conventional PDMS-based microfluidics, but are much lighter and have the potential to be much less expensive than PDMS-based devices. The second part of my thesis is focused on engineering the surface of paper to enable efficient immobilization of capture and target molecules for bioanalysis. In one approach, described in Appendix 5, we exploit the ease with which the surface chemistry of paper (i.e. the surface of the cellulose fibers making up the paper) can be modified, in order to enhance the immobilization of antibodies and antigens on the surface of the paper via hydrophobic interactions, while preventing the wicking of the fluids into the paper substrate. As an application in low-cost diagnostics, we describe a low-cost electrochemical device for ELISA intended for use in resource-limited settings. In a second approach, described in Chapter 2, we developed of an efficient procedure for assembling microarrays of ssDNA and proteins on paper, at the lowest practical cost. This method starts with the synthesis of DNA oligonucleotides covalently linked to paper, and proceeds to generate ssDNA arrays that, through hybridization with complementary strands of DNA, are capable of simultaneously capturing DNA, DNA-conjugated protein antigens, and DNA-conjugated antibodies. The third part of my thesis describes the simple, inexpensive fabrication of electrodes for paper-based electrochemical systems. A first method describes, in Appendix 6, the development of inkjet printing as a method for high resolution printing of conductive patterns on omniphobic “RF” paper, both to extend its promise as a substrate for paper electronics, and to enable us to integrate it into our program in low-cost, paper based diagnostics. A second method, described in Chapter 3, circumvents the need for printing, and instead focuses on the fabrication and reconfiguration of simple, versatile, and inexpensive electroanalytical devices in which conventional stainless-steel pins—in unmodified form or after coating with a carbon paste—are used as electrodes., Chemistry and Chemical Biology

Geological storage of CO2 in deep saline formations is one of the promising ways to reduce emissions of CO2 into the atmosphere. This is because of the mature technology as a result of the experience in oil and gas extraction and the fact that saline formations offer large capacity and immediate availability. However, not all saline formations are suitable for CO2 storage. One of the important selection criteria for a suitable formation is the existence of sufficient injectivity. Injectivity simply shows how much CO2 can be injected into a saline formation for a constrained pressure build-up. One of the most important constraints in CO2 storage is to keep injection well pressure below formation fracture pressure. Otherwise, formation can be fractured which can create pathways for CO2 to escape from containment. Hence, significance of estimating injectivity should not be underestimated. Analytical models are preferred in preliminary studies to estimate pressure build-up. This thesis presents new analytical tools to estimate pressure build-up at CO2 injection wells in saline formations. The models developed in this thesis assume injection of CO2 at constant rate through vertical wells into homogenous and horizontal formations of constant thickness. They model the effects of relative permeability, CO2 dissolution in formation brine and drying-out on pressure build-up. Analytical solutions are presented for three types of formation outer boundary conditions: closed-boundary, constant pressure-boundary and infinite-acting formation. Using these models, transient pressure behaviour of fully-penetrating wells, partially-penetrating wells and multi-well injection are examined. The predictive capability of analytical models for each case is tested using numerical reservoir simulations. The results show a good agreement between the analytical and numerical computations. For partially-penetrating wells, a total skin factor which is composed of mechanical skin, partial penetration pseudo-skin and two-phase flow effects is introduced. Using the models developed for multi-well injection, the effects of number of injection and pressure relief wells as well as formation properties on total injection rate are studied.

Transient mass transfer in a diffusion-reaction biofilm with a moving boundary was investigated analytically. The analysis incorporates both the diffusion processes into the biofilm as well as the reaction processes that lead to the expansion of the system. For first and second order reaction terms, the biofilm synthesis as a function of time was presented. The temporal development of the biomass was found to be in very good agreement with numerical results. The effects of osmotic pressure and temperature were also investigated and it was found that osmotic pressure plays a significant role in first order reactions but the temperature dependence is primarily found in the reaction kinetics and does not significantly influence osmotic pressure effects.

Individualist and collectivist cultural approaches describe the relationship between an individual and his or her social surroundings. the current study had a two-fold purpose. the first was to investigate whether Brazilians, like other collective peoples, displayed more group self-representations, categorized items more relationally and paid more attention to context than Americans. the second purpose of this study was to investigate if counter-cultural primes played a role in activating either collective or individual selves. Both American (n = 100) and Brazilian (n = 101) participants were assigned either to a no-prime condition or a counter-cultural prime condition and then were asked to rate emotion cartoons, categorize items, complete the Twenty Statement Test (TST), and choose a representative object. As expected, unprimed Brazilian participants displayed more collectivist patterns on emotional (F[1,196] = 10.1, p = .001, ?²= .049; F[1,196] = 7.9, p = .006, ?²= .038; F[1,196] = 9.0, p = .005, ?²= .044) and cognitive (F[1, 196] = 6.0, p < .01, ?² = .03) tasks than Americans. However, Brazilians offered more individualist self-representations (F[1, 195] = 24.0, p < .001, ?² = .11) than American participants. Priming only had a marginal effect on item categorization (F[1,194] = 3.9, p = .051, ?² = .02). Understanding such cultural differences is necessary in the development of clinicians’ multicultural competence. Therefore, these findings, along with the strengths and limitations of this study and suggestions for future research, are discussed.

