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Modeling Intracranial Fluid Flows And Volumes During Traumatic Brain Injury To Better Understand Pressure Dynamics, Wayne W. Wakeland, James Mcnames, Mateo Aboy, D. Hollemon, Brahm Goldstein Jan 2003

Modeling Intracranial Fluid Flows And Volumes During Traumatic Brain Injury To Better Understand Pressure Dynamics, Wayne W. Wakeland, James Mcnames, Mateo Aboy, D. Hollemon, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

See additional files below for the Presentation.

We describe a computer model of intracranial pressure (ICP) dynamics that evaluates clinical treatment options for elevated ICP during traumatic brain injury (TBI). The model uses fluid volumes as primary state variables and explicitly models fluid flows as well as the resistance, compliance, and pressure associated with each intra - and extracranial compartment (arteries and arterioles, capillary bed, veins, venous sinus, ventricles, and brain parenchyma). The model evaluates clinical events and therapies such as intra - and extra-parenchymal hemorrhage, cerebral edema, cerebrospinal fluid drainage, mannitol administration, head elevation, and mild hyperventilation. The model …


Particle Trapping In Stratified Estuaries - Definition Of A Parameter Space, David A. Jay, Philip M. Orton, Thomas A. Chisholm, Douglas J. Wilson, Annika M. Fain, John Mcginity Jan 2003

Particle Trapping In Stratified Estuaries - Definition Of A Parameter Space, David A. Jay, Philip M. Orton, Thomas A. Chisholm, Douglas J. Wilson, Annika M. Fain, John Mcginity

Civil and Environmental Engineering Faculty Publications and Presentations

Estuarine turbidity maxima (ETM) retain suspended particulate matter (SPM) through advection, settling, aggregation and non-linearities in bed processes. This contribution defines for the first time a parameter space descriptive of ETM water-column particle trapping processes through a scaling analysis of the local and integral SPM balances. In the absence of long-term deposition, there are five primary parameters for the large particles or aggregates that are typically trapped. Rouse number P, the ratio of settling velocity WS of the SPM relative to the shear velocity U*, describes the material trapped in the ETM in terms of the local vertical balance between …


Environmental Management Of Waste Electrical & Electronic Equipment (Weee) In Ireland, Simon Wilkinson Jan 2003

Environmental Management Of Waste Electrical & Electronic Equipment (Weee) In Ireland, Simon Wilkinson

Theses

This thesis follows two previous studies by the Author on the calculation of theoretical WEEE arisings, and an assessment of ecodesign practices in Ireland. It has established collection trials in five different locations throughout Ireland in order to characterise and quantify WEEE arisings, and to examine outlets for collected WEEE. Overall, during the twelve months of collection at the project locations, more than 450 tonnes of WEEE was collected from the public and recycled. Within the catchments of each facility, collection rates of between 2.1 and 3.5 kg/person/year were achieved during the twelve-month trial period. With further public awareness raising …


Extraction Of A Valuable Compound From A Waste Stream For Adm Ringaskiddy, Colin G. Burkley Jan 2003

Extraction Of A Valuable Compound From A Waste Stream For Adm Ringaskiddy, Colin G. Burkley

Theses

This thesis was originally conceived as a potential Masters Degree research programme by the management of ADM Ringaskiddy as a means of maximizing throughput through the plant’s wastewater treatment facility. This facility is a major producer of citric acid using beet molasses and a fermentation process. It was proposed that removal of a compound, known as betaine, from the citric acid process waste stream would reduce the Chemical Oxygen Demand (COD) content of the waste requiring treatment before disposal. This would be achieved by using the citric acid process waste as the feedstock for a betaine extraction process. The wastewater …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 19, Number 3, January 2003, College Of Engineering And Computer Science, Wright State University Jan 2003

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 19, Number 3, January 2003, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Stochastic Game Approach To Air Operations, Ben G. Fitzpatrick, William M. Mceneaney, Istvan G. Lauko Jan 2003

Stochastic Game Approach To Air Operations, Ben G. Fitzpatrick, William M. Mceneaney, Istvan G. Lauko

Mathematics, Statistics and Data Science Faculty Works

A Command and Control (C2) problem for Military Air Operations is addressed. Specifically, we consider C2 problems for air vehicles against ground based targets and defensive systems. The problem is viewed as a stochastic game. In this paper, we restrict our attention to the C2 level where the problem may consist of a few UCAVs or aircraft (or possibly teams of vehicles); less than say, a half-dozen enemy SAMs; a few enemy assets (viewed as targets from our standpoint); and some enemy decoys (assumed to mimic SAM radar signatures). At this low level, some targets are …


