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Full-Text Articles in Engineering

Selective Nanoparticles For Antimicrobial Therapies And Mri Diagnostics, Mark Andrew Hoppens Jun 2013

Selective Nanoparticles For Antimicrobial Therapies And Mri Diagnostics, Mark Andrew Hoppens

LSU Master's Theses

Early diagnosis and treatment of an infection and the selectivity of the treatment method are three parameters, which if optimized will greatly enhance a patient’s prognosis. Thus these three components have been, and continue to be extensively studied. Advances in biosynthesis and nanofabriciation have provided researchers with new tools with which to improve diagnostic and therapeutic techniques. Of these, inorganic nanoparticles (NPs) have shown great promise. Metallic nanoparticles have been demonstrated to successfully serve as antimicrobials, platforms for the transportation of therapeutic molecules, CT and MRI contrast agents, and thermal ablation. The recent paradigm of theranostics proposes substances that serve …


The Uplift Resistance Of Spartina Alterniflora In A Louisiana Salt Marsh, James Madison Bouanchaud Iii Jan 2013

The Uplift Resistance Of Spartina Alterniflora In A Louisiana Salt Marsh, James Madison Bouanchaud Iii

LSU Master's Theses

The uprooting resistance of Spartina Alterniflora was measured in Terrebonne Bay and Bay Jimmy, both of which are located in Louisiana. The parameters collected included plant uprooting resistance, stem diameter, and stem height. Seasonal variations and site specific properties were considered. A device was designed and constructed that was able to perform the specific testing under the constraints of the field site. The device consisted of a winch mounted to a tripod and connected to an inline load cell to measure the uprooting resistance. The data sets were analyzed to determine the relationship between the uprooting resistance and the physical …


Electric Field Influence On The Combustion Of Fuel Droplets, Solomon Benghan Jan 2013

Electric Field Influence On The Combustion Of Fuel Droplets, Solomon Benghan

LSU Master's Theses

Improving the combustion efficiency of fuels in combustion devices has become imperative in the face of the diminishing rate of the discovery of new energy sources and an ever increasing demand for energy. While there are other ways of improving combustion efficiency, this study investigated the effect of electric field on the combustion of fuel droplets. In order to model the physics of the problem, a mass transfer evaporation model, heat transfer evaporation model and a simple burning droplet model were considered and their result compared to existing result from literature. A burning rate constant of 1.380mm2/s, 14.910mm2/s and 0.612mm2/s …


Liposomal Uptake Of Silver And Gold Nanoparticles, Dipon Chanda Jan 2013

Liposomal Uptake Of Silver And Gold Nanoparticles, Dipon Chanda

LSU Master's Theses

The main objective of this work is to study the liposomal uptake of silver and old nanoparticles. Liposomes were prepared in Heating Method. The phospholipids used to prepare liposomes are 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (16:0 PC); 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (16:0 PG); 1,2-distearoyl-sn-glycero-3-phosphocholine (18:0 PC); 1,2-distearoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt) (18:0 PG).Four different combinations of phospholipids were used to prepare liposomes. In all four combinations two types of phospholipids were used. The liposomes were incubated for 30 minute, 1 hour, 2 hour and 4 hour with silver and gold nanoparticles in streptavidin coated glass slide. All four liposomal formulations had a biotinylated lipid (1-oleoyl-2-[12-biotinyl(aminododecanoyl)]-sn-glycero-3-phosphocholine) which has a string …


Modeling, Simulation And Analysis Of Renewable Energy Production Systems: Application To Multi-Product Biorefineries, Aryan Geraili Nejadfomeshi Jan 2013

Modeling, Simulation And Analysis Of Renewable Energy Production Systems: Application To Multi-Product Biorefineries, Aryan Geraili Nejadfomeshi

LSU Master's Theses

The primary purpose of this research is to investigate the design and modelling of fully integrated processes which utilize renewable feedstock as raw materials and evaluate the alternative technology and possible process integration options for biorefinery processes to select the optimal configuration based on the production yields and economical profit criteria. The case study considered in this work is a lignocellulosic biorefinery plant which has different technology choices for each section of the process and the ability to produce multi-products from lignocellulosic raw materials. We analyzed different scenarios by simulating the superstructures in Aspen Plus. To incorporate more non-linarites in …


