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Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX

Description: The City of Denton Pecan Creek Wastewater Treatment Facility has periodically failed effluent toxicity testing. A Toxicity Identification Evaluation has determined that Diazinon in the effluent is contributing to the observed toxicity. Chlorpyrifos is also implicated as a factor. The City of Denton constructed a half acre experimental wetland to remove Diazinon related toxicity. Results from spiking and microcosm experiments indicate that the wetland can reduce the Diazinon.
Date: May 1996
Creator: Baerenklau, Amy L. (Amy Lyn)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A Comparison of Predicted and Actual Trophic Status of Lake Ray Roberts, Texas Based on Chlorophyll A

Description: Two years before impoundment, the trophic status of Lake Ray Roberts was predicted by applying the total phosphorus input into the Organization for Economic Cooperation and Development (OECD) eutrophication model. Predicted mean summer epilimnetic (MSE) chlorophyll a of Elm Fork arm, Isle duBois arm and Main Body were in the eutrophic category of the OECD model. Observed MSE chlorophyll a two years after impoundment of Elm Fork arm, Isle duBois and Main Body had not reached their predicted mean… more
Date: May 1999
Creator: Lytle, Lili Lisa
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Assessment of Changes in Aquatic Macrophyte Occurrence Following Introduction of Triploid Grass Carp in a North Texas Reservoir

Description: The objectives of this project were to measure changes in frequency of occurrence of submerged macrophytes over the first two growing seasons following stocking with triploid grass carp at two fish per acre and to measure differences in macrophyte biomass between areas excluded from herbivory and adjacent control sites after 16 months following establishment of exclosures. The project also seeks to measure concentrations of fluridone following the herbicide treatment, and to compare two methods… more
Date: August 1997
Creator: Bickel, Ken (Kenneth E.)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Genetic Variation in a Population of the Plains Woodrat Neotoma micropus

Description: Neotoma micropus from Jack County, Texas, were studied over a 9-month period. Loci from blood and saliva were used to determine genetic variation within the population. Deviations from Hardy-Weinberg equilibrium were found at one locus. The average temporal F over all seven loci was 0.040. Genetic structuring was subtle, fluctuated on a seasonal basis, and was due to differential migration or predation on genotypes. Heterozygotes tended to move more than homozygotes, and a greater proportion of… more
Date: August 1988
Creator: Stewart, John E. B. (John Edward Bakos)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Estimated Extent and Fate of Chlorinated Solvent Contamination in the Soil of the Naval Air Station, Dallas, Texas

Description: This thesis estimates the spatial extent of chlorinated solvent contamination of the soil at the Naval Air Station, Dallas, then estimates the fate and transport of these contaminants, over time, using the Soil Transport and Fate database and the Vadose-Zone Interactive Processes (VIP) modeling software. Geostatistical analysis identifies two areas with serious chlorinated solvent contamination. Fate and transport modeling estimates that this contamination will degrade and disperse from the soi… more
Date: August 1998
Creator: Trescott, Jill V. (Jill Virginia)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Response of Aquatic Insect Communities and Caged In situ Asiatic Clams (Corbicula fluminea) to Dechlorinated Municipal Effluent in the Trinity River in North Texas

Description: Dischargers to the Trinity River in North Texas were required to dechlorinate their effluents in 1990-91. Field surveys were conducted above and below an outfall to determine the response of resident immature insects and caged in situ juvenile Asiatic clams to chlorinated and dechlorinated effluent. Within six months after dechlorination began, insect community composition and C. fluminea survival significantly improved at stations below the outfall. Significantly lower clam growth within one m… more
Date: December 1994
Creator: Spon, Sandra T. (Sandra Teresa)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Use of Similarity Indicies to Assess the Spatial Differences of the Phytoplankton Communities in Lake Ray Roberts, Texas