Bridge Rails And Transitions For Pedestrian Protection, Nicholas R. Hiser, Ronald K. Faller, Dean L. Sicking, John R. Rohde, John D. Reid, Karla A. Polivka Jan 2003

Bridge Rails And Transitions For Pedestrian Protection, Nicholas R. Hiser, Ronald K. Faller, Dean L. Sicking, John R. Rohde, John D. Reid, Karla A. Polivka

Mid-America Transportation Center: Final Reports and Technical Briefs

It is desirable to protect pedestrians on bridges from motor vehicles. However, transition problems arise at the ends of bridges where the bridge rail, bridge rail end treatment, and pedestrian walkway compete for the limited available space. The objective of this study was to identify the most common scenarios in which the protection of pedestrians on bridges is desirable, and then to develop bridge rail and bridge rail end treatment configurations to accommodate those situations. The objective was achieved by performing a field investigation, a survey of state transportation agencies, and a literature review. Recommendations for the placement and general …


Pipeline Safety Systematic Process Needed To Evaluate Outcomes Of Research And Development Program Jan 2003

Pipeline Safety Systematic Process Needed To Evaluate Outcomes Of Research And Development Program

United States Department of Transportation: Publications

OPS distributes its R&D budget among four main areas. For example, in fiscal year 2003, the office plans to allocate its $8.7 million budget as follows:

• 46 percent ($4.0 million) to developing new technologies to prevent damage to pipelines and prevent leaks;

• 21 percent ($1.9 million) to improving technologies for operating, controlling, and monitoring the condition of pipelines;

• 19 percent ($1.7 million) to improved pipeline materials, such as materials that are resistant to damage and defects; and

• 14 percent ($1.2 million) to efforts to improve data on the location and safety performance of pipelines.

On the …


Novel Small Molecule Inhibitors Of Botulinum Neurotoxin A Metalloprotease Activity, James C. Burnett, James J. Schmidt, Robert G. Stafford, Rekha G. Panchal, Tam L. Nguyen, Ann R. Hermone, Jonathan L. Vennerstrom, Connor F. Mcgrath, Douglas J. Lane, Edward A. Sausville, Daniel W. Zaharevitz, Rick Gussio, Sina Bavari Jan 2003

Novel Small Molecule Inhibitors Of Botulinum Neurotoxin A Metalloprotease Activity, James C. Burnett, James J. Schmidt, Robert G. Stafford, Rekha G. Panchal, Tam L. Nguyen, Ann R. Hermone, Jonathan L. Vennerstrom, Connor F. Mcgrath, Douglas J. Lane, Edward A. Sausville, Daniel W. Zaharevitz, Rick Gussio, Sina Bavari

United States Army: Publications

Botulinum neurotoxins (BoNTs) are among the most lethal biological substances to have been weaponized and are listed as biodefense category A agents. Currently, no small molecule (non-peptidic) therapeutics exist to counter this threat; hence, identifying and developing compounds that inhibit BoNTs is a high priority. In the present study, a high-throughput assay was used to identify small molecules that inhibit the metalloprotease activity of BoNT serotype A light chain (BoNT/A LC). All inhibitors were further verified using a HPLC-based assay. Conformational analyses of these compounds, in conjunction with molecular docking studies, were used to predict structural features that contribute to …


Protracted Protection To Plasmodium Berghei Malaria Is Linked To Functionally And Phenotypically Heterogeneous Liver Memory Cd8+ T Cells1, Dmitri Berenzon, Robert J. Schwenk, Lisa Letellier, Mimi Guebre-Xabier, Jackie Williams, Urszula Krzych Jan 2003

Protracted Protection To Plasmodium Berghei Malaria Is Linked To Functionally And Phenotypically Heterogeneous Liver Memory Cd8+ T Cells1, Dmitri Berenzon, Robert J. Schwenk, Lisa Letellier, Mimi Guebre-Xabier, Jackie Williams, Urszula Krzych

United States Army: Publications

We previously demonstrated that protection induced by radiation-attenuated (y) Plasmodium berghei sporozoites is linked to MHC class I-restricted CD8+ T cells specific for exoerythrocytic-stage Ags, and that activated intrahepatic memory CD8+ T cells are associated with protracted protection. In this study, we further investigated intrahepatic memory CD8+ T cells to elucidate mechanisms required for their maintenance. Using phenotypic markers indicative of activation (CD44, CD45RB), migration (CD62L), and IFN-y production, we identified two subsets of intrahepatic memory CD8+ T cells: the CD44highCD45RBlowCD62LlowCD122low phenotype, representing the dominant effector …


Graduate School Of Computer And Information Sciences Graduate Catalog 2003-2004, Nova Southeastern University Jan 2003

Graduate School Of Computer And Information Sciences Graduate Catalog 2003-2004, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.


