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Characterization Of Rock/Fluids Interactions At Reservoir Conditions, Dayanand Saini 2010 Louisiana State University and Agricultural and Mechanical College

Characterization Of Rock/Fluids Interactions At Reservoir Conditions, Dayanand Saini

LSU Doctoral Dissertations

In this study, interfacial phenomena of spreading, wettability, and rock/oil adhesion interactions in complex rock/oil/water systems were characterized at reservoir conditions of elevated pressures and temperatures. Capabilities of both ambient and reservoir condition optical cells were used for measuring the oil/water interfacial tension and dynamic (the water-receding and the water-advancing) contact angles for various complex rock/oil/water systems. Well known sessile oil drop volume alteration method was successfully used in this study for evaluating the applicability of the modified Young’s equation for characterizing the line tension in complex rock/oil/water systems at reservoir ...


Experimental Study On Single Cement Fracture Exposed To Co2 Saturated Brine Under Dynamic Conditions, Tevfik Yalcinkaya 2010 Louisiana State University and Agricultural and Mechanical College

Experimental Study On Single Cement Fracture Exposed To Co2 Saturated Brine Under Dynamic Conditions, Tevfik Yalcinkaya

LSU Master's Theses

Carbon capture and storage is one of the technologies that could help reduce CO2 concentration in the atmosphere while contributing to cutback of Greenhouse Gas emissions. Depleted oil and gas fields are favorable targets for CO2 storage because existing wells can be readily used as injection wells. However, a number of abandoned wells also serve as gateway to the reservoir which should be considered in the context of effective Carbon capture and storage. Wellbore cement is a very essential element in wellbore systems that serve as a barrier between different zones in the subsurface. The fractures inside wellbore cement sheath ...


Electrodeposited Cu-Based Catalysts For Alcohols From Co Hydrogenation And Electrodeposition Of Cuniw/Cuni Multilayered Alloys, Mayank Gupta 2010 Louisiana State University and Agricultural and Mechanical College

Electrodeposited Cu-Based Catalysts For Alcohols From Co Hydrogenation And Electrodeposition Of Cuniw/Cuni Multilayered Alloys, Mayank Gupta

LSU Doctoral Dissertations

Ethanol and higher alcohols can be used as a fuel or fuel additive in gasoline engines as well as a hydrogen carrier. One of the promising methods to synthesize these alcohols is based on thermochemical conversion of CO and H2 (CO hydrogenation). Conventional catalysts used for the conversion CO and H2 (syngas) to ethanol typically give yields less than 20% with the balance resulting mostly in the formation of the thermodynamically favored products CH4 and CO2. New catalysts with compositions designed to kinetically favor the formation of ethanol and higher alcohols are needed. Electrodeposition of nanowires offers a means to ...


Identifying Multiple Steady States In The Design Of Reactive Distillation Processes, Thomas Karl Mills 2010 Missouri University of Science and Technology

Identifying Multiple Steady States In The Design Of Reactive Distillation Processes, Thomas Karl Mills

Doctoral Dissertations

"Global homotopy continuation is used to identify multiple steady states in ideal reactive flash and reactive distillation systems involving a reaction of the form A+B [symbol for <--> C taking place in the liquid phase. The choice of specifications has an influence on the existence of multiple solutions for both the flash and the column. For the flash, specification of the heat input or withdrawal can give rise to multiplicities while specification of the split fraction does not. Specification of one internal energy balance variable and one external material balance variable does not produce multiplicities in the column; however, specification ...


The Functionalization Of Single Wall Carbon Nanotubes For Bioapplications, Pu Zhang 2010 Missouri University of Science and Technology

The Functionalization Of Single Wall Carbon Nanotubes For Bioapplications, Pu Zhang

Doctoral Dissertations

"In the past few years, the functionalization of carbon nanotubes has received considerable attention due to their extraordinary mechanical, electrical, optical and thermal properties. Using single wall carbon nanotube as a platform in bioanalytical and biomedical applications has also been extensively studied. This dissertation consists of four papers. In the first paper, various methods to functionalize single wall carbon nanotubes with immobilized enzyme for bioanalytical application were investigated. It was found that the covalent functionalization method was not an ideal methodology for enzyme addition neither in terms of enzyme loading amount nor activity retention compared to other methods. Use of ...


