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Methane Consumption In Temperate And Subarctic Forest Soils: Rates, Vertical Zonation, And Responses To Water And Nitrogen, A. P.S. Adamsen, G. M. King Jan 1993

Methane Consumption In Temperate And Subarctic Forest Soils: Rates, Vertical Zonation, And Responses To Water And Nitrogen, A. P.S. Adamsen, G. M. King

Faculty Publications

Rates of methane consumption were measured in subarctic coniferous and temperate mixed-hardwood forest soils, using static chambers and intact soil cores. Rates at both sites were generally between 1 and 3 mg of CH4 m-2 day-1 and decreased with increasing soil water contents above 20%. Addition of ammonium (1 μmol g of soil-1) strongly inhibited methane oxidation in the subarctic soils; a lesser inhibition was observed for temperate forest samples. The response to nitrogen additions occurred within a few hours and was probably due to physiological changes in the active methane-consuming populations. Methane consumption in soils from both sites was …

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Solid-State Deuterium Nmr Spectroscopy Of D5-Phenol In White Portland Cement: A New Method For Assessing Solidification/Stabilization, Michael A. Janusa, Xiao Wu, Frank K. Cartledge, Leslie G. Butler Jan 1993

Solid-State Deuterium Nmr Spectroscopy Of D5-Phenol In White Portland Cement: A New Method For Assessing Solidification/Stabilization, Michael A. Janusa, Xiao Wu, Frank K. Cartledge, Leslie G. Butler

Faculty Publications

We have developed a new NMR-based procedure for studying waste/cement interactions. This is the first use of deuterium NMR spectroscopy to study waste solidification/stabilization (S/S). The main feature of deuterium NMR spectroscopy is the ability to monitor molecular reorientations over a wide range of reorientation rates. This technique allows one to determine if a particular deuterated organic waste is effectively solidified/stabilized and to determine the lower limit of the bond strength between the waste and the cement matrix. Comparison of the predicted and experimental deuterium NMR spectra show that phenol is mainly dissolved in pore waters and, thus, poorly immobilized …

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Results From The Soviet-American Gallium Experiment, O. L. Anosov, E. L. Faizov, V. N. Gavrin, A. V. Kalikhov, T. V. Knodel, I. I. Knyshenko, V. N. Kornoukhov, I. N. Mirmov, A. V. Ostrinsky, A. M. Pshukov, A. A. Shikhin, P. V. Timofeyev, E. P. Veretenkin, V. M. Vermul, G. T. Zatsepin, T. J. Bowles, S. R. Elliott, J. S. Nico, H. A. O'Brien, D. L. Wark, J. F. Wilkerson, B. T. Cleveland, R. Davis, K. Lande, M. L. Cherry, R. T. Kouzes Jan 1993

Results From The Soviet-American Gallium Experiment, O. L. Anosov, E. L. Faizov, V. N. Gavrin, A. V. Kalikhov, T. V. Knodel, I. I. Knyshenko, V. N. Kornoukhov, I. N. Mirmov, A. V. Ostrinsky, A. M. Pshukov, A. A. Shikhin, P. V. Timofeyev, E. P. Veretenkin, V. M. Vermul, G. T. Zatsepin, T. J. Bowles, S. R. Elliott, J. S. Nico, H. A. O'Brien, D. L. Wark, J. F. Wilkerson, B. T. Cleveland, R. Davis, K. Lande, M. L. Cherry, R. T. Kouzes

Faculty Publications

A radiochemical 71Ga-71Ge experiment to determine the primary flux of neutrinos from the Sun began measurements of the solar neutrino flux at the Baksan Neutrino Observatory in 1990. The number of 71Ge atoms extracted from 30 tons of gallium in 1990 and 57 tons in 1991 was measured in twelve runs during the period of January 1990 to December 1991. For the 1990 data, we observed the capture rate to be 20 + 15 -20 (stat) ± 32 (syst) SNU, resulting in a limit of less than 79 SNU (90% CL). This is to be compared with 132 SNU predicted …

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Louisiana Agriculture Magazine, Winter 1993, Lsu Agricultural Experiment Station Jan 1993

Louisiana Agriculture Magazine, Winter 1993, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Mechanisms Of Crater Formation While Drilling A Well., Luiz Alberto Santos Rocha Jan 1993

