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Title: INVESTIGATION OF OXYGEN GENERATION DURING THE OPERATION OF LITHIUM-ION CELLS USING IN-SITU FLUORESCENCE SPECTROSCOPY
Creator: Li, Mo
Date: 2016, 2016-07
Description: An ex-situ fluorescence spectroscopy system was set up and utilized to study the interaction of fluorescent dyes with an oxygen quencher. The...
Show moreAn ex-situ fluorescence spectroscopy system was set up and utilized to study the interaction of fluorescent dyes with an oxygen quencher. The Stern-Volmer relationship was obtained and fitted to correlate the partial pressure of oxygen to the dye fluorescence intensity. The oxygen quenching constant α for 30 μM 9,10-dimethylanthracene_(DMA) dissolved in the mixture of ethylene carbonate_(EC) and dimethyl carbonate_(DMC) (1:1 volume ratio) were 0.69/0.62 at high/low partial pressure of oxygen. Operation of the self-made pouch cells with LiCoO2 as the cathode material was examined by charging/discharging at C/10. The discharge capacities were 107 and 104 mAh/g for the pouch cell both with and without the optical probe, which indicates that the optical probe did not significantly affect the performance and capacity of the cell. The optical probe was inserted into the pouch cell to measure the fluorescence intensity of the dye that was dissolved in the electrolyte. Time series experiments before charging demonstrated that the fluorescence intensity was stable for at least 24 hours. However, the fluorescence intensity decreased abruptly as the voltage of the pouch cell increased during the initial stages of charging, which means that the dye (DMA) could not be employed to detect the oxygen generated in the cell. Both the real-time fluorescence spectroscopy and the cyclic voltammetry illustrated that this dye was not suitable for the in-situ fluorescence tests. The electrochemical stability at room temperature of different dyes such as anthracene, Palladium (II) meso-tetrakis (pentafluorophenyl porphyrin)_(PTTFPP) and Platinum octaethylporphyrin_(PtOEP) were examined in the organic solvents used in the electrolytes in Li-ion cells. Cyclic voltammograms of anthracene and PTTFPP showed oxidation peaks at 2V and reduction peaks at around 1V, with the possible formation of the radical anion causing spectral changes. The chemical compound 1-hexyl-3- methylimidazolium bis (trifluormethylsulfonyl)imide_(HMIM BTI) was electrochemically stable, but the fluorescence intensity was too low (5% of dye DMA) to be used in the in-situ detection of oxygen. As a result, more work must be performed in the future to find a suitable dye. Keywords: fluorescence spectroscopy, in-situ Li-ion cell operation, quencheroxygen, the Stern-Volmer relationship
M.S. in Chemical Engineeering, July 2016
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Title: AN EMPIRICAL APPROACH TO GASSIFICATION PROCESS MODELING AND ASSESSMENT
Creator: Rahmaninejad, Fatemeh
Date: 2013-05-01, 2013-05
Description: There has been growing interest in estimating the flow rate and composition of fuel gases produced from gasification of coal and other...
Show moreThere has been growing interest in estimating the flow rate and composition of fuel gases produced from gasification of coal and other carbonaceous solid fuels. In general, coal gasification processes are complex, and because of the high costs associated with the experimental investigations, modeling and simulation tools are needed to assist with the design, analysis, and optimization of these complex processes. Most of the efforts in the development of gasifier models have focused on two different approaches; equilibrium modeling and kinetic modeling. The chemical equilibrium approach assumes the gasification reactions have sufficiently fast kinetics and reach global chemical reaction equilibria, which leads to over-prediction of the extent of the gasification reactions [1, 2, 3]. On the other hand, the kinetic based models require detailed knowledge of hydrodynamic and reaction kinetics of the heterogeneous and homogeneous chemical reactions [4, 5]. Because of the dependence of the product gas (composition and flow rate) on a broad ranges of certain key operating variables such as gasifier design, configuration, and coal type the gasification model needs to take into account the effect of those parameters based on available experimental data. In this study, a versatile and user-friendly gasifier simulation model was developed which incorporates a MS Excel interface aiming to provide a guide to gasification process analysis, evaluation and improvement. The model uses a set of empirical “default” correlations, for the reaction conversions that were obtained from xi regression analysis of the available experimental data to predict the syngas composition, flow rate, and performance of the gasifier based on the operating conditions specified by the user. The results of the parametric studies performed for assessment of the effect of operating conditions are discussed and presented.