Distributed Sensor Network For Civil Infrastructure Health Monitoring, Jose Humberto Mata Hernandez Jan 2003

Distributed Sensor Network For Civil Infrastructure Health Monitoring, Jose Humberto Mata Hernandez

Masters Theses

"This thesis focuses on the development of a robust, low power consumption and cost effective wireless data acquisition, system to be used for civil infrastructure health monitoring. The complete solution that has been developed for this application integrates micro-electromechanical sensing elements (e.g. PVDF sensor); a wireless data acquisition system based on a Bluetooth-enabled radio, a microcontroller with analog to digital conversion capabilities, a power source including a solar cell array for long term operation, and a weatherproof enclosure for on-site installation. The complementary part of the solution is a weatherproof On-site Remote Access Point (ORAP) which collects, stores, and transmits …


Vibration Analysis Via Neural Network Inverse Models To Determine Aircraft Engine Unbalance Condition, Xiao Hu, J. L. Vian, Donald C. Wunsch, J. R. Slepski Jan 2003

Vibration Analysis Via Neural Network Inverse Models To Determine Aircraft Engine Unbalance Condition, Xiao Hu, J. L. Vian, Donald C. Wunsch, J. R. Slepski

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes the use of artificial neural networks (ANNs) with the vibration data from real flight tests for detecting engine health condition - mass imbalance herein. Order-tracking data, calculated from time series is used as the input to the neural networks to determine the amount and location of mass imbalance on aircraft engines. Several neural network methods, including multilayer perceptron (MLP), extended Kalman filter (EKF) and support vector machines (SVMs) are used in the neural network inverse model for the performance comparison. The promising performances are presented at the end.


Jsb Composability And Web Services Interoperability Via Extensible Modeling & Simulation Framework (Xmsf), Model Driven Architecture (Mda), Component Repositories, And Web-Based Visualization, Don Brutzman, Andreas Tolk Jan 2003

Jsb Composability And Web Services Interoperability Via Extensible Modeling & Simulation Framework (Xmsf), Model Driven Architecture (Mda), Component Repositories, And Web-Based Visualization, Don Brutzman, Andreas Tolk

Computational Modeling & Simulation Engineering Faculty Publications

"Study Report prepared for the U. S. Air Force, Joint Synthetic Battlespace Analysis of Technical Approaches (ATA) Studies & Prototyping"

Overview: This paper summarizes research work conducted by organizations concerned with interoperable distributed information technology (IT) applications, in particular the Naval Postgraduate School (NPS) and Old Dominion University (ODU). Although the application focus is distributed modeling & simulation (M&S) the results and findings are in general easily applicable to other distributed concepts as well, in particular the support of operations by M&S applications, such as distributed mission operations. The core idea of this work is to show the necessity of …


Vibration-Based Crack Diagnosis In Rotating Shafts During Acceleration Through Resonance, Jerzy T. Sawicki, Xi Wu, George Y. Baaklini, Andrew L. Gyekenyesi Jan 2003

Vibration-Based Crack Diagnosis In Rotating Shafts During Acceleration Through Resonance, Jerzy T. Sawicki, Xi Wu, George Y. Baaklini, Andrew L. Gyekenyesi

Mechanical Engineering

The dynamic response of a cracked Jeffcott rotor passing through the critical speed with constant acceleration is investigated analytically and numerically. The nonlinear equations of motion are derived and include a simple hinge model for small cracks and Mayes' modified funciton for deep cracks. The equations of motion are integrated in the rotating coordinate system. The angle between the crack centerline and the shaft vibaiton (whirl) vector is used to determine the clsoing and opening of the crack, allowing one to study the dynamic response with and without the rotor weight dominance. Vibration phase response is used as one of …


Application Of Robustness Analysis For Developing A Procedure For Better Urban Transportation Planning Decisions, Deogratias Eustace, Eugene R. Russell, E. Dean Landman Jan 2003