Mechanisms Of Crater Formation While Drilling A Well., Luiz Alberto Santos Rocha

LSU Historical Dissertations and Theses

Current well control practice for land or bottom-supported marine rigs usually calls for shutting-in the well when a kick is detected if sufficient casing has been set to keep any flow underground. In addition, the working pressure of the casing and surface equipment is maintained high enough to insure that formation fracture occurs before a failure of these items. Even if high shut-in pressures are seen, an underground blowout is preferred over a surface blowout. On the other hand, an operator will put the well on a diverter if he believes that the casing is not set deep enough to …

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Field Evaluation Of The Movement Of Agricultural Chemical Contaminants In Alluvial Soils With A Shallow Water Table., Orlino Agustin Mercado Jan 1993

Field Evaluation Of The Movement Of Agricultural Chemical Contaminants In Alluvial Soils With A Shallow Water Table., Orlino Agustin Mercado

LSU Historical Dissertations and Theses

The movement of agricultural chemical contaminants in alluvial soils with a shallow water table in a warm, humid environment was evaluated in this study. Bromide, a non-adsorbent tracer, was used to assess the pathways of water and solute in the soil profile. The movement and fate of three commonly used herbicides: Trifluralin, Metolachlor, and Metribuzin were determined. The data gathered from the herbicide study were used to compare with the results of simulation to validate the pesticide component of the GLEAMS model. The study was conducted at the Ben Hur Research Farm of the Louisiana Agricultural Experiment Station. Five relatively …

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A Non-Proportional Cyclic Plasticity Model For Metals With Ratchetting Effects., Srinivasan Madras Sivakumar Jan 1993

A Non-Proportional Cyclic Plasticity Model For Metals With Ratchetting Effects., Srinivasan Madras Sivakumar

LSU Historical Dissertations and Theses

The path-dependent and nonlinear behavior of metallic materials subjected to cyclic loading is modelled using the proposed hardening rule. It uses mainly two surfaces, a yield and a limit surface and includes the memory effects through a separate surface called the memory surface which is obtained from a maximum stress criterion. The model considers the facts that the motion of the center of the yield surface in the stress space is mainly governed by the direction of the deviatoric stress rate and that the uniqueness of the solution requires nesting of the two surfaces. The model proposed satisfies both conditions …

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A Cross-Age Study Of Students' Knowledge Of Insect Metamorphosis: Insights Into Their Understanding Of Evolution., Mary Susan Nichols Jan 1993

A Cross-Age Study Of Students' Knowledge Of Insect Metamorphosis: Insights Into Their Understanding Of Evolution., Mary Susan Nichols

LSU Historical Dissertations and Theses

Insect metamorphosis is relatively easy to explain at a superficial level, but a deep understanding of the concept reveals a complex array of interrelationships, most importantly those that address evolution. This is significant because, in biology, evolution is considered to be a central theme. Participants for this study were selected from grades 5, 7, 9, and 11 according to low, middle, or high achievement levels in their science classes, and to scores on a national achievement test. The research incorporated a three-level response strategy in order to ascertain more completely students' knowledge of insect metamorphosis, and to better suggest how …

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Worksite Health Promotion In America: The Impact Of Organizational Context On Corporate Wellness Programming., Neller Ree Simpkins Jan 1993

Worksite Health Promotion In America: The Impact Of Organizational Context On Corporate Wellness Programming., Neller Ree Simpkins

LSU Historical Dissertations and Theses

The purpose of this study is to examine the factors associated with corporate wellness programming in contemporary U.S. business organizations. First, I construct an ideal-type of wellness program components in order to profile varying arrays (i.e., number and types) of health and fitness activities across corporations. Then, I detail the extent of health promotion programming in business organizations and in major corporations, using the National Survey of Worksite Health Promotion Activities and the Worksite Health Promotion Program Survey of Fortune 500 companies. The central research task of this study is to explore the factors that account for the diversity observed …

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Dynamic Behavior Of Headspace Gases In Modified Atmosphere Packaging For Meat., Yanyun Zhao Jan 1993

Dynamic Behavior Of Headspace Gases In Modified Atmosphere Packaging For Meat., Yanyun Zhao

