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The Investigation Of Valve Operators' Torque Production Capabilities And Optimal Handwheel Height, Angle, And Opening Technique, Saif K. Al-Qaisi Jan 2013

The Investigation Of Valve Operators' Torque Production Capabilities And Optimal Handwheel Height, Angle, And Opening Technique, Saif K. Al-Qaisi

LSU Doctoral Dissertations

This research consists of two projects concerned with handwheel-valve operations. The objectives of poject-1 were to: (1) introduce an ergonomically-modified valve-wrench and compare it to conventional valve-opening methods, in terms of efficiency (time to open valve), perceived physical exertion (Borg-scale), and muscle loading of shoulder and trunk muscles; and (2) determine whether the torque setting (15 Nm and 30 Nm) of the valve affects the preferred valve-opening method. Four methods were evaluated, including using bare hands (BH), conventional wrench-restricted (CW-R, assumes presence of obstructions), conventional wrench-unrestricted (CW-U, assumes no obstructions), and modified wrench (MW). Electromyography (EMG) activities were measured from …


Modeling Temporal And Spatial Variations In Dissolved Oxygen In Amite River, Vahid Zahraeifard Jan 2013

Modeling Temporal And Spatial Variations In Dissolved Oxygen In Amite River, Vahid Zahraeifard

LSU Doctoral Dissertations

A watershed-based modeling framework is developed in this dissertation for simulating temporal and spatial variations in DO in lowland rivers with organic-rich fine-grained sediment. The modeling framework is based on three major contributions/new models, including (1)VART-DO model for improved estimation of reaeration coefficient (K2) in natural streams, (2)VART-DOS model for simulation of temporal variations in DO in response to sediment resuspension, and (3)VART DO-3L model for simulation of spatial variations in DO. A major advantage of VART-DO model is the capability of simulating DO exchange across the water-sediment interface through the hyporheic exchange mechanism in addition to the air-water exchange. …


Steady And Unsteady Thermo-Strucural Simulation Of Thermally Actuated Micro- And Nano-Structures, Elham Maghsoudi Jan 2013

Steady And Unsteady Thermo-Strucural Simulation Of Thermally Actuated Micro- And Nano-Structures, Elham Maghsoudi

LSU Doctoral Dissertations

This dissertation provides a thermo-structural simulation for nano-scale and micro-scale structures with pinned and fixed boundary conditions which are either thermally positioned, buckled, or actuated. The study begins with simulating a pinned-pinned beam in micro-scale and nano-scale. The steady state thermo-structural equation is solved numerically using an implicit Finite Difference method implemented in Matlab to obtain the thermal positioning response, which is the thermally steady state center displacement, by adding a constant, time-independent heat flux to the structure. The results show the steady state thermal displacement of the system is a function of the geometry, pressure, material properties, and constant …


Molecular Dynamics Of Interfacial Phenomena At Air/Ice, Air/Water, And Air/Salt Water Interfaces, Thilanga Prabhash Liyana Arachchi Jan 2013

Molecular Dynamics Of Interfacial Phenomena At Air/Ice, Air/Water, And Air/Salt Water Interfaces, Thilanga Prabhash Liyana Arachchi

LSU Doctoral Dissertations

The purpose of this research is to investigate the adsorption of organic contaminants, namely polycyclic aromatic hydrocarbons (PAHs) and green leaf volatiles (GLVs), as well as their interactions with reactive oxygen species (ROSs) on atmospheric air/water and air/ice interfaces. In another series of projects, we studied several intermediate and semi-volatile organic compounds from oil (IVOCs and SVOCs, e.g., alkanes with 17-31 carbon atoms), surfactants and dispersants at air/salt water interfaces. These simulations are relevant to understand the fate of these compounds during the recent 2010 Deepwater Horizon (DWH) oil spill. The adsorption of gas-phase aromatics (benzene, naphthalene and phenanthrene), ROSs …


Framework Of Damage Detection In Vehicle-Bridge Coupled System And Application To Bridge Scour Monitoring, Xuan Kong Jan 2013