Within this educational endeavor instrumental development was explored through the investigation of microwave induce stable electromagnetic waves within a non-linear yttrium iron garnet ferromagnetic waveguide. The resulting magnetostatic surface waves were investigated as a possible method of rapid analytical evaluation of material composition. Initial analytical results indicate that the interaction seen between wave and material electric and magnetic fields will allow phase coherence recovery andanalysis leading to enhancement of analytical value. The ferromagnetic waveguide selected for this research was a high quality monocrystalline YIG (yttrium iron garnet) film. Magnetostatic spin waves (MSW) were produced within the YIG thin waveguide. Spin waves with desired character were used to analytically scan materials within the liquid and solid phase.

Abstract: Two-dimensionally (2D) braided tubular composites have been utilized in a wide range of applications including medical equipment such as braided stents and catheters. Catheters are long flexible tubes used in catheterization procedures, such as angiography and ablations. In this thesis, angiographic catheters were specifically targeted; which are referred as “catheters” for the remaining of the document. Catheters are typically used with guidewires which provide structural support to the often low rigidity catheters. In some catheterization procedures, it may be beneficial to use a 2D braided catheter for increased control and maneuverability in the body. The 2D braided catheter, if designed properly, may provide all the required rigidities for a successful procedure and decrease the dependency to the guidewire compared to conventional catheters. Hence, use of 2D braided catheters may decrease the procedure time, may provide superior control of the device due to its design, and may also decrease the inherent patient discomfort. A thorough understanding of 2D braided composites is of absolute necessity considering the delicate use of medical equipment, such as catheters, in the human body. The aim of this PhD thesis is to address the shortcomings of the available models in the literature by developing an analytical model geometrically consistent with small braided tubular structures and provide all the necessary tools possible to design a target specific braided catheter. An analytical model that accounts for the effect of diameter of a braided tubular product on the elastic properties, needed for catheter design, was developed. Parametric studies were conducted to highlight the effects of the change in radius on elastic properties of braided composites. Case studies that underline the important geometrical parameters that affect predictions were conducted and findings discussed. Effect of increased undulation length on elastic properties of braided composites was also investigated. The findings were compared to experimental work using three different fiber/matrix system composites. As predicted by the model, a decrease in the properties was observed experimentally; however, this decrease was found to be more important than predicted. Possible reasons for this behavior are discussed in the view of composite materials and geometrical factors. The experimental findings of the open-mesh composites were also used to further validate a regression based model available in the literature. Lower linearity limit values for the regression based model were calculated for longitudinal elastic and shear moduli predictions.

Lowell Liebermann, born in New York City in 1961, is one of America's most distinguished living composers. In addition, he often conducts and performs as pianist in his own works. His musical language is unique and unmistakably rooted in the grand tradition of Western music; however, his style combines old and new, simple and complex, emotional and intellectual aspects. It combines tuneful, catchy melodies with a rich harmonic language, all framed by a strong formal design. This study begins with presenting primary information on this concerto excerpted from an interview with Lowell Liebermann. This interview served as a reference for subsequent sections, and a transcript of the interview is appended to the end of this study. In the third chapter, the musical language of the composer is discussed. Chapters four and five constitute the main body of this dissertation. The goal of these two chapters is to understand the basic three-pitch motive of the work, to demonstrate how it operates at various levels, and to see how the raw material corresponds at a larger structure level. It is the author's hope that this study will guide performers to better understand Liebermann's Concerto No. 1 for Piano and Orchestra, Opus 12.

