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Development of a Watershed Prioritization Strategy Using Remote Sensing and the Geographic Resource Analysis Support System. Case study: City of Carrollton, Texas (open access)

Development of a Watershed Prioritization Strategy Using Remote Sensing and the Geographic Resource Analysis Support System. Case study: City of Carrollton, Texas

This study used a geographic information system (GIS) and an empirical pollutant load model to estimate average annual pollutant loads contained in storm water charges from the City of Carrollton, Texas. The Geographic Resource Analyses Support System (GRASS) was used to create a number of spatial data layers as input variables to a model that estimates loads in Kilograms/Hectare/Year, and Kilogram/Basin/Year. Average annual pollutant loads for twelve pollutants were derived from average annual rainfall/runoff volumes, coupled with Local Dallas/Fort Worth Metroplex storm water Event Mean Concentrations.
Date: December 1996
Creator: Coffey, Jeffery M. (Jeffery Morgan)
System: The UNT Digital Library
The Removal of Linseed Oil Vapors by Biodegradation (open access)

The Removal of Linseed Oil Vapors by Biodegradation

Linseed oil is very important in industry but its use is limited due to noxious vapors produced by oxidation on exposure to air. Since some of the products are toxic, release of linseed oil vapors to the environment is normally prohibited. In order to remove the odorous compounds, a biofilter system based on bacterial metabolism was designed and the major premises of bioremediation were studied. A total of five bacterial strains capable of using linseed oil vapors as their sources of carbon and energy were isolated from soil. The individual organisms were also mixed to form a bacterial consortium. The mixed population was able to degrade linseed oil vapors with more than 99 per cent efficiency. According to this research, a successful biodegradation system was designed and, theoretically, this system could be applied to the removal of linseed oil vapors in any industrial plant air stream.
Date: August 1996
Creator: Sukplang, Patamaporn
System: The UNT Digital Library
The Use of Similarity Indicies to Assess the Spatial Differences of the Phytoplankton Communities in Lake Ray Roberts, Texas (open access)

The Use of Similarity Indicies to Assess the Spatial Differences of the Phytoplankton Communities in Lake Ray Roberts, Texas

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 parameters in order to be deemed statistically significant. The Bray-Curtis Index was shown to be the most adequate index evaluated, and was subsequently used in conjunction with bootstrap analysis to determine the similarity between the three sampling sites.
Date: August 1996
Creator: Banks, Kenneth E. (Kenneth Edward)
System: The UNT Digital Library
Comparison of Remediation Methods in Different Hydrogeologic Settings Using Bioplume II (open access)

Comparison of Remediation Methods in Different Hydrogeologic Settings Using Bioplume II

A contaminant fate and transport computer model, Bioplume II, which allows simulation of bioremediation in ground water systems, was used to compare the effects of 11 remediation scenarios on a benzene plume. The plume was created in three different hydrogeologic settings from the simulation of an underground gasoline storage tank leak.
Date: May 1996
Creator: White, Sherry A. (Sherry Anne)
System: The UNT Digital Library
Evaluating Fish Impingement and Entrainment at the Comanche Peak Steam Electric Station (open access)

Evaluating Fish Impingement and Entrainment at the Comanche Peak Steam Electric Station

This study was designed to determine if impingement and entrainment by cooling water intake at the Comanche Peak Steam Electric Station have an adverse impact upon the Squaw Creek Reservoir fish population. The yearly impingement of fish was estimated to be 262,994 of 14 species. The threadfin shad (Dorosoma petenense) accounted for 96% of this total. Entrainment of eggs and larvae for a five month period was estimated to be 15,989,987 and 42,448,794 respectively. Two fish population studies were performed on Squaw Creek Reservoir to help assess impact. It was determined that the losses due to impingement and entrainment have no adverse impact upon the fish population of Squaw Creek Reservoir.
Date: May 1996
Creator: Bauml, George A. (George Arthur)
System: The UNT Digital Library
Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX (open access)

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

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)
System: The UNT Digital Library
Nucleotide Sequence of a Bovine Arginine Transfer RNA Gene (open access)

Nucleotide Sequence of a Bovine Arginine Transfer RNA Gene

A single plaque-pure lambda clone designated λBA84 that hybridized to a ˆ32P-labeled bovine arginine tRNA was isolated from a bovine genomic library harbored in a lambda bacteriophage vector. A 2.3-kilobase segment of this clone was found to contain an arginine transfer RNAccg gene by Southern blot hybridization analysis and dideoxyribonucleotide DNA sequencing. This gene contains the characteristic RNA polymerase III split promoter sequence found in all eukaryotic tRNAs and a potential RNA polymerase III termination site, consisting of four consecutive thymine residues, in the 3'-flanking region. Several possible cis-acting promoter elements were found within the 5'-flanking region of the sequenced gene. The function of these elements, if any, is unknown.
Date: May 1996
Creator: Eubanks, Aleida C. (Aleida Christine)
System: The UNT Digital Library
Short Term Effects of External Electric Fields on Electrical Activity of the Pineal Gland in Rats (open access)

Short Term Effects of External Electric Fields on Electrical Activity of the Pineal Gland in Rats

The effects of short term exposure (5 minutes) to EEFs at relatively high dosages (10, 25, 39, kV/m) on the electrical activity in rat pineal glands was studied. Daytime and nighttime recordings were taken from an implanted microelectrode in the gland. The data show that (1) both the activity and frequency were enhanced when the animals were exposed to EEFs at 39 kV/m continuously and discontinuously; (2) the later condition yielded a sustained increase (36%) whereas the former a brief (10 sec) increase. This enhancement was statistically significant under both conditions (day and night). The effects observed were thought to be due to membrane alterations either in the pineal gland itself or in the neural inputs to the gland.
Date: May 1996
Creator: Vu, Hung Quoc
System: The UNT Digital Library