Framework Of Damage Detection In Vehicle-Bridge Coupled System And Application To Bridge Scour Monitoring, Xuan Kong

LSU Doctoral Dissertations

Most vibration-based damage identification methods make use of measurements directly from bridge structures with attached sensors. However, the vehicle moving on the bridge can serve as both an active actuator and a response receiver. This dissertation aimed to develop new methodologies to eventually detect bridge damages such as scour using the dynamic response of the vehicle. To reach the final objective, a framework of damage identification was developed first, which gave a guideline on the three crucial steps for damage detection. An optimization method was proposed that combines the Genetic Algorithm (GA) and the First Order (FO) method. It has …


Optimal Consignment Stocking Policies For A Supply Chain Under Different System Constraints, Hui Zhi Yi Jan 2013

Optimal Consignment Stocking Policies For A Supply Chain Under Different System Constraints, Hui Zhi Yi

LSU Doctoral Dissertations

The research aims are to enable the decision maker of an integrated vendor-buyer system under Consignment Stock (CS) policy to make the optimal/sub-optimal production/replenishment decisions when some general and realistic critical factors are considered. In the system, the vendor produces one product at a finite rate and ships the outputs by a number of equal-sized lots within a production cycle. Under a long-term CS agreement, the vendor maintains a certain inventory level at the buyer’s warehouse, and the buyer compensates the vendor only for the consumed products. The holding cost consists of a storage component and a financial component. Moreover, …


Quantification Of The Environmental Impact Of Titanium Dioxide Photocatalytic Pavements For Air Pollution Remediation, Heather Lee Dylla Jan 2013

Quantification Of The Environmental Impact Of Titanium Dioxide Photocatalytic Pavements For Air Pollution Remediation, Heather Lee Dylla

LSU Doctoral Dissertations

Photocatalytic concrete pavements are a promising technology for mobile source air pollution remediation, however before widespread application of this technology is realized many unanswered questions remain regarding its overall environmental impact. In response to these questions, the goal of this study was to increase the understanding of the environmental impact of photocatalytic concrete pavement highways. To achieve this goal, the objectives of this study were to (A) construct a model that evaluates the nitrogen oxides (NOx) reduction from photocatalytic pavements, (B) quantify the nitrates released from the photocatalytic degradation of NOx, and (C) identify and characterize pathways for TiO2 nanoparticle …


Automated Semantic Content Extraction From Images, Mahdi Arab Khazaeli Jan 2013

Automated Semantic Content Extraction From Images, Mahdi Arab Khazaeli

LSU Doctoral Dissertations

In this study, an automatic semantic segmentation and object recognition methodology is implemented which bridges the semantic gap between low level features of image content and high level conceptual meaning. Semantically understanding an image is essential in modeling autonomous robots, targeting customers in marketing or reverse engineering of building information modeling in the construction industry. To achieve an understanding of a room from a single image we proposed a new object recognition framework which has four major components: segmentation, scene detection, conceptual cueing and object recognition. The new segmentation methodology developed in this research extends Felzenswalb's cost function to include …


Digital Image-Based Frameworks For Monitoring And Controlling Of Particulate Systems, Bing Zhang Jan 2013

Digital Image-Based Frameworks For Monitoring And Controlling Of Particulate Systems, Bing Zhang

LSU Doctoral Dissertations

Particulate processes have been widely involved in various industries and most products in the chemical industry today are manufactured as particulates. Previous research and practise illustrate that the final product quality can be influenced by particle properties such as size and shape which are related to operating conditions. Online characterization of these particles is an important step for maintaining desired product quality in particulate processes. Image-based characterization method for the purpose of monitoring and control particulate processes is very promising and attractive. The development of a digital image-based framework, in the context of this research, can be envisioned in two …


Modeling And Simulation Of Surface Profile Forming Process Of Microlenses And Their Application In Optical Interconnection Devices, Zhengyu Miao Jan 2013