LSU Historical Dissertations and Theses

Headspace gas composition in food packaging undergoes dynamic changes as a result of film permeability, postmortem metabolic activity, CO$\sb2$ absorption in water and lipid, and bacteria growth and respiration. A methodology to study dynamic behavior of headspace CO$\sb2$ was developed and used to identify the significant factors influencing CO$\sb2$ behavior within modified atmosphere packaging (MAP) systems for beef. Additionally, a mathematical structure suitable for modeling microbial growth in MAP systems was presented. A combined analytical and experimental method was developed to investigate headspace CO$\sb2$ changes during isothermal storage. The ideal gas law was used as a theoretical basis, and a …

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African American Students' Perception Of Mandatory Participation In A Remedial Program At An Historically Black University In The South., Deborah Burson Smith Jan 1993

African American Students' Perception Of Mandatory Participation In A Remedial Program At An Historically Black University In The South., Deborah Burson Smith

LSU Historical Dissertations and Theses

Academically underprepared college bound students and remedial instruction at the collegiate level continue to be serious and recurring problems for postsecondary institutions throughout the United States. Although many institutions have attempted to address the academic needs of underprepared students by providing mandatory programs with varied approaches in reading, writing, and mathematics, educators, theorists, and scholars have given little attention to the effects of mandatory participation on students' perceptions of a remedial program or classroom. This research is designed to provide an inside view of the remedial classroom and underprepared African American students' interpretations of certain practices that may impact their …

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Reconstructability Theory For General Systems And Its Application To Automated Rule Learning., Sudhir Kumar Trivedi Jan 1993

Reconstructability Theory For General Systems And Its Application To Automated Rule Learning., Sudhir Kumar Trivedi

LSU Historical Dissertations and Theses

The two problems in reconstructability analysis, abbreviated as RA, are referred to as the reconstructability problem and the identification problem. The former relates to the process of reconstructing a given system under a given criterion from the knowledge of its subsystems and, during this process, identifying those subsystems that are important in the reconstruction. The latter allows the identification of an unknown system from the knowledge of its subsystems. The advent of RA has intensified the research efforts on system studies. The objective of this research is to study the process of system reconstruction for general systems and apply it …

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A Policy Approach To Educational Leadership In The State Legislature., Sue Wells Weaver Jan 1993

A Policy Approach To Educational Leadership In The State Legislature., Sue Wells Weaver

LSU Historical Dissertations and Theses

This study investigated legislative expert influence in the context of educational policy decisions. Institutional and behavioral approaches to legislative study were compared. In a chi square analysis of all legislative education enrollments in the 1993 Regular Session of the Louisiana Legislature, legislation introduction success was positively associated with author's level of credential and reputation expertise. Relative importance of type of expertise was indeterminable and some influence was unaccountable in the analysis. The policy approach, based on Theodore Lowi's theory that policy predicts politics, integrated the prior approaches. Lowi's distributive-regulatory-redistributive schema informed the independent policy variables, while influence, role, and subsystem …

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The Significance Of Beta-72 Asparagine Methylation In C-Phycocyanin., Beth Ann Thomas Jan 1993

The Significance Of Beta-72 Asparagine Methylation In C-Phycocyanin., Beth Ann Thomas

LSU Historical Dissertations and Theses

A novel post-translationally modified asparagine, $\gamma$-N-methylasparagine (NMA), has been characterized at the $\beta$-72 site in many phycobiliproteins. The behavior of a NMA-containing peptide under Edman degradation conditions employed for sequence analysis was examined; NMA can be reproducibly identified in protein sequences by careful attention to repetitive yields and the presence of minor peaks. The effects of asparagine methylation on photosynthetic rates in the cyanobacterium Synechococcus PCC 7942 and two methylase-minus mutants was measured by steady-state oxygen evolution in whole cells. The methylase-minus mutants demonstrated lower rates of electron transfer through Photosystem II under conditions in which phycobilisomes were preferentially illuminated …

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Effect Of Cementation On Cone Resistance In Sands: A Calibration Chamber Study., Anand Jagadeesh Puppala Jan 1993

Effect Of Cementation On Cone Resistance In Sands: A Calibration Chamber Study., Anand Jagadeesh Puppala

LSU Historical Dissertations and Theses

An understanding of the effect of cementation on geotechnical properties of soil deposits is gaining increasing attention in the profession. When low levels of cementation in sands are neglected, pile capacity and slope stability are underestimated and liquefaction is overestimated. It is essential to devise schemes to identify cementation in soil investigations and develop methods in evaluating engineering characteristics of cemented deposits. The objective of this study is to develop a method to identify cementation in sands and assess the engineering characteristics of cemented sand deposits using the cone penetration testing scheme. The scope of the study includes evaluation of …