Application Of Robustness Analysis For Developing A Procedure For Better Urban Transportation Planning Decisions, Deogratias Eustace, Eugene R. Russell, E. Dean Landman

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

This paper shows that robustness analysis is a technique with a potential for aiding decision makers in choosing transportation investment projects. In this paper, it has been demonstrated that it can be successfully used in urban transportation planning in conjunction with urban travel demand software. The robustness analysis procedure emphasizes the need, under conditions of uncertainty, to make early decisions in a time-phased sequence, while preserving future options that currently seem attractive. The results of the robustness analysis from the case study used in this paper indicate that the method is simple to understand, easy to use, minimizes future surprises …


The Fate Of Nitrogen In The Marshland Upwelling System, Jeremy Fontenot Jan 2003

The Fate Of Nitrogen In The Marshland Upwelling System, Jeremy Fontenot

LSU Master's Theses

The Marshland Upwelling System (MUS) is an alternative method for coastal dwellers to treat their wastewater. Past studies have dealt with the removal of fecal pathogens from wastewater. However the objectives of this research were to: 1) evaluate the treatment capability of the MUS under high hydraulic loadings and cool temperatures with respect to CBOD5, TKN, TAN, NO2--N, NO3--N, TP, and PO4-P, and 2) determine the ideal flowrate and injection frequency to achieve satisfactory nitrogen removal without hydraulic failure. The artificial wastewater study was performed to evaluate the treatment of …


A Screening Assessment Of Solidification/Stabilization For Storm Water Residuals, Erin Ezell Krielow Jan 2003

A Screening Assessment Of Solidification/Stabilization For Storm Water Residuals, Erin Ezell Krielow

LSU Master's Theses

Metal species infused particulate matter associated with urban rainfall-runoff is a unique and profuse source of pollution. Generated from urban activities, such as traffic activity and vehicular/infrastructure abrasion, contaminated residual material is deposited to roadways during dry weather and transported to surrounding environments and/or best management practice (BMP) treatment facilities during wet-weather events. These particulates range in size from 1 ƒÝm to 10000 ƒÝm and are contaminated with metal species that originate from such sources as vehicular body wear (Cu), tire wear (Zn), and brake dust (Pb). Depending on the efficiencies of the BMP treatment facilities, these containment systems have …


Treatment Of Mixtures Of Methyl Ethyl Ketone (Mek) And Toluene Using Continuous And Sequencing Batch Operated Biofilters, Jorge C. Atoche Jan 2003

Treatment Of Mixtures Of Methyl Ethyl Ketone (Mek) And Toluene Using Continuous And Sequencing Batch Operated Biofilters, Jorge C. Atoche

LSU Master's Theses

During the past decade, biofiltration has increasingly been applied as an air pollution control technology to minimize or eliminate emissions of volatile organic compounds from industrial sources. Although of the ability of this technology to maintain high removal efficiency during relatively steady conditions has been well established for many waste streams, a limitation of this technology has been its inability to maintain high removal efficiency during transient loading conditions typical of industrial operations. In the research described herein, a conventional continuous-flow biofilter (CFB) and a sequencing batch biofilter (SBB) were operated for more than 295 days to treat a model …


Strength Properties Of Granular Materials, Brenda Novoa-Martinez Jan 2003

Strength Properties Of Granular Materials, Brenda Novoa-Martinez

LSU Master's Theses

This thesis presents the results of the experimental work conducted on glass beads in order to investigate the effects of particle size, confining pressure, and surface roughness on the strength properties of the particulate media. Conventional triaxial compression tests were conducted to investigate those effects. Three different sizes of beads were tested: small (diameter = 0.75 – 1.00 mm), medium (diameter = 1.55 – 1.85 mm), and large (diameter = 3.30 – 3.60 mm). The glass beads were subjected to three different confining pressures: 25-, 100-, and 400-kPa. Smooth and etched beads were tested; the etched surface was achieved by …


Heat Transfer In Outdoor Aquaculture Ponds, Jonathan Lamoureux Jan 2003

Heat Transfer In Outdoor Aquaculture Ponds, Jonathan Lamoureux

LSU Master's Theses

An energy balance was developed for heated and unheated earthen aquaculture ponds to 1) determine the relative importance of energy transfer mechanism affecting pond temperature; 2) predict pond temperatures; 3) estimate the energy required to control pond temperatures, and 4) recommend efficient heating and cooling methods. PHATR (Pond Heating and Temperature Regulation), a computer program using 4th order Runge-Kutta numerical method was developed to solve the energy balance using weather, flow rate and pond temperature data. By comparing measured and modeled pond temperatures, the average difference (the average bias) was 0.5°C for unheated ponds and 2.4°C for heated ponds. The …


