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Responses Of Methanotrophic Activity In Soils And Cultures To Water Stress, S. Schnell, G. M. King Jan 1996

Responses Of Methanotrophic Activity In Soils And Cultures To Water Stress, S. Schnell, G. M. King

Faculty Publications

Diffusive gas transport at high water contents and physiological water stress at low water contents limited atmospheric methane consumption rates during experimental manipulations of soil water content and water potential. Maximum rates of atmospheric methane consumption occurred at a soil water content of 25% (grams per gram [dry weight]) and a water potential of about - 0.2 MPa. In contrast, uptake rates were highest at a water content of 38% and a water potential of -0.03 MPa when methane was initially present at 200 ppm. Uptake rates of atmospheric and elevated methane decreased when water potentials were reduced by adding …

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Regulation Of Methane Oxidation In A Freshwater Wetland By Water Table Changes And Anoxia, Peter Roslev, Gary M. King Jan 1996

Regulation Of Methane Oxidation In A Freshwater Wetland By Water Table Changes And Anoxia, Peter Roslev, Gary M. King

Faculty Publications

The effects of water table fluctuations and anoxia on methane emission and methane oxidation were studied in a freshwater marsh. Seasonal aerobic methane oxidation rates varied between 15% and 76% of the potential diffusive methane flux (diffusive flux in the absence of aerobic oxidation). On an annual basis, approximately 43% of the methane diffusing into the oxic zone was oxidized before reaching the atmosphere. The highest methane oxidation was observed when the water table was below the peat surface. This was confirmed in laboratory experiments where short-term decreases in water table levels increased methane oxidation but also net methane emission. …

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Nutritional Status In Rural Nigerians [17], R. Cooper, C. Rotimi, J. Kaufman, A. Luke Jan 1996

Nutritional Status In Rural Nigerians [17], R. Cooper, C. Rotimi, J. Kaufman, A. Luke

Faculty Publications

No abstract provided.

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Louisiana Agriculture Magazine, Winter 1996, Lsu Agricultural Experiment Station Jan 1996

Louisiana Agriculture Magazine, Winter 1996, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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How To (Mis)Read Hogarth Or, Ekphrasis Galore, Peter Wagner Jan 1996

How To (Mis)Read Hogarth Or, Ekphrasis Galore, Peter Wagner

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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The Star Wars Trilogy: Mythology And Modernity, Jeffrey P. Dupuis Jan 1996

The Star Wars Trilogy: Mythology And Modernity, Jeffrey P. Dupuis

Honors Capstones

No abstract provided.

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Longitudinal Dispersion And Interstitial Velocity Relationship In Subsurface Flow Constructed Wetlands., Gianna M. Cothren Jan 1996

Longitudinal Dispersion And Interstitial Velocity Relationship In Subsurface Flow Constructed Wetlands., Gianna M. Cothren

LSU Historical Dissertations and Theses

Treatment of municipal and rural wastewater using subsurface flow constructed wetlands (SFCW's) is growing in popularity. These systems often consist of an excavated cell containing 2-3 in. rock with the wastewater level maintained below the media surface. A SFCW is a natural form of wastewater treatment which removes organics and nutrients based on the attached growth of microorganisms on crushed rocks where biological reactions take place. The currently accepted design procedure is based on the first order plug flow model, although tracer studies have shown that flow conditions are not well represented by the plug flow condition. This design rationale …

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Effects Of Organic Waste Amendments, Herbicides, And Weed Hosts On Pythium Root Rot Of Sugarcane., Nimal Mudiyans Dissanayake Jan 1996

Effects Of Organic Waste Amendments, Herbicides, And Weed Hosts On Pythium Root Rot Of Sugarcane., Nimal Mudiyans Dissanayake

