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Although the transesterification reaction of triglycerides with alcohols is well known and practiced on a commercial scale (using acid or alkaline catalysts), there is plenty of scope to improve this process. One approach involves the use of heterogeneous catalysts that could be retained in a fixed bed, and this would enable a continuous process to be developed. With this aim in mind, zinc proline (Zn(C5H8NO2)2) was used as a catalyst, which was coated onto a cordierite monolith support (62 cells/cm2). Two different coating methods were explored, and SEM images of the surface revealed interesting crystal structures on the surface of the cordierite. Experiments were then performed in a batch reactor (120 ml) to assess the activity of the catalyst (molar ratio methanol:rapeseed oil = 12:1, T = 195ºC and P = 20 bar, 2 h duration). Although high conversions could be achieved, the catalyst was found to lose activity with time, and even the cordierite support was also found to be catalytically active. These aspects were explored further, in a continuous flow reactor, which had an i.d. = 6.2 mm, and multiple heated sections (500 mm each) into which pieces (10 mm long) of catalyst coated monoliths were inserted. Experiments were performed with packed lengths of 200 and 400 mm, and with liquid flows ranging from 0.1 to 2.9 ml min-1. Although it was shown that high conversions can be achieved over extended run-times (e.g. 100 to 200 min), it was clear that the catalyst was losing its activity. Measurements also showed, that during the course of an experiment, Zn was leaching, and this clearly contributed to catalyst deactivation Despite the loss in activity of the zinc proline catalyst, the reaction system developed in this thesis was shown to work well, and that it could be used to evaluate the performance of catalytically coated sections of monolith. To demonstrate the use of this system, a few scoping studies were also performed using SrO as a catalyst, which was coated onto the cordierite monolith.

Abstract: This thesis reports the study of flow inside a honeycomb type substrate. Honeycomb monoliths are extensively used in the automotive industry, as substrates in the exhaust gas after-treatment system. The flow approaching a honeycomb monolith is usually highly turbulent; However, once entering the channels, turbulence dissipates because of a dramatic reduction of the Reynolds number. The first part of the honeycomb channels can be very active in terms of chemical reactions and can impact the performance of the entire system significantly; Therefore, it is important to study the flow regime transition and other phenomena occurring in that area. The flow regime, pressure drop and convective heat transfer when flow enters, passes through and leaves the substrate are analyzed. Computational models at a channel and a converter scale are used. At a converter scale, the honeycomb is modelled as a continuum, meanwhile, for channels, a discrete model is used. Laminar and turbulent flow approaching the monolith are considered. The cases with turbulent flow are modelled with Reynolds-Average Navier-Stokes (RANS) models and Large Eddy Simulation (LES). According to the results, the turbulence approaching the honeycomb in fact dissipates inside the channels, but does not lead to a steady flow, instead of that, the flow becomes laminar unsteady. When turbulence effectively enters the channels, it enhances the convective heat transfer in the entrance length; However, in the laminar unsteady region, both the pressure drop and the convective heat transfer coefficient are similar to those for steady laminar flow. Regarding the exit of the substrate, when flow leaves the channels behaves like a jet, and under certain conditions, it generates turbulence, even when the flow inside the channels is steady. The generation of turbulence is promoted by a higher channel velocity, remaining turbulence inside the substrate and pulsating flow inside the channels, and it is also affected by the channel shape. A new strategy to obtain a realistic decay and generation of turbulence in converter scale simulations using the continuum approach is proposed. The new strategy corrects nonphysical flow regime transitions observed in previous models. A new pressure drop model for flow through a honeycomb is presented. The model accounts for the effects of flow entering, developing and leaving the substrate, and can be applied for circular, square, triangular and hexagonal channel cross-sections. A new correlation for the apparent permeability of a continuum modelling a monolith is reported. The correlation is based on the friction factor inside a monolith channel and accounts for a realistic inlet velocity profile and the hydraulic entrance length. New correlations for the convective heat transfer coefficient at a constant wall temperature and a constant wall heat flux when laminar flow is entering into a circular cross-section monolith channel are reported. The correlations consider temperature-dependent fluid properties. For the case with a constant wall temperature, when the heating rate is high, the curve of the convective heat transfer coefficient along the channel has a minimum significantly lower than the asymptotic value. Correlations available in the literature are only valid for monotonically decreasing curves; Hence, a new mathematical expression that combines a decreasing function with a sigmoidal one is used. A methodology to calibrate such a model is also presented. A methodology for modelling the effect of the upstream turbulence when it enters the channels on the convective heat transfer coefficient is proposed. Finally, a wall-flow filter, which is a particular type of honeycomb with porous walls, is analyzed. The developing of the flow inside the filter is investigated. A criterion to consider the flow as fully developed is presented. It is found that the friction factor in the filter channels is different from that of pipes with non-porous walls, as usually assumed. An improved pressure drop model, based on first principles, is proposed.