Modeling And Simulation Of Surface Profile Forming Process Of Microlenses And Their Application In Optical Interconnection Devices, Zhengyu Miao

LSU Doctoral Dissertations

Free space micro-optical systems require to integrate microlens array, micromirrors, optical waveguides, beam splitter, etc. on a single substrate. Out-of-plane microlens array fabricated by direct lithography provides pre-alignment during mask fabrication stage and has the advantage of mass manufacturing at low cost. However, this technology requires precise control of the surface profile of microlenses, which is a major technical challenge. The quality control of the surface profile of microlenses limits their applications. In this dissertation, the surface forming process of the out-of-plane microlenses in UV-lithography fabrication was modeled and simulated using a simplified cellular automata model. The microlens array was …


Psychological Behavior Analysis Using Advanced Signal Processing Techniques For Fmri Data, Charisma Dionne Edwards Jan 2013

Psychological Behavior Analysis Using Advanced Signal Processing Techniques For Fmri Data, Charisma Dionne Edwards

LSU Doctoral Dissertations

Psychological analysis related to voluntary reciprocal trust games were obtained using functional magnetic resonance imaging (fMRI) hyperscanning for 44 pairs of strangers throughout 36 trust games (TG) and 16 control games (CG). Hidden Markov models (HMMs) are proposed to train and classify the fMRI data acquired from these brain regions and extract the essential features of the initial decision of the first player to trust or not trust the second player. These results are evaluated using the different versions of the multifold cross-validation technique and compared to other speech data and other advanced signal processing techniques including linear classification, support …


Developing Defect-Tolerant Demolding Process In Nanoimprint Lithography, Alborz Amirsadeghi Jan 2013

Developing Defect-Tolerant Demolding Process In Nanoimprint Lithography, Alborz Amirsadeghi

LSU Doctoral Dissertations

Demolding, the process to separate stamp from molded resist, is most critical to the success of ultraviolet nanoimprint lithography (UV-NIL). In the present study we first investigated adhesion and demolding force in UV-NIL for different compositions of a model UV-curable resist containing a base (either tripropyleneglycol diacrylate with shorter chain length or polypropyleneglycol diacrylate with longer chain length), a cross-linking agent (trimethylolpropane triacrylate) and a photoinitiator (Irgacure 651). The demolding force was measured using a tensile test machine after imprinting the UV resist on a silicon stamp. In general, the shorter monomer shows a larger demolding force. Decreasing the cross-linking …


A Large Scale Network Model To Obtain Interwell Formation Characteristics, Seyedmohammadamin Gherabati Jan 2013

A Large Scale Network Model To Obtain Interwell Formation Characteristics, Seyedmohammadamin Gherabati

LSU Doctoral Dissertations

Limited data availability and poor data quality make it difficult to characterize many reservoirs. For reservoirs that have undergone waterflooding, production and injection data are a reliable source of information from which injector-to-producer connections can be inferred. In this research, we use well locations, injection and production rate data and well fractional flow values to develop a reservoir-scale network model. A Voronoi mesh divides the reservoir into a number of node volumes each of which contains a well. Bonds connect each of the nodes with conductance values that must be inferred from the rate data. An inverse problem is formulated …


Geodatabase-Assisted Storm Surge Modeling, Sait Ahmet Binselam Jan 2013

Geodatabase-Assisted Storm Surge Modeling, Sait Ahmet Binselam

LSU Doctoral Dissertations

Tropical cyclone-generated storm surge frequently causes catastrophic damage in communities along the Gulf of Mexico. The prediction of landfalling or hypothetical storm surge magnitudes in U.S. Gulf Coast regions remains problematic, in part, because of the dearth of historic event parameter data, including accurate records of storm surge magnitude (elevation) at locations along the coast from hurricanes. While detailed historical records exist that describe hurricane tracks, these data have rarely been correlated with the resulting storm surge, limiting our ability to make statistical inferences, which are needed to fully understand the vulnerability of the U.S. Gulf Coast to hurricane-induced storm …