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Stress-Strain Analysis Of Adhesive-Bonded Composite Single-Lap Joints Under Various Loadings., Chihdar Yang Jan 1993

Stress-Strain Analysis Of Adhesive-Bonded Composite Single-Lap Joints Under Various Loadings., Chihdar Yang

LSU Historical Dissertations and Theses

The objective of this study is to develop mathematical relations for stress and strain distributions of adhesive-bonded single-lap joints under cylindrical bending and tension. Based on the Theory of Mechanics of Composite Materials and Anisotropic Laminated Plate Theory, elastic models are proposed to predict the stress-strain distributions of the laminates and the adhesive under cylindrical bending and tension. A simplified elastic-plastic model is also recommended for the case of tension loading. For each case, the Laminated Anisotropic Plate Theory is first used in the derivation of the governing equations of the two bonded laminates. The entire coupled system is then …

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Chemical Vapor Deposition To Titanium Dioxide Thin Films., Qingming Zhang Jan 1993

Chemical Vapor Deposition To Titanium Dioxide Thin Films., Qingming Zhang

LSU Historical Dissertations and Theses

TiO$\sb2$ thin films have been prepared by the thermal decomposition of titanium tetra-isopropoxide (TTIP) in two low pressure chemical vapor deposition (LPCVD) reactors. The two reactors are the vertical tube hot-wall reactor and the stagnation point flow single-wafer cold-wall reactor. The effects of TTIP partial pressure, substrate temperature, gas flow rate, and reactor pressure on the growth rate of TiO$\sb2$ film were examined. Aerosol formation, wall effects, the effect of water content, and the effect of reactor geometry were also investigated. The experiments were performed in the substrate temperature range 225-400$\sp\circ$C, inlet TTIP partial pressure range $6.4\times10\sp{-4}$ $-$ 0.4 torr, …

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A Framework For Assessing Consumer Satisfaction With Credence-Based Services: A Cognitive Script Approach., Bruce L. Alford Jan 1993

A Framework For Assessing Consumer Satisfaction With Credence-Based Services: A Cognitive Script Approach., Bruce L. Alford

LSU Historical Dissertations and Theses

Service marketers have long needed research developed within the services area for services application. The majority of satisfaction research has pertained to products and attributes contained by those products. Yet with the acknowledged differences between services and products, there is still a void in the services satisfaction literature. The research attempted to develop a service-based model of consumer satisfaction with credence-based services, using cognitive scripts for the formation of expectations. Scripts represent a cognitive movie of what events should happen and in what order. When this expected process of events is deviated by the service provider, correspondent inference was posited …

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An Algorithm For Supervisory Multivariable Constrained Optimization Of Industrial Processes., William E. Daniel Jr Jan 1993

An Algorithm For Supervisory Multivariable Constrained Optimization Of Industrial Processes., William E. Daniel Jr

LSU Historical Dissertations and Theses

An algorithm is presented for supervisory optimization of industrial processes that combines the minimization of operating costs with process operating constraints. The supervisory algorithm manipulates the set points of a lower-level control system and the set points are updated at long enough intervals of time so that the process reaches steady state between set point updates. This steady state assumption greatly simplifies the algorithm computations and, more importantly, significantly reduces the effort required for process identification. This dissertation develops the algorithm and then presents results from its application to a simulated distillation train and reactor feed network. In both applications, …

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Forecasting The Economic Effects Of Produced Waters Discharge Regulations On Oil And Gas Activity In Coastal Louisiana., Allen Paul Dupont Jan 1993

Forecasting The Economic Effects Of Produced Waters Discharge Regulations On Oil And Gas Activity In Coastal Louisiana., Allen Paul Dupont

LSU Historical Dissertations and Theses

Proposed regulations would restrict surface disposal of untreated produced waters by oil and gas producers in coastal south Louisiana. The regulations would impose costs on oil and gas activity. This dissertation develops an integrated model of exploration and production activities which utilizes both economic and geological concepts, in which the cost of compliance with the proposed regulations is treated as a reduction in the real net price of oil. The goal is to predict the effects of the proposed regulations on exploration and production activity in the study region. The main findings are: (i) the proposed regulations would reinforce the …