M.S. in Chemical Engineering, May 2013
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Title: The hydrogenation of coal tar and coal tar oils
Creator: Melichar, Robert S.
Date: 2009, 1919
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/hydrogenationofc00meli
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 36

Title: Heat treatment of high speed steels
Creator: Miller, Philip F, Bornstein, Hymen
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/heattreatmentofh00mill
Thesis (B.S.)--Armour Institute of Technology, 1911 B.S. in Chemical Engineering, 1911

Title: PROTEOLYTIC STABILITY OF FIBRONECTIN CONJUGATED TO POLYETHYLENE GLYCOL: EFFECT OF PEG LENGTH TO CYSTEINE RESIDUES
Creator: Hekmatfar, Sogol
Date: 2013, 2013-07
Description: Fibronectin (FN) is an essential protein of the extracellular matrix (ECM) needed in wound healing. In chronic wounds, the high levels of...
Show moreFibronectin (FN) is an essential protein of the extracellular matrix (ECM) needed in wound healing. In chronic wounds, the high levels of protease in the wound bed lead to excessive degradation of fibronectin, which delays the healing process. Developing a proteolytically stable and functionally active form of FN is the main purpose of this research. Conjugating of proteins to polyethylene glycol (PEG) or PEGylating proteins showed more proteolytic stability than native FN degradation without perturbing their activity. The goal of this study was to compare the proteolysis of native and PEGylated fibronectin with different PEG length. Fibronectin was purified from human blood plasma and conjugated to PEG Diacrylate (PEGDA) and other types of PEG to yield the PEGylated human plasma fibronectin (PEG-HPFN). α-chymotrypsin and neutrophil elastase were used as digestion enzyme during degradation reaction. The proteolysis reaction was stopped at different time points with protein inhibitor phenylmethanesulfonylfluoride (PMSF). The samples were analyzed by SDS-PAGE followed by silver staining or immunblotting with antibodies specific to human fibronectin. Densitometric analyses of the polyacrylamide gels or the blots demonstrated that PEG-HPFN was more stable than native HPFN. The results demonstrate that PEGylation is a robust approach for stabilizing fibronectin. Future studies into activity of PEGylated proteins as well as the role of PEGylation factors such as extent of PEGylation or PEG length on activity will provide novel strategies of mitigating fibronectin degradation in chronic wounds.
M.S. in Chemical Engineering, July 2013
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Title: STABILITY OF AQUEOUS FOAMS: FOAM FILM STRATIFICATION PHENOMENON AND THE EFFECTS OF DISPERSED VERSUS SOLUBILIZED OIL
Creator: Lee, Jongju
Date: 2016, 2016-05
Description: A foam is a system consisting of a concentrated dispersion of gas bubbles in a liquid. Foams are encountered in many industries such as food,...
Show moreA foam is a system consisting of a concentrated dispersion of gas bubbles in a liquid. Foams are encountered in many industries such as food, agriculture, chemicals, petroleum, and paper manufacturing. Aqueous foams are formed by using surfactants or nano-colloidal particles. Thin liquid films containing surfactant micelles or other nano-colloidal particles are considered to be the key structural elements of foams containing gas and liquid. We thus probed the effects of the micellar concentration and the film size (area) on the stability of a dry bulk foam by studying the stability of a single foam lamella containing micelles; this is so we can establish the importance of the micellar structuring phenomenon and the foam film size (area) affecting the bulk foam stability. The film stratification phenomenon (stepwise film thinning) was experimentally observed by the reflected light microinterferometry. The stepwise layer-by-layer decrease of film thickness is due to the appearance and growth of dark spot (of one layer less film thickness) in the film. We used the two-dimensional diffusion model to model the dynamics of dark spot expansion considering the apparent diffusion coefficient and the film size. Based on this model, we carried out a parametric study depicting the effects of film thickness (or the number of micellar layers) and film area on the rate of dark spot expansion. Many practical applications involving three-phase foams (aqueous foams containing oil) commonly employ surfactants at several times their critical micelle concentration (CMC). We investigated the influence of both the dispersed and solubilized oils, and the surfactant concentration (above CMC) on the stability of an aqueous foaming system. In foam stability, the relative importance of the dispersed oil versus oil solubilized within the micelles depends on the stability of the aqueous asymmetric (i.e., pseudoemulsion) film between the oil and the air-water interface and the second virial coefficient. Also, the micellar structuring phenomenon tests using the single foam lamella revealed that the multi-layering structure was well pronounced in the absence of the solubilized oil; as a consequence, the foam lamellae thinned slowly layer-by-layer and the oil solubilized in micelles weakened the micellar structure formation. The foam lamellae thinned faster, making the foam less stable.