Mathematical Modeling Analysis Of Floating Bead Biofilter Applications To Domestic Wastewater Treatment, Qiang Wu Jan 2003

Mathematical Modeling Analysis Of Floating Bead Biofilter Applications To Domestic Wastewater Treatment, Qiang Wu

LSU Master's Theses

Floating Bead Biofilters (FBFs) have been applied to aquacultural recirculating tanks and domestic wastewater treatment systems for controlling total ammonia nitrogen (TAN), biochemical oxygen demand (BOD), and total suspended solids (TSS). Support modified media in these FBFs provide a large surface area (1150~1475 m2/m3) so that the active biofilm can be retained in the FBF by attaching to the media surface. Understanding the theories involved in biofilm processes greatly helps in sizing, designing, and modeling of FBF systems. Fundamental biofilm processes like mass transport of various substrates into the biofilm and the substrate utilization within the biofilm were studied. A …


Evaluation Of Static Low Density Media Filters For Use In Domestic Wastewater Treatment, Cynthia Wagener Jan 2003

Evaluation Of Static Low Density Media Filters For Use In Domestic Wastewater Treatment, Cynthia Wagener

LSU Master's Theses

Static Low Density Media (SLDM) filters are submerged granular medium filters that contain a static matrix of floating media. These filters provide concurrent biological and physical treatment, and are therefore classified as bioclarifiers. Through different design and operation strategies, SLDM filters may be used for a variety of functions such as: solid-liquid separation alone, organic conversion and solids capture, nitrification and solids capture, and denitrification and solids capture. For operation as an aerobic unit, an external aeration strategy was developed to preserve the static nature of the bed. In this study, SLDM filters treated a highly variable flow domestic wastewater …


Dechlorination Of 1,2,3,4-Tetrachlorobenzene In Organic Matter- And Mineral-Dominated Soils And Effects Of Typha Latifolia Roots, Lizhu Lin Jan 2003

Dechlorination Of 1,2,3,4-Tetrachlorobenzene In Organic Matter- And Mineral-Dominated Soils And Effects Of Typha Latifolia Roots, Lizhu Lin

LSU Master's Theses

A variety of environments are contaminated with chlorinated benzenes. Therefore, investigating the biodegradation of chlorobenzenes in different types of soils is useful in assessing the feasibility of bioremediation. One mineral-dominated soil: PPI (Petro Processors Inc. site) soil, and three organic matter-dominated soils (natural wetland soil, constructed wetland soil (a mixture of peat, compost and sand), and river sediment) were used to investigate anaerobic biodegradation of 1,2,3,4-Tetrachlorobenzene (1,2,3,4-TeCB) using laboratory microcosms. To determine whether methanogens were directly responsible for dechlorination, a comparative study using 2-bromoethanesulfonic acid (BES) for inhibition of methanogenesis was conducted. Hydrogen and methane concentrations, and microbial diversities were …


Identity Management, Duncan A. Buell, Ravi Sandhu Jan 2003

Identity Management, Duncan A. Buell, Ravi Sandhu

Faculty Publications

No abstract provided.


Rainfall-Runoff Control: Variably Saturated Transport For An Infiltration System Controlling Water Quality And Quantity, Zheng Teng Jan 2003

Rainfall-Runoff Control: Variably Saturated Transport For An Infiltration System Controlling Water Quality And Quantity, Zheng Teng

LSU Doctoral Dissertations

Rainfall-runoff impacted by anthropogenic activities transports significant quantities of particulate, aqueous and complexed constituents. These diffuse, unsteady and stochastic event-based loadings are unique challenges for water quality and quantity control. The design, water quality and quantity functions of a partial exfiltration reactor (PER) utilizing Fe-coated-sand and porous pavement (CPP) is examined specifically across three representative rainfall-runoff events. Total concentrations and mass for metals (Zn, Pb, Cu and Cd), suspended solids, and Chemical oxygen demand were reduced significantly. Rainfall-runoff volume and peak flow were reduced and time to peak was extended. Influent dm/dp ratios based on particle analyses suggest that the …