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Structural Analysis And Methionine Ehancement Of The Bean Seed Storage Protein Phaseolin., John M. Dyer Jan 1993

Structural Analysis And Methionine Ehancement Of The Bean Seed Storage Protein Phaseolin., John M. Dyer

LSU Historical Dissertations and Theses

Common beans are widely utilized as a food source, yet are limited as a complete source of protein due to low levels of methionine, an essential amino acid for humans. A protein engineering strategy was developed to increase the methionine content of phaseolin, the primary seed storage protein in common beans. The engineering strategy consists of three major parts. In the first part, a set of biophysical probes was developed to characterize the stability of wild-type and modified phaseolin proteins. I used absorbance, fluorescence emission, circular dichroism, and fluorescence polarization anisotropy to monitor phaseolin denaturation induced by urea, guanidinium chloride, …

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Synthesis And Characterization Of Copolycarbonates Derived From 2,2,4,4-Tetramethyl-1,3-Cyclobutanediol., Carey Cecil Geiger Jan 1993

Synthesis And Characterization Of Copolycarbonates Derived From 2,2,4,4-Tetramethyl-1,3-Cyclobutanediol., Carey Cecil Geiger

LSU Historical Dissertations and Theses

Alternating copoly(bis-phenol-co-2,2,4,4-tetramethyl-1,3-cyclobutane) carbonates are synthesized from 2,2,4,4-tetramethyl-1,3-cyclobutanedichloro-formate and the corresponding bis-phenol using a solution polymerization technique. The bis-phenols consist of various 4,4$\sp\prime$-substituted diphenols including: 2,2-propane; 1,1-cyclohexane; 1,1-(4-t-butyl)cyclohexane; 2,2-tricyclo (3.3.1.1) decane; 2,2-bicyclo (3.2.1) heptane; 1,1-(1-phenyl)ethane; 2,2-hexafluoropropane; carbonyl; 9,9-fluorene; sulfide; sulfone; and diphenyl-methane. Crystal structures of the 9,9-tricyclo (3.3.1.1$\sp{3,7}$) decane and 1,1-(4-t-butyl)cyclohexane bis-phenols, previously unreported in the literature, confirm the structures proposed and reveal that the compounds are solvated with acetonitrile and toluene, respectively. The copolymers are isolated by precipitation in methanol; yields ranging from 50 to 80% are obtained. All monomers and polymers reported are characterized by $\sp1$H and $\sp{13}$C NMR …

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Voices From Home: Familial Bonds In The Works Of Horton Foote (1916- )., Marion Dean Castleberry Jan 1993

Voices From Home: Familial Bonds In The Works Of Horton Foote (1916- )., Marion Dean Castleberry

LSU Historical Dissertations and Theses

For more than half a century Horton Foote has been regarded as one of America's foremost dramatists. Born and reared in Wharton, Texas, he wrote his first play Wharton Dance in 1939, at the age of twenty-three, and gained his first Broadway production, Only The Heart, in 1944. His success as a playwright led to television, for which he wrote some of his finest dramas, and finally to a distinguished career in film. Foote has received numerous awards for his plays and screenplays, including Academy Awards for To Kill A Mockingbird (1962) and Tender Mercies (1983) and an Academy Award …

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The Distribution Of Toxic Sources In Louisiana: An Analysis Of Community Socioeconomic Characteristics And Industry Behavior., Salpie Sarkis Djoundourian Jan 1993

The Distribution Of Toxic Sources In Louisiana: An Analysis Of Community Socioeconomic Characteristics And Industry Behavior., Salpie Sarkis Djoundourian

LSU Historical Dissertations and Theses

The distribution patterns of toxic sources in Louisiana reveal that some communities may be disproportionately exposed to potential environmental risks. This dissertation examines whether the location and environmental control behavior of toxic polluters are systematically related to the socioeconomic and racial characteristics of communities. The study identifies who lives in the immediate proximity of toxic sources and determines whether the characteristics of these communities are different from those of Louisiana's general population. The results reveal that income levels in communities that host toxic sources are consistently and significantly lower than the state averages. A distance gradient analysis indicates that as …

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A Study Of Heat Transfer In Rotary Desorbers Used To Remediate Contaminated Soils., Charles Alan Cook Jan 1993

A Study Of Heat Transfer In Rotary Desorbers Used To Remediate Contaminated Soils., Charles Alan Cook

