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“Hydraulic Fracturing Efficiency In The Olmos Sand Formation”, Lauren N. Fogarty Dec 2010

“Hydraulic Fracturing Efficiency In The Olmos Sand Formation”, Lauren N. Fogarty

Honors Theses

No abstract provided.


Catalytic Oxidative Desulfurization Of A Model Diesel, Dongxing Liu Jan 2010

Catalytic Oxidative Desulfurization Of A Model Diesel, Dongxing Liu

LSU Major Papers

An analysis of heterogeneous oxidation catalysts was performed to determine the activities and optimal operating conditions for the multiphase oxidative desulfurization (ODS) reactions, using a model diesel. Catalysts studied included well-characterized Pd on Al2O3 and activated carbon supports, and carbon-supported Mo2C and W2C, which were prepared by temperature programmed reaction. Several other typical oxidation catalysts were also examined. The model diesel consisted of ~1 wt% sulfur compounds (thiophene and dibenzothiophene) with appropriate amounts of aliphatic, alkylaromatic and N-heterocyclic compounds to simulate a raw number 2 diesel. With oxygen as the oxidant in ODS reactions of this model diesel (70-90ºC, 0.8-1.8 …


Effect Of Management Awareness Of Safety Climate Concept On Organizational Safety Climate, Christopher Michael Holzner Jan 2010

Effect Of Management Awareness Of Safety Climate Concept On Organizational Safety Climate, Christopher Michael Holzner

LSU Master's Theses

Safety research and practice have shifted focus away from accident rates and accident causal information to a more proactive approach that may predict organizational safety trends. This proactive approach involves the concept of an organizational safety culture and the use of surveys to measure organizational safety climate or „snapshot‟ of the organizational safety culture. Surveys were administered to line workers, supervisors, and managers at a modular home manufacturing company before and after safety climate information was presented to supervisors and managers in an attempt to measure the effect of the supervisors‟ and managers‟ increased awareness of the factors that define …


Value-Added Processing Of Rice And Rice By-Products, Rebecca C. Schramm Jan 2010

Value-Added Processing Of Rice And Rice By-Products, Rebecca C. Schramm

LSU Doctoral Dissertations

World competition has encouraged United States rice farmers and rice mills to be efficient in farming and production practices. Efforts to augment economic competitiveness include development of new varieties, improvements in milling practices, and identification of uses for rice products and by-products. The research detailed in this dissertation adds to the body of knowledge in milling practices and identification of uses for rice bran. To improve the prediction of milled rice quality at industrial scale, correlations for milling quality among laboratory, pilot, and industrial scale mills were identified for Clearfield 161. Final industrial product whiteness was ten points higher than …


Transit-Based Emergency Evacuation Modeling With Microscopic Simulation, Hana H. Naghawi Jan 2010

Transit-Based Emergency Evacuation Modeling With Microscopic Simulation, Hana H. Naghawi

LSU Doctoral Dissertations

Several recent mass evacuations, including those in advance of Hurricane Katrina in New Orleans and Hurricane Rita in Houston, have demonstrated the effects of limited planning for carless populations. The lack of planning left a significant portion of the mobility-limited population of both these cities unable to flee in advance of the storms. Since 2005 however, both of these cities (as well as others across the United States) have developed transit assisted mass evacuation plans at various levels of detail. Since these plans are relatively recent and do not have a history of experience on which to base their performance, …


Experimental And Numerical Analysis Of Fuel Cells, Abul Bashar Mahmud Hasan Jan 2010

Experimental And Numerical Analysis Of Fuel Cells, Abul Bashar Mahmud Hasan

LSU Doctoral Dissertations

Fuel Cells are attractive power source for use in electronic applications. Physical phenomena (water generation, saturation effect in fuel cell, poisoning, and thermal stress) are studied that governs the operation of a Proton Exchange Membrane Fuel Cell (PEMFC) and Solid Oxide Fuel cell (SOFC). Additionally, experimental studies and numerical simulations on PEMFC gas flow channel, the determination of the impact of the single channel fuel cell are presented. Furthermore, preliminary study is done for the application of APS (Air Plasma Spray) to SOFC and adhesion of anode and cathode with electrolytes for the determination of parameters involved in manufacturing the …


Antioxidant Nanoparticles As Delivery Systems, Carlos Ernesto Astete R. Jan 2010

Antioxidant Nanoparticles As Delivery Systems, Carlos Ernesto Astete R.

