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Water Quality Impacts From Agricultural Land-Use In The Karst Groundwater Basin Of Qingmuguan, Chongqing, China, Ted W. Baker Dec 2008

Water Quality Impacts From Agricultural Land-Use In The Karst Groundwater Basin Of Qingmuguan, Chongqing, China, Ted W. Baker

Masters Theses & Specialist Projects

Karst regions are composed of soluble rock, often limestone, which leads to the formation of fissures, sinkholes and water flow conduits such as caves. Pollutants in karst waters tend to be quickly directed and concentrated into these subsurface conduits. As a result of this and other factors, water resources are especially sensitive to contamination and pollution in karst areas. Pollutant concentrations going into fluvial systems travelling through the subsurface in karst areas are often very similar to the concentrations arriving at outlets such as springs. Areas connected by karst conduit flows must be distinctly determined and special attention should be …


Atrazine Contamination And Suspended Sediment Transport Within Logsdon River, Mammoth Cave, Kentucky, Julie Eileen Schenck Brown Dec 2008

Atrazine Contamination And Suspended Sediment Transport Within Logsdon River, Mammoth Cave, Kentucky, Julie Eileen Schenck Brown

Masters Theses & Specialist Projects

Understanding the potential for karst aquifer contamination by sediment-sorbed pesticides is important for cave conservation efforts in agricultural landscapes. Flow rate, water quality parameters and suspended sediment concentrations were measured in Logsdon River, a ~10km karst conduit within the Turnhole Spring Groundwater Basin of Mammoth Cave National Park to determine characteristics of storm-period transport of sediment-sorbed atrazine through a conduit-flow karst aquifer.

Analysis of two independent precipitation events occurring in the Spring of 2008 from May 2-4 and May 27-29 demonstrated the rapid response of the Logsdon River to precipitation events with detections of atrazine increasing during the initial turbidity …


The Application Of Electrical Resistivity And Microgravity To Locate Tunnels Along The U.S.-Mexico Border At Calexico, Gina Lee Cesin Dec 2008

The Application Of Electrical Resistivity And Microgravity To Locate Tunnels Along The U.S.-Mexico Border At Calexico, Gina Lee Cesin

Masters Theses & Specialist Projects

No abstract provided.


Simulation Modeling Of Karst Aquifer Conduit Evolution And Relations To Climate, John D. Broome Dec 2008

Simulation Modeling Of Karst Aquifer Conduit Evolution And Relations To Climate, John D. Broome

Masters Theses & Specialist Projects

ABSTRACT Karst regions of the world that receive relatively similar amounts of precipitation display a wide variety of landscapes. It has been suggested (Groves and Meiman, 2005) that climates exhibiting larger discrete storm events have more dissolving power and consequently higher rates of conduit growth than climates with more uniform precipitation distributions. To study this concept, a computer program “Cave Growth” was developed that modeled the growth of a cross-section of a cave passage under dynamic flow and chemical conditions. A series of 46 simulation datasets were created to represent different climatic conditions. These simulations had the same total annual …


Watershed Condition Assessment For Little River Canyon National Preserve, Alabama, Nathan Demille Rinehart Dec 2008

Watershed Condition Assessment For Little River Canyon National Preserve, Alabama, Nathan Demille Rinehart

Masters Theses & Specialist Projects

No abstract provided.


A Selectivity Study On The Use Of Caffeine And Theobromine Imprinted Polypyrrole Surface Electrodes, Anil Kiran Kumar Vinjamuri Aug 2008

A Selectivity Study On The Use Of Caffeine And Theobromine Imprinted Polypyrrole Surface Electrodes, Anil Kiran Kumar Vinjamuri

Masters Theses & Specialist Projects

Molecularly imprinted polymers (MIPs) are proving to be very effective in development of synthetic recognition systems and are of great interest to those interested in the field of sensor technology. The use of MIPs is receiving considerable interest due to the ability to prepare recognition matrices that possess high substrate selectivity and specificity. Conducting polymers (CP) have proved to be an excellent tool for the preparation of nano-structured biologically selective systems. Polypyrrole (Ppy) is one such CP that is extensively used for the construction of bioanalytical sensors. Ppy has shown great promise primarily due to its biocompatibility and thermal stability …


Admicelle-Based Solid Phase Extraction Of Phenols Using Dialkylammonium Surfactant In The Hydroxide Form, Kali R. Pickering Aug 2008

Admicelle-Based Solid Phase Extraction Of Phenols Using Dialkylammonium Surfactant In The Hydroxide Form, Kali R. Pickering