LSU Historical Dissertations and Theses

Three objectives that could lead to improved understanding and management of Pythium root rot of sugarcane were addressed. First, the potential of amending soil with different organic wastes to suppress root rot was evaluated, and the biological and chemical properties of wastes that may contribute to disease suppression were identified. Secondly, herbicide interactions with root rot affecting sugarcane growth were assessed. Finally, the role of weeds in disease epidemiology was investigated. Greenhouse and laboratory studies indicated soil amendment with some organic wastes offers a sustainable disease management option through biological control. Amendment with different wastes had variable effects. Sewage sludge, …

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Magneto-Optical Properties Of Cubic Ferromagnetic Metals., Neeraj Arvind Mainkar Jan 1996

Magneto-Optical Properties Of Cubic Ferromagnetic Metals., Neeraj Arvind Mainkar

LSU Historical Dissertations and Theses

I present a first principles, all electron, linear combination of Gaussian orbitals calculation of a comprehensive collection of magneto-optical properties of the cubic ferromagnetic metals nickel, iron and cobalt based on density functional theory. Among the many magneto-optical effects, this is the first ab initio study of the equatorial Kerr effect for absorption in the optical as well as the X-ray region, where it is called the X-ray magnetic linear dichroism. I find that in the optical region, this effect is of the order of 2% while in the X-ray region, it is of the order of 1% for the …

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Composted Municipal Waste And Fertilizer Effects On Soils And Sugarcane., Xianliang Wan Jan 1996

Composted Municipal Waste And Fertilizer Effects On Soils And Sugarcane., Xianliang Wan

LSU Historical Dissertations and Theses

Application of composted municipal waste to agricultural lands has potential benefits to improve soil fertility and crop yield. It may lead to accumulation of heavy metals within soils and leaching of nutrients and heavy metals into the ground water. The objectives of this study were to investigate: (1) the effects of composted municipal waste and fertilizer on soil chemical properties and sugarcane elemental uptake and yield; and (2) the leachability of elements in compost amended soils. Results of three field experiments from a Baldwin silty clay loam and a Memphis silt loam showed that compost application at $\ge$33.6 Mg/ha increased …

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Interaction Between Ap-1 Proteins And Glucocorticoid Receptors In Regulation Of Lymphokine Activated Killer (Lak) Cell Activity In The Equine Species., Jing Bu Jan 1996

Interaction Between Ap-1 Proteins And Glucocorticoid Receptors In Regulation Of Lymphokine Activated Killer (Lak) Cell Activity In The Equine Species., Jing Bu

LSU Historical Dissertations and Theses

This project was performed in order to determine whether exercise-induced increases in plasma cortisol concentrations may be responsible for enhanced lymphokine activated killer (LAK) cell activity. Secondly, this project included preliminary experments which were designed to test the hypothesis that stimulatory effects of cortisol on LAK cell activity may be due to cross-talk between signalling systems important to glucocorticoid effects and stimuli which act through nuclear activator protein-1 (AP-1). Blood samples were collected from resting horses in order to determine whether the animals had normal plasma glucocorticoid concentrations. All horses included in these experiments had $10\sp{-7}$ to $10\sp{-8}$M cortisol concentrations …

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Social Tolerance For Drug Use Among Junior High School Students In Taipei, Taiwan., San-Yi Li Jan 1996

Social Tolerance For Drug Use Among Junior High School Students In Taipei, Taiwan., San-Yi Li

LSU Historical Dissertations and Theses

This study examines the degree of social tolerance for drug use among junior high school students in Taipei, Taiwan, and the relationships between their social tolerance for drug use and their individual, family, and drug environment characteristics. The theories of anomie, socialization, social control, and differential association are used as a guide for these examinations. The data for this study were collected from a sample of 604 students from 16 classes in three grades at five schools using a self-administrated questionnaire designed for this purpose. These classes were randomly selected from all 85 junior high schools which were stratified by …

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Xanthomonas Albilineans Detection, Identification And Infectivity Titration In Sugarcane., Silvio Aparecido Lopes Jan 1996

Xanthomonas Albilineans Detection, Identification And Infectivity Titration In Sugarcane., Silvio Aparecido Lopes