LSU Doctoral Dissertations

The goal of the study was to develop antioxidant polymeric nanoparticles as a new delivery system for food and pharmaceutical applications. Natural antioxidants like alpha-tocopherol, vitamin C, and carnosine, are responsible to protect biological systems against free radicals attack. The conjugation of vitamin C-vitamin E (EC) and alpha-tocopherol-carnosine (VECAR) were performed to obtain antioxidant surfactants which were used for polymeric nanoparticle synthesis. The surfactant made of á-tocopherol (vitamin E) and ascorbic acid (vitamin C) of antioxidant properties dubbed as EC was used to make poly(lactic-co-glycolic) acid (PLGA) nanoparticles. Self-assembled EC nanostructures and PLGA-EC nanoparticles were made by nanoprecipitation, and the …


Studies Of Hydrophobic Organic Pollutant Interactions With Cyclodextrin: Implication For Groundwater Remediation, Heng Gao Jan 2010

Studies Of Hydrophobic Organic Pollutant Interactions With Cyclodextrin: Implication For Groundwater Remediation, Heng Gao

LSU Doctoral Dissertations

Henry’s Law constants of several common, subsurface hydrophobic organic pollutants (HOPs) including trichloroethylene (TCE), perchloroethylene (PCE) and benzene, toluene, ethylbenzene and o-xylene (BTEX), were measured over a range of temperatures (35, 45, 55 and 65°C) and cyclodextrin (CD) concentrations (0, 10, 20, 50 and 100 g L-1). In aqueous CD solutions, Henry’s constant values decrease by a power law relationship with increasing CD concentration due to an apparent solubility enhancement caused by HOP partitioning to the hydrophobic cavity of CD molecules. The temperature dependence of air-water partitioning under the influence of CD was well described by the van’t Hoff equation …


Study Of Microstructure Effect On The Thermal Properties Of Yttria-Stabilized-Zirconia Thermal Barrier Coatings Made By Atmospheric Plasma Spray And Pressing Machine, Monica Bohorquez De Silva Jan 2010

Study Of Microstructure Effect On The Thermal Properties Of Yttria-Stabilized-Zirconia Thermal Barrier Coatings Made By Atmospheric Plasma Spray And Pressing Machine, Monica Bohorquez De Silva

LSU Doctoral Dissertations

Thermal barrier coatings (TBCs) are used in gas turbine engines to achieve a higher working temperature and thus lead to better efficiency. Yttria-Stabilized-Zirconia (YSZ), a material with low thermal conductivity, is commonly used as the top coat layer to provide the thermal barrier effect. In this dissertation the thermo-physical properties of a variety of TBCs samples made out of different fabrication techniques were investigated and compared. The first set of samples was fabricated using a pressing machine device to fabricate 0.5 inch diameter disk shaped YSZ-Al2O3 samples. The YSZ-Al2O3 powder mixture was made of 0, 1, 2, 3, 4 and …


Dynamic Trip Distribution Models For Hurricane Evacuation, Guangxiang Cheng Jan 2010

Dynamic Trip Distribution Models For Hurricane Evacuation, Guangxiang Cheng

LSU Doctoral Dissertations

The dissertation presents several methods to estimate time-dependent origin-destination (O-D) trip tables for hurricane evacuation using survey data from hurricane Floyd in South Carolina in 1999. A static disaggregate destination choice model in multinomial logit form was developed considering household characteristics, hurricane threats, and destination socioeconomic and demographic characteristics. Models were developed for persons evacuating to friends or relatives, and hotels or motels separately. None of the household characteristics of evacuees were found to be significant in distinguishing destination choice but destination characteristics were. The model was tested by comparing the observed destination choices with predicted values via trip length …