Masters Theses & Specialist Projects

A technique for admicelle-based solid phase extraction is presented in which a dialkylammonium surfactant in the hydroxide form is immobilized on silica. By converting dihexadecyldimethylammonium bromide to the hydroxide form, the surfactant is allowed to have the property of a strong base, aiding in the extraction of acidic phenols which are difficult to extract because of their differing polarities. The surfactant-silica admicelle parameters were optimized for the efficient extraction of eight phenols. Adsorbed phenols were eluted from the sorbent using small volumes of methanol. The phenols were preconcentrated from drinking water samples and were determined using high performance liquid chromatography …


Proposed Route To Cyclopenta[C]Thiophenes Via Activated Methylene, Vineet V. Karambelkar Aug 2008

Proposed Route To Cyclopenta[C]Thiophenes Via Activated Methylene, Vineet V. Karambelkar

Masters Theses & Specialist Projects

The synthesis of cyclopenta[c]thiophenes has been sparsely reported in the literature owing to several difficulties involved in their synthesis. The present work involves the proposed synthesis of cyclopenta[c]thiophenes and their precursors using activated methylene. Cyclopenta[c]thiophene compounds show promise in the field of polymer and catalysis chemistry. These substituted polythiophenes are potential organic semiconductors and anti-tumor agents. The research presented shows the successful and novel conversion of 3,4-bis(chloromethyl)-2,5-dimethylthiophene and 3,4-bis(bromomethyl)-2,5-dimethylthiophene to a fused 5,5'-fused membered ring which is the precursor to cyclopenta[c]thiophene the sulfone ester, 5-carbomethoxy-5- phenylsulfonyl-1,3-dimethyl-5,6-dihydro-4H-cyclopenta[c]thiophene, in just two steps as compared to four steps previously reported in the literature. …


A Study On The Protein Interaction With Different Platinum Compounds, Nayna Kotadia Jul 2008

A Study On The Protein Interaction With Different Platinum Compounds, Nayna Kotadia

Masters Theses & Specialist Projects

Since the discovery of anti-tumor activity of cisplatin in 1960, significant progress has been made in treating metastatic or advanced cancer with cisplatin and platinum compounds. Platinum compounds covalently bind to DNA and disrupt DNA function. They are also known to bind with amino acids like methionine, histidine and cysteine to form cisplatin-protein adducts which are responsible for most of its cytotoxicity and side effects. Recent articles on cisplatin-protein have shown that adding bulky adjuncts to cisplatin or using different platinum compounds varies the degree and extent of reaction thus possibly reducing cisplatin resistance and side effects.

One of the …


Optimization Of Microwave-Assisted Acid Digestion Method For Determination Of Trace Elements In Coal And Coal Fly Ash, Dejan Savic Jul 2008

Optimization Of Microwave-Assisted Acid Digestion Method For Determination Of Trace Elements In Coal And Coal Fly Ash, Dejan Savic

Masters Theses & Specialist Projects

In most of the analytical and environmental laboratories today inductively coupled plasma (ICP) is a method of choice for analysis of trace metal elements present in coal and coal combustion products. This method requires use of liquid samples, so all coal and coal combustion products must be digested prior to analysis by ICP. Traditionally an open-air hot-plate acid digestion method published as ASTM D6357-04 was used to extract all trace metal elements into solution.

Recent development of microwave systems designed for digestions under extreme acidic conditions and high temperatures and pressures shifted focus toward more rapid and precise microwave-assisted digestion …


Calculus Of Variations On Time Scales And Its Applications To Economics, Chris Mcmahon May 2008

Calculus Of Variations On Time Scales And Its Applications To Economics, Chris Mcmahon

Masters Theses & Specialist Projects

The goal of time scale research is to progress the development of a harmonized theory that is all encompassing of the more commonly known specialized forms. The main results of this paper is the presentation of the Ramsey model which can be written using both the A and V operators, and solved using the two separate theories of the calculus of variations on time scales. The next presentation will be of the solution of an adjustment model, for a specific form of a time scale, whose functional can only be optimized, using the existing theory, when written with the A …


Chemistry And The Automotive Industry, Jeremy Pedigo May 2008

Chemistry And The Automotive Industry, Jeremy Pedigo

Masters Theses & Specialist Projects

This thesis covers the use of chemistry in the automotive industry with emphasis on environmental compliance via chemical reporting by database and internal Energy Dispersive X-ray Fluorescence (XRF) screening, third party laboratory material testing, and the future of the chemist in the United States (U.S.) automotive industry. The third party testing was performed at Western Kentucky University (WKU) via the Materials Characterization Center (MCC), Institute for Combustion Science and Environmental Technology (ICSET) Thermodynamics Laboratory, and using the Scanning Electron Microscope/Energy Dispersive X-ray Spectrometer (SEM/EDX) managed by the WKU Biotechnology Center. Furthermore, the tests conducted were used to investigate material defects, …