Characterization And Uncertainty Analysis Of Siliciclastic Aquifer-Fault System, Ahmed Saad Elshall Jan 2013

Characterization And Uncertainty Analysis Of Siliciclastic Aquifer-Fault System, Ahmed Saad Elshall

LSU Doctoral Dissertations

The complex siliciclastic aquifer system underneath the Baton Rouge area, Louisiana, USA, is fluvial in origin. The east-west trending Baton Rouge fault and Denham Springs-Scotlandville fault cut across East Baton Rouge Parish and play an important role in groundwater flow and aquifer salinization. To better understand the salinization underneath Baton Rouge, it is imperative to study the hydrofacies architecture and the groundwater flow field of the Baton Rogue aquifer-fault system. This is done through developing multiple detailed hydrofacies architecture models and multiple groundwater flow models of the aquifer-fault system, representing various uncertain model propositions. The hydrofacies architecture models focus on …


Fabrication And Characterization Of A Polymeric Nanofluidic Device For Dna Analysis, Jiahao Wu Jan 2013

Fabrication And Characterization Of A Polymeric Nanofluidic Device For Dna Analysis, Jiahao Wu

LSU Doctoral Dissertations

The growing needs for cheaper and faster sequencing of long biopolymers such as DNA and RNA have prompted the development of new technologies. Among the novel techniques for analyzing these biopolymers, an approach using nanochannel based fluidic devices is attractive because it is a label-free, amplification-free, single-molecule method that can be scaled for high-throughput analysis. Despite recent demonstrations of nanochannel based fluidic devices for analyzing physical properties of such biopolymers, most of the devices have been fabricated in inorganic materials such as silicon, silicon nitride and glass using expensive high end nanofabrication techniques such as focused ion beam and electron …


Electrophoretic Deposition Of Carbon Nanotubes On Silicon Substrates, Anirban Sarkar Jan 2013

Electrophoretic Deposition Of Carbon Nanotubes On Silicon Substrates, Anirban Sarkar

LSU Doctoral Dissertations

This dissertation research describes the feasibility study and investigation of Electrophoretic Deposition (EPD) of carbon nanotubes (CNTs) for applications in semiconductor research. In recent years, the EPD technique has been considered as an economical, room temperature, solution based wet coating technique for thin and thick CNT films on arbitrary substrates. In this study, fabrication of uniform coatings of acid-treated CNTs has been pursued on bare silicon substrates by EPD from aqueous and organic suspensions. Research endeavors are extended to examine EPD of CNTs on silicon substrates with various surface coatings such as metal (aluminum), insulator layers (silicon dioxide and silicon …


Designing A Cost Effective Microalgae Harvesting Strategy For Biodiesel Production With Electrocoagulation And Dissolved Air Flotation, Adam James Dassey Jan 2013

Designing A Cost Effective Microalgae Harvesting Strategy For Biodiesel Production With Electrocoagulation And Dissolved Air Flotation, Adam James Dassey

