Chemical Engineering Commons^™

A Fractal Analysis Of The Detection Of Glucose Molecules On Biosensor Surfaces, Lokesh Taneja

Electronic Theses and Dissertations

A fractal analysis for the binding and dissociation of glucose molecules to different biosensor surfaces is presented. The sensors contain immobilized glucose oxidase enzymes that have an affinity for the glucose molecules in solution. Data for different modified biosensors is modeled and analyzed, and a single, dual or triple-fractal analysis is applied where adequate. The binding and dissociation kinetics coefficient where applicable are calculated for each of models along with the fractal dimensions. When both binding and dissociation phases are present, the affinity, K of the receptor to the glucose molecule is calculated and its variation with the fractal dimension …

Thermal And Photochemical Interaction Of Co2 With Biochar, Eneruvie Uyoyou Okinedo

Electronic Theses and Dissertations

With interest in the changes that may occur to the carbonaceous portion of biochar obtain through the pyrolysis of biomass, the simple interaction between CO2 and biochar with water or a mixture of water and ethanol as hydrogen donor resulted in three significant observations. These reactions were carried out thermally at 333K and photochemically by simulating energy from the with a xenon lamp. The photochemical reaction involving biochar, CO2 with water or a mixture of water and ethanol as hydrogen donor led to a decrease in oxygen content of the parent biochar material, as observed by an increase in the …

Effect Of Hole Spacing On Deposition Of Fine Coal Flyash Near Film Cooling Holes, Weiguo Ai, Nathan Murray, Thomas H. Fletcher, Spencer Harding, Elizabeth Bonsignore, Jeffrey P. Bons

Faculty Publications

Particulate deposition experiments were performed in a turbine accelerated deposition facility to examine the nature of flyash deposits near film cooling holes. Deposition on both bare metal and thermal barrier coating (TBC) coupons was studied, with hole spacing (s/d) of 2.25, 3.375, and 4.5. Sub-bituminous coal ash particles (mass mean diameter of 13 microns) were accelerated to a combustor exit flow Mach number of 0.25 and heated to 1183°C before impinging on a target coupon. The particle loading in the 1 h tests was 310 ppmw. Blowing ratios were varied in these experiments from 0 to 4.0 with the density …

Computational Analysis Of Conjugate Heat Transfer And Particulate Deposition On A High Pressure Turbine Vane, Weiguo Ai, Thomas H. Fletcher

Faculty Publications

Numerical computations were conducted to simulate flash deposition experiments on gas turbine disk samples with internal impingement and film cooling using a computational fluid dynamics (CFD) code (FLUENT). The standard k-epsilon turbulence model and Reynoldsaveraged Navier–Stokes were employed to compute the flow field and heat transfer. The boundary conditions were specified to be in agreement with the conditions measured in experiments performed in the BYU turbine accelerated deposition facility (TADF). A Lagrangian particle method was utilized to predict the ash particulate deposition. Userdefined subroutines were linked with FLUENT to build the deposition model. The model includes particle sticking/rebounding and particle …

Design Mixers To Minimize Effects Of Erosion And Corrosion Erosion, Julian B. Fasano, Eric E. Janz, Kevin J. Myers

Chemical and Materials Engineering Faculty Publications

A thorough review of the major parameters that affect solid-liquid slurry wear on impellers and techniques for minimizing wear is presented. These major parameters include (i) chemical environment, (ii) hardness of solids, (iii) density of solids, (iv) percent solids, (v) shape of solids, (vi) fluid regime (turbulent, transitional, or laminar), (vii) hardness of the mixer's wetted parts, (viii) hydraulic efficiency of the impeller (kinetic energy dissipation rates near the impeller blades), (ix) impact velocity, and (x) impact frequency. Techniques for minimizing the wear on impellers cover the choice of impeller, size and speed of the impeller, alloy selection, and surface …

A Review Of Some Subtleties Of Practical Relevance, Keqin Gu

SIUE Faculty Research, Scholarship, and Creative Activity

This paper reviews some subtleties in time-delay systems of neutral type that are believed to be of particular relevance in practice. Both traditional formulation and the coupled differential-difference equation formulation are used. The discontinuity of the spectrum as a function of delays is discussed. Conditions to guarantee stability under small parameter variations are given. A number of subjects that have been discussed in the literature, often using different methods, are reviewed to illustrate some fundamental concepts. These include systems with small delays, the sensitivity of Smith predictor to small delay mismatch, and the discrete implementation of distributed-delay feedback control. The …