Supercritical Pyrolysis Of N-Decane, Sean Bagley Jan 2010

Supercritical Pyrolysis Of N-Decane, Sean Bagley

LSU Doctoral Dissertations

Fuels used in future generations of high-speed jet aircraft will be required to take on increasing heat loads in their role as the primary coolant for the absorption of waste heat from the engine. As a consequence, the hydrocarbon fuels will be exposed to elevated temperatures and pressures prior to their use as fuels, conditions which are beyond the critical point of the fuel and which lead to the formation of carbonaceous solid deposits in the pre-combustion environment.

Deposition of solids causes reduced engine performance and eventual failure, so understanding the mechanisms by which thermally stressed hydrocarbons become solids is …


Influence Of Unstable Soil Movement On Pile-Founded Concrete Floodwalls And A Resulting Design Methodology, Richard James Varuso Jan 2010

Influence Of Unstable Soil Movement On Pile-Founded Concrete Floodwalls And A Resulting Design Methodology, Richard James Varuso

LSU Doctoral Dissertations

Efforts are underway in the New Orleans area to raise the elevations of its levee system to combat the effects of hurricane storm surge. When complete, the majority of the system will be comprised of a combination of levees, sheet pile I-Walls, floodgates, and pile-supported concrete floodwalls, commonly referred to as T-Walls. Given the magnitude of the hydrostatic forces associated with storm surge, global instability is failure mechanism that must be considered in the design of T-Walls. In the past, it was assumed that these forces would be resisted by the T-Wall’s sheet pile cut-off wall. Recent literature review and …


Identifying And Quantifying Factors Affecting Traffic Crash Severity In Louisiana, Hong Zhang Jan 2010

Identifying And Quantifying Factors Affecting Traffic Crash Severity In Louisiana, Hong Zhang

LSU Doctoral Dissertations

This study was conducted to identify and quantify the factors affecting highway crash severity in Louisiana. Three candidate models were fit to the crash data to compare their performance and the Ordered Mixed Logit (OML) model was selected as the crash severity prediction model of choice. The factors contributing to crash severity identified by the OML model are: age and gender of the driver, vehicle speed, whether alcohol played a role in the crash, whether seatbelts were used, whether the driver was ejected from the vehicle, whether the crash was a head-on collision, whether an airbag was deployed, and whether …


X-Ray Absorption Spectroscopy Applied To Mixed-Metal Iron-Based Fischer-Tropsch Catalysts, Andrew Allen Campos Jan 2010

X-Ray Absorption Spectroscopy Applied To Mixed-Metal Iron-Based Fischer-Tropsch Catalysts, Andrew Allen Campos

LSU Doctoral Dissertations

Synthetic fuels derived from methane, coal or biomass are essential in addressing future transportation fuel demands which are expected to exceed petroleum-derived capacities. The Fischer-Tropsch synthesis (FTS) is the most studied technique for the conversion of coal or biomass-derived syngas into transportation fuels. Fe-based catalysts are typically used for the FTS of biomass and/or coal-derived syngas due to: the relatively low cost of iron, water-gas shift activity, and low methane selectivity at industrial FTS conditions. Fe/Cu/SiO2 Fischer-Tropsch catalysts promoted with Cr, Mn, Mo, W, or Zr were studied in-situ, using Fe K-edge TPR XANES (temperature programmed reduction X-ray absorption near-edge …


Modeling And Multiresolution Characterization Of Micro/Nano Surface For Novel Tailored Nanostructures, Rajib Mukherjee Jan 2010

Modeling And Multiresolution Characterization Of Micro/Nano Surface For Novel Tailored Nanostructures, Rajib Mukherjee

