Engineering Commons^™

Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration, Caitlyn Cook

Materials Engineering

The top contact electrode layers of nine organic photovoltaic cells were prepared with two varying factors: three Silver nanowire (AgNW) densities deposited on a conductive polymer doped with three concentrations. Silver’s low sheet resistance of 20-Ω/sq is hypothesized to lower the sheet resistance of the anode layer and thus enhance the overall efficiency of the cell. Four-point probe measurements indicated that increasing AgNW density in the top contact electrode layer of an organic photovoltaic cell significantly reduces sheet resistance from 52.2k-Ω/sq to 18.0 Ω/sq. Although an increase in doping concentration of the conductive polymer reduced sheet resistance in low AgNW …

Computer Simulations Of Propulsion Of Self-Propelled Flexible Nanobody, Ye Luo

Masters Theses

Swimming bodies such as flagellum and fishes are found everywhere in liquid environment. The research of simulation of swimmers is one of the most important branches among the field of biophysics. This study focus on the direct computer simulation of self-propelled flexible nanobody in fluid field. Two new objectives is studied based on the previous research of Tai-hsien Wu and Dewei ai (2014)[1]. ln Wu's article, the front end of micro swimming body is fixed and the migration of swimmers is neglected. For a further study, one of new targets is to release the head in 3-D simulation fluid area. …

Measuring Performance Of Paint Coating Via Laboratory And Field Testing, Eugene Leung, Rocco Lattanzio

Materials Engineering

No abstract provided.

Synthesis Of Co-Electrospun Lead Selenide Nanostructures Within Anatase Titania Nanotubes For Advanced Photovoltaics, Evan K. Wujcik, Stephanie R. Aceto, David R. Heskett, Arijit Bose

Chemical, Biomolecular, and Materials Engineering Faculty Publications

Inorganic nano-scale heterostructures have many advantages over hybrid organic-inorganic dye-sensitized solar cells (DSSC or Grätzel cells), including their resistance to photo-bleaching, thermal stability, large specific surface areas, and general robustness. This study presents a first-of-its-kind low-cost all-inorganic lead selenide-anatase titania (PbSe/TiO₂) nanotube heterostructure material for photovoltaic applications. Herein, PbSe nanostructures have been co-electrospun within a hollow TiO2 nanotube with high connectivity for highly efficient charge carrier flow and electron-hole pair separation. This material has been characterized by transmission electron microscopy (TEM), electron diffraction, energy dispersive X-ray spectroscopy (EDX) to show the morphology and material composition of the synthesized …

Post-Installed Fiber Optic Pressure Sensors On Subsea Production Risers For Severe Slugging Control, Ammon Eaton, Seyed M. Safdarnejad, John Hedengren, Kristi Moffat, Casey Hubbell, David Brower, Alexis Brower

Faculty Publications

Fiber optic sensors have gained increasing use in monitoring offshore structures. The sensors have successfully monitored flowlines, umbilicals, wells, Tension Leg Platform (TLP) tendons, production and drilling risers, and mooring lines. Fiber optic sensors are capable of monitoring strain, temperature, pressure, and vibration. While the success of fiber optic monitoring has been clearly demonstrated, the sensors are now under consideration for automation applications. This paper details the plausibility of using pressure measurements from post-installed fiber Bragg grating (FBG) sensors with Model Predictive Control (MPC) to suppress severe slugging in subsea risers. Prior control schemes demonstrate that slugging is mitigated using …

The Performance Of Structured High-Capacity Si Anodes For Lithium-Ion Batteries, Jui Chin Fan

Theses and Dissertations

This study sought to improve the performance of Si-based anodes through the use of hierarchically structured electrodes to provide the nanoscale framework needed to accommodate large volume changes while controlling the interfacial area – which affects solid-electrolyte interphase (SEI) formation. To accomplish this, electrodes were fabricated from vertically aligned carbon nanotubes (VACNT) infiltrated with silicon. On the nanoscale, these electrodes allowed us to adjust the surface area, tube diameter, and silicon layer thickness. On the micro-scale, we have the ability to control the electrode thickness and the incorporation of micro-sized features. Treatment of the interfacial area between the electrolyte and …

Simulation Of Drainage Rates Of A Flexible Fiber Network On Wire Screen, Yihsin Tang

Masters Theses

A forming process of a fiber mat over a filter or wire net/screen, which can move horizontally, is numerically simulated. A lattice Boltzmann equation is used to simulate fluid velocity, vorticity and structures and a lattice spring model is employed to mimic the collective motion of up to 750 flexible fibers, with aspect ratio of 20.