The theory of viscoelasticity has been a classic topic, but its application to the modeling of flexible pavement has not been so successful even though viscoelasticity has long been characterized in asphalt concrete (AC). This is mainly owing to that the time-dependent property of a viscoelastic material is always very challenging and also that flexible pavement is a layered structure which further complicates the modeling work. This work establishes an efficient and accurate semianalytical solution for primary response (stresses, strains, and displacements) of flexible pavement on the ground of layered viscoelastic theory (LVET).Chapter I highlights the development of flexible pavement. On account of the viscoelastic AC, the theory of linear viscoelasticity is reformulated briefly from a mechanical standpoint. The material characterization and the constitutive equation for viscoelastic AC are reviewed.In Chapter II, pavement response to a moving load is expressed by the convolution integral of the pavement impulse response and the moving load. This convolution integral is elaborated, and in so doing the history of viscoelastic modeling of flexible pavement is reviewed and summarized.Pavement impulse response, the kernel of pavement response, is introduced in detail in Chapter III. Making use of the Prony series for a viscoelastic material, pavement impulse response is established numerically in the space domain and, for the first time, analytically in the time-domain. Such solution is called the semianalytical solution.To verify the semianalytical solution established in Chapter III, Chapter IV establishes the semianalytical solution for pavement response under the stationary load. This semianalytical solution is verified with a finite-element-based method through numerical examples, after which, the well-known collocation method is examined.Chapter V proposes the semianalytical solution for pavement response under moving dynamic load. The semianalytical solutions under various typical loading conditions are verified with the Abaqus solutions.Main conclusions are summarized in Chapter VI. Future works needing further research are suggested.

Cellular chemistry is controlled by affinity interactions between biomolecules. Quantitative analysis of such interactions is important for understanding cellular chemistry and developing drugs and chemical probes. Capillary electrophoresis (CE), as a valuable approach to binding studies, allows multiple sample components including bound and free species to be separated under electric field. In this work, we have developed CE-based methods for analysis of Src homology 2 (SH2) domain protein binding systems. A Fluorescence anisotropy CE (FACE) method was developed for the detection of SH2-Bbeta under equilibrium conditions. A fluorescein labeled peptide containing the SH2 domain recognition sequence was used as the affinity probe and was incorporated in the electrophoresis buffer. Besides purifed SH2 domain, the FACE assay was also applied to cell lysate containing full length SH2-Bbeta. For kinetic measurements, two CE-based methods were developed, compared and evaluated using Fyn and SH2-Bbeta as models. Complex half-life (t1/2 ) was measured in either competitive mode with unlabeled ligand spiked in sample and competition monitored by CE, or noncompetitive mode with dissociation intentionally allowed by adjusting the separation time and t1/2 extracted from peak shapes. By optimizing the injection and separation conditions, t1/2 ranging from 0.7 to 50 s were measured. The competitive CE assay was also explored for possible drug screening applications using SH2 domain proteins as models as they are interesting pharmaceutical targets. In a multiplexed high-speed CE assay, three SH2 domain proteins, Fyn, Src and SH2-Bbeta, were separated and inhibitors screened against these proteins simultaneously. A non-specific and a specific inhibitor were identified and IC50s were quantitatively determined from peak height of the complex detected at different inhibitor concentrations. Another screening technique developed is on-line HPLC-APCE, which has potential application in screening of effective components from complex mixtures. Three potential peptide inhibitors were separated by HPLC and change in complex peak heights was observed when peptides that interfered with binding eluted from the column. A chromatogram was reconstructed using the peak heights from series electropherograms collected by CE every few seconds. These studies have demonstrated the capability of CE for quantitative measurement of affinity interactions, kinetics and screening.

A microfluidic separations-based sensor was developed to incorporate push-pull perfusion sampling, on-line derivatization, flow-gated injection, electrophoretic separation and fluorescence detection for neurotransmitter monitoring. The device allows in vivo measurements of neurochemical changes with both high temporal and spatial resolution, which is important for uncovering the role of neurotransmission in behavior, pharmacological response, and disease. First, peptide neurotransmitter candidate activity screening is described to illustrate the previous state-of-the-art in high speed neurotransmitter monitoring. The microdialysis, capillary electrophoresis laser-induced fluorescence (CE-LIF) instrument employed allows for separation of 5 amino acid neurotransmitters (glutamate, aspartate, gamma-aminobutyric acid (GABA), glycine, and taurine) as well as several metabolites in under 10 s. Three of six novel proenkephalin peptides tested elicited a response when perfused into the striatum. While a powerful analytical technique, spatial resolution is limited by the 1-4 mm length of the dialysis probes preventing measurements in all but the largest brain regions of rats. Furthermore, the method requires dedicated personnel to build and operate the instrumentation thus preventing widespread use in the neuroscience community. A microfluidic device was sought to enable facile operation and portability through miniaturization. Devices were created in poly(dimethylsiloxane) (PDMS) because its tunable elasticity allows the formation of valves and pumps through multilayer soft-lithography. A microfluidic push-pull perfusion sampling device was created and shown to allow on-line sampling with improved spatial resolution over microdialysis. After demonstration of feasibility, other analytical operations were incorporated onto the device including flow-gated injection onto an embedded fused silica capillary, separations in PDMS microchannels, and embedded optical fibers and waveguides for fluorescence excitation and collection of emission. The final prototype incorporates sampling, derivatization, injection, separation, and detection and is capable of detecting dynamic changes in eight neurotransmitter concentrations simultaneously and serially for up to 4 hours. Separation efficiencies of 500,000 theoretical plates and detection limits between 30 and 60 nM were demonstrated with the device. The capability to deliver pharmacological agents and quantify subsequent changes in the neurotransmitter profile was also demonstrated. Future directions of this technology are also proposed.