LSU Doctoral Dissertations

Nanofabrication is state of the art technology. Various chemical, mechanical, biochemical and semiconductor products have characteristics controlled by the nanostructures of the surface and interphase. Surface microscopic imaging is generally used to capture different surface features. By properly analyzing the surface image, valuable information regarding manufacturing process and product performance can be extracted. While microscopy measurements can offer very accurate qualitative information about surface features, for many applications, it is critical to obtain a quantitative description of the surface morphology. Various statistical features can be used to characterize the surface in quantitative way. Such an analysis can be done by …


Friction And Wear At Elevated Velocities, Adam Lodygowski Jan 2010

Friction And Wear At Elevated Velocities, Adam Lodygowski

LSU Doctoral Dissertations

Severe contact stress problems generate high temperature and create thermomechanical gouging and wear due to high velocity sliding between contacting materials. The major consideration is to develop an experimental and theoretical model for the material constitutive behavior in order to better characterize and predict the internal failure surroundings the gouging and wear events and understand the physical behavior of high speed contact environment. An enhancement of an existing tribometer device developed by Philippon et al. [2004] is made up of a dynamometer ring and a load sensor that allows to apply an apparent normal force on specimens and measure frictional …


Dynamic Model Of Ecological Factors Impacting The Gulf Of Mexico Dead Zone, Jimmie Arnold Brumfield Ii Jan 2010

Dynamic Model Of Ecological Factors Impacting The Gulf Of Mexico Dead Zone, Jimmie Arnold Brumfield Ii

LSU Doctoral Dissertations

The industrial agriculture complex of the Mississippi River Drainage Basin has the positive effect of feeding more individuals with less land via the use of chemical nutrients, pesticides and drainage. The negative effects of the agricultural nutrient load are carried by the Mississippi River to the Gulf of Mexico. After the flood of 1927 the Flood Control Act of 1928 began changing the Mississippi River into a navigation and flood control project. While successful, the river was turned into a channel where nutrient input was discharged into the Gulf of Mexico. Nitrogen compounds discharged from the Mississippi are claimed to …


Transient Study Of The Wetting Films In Porous Media Using 3d X-Ray Computed Micro-Tomography: Effect Of Imbibition Rate And Pore Geometry, Pradeep Bhattad Jan 2010

Transient Study Of The Wetting Films In Porous Media Using 3d X-Ray Computed Micro-Tomography: Effect Of Imbibition Rate And Pore Geometry, Pradeep Bhattad

LSU Doctoral Dissertations

Imbibition in porous media is governed by the complex interplay between viscous and capillary forces, pore structure and fluid properties. Understanding and predicting imbibition is important in many natural and engineered applications; it affects the efficiency of oil production operations, the moisture and contaminant transport in soil science, and the formation of defects in certain types of composite materials. Majority of the studies published on the transient imbibition behavior in a porous medium were conducted in the simplified 2D transparent micromodels or the 2D projection visualization (X-ray or visible light) of the 3D porous medium. However, the pore level transient …


Probabilistic Models For Short Term Traffic Conditions Prediction, Yan Qi Jan 2010

Probabilistic Models For Short Term Traffic Conditions Prediction, Yan Qi

LSU Doctoral Dissertations

Accurate short-term prediction of traffic condition on freeways and major arterials has become increasingly important because of its vital role in traffic management functions and various trip decisions. Given the dynamic nature of freeway traffic, this study proposed two stochastic model approaches, Hidden Markov Model (HMM) and One-Step Stochastic Model, for short-term traffic prediction during peak periods. The data used in the study are real-time traffic monitoring data gathered over 6 years on a 40-mile segment of Interstate-4 in Orlando, Florida. Both approaches are based on the traffic state transition probabilities. The HMM approach defines traffic states in a two …


Designing A Whey Protein Based Material As A Scaffold For Bone Regeneration, Mia Dvora Jan 2010