The interaction between the fluid and fibers is handled by an immersed boundary method. The fiber motion is driven by the hydrodynamic forces and the gravity of both fluid and solid fibers and disturbed by the horizontal shear force between the fluid and the …

High-Throughput Screening Using Fourier-Transform Infrared Imaging, Erdem Sasmaz, Kathleen Mingle, Jochen A. Lauterbach

Faculty Publications

Efficient parallel screening of combinatorial lib­ra ries is one of the most challenging aspects of the high­throughput (HT) heterogeneous catalysis workflow. Today, a number of methods have been used in HT catalyst studies, including various optical, mass­spectrometry, and gas­chromatography techniques. Of these, rapid­scanning Fourier­transform infrared (FTIR) imaging is one of the fastest and most versatile screening techniques. Here, the new design of the 16­channel HT reactor is presented and test results for its accuracy and reproducibility are shown. The performance of the system was evaluated through the oxidation of CO over commercial Pd/Al2O3 and cobalt oxide nanoparticles synthesized with different …

A More Superior Preformed Particle Gel With Potential Application For Conformance Control In Mature Oilfields, Paul Tongwa, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The present work presents a nanocomposite preformed particle gel for conformance control in mature oilfields. This product was observed to have a better performance than conventional hydrogels without nanomaterials. Preformed particle hydrogel was designed by the reaction of monomer, initiator, crosslinker, additives, and calcium montmorillonite nanomaterial, whereas conventional hydrogel is designed from just monomer, initiator, crosslinker and additives. The presence of nanomaterial in hydrogel design affords it tremendous improvement in nanocomposite gel properties and behavior compared to conventional hydrogels without any nanomaterial. Additionally, swelling performance, post-degraded gel viscosity, and long-term thermal resistance of nanocomposite gel increased by several orders of …

Experimental Determination Of Solids Suspension With Angled Impeller In A Pharmaceutical Mixing Vessel, Yingxi Tang

Theses

Angled-mounted impellers are commonly used in a number of pharmaceutical industry applications, from laboratory reactors to full-scale tanks. In these systems, the impeller is not centrally and vertically mounted, as in most stirred vessels, but it enters the vessel, and is therefore immersed in the fluid, at an angle from the vertical. This arrangement provides some baffling effects that would not otherwise exist if the impeller was centrally mounted.

One common requirement for such systems is that they are capable of suspending small solids dispersed in the liquid. Therefore, it is critical to know the value of the minimum agitation …

The Kinetics Of Drug Dissolution In Polymers During Hot-Melt Extrusion, Huayang Fang

Theses

Extrusion has been a most important and widely used continuous process in polymer processing for over one hundred and fifty years. However, it has only been recently applied and adopted by the pharmaceutical industry to prepare solid oral dosage formulations with increased bioavailability for the poorly-water soluble drugs and controlled release characteristics for the water-soluble drugs. In pharmaceutical Hot-melt extrusion poorly water soluble drug particulates are mixed with water soluble polymer excipient particulates and fed in the extruder, where the polymer is melted, after which the drug particulates begin to dissolve into the polymer melt. Extrusion-generated mixing accelerates dissolution process. …

Experimental Determination Of The Agitation Requirements For Solids Suspension In Dissolution Systems Using A Mini Paddle Apparatus, Yang Song

Theses

Dissolution testing is a critical step in quality control of manufactured final products in the pharmaceutical industry. The United State Pharmacopeia (USP) Dissolution Testing Apparatus 2 (paddle) is the most widely used dissolution test devices in the pharmaceutical industry to formulate solid drug dosage forms and to develop quality control specifications for its manufacturing process.