Ph.D. in Chemical Engineering, May 2016
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Title: Methods for the oxidation of potassium manganate
Creator: Johnson, F. R., Pearson, A.
Date: 2009, 1918
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/methodsforoxidat00john
Thesis (B.S.)--Armour Institute of Technology

Title: MODELING AND COMPUTATIONAL FLUID DYNAMICS SIMULATION OF A BUBBLING FLUIDIZED BED PROCESS AT DIFFERENT SCALES
Creator: Jang, Jungkee
Date: 2012-11-14, 2012-12
Description: In recent years there has been increased research activity in the experimental and numerical study of gas-solid flow system in the bubbling...
Show moreIn recent years there has been increased research activity in the experimental and numerical study of gas-solid flow system in the bubbling fluidized bed process. The bubbling fluidized bed process have numerous applications in the energy, pharmaceuticals, and chemicals process industries since it has provides a number of advantages such as large heat capacity inside a bed, and rapid heat and mass transfer rate. A reliable design and scale-up approach for a bubbling fluidized bed process requires a very detailed model based on the fundamentals of multiphase transport phenomena. The present works address the simulation and scale-up of rather complex gas-solid flow behavior in bubbling beds using Computational Fluid Dynamics (CFD) approach. The CFD model developed in this study which is based on two fluid model was used to optimize the performance and utilized as a scale-up tool for an isothermal and a non-isothermal bubbling fluidized bed process. For isothermal case, 2-Dimensional and 3-Dimensional simulations of bubbling beds for both PSRI laboratory and large scales fluidized beds using a kinetic theory approach were performed. The FLUENT code was used to conduct the simulations. Our simulation results were validated and refined by comparing them with the laboratory-scale experimental data of PSRI. Then, our modified 2-D and 3-D CFD models were used to predict the large-scale PSRI bubbling fluidized bed performance at different operating conditions. In our 3-D simulations, we used exactly the same bed dimensions and inlet configurations (such as air distributor) as the experimental one to predict the characteristics of gas-solid flow patterns in the PSRI large-scale bubbling fluidized bed. The numerical simulation results compared well with both PSRI large scale experimental xx data on pressure drop and time-averaged void fraction near the wall, which could be a very good proof for demonstrating the capability of CFD as a tool to be used in the design and scale-up of bubbling fluidized bed systems. For non-isothermal case, the set of equations necessary to describe the flow patterns and heat/mass transfer phenomena of bubbling beds at three different scales were developed. CFD simulations were performed to investigate the characteristics of pharmaceutical particle drying process in bubbling fluidized beds at three different scales (e.g., lab, kilo, and 10-kilo scales). The results of CFD simulation were compared with the experimental data obtained at laboratory-scale (Duquesne University experiments), to validate and refine our CFD model. The modified model was used to simulate the drying of the same material in Abbott laboratory kilo and 10-kilo scale units. Our simulation results for solid particles drying as a function of dimensionless time showed that our CFD model along with similar dimensionless group similarity approach can be used as a tool to scale-up the drying process from experimental scale to both kilo-scale and 10-kilo scale fluidized bed dryer. Moreover, to determine the optimum particle mixing, numerical simulations were performed at different particle diameters, bed heights, inlet velocities and inlet velocity distributions, respectively. The numerical simulation results compared well with the experimental data (performed by Duquesne University and Abbott laboratory) on moisture removal rate and outlet gas temperature. This also could be a very good proof for demonstrating the capability of CFD as a tool to be used in the design and scale-up of non-isothermal bubbling fluidized bed processes.
PH.D in Chemical Engineering, December 2012
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Title: INVESTIGATION OF PERFORMANCE AND DURABILITY OF POLYMER ELECTROLYTES FOR ELECTROCHEMICAL ENERGY STORAGE AND CONVERSION TECHNOLOGIES
Creator: Jung, Min-suk
Date: 2016, 2016-07
Description: Polymeric ion exchange membranes are integral components of electrochemical conversion/storage devices such as fuel cells, water electrolyzers...