LSU Historical Dissertations and Theses

A PCR method with primers for t-RNA gene spacers was used for detection of Xanthomonas albilineans (Xa), the causal agent of leaf scald disease of sugarcane. A DNA segment of approximately 170 bp was amplified for Xa strains, but also for X. campestris pv. campestris, X. campestris pv. translucens and two sugarcane bacterial endophytes. Good agreement between PCR and isolation to detect Xa from sugarcane sap was observed. PCR was faster allowing pathogen detection in less than one day. Both methods resulted in low detection frequencies from asymptomatic plants, which may contain Xa below detection limits. The lowest limit for …

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American Literary Environmentalism, 1637-1872., David Mazel Jan 1996

American Literary Environmentalism, 1637-1872., David Mazel

LSU Historical Dissertations and Theses

The American environment is a mythic narrative that has served to mystify the social and economic relationships linking people and place. This study examines the early writing of the environment, from the 1637 Pequot War to the creation of the first national parks in the late nineteenth century. Chapter 1 draws on the work of Michel Foucault and Edward Said to theorize "literary environmentalism" as a knowledge-power formation that functions as a domestic Orientalism. Chapter 2 theorizes the narratological and psychosociological bases of environmental constructions generally before analyzing two colonial texts whose literary environmentalism is paradigmatic: John Underhill's Newes from …

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Biological Control Of Pythiaceous Fungi Causing Death Of Longleaf Pine Seedlings During Cold Storage., Xiaoan Sun Jan 1996

Biological Control Of Pythiaceous Fungi Causing Death Of Longleaf Pine Seedlings During Cold Storage., Xiaoan Sun

LSU Historical Dissertations and Theses

Pythium dimorphum Hendrix & Campbell and other Pythium species were determined to be pathogenic fungi that cause the death of longleaf pine seedlings during cold storage. Pathogenicity of these Pythium isolates as determined by infecting newly-germinated slash pine seedlings in vitro was confirmed in field evaluations. An in vitro dual culture screening system was effectively used for selecting Trichoderma isolates capable of killing P. dimorphum. Selected Trichoderma isolates and Gliocladium virens produced volatile and/or non-volatile antibiotics on solid media and in liquid cultures, but antibiotic production could be affected by medium type, pH, and culture age, depending on species or …

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An Attempt To Classify The Production And Regulation Of Cyclooxygenase-2 During Ovulation And Luteolysis., James Robert Broussard Jan 1996

An Attempt To Classify The Production And Regulation Of Cyclooxygenase-2 During Ovulation And Luteolysis., James Robert Broussard

LSU Historical Dissertations and Theses

A series of experiments were designed to determine the cyclooxygenase (COX) isoform responsible for prostaglandin release during ovulation and luteolysis. Initially, a reliable, serum-free culture system was developed to produce large numbers of bovine granulosa cells originally harvested from the small antral follicles of abattoir ovaries. This method allowed adequate numbers of cells to be obtained for the subsequent study involving cyclooxygenase regulation. In a second experiment, bovine granulosa cells from small antral follicles were isolated and cultured as in the first experiment for 6 days. Granulosa cells were then exposed to medium alone or medium containing arachidonic acid (10 …

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Deaf Students In Mainstreamed College Composition Courses Culture And Pedagogy., Tonya Stremlau Johnson Jan 1996

Deaf Students In Mainstreamed College Composition Courses Culture And Pedagogy., Tonya Stremlau Johnson

LSU Historical Dissertations and Theses

Composition theorists have already considered the effect of cultural constructs on writing students and have modified pedagogical practices to meet the needs of diverse students. However, disability has remained an almost invisible category in composition studies. This is unfortunate because our society has historically limited the access of the disabled into society, including the academy. Composition teachers need to understand deafness because poor English literacy skills are one culturally constructed attribute associated with hearing loss. The need is especially great now that legal and social developments are encouraging more deaf students to enroll in hearing majority colleges. Also, high-level literacy …