Mini vessels and mini paddle dissolution testing systems are smaller versions of the USP 2 Apparatus. The concept of the mini paddle apparatus is similar to that of the USP 2 setup but it is scaled down about to 1/5 of the volume and 40% …

Effect Of Impeller Submergence On Power Dissipation And Solids Suspension In Mixing Systems Equipped With Pitch-Blade Turbines, Yufeng Song

Theses

Mixing and dispersion of solids in a liquid is a process frequently encountered in the pharmaceutical industry and often conducted in cylindrical baffled tanks stirred by mechanical impellers. In operations where the liquid level is decreased (as often which emptying the tank) the process must be stopped when the solids are no longer suspended. In this work, the minimum agitation to suspend solids (Njs) when the liquid level was lowered, and the impeller submergence S_b changed as a result were determined for the case of a six-blade, pitch-blade turbine (6-PBT) impeller. The power consumed by the impeller …

Principles And Applications Of Mechanical Dry Coating - Review And State-Of-The-Art, Sayani Bhaumik

Theses

Dry Coating of powders to form composite particulates has been firmly established and has garnered interest both in academia and industry due to its myriad applications. This thesis work is an attempt to map the progress of the dry coating technology from its incipient years in the '80s to the thriving practice in the present day. Dry coating is a relatively simple approach to coat powders with specific guest particles via mechanical means to produce composites with desired tailor-made properties, without the constraints of harmful emissions or huge capital investment. Composite particulates with enhanced flowability, high-temperature resistant properties, and modified …

Potable Water Production From Third River In Nasiriyah City, Ahmed Faiq Al-Alawy, Jaafar Jabbar Madlool, Ali Ibrahim Neamah

The Hilltop Review

The present work aims to study the efficiency of coagulation/ flocculation as pretreatment then using membrane technology, microfiltration (MF) and Reverse Osmosis (RO), for treatment of water of Third River in Nasiriyah city in Iraq. Effects of operating parameters such as coagulant dosage, speed and time of slow mixing step and settling time in the pretreatment stage were studied. Also feed turbidity and TSS in the MF stage were studied. Also feed concentration, temperature and operating time, in the RO stage were studied. The results showed that the optimum dosage for alum was 40, 45 and 50 ppm. While, for …

Photocatalytic Mineralization Of Phenol On Fluidized Titanium Oxide-Coated Silica Gel, Guillermo J. Rincon

LSU New Orleans Theses and Dissertations

A bench-scale tubular reactor with recirculation was built in order to study the efficiency of the photocatalytic oxidation of phenol on fluidized titanium oxide-coated silica gel beads. A UV-C lamp placed along the central vertical axes of the reactor was used as source of photons. A bed of silica gel beads was fluidized by means of fluid recirculation and forced to follow upward helical flow around the lamp. Anatase was successfully synthetized on silica gel particles of average diameters 224, 357 and 461 µm, as confirmed by scanning electron micrographs, through a sol-gel technique using a titanium (iv)isopropoxide / hydrochloric …

Three-Dimensional Ideal Gas Reference State Based Energy Function, Avdesh Mishra

LSU New Orleans Theses and Dissertations

Energy functions are found to be a key of protein structure prediction. In this work, we propose a novel 3-dimensional energy function based on hydrophobic-hydrophilic properties of amino acid where we consider at least three different possible interaction of amino acid in a 3-dimensional sphere categorized as hydrophilic versus hydrophilic, hydrophobic versus hydrophobic and hydrophobic versus hydrophilic. Each of these interactions are governed by a 3-dimensional parameter alpha used to model the interaction and 3-dimensional parameter beta used to model weight of contribution. We use Genetic Algorithm (GA) to optimize the value of alpha, beta and Z-score. We obtain three …

Effects Of Biomass Moisture Content On Volatile Flame Length During Cofiring With Coal, Matthew Pollard

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cofiring biomass with coal can contribute to meeting Renewable Portfolio Standards (RPS) and reduce pollutant emissions. The physical characteristics and composition of biomass can vary significantly, which can affect the combustion characteristics. When cofiring biomass with coal, these differences can impact the structure of the volatile flame, the region where combustion of volatiles dominates. The length and location of the volatile flame is important to flame stability and determines the location and extent of volatile release. This has an effect on pollutant emissions, such as NOx (nitrogen oxides). Previously, the effects of parameters such as cofiring ratio, particle size, and …

Measuring The Effectiveness Of Photoresponsive Nanocomposite Coatings On Aircraft Windshields To Mitigate Laser Intensity, Ryan S. Phillips, Hubert K. Bilan, Zachary X. Widel, Randal J. Demik, Samantha J. Brain, Matthew Moy, Charles Crowder, Stanley L. Harriman, James T. O'Malley Iii, Joseph E. Burlas, Steven F. Emmert, Jason J. Keleher