Sulfated Zirconia Modified Sba-15 Catalysts For Cellobiose Hydrolysis, Volkan Degirmenci, Deniz Uner, Basak Cinlar, Brent H. Shanks, Aysen Yilmaz, Rutget A. van Santen, Emiel J. M. Hensen 2010 Middle East Technical University

Sulfated Zirconia Modified Sba-15 Catalysts For Cellobiose Hydrolysis, Volkan Degirmenci, Deniz Uner, Basak Cinlar, Brent H. Shanks, Aysen Yilmaz, Rutget A. Van Santen, Emiel J. M. Hensen

Chemical and Biological Engineering Publications

Zirconia modified SBA-15 becomes a very active catalyst for the selective hydrolysis of cellobiose to glucose after sulfation. Spectroscopic investigations indicate the presence of Brønsted acid sites with similar properties to those present in conventional sulfated zirconia. Indications are found that the sulfate groups attached to zirconia interact with silanol groups of SBA-15. The catalytic activity in cellobiose hydrolysis correlates well with results for temperature-programmed decomposition of i-propylamine for a range of sulfated ZrO2/SBA-15 catalysts. A glucose yield of 60% during cellobiose hydrolysis at a reaction time of 90 min at 160° C is obtained.


Conversion Of Biorenewable Feedstocks: New Challenges In Heterogeneous Catalysis, Brent H. Shanks 2010 Iowa State University

Conversion Of Biorenewable Feedstocks: New Challenges In Heterogeneous Catalysis, Brent H. Shanks

Chemical and Biological Engineering Publications

For biorenewable feedstocks to serve as a significant source of chemicals and/or fuels, the development of new chemical processes as well as biological processes will be required. However, the conversion of biorenewable feedstocks with heterogeneous catalyst-based processes provides new challenges in inorganic catalyst research and development relative to historical work with petrochemical feedstocks. These catalyst and process challenges include the need to convert highly functionalized molecules with high selectivity, to develop stable catalytic liquid-solid interfaces in which the liquid phase is commonly aqueous, to control solvent phase effects and to develop novel reaction systems. While some of these challenges ...


Metabolic Analysis Of Wild-Type Escherichia Coli And A Pyruvate Dehydrogenase Complex (Pdhc)-Deficient Derivative Reveals The Role Of Pdhc In The Fermentative Metabolism Of Glucose, Abhishek Murarka, James M. Clomburg, Sean Moran, Jacqueline V. Shanks, Ramon Gonzalez 2010 Rice University

Metabolic Analysis Of Wild-Type Escherichia Coli And A Pyruvate Dehydrogenase Complex (Pdhc)-Deficient Derivative Reveals The Role Of Pdhc In The Fermentative Metabolism Of Glucose, Abhishek Murarka, James M. Clomburg, Sean Moran, Jacqueline V. Shanks, Ramon Gonzalez

Chemical and Biological Engineering Publications

Pyruvate is located at a metabolic junction of assimilatory and dissimilatory pathways and represents a switch point between respiratory and fermentative metabolism. In Escherichia coli, the pyruvate dehydrogenase complex (PDHC) and pyruvate formate-lyase are considered the primary routes of pyruvate conversion to acetyl-CoA for aerobic respiration and anaerobic fermentation, respectively. During glucose fermentation, the in vivo activity of PDHC has been reported as either very low or undetectable, and the role of this enzyme remains unknown. In this study, a comprehensive characterization of wild-type E. coli MG1655 and a PDHC-deficient derivative (Pdh) led to the identification of the role of ...


Quadrature-Based Moment Model For Moderately Dense Polydisperse Gas-Particle Flows, Rodney O. Fox, Prakash Vedula 2010 Iowa State University

Quadrature-Based Moment Model For Moderately Dense Polydisperse Gas-Particle Flows, Rodney O. Fox, Prakash Vedula

Chemical and Biological Engineering Publications

A quadrature-based moment model is derived for moderately dense polydisperse gas-particle flows starting from the inelastic Boltzmann-Enskog kinetic equation including terms for particle acceleration (e.g., gravity and fluid drag). The derivation is carried out for the joint number density function, f(t,x,m,u), of particle mass and velocity, and thus, the model can describe the transport of polydisperse particles with size and density differences. The transport equations for the integer moments of the velocity distribution function are derived in exact form for all values of the coefficient of restitution for particle-particle collisions. For particular limiting cases, the ...


Utilizing Protein-Lean Coproducts From Corn Containing Recombinant Pharmaceutical Proteins For Ethanol Production, Ilankovan Paraman, Lorena Beatriz Moeller, M. Paul Scott, Kan Wang, Charles E. Glatz, Lawrence A. Johnson 2010 Iowa State University

Utilizing Protein-Lean Coproducts From Corn Containing Recombinant Pharmaceutical Proteins For Ethanol Production, Ilankovan Paraman, Lorena Beatriz Moeller, M. Paul Scott, Kan Wang, Charles E. Glatz, Lawrence A. Johnson

Chemical and Biological Engineering Publications

Protein-lean fractions of corn (maize) containing recombinant (r) pharmaceutical proteins were evaluated as a potential feedstock to produce fuel ethanol. The levels of residual r-proteins in the coproduct, distillers dry grains with solubles (DDGS), were determined. Transgenic corn lines containing recombinant green fluorescence protein (r-GFP) and a recombinant subunit vaccine of Escherichia coli enterotoxin (r-LTB), primarily expressed in endosperm, and another two corn lines containing recombinant human collagen (r-CIα1) andr-GFP, primarily expressed in germ, were used as model systems. The kernels were either ground and used for fermentation or dry fractionated to recover germ-rich ...