Show morePolymeric ion exchange membranes are integral components of electrochemical conversion/storage devices such as fuel cells, water electrolyzers, and redox flow batteries. There has been dramatic progress in the research and development of cation exchange membranes (CEM). Nafion® (perfluorosulfonic acid membranes) is one example of a state-of-the-art CEM and has been successfully demonstrated in various electrochemical energy devices. Unlike CEMs, anion exchange membranes (AEMs) have been of limited utility to date due to their drawbacks, including poor chemical/mechanical stability and low ionic conductivity. However, alkaline environments result in better activity for electrochemical reactions and afford the possibility of using non-platinum group metal (PGM) electrocatalysts. AEMs, therefore, are still being studied in order to resolve existing challenges in terms of conductivity and stability in alkaline media and in strongly oxidizing solutions. In this work, AEMs derived from different types of polymer backbones were prepared, and their chemical stability and electrochemical property were investigated. Polysulfone (PSF) AEMs were prepared by first chloromethylating polysulfone, then by functionalizing chloromethylated polysulfone (CMPSF) with different base reagents. PSF-trimethylamine (TMA) AEMs showed a 40-fold reduction in vanadium (IV) ion (VO2+) permeability when compared to a Nafion® membrane and exceptional oxidative stability after exposure to a 1.5 M vanadium (V) ion (VO2 +) solution for 90 days. PSF-TMA AEMs were successfully demonstrated in the all-vanadium redox flow battery. Excellent energy efficiencies (>75 %) were attained and sustained over 75 chargedischarge cycles for a vanadium redox flow battery prepared using the PSF-TMA separator. Crosslinking of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) AEMs using diamine was tried with intentions to improve the mechanical stability and electrochemical property of PPO AEM. Crosslinked PPO AEMs (30 ± 4 % at 25 oC) showed less liquid water uptake than non-crosslinked PPO AEMs (46 ± 5% at 25 oC) while maintaining comparable ionic conductivities (hydroxide ion conductivity of 45 mS/cm at 60 oC). Crosslinked PPO AEMs maintained mechanical integrity and still showed some mechanical stability (ultimate tensile strength of 3~4 MPa and elongation at break of 13~17 %) after exposure to 1 M KOH at 60 oC for 14 days, while noncrosslinked PPO AEMs completely lost their mechanical durability. Finally, this dissertation presents research related to perfluorinated AEMs prepared using a Grignard reagent. These membranes exhibited 0.7 mmol/g of Cl- ion exchange capacity (IEC), 20 mS/cm of hydroxide ion conductivity at 20 oC, and 10 % of water uptake at room temperature. The membranes also maintained 90 % of their initial conductivity after an exposure to 1.5 M VO2+ in 3 M H2SO4 solution for seven days.
Ph.D. in Chemical Engineering, July 2016
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Title: The low temperature distillation of a Wyoming coal
Creator: Bolte, C.l., Durant, R.f.
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/lowtemperaturedi00bolt
Thesis (B.S.)--Armour Institute of Technology

Title: Investigation of the chemical literature
Creator: Barrows, Frank E.
Date: 2009, 1919
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/investigationofc00barr
Thesis (B.S.)--Armour Institute of Technology

Title: ELECTROCATALYSTS FOR ALKALINE WATER ELECTROCATALYSIS
Creator: Jain, Anchal
Date: 2016, 2016-07
Description: Hydrogen is an attractive energy carrier and is part of an idealistic future wherein it serves as a clean energy source. In the presence of...