Organic plastic scintillators are employed as radiation detectors in industries and are used for nuclear safeguard applications. They are durable, can be produced at low cost and can readily be used in portable devices, making them ideal for field detection work. Their fast decay time also allow them to discriminate different types of radiation making them useful in various applications. Still, their drawbacks include low Z value resulting in limitations on the energy resolution and the ability of identification of radioactive sources. To resolve this issue dopants such as dyes and nanoparticles are added into the polymer matrix in an attempt to enhance either light yield and/or the overall Z. Nanophosphors such as quantum dots is a popular choice due to their tunable emission and energy transfer properties. However, over the past decade the coupling of these nanocrystals, having emission in the visible wavelength, with plastic scintillators were not very successful. In the current dissertation, a different approach is implemented using nanophosphors in the UV region. Cadmium Sulfide quantum dots with near UV emission is embedded into plastic scintillating system under minute loading. Scintillation efficiency was enhanced at different weight loading of dyes and quantum dot, characterization was also performed at various ionizing energies demonstrating improvements. The study was further expanded with different dyes and polymer combination displaying various degree of enhancement and quenching through energy transfer effects. Lastly, deep UV emission ZnO nanocrystals were synthesized to further study the energy transfer effects of the dye and polymer combination. The fabrication process and results are discussed in the following.

As one of the core building blocks of life, proteins play a central role in our efforts to understand, control, and engineer the natural world. Chemical modification of proteins facilitates these efforts by allowing manipulation of protein properties and creation of new materials. A variety of methods for the modification of proteins exist, and collectively these methods have enabled the synthesis of drugs, the study of biological systems, and the creation of new materials. Unfortunately the exquisite control provided by many of these methods does not extend to oligomeric proteins, which are found ubiquitously in nature. These proteins often have symmetries and structures that make them particularly appealing for use in materials science and pharmaceutical applications, yet their multivalency makes their controlled modification difficult. This thesis describes the development of a method for protein modification in which control over the number of modification sites is exerted through noncovalent interactions. This method is able to control the level of modification of both monomeric and small oligomeric proteins. Further development revealed that this method also discriminates between different modification sites, such that it could be used to site-specifically modify proteins or monitor bioconjugation reactions. Finally, the principles used in the construction of these bioconjugation strategies were applied to the recovery of enzymes from industrial reactions.

The creation of a monolith concerning internet culture and technology on Cleveland's historic mallpresents a number of cultural and architectural questions. This thesis will address the emergenceof technology and internet based culture as new drivers for architectural form and meaning. Therelationship between architecture and historic legacy has significant impact on our cultural conscious.Cleveland's historic malls, conceived by Daniel Burnham as part of the national City Beautiful movement;have become an integral part of the City's urban and social atmosphere since their inception in 1903.The transformation of Cleveland from and industrial powerhouse to a struggling rust-belt economyhas created a unique juxtaposition of underutilized public space within established cultural icons andinstitutions.A relationship between new program and existing city form and landscape must be handled bothelegantly and deliberately. Decisions being made will have a concrete effect on the importance ofhistory within the future of the city. E-sports, competitive electronic gaming, is an industry experiencingtremendous growth along with increased exposure and profitability. Integral to technology, e-sportsrepresents the future of non linear architectural space Providing a facility for such a unprecedentedprogram does not come without challenges. Creating such a place within the cultural and historicallegacy of Cleveland's Malls offers a number of additional theoretical and physical challenges.By embracing the existing infrastructure of classical American cities, architecture can operate for notonly the future but the past and present as well.

Abstract: In this thesis, the development and use of a transient heterogeneous 2D model for monolithic catalytic converter is presented. Study on the cold flow hydrodynamics, temperature effect and CO conversion and light off behaviour of different models is developed. Different models are studied based on different parameters such as monolith brick CPSI configuration, size of the converter, inlet cone sizing and inlet velocity of the converter. The results for both steady state and transient modes are presented in detail. It is shown that monolith brick CPSI has a significant effect on pressure drop and light-off behaviour of the converter. Also, converter size has a major effect on the performance of a converter. Inlet cone sizing showed to have a significant effect on the hydrodynamics of the converter but it did not have a major effect on light-off behaviour of the converter.