With piezoceramic materials, it is possible to harvest power from vibrating structures. It has been proven that micro- to milliwatts of power can be generated from vibrating systems. We develop definitive, analytical models to predict the power generated from a cantilever beam and cantilever plate. Harmonic oscillations and random noise will be the two different forcing functions used to drive each system. The predictive models are validated by being compared to experimental data. A parametric study is also performed in an attempt to optimize the cantilever beam system's power generation capability.

By examining conflicting analytical approaches to late nineteenth- and early twentieth-century tonal music in terms of their unspoken assumptions and philosophical commitments, I hope to identify some of the criteria by which we might validate or invalidate competing theoretical accounts of the same music. My dissertation develops a meta-theoretical framework for evaluating methodologies, and in doing so, it provides insight into a body of late-tonal music that seems resistant to any single approach. A critical problem confronting people who study tonal music of the late nineteenth- and early twentieth-century is the lack of consensus concerning an analytical approach. In the work that attempts to engage this music, the Schenkerian, Schoenbergian, and neo-Riemannian analytical methodologies represent the most widely used and criticized approaches. Is there a common denominator among the Schenkerian, Schoenbergian, and neo-Riemannian methodologies that would allow us to critically compare them? How do we resolve the differences that arise between theories that offer conflicting accounts of the same empirical domain? As a possible solution to the questions of theoretical conflict, I suggest we turn to the ideas of historical philosopher Michel Foucault. I propose that a Foucauldian perspective might view the competing Schenkerian, Schoenbergian, and neo-Riemannian methods as participating in a triangle of knowledge defined by hierarchy, context, and symmetry. This triangle, analogous to Foucault's quadrilateral of eighteenth-century general grammar, represents the discursive formation or the space in which the knowledge of the Schenkerian, Schoenbergian, and neo-Riemannian methods is made possible. As I believe, each approach's epistemic commitments are based on its acceptance or rejection of these three philosophical presuppositions, and my dissertation explores how aspects of knowledge in the three theoretical models can be linked to some positive or negative constellation of hierarchy, context, and symmetry. One of the most important consequences of an archaeological evaluation is that it can uncover the deep, underlying structures that order knowledge within these three theoretical models, and show theorists who choose one approach over another how a methodology may, in fact, be connected to a seemingly opposed approach through common philosophical presuppositions.

Design methodologies based on intellectual property (IP) reuse have been widely accepted as a solution to the design complexity problem. Fast and accurate electronic design automation (EDA) tools are required to evaluate key design characteristics of IP-based designs. In particular, efficient and effective power estimation methodologies for the design of low-power high-complexity IP systems are crucial. Power macromodeling is a promising approach in achieving fast and accurate power estimation. In this thesis, I present theoretical and empirical results for power estimation of IP-based systems using analytical macromodeling. Specifically, a novel sequence generator is developed to improve the accuracy of the power macromodel characterization. A new analytical macromodel is described to incorporate the power effect of input glitches. More importantly, a novel hybrid methodology for estimating power in programmable IP systems is presented. The hybrid nature of the proposed method stems from the combination of a static power estimation kernel for datapaths and an outer shell of functional simulation, which captures the control signals that affect the flow of the data and, consequently, the utilization and power dissipation of hardware. Experimental results have demonstrated that our technique computes power estimates hundreds of times faster than state-of-the-art commercial gate-level power tools with only 5% average estimation error.