Show moreHydrogen is an attractive energy carrier and is part of an idealistic future wherein it serves as a clean energy source. In the presence of oxygen, it can be converted to water in fuel cells with the release of heat and electrical work. Electrolysis of water is an important route to hydrogen generation. Alkaline water electrolysis is preferred over electrolysis in acidic medium due to the possibility of lowering stack costs and enhancing the library of stable electrocatalyst materials available for the electrochemical reactions. The high anode overpotential arising from the sluggish oxygen evolution reaction (OER) has led to significant interest in developing stable and active OER electrocatalysts. IrO2 (state of the art catalyst), RuO2 and PGM-based pyrochlores are suitable catalyst materials that exist today, but there is benefit in finding cost-effective alternatives. In this study, the pyrochlore oxides containing non- Platinum Group Metals (non-PGM) metals were synthesized by solid state reaction and were tested for their OER activity but none of the materials tested, exhibited OER activity and a comparison was attempted between the pyrochlores containing PGM metals as against those containing non-PGM metals. Additionally, perovskite oxides of the form La[Ni(1-x-y)CoxFey]O3 (where 0≤x≤1 and 0≤y≤1) were synthesized by the co-precipitation method. Many of these perovskites exhibited electron conductivities greater than 0.1S/cm, eliminating the need to add carbon for OER studies and implying the likelihood of making conducting electrodes with these materials without the additives like carbon. The perovskites LaNi0.6Co0.4O3 or LaNi0.6Fe0.4O3 with x/y =0.4 had conductivities of the order of 10S/cm. The electrocatalytic activity for the OER was studied using a rotating disk electrode (RDE) in 0.1M KOH and catalyst loading of ~100μg/cm2. The perovskite LaNi0.5Co0.5O3 (x=0.5, y=0) had the onset potential of ~1.50V against RHE, and all these perovskites had onset potentials ~0.1-0.15V higher than the benchmark IrO2 that has an onset potential of ~1.43V. Few of the perovskites were also evaluated for their oxygen reduction activity (ORR) implying that these materials can be used as bi-functional catalysts.
M.S. in Chemical Engineering, July 2016
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Title: Heat treatment of chrome tungsten high speed tool steels
Creator: Perlstein, Harris, Lesser, David Barnes
Date: 2009, 1914
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/heattreatmentofc00perl
Thesis (B.S.)--Armour Institute of Technology

Title: Heat transmission in condenser coils
Creator: Anderson, W. J., Judson, L. D.
Date: 2009, 1921
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/heattransmission00ande
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 33

Title: Heat transmission in a vacuum evaporator
Creator: Dormitzer, H. C., Roleson, E. P.
Date: 2009, 1912
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/heattransmission00dorm
Thesis (B.S.)--Armour Institute of Technology

Title: Thermoelectric Power Systems and the Energy-Water Nexus
Creator: Walker, Michael Edward
Date: 2012-04-26, 2012-05
Description: The goal of this Thesis is the development of a comprehensive methodology to evaluate the total cost of water use in the recirculating cooling...
Show moreThe goal of this Thesis is the development of a comprehensive methodology to evaluate the total cost of water use in the recirculating cooling loops of thermoelectric power plants. This methodology expands upon the work presented in the literature to improve estimations of the economic impact of condenser fouling. The methods developed in this Thesis are incorporated into a user friendly Combined Cost Model (CCM) interface that will allow future researchers, students and plant personnel to perform the same comparative analyses presented herein. The objective of this Thesis is the application of the CCM to determine the economic viability of treated municipal wastewater (MWW) use to replace freshwater for cooling in power plants with recirculating cooling systems. To accomplish this objective, a set of case study evaluations are included to (1) evaluate the sensitivity of the economic impact of fouling to condenser design and operation, (2) determine the cost of treated MWW use in pulverized coal power plants, and (3) compare the relative cost of degraded water use in advanced power systems such as IGCC and oxy-combustion. The results of these evaluations show that current freshwater prices do not provide an economic incentive to switch to the use of treated MWW water. However, results indicate that the breakeven differential price of freshwater, at which the total costs of using freshwater and treated MWW are equal, is only 0.52 $/1000Gal. (USD 2009). In addition, the use of treated MWW for cooling is shown to be a better economic alternative to dry air cooling technology (DACT) for the conservation of freshwater resources. Cost-to-conservation estimates of treated MWW use are 1.1 $/1000 Gal., in contrast to 5.6 $/1000 Gal. for DACT. This Thesis also presents a novel, hybrid coal conversion concept, the dry gasification oxy-combustion (DGOC) power cycle. This process is similar to oxycombustion, in that it maintains a concentrated CO2 flue stream and does not utilize a complex separation step. However, coal conversion and sulfur removal are performed within a gasification unit. It is estimated to achieve CCS goals with a higher efficiency than the leading alternative strategies.
Ph.D. in Chemical Engineering, May 2012
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Title: EXTENSIONAL RHEOLOGY OF POLYISOBUTYLENE MELTS USING A COUNTER-ROTATING CYLINDERS RHEOMETER
Creator: Sun, David
Date: 2011-12-05, 2011-12
Description: Extensional rheology plays an immense role in many polymer processing operations, such as blow molding and fiber spinning. Extensional flow is...