Optimization Of Parameters And Study Of Kinetics In Lactulose Production By Lactose Isomerization Using Strong Basic Anion Exchange Resin, Arvind Nanduri 2010 Missouri University of Science and Technology

Optimization Of Parameters And Study Of Kinetics In Lactulose Production By Lactose Isomerization Using Strong Basic Anion Exchange Resin, Arvind Nanduri

Masters Theses

"In this work, an experimental design was employed to investigate the effects of different operating conditions on the isomerization of lactose to lactulose by using strong basic anion exchange resin (AMBERLITE-IRA 402). Temperature, resin/lactose mass ratio and pH were considered to be the three factors affecting the conversion of lactose. Box-Behnken design was then used to optimize the operating conditions for maximum response and also to study the various interaction and main effects of the factors. The analysis of variance (ANOVA) of the experimental data showed a high correlation coefficient R² (0.99) and a low root mean square ...


Enhanced Photorefractivity In A Polymeric Composite Photosensitized With Modified Carbon Nanotubes, Naveen Kumar Lingam 2010 Missouri University of Science and Technology

Enhanced Photorefractivity In A Polymeric Composite Photosensitized With Modified Carbon Nanotubes, Naveen Kumar Lingam

Masters Theses

"This work involves the photosensitization of photorefractive polymeric composites through the inclusion of multiwalled and singlewalled carbon nanotubes grafted to poly(N-vinyl carbazole). The photorefractive nature of the holograms gratings was established using two-beam-coupling, yielding two-beam-coupling gain coefficients approaching 80 cm⁻¹. Degenerate-four-wave-mixing experiments exhibited diffraction efficiencies as high as 60% as well as over-modulation voltages as low as ~ 40 V/µm. These notable figures of merit indicate that the grafting of the various carbon nanotubes to the poly(N-vinyl carbazole) polymer resulted in enhanced photorefractive performance. The mechanism responsible for this enhancement in photorefractive performance is investigated using a ...


Biodiesel Production Using Supercritical Methanol, Dhaval Nitin Modi 2010 Missouri University of Science and Technology

Biodiesel Production Using Supercritical Methanol, Dhaval Nitin Modi

Masters Theses

"The catalyst-free transesterification of oil (triglycerides) in supercritical methanol at a temperature and pressure above 239⁰C and 8.1MPa, respectively, provides a new way of producing biodiesel. High reaction temperature and pressure help to accelerate the transesterification because the supercritical methanol becomes non-polar and has enhanced contact with oil. The supercritical transesterification of soybean oil was carried out in a 170 ml volume high-pressure batch reactor. The pressure within the batch reactor was self-generated from heating the contents since no pumps were used. Transesterification of soybean oil with supercritical methanol readily produced biodiesel. Since the supercritical transesterification is carried out ...


A Comrehensive Model Study For Flash Nanoprecipitation: Computational Fluid Dynamics, Micro- Particle Image Velocimetry, And Population Balance Modeling, Janine Chungyin Cheng 2010 Iowa State University

A Comrehensive Model Study For Flash Nanoprecipitation: Computational Fluid Dynamics, Micro- Particle Image Velocimetry, And Population Balance Modeling, Janine Chungyin Cheng

Graduate Theses and Dissertations

A model study has been conducted for Flash Nanoprecipitation(FNP)) - a novel approach to produce functional nanoparticles. A mixing study has been conducted in a custom-designed microscale multi-inlet vortex reactor (MIVR) and a scalar mixing model was validated against experimental data. A microPIV experiment was conducted to further validate the turbulent model. A population balance equation (PBE) has been proposed to model the FNP process. It was furthermore, integrated into a computational fluid dynamics (CFD) simulation of to yield conditions comparable to the real experimental settings. In coping with the complicated aggregation model in the CFD code, a new numerical ...


Development Of A Sorbent For Carbon Dioxide, Dursun Can Ozcan 2010 Iowa State University

Development Of A Sorbent For Carbon Dioxide, Dursun Can Ozcan

Graduate Theses and Dissertations

The reversible absorption of CO2 by CaO at high temperature is a promising method for capturing and removing CO2 from a hot gas stream. The main challenge facing the use of this method is the deterioration of CO2 absorption capacity when the method is applied over a large number of CO2 absorption/desorption cycles. Although various techniques have been proposed for improving the cyclic stability and performance of calcium based sorbents, a cost effective method is still needed for industrial applications. Therefore, two promising methods for improving the cyclic stability were selected for further investigation. One method is to optimize ...