Admicellar Polymerization Of Calcium Carbonate And Its Performance In Drilling Fluids, Poh Lee Cheah

Electronic Theses and Dissertations

Admicellar polymerization using sodium dodecylsulfate (SDS) template to form ultrafilm polystyrene on commercial calcium carbonate (CaCO3 ) of various particle sizes was studied. Adsorption isotherms of SDS decrease after the critical micelle concentration (CMC) of SDS was observed. This is explained by the phase behavior of SDS with calcium ion. The solubility product constants (Ksp) for calcium dodecylsulfate (Ca(DS) 2) were calculated as 1.55x10?9M3 at 30°C and 8.58x10?9M3 at 50°C. At SDS concentrations above the CMC, precipitation of Ca(DS)2 was governed by the critical ratio of calcium ion concentration bound onto anionic micelles which was 0.22 at 30°C and 0.20 …

Heat Transfer Enhancement In A Straight Channel Via A Rotationally Oscillating Adiabatic Cylinder, Ali Beskok, Mehrdad Raisee, Bayram Celik, Bedri Yagiz, Mohsen Cheraghi

Mechanical & Aerospace Engineering Faculty Publications

Heat convection from the uniformly heated walls of a straight channel in presence of a rotationally oscillating cylinder (ROC) is simulated at Re = 100. Heat transfer enhancement due to vortex shedding from the ROC is investigated. Systematic studies are performed to explore the rotation angle and frequency influences on heat transfer by varying the latter in range of the lock-in regime and the former from 0 to 2 π/3. All simulation results are based on the numerical solutions of two-dimensional, unsteady, incompressible Navier-Stokes and energy equations using an h/p type finite element algorithm. Considering time periodicity of the resulting …

Quantifying Cell-To-Cell Variations In Lithium Ion Batteries, Shriram Santhanagopalan, Ralph E. White

Faculty Publications

Lithium ion batteries have conventionally been manufactured in small capacities but large volumes for consumer electronics applications. More recently, the industry has seen a surge in the individual cell capacities, as well as the number of cells used to build modules and packs. Reducing cell-to-cell and lot-to-lot variations has been identified as one of the major means to reduce the rejection rate when building the packs as well as to improve pack durability. The tight quality control measures have been passed on from the pack manufactures to the companies building the individual cells and in turn to the components. This …

Functionalized Silica Materials And Mixed-Matrix Membranes For Environmental Applications, Noah Daniel Meeks

Theses and Dissertations--Chemical and Materials Engineering

Functionalized silica materials are synthesized for various environmental applications. The overall objective is functionalization with sulfur-containing moieties for mercury sorption and as a platform for nanoparticle synthesis. The first objective is quantifying this functionalization for various silica platforms. The second objective is development of effective mercury sorbents, for both aqueous mercury and elemental mercury vapor. Third, those sorbents are incorporated into mixed matrix membranes (MMM) for aqueous mercury sorption. Fourth, functionalized silica materials are developed as platforms for the synthesis of reactive metal nanoparticles (NP) for the degradation of trichloroethylene.

Thiol-functionalized silica is used as a sorbent for aqueous mercury, …

Development Of Strategies To Minimize The Release Of Trace Elements From Coal Waste Sources, Mohammad Rezaee

Theses and Dissertations--Mining Engineering

To assess strategies aimed at minimizing the release of trace elements and the impact of disposal of coal waste materials on the environment, two long-term leaching experiments of up to five months duration were performed using waste materials from two plants cleaning high and low sulfur bituminous coal. The tests evaluated the mobility of major trace elements under different disposal scenarios: (i) a static leaching test designed to simulate the quiescent conditions encountered by coal waste material stored under water in a stable impoundment, and (ii) a dynamic test to simulate waste materials exposed to the atmosphere, either in variable …

Development Of Tailor-Designed Gold-Platinum Nanoparticles Binary Catalysts For Efficient Formic Acid Electrooxidation, Islam M. Al-Akraa Dr, Ahmad M. Mohammad Prof, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof

Chemical Engineering

The modification of a glassy carbon (GC) electrode with platinum (PtNPs) and gold (AuNPs) nanoparticles is targeted to fabricate efficient anodes for the electrooxidation of formic acid (FA). A proper adjustment of the deposition sequence of PtNPs and AuNPs could eventually enhance the electrocatalytic activity of the electrode in such a way that suppresses the CO poisoning effect during FA oxidation. The highest catalytic activity is obtained at the Au/Pt/GC electrode (with PtNPs firstly deposited on the GC electrode followed by AuNPs). This superb enhancement is quantified by comparing the relative ratio of the direct vs. the indirect oxidation peaks …