LSU Doctoral Dissertations

Microalgal harvesting strategies for biodiesel production have been a major setback in the industry with high energy estimates of $3400/ton biomass by centrifugation. The present study utilized effective mass and energy balances to reduce these large operating costs. The energy for Stage 1 centrifugation was reduced by 82% when harvesting 28.5% of biomass at 18 L/min as opposed to 95% harvesting at 1 L/min. This strategy was further confirmed using electrocoagulation (EC) with Nannochloris and Dunaliella algae with perforated aluminum and iron electrodes at low (< 6 mg/L) metal ion concentrations. Despite 20% lower harvesting efficiencies, the iron electrodes were more energy and cost efficient with operating costs less than $0.03/L oil when flocculating and settling Nannochloris and Dunaliella cultures. Furthermore, a continuous multistage algae harvester using EC and dissolved air flotation (DAF) for Stage 1 harvesting and centrifugation for Stage 2 dewatering was designed. It was determined throughout the testing that greater EC costs for improved harvesting efficiencies were necessary to offset the large energy requirements of the DAF. The multistage system dewatered a low density (100 mg/L) Nannochloris to 20% solids for a final energy requirement of 1.536 kWh/kg algae ($138/ton). Using the data collected from this research and existing literature, a life cycle analysis was assembled to judge the sustainability of microalgal biofuels in Louisiana. High and low energy estimates for culturing (mixing, CO2, nutrients), harvesting, lipid extraction and energy conversion were compared with the current research. Scaling the EC/DAF system for a full size facility was expected to reduce the harvesting costs to 1.133 kWh/kg algae, resulting as $0.44/L oil for a culture with 20% lipids. Despite this improvement in harvesting costs, the production of algal for the sole purpose of biodiesel was not economically viable. Considering a system with a growth rate of 15 g/m2/day and lipid content of 20%, the energy inputs exceeded the outputs from biodiesel production by 36% under the most ideal conditions. However, incorporating additional revenue through wastewater treatment and biogas production from residual biomass could improve sustainability and profitability of algal biodiesel to an 18.5% energy surplus at its current state.


Time-Variant Performance Assessment And Improvement Of Existing Bridges, Miao Xia Jan 2013

Time-Variant Performance Assessment And Improvement Of Existing Bridges, Miao Xia

LSU Doctoral Dissertations

The serviceability and safety of buildings and bridges are expected to be maintained within a reasonable safety level throughout their lifetimes. However, the increase of the applied loads and degradation of structural performances reduce the safety of these structures over time. Therefore, the performance assessment of existing bridges with reliability theories is a worldwide problem in civil infrastructure systems. Theoretically, the bridge reliability, usually expressed by a reliability index, is quantified by comparing the structural capacity (R) with the load effects (Q), using the predefined limit state functions. A limit state function is a mathematical description of a boundary between …


Finite Element Modeling Of Hot-Mix Asphalt Performance In The Laboratory, Hao Ying Jan 2013

Finite Element Modeling Of Hot-Mix Asphalt Performance In The Laboratory, Hao Ying

LSU Doctoral Dissertations

The theoretical investigation of Hot-Mix Asphalt (HMA) response in the dynamic modulus and the semi-circular bending (SCB) laboratory test procedures is necessary to understand the influence of various design parameters on the performance of the mix. In addition, laboratory tests such as the dynamic complex modulus assume that this material can be dealt with as a homogeneous material while overlooking the particulate nature of this composite. The ultimate goal of this study is to develop an advanced theoretical framework, based on three-dimensional (3D) finite element (FE) methods and digital image analysis techniques to describe the behavior of HMA in two …


Thermal Cycling And Thermal Radiation Performances Of Novel Thermal Barrier Coatings, Li Wang Jan 2013

Thermal Cycling And Thermal Radiation Performances Of Novel Thermal Barrier Coatings, Li Wang

LSU Doctoral Dissertations

Thermal barrier coatings (TBCs) play an important role in protecting the superalloy components from the hot gas stream in gas-turbine engines. Driven by the higher inlet temperature of modern gas turbine engines for higher efficiency and less harmful gas emission, exploration of TBC new materials and thermal radiation effects of TBCs have attracted more attentions recently. In this study, thermochemical compatibility of Gd2Zr2O7 (GZ) and yttria-stabilized-zirconia (YSZ) at 1300 ºC was investigated. Single, double and three ceramic-layered GZ based TBCs were prepared and their thermal cycling properties were performed under different thermal conditions. Thermochemical compatibility investigation showed that YSZ tended …


Micro & Nano Scale Mechanical Testing And Assembly With Applications To Metal Based Microsystems, Ke Chen Jan 2013

Micro & Nano Scale Mechanical Testing And Assembly With Applications To Metal Based Microsystems, Ke Chen