Journal of Aviation Technology and Engineering

In 2004, pilots reported 46 laser illumination events to the Federal Aviation Administration (FAA), with the number increasing to approximately 3,600 in 2011. Since that time, the number of reported laser incidents has ranged from 3,500 to 4,000. Previous studies indicate the potential for flight crewmember distraction from bright laser light being introduced to the cockpit. Compositional variations of the photoresponsive nanocomposite coatings were applied to an aircraft windscreen using a modified liquid dispersion/heating curing process. The attenuating effects of the deposited films on laser light intensity were evaluated using an optical power meter and the resultant laser intensity data …

Heat Integration Of An Aniline Production Process To Optimize Cost Savings And Reduce Energy Usage, Dillon Ashby

Senior Theses

The purpose of this project was to individually complete a heat integration optimization for my group’s senior design project, a process for the large-scale production of aniline.

Bio-Inspired Structural Colors Produced Via Self-Assembly Of Synthetic Melanin Nanoparticles, Ming Xiao, Yiwen Li, Michael C. Allen, Dimitri D. Deheyn, Xiujun Yue, Jiuzhou Zhao, Nathan C. Gianneschi, Matthew D. Shawkey, Ali Dhinojwala

Polymer Science Faculty Research

Structural colors arising from interactions of light with submicron scale periodic structures have been found in many species across all taxa, serving multiple biological functions including sexual signaling, camouflage, and aposematism. Directly inspired by the extensive use of self-assembled melanosomes to produce colors in avian feathers, we set out to synthesize and assemble polydopamine-based synthetic melanin nanoparticles in an effort to fabricate colored films. We have quantitatively demonstrated that synthetic melanin nanoparticles have a high refractive index and broad absorption spanning across the UV–visible range, similar to natural melanins. Utilizing a thin-film interference model, we demonstrated the coloration mechanism of …

Comparison Of Low-Temperature Co-Fired Ceramic And Direct Bonded Copper For Single Ended Primary Inductance Topology, Kristopher Cody Johnson

Electrical Engineering Undergraduate Honors Theses

This work examines the thermal dissipation characteristics of Low-Temperature Co-fired Ceramic (LTCC) and Direct Bonded Copper (DBC) with the implementation of a Single Ended Primary Inductance Converter (SEPIC) topology. The advantages and disadvantages of the two substrates will be explored in addition to a description of the design and control of the SEPIC. It will be shown that the DBC implementation is superior with regards to thermal dissipation, but that LTCC has advantages in high- density packaging, RF applications, and embedded components. These substrates and converters provide many advantages in industrial applications that include automotive and grid level implementations. Additional …

A Study On The Micro Electro-Discharge Machining Of Aerospace Materials, Mychal-Drew Moses

Masters Theses & Specialist Projects

Electrical Discharge Machining (EDM) is a non-traditional machining process that uses hundreds of thousands of minute electrical sparks per second to machine any electrically conductive material, no matter the hardness or how delicate it is. EDM allows a much greater range of design possibilities, unconstrained from the traditional machining processes, in which material is removed mechanically by either rotating the cutting tool or the work piece. Shapes that were impossible to machine by any other method, such as deep, precision, square holes and slots with sharp inside corners, are readily produced. It provides accurate geometries in high- aspect ratio holes …

Characterization Of Nano-Porous Si-Cu Composites To Enhance Lubricant Retention Impacting The Tribological Properties Of Sliding Surfaces, Julius Sheldon Morehead

Graduate Theses and Dissertations

As the expectations for modern machinery's tribological and thermal performances continue to rise, the retention of lubricant on the contact surfaces of their sliding components becomes an increasingly important issue. Friction and wear cause heat-related failures which lead to catastrophic damage to machinery. Evaporation of a lubricant's volatile constituents as well as lubricant migration leads not only to a reduction in lubricant quantity but also in its quality, thus facilitating component failures. In order to enhance component reliability, the surface should incorporate features that actively retain lubricants. The unique properties of nano-porous topographies such as their high surface area-to-volume ratio …

Effective Antisense Design Using An Ensemble Of Energetically Sub-Optimal Secondary Mrna Structures, Andrea M. Divenere

University Scholar Projects

There is a current deficit of effective therapies against bacterial infection. Many strategies seek using small molecules to target the infectious pathogen. One approach involves direct manipulation of the pathogen at the RNA level. Messenger RNA (mRNA) is a genetic transcript that encodes the fundamental instruction for protein production. Inhibiting mRNA translation effectively prevents protein synthesis.