This research investigates several key issues dealing with the metal cutting principles that govern the operation of drills. A model has been developed for predicting the heat partition into the workpiece in dry drilling. An oblique cutting analysis and an advection heat partition model calculate the heat flux loads on a finite element analysis of the workpiece. Experiments using embedded thermocouples have verified that the model predicts the temperature field in the workpiece reasonably well for a range of drilling speeds and feeds. A study of the effects of thermal distortions in dry drilling combines analyses of the flow of heat into the workpiece and drill. The model predicts the effects of thermal distortions of the drill and workpiece on the diameter and cylindricity of dry drilled holes. Experiments using thermocouples embedded in the workpiece and drill have verified the accuracy of the model. The model predicts that for typical industrial drilling processes, thermal distortions of the drill and workpiece lead to oversized holes with a bell shape. A drill-foil thermocouple system has been developed, which measures the temperature distribution along the cutting edges of a drill. The method can be used for high-speed drilling processes and is simple to implement. Experiments have shown that the method is accurate, produces repeatable measurements, and is sensitive to the drilling conditions, including the speed, feed, and drill geometry. The nature of the indentation zone and its contribution to the total drilling thrust force have been revealed. A three-dimensional mathematical model for the geometry of the indentation zone and an expression for the radius of the indentation zone have been developed. Experiments using a ductile workpiece and an enlarged chisel edge have verified the accuracy of the expression for the radius of the indentation zone. Simulations indicate that the thrust force contributed by the indentation zone increases with feed and wedge angle, and for a typical twist drill, the indentation zone can contribute almost four percent of the total drilling thrust force.

As the number of corneal refractive procedures increases annually, concerns about their long-term stability and predictability have become the center of attention in the ophthalmic community. This thesis focuses on developing quantitative biomechanical models of the cornea that will overcome shortcomings of previous models and incorporate new observations of corneal elastic properties. Our intent is to provide a more accurate model of the corneal structure to guide current and future developments. The second chapter shows that neural networks could rapidly prototype practical solutions to obtain a better estimate of the average corneal power using the contrast and image size parameters provided by the topographic systems. After establishing improved measurements of the corneal shape the thesis focuses on the development of various corneal models. The analytical model proposed shows that geometric optics, corneal structural properties and surgical nomograms could be used to gain a better understanding of corneal response to surgical interventions. The predictions of this model are closer to the values provided by the published nomograms and clinical data than that obtained by the traditional geometric model. Three surgical procedures (Ultrafast Laser-Automated Lamellar Keratomileusis, Corneal Transplant and Intrastromal Refractive Keratectomy) were simulated using the finite element method. A new formulation was developed that simulates the changes on corneal curvature after refractive surgery when the stiffness inhomogeneities across the corneal thickness are considered. It has been shown that the predictability of the surgical outcome is improved when the stiffness inhomogeneities and nonlinearities of the deformations are included in the finite element simulations. Moreover, a finite element formulation has been developed first time to characterize the intrastromal refractive keratectomy procedure. An inhomogeneous (small displacements) model was identified as an acceptable representation of the corneal biomechanical response to this novel technique. The formulations developed and clinically tested in this study were able to calculate how the curvature changes are mediated by alterations in the stress-strain relationship of the corneal tissue. Non-uniform stress-strain relations found at the laser-treated zones are among the most important results of the model. In addition, the model verified that the cornea weakens centrally after intrastromal treatment of the mid-periphery.

Exposure to air contaminants in non-industrial indoor workplaces has become a general public health concern. Among the contaminants found in such environments, volatile and semi-volatile organic compounds ((S)VOCs) have attracted the most attention because of their ubiquity and possible etiologic roles in sick building syndrome. Currently, determining the presence and concentrations of (S)VOCs rely on labor- and capital-intensive sample collection and laboratory analytical methods, which limit the quality and quantity of data collected. The primary goal of this research is to develop a portable indoor-air quality (IAQ analyzer for the determination of complex (S)VOC mixtures at low part-per-billion (ppb) concentrations. The key features of the instrument are a multi-adsorbent preconcentrator/focuser, a dual-column, high-speed separation module with tunable retention capabilities, and a detector comprising a microfabricated sensor array whose output provides a characteristic 'fingerprint' of each analyte. An emphasis is placed on the development of the preconcentrator/focuser. Results demonstrate that with proper design the tradeoffs between maintaining adequate capacity as well as efficient thermal desorption efficiency can be achieved. Variables affecting the performance of the preconcentrator/focuser are investigated and modeled, and it is shown that a 3-adsorbent bed containing only 12 mg of adsorbent material can quantitatively capture and thermally desorb more than 40 compounds at 100 ppb each in a 1 L sample volume. The detector utilizes an array of three polymer-coated surface acoustic wave (SAW) sensors in addition to characterizing detector performance, an investigation is made of the fundamental mechanisms governing responses in such sensors, which arise from changes in the polymer mass and modulus upon vapor sorption. A previously established model is revised based on the new finding of a partition coefficient bias and the consequent recognition of the importance of free volume effects on sensor responses. Through laboratory testing and modifications in the design of the prototype instrument, conditions are established for optimizing the separation, recognition, and quantification of the components of a mixture of 30 (S)VOCs at low-ppb concentrations. Chamber testing assesses performance as a function of environmental variables and concentration fluctuations and demonstrates that results are comparable to those obtained from standard methods.