Modeling Of Shear Strengthening Of Reinforced Concrete Beams Retrofitted With Externally Bonded Fiber Reinforced Polymers, Srinivasa Anusha Bellamkonda Jan 2013

Modeling Of Shear Strengthening Of Reinforced Concrete Beams Retrofitted With Externally Bonded Fiber Reinforced Polymers, Srinivasa Anusha Bellamkonda

LSU Master's Theses

This thesis presents a study on the shear retrofit of reinforced concrete (RC) beams with externally bonded fiber reinforced polymers (FRP), since it is very important for RC beam to have a shear strength that is higher than the flexural strength in order to ensure ductile flexural failure mode. The study proposes a new model to predict the FRP shear strength contribution for different modes of failure, i.e., bending, shear with FRP rupture, shear with FRP debonding, and mixed shear-flexure and various retrofit techniques, i.e., side-bonding, U-jacketing, and full wrapping. The proposed model is compared to other existing models for …


Catalytic Conversion Of Biomass Derived Syngas To Liquid Fuels Using Fischer-Tropsch Synthesis, Pratibha Sharma Jan 2013

Catalytic Conversion Of Biomass Derived Syngas To Liquid Fuels Using Fischer-Tropsch Synthesis, Pratibha Sharma

LSU Master's Theses

Biomass gasification and subsequent conversion to liquid hydrocarbons using Fischer-Tropsch synthesis is a promising source of energy in today’s scenario when the focus has shifted from conventional fuels to alternate sources of energy. Biomass derived syngas is different from other sources of syngas such as steam reforming of methane followed by water gas shift, in terms of H2/CO ratio. Biomass syngas is usually hydrogen deficient and contains various impurities which need to be removed prior to Fischer-Tropsch Synthesis. Syngas derived from biomass also differs significantly with the different sources of biomass, gasification process and the cleanup conditions it is subjected …


Effect Of Surface Roughness On The Efficiency Of Self-Healing Polymers, Ifeanyi Janarus Okoro Jan 2013

Effect Of Surface Roughness On The Efficiency Of Self-Healing Polymers, Ifeanyi Janarus Okoro

LSU Master's Theses

A shape memory polymer (SMP) is a smart material capable of maintaining two distinct shapes depending on its temperature. A SMP is soft at temperatures above its glass transition temperature but hard below it. When copolyester thermoplastic additives are dispersed in a SMP, it becomes a SMP-based particulate composite capable of self-healing at both the molecular level and the structural level. This makes it very desirable for industrial applications. Upon damage to the composite, the surfaces at the damage interface have to come into contact for efficient healing; the shape memory effect, coupled with a confined recovery (healing) process, ensures …


Deflection Based Condition Assessment For Rolling Wheel Deflectometer At Network Level, Karthik Venkatesh Dasari Jan 2013

Deflection Based Condition Assessment For Rolling Wheel Deflectometer At Network Level, Karthik Venkatesh Dasari

LSU Master's Theses

The Rolling Wheel Deflectometer (RWD) is capable of measuring pavement deflection at high speeds without traffic interruption or compromising safety along tested road segments. To optimize the use of RWD at the network level, an assessment tool is needed to incorporate RWD data into current Pavement Management System (PMS) and to identify pavements in need of maintenance or rehabilitation. The objective of this study is to present the development of a screening tool, referred to as the pavement assessment triangular model, to predict pavement overall conditions based on RWD deflection, roughness measurements, and surface conditions as described by the Pavement …


Comparison Of In Vivo Human Knee Joint Kinematics Using Axodes, Jacob Hipps Jan 2013

Comparison Of In Vivo Human Knee Joint Kinematics Using Axodes, Jacob Hipps

LSU Master's Theses

The human knee is of particular interest because of its importance in mobility. Pain and stability can be directly related to the motion, or kinematics, of the knee. Many studies have been conducted to quantify human knee kinematics, both in vitro and in vivo. One of the inherent issues with in vivo, skin mounted measurement systems is that they do not account for soft tissue artifact. Compensation for soft tissue artifact has been a difficult challenge for skin mounted tracking systems and has not yet been achieved. Therefore, bone mounted skeletal pins were chosen as the method of gathering kinematic …