Show moreExtensional rheology plays an immense role in many polymer processing operations, such as blow molding and fiber spinning. Extensional flow is a type of deformation that stretches a material and is sensitive to a polymer’s molecular structure. Elongational experiments are important in establishing flow models and verifying constitutive equations. Reliable extensional measurements and understanding of extensional rheology are vital for both academia and industry because they build upon the foundation for future theories, models, and applications. This study aims to understand the characteristics of a uniaxial elongation measuring technique and the validity of the data obtained. It focuses on the experimental properties of the Sentmanat Extensional Rheometer (SER), a specific uniaxial elongation rheometer, and tests the rheology for different molecular weights of polyisobutylene (PIB) melts. Through use of oscillatory shear, storage and loss modulus data are obtained and used to establish linear viscoelastic behavior. Using the SER, polyisobutylene was deformed to generate extensional viscosity data for different sample sizes, which was compared to the linear viscoelastic curve to check for consistency. Visual data analysis was used to examine deviations from ideal deformation. The results from this study were consistent with deviations seen by other researchers using the SER, and established experimental parameters that can improve performance of the SER. Based on elongational viscosity data, it is concluded that elongational viscosity does have a dependence based on sample size. In addition, this paper also quantifies the onset of surface instabilities, a phenomenon commonly seen, but not specifically reported. By utilizing the SER and different optical techniques, the development of the surface instability is examined. Analysis of the images demonstrates an appearance of surface striations that are consistent with different experimental parameters. By accurately capturing surface instabilities, they are found to be closely associated with sample deformations and onset of sample failure. By comparing visual and scattering images, the hencky strain (εinstability) at which instability occurs is consistently seen around 0.6 to 1.0. It is concluded that these striations are independent of strain rate, molecular weight, sample size, and technique. The validation of extensional viscosity’s dependence on sample size and onset of instability has great significance for uniaxial extension measuring tools, polymer processing, and extensional polymer modeling and simulation.
M.S. in Chemical Engineering, December 2011
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Title: ANISOTROPIC MICROSRHEOLOGY OF SELF-ASSEMBLING COLLAGEN NETWORKS
Creator: Dutov, Pavel
Date: 2015, 2015-05
Description: Collagen is the main component of human connective tissue and extracellular matrix. Here we report multiple novel methods for utilizing...
Show moreCollagen is the main component of human connective tissue and extracellular matrix. Here we report multiple novel methods for utilizing optical tweezers to measure mechanical properties of different hierarchical levels of collagenous materials. First, we introduce a method for optical trap calibration that is suitable for viscoelastic material. The method is designed for use on experimental setups with two optical tweezers and is based on pulling a trapped particle with one trap while holding it with the other. The method combines advantages of commonly known PSD-fitting and fast-sweeping methods, allowing calibration of a completely fixed trap in a fluid of unknown viscosity/viscoelasticity without additional expensive equipment. Then we report an approach to measure the longitudinal component of the elastic moduli of biological fibers under conditions close to those found in vivo and apply it to type I collagen from rat tail tendon. This approach combines optical tweezers, atomic force microscopy, and exploits Euler-Bernoulli elasticity theory for data analysis. The approach also avoids the traditional drying-soaking cycle, since samples are freshly extracted. Importantly, strains are kept below 0.5%, which appear consistent with the linear elastic regime. We find, surprisingly, that the longitudinal elastic modulus of type I collagen cannot be represented by a single quantity but rather is a distribution that is broader than the uncertainty of our experimental technique. Lastly, we report a new method for characterizing anisotropic viscoelastic response of collagenous matrices. Anisotropic collagenous extracellular matrices are used in biomedicine to enhance the wound healing process by directing fibroblast proliferation. We utilize an optical trap to monitor the thermal fluctuations of microspheres embedded into collagenous network to extract a viscoelastic response function of the network along the principal axes of anisotropy.
Ph.D. in Chemical Engineering, May 2015
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Title: The production of magnesium by the electrolysis of the fused salts
Creator: Grossman, Alexander N
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/productionofmagn00gros
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 1-21

Title: The production of potassium chloride and iodine from sea weed
Creator: Green, G. Vernon, Johnson, Harold S
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/productionofpota00gree
Thesis (B.S.)--Armour Institute of Technology

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