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Environmental Chemistry

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Articles 1351 - 1380 of 1490

Full-Text Articles in Chemistry

Remote Sensing Of Railroad Locomotive Emissions: A Feasibility Study, Peter J. Popp, Gary A. Bishop, Donald H. Stedman Jan 1999

Remote Sensing Of Railroad Locomotive Emissions: A Feasibility Study, Peter J. Popp, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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Identification Of Polluting Vehicles By Remote Sensing, Donald H. Stedman Jan 1999

Identification Of Polluting Vehicles By Remote Sensing, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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Monitoring The Effects Of Indoor Pollution Using Fourier Transform Infrared Spectroscopy, Rachel Farrell Jan 1999

Monitoring The Effects Of Indoor Pollution Using Fourier Transform Infrared Spectroscopy, Rachel Farrell

Presidential Scholars Theses (1990 – 2006)

Fourier Transform Infrared Spectroscopy {FTIR) was used to develop an effective way to monitor indoor pollution and to observe the effects of such indoor pollution under various conditions of the ventilation system of McCollum Science Hall of the University of Northern Iowa, Cedar Falls, Iowa. This was done by monitoring the absorbance of acetone as it evaporated over time, and the data were used to create concentration vs. time plots. Several parameters from these plots were used to judge the ventilation system, with some general conclusions including that having the system on reduces peak time and end time. Also, the …

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Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority Oct 1998

Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority

Publications (WR)

A number of agencies sample Lake Mead and the Las Vegas Wash on a routine basis at several locations. In order to share and properly interpret the data, the Bureau of Reclamation, Southern Nevada Water Authority and the three Wastewater Treatment Facilities (City of Las Vegas, Clark County Sanitation District and City of Henderson) formed a committee to examine sampling and analytical protocols and to share information with the goal of maximizing the data quality. The group first met in April 1997. It was agreed that an effort should be made to discuss and compare specific sampling and analytical techniques …

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Influences Of Acid Mine Drainage On Water Chemistry Of Blackwater River Watershed, Carla C. Morato-Lara Jan 1998

Influences Of Acid Mine Drainage On Water Chemistry Of Blackwater River Watershed, Carla C. Morato-Lara

Theses, Dissertations and Capstones

Acidic mine drainage flow from active and abandoned coal mines has been a major source of water pollution in the Appalachian Mountain region of the eastern USA. Water samples were collected and analyzed from Blackwater River watershed during 2 years (September 1996 - May 1998). The water quality measurements determined that the Beaver Creek and North Fork tributaries were affected by acid mine drainage but not Yellow Creek. Beaver Creek and North Fork stations had high sulfate and manganese markers of acid mine drainage, whereas Yellow Creek was slightly acidic with low sulfate and manganese. North Fork was the primary …

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On-Road Remote Sensing Of Heavy-Duty Diesel Truck Emissions In The Austin- San Marcos Area: August 1998, Jerome A. Morris, Gary A. Bishop, Donald H. Stedman Jan 1998

On-Road Remote Sensing Of Heavy-Duty Diesel Truck Emissions In The Austin- San Marcos Area: August 1998, Jerome A. Morris, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Year 1, Peter J. Popp, Gary A. Bishop, Donald H. Stedman Jan 1998

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Year 1, Peter J. Popp, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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Final Technical Report For Its For Voluntary Emission Reduction: An Its Operational Test For Real-Time Vehicle Emissions Detection, Gary A. Bishop, Donald H. Stedman, R. Bruce Hutton Jan 1998

Final Technical Report For Its For Voluntary Emission Reduction: An Its Operational Test For Real-Time Vehicle Emissions Detection, Gary A. Bishop, Donald H. Stedman, R. Bruce Hutton

Fuel Efficiency Automobile Test Publications

No abstract provided.