LSU Doctoral Dissertations

Metal-based high-aspect-ratio microscale structures (HARMS) are fundamental building blocks for functional metallic micro devices. This dissertation focuses on addressing several problems in fabrication and assembly of metal based microchannel devices. First, the materials’ responses to mechanical deformation at micro & nano scales, namely the mechanical “size effect”, have been explored by molding single crystal Al with long rectangular diamond punches and long wedge shaped indenters. It is noticed that the contact pressure of rectangular punches pressed into single crystal Al strongly depends on the punch width, while that of long wedge shaped indenters depends on the included wedge angle. We …


Bioremediation Of Chlorinated Ethanes And Ethenes In Vertical Flow Engineered Wetland Systems, Christopher Akudo Jan 2013

Bioremediation Of Chlorinated Ethanes And Ethenes In Vertical Flow Engineered Wetland Systems, Christopher Akudo

LSU Doctoral Dissertations

Sustainable treatment of chlorinated ethanes and ethenes contaminated groundwater using vertical flow engineered wetland systems were investigated in microcosm and column studies. Experiments on environmental and biogeochemical factors that affect system performance were conducted, and a numerical model involving advection, sorption, and sequential biodegradation was developed to describe the fate and transport of the contaminants of concern in the treatment wetland bed. 1,1-dichloroethane (1,1-DCA) and cis-1,2-dichloroethene (cis-1,2-DCE) were used as the chemicals of interest. The presence of cis-1,2-DCE inhibited dechlorination of 1,1-DCA but cis-1,2-DCE dechlorination was not affected by the presence of 1,1-DCA. Simulation runs showed that the treatment bed …


Nanoindentation Characterization Of Clay Minerals And Clay-Based Hybrid Bio-Geomaterials, Rohit Raj Pant Jan 2013

Nanoindentation Characterization Of Clay Minerals And Clay-Based Hybrid Bio-Geomaterials, Rohit Raj Pant

LSU Doctoral Dissertations

Layered hydrous aluminosilicates are key constituent minerals in rocks, soils, and other parts of the Earth crust. Understanding mechanical properties of these aluminosilicates is crucial for seismic study, stability of parent rocks and geomaterials, and for geophysical subsurface exploration. Recently, growing prospects of clay based nanocomposites have renewed further interest in understanding the fundamental elastic and plastic properties of hydrous aluminosilicates. Their distinct, nanoscale layered crystal structure is known to result in anisotropic responses to loading, however, owing to their tiny sizes; it is a significant challenge to determine the anisotropic properties. There is a little data available in the …


Topology And Shape Optimization Of Hydrodynamically–Lubricated Bearings For Enhanced Load-Carrying Capacity, Mohammad Fesanghary Jan 2013

Topology And Shape Optimization Of Hydrodynamically–Lubricated Bearings For Enhanced Load-Carrying Capacity, Mohammad Fesanghary

LSU Doctoral Dissertations

Bearings are basic and essential components of nearly all machinery. They must be designed to work under different loads, speeds, and environments. Of all the performance parameters, load-carrying capacity (LCC) is often the most crucial design constraint. The objective of this research is to investigate different design methodologies that significantly improve the LCC of liquid-lubricated bearings. This goal can be achieved by either altering the surface texture or the bearing geometrical configuration. The methodology used here is based on mathematical topological/shape optimization algorithms. These methods can effectively improve the design performance while avoiding time-consuming trial-and-error design techniques. The first category …


Optimizing Light Requirements And Dilution Rates For Maximizing Algal Cell Growth And Lipid Content For Biofuel Feedstock Production, Beatrice Gabriela Terigar Jan 2013

Optimizing Light Requirements And Dilution Rates For Maximizing Algal Cell Growth And Lipid Content For Biofuel Feedstock Production, Beatrice Gabriela Terigar

LSU Doctoral Dissertations

There is a rapidly growing interest in the potential of microalgae as feedstock for the next generation of biofuels. The current study was designed to meet the following objectives: (1) Investigate the interdependence among cell density, biomass and lipid productivity to maximize feedstock production from outdoor cultures; (2) Investigate the effect of cycling high-intensity lights to identify optimum Dark:Light (D/L) ratios, which can be effectively used by researchers to maximize aerial biomass productivities; (3) Develop a deterministic model to simulate the biomass productivity in an continuous-flow bioreactor at various hydraulic retention times. Results indicated that variation in HRTs has a …