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The Effect Of Membrane Structure On Lipid Peroxidation And Its Inhibition., Tammy Renee Dugas Jan 1996

The Effect Of Membrane Structure On Lipid Peroxidation And Its Inhibition., Tammy Renee Dugas

LSU Historical Dissertations and Theses

Lipid peroxidation is the process by which lipids in the cell membrane undergo free radical-initiated oxidation. The resulting cell damage has been implicated in the onset of many diseases, including as cancer, aging, and stroke. Lipid oxidation has been studied in a variety of membrane models, including homogeneous solution, micelles, liposomes, and microsomes. The kinetics for free radical reactions proven to occur during lipid oxidation in homogeneous solution have been thoroughly elucidated. These kinetics were also shown to apply to oxidation in micelles. This dissertation presents evidence that the kinetics of more biologically realistic membrane models such as liposomes may …

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Regulation Of Interrenal Steroidogenesis In Elasmobranchs., Brian Scott Nunez Jan 1996

Regulation Of Interrenal Steroidogenesis In Elasmobranchs., Brian Scott Nunez

LSU Historical Dissertations and Theses

This study investigated the steroidogenic enzymes of the elasmobranch interrenal. First, biochemical characteristics of cytochrome P450c21 hydroxylase (P450c21) and 3$\beta$-hydroxysteroid dehydrogenase (3$\beta$-HSD) were determined with incubations of the microsomal fraction of Carcharhinus limbatus (blacktip shark) interrenal tissue. Second, molecular reagents were obtained by isolating and sequencing partial cDNA clones encoding the elasmobranch steroidogenic enzymes cytochrome P450 side chain cleavage (P450scc) and 3$\beta$-HSD from blacktip shark and Daysatis americana (southern stingray) interrenal. Finally, the regulation of Daysatis sabina (Atlantic stingray) interrenal steroidogenesis by peptide hormones such as corticotropin (ACTH) and angiotensin II was investigated by in vitro incubations of interrenal tissue. …

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Ion Transport In The Freshwater Bivalve, Corbicula Fluminea (Muller)., Huiyuan Zheng Jan 1996

Ion Transport In The Freshwater Bivalve, Corbicula Fluminea (Muller)., Huiyuan Zheng

LSU Historical Dissertations and Theses

Corbicula fluminea (Muller) maintains hydromineral balance in dilute media by active transepithelial transport of Na and Cl. Cl uptake depended on external (Cl) and displayed saturable kinetics. The transport capacity in pondwater(PW)-acclimated animals was 7.00 $\pm$ 0.51 $\mu$eq(g dry tissue $\cdot$ h)$\sp{-1}$ and the transport affinity 0.21 $\pm$ 0.08 mM. Prolonged salt depletion increased Cl transport capacity without changing the affinity. In PW-acclimated C. fluminea, Na and Cl transport were independent, and were stimulated by serotonin. In salt depleted (SD)animals, Na transport was partially Cl-dependent but Cl transport was Na-independent. Acetazolamide increased Na and Cl efflux. Both serotonin and acetazolamide …

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Border Crossers And Coyotes: A Reception Study Of Latin American And Latina/O Literatures., Delia Maria Poey Jan 1996

Border Crossers And Coyotes: A Reception Study Of Latin American And Latina/O Literatures., Delia Maria Poey

LSU Historical Dissertations and Theses

Since the 1970s, there has been an ongoing debate within the humanities regarding the canon and curricular reform. Moving beyond questions of advocacy and the dichotomy of center and periphery (without diminishing the necessity of these), Border Crossers and Coyotes: A Reception Study of Latin American and Latina/o Literatures surveys the various ways which marginalized texts enter U.S. academic discourse as well as analyzing the conflicts inherent in these border crossings. The study proposes the position of the coyote, a person who transports undocumented workers across the U.S./Mexico border for profit, as analogous to that of the critic/teacher. Employing a …