The concept of spectroelectrochemistry using an ATR system has been explored in our research group for a number of years. To date the concept of achieving a sensor with multimodes of selectivity has been demonstrated with potassium ferrocyanide, Ru(bipy) 3 2+ , and Ru(CN) 4 - . This sensor has three modes of selectivity: applied potential, chosen wavelength and chemically selective film. In this sensor device in order for an analyte to be detected it must first partition into the sensing film, be electroactive at the applied potential, and have a change in absorbance at the wavelength of light. In the first part of my research, I evaluated expanding the sensor concept to detect an analyte which itself did not undergo electron transfer at the electrode and which is not optically monitored. To explore this system a mediated electrode reaction was used in which the mediator undergoes spectroelectrochemical modulation. The analyte is detected indirectly by its effect on theoptical signal from the modulated mediator. The system explored was that of ascorbic acid as the analyte and Ru(bipy) 3 2+ as the mediator using a composite film of Nafion-SiO 2 . Factors such as scan rate, concentration of mediator in the film, film composition and thickness, and analyte solution pH was studied to achieve optimal sensor conditions. This concept can be further expanded in developing a biosensor. This concept was explored using mediated detection and the addition of an enzyme. Investigation into to developing a more selective glucose biosensor was explored as well as several different mediators for this reaction. The final part of my research was development of a sensor capable of determining the concentration of technetium in various chemical forms (mainly pertechnetate) in the vadose zone and ground water at the U.S. DOE Hanford site. In this research Re and Mn are being used as a chemical surrogate for radioactive Tc. The chemical and electrochemical reduction of ReO 4 - , and MnO 4 - was explored as well as its reaction with several different classes of ligands. Both the electrochemical and optical properties were studied.

This thesis investigates and analyzes the design of dynamic systems composed of a mechanical structure and feedback controller. Conventionally, the process is decoupled with the controller design subsequent to that of the structure. This thesis presents an analytical method that simultaneously optimizes both the structural and control design variables. The problem is reparameterized from one of choosing structure and control design variables to one of choosing desired performance, which is more intuitive and involves fewer variables. This method determines the space of performances that are both stable and achievable given the structural feasibility and control effort constraints. The method then allows for the determination of the set of structural/control design variables that achieve a given performance, with the minimum control effort. This method is applied to a simple illustrative example. Performance and control effort norms are based on the solution of an algebraic Lyapunov equation, which has both stochastic and deterministic interpretations. Further, this thesis investigates the effects of expanding the use of closed-loop analysis beyond performance and control effort. For the first time closed-loop dynamics are accounted for in constraints on structural fatigue, buckling and the time derivative of control effort (actuator rate saturation). The effects of this are analyzed in a case study on a new boring tool, called the Smart Tool. This tool, which utilizes piezoelectric actuation and laser photo sensors to actively isolate a cutting insert from erroneous bar motion, has significant interaction between active and structural elements. Both geometric dimensions and the controller gains are optimized simultaneously to minimize a single objective function.

In order to meet the ever-increasing demand for energy, a worldwide transition away from fossil fuels to renewable solar–fuels is required. However, the intermittency of local insolation mandates a cost-effective and efficient storage scheme. Using solar-derived electricity to drive the thermodynamically uphill water splitting reaction to generate dihydrogen and dioxygen is one promising method of storing solar energy in fuels. This “artificial photosynthesis” scheme requires the execution of two half-reactions, one involving the oxidation of water to O2—the oxygen evolution reaction (OER)—and the other entailing the reduction of hydrogen ions to H2—the hydrogen evolution reaction (HER). Accomplishing these electrocatalytic reactions stresses the development of catalysts that are capable of mediating reactions that are in net multi-electron, multi-proton transformations. Transition metal oxides are known to be promising candidates for mediating the OER and their electrocatalytic properties have been studied extensively and optimized for operation at pH extremes. In contrast, intermediate pH OER has been relatively underexplored and the influence of proton-coupled electron transfer (PCET) reactions on OER kinetics of these materials at close-to-neutral pH has for long remained unclear. The OER studies described here have focused on elucidating the underlying mechanistic basis for the catalytic behavior of a class of structurally disordered first-row transition metal oxides, with an emphasis on intermediate-pH catalysis and proton–electron coupling. At a fundamental level, understanding how protons and electrons may be managed and coupled to engender improved activity remains of great importance to the design of new electrocatalysts. To this end, the synthesis and study of homogeneous HER catalysts bearing functional groups in the second coordination sphere that can modulate proton–electron coupling is particularly interesting. The HER studies presented here discuss this important issue within the context of metalloporphyrin catalysts possessing proton relays., Chemistry and Chemical Biology