Description: A study of the phytoplankton communities of Lake Ray Roberts was conducted at three sampling sites on two sampling dates during the summer of 1995, assessing both community structure and chlorophyll a concentrations. Eight similarity indices were then used to characterize and compare the communities of these sites. Both community similarity and chlorophyll a concentrations were evaluated using a minimum detectable difference equation to determine the amount of change that must occur in these pa… more
Date: August 1996
Creator: Banks, Kenneth E. (Kenneth Edward)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Sanitary Aspects of Milk and Dairy Products Dispensed in Sherman, Texas

Description: The aim of this investigation is to determine whether there is a correlation between the sanitary condition of milk and dairy products dispensed in Sherman, Texas, and the plate counts, the morphology, and the Gram stain reaction of the organisms in predominant colonies from these.
Date: 1948
Creator: Bryant, J. Forrest
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Age and Rate of Growth of the Black Crappie, Pomoxis Nigro-Maculatus (Le Sueur), and the White Crappie, Pomoxis Annularis Rafinesque, in the Koon Kreek Klub Lakes, Texas

Description: This study is another phase of the overall research program designed to furnish basic information for the management of East Texas lakes and has as its specific purpose the determination of the age and growth characteristics of two valuable species on these waters. The species to be considered are the black crappie, Pomoxis nigro-maculatus (Le Sueur) and the white crappie, Pomoxis annularis Rafinesque. Both species are highly regarded as food fish and have for many years offered recreational ou… more
Date: 1948
Creator: Elliott, James M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Taxonomic Significance of the Foliar Epidermal Hairs of Several Families of Dicotyledons

Description: The present investigation deals with the study of non-glandular epidermal hairs from the leaves of two hundred representative dicotyledons of forty-eight families in the Central North Texas area. Special attention has been given to the Compositae and Leguminosae in an effort to find a possible correlation between epidermal hair morphology and the taxonomic position of the plants concerned.
Date: 1945
Creator: McCarty, Faye A.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Seasonal Variations in Microflora of Four Denton County, Texas, Clay Soils

Description: This investigation has for its aim the confirmation of the correlation between soil moisture and the microflora of soils, and a lesser relation between the soil temperature and the microflora. The soils used in this study are typical clay soils of Denton County, Texas. The samples were taken from virgin pasture lands and analyses made monthly or semimonthly. The wide seasonal variation of temperature and rainfall afford a good opportunity for this study.
Date: 1941
Creator: Manire, Philip
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Food Habit Analysis of the Two Species of Texas Crappie

Description: This study is based upon information taken from stomach analysis of 302 black crappie and 561 white crappie; the following data will be presented: 1. Food of adults and fingerlings; 2. Diet variation in relation to food availability; 3. Seasonal variation of feeding habits; 4. Diet variation in relation to size of crappie. Collections were made from ten lakes located in North, East, Central, and South Texas.
Date: 1941
Creator: Mitchell Glenn C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Phototropic Properties of Lactuca Ludoviciana (Nutt.) DC. and Silphium Laciniatum L.

Description: This paper deals with certain phases of phototropic properties of two exceptional plants, the pertinent behavior of each being decidedly individualistic and in remarkable contrast to that of herbaceous plants in general. The prickly lettuce, Lactuca ludoviciana (Nutt.) DC. and the rosinweed, Silphium laciniatum L., two common Denton County, Texas, plants, have been selected for this study.
Date: 1941
Creator: Neal, George C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Bacterial Survey of the Sources of Drinking Water of Trinidad, Texas, with Special Reference to Sanitation

Description: A bacterial analysis of the water from thirty-six sources of consumption by the white population of Trinidad, Henderson County, Texas, was made to determine the potability of each of these in regard to infection from typhoid or related organisms.
Date: 1944
Creator: Coldwell, Lavenia Ruth
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Sanitary Aspects of the Swimming Pool of North Texas State Teachers College, Denton, Texas

Description: This investigation was conducted in order to show that insanitary conditions may exist in the swimming pool at North Texas State Teachers College provided the proper precautions are not taken; and, in contrast that this pool can be sanitary and entirely safe when operated and used according to the necessary sanitary specifications.
Date: 1943
Creator: Self, Louise
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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