Molecular Dynamics Of Ionic Liquids In Nanoporous Electrodes, Nav Nidhi Rajput Jan 2013

Molecular Dynamics Of Ionic Liquids In Nanoporous Electrodes, Nav Nidhi Rajput

LSU Doctoral Dissertations

Molecular dynamics simulations were performed to investigate structural, dynamical and electrical properties of ionic liquids (ILs) confined inside different nanoporous materials. These systems have potential uses in environmental and energy applications. The main goal is to understand how these IL properties are affected by a) characteristics of nanoporous materials such as chemical nature of the pore walls (e.g., carbon, titania), pore size and pore morphology, and b) characteristics of electrolyte, such as amount of IL inside the pores (pore loading) and concentration of organic solvent, in the case of mixtures of ILs with organic solvents. The results obtained in this …


Size Kinetics And Mechanics Of Clay-Biopolymer Flocs, Hang Yin Jan 2013

Size Kinetics And Mechanics Of Clay-Biopolymer Flocs, Hang Yin

LSU Doctoral Dissertations

The suspended cohesive sediments, mostly clay minerals with negative surface charges, usually interact through an array of intermolecular/surface forces (e.g., Coulomb force, van der Waals attractions, and hydrogen bonding) with waterborne organic matter (e.g., exopolymers) and dissolved salts, resulting in fractal, tenuous, and hybrid organic-inorganic flocs or “marine snow”. A pilot and systematic laboratory and theoretical work have been conducted towards a synthetic nanoscale understanding of the flocculation kinetics and mechanics of the clay-exopolymer micro-sized flocs. This systematic study has achieved two impressive objectives: (1) the effect of exopolymer polarity and concentration on the particle size kinetics of clay-exopolymer mixtures …


Fe(Iii)2o3 Nanoparticle Mediated Molecular Growth And Soot Particle Inception From The Oxidative Pyrolysis Of 1-Methylnaphthalene, Michael Paul Herring Jan 2013

Fe(Iii)2o3 Nanoparticle Mediated Molecular Growth And Soot Particle Inception From The Oxidative Pyrolysis Of 1-Methylnaphthalene, Michael Paul Herring

LSU Doctoral Dissertations

The potential for Fe(III)2O3 nanoparticles to participate in the molecular growth and particle inception of soot from 1-methylnapthalene (1-MN) was studied in a dual-zone, high-temperature flow reactor. An iron substituted, dendrimer template was oxidized in the Zone 1 reactor to generate ~5nm Fe(III)2O3 nanoparticles, that were continually seeded to a high sooting 1-MN fuel under oxidative pyrolysis conditions. The Fe(III)2O3 nanoparticles could then influence the otherwise gas-phase reactions of 1-MN. Increased PAH formation, soot number density, soot mass yield, and soot radical intensity were observed as a result of Fe(III)2O3 nanoparticle introduction prior to soot inception. Low Temperature Matrix Isolation-Electron …


A Metaheuristic-Based Simulation Optimization Framework For Supply Chain Inventory Management Under Uncertainty, Qinglin Duan Jan 2013

A Metaheuristic-Based Simulation Optimization Framework For Supply Chain Inventory Management Under Uncertainty, Qinglin Duan

LSU Doctoral Dissertations

The need for inventory control models for practical real-world applications is growing with the global expansion of supply chains. The widely used traditional optimization procedures usually require an explicit mathematical model formulated based on some assumptions. The validity of such models and approaches for real world applications depend greatly upon whether the assumptions made match closely with the reality. The use of meta-heuristics, as opposed to a traditional method, does not require such assumptions and has allowed more realistic modeling of the inventory control system and its solution. In this dissertation, a metaheuristic-based simulation optimization framework is developed for supply …