The therapeutic agent must physically access mRNA to effectively block its message from being read. A technique has arisen where a complementary nucleic acid binding strand, called antisense, is generated to impede protein synthesis. An issue in creating effective antisense is finding mRNA target …

Titanium Dioxide Nanoparticles Trigger Loss Of Hepatic Function And Perturbation Of Mitochondrial Dynamics In Primary Hepatocytes, Vaishaali Natarajan

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Titanium dioxide (TiO₂) nanoparticles are one of the most highly manufactured nanomaterials in the world with applications in copious industrial and consumer products. The liver is a major accumulation site for many nanoparticles, including TiO₂, directly through intentional ingestion or indirectly through increased environmental contamination and unintentional ingestion via water, food or animals. Growing concerns over the current usage of TiO₂ coupled with the lack of mechanistic understanding of its potential health risk is the motivation for this study. Here we determined the toxic effect of three different TiO₂ nanoparticles (commercially available rutile, anatase …

Engineering Of Lipid Nanoparticles For Advanced Drug Deilvery Applications, Stephen L. Hayward

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

‘Nanomedicine’, the application of nanotechnology principles to the field of medicine, has stimulated the development of nano-platforms for next generation drug delivery. By exploiting nanoscale properties of materials to selectively alter intrinsic characteristics of therapeutics, researchers have improved the efficacy and pharmacokinetic profiles for a variety of drug types. Despite preliminary commercial and clinical success, there still remains a need to develop an improved delivery platform that can provide high cargo entrapment, efficient intracellular delivery, evasion of intracellular degradation pathways, and provide cell population specific targeting.

In this study we engineered a nanocarrier system composed of a core bilayer structure …

Nanoscale Electrode Architectures For Electrochemical Energy Conversion And Storage., Venkat Kalyan Vendra

Electronic Theses and Dissertations

Nanoscale electrode architectures are at the heart of photoelectrochemical devices converting sunlight into electricity and electrochemical devices that store energy. Advanced nanomaterials encompassing 1-D architectures such as single crystalline metal oxide nanowires, 2-D architectures such graphene nanosheets and nanoparticle-nanowire hybrids have garnered significant interest as promising materials for fabricating thicker electrodes due their unique electronic, phase transformation and strain relaxation properties. However, electrode architectures incorporating these advanced nanomaterials will have a transformational impact on large scale electrode manufacturing only if the challenges associated with the electrode durability are addressed. At a fundamental level, the reactions happening at the electrode-electrolyte interface …

Evaluating The Viability Of Graphene Oxide For The Removal Of Ni(Ii) Ions From Waste Water, Cale M. White

Biomedical Engineering Undergraduate Honors Theses

When levels of heavy metal ions such as nickel (Ni), copper (Cu), lead (Pb), Zinc (Zn), and Cobalt (Co) exceed the tolerance values for industrial wastewater, it can devastate the environment as well as the health of the individuals consuming the water. Heavy metal ions are not biodegradable and will accumulate in organic matter.(1) This accumulation leads to toxic levels in the blood and hence damage to nerve tissue, kidneys, the liver, and other vital organs. (2) Effective removal processes of these heavy metals from water must be developed. This study explores a method to adsorb nickel from water with …

Electrocatalyst Decorated Hematite Nanowire Arrays For Photoelectrochemical Water Splitting., Erica James

College of Arts & Sciences Senior Theses

Solar power is a leading option for renewable energy. However, storing solar energy is one of the leading pitfalls in this field, and one viable option is to store solar energy in chemical bonds, for example in H2 via water splitting. Hematite, α-Fe2O3, is one of the possible semiconductors that has been researched to drive photoelectrolysis of water. Hematite alone is not a decent material for photoelectrolysis because of the large activation energy required to begin the reaction. To make hematite more useful for photoelectrolysis an electrocatalyst, such as nickel oxide, is needed. In this experiment, nickel (II) nitrate was …