Performance And Power Comparisons Between Fermi And Cypress Gpus, Ying Zhang Jan 2013

Performance And Power Comparisons Between Fermi And Cypress Gpus, Ying Zhang

LSU Master's Theses

In recent years, modern graphics processing units have been widely adopted in high performance computing areas to solve large scale computation problems. The leading GPU manufacturers Nvidia and AMD have introduced series of products to the market. While sharing many similar design concepts, GPUs from these two manufacturers differ in several aspects on processor cores and the memory subsystem. In this work, we conduct a comprehensive study to characterize and compare the architectural features of Nvidia’s Fermi and AMD’s Cypress GPUs. We first investigate the performance and power consumptions of an AMD Cypress GPU. By employing a rigorous statistical model …


Reaction Of Green Leaf Volatiles As A Source Of Secondary Organic Aerosols In Fog Droplets, Amie Kathryn Hansel Jan 2013

Reaction Of Green Leaf Volatiles As A Source Of Secondary Organic Aerosols In Fog Droplets, Amie Kathryn Hansel

LSU Master's Theses

Green leaf volatiles (GLVs) are a group of biogenic volatile organic compounds (BVOCs) released into the atmosphere by vegetation when plants undergo stress or mechanical damage. BVOCs produce secondary organic aerosol (SOA) in the gas phase; however, their oxidation as a source of SOA in the liquid phase has not been investigated. Once released into the atmosphere, water-soluble GLVs partition into atmospheric water phases such as fog, mist, dew or rain, where they are oxidized by hydroxyl radicals (ÿOH). Photochemical oxidation yields products that are higher in molecular weight, more polar, more oxygenated, and lower in vapor pressure. When the …


Discrete Time Modeling And Control Of Dc/Dc Switching Converter For Solar Energy Systems, Shaghayegh Kazemlou Jan 2013

Discrete Time Modeling And Control Of Dc/Dc Switching Converter For Solar Energy Systems, Shaghayegh Kazemlou

LSU Master's Theses

Distributed generation networks including micro grids benefit from solar cells that are controlled by dc-dc converters. In this research a nonlinear discrete-time model for a buck converter tied to a solar system is derived with unknown internal dynamics. Then, adaptive neural network (NN) controller is employed to enhance stability of dc-dc converter connected to grid-tie inverter (GTI) in the presence of power system disturbances. The NN weights are tuned online by using a novel update law. By using Lyapunov techniques, all signals can be shown to be uniformly ultimately bounded (UUB). In addition, the interaction of the converter with the …


Closed Form Solutions To The Optimality Equation Of Minimal Norm Actuation, Jorge Antonio Guerra Jan 2013

Closed Form Solutions To The Optimality Equation Of Minimal Norm Actuation, Jorge Antonio Guerra

LSU Master's Theses

This research focused on the problem of minimal norm actuation in the context of partial natural frequency or pole assignment applied to undamped vibrating systems by state feedback control. The result of the research was the closed form solutions for the minimal norm control input and gain vectors. These closed form solutions should took open loop eigenpairs and the desired frequencies of the controlled system and outputted the optimal controller parameters. This optimization technique ensures that the system’s dynamics will be effectively controlled while keeping the controller effort minimal. The controller must then be able to shift only the desired …


Effects Of Partial Confinement And Local Heating On Healing Efficiencies Of Self-Healing Particulate Composites, Jonah Champagne Jan 2013

Effects Of Partial Confinement And Local Heating On Healing Efficiencies Of Self-Healing Particulate Composites, Jonah Champagne

LSU Master's Theses

Shape memory polymers are smart materials that can be trained to hold a temporary shape through programming and regain their original shape upon heating. Since there discovery in the 1960s, much research has been devoted to the study of these polymers. Of particular interest in recent years is the study of self-healing shape memory polymers. In a previous study, it has been shown that in order for efficient healing to take place in self-healing shape memory polymers, confinement during healing is essential. Moreover, a two-step close-then-heal (CTH) approach to healing was suggested. It was shown that use of this CTH …


Aggregation Of Uncontrolled Fluids During Catastrophic System Failures In Offshore Environments, James Thomas Stiernberg Jan 2013

Aggregation Of Uncontrolled Fluids During Catastrophic System Failures In Offshore Environments, James Thomas Stiernberg