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The Increase In Shaft Capacity With Time For Friction Piles Driven Into Saturated Clay., Hani Hasan Titi Jan 1996

The Increase In Shaft Capacity With Time For Friction Piles Driven Into Saturated Clay., Hani Hasan Titi

LSU Historical Dissertations and Theses

A general method for predicting pile setup, or the increase in the load carrying capacity of friction piles driven into saturated clay, was developed. The solution is based on the HiSS modeling approach, the strain path method, and the theory of nonlinear porous media. The ability of this method was demonstrated by predicting the field behavior of pile segment models during driving, subsequent consolidation, and load testing. Numerical simulations were performed on pile segment models because of the availability of field experimental tests necessary for verification and evaluation schemes. The method was also applied to investigate the behavior of full-scale …

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Tertiary Recovery Of Oil By Up-Dip Gas Injection., Tammy Theresa Bourgoyne Jan 1996

Tertiary Recovery Of Oil By Up-Dip Gas Injection., Tammy Theresa Bourgoyne

LSU Historical Dissertations and Theses

A tertiary gas injection process denotes the mobilization of waterflood residual oil by gas invasion; whereas, secondary gas injection denotes the displacement of a continuous oil phase by gas. The term up-dip gas injection implies that the gas is injected in the crest of the structure in order to displace fluid down-dip where it can be recovered in a production well; whereas, an attic oil recovery process usually implies a cyclic injection/recovery process using a single well. The objective of this study is to develop a technique for modelling relative permeability in a tertiary gas injection process occurring in a …

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Influence Peddling And The Municipal Market: An Investigation Of Political Contributions And Accounting Disclosures., Steven M. Filling Jan 1996

Influence Peddling And The Municipal Market: An Investigation Of Political Contributions And Accounting Disclosures., Steven M. Filling

LSU Historical Dissertations and Theses

The municipal bond market is widely perceived to be amenable to influence peddling between parties to bond transactions. One of the primary concerns of both regulators and investors is the relationship between political contributions by bond market participants and the volume and profitability of bond market business engaged in by those participants. This study uses publicly available data from the state of Louisiana to provide evidence concerning the relationship between contributions made by bond market participants and bond business awarded or influenced by recipients of those contributions. Contributions by bond market players to officials likely to possess influence over bond …

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Extraction And Analysis Of Triazines In Fish Tissues Following A Toxic Exposure: Environmental Factors Affecting Atrazine Toxicity In Fish., Patricia Simmons Gaunt Jan 1996

Extraction And Analysis Of Triazines In Fish Tissues Following A Toxic Exposure: Environmental Factors Affecting Atrazine Toxicity In Fish., Patricia Simmons Gaunt

LSU Historical Dissertations and Theses

Rapid, generic, and environmentally friendly methods for extraction and detection of the pesticides atrazine, cyanazine, metribuzin, and simazine were developed for use in monitoring the cause of pesticide related or suspect fish kills. Further, environmental hypoxia and elevated temperature were studied as possible contributors to the toxicity of atrazine in channel catfish (Ictalurus punctatus) and as synergistic factors to be considered in investigating fish kill events. Incurred residues from the exposure of catfish to atrazine alone or hypoxia or elevated temperature and atrazine were also analyzed. A commercial enzyme-linked immunoassay (ELISA) was utilized as a screening method for the presence …

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Dinitropyrenes: Nitroreduction Processes And Evaluation Of Indices Of Exposure., Matthew Jerome Krautmann Jan 1996

Dinitropyrenes: Nitroreduction Processes And Evaluation Of Indices Of Exposure., Matthew Jerome Krautmann

LSU Historical Dissertations and Theses

Investigations were conducted to identify biomarkers of exposure to dinitropyrenes (DNPs), which are mutagenic and carcinogenic residues of incomplete combustion. One possible biomarker, a DNP-protoporphyrin IX adduct, was not found in analytically useful quantities in liver tissue or in bile. Clastogenicity, a biomarker of effect, also was found to be absent in marrow cells following subchronic exposure of rats to DNPs by gavage. Solubility studies, used as a basis for dosing guidelines, revealed that DNPs are relatively insoluble in both aqueous and lipid tissue compartments. Calculated log P values indicated that the reduced metabolites of DNPs probably are more soluble …