LSU Historical Dissertations and Theses

A comprehensive heat transfer model is developed which describes heat transfer phenomena in rotary desorbers. This model predicts the temperatures of the solids bed and gases in the desorber and the rate of water evaporation from the solids. Emphasis is placed on describing the heat transfer process between the rotating wall of a desorber and the adjacent bed of solids. A heat-balance integral method is used to model heat conduction from the wall to adjacent wet bed particles. This solution includes the effects of water evaporation near the wall and a thermal contact resistance between the wall and the first …

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Hydrologic Modelling With A Spatial Database., Richard Gilbert Greene Jan 1993

Hydrologic Modelling With A Spatial Database., Richard Gilbert Greene

LSU Historical Dissertations and Theses

Hydrologic modelling can be enhanced and improved through the utilization of a Geographic Information System (GIS). Information can be stored and analyzed by the tools available within a GIS to create a spatial database that realistically represents a watershed for hydrologic modelling. This study presents an approach whereby the data available in the GIS determine the modelling strategy. The soil, topography and land cover data for the watershed were analyzed with the spatial analysis tools of a GIS to determine the hydrologic response areas. The coordinate values that define the locations and boundaries of features in the GIS were used …

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Object-Oriented Modeling And Design Using Delta, An Incremental Design Language., Nancy Kay Gautier Jan 1993

Object-Oriented Modeling And Design Using Delta, An Incremental Design Language., Nancy Kay Gautier

LSU Historical Dissertations and Theses

Object-oriented technology has opened the doors for many new ideas in system development. The object-oriented paradigm has produced many new object-oriented programming languages. As with any new methodology, a need for formalism arises to remove ambiguities and inconsistencies and to bring a sense of continuity to software design. Formal languages provide a sound basis for software development throughout the software life cycle. This work presents a set of characteristic features for object-oriented design languages and defines a formal object-oriented design language, DELTA. The rapidly changing face of software has led to an ever increasing need to update out-of-date methods and …

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Mathematical Model Of Hairy Root Growth., Seungdo Kim Jan 1993

Mathematical Model Of Hairy Root Growth., Seungdo Kim

LSU Historical Dissertations and Theses

Hairy roots produce secondary metabolites which have been used as specialty chemicals. The mathematical models of hairy root growth kinetics can guide the design and scale-up of root cultures. An unstructured segregated and a chemically structured segregated models for hairy growth kinetics are formulated with rules of root branching processes. The deterministic branching rule and the stochastic branching rule are studied. For the deterministic rule where two branching parameters are assumed constant, the number of tips can be obtained by solving a linear difference equation. The conceptual framework established for the deterministic rule is used to formulate a stochastic rule …

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Pollutant Transport In Buoyancy Driven Atmospheric Flows., Youn-Seo Koo Jan 1993

Pollutant Transport In Buoyancy Driven Atmospheric Flows., Youn-Seo Koo

LSU Historical Dissertations and Theses

Due to the complexity of some buoyancy driven atmospheric flows, it is sometimes not possible to accurately predict pollutant transport on the basis of sparse wind field measurements. A possible solution is mathematical modelling of both the flow and pollutant transport. In order to overcome shortcomings of the conventional E-$\epsilon$ model such as defining proportionality coefficients (c$\sb{\rm m},$ c$\sb{\rm h})$ and to develop a more general model of stratified environmental flows, a modified E-$\epsilon$ model was proposed through use of the algebraic stress model including wall proximity effects. The resulting model was compared herein to data and higher order simulations …

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Mobilization Of A Hydrophobic Organic Compound Using Surfactant For Soil Washing., Minwen Liu Jan 1993

Mobilization Of A Hydrophobic Organic Compound Using Surfactant For Soil Washing., Minwen Liu

LSU Historical Dissertations and Theses

Soil washing using surfactants is a promising alternative for the conventional pump-and-treat method of removing hydrophobic organic compounds. The interactions and the transport of the chemicals have been studied by batch and column experiments. Sodium dodecylsulfate (SDS), an anionic surfactant, and anthracene, a hydrophobic organic, were chosen as the representative surfactant and contaminant, respectively. Fine sand and native soil were used as formation media. The experimental results indicated that the maximum loss of SDS on native soil from the solution was observed when the aqueous SDS concentration was in the region of the critical micelle concentration, and this loss was …

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