LSU Master's Theses

Safety culture relating to offshore operations has shifted since the Deepwater Horizon blowout and resulting oil spill. This incident has prompted the research of high volume spills during all stages of hydrocarbon exploration and production. This study particularly covers the interactions of wells and offshore networks as they pertain to situations where a release of reservoir fluids to the environment is occurring. Primary concerns of this investigation are stream confluences, leak modeling, and fluid behavior; the first two will be handled with various numerical software packages (OLGA®, CFD, and nodal analyses) while the later will require more rigorous treatment and …


Engineering Of Hydroponic Systems To Enhance Biomass Of Sea Oats (Uniola Paniculata), Stefanie Renee Gilliam Jan 2013

Engineering Of Hydroponic Systems To Enhance Biomass Of Sea Oats (Uniola Paniculata), Stefanie Renee Gilliam

LSU Master's Theses

Restoration projects use native plants such as sea oats (Uniola paniculata) to help stabilize the coast. Sea oats are a native grass that can collect blowing sand to build dunes. Sea oats used in the restoration projects can be produced using sexual or asexual techniques. An ideal seedling would be genetically distinct, have increased seed production and germination, and have superior vegetative biomass. Finding ways to produce, propagate, and grow coastal plants such as sea oats effectively is critical to efforts to reduce erosion. In this study, production of sea oats via greenhouse based hydroponic systems was studied. This was …


Documenting Postural Changes And Repetition Among Violin Players And Their Influence In The Development Of Musculoskeletal Disorders, Cristina Handal Jan 2013

Documenting Postural Changes And Repetition Among Violin Players And Their Influence In The Development Of Musculoskeletal Disorders, Cristina Handal

LSU Master's Theses

The objective of this study was to document the changes in posture and the number of wrist and forearm repetitions among violin/viola players during an experiment session to attempt to understand the development of musculoskeletal disorders. Also, the perception of discomfort and pain felt by the violin/viola players in the past and the number that had been diagnosed with a disorder was documented. Finally, possible correlations were calculated between pain/discomfort with variables like the number of years playing the violin, hours of practice/day, frequency of pain, gender, and dominant hand and among different pain/discomfort variables (pain/discomfort before the experiment, after …


Parametric Optimization Of A Single-Tracked Vehicle, Darrick Jason Berner Jan 2013

Parametric Optimization Of A Single-Tracked Vehicle, Darrick Jason Berner

LSU Master's Theses

ABSTRACT The purpose of a suspension system for a vehicle is to contribute to the handling and assist in isolating the occupants from vibrations due to road irregularities. Generally, these primary functions are often at odds so the goal is to design a suspension system that finds the appropriate compromise. The focus of this thesis is to develop a two degree of freedom model and use parametric analysis to demonstrate an optimization technique by varying several geometric characteristics on a single-track vehicle. Furthermore, a dynamic vibration absorber will be added to the model to demonstrate its effect on the system. …


Numerical Evaluation And Analysis Of The Adhesion Phenomena In Thermal Barrier Coating Systems Through Bio-Mimicking Plasma Process, Naser Imran Hossain Jan 2013

Numerical Evaluation And Analysis Of The Adhesion Phenomena In Thermal Barrier Coating Systems Through Bio-Mimicking Plasma Process, Naser Imran Hossain

LSU Master's Theses

Thermal Barrier Coatings or TBCs when abbreviated are an imperative part of the thermal protection system of expensive equipment and machinery in the automobile and aeronautics industry. They provide protection to expensive alloy materials upto a temperature of 2700° C without expensive metallurgical additions. Unfortunately, the problem of coating adhesion has plagued the TBC field for years, leading to catastrophic failures in critical TBC systems. Efforts to chemically improve bond strength has not been entirely successful, so the only other efficient way to do this would be some kind of mechanical interlocking that occurs at micro/nano scales. This research work …


Design Flood Elevations Beyond Code Requirements And Current Best Practices, Frank H. Bohn Jan 2013

Design Flood Elevations Beyond Code Requirements And Current Best Practices, Frank H. Bohn