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Characterization Of Physiological Changes In Roots Grown In Spaceflight Conditions: A Comparison Of Nutrient Delivery Technologies., David Marshall Porterfield Jan 1996

Characterization Of Physiological Changes In Roots Grown In Spaceflight Conditions: A Comparison Of Nutrient Delivery Technologies., David Marshall Porterfield

LSU Historical Dissertations and Theses

The best strategy for providing food and maintaining the environment on long-duration space missions is a bioregenerative life support system based on the growth of higher plants. Before such a system can be implemented, a better understanding of plant growth in space will have to be achieved. Little is known about the role of gravity-dependent physical processes in normal physiological function. A series of ground-based and spaceflight experiments was conducted to examine root oxygen availability in microgravity nutrient delivery systems. In spaceflight experiments Arabidopsis thaliana (L.) Heynh. plants were analyzed for changes in root medium redox potential and root alcohol …

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Using Interactive Desk-Top Videoconferencing As A Distance Learning Tool For Program Development And Support: An Ethnographic Case Study Of Two Family Literacy Sites., Geetanjali Soni Jan 1996

Using Interactive Desk-Top Videoconferencing As A Distance Learning Tool For Program Development And Support: An Ethnographic Case Study Of Two Family Literacy Sites., Geetanjali Soni

LSU Historical Dissertations and Theses

This ethnographic study provides a description and analysis of the use of videoconferencing to teach an eight-week parenting class to parents enrolled in two family literacy programs. It describes the sites, details interactions that take place during videoconferencing, and investigates parents affective response to the technology. Data were collected through participant observation, interviews, video-recordings, and questionnaires. Results indicated cross-site differences in the existing program, in affective responses of users, and in interactions during the technology-mediated classes. Findings showed that the parenting classes were successful. Factors that influence effectiveness of videoconferencing instruction are discussed. Results indicated that technological factors such as …

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A Cyclic Plasticity/Damage Model For Metal Matrix Composites., Ganesh Thiagarajan Jan 1996

A Cyclic Plasticity/Damage Model For Metal Matrix Composites., Ganesh Thiagarajan

LSU Historical Dissertations and Theses

A new six parameter general anisotropic yield surface using a fourth order anisotropic tensor $M\sb{ijkl}$ has been proposed. This form has been derived based on the physical behavior observed for the material under consideration--directionally reinforced metal matrix composites. Its validity has been shown by proving its convexity and form under coordinate transformation. This form of the anisotropic yield function is general in nature which can be used for either pressure dependent or independent cases. The proposed surface compares well with the extensive experimental data of Dvorak et al. (1988) and Nigam et al. (1993) performed on boron-aluminum metal matrix composite. …

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A Feasibility Study Of Using Air-Lift Pumps For Aeration, Degasification, And Water Movement In A Recirculating Aquaculture System, John Clay Loyless Dec 1995

A Feasibility Study Of Using Air-Lift Pumps For Aeration, Degasification, And Water Movement In A Recirculating Aquaculture System, John Clay Loyless

LSU Historical Dissertations and Theses

A feasibility study of using air-lift pumps for water movement, aeration, and degasification in a recirculating aquaculture system was conducted. Fluid delivery tests of various air-lift configurations indicated that water flow is a function of the submergence depth, lift height, and air injection rate. The air-lift units were found to transfer 02 at only 1/5 to 1/2 the rate of comparably operated open-water aeration systems. The standard oxygen transfer rate (SOTR) increased with air injection from 1-7 scftn, however, the energy usage also increased, yielding a reduction in the standard aeration efficiency (SAE) from over 2 to less than 0.5 …

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