Differential Gene Expression In A Louisiana Strain Of Microalgae, John Joseph Tate

LSU Master's Theses

Considerable interest in alternative energy has stimulated research in biofuels, particularly microalgal biofuels. In particular, strains of algae that accumulate lipids to be used for biofuels must be adapted to outdoor growth and resistant to invasive species. Differential gene expression in a Louisiana algae/cyanobacteria co-culture consisting of approximately 97% Chlorella vulgaris and 3% Leptolyngbya sp. possessing these traits was examined. Possible reasons for the enhanced growth of the co-culture relative to a Chlorella monoculture were reviewed, including cyanobacterial symbiosis and chemicals produced by cyanobacteria or bacteria that could influence the growth of Chlorella. The co-culture and Chlorella monoculture were cultivated …

Experimental Investigations In Co2 Sequestration And Shale Caprock Integrity, Abiola Olukola Olabode

LSU Master's Theses

More than sixty percent (60%) of conventional hydrocarbon reservoirs which are potential CO2 repositories are sealed by tight shale caprock. The geochemical reactivity of shale caprock during CO2 diffusive transport needs to be included in the reservoir characterization of potential CO2 sequestration sites as slow reactive transport processes can either strengthen or degrade seal integrity over the long term. Several simulation results had predicted that influx-induced mineral dissolution/precipitation reactions within shale caprocks can continuously reduce micro-fracture networks, while pressure and effective-stress transformation first rapidly increase then progressively constrict them. This experimental work applied specific analytical techniques in investigating changes in …

Airlift Column Photobioreactors For Porphyridium Sp. Culturing: Part Ii. Verification Of Dynamic Growth Rate Model For Reactor Performance Evaluation, Hu Ping Luo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Dynamic Growth Rate Model Has Been Developed to Quantify the Impact of Hydrodynamics on the Growth of Photosynthetic Microorganisms and to Predict the Photobioreactor Performance. Rigorous Verification of Such Reactor Models, However, is Rare in the Literature. in This Part of Work, Verification of a Dynamic Growth Rate Model Developed in Luo and Al-Dahhan (2004) [Biotech Bioeng 85(4): 382-393.] Was Attempted using the Experimental Results Reported in Part I of This Work and Results from Literature. the Irradiance Distribution Inside the Studied Reactor Was Also Measured at Different Optical Densities and Successfully Correlated by the Lambert-Beer Law. When Reliable Hydrodynamic …

Kinetic Modeling Of Methanol Synthesis From Carbon Monoxide, Carbon Dioxide, And Hydrogen Over A Cu/Zno/Cr2o3 Catalyst, Daaniya Rahman

Master's Theses

The main purpose of this study was to investigate kinetic models proposed in the

literature for methanol synthesis and select the best fit model using regression techniques

in POLYMATH. Another aim was to use the results from the best fit model to explain

some aspects and resolve some questions related to methanol synthesis kinetics. Two

statistically sound kinetic models were chosen from literature based on their goodness of

fit to the respective kinetic data. POLYMATH, the non-linear regression software, was

used to fit published experimental data to different kinetic models and evaluate kinetic

parameters. The statistical results from POLYMATH were …

Risk Of Well Integrity Failure Due Sustained Casing Pressure, Koray Kinik

LSU Master's Theses

Sustained casing pressure (SCP) is considered a well integrity problem. The approach of this study is to look at SCP as environmental risk due hydrocarbon release. Currently, the risk is qualified by the value of surface pressure (Pcsg) that may cause failure of casing head. However, the resulting rate of gas emission to the atmosphere is not considered. Also not considered is a possibility of breaching the casing shoe due transmission of Pcsg downhole. The objective of this study is to develop methods for maximum possible air emission rates (MER) and risk of subsurface well integrity failure due SCP. Mathematical …

Experimental Study Of The Effect Of Drilling Fluid Contamination On The Integrity Of Cement-Formation Interface, Nnamdi Charles Agbasimalo

LSU Master's Theses

Well cementing is one of the key processes performed during drilling and completion of wells. The main objective of primary cementing is to provide zonal isolation. Failure of cement to provide zonal isolation can lead to contamination of fresh water aquifers, sustained casing pressure, or blowout. For effective cementing, the cement slurry should completely displace the drilling fluid. In practice, this is hard to achieve and some mud is left in the wellbore where it contaminates the cement after cement placement.