Designing A Whey Protein Based Material As A Scaffold For Bone Regeneration, Mia Dvora

LSU Doctoral Dissertations

A novel gel material was designed and optimized for use as a bone tissue regeneration scaffold. Whey protein isolate (WPI), the primary component of the material, underwent considerable testing for conformity to a set of known material characteristics required for application in bone regeneration. WPI gels of different compositions were fabricated by thermally inducing gelation of high-concentration protein suspensions, and characterized for compressive strength and modulus, hydration swelling and drying properties, mechanical behavior change due to polysaccharide additives, and intrinsic pore network structure. The gels were also tested for their compatibility with MC3T3-E1 cells, and interactions such as cell adhesion, …


Integrating Bioprocesses Into Industrial Complexes For Sustainable Development, Debalina Sengupta Jan 2010

Integrating Bioprocesses Into Industrial Complexes For Sustainable Development, Debalina Sengupta

LSU Doctoral Dissertations

The objective of this research is to propose, develop and demonstrate a methodology for the optimal integration of bioprocesses in an existing chemical production complex. Chemical complex optimization is determining the optimal configuration of chemical plants in a superstructure of possible plants based on economic, environmental and sustainable criteria objective function (triple bottomline) and solves a mixed integer non linear programming problem. This research demonstrated the transition of production of chemicals from non-renewable to renewable feedstock. A conceptual design of biochemical processes was converted to five industrial scale designs in Aspen HYSYS® process simulator. Fourteen input-output block models were created …


Effects Of Bondline Thickness On Nonlinear Interfacial Fracture Of Bonded Adhesive Joint, Gefu Ji Jan 2010

Effects Of Bondline Thickness On Nonlinear Interfacial Fracture Of Bonded Adhesive Joint, Gefu Ji

LSU Doctoral Dissertations

A number of existing and emerging industrial applications are dependent on layered substrates through adhesive bonding. The interfacial fracture of adhesively bonded structures is a critical issue for its extensive applications to a variety of modern industries. In the recent two decades, cohesive zone models (CZMs) have been receiving intensive attentions for fracture problems of adhesively bonded joints due to its fairly simple and accurate predictive ability. In CZMs the nonlinear interfacial fracture behaviors are described by the traction-separation laws (also referred to as cohesive laws). The cohesive laws represent the local constitutive behavior, instead of the global parameter, such …


Electrodeposited Cu-Based Catalysts For Alcohols From Co Hydrogenation And Electrodeposition Of Cuniw/Cuni Multilayered Alloys, Mayank Gupta Jan 2010

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

LSU Doctoral Dissertations

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


Experimental And Analytical Study Of The Surface Texturing Enhanced Lubrication Elements, Yifan Qiu Jan 2010

Experimental And Analytical Study Of The Surface Texturing Enhanced Lubrication Elements, Yifan Qiu

LSU Doctoral Dissertations

Surface texturing is a method that modifies the frictional surface of a nominally flat tribocomponent by shallow patterns. It is found that with added patterns to the surface of a mechanical face seal or thrust bearing, their tribological performance improves, i.e. both friction and wear rate decrease. The current research concentrates on the analysis of hydrodynamic effect responsible for the performance enhancement of the spiral groove patterns and dimples on mechanical seal-like structures and the experimental evaluation of the tribological behavior of these structures. Surface textures considered are: dimple texture and spiral groove pattern. In the research on the dimple …


Characterization Of Rock/Fluids Interactions At Reservoir Conditions, Dayanand Saini Jan 2010

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

LSU Doctoral Dissertations

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


Elastohydrodynamic Analysis Of Spur Gears Using Load-Sharing Concept: Running-In And Steady-State, Saleh Akbarzadeh Jan 2010

Elastohydrodynamic Analysis Of Spur Gears Using Load-Sharing Concept: Running-In And Steady-State, Saleh Akbarzadeh