LSU Master's Theses

In the United States, nearly 9 million people, 3.0% of the population, live in areas subject to the 1% annual chance (100-yr) coastal flood hazard. New construction and substantial improvements in coastal high hazard areas require structures to be elevated above the design flood elevation (DFE), without the use of fill (Bellomo et al. 1999). Building code requirements for flood elevation are linked to the National Flood Insurance Program (NFIP) insurance policies, and represent the minimum requirement for building elevation. Current elevation procedures are limited to the 100-year base flood elevation with minimal guidance beyond the 100-year elevation in many …


Variability And Characteristics Of Recycled Asphalt Shingles Sampled From Different Sources, Aaron Lodge Jan 2013

Variability And Characteristics Of Recycled Asphalt Shingles Sampled From Different Sources, Aaron Lodge

LSU Master's Theses

Recent literature studies have demonstrated depletion in natural resources; therefore, making resources needed for the pavement industry is more costly. There is a need to minimize cost and to try to reduce the depletion of natural resources. While the recycling of asphalt shingles is beneficial in reducing the consumption of virgin materials, pavement performance should not be compromised. One major concern with recycled asphalt shingles (RAS) relates to the variability in the properties of the recycled materials originating from different sources. In addition, the rheological properties of RAS have not been evaluated as well as its influence on the virgin …


Erosional Resistance Of Cohesive Sediments In Coastal Saltmarshes, Hem Raj Pant Jan 2013

Erosional Resistance Of Cohesive Sediments In Coastal Saltmarshes, Hem Raj Pant

LSU Master's Theses

Louisiana’s saltmarshes, one of the most productive wetlands in the nation, are undergoing severe erosion due to hydrodynamic forces (storm surge) and sea level rise. The erosional behavior of coastal saltmarshes, which possess cohesive sediments as their integral components, are very difficult to analyze and understand. The erosional resistance of cohesive sediments determines the stability and sustainability of coastal wetlands. This erosional resistance is expressed as an erosion threshold or critical shear stress, which depends on various soil properties (e.g. water content, root content, organic matter content, and pore water salinity) affecting saltmarsh erodibility integratively. A cohesive strength meter was …


Novel Separation Strategy For Processing Biopyrolysis Liquids, Chuanlin Zhao Jan 2013

Novel Separation Strategy For Processing Biopyrolysis Liquids, Chuanlin Zhao

LSU Master's Theses

The separation of pyrolysis bio-oil is important for its role in upgrading oil quality and acquiring commercial byproducts. A selective separation method for biopyrolysis liquids is developed in this work. Two parts in succession are involved as the first one aims at selectively removing some of the heaviest fractions from bio-oil. Chromatographic adsorption results show that Class C Fly ash and pyrolysis Bio-char have potential for this goal at <300 ºC, byproduct like combined adsorbates / adsorbents could also be used directly in asphalt cement processes. Thereafter, the second part focuses on adsorbing light fractions like lighter acids and aldehydes selectively. Basic (modified) activated carbons display relatively low selectivity at ~250ºC, but they have better selectivity compared to unmodified activated carbons. Thus some carbon-coated mesoporous silica and alumina materials are also prepared for the adsorption of these light compounds in the future. The combination of the two parts of adsorptions would leave behind a middle distillate fraction which is the bio-oil fraction most amenable to catalytic upgrading, to either a fuel or chemical feedstock.


Thermal, Compositional, And Salinity Effects On Wettability And Oil Recovery In A Dolomite Reservoir, Azadeh Kafili Kasmaei Jan 2013

Thermal, Compositional, And Salinity Effects On Wettability And Oil Recovery In A Dolomite Reservoir, Azadeh Kafili Kasmaei

LSU Master's Theses

Low salinity and composition effects in improving oil recovery in sandstone reservoirs are known. However, these effects have not been thoroughly studied for the carbonate reservoirs. Because of the lack of the clay minerals in the carbonate rocks, the mechanisms for the improved oil recovery with low salinity, brine composition, and temperature may not be the same as those for sandstones. This experimental study attempts to investigate the effects of low salinity, brine composition, and temperature on wettability and oil recovery in a dolomite reservoir. Also, it is attempted to confirm that wettability alteration is the main mechanism for improvement …


Effect Of Rest Time On Heart Rate, Perceived Exertion, And Strength, Amir Bahador Bahmani Bahman Beiglou Jan 2013