Abstract: The research presented in this work explores the application of microfluidics to the field of proteomics through the design of a multi-channel microfluidic platform and the investigation of individual components of the system. The design of this microfluidic device allows the integration of several protein sample preparation steps for automated electrospray ionization mass spectrometric (ESI-MS) analysis, including protein separation, fractionation and collection, preconcentration and cleanup, and protein digestion. In order for the multi-channel system to function properly, I first evaluated each individual component of the device. Several areas were explored: (i) optimization of polymer monolith for solid-phase extraction (SPE) preconcentration; (ii) investigation of cationic coatings for microchannel surface modification to facilitate positive electrospray of peptides and proteins for chip-MS coupling; (iii) combination of the hydrophobic monolith and the PolyE-323 coating in a single channel device for on-chip SPE and on-bed tryptic digestion with on-line coupling to ESI-MS. Multiplexed microfluidic devices for protein analysis, which integrate a series of microfluidic features, were then designed, built and tested. The multiplexed microfluidic architecture employed a separation channel, a fractionator, an array of microchambers to accommodate monolithic polymer for SPE preconcentration, and an elution channel for the detection of eluted sample using fluorescence detector or mass spectrometer. The performance of the multiplexed devices for integration of multiple analytical steps was explored with sequential fractionation, collection, and elution of fluorescent sample, evaluating the ability to trap and release individual fractions without cross-contamination. Thorough analysis of each of the individual components on the multiplexed microfluidic platform provides valuable insights into the design of such systems, which brings us closer to our final goal of a proteomic processing microchip.

LAD, ANKIT RAGHUNATH. Flow Modeling for Micro-filtration through electro-statically charged monolith filters. (Under the direction of Dr. Andrey V. Kuznetsov.) This study is a multi-physics problem which aims at modeling fluid flow through electro-statically charged monolith filters with machined micro-channels. The multi-phase fluid (air) considered has suspended micro particles which are the impurities to be filtered out. The resulting particle trajectories due to the effect of the forces exerted on the particle such as the hydrodynamic drag, the electrostatic force of attraction and repulsion and Brownian diffusion are studied. The micro-filtration process is studied under the presence of an electric field developed due to the uniform density charge distributed over the channel surface. The model is validated by comparison with the experimental result. The advantage of using repulsive electric field instead of attractive electric field for filtration is studied. The unit cell filtration system is developed for normal and cross flow and the scope for efficiency improvement is tested. The possibility of ‘selective filtration’ is examined by using the multiple filter layer model and the role of different hole-orientation pattern is also studied. The experimental setup of the filtration system and the filter material strength for practical applications is discussed.

Silica-based monolithic HPLC columns contain a novel chromatographic support in which the traditional particulate packing has been replaced with a single, continuous network (monolith) of porous silica. The main advantage of such a network is decreased backpressure due to macropores (2 μM) throughout the network. This allows high flow rates, and hence fast analyses that are unattainable with traditional particulate columns. The Chromolith SpeedROD™ (EM Science, Gibbstown NJ) is a commercially available silica-based monolithic column. This work investigated the chromatographic properties of the 50x4.60 mm (ODS) SpeedROD™. Data fit to the van Deemter equation (mean square error=0.834) indicated that the van Deemter model was valid for monolithic columns. An effective particle size of 4 μM for the SpeedROD™ column was assigned by comparing the minimum of van Deemter curves with a series of particulate columns having various particle diameters. Separation Impedance (E), an empirically derived measure of column performance, was calculated as an alternate method of evaluating column efficiency. Data collected using this model confirmed monolithic columns behaves as a (more efficient) 3 μM column. A series of experiments were designed to compare the effects of mobile phase strength and mobile phase viscosity between the SpeedROD™ column and a particulate column. The results indicated both solvent strength and viscosity have effects on the monolithic column at the optimum linear velocity. A fast (90 s) HPLC method was developed using the SpeedROD™ column and a seven-component test mixture with a large range of hydrophobicities. The precision for both retention time and peak area was measured at high linear velocities (8 mL/min) and the percent relative standard deviation (RSD) calculated. Column to column reproducibility (n=6) was measured. The overall percent RSD ranged from 0.25% to 4.56% for retention time and from 1.08% to 6.77% for peak area. Run to run reproducibility (n=15) was measured for all six columns. Averages ranged for retention time from 0.89% to 5.09% RSD and for peak area from 4.65% to 6.18% RSD. Applications for the SpeedROD™ column with various sample types were developed and discussed. These methods demonstrated the effectiveness of the SpeedROD™ at fast flow rates.

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