This study investigates the effect of mud contamination of cement on the integrity of cement-formation interface. Flow-through experiments were …

Double-Bond Isomerization Of Long Chain Olefins, James Edward Bruno

LSU Master's Theses

Bruno, James Edward, B.S., Western Michigan University, 2010 Master of Science, Fall Commencement, 2012 Major: Chemical Engineering Double-Bond Isomerization of Long Chain Olefins Thesis directed by Professor Kerry Dooley Pages in thesis, 54. Words in Abstract, 349. ABSTRACT Alkenyl Succinic Anhydride (ASA) is commonly used in the paper industry as a sizing agent. ASA is produced by reacting maleic anhydride with long-chain internal olefins. Such olefins are only available with the double bond in the terminal position, so an isomerization step is necessary. The isomerization can be catalyzed using solid strong acid catalysts, such as those containing sulfonic acid groups. …

Simulations Of The Primary Cement Placement In Annular Geometries During Well Completion Using Computational Fluid Dynamics (Cfd), Muhammad Zulqarnain

LSU Master's Theses

Effective zonal isolation during primary cementing is only possible when drilling mud in the annulus is completely displaced with cement, while the spacers aid in this process. During the displacement process the rheological properties of fluids used and the operating conditions control the motion of different fluids interfaces; desired stable interfacial displacement leads to piston like motion. Computational Fluid Dynamics (CFD) tool with the Volume-of-Fluid (VOF) has been validated against experimental and used to conduct numerical experiments in a virtual well model consisting of 50 ft vertical section of 8.765" x 12.5" annulus having initially mud and this mud is …

Catalytic Oxidative Desulfurization: A Comparison Of Reactors, Andrew Marshall Madrid

LSU Master's Theses

A novel technology, a pulsed oscillating monolith reactor (POMR), was compared to a standard autoclave reactor for oxidative desulfurization (ODS) of a model diesel fuel. Two classes of catalysts, mesoporous Ti-MCM-41 and Pd on carbon, were used for ODS. The oxidants used were O2 and peroxide. The model diesel compound was 75 wt% alkanes, 24 wt% alkylaromatic, 0.95 wt% sulfur heterocycles and 0.05% nitrogen heterocycles. ODS reactions were conducted from 343-423 K and pressures from 1.0-1.3 MPa O2. The only component that was not oxidized was the alkane. The POMR showed promise; there was up to a factor of 20 …

Design And Optimization Of 2.5 Dimension Porous Media Micromodel For Nanosensor Flow Experiments, Saade Alexis Bou-Mikael

LSU Master's Theses

Micromodels are used to visualize and study pore-scale phenomena such as immiscible displacements in porous media, foam flow behavior, and CO2 flooding. The understanding gained from these experiments can be used to develop models to predict future behavior of the reservoir. Most micromodels are constructed using lithography techniques that are restricted to 2D patterns that require artificial generation or manipulation of images to develop connected micromodels. Characteristics innate to the original rock structure are often lost or skewed in developing micromodels that bear little resemblance to the original media. Alternative microfabrication techniques using a micromilling tool have allowed us to …

Measurement Of Interfacial Tension In Hydrocarbon/Water/Dispersant Systems At Deepwater Conditions, Mohamed Abdelrahim

LSU Master's Theses

The events of the Deepwater Horizon oil spill in the Gulf of Mexico were associated with great water depths that made it difficult to understand the behavior of the spilled oil as it came in contact with the seawater. The remedial subsea application of chemical dispersants draws interest to evaluate the interfacial interactions between the oil and water at such great water depths. Most importantly, a quantification of the interfacial tension (IFT) between the spilled oil and seawater at deepwater conditions can provide insight into the effectiveness of the chemical dispersion of spilled oil. In this study, Macondo crude oil …

Novel Blends Of Sulfur-Tolerant Water-Gas Shift Catalysts For Biofuel Applications, Timothy Michael Roberge

USF Tampa Graduate Theses and Dissertations

As traditional sources of energy become depleted, significant research interest has gone into conversion of biomass into renewable fuels. Biomass-derived synthesis gas typically contains concentrations of approximately 30 to 600 ppm H2S in stream. H2S is a catalyst poison which adversely affects downstream processing of hydrogen for gas to liquid plants. The water-gas shift reaction is an integral part of converting CO and steam to H2 and CO2. Currently, all known water-gas shift catalysts deactivate in sulfur concentrations typical of biomass-derived synthesis gas. Novel catalysts are needed to remain active in the presence of sulfur concentrations in order to boost …

Catalytic Tri-Reforming Of Biomass-Derived Syngas To Produce Desired H2:Co Ratios For Fuel Applications, Devin Mason Walker

