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Full-Text Articles in Engineering
Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen
Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen
LSU Doctoral Dissertations
The Mississippi River Delta is threatened by a growing pressure to support large human populations in the United States both with food production, navigation systems, and urban development in the Mississippi River Basin. Nitrate-nitrogen load in the Mississippi River, up to 100 Tg N yr-1 from agricultural and urban runoff, leads to phytoplankton blooms and hypoxia across the Louisiana continental shelf, creating dead zones of low dissolved oxygen threatening a significant commercial fishery. Along the coast and river corridors, floodplain ecosystems have the capacity to retain and remove nitrate. This dissertation explores the role of productive, actively growing coastal …
Numerical Modeling Of Wave Dynamics And Sediment Transport Near The Mississippi Birdfoot Delta And Barataria Estuary, Soroush Sorourian
Numerical Modeling Of Wave Dynamics And Sediment Transport Near The Mississippi Birdfoot Delta And Barataria Estuary, Soroush Sorourian
LSU Doctoral Dissertations
The Barataria Basin is a large estuarine system in Southeastern Louisiana, connected to the Gulf of Mexico through a number of inlets, the most important of which is the Barataria Pass. This research examines, during April-June 2010 including both cold front passage and calm summer-time wind regimes, the wave dynamics in this basin and in its major inlets, morphological evolution near the Barataria Pass, and the budgeting and dispersal of the Mississippi River sediment in the birdfoot delta region. An unstructured grid, terrain following, high resolution coupled FVCOM-SWAVE-SED model is employed and validated in this study. The numerical model results …
Thermo-Catalytic Upgrading Of Pyrolysis Vapors Using Electromagnetic Heating, Pranjali Devidas Muley
Thermo-Catalytic Upgrading Of Pyrolysis Vapors Using Electromagnetic Heating, Pranjali Devidas Muley
LSU Doctoral Dissertations
Electromagnetic heating offers several advantages such as rapid heating rates, accurate temperature control and energy efficiency over conventional reactors. The goal of this study was to design an effective and energy efficient catalytic reactor for pyrolysis vapor upgrading. An induction based catalytic reactor was designed for upgrading of pyrolysis vapors. The effect of catalyst bed temperatures (290°, 330° and 370°C) and biomass to catalyst ratios of 1, 1.5 and 2 was studied. The results were compared to conventional heating reactor. Induction heating reactor performance exceeded that of conventional heater. The biomass to catalyst ratio of 2 in combination with the …
Numerical Investigation Of Cryopreserved Zebrafish Sperm Cell Activation In Microchannels, Thomas Foster Scherr
Numerical Investigation Of Cryopreserved Zebrafish Sperm Cell Activation In Microchannels, Thomas Foster Scherr
LSU Doctoral Dissertations
This aim of this research project is to probe the activation process of zebrafish spermatozoa. Zebrafish are a model species for biological engineering applications, and the cryopreservation of their reproductive cells allows for inexpensive cataloging and maintenance of valuable biological material. Evaluation of cryopreservation protocols for aquatic sperm cells is typically accomplished by motility analysis after subjecting cells to a cryopreservation treatment. In zebrafish sperm cells, motility is initiated when cells come into contact with a hypo-osmotic environment. Subsequent activation analysis is currently done manually and brings with it an inherent difficulty and error. This process is slow and not …
Thermal Field Investigations And Applications To Integral Abutment Bridges With Frp Panels, Bo Kong
Thermal Field Investigations And Applications To Integral Abutment Bridges With Frp Panels, Bo Kong
LSU Doctoral Dissertations
Expansion joints are often considered as one of the most vulnerable elements affecting the sustainability of traditional jointed bridges. Over the past several decades, a new type of integral abutment bridge (IAB) has been proposed, where the joints are eliminated at the abutments and/or along the length of the bridges. Although with wide acceptances, the IABs have not been largely applied in practice. Many arguments are unsettled and there are no national design guidelines currently. Among all, the thermal behavior is one of the most concerned issues, and that, to a large extent, limits the maximum length of IABs that …
Flow And Distribution Of Water In Fractional Wettability Unsaturated Porous Media, Zaydoun Turkey Abusalem
Flow And Distribution Of Water In Fractional Wettability Unsaturated Porous Media, Zaydoun Turkey Abusalem
LSU Doctoral Dissertations
In recent years, interest in fluid flow and transport in the unsaturated zone has gained more attention, due to growing concerns that the quality of the subsurface environment is adversely affected by agricultural, industrial, and municipal activities. The wettability properties (e.g., water repellency) of soil in the unsaturated zone play an important role in determining fluid movement and ultimate distributions. A number of studies have shown that preferential flow and spatially variable moisture content is likely to occur in water repellant soils. Development of appropriate constitutive relations for numerical modeling becomes even more difficult in systems that contain water repellant …
Numerical Modeling Of Strain Localization In Granular Materials Using Cosserat Theory Enhanced With Microfabric Properties, Mustafa Alsaleh
Numerical Modeling Of Strain Localization In Granular Materials Using Cosserat Theory Enhanced With Microfabric Properties, Mustafa Alsaleh
LSU Doctoral Dissertations
Finite element solution in the updated Lagrangian frame is used to investigate the strain localization phenomenon "shear bands" in granular materials. The micro-polar theory was used as the mathematical foundation for the continuum formulations. A laboratory testing results are used for verification and comparison with the numerical simulation. Silica sand and glass beads with different shape indices, size and surface roughness were tested under biaxial and triaxial loading conditions to investigate the physics of the problem. The shape non-uniformity and the irregular surface roughness of the grains were studied carefully to evaluate their effect on shear band characteristics. To this …