Structures, Kinetics, And Modeling Of Glycoside Hydrolase Family 44 Endoglucanases From Clostridium Acetobutylicum And Ruminococcus Flavefaciens Fd-1, Christopher Donald Warner 2010 Iowa State University

Structures, Kinetics, And Modeling Of Glycoside Hydrolase Family 44 Endoglucanases From Clostridium Acetobutylicum And Ruminococcus Flavefaciens Fd-1, Christopher Donald Warner

Graduate Theses and Dissertations

Glycoside hydrolases (GH) are enzymes that hydrolyze glycosidic bonds between carbohydrates. Family 44 contains endo- and xylo- glucanases capable of hydrolyzing cellulose and hemicelluose. Two members produced by Clostridium acetobutylicum and Ruminococcus flavefaciens FD-1 are the subjects of characterization work in this dissertation.

The EG from Clostridium acetobutylicum was characterized both structurally and kinetically. Crystallization and x-ray diffraction to 2.2-y resolution revealed a TIM barrel-like structure with additional ψ-loop and β-sandwich folds. The EG hydrolyzes cellotetraose and larger cellooligosaccharides, as well as carboxymethylcellulose and xylan at approximately the same rates. It converts lichenan to oligosaccharides of intermediate size and ...


Membrane-Based Separations For Solid/Liquid Clarification And Protein Purification, Matthew Thomas Aspelund 2010 Iowa State University

Membrane-Based Separations For Solid/Liquid Clarification And Protein Purification, Matthew Thomas Aspelund

Graduate Theses and Dissertations

Recombinant protein technology has become increasingly important in recent years. Recombinant proteins can be found in everything from pharmaceuticals to detergents. The increasing demand and the high cost associated with the production and purification of recombinant proteins highlights the need to develop efficient and inexpensive methods for the solid/liquid clarification and purification of these proteins. Membrane technologies, which offer the advantage of high throughput and ever-improving selectivity, have the potential to meet the increased demands placed on the downstream processing of recombinant proteins. The overall objective of this work was to develop methods for the solid/liquid clarification and ...


Molecular Design Of Nanoparticle-Based Delivery Vehicles For Pneumonic Plague, Bret Daniel Ulery 2010 Iowa State University

Molecular Design Of Nanoparticle-Based Delivery Vehicles For Pneumonic Plague, Bret Daniel Ulery

Graduate Theses and Dissertations

The work described in this dissertation focuses on the design of polyanhydride nanoparticles that function as both adjuvants and long-term antigen delivery vehicles in order to improve vaccination, specifically for biodefense-related applications. Chapter 1 is an introduction into the threat of bioterrorism, polymer-based controlled delivery systems and challenges associated with vaccine design.

Chapter 2 is a detailed literature review of topics related to the research conducted in this dissertation. Areas covered include basic immunology, vaccine design, degradable polymer-based adjuvant engineering, plague (Yersinia pestis) biology, and vaccines that confer protection against plague.

Chapter 3 overviews the research objectives and the specific ...


Hierarchically Ordered Montmorillonite Block Copolymer Brushes, Ross Eric Behling 2010 Iowa State University

Hierarchically Ordered Montmorillonite Block Copolymer Brushes, Ross Eric Behling

Graduate Theses and Dissertations

We report the phase behavior of a new class of polymer

nanocomposites, montmorillonite (MMT) block copolymer brushes

(MBBs). MBBs are comprised of discrete MMT particles encapsulated with block copolymer brushes synthesized via surface initiated atom transfer radical polymerization. Polystyrene-b-poly(n-butyl acrylate) MBBs of varying composition and total Mn = 80--250 kDa were compared with bulk block copolymers via electron

microscopy and a host of mechanical tests. MBBs were found to self

assemble into single grain morphologies across incredibly large

areas (> 3 um). Perhaps most promising is that MBBs maintain

similar melt state properties to bulk block copolymers and are thus

amenable ...


Catalytic Strategies Of Glycoside Hydrolases, Luis Petersen 2010 Iowa State University

Catalytic Strategies Of Glycoside Hydrolases, Luis Petersen

Graduate Theses and Dissertations

Glycoside hydrolases (GHs) are enzymes that catalyze the hydrolysis of the glycosidic bond between two carbohydrate residues or a carbohydrate unit linked to a non-carbohydrate aglycon unit. Despite years of research dedicated to GHs, there are still several mechanistic details, relevant for individual GH enzymes, that remain to be investigated. In this work, a computational analysis of the detailed mechanism of several GHs is presented. QM/MM metadynamics simulations of two glycoside hydrolases, GH8 endoglucanase and GH43 β-xylosidase, give insight into the enzymatic deconstruction of the plant cell wall, and the detailed reaction mechanism of both enzymes. In addition, an ...


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