USF Tampa Graduate Theses and Dissertations

This study focuses on upgrading biomass derived syngas for the synthesis of liquid fuels using Fischer-Tropsch synthesis (FTS). The process includes novel gasification of biomass via a tri-reforming process which involves a synergetic combination of CO2 reforming, steam reforming, and partial oxidation of methane. Typical biomass-derived syngas H2:CO is 1:1 and contains tars that deactivate FT catalyst. This innovation allows for cost-effective one-step production of syngas in the required H2:CO of 2:1 with reduction of tars for use in the FTS. To maximize the performance of the tri-reforming catalyst, an attempt to control oxygen mobility, thermal stability, dispersion of metal, …

Smart Packaging: A Novel Technique For Localized Drug Delivery For Ovarian Cancer, Eva Christabel Williams

USF Tampa Graduate Theses and Dissertations

Localized drug delivery is emerging as an effective technique due to its ability to administer therapeutic concentrations and controlled release of drugs to cancer sites in the body. It also prevents the contact of harsh chemotherapy drugs to healthy regions in the body that otherwise would become exposed to current treatments.

This study reports on a model chemotherapy drug delivery system comprising non-ionic surfactant vesicles (niosomes) packaged within a temperature-sensitive chitosan network. This smart packaging, or package-within-a package system, provides two distinct advantages. First, the gel prevents circulation of the niosomes and maintains delivery in the vicinity of a tumor. …

Aggregation Of Sediment And Bacteria With Mucilage From The Opuntia Ficus-Indica Cactus, Audrey Lynn Buttice

USF Tampa Graduate Theses and Dissertations

Flocculants are commonly used in industrial settings where solid-liquid separations are desired including industrial and municipal wastewater management and potable water production facilities. Conventional flocculants include inorganic metal salts and synthetic organic polymers. The cost, availability, and harmful effects of the non-biodegradable nature of these flocculants have led to the widespread study of natural flocculants. Current natural flocculants being studied include polysaccharides cultivated from microbial extracellular matrix products and plant based materials. In this study, the mucilage of Opuntia ficus-indica cactus was evaluated as a natural flocculant for sediments and bacteria. The O. ficus-indica cactus is also known as the …

Precipitation Of Phosphate Minerals From Effluent Of Anaerobically Digested Swine Manure, Alex Y. Lin

USF Tampa Graduate Theses and Dissertations

Swine production represents approximately 40% of the world's meat production, and its wastes contain high concentrations of organic carbon, nitrogen (N), and phosphorus (P). Anaerobic digestion is an increasingly popular technology for treating animal wastes while simultaneously generating energy. Its propagation and ability to solubilize organic N and P make adding a struvite recovery process attractive. Recovering struvite (MgNH4PO4) from anaerobically digested swine waste can address global P shortages, meet P discharge guidelines, and produce slow-release fertilizer, which can be sold for revenue.

Anaerobic digesters were operated with at organic loading rates of 3.4-3.9 g volatile solids per liter per …

Design Of Colloidal Composite Catalysts For Co2 Photoreduction And For Co Oxidation, Bijith D. Mankidy

USF Tampa Graduate Theses and Dissertations

In this doctoral dissertation, novel colloidal routes were used to synthesize nanomaterials with unique features. We have studied the impact of nanoparticle size of catalyst, role of high surface area of a photocatalyst, and the effect of varying elemental composition of co-catalytic nanoparticles in combination with core-shell plasmonic nanoparticles. We have demonstrated how physical and chemical characteristics of nanomaterials with these unique features play a role in catalytic reactions, specifically the oxidation of CO and the photoreduction of CO2. The first objective of this doctoral dissertation involved the preparation of CoO nanoparticles with discrete nanoparticles sizes (1-14 nm) using a …

Applications Of Cfd Simulations On Microfluidic Systems For Nanoparticle Synthesis, Yuehao Li

LSU Master's Theses

Microfluidics has been extensively investigated as a unique platform to synthesize nanoparticles with desired properties, e.g., size and morphology. Compared to the conventional batch reactors, wet-chemical synthesis using continuous flow microfluidics provides better control over addition of reagents, heat and mass transfer, and reproducibility. Recently, millifluidics has emerged as an alternative since it offers similar control as microfluidics. With its dimensions scaled up to millimeter size, millifluidics saves fabrication efforts and potentially paves the way for industrial applications. Good designs and manipulations of microfluidic and millifluidic devices rely on solid understanding of fluid dynamics. Fluid flow plays an important role …