Effect Of Rest Time On Heart Rate, Perceived Exertion, And Strength, Amir Bahador Bahmani Bahman Beiglou

LSU Master's Theses

Finding a proper work/rest schedule is considered an important factor for improved efficiency, safety, and a higher rate of productivity in the workplace. The purpose of this study was to determine the optimum rest period for lifting tasks using heart rate, perceived exertion, and physical strength. First, the maximum acceptable weight of the box to be lifted was determined for each one of 10 participants using a psychophysical approach. Then on separate days, participants were required to repetitively lift the box from knuckle height to shoulder height for 20 minutes. They were then allowed to rest 5, 10, 15, or …


Biofilter Treatment Of Gas Phase Β-Caryophyllene At Elevated Temperature, Yiying Yue Jan 2013

Biofilter Treatment Of Gas Phase Β-Caryophyllene At Elevated Temperature, Yiying Yue

LSU Master's Theses

Industrial wood processing operations generate a variety of gaseous emissions containing volatile organic compounds (VOCs). One of the VOCs emitted from the processing of coniferous softwood tree species is β-caryophyllene, a naturally occurring sesquiterpene of environmental concern. One approach that may be attractive for treating gaseous emissions of β-caryophyllene from wood processing operations is the use of fixed-film processes commonly referred to as biofiltration. Previously, it was established that β-caryophyllene can be successfully treated via biofiltration at temperatures in the mesophilic range. Many gaseous emissions from industrial wood processing operations, however, are higher in temperature than those employed in the …


Sedimentation Of Swarms Of Particles At Low And Moderate Reynolds Numbers, Oladapo Olanrewaju Ayeni Jan 2013

Sedimentation Of Swarms Of Particles At Low And Moderate Reynolds Numbers, Oladapo Olanrewaju Ayeni

LSU Master's Theses

The sedimentation of a cloud of particles in a viscous fluid at low and moderate Reynolds numbers has been studied using an Eulerian-Lagrangian multiphase flow approach. We looked at the volume fraction dependence of the settling cloud and find a similar dependence in the simulations as in the theoretical predictions of (Nitsche and Batchelor 1997). The average cloud settling velocity and the velocity fluctuations around this average are found to have a functional dependence on ö^1/3 at negligible Reynolds number. The velocity fluctuations display strong anisotropy with the magnitude of the vertical component almost three times the magnitude of the …


Synthesis Of Poly(L-Lactic Acid) Scaffolds From Dioxane/Ethanol Using Control Rate Freezing And Study Of Its Microstructural Properties, George Idicula Jan 2013

Synthesis Of Poly(L-Lactic Acid) Scaffolds From Dioxane/Ethanol Using Control Rate Freezing And Study Of Its Microstructural Properties, George Idicula

LSU Master's Theses

Bio-degradable poly (l-lactic acid) (PLLA) scaffolds were prepared by using thermally induced phase separation (TIPS) method. A solution of PLLA-Dioxane was formed by dissolving PLLA in dehydrated 1,4-Dioxane at three wt/vol percentages, specifically 3, 7 and 10%. This PLLA-Dioxane solution was then frozen in borosilicate glass vials (5mL) at three cooling rates (1, 10 and 40 ˚C/min) in a commercially available controlled rate freezer (CRF). The frozen solution was freeze-dried to sublimate the Dioxane. The microstructural properties of the resulting PLLA scaffolds were determined utilizing Scanning Electron Microscopy (SEM) images and uni- axial compressive testing. The relationship between the wt/vol …


Investigation Of Best Practices For Maintenance Of Concrete Bridge Railings, Angel Luis Lence Jan 2013

Investigation Of Best Practices For Maintenance Of Concrete Bridge Railings, Angel Luis Lence

LSU Master's Theses

Biodeterioration on concrete surfaces of vertical elements of bridges represents a serious challenge to the highway infrastructure in Louisiana. This investigation aims to document the causes of biodeterioration of concrete surfaces and to document current conventional and state-of-the-art practices implemented to prevent and clean biofilm. A comprehensive literature review of previous research has been carried out in order to determine the cause and mechanisms of the biodeterioration as well as to identify current methods that state DOTs have implemented in order to maintain their bridges and allow them to function in optimal structural and performance conditions. A survey was developed …