Global energy demand is predicted to increase at an alarming rate over the next century; in order to meet this demand while also limiting the effects of runaway climate change, society will need to shift toward renewable sources of energy. Many of the fundamental chemical transformations that store renewable energy as fuel require the addition or removal of protons. Optimization of catalysts that carry out these transformations can be achieved with proton management at the molecular level. Deliberate construction of molecular catalysts with an intramolecular proton relay is one strategy for controlling the movement of protons during catalysis. These so-called “hangman” catalysts have been shown to increase the rate of catalysis in the cases of hydrogen evolution, oxygen reduction, hydrogen peroxide dismutation, and olefin epoxidation. A new class of hangman porphyrins is now available on the gram scale and can easily be further modified, allowing for unprecedented control the strength and character of pendant proton relays. Using iron complexes of these new hangman porphyrins, the level of control over proton management is demonstrated with the variation in the rates of hydrogen evolution electrocatalysis depending on the nature of the proton relay in the second coordination sphere. Understanding the fundamental electron transfer reactions of reactive oxygen species (ROS) is important in the chemistry of renewable energy storage, but also in a biological context. Hydrogen bond donors are known to affect the electron transfer reactivity of ROS, with the strength of the hydrogen bond determining the nature of oxygen-oxygen bond activation. The catalytic performance of iron corroles towards peroxide dismutation is markedly enhanced by the presence of a pendant hydrogen bond donor which is also capable of transferring protons to bound substrates. Contrary to hangman corroles, the six hydrogen bond donors in hexacarboxamide cryptand do not readily transfer protons, allowing it to facilitate the chemically reversible two-electron reduction of dioxygen to “naked” peroxide dianion. Using electrochemical techniques and computational modeling, it is possible to use cryptand-encapsulated peroxide as a model for the electron transfer reactions within lithium-oxygen batteries., Chemistry and Chemical Biology

It has recently been recognized that built-up bracing members designed by current practice are quite susceptible to premature failures when subjected to severe earthquake motions, thus, endangering the survival of braced structures during severe ground motions. Bracing members experience large excursions in cyclic tension and post-buckling range. During a cyclic deformation, plastic hinges form in a member at the ends and at mid length. The Ductility and energy dissipation capacity of a bracing member in post-buckling range mainly depend on the performance of these plastic hinges under reversed cyclic rotations. Current design practice does not consider this aspect of the behavior. Seventeen full-scale bracing members made of double angles in A36 steel with welded stitches and end gusset plates were tested under large cyclic deformations representative of severe earthquakes. Three types of section configuration were investigated which included conventional back-to-back, strengthened back-to-back, and boxed section configuration. The following four conclusions are made. First, early fracture due to local buckling is the common mode of failure of conventional back-to-back angles. Second, strengthening of conventional back-to-back angles by welding two inclined plates does not improve member response due to unsymmetric buckling. Third, boxed angles have the most effective section configuration in which, with continuous stitch plate and adequate stitch strength, section distortion can be virtually eliminated. Fourth, end fixity causes shift of the end plastic hinges into the member which significantly enhances the member response. An analytical criterion has been established to modify the overall strength of built-up struts to account for shear flexibility of these members. Furthermore, analytical equations have been derived to calculate the shear strength required between the components of built-up struts to ensure behavior identical to that of an integral section, at the time of first buckling as well as in post-buckling range which is of interest in seismic design. The equations are applicable to any built-up strut with general end conditions.

A multidimensional detection system for biological molecules has been developed. This system involves the technique of supersonic jet expansion, laser desorption sample introduction, resonance enhanced multiphoton ionization (MPI) and a time-of-flight mass spectrometer (TOFMS) detector. Several novel experiments have been performed with this system including analytical jet spectroscopy studies and multiphoton ionization mass spectrometry. In this thesis, the development and application of resonant two-photon ionization (R2PI) jet spectroscopy is discussed. In particular, R2PI jet spectroscopic analysis of biological molecules using laser desorption with entrainment into supersonic jet expansion is presented. The jet-cooled spectra for biological molecules including tyrosine derivatives, indoles, catecholamines, and dipeptides are obtained and studied. It is shown that this method is a sensitive probe of small structural changes and thus can be used for the unique identification of the molecule under study. The potential of analytical application of the jet spectroscopy technique is also demonstrated in terms of sensitivity and selectivity. The typical detection limits for these molecules are in the low pg region and the selectivity obtained by optical analysis can be as high as 10 ppm. In addition, MPI mass spectrometry studies of peptides, nucleosides and other biologicals are discussed. The study of the potential of this technique for peptide sequencing of aromatic and nonaromatic peptides is presented. It is also shown that the combination of jet spectroscopy and MPI mass spectrometry can provide high selectivity and high sensitivity for detection. Finally, these two techniques are used for the detection of thin-layer chromatography with pulsed laser desorption/volatilization into supersonic jet expansions.