Biomechanical Effects Of Cyclic Loading On The Lower Back, Lakiesha Claude Jan 2003

Biomechanical Effects Of Cyclic Loading On The Lower Back, Lakiesha Claude

LSU Master's Theses

More than 30 million people in the United States may have low back pain at any time, and 10 million of them have chronic symptoms. Epidemiological studies indicate that along with axial compressive loads, other factors including repetitive twisting or lateral bending and lifting are significant risk factors for low-back disorders. Literature repeatedly confirms that cyclic occupational functions expose workers to a 10-fold increase in episodes of low back injury and pain. This study examined the biomechanical effects of cyclical loading on the lower back. Twenty in vivo feline preparations were subjected to passive cyclic loading at 20 N (n=6), …


Rotary Kiln Incineration Of Hazardous Wastes: Pilot-Scale Studies At Louisiana State University, John Sutherland Earle Jan 2003

Rotary Kiln Incineration Of Hazardous Wastes: Pilot-Scale Studies At Louisiana State University, John Sutherland Earle

LSU Doctoral Dissertations

Studies of incineration of surrogates for hazardous wastes are conducted in the pilot-scale rotary kiln incinerator (RKI) at Louisiana State University (LSU) in Baton Rouge, Louisiana. The purpose of the research is to investigate methods of treating and destroying hazardous wastes in a cost-effective and environmentally sound way. The objective is to provide process data that will contribute to increased knowledge for RKI design and operation. The LSU facility is a College of Engineering Combustion Laboratory that is unique in its large size as a university laboratory. It is equipped with individual instruments for analysis of O2, CO, …


A Novel Hydrogen And Oxygen Generation System, Zhiyong Peng Jan 2003

A Novel Hydrogen And Oxygen Generation System, Zhiyong Peng

LSU Master's Theses

This study examined the three phases of the sorption-enhanced SMR process for H2 production: production of low-CO hydrogen using the standard Ni-based reforming catalyst and high purity CaO sorbent precursor, evaluation of combined reforming catalyst-sorbent samples supplied by TDA, and an Aspen simulation study of the process for simultaneous production of H2 and O2. The production of low-CO (<20ppmv) hydrogen was studied using the single-step sorption-enhanced steam methane reforming process. The effects of temperature, volumetric feed rate, and feed gas composition on the purity of H2 and the content of CO were investigated. The feasibility of producing 95+% H2 with CO content of less than 20ppmv was experimentally proven in a test at 480¡ãC and 5 atm using a commercial Ni-based catalyst and the calcium-based CO2 sorbent. The feed gas contained 20% CH4 and 80% H2O, while the product gas contained 97.8% H2 and 17 ppmv CO. With this low CO concentration, the product can be used in a proton exchange membrane (PEM) fuel cell without further purification. The catalyst-sorbent samples from TDA Research Inc. were extensively studied and evaluated with respect to their performance in the steam-reforming reaction using both the fixed-bed reactor system and TGA. The activity of the catalyst samples having different compositions was examined and compared at different temperatures and space velocities using a feed gas containing 11.1% CH4 with a steam-to-carbon (S/C) ratio of 3.0. The sorption activity and durability was also examined in the TGA system. The overall hydrogen and oxygen co-production process was studied and evaluated using the Aspen Plus simulator. Material and energy balance calculations showed that this system can produce 99+% purity hydrogen and oxygen simultaneously with efficient energy integration. This process is balanced on power consumption and generation, so no external power is required.


The Determination Of Appropriate Phosphogypsum: Class C Fly Ash : Portland Type Ii Cement Compositions For Use In Marine Applications, Pradyot Sudhakar Deshpande Jan 2003

The Determination Of Appropriate Phosphogypsum: Class C Fly Ash : Portland Type Ii Cement Compositions For Use In Marine Applications, Pradyot Sudhakar Deshpande

LSU Master's Theses

Phosphogypsum (PG, CaSO4·2H2O) is a waste by-product produced during the wet manufacturing phosphoric acid process. Phosphoric acid is manufactured by processing phosphate rock that contains relatively high concentrations of naturally occurring radioactive impurities which makes PG a radioactive material. PG also contains certain trace metals including As, Ba, Cd, Cr and Pb and radioactive contaminants such as Radium226 and Uranium238 that pose potential hazard to human health and the environment. According to USEPA, the current allowable disposal method for PG is stack piling. This research was focused on stabilizing PG with Portland Type II …