LSU Doctoral Dissertations

Gears are widely used in industry and hence their performance is of vital importance. Under the typical operating conditions of gears, the lubricant layer formed between the teeth of the pinion and the gear cannot completely separate the surfaces and contact of asperities of the pinion and gear occurs. This case is usually referred to as mixed lubrication problem. In this research the load-sharing concept has been employed to predict the performance of the pinion-gear system. The load-sharing concept is an efficient method to solve the mixed lubrication problem and is capable to predict the thickness of the lubricant film, …


Modeling And Simulation For Shape Memory Polymer Based Self-Healing Syntactic Foam, Wei Xu Jan 2010

Modeling And Simulation For Shape Memory Polymer Based Self-Healing Syntactic Foam, Wei Xu

LSU Doctoral Dissertations

Syntactic foams, renowned for their low density and high mechanical properties, are enjoying continuing growth in various civilian and military sectors. However, like laminated composites, foam cored structures are vulnerable to impact damages and suffering from inabilities in repairing macro-scale cracks. A self-healing mechanism for structural damage is genuinely desired. A recent development in self-healing structural damage is a two-step close then heal (CTH) scheme proposed by Li and Nettles [1] and elucidated by Li and Uppu [2], by mimicking the self-healing process of human skin. This concept has been further demonstrated in Nji and Li’s work [3] that a …


Carbon Nanotube Interconnect Modeling For Very Large Scale Integrated Circuits, Yao Xu Jan 2010

Carbon Nanotube Interconnect Modeling For Very Large Scale Integrated Circuits, Yao Xu

LSU Doctoral Dissertations

In this research, we have studied and analyzed the physical and electrical properties of carbon nanotubes. Based on the reported models for current transport behavior in non-ballistic CNT-FETs, we have built a dynamic model for non-ballistic CNT-FETs. We have also extended the surface potential model of a non-ballistic CNT-FET to a ballistic CNT-FET and developed a current transport model for ballistic CNT-FETs. We have studied the current transport in metallic carbon nanotubes. By considering the electron-electron interactions, we have modified two-dimensional fluid model for electron transport to build a semi-classical one-dimensional fluid model to describe the electron transport in carbon …


Point-Of-Care Immunoassay System Using Carbon Nanotube Labels, Adeyabeba Abera Jan 2010

Point-Of-Care Immunoassay System Using Carbon Nanotube Labels, Adeyabeba Abera

LSU Doctoral Dissertations

The goal of this research was to develop enhanced signal detection mechanisms for immunosensing using carbon nanotubes (CNTs). The utilization of CNT labels for direct electrical measurement was implemented on lateral flow system and microfluidic integrated interdigitated array microelectrodes. These sensing mechanisms in simple and miniaturized system provided higher sensitivity and autonomous flow control for rapid detection aimed at point-of-care diagnostics. Specific functionalization protocols were carried out to chemically modify the surface of the CNTs for uniform dispersion and antibody conjugation in aqueous solution. Surfactant assisted dispersion of the CNTs was studied using PVP and PEG. Covalent conjugation of antibodies …


Fabrication, Characterization, Modeling And Testing Of A Nanostructured Bulk Thermoelectric Cooler, Dinesh Pinisetty Jan 2010

Fabrication, Characterization, Modeling And Testing Of A Nanostructured Bulk Thermoelectric Cooler, Dinesh Pinisetty

LSU Doctoral Dissertations

New generation micro/nano devices are emerging to monitor, control and act on living systems. Particularly, in the field of cryobiology, there is a need to monitor and control temperature at the cellular level. An important step towards achieving this aim is to fabricate a novel bulk nanostructured thermoelectric cooler (TEC). As a first step towards achieving efficient localized control of temperature in biological systems, Bismuth-telluride (Bi2Te3) and Antimony-Telluride (Sb2Te3) arrays of nanowires and nanotubes were fabricated, characterized and modeled. A thermal conductivity model originally developed by Dames and Chen for superlattice nanowires was extended to nanotubes. Based on this model …