The mechanical behavior of fiber-reinforced SiC/Si$\sb3$N$\sb4$ ceramic matrix composites has been analytically and experimentally studied. Experimental approaches for the mechanical testing of ceramics composite materials is discussed. Approaches used for the gripping of single fibers were also investigated; this investigation included the influence of misalignment on fiber strength. Both aligned and misaligned single fiber testing was conducted. Also the stiffness properties of the fiber was measured and the bending strength of the fiber was determined. It was shown that the bending strength of the fiber is extremely high compared to the tensile strength. The monotonic tensile testing of SiC/Si$\sb3$N$\sb4$ composite results a discontinues stress/strain behavior. The tensile fatigue testing which was conducted at 10 Hz cyclic loading showed a gradual failure of the composite. Also the hysteresis and the ratcheting were observed. The hysteresis behavior which was observed during the cyclic loading of SiC/Si$\sb3$N$\sb4$ composites was analytically modeled. It was shown that the interfacial friction forces which are produced along a debonded fiber/matrix interface give rise to stress-strain hysterises. The influence of the axial and radial residual stresses to the interfacial on debonding was explored. A new model for interfacial failure in fiber-reinforced ceramic composites was developed. This model was used to analyze experimental approaches for determining interfacial shear, such as fiber pushout and pullout specimens produces a stress singularity in the fiber/matrix interface; under this residual loading, debonding can propagate along the interface. For a brittle material, the fiber/matrix interface can easily fail during the pullout test due to this stress singularity. It was shown that the debonded fiber may separate from matrix under tensile loading which results complete debonding. Because the fracture of the interface may produce a rough surface which gives a rise to a false bonding effect.

In a reinforced concrete building subjected to earthquake type loading the beam to column connections constitute one of the critical regions and they must be designed and detailed to dissipate large amounts of energy without a significant loss of stiffness or strength. In the experimental part of this study, six full size interior beam-column subassemblages were tested under quasi-static loadingwhich was intended to simulate earthquake input. All specimenswere designed following the accepted design philosophy of strongcolumn-weak beam approach. The three variables selected forthis investigation included the percentage of transverse hoopreinforcement in the joint ((rho)(,t) = 0.75% to 1.15%), the joint shearstress level (10SQRT.(f(,c)'(' )to(' )15SQRT.(f(,c)') and the presence of transversebeams and slab on half of the specimens. On the basis of test results it was concluded that the joint shear stress level was critical for the satisfactory performance of beam to column connections without transverse beams and slab. For connections with transverse beams and slab, a well confined joint core was essential for the effective participation of the transverse beams in resisting joint shear. For the evaluation and design of joints, a joint performance index is proposed which integrates the effect of pertinent variables influencing the joint behavior. For detailing, an odd number of layers of hoops in the joint is recommended with a nimimum of three layers. In the analytical part of this study, a hysteretic model for beam-column subassemblages is developed from the hysteretic behavior of specimens observed during testing. The proposed model accounted for pinching of hysteresis loops, stiffness degradation, reduced unloading stiffness and fixed end rotations due to the slippage of bars through the joint. A simple analytical model for computing the maximum story displacements for regular frames is proposed. This model idealized a building frame as an elastic column with rotational restraints at the floor levels. Three building frames of five, seven and ten stories were analyzed using the SIMPLE program developed specifically for this model. The maximum story level displacements were found to be in good agreement with those obtained from more complex models.

The studies reported here have shown that the exploding graphite fiber bundle plasma system is well suited for the direct trace elemental analysis of samples in both solution and particulate form. The analytical utility of the exploding graphite fiber bundle plasmas has been demonstrated under a variety of conditions. Linear analytical curves were obtained for several elements. Detection limits in the range of 5-20 ng were obtained for Cr and Mn under a variety of discharge conditions. Detection limits in the low microgram range were obtained for Pb. The cylindrical geometry of the graphite fiber bundle plasma makes it amenable to magnetic field confinement using the theta-pinch configuration. Benefits arising from the use of the magnetic field in conjunction with the plasma include better line radiation reproducibility, reduced particle size effects, lower continuum radiation intensity, and greater linearity for analytical curves. The effect of the magnetic field on the plasma was enhanced by the unidirectional capacitive discharge system. Time resolved photoelectric measurements show a reduction in continuum radiation of over 50% relative to an equivalent oscillatory discharge; neutral and ion line radiation intensities were relatively unchanged. The unidirectional discharge system also demonstrated more efficient spatial confinement of continuum radiation intensity.