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1998 Preliminary Snowmobile Emission Survey In Yellowstone National Park, Gary A. Bishop, Donald H. Stedman Jan 1998

1998 Preliminary Snowmobile Emission Survey In Yellowstone National Park, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller Jan 1998

Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study shows that chemical properties of two restiad species, Empodisma minus and Sporadanthus traversii, may contribute to their success as peat-formers in a climate of the North Island of New Zealand which is not conducive to raised mire development. Unlike Sphagnum, the equivalent northern hemisphere peat-former, restiads possess lignin in their tissues. In addition, the presence of non-lignin polyphenols (including tannins and phenolic acids) in restiads may be an important factor in peat formation due to the allelopathic decay retardation. Patterns of degradation of plant biopolymers have been examined and the pathway of degradation of monocotyledons (loss …

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A Molecular Evaluation Of Contaminants And Natural Organic Matter In Surface Sediments From Western Lake Ontario, Michael A. Kruge, Prasanta K. Mukhopadhyay, C.F. Michael Lewis Jan 1998

A Molecular Evaluation Of Contaminants And Natural Organic Matter In Surface Sediments From Western Lake Ontario, Michael A. Kruge, Prasanta K. Mukhopadhyay, C.F. Michael Lewis

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) analysis of bottom sediment from Lake Ontario was shown to be effective in assessing organic contaminants, especially attractive as it is a rapid technique requiring little sample preparation. Pyrolyzates of samples richer in organic matter (OM) were relatively enriched in aliphatic hydrocarbons and pyrrolic nitrogen compounds, while leaner samples were more aromatic and pyridinic. Alkylbenzene and alkylphenol distributions in the pyrolyzates were most compatible with derivation from aquatic (algal, bacterial) OM. The organonitrogen compounds indicated the presence of degraded proteinaceous material from aquatic sources and/or sewage. Normal and polycyclic aromatic hydrocarbon distributions indicate, at least in …

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Remote Sensing Of Commercial Aircraft Emissions, Peter J. Popp, Donald H. Stedman Jan 1998

Remote Sensing Of Commercial Aircraft Emissions, Peter J. Popp, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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A Study Of Polycyclic Aromatic Hydrocarbons During Combustion In An Afbc System, Laura Dicken Dec 1997

A Study Of Polycyclic Aromatic Hydrocarbons During Combustion In An Afbc System, Laura Dicken

Masters Theses & Specialist Projects

The purpose of this study was to develop the on-line method of analysis which leads to the study of polycyclic aromatic hydrocarbons (PAHs) during combustion in an atmospheric fluidized bed combustor (AFBC) system. The study of PAHs is important because they may be produced upon the combustion of coal. The US EPA prioritizes PAHs as major pollutants due to their mutagenic and carcinogenic effects. Standards of PAHs were analyzed by injection into the gas chromatograph-mass spectrometer (GC-MS). These standards were then analyzed using the on-line method. Two coals were burned in the AFBC system and effluent samples were collected. These …

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Evaluation Of The Natural Biodegradation Of Aircraft Deicing Fluid Components In Soils, Laura M. Johnson Dec 1997

Evaluation Of The Natural Biodegradation Of Aircraft Deicing Fluid Components In Soils, Laura M. Johnson

Theses and Dissertations

This research effort was conducted to analyze the biodegradation of propylene glycol (PG) and tolyltriazole in two different soil types; a sandy soil and a high clay soil. Both an automated respirometer and a high performance liquid chromatograph (H PLO) were used in the analysis. Two separate experiments were conducted. In the first experiment, one level of tolyltriazole was added to the soils to determine whether or not there was a difference in the biodegradation rates of tolyltriazole in the two soils. The respirometer results indicated that there was a significant difference between the respiration rates of the microorganisms in …

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A Modeling Study For The Implementation Of In Situ Cometabolic Bioremediation Of Trichloroethylene-Contaminated Groundwater, John A. Christ Dec 1997

A Modeling Study For The Implementation Of In Situ Cometabolic Bioremediation Of Trichloroethylene-Contaminated Groundwater, John A. Christ

Theses and Dissertations

The limitations of conventional groundwater remediation technologies have led to the development of innovative technologies which may achieve national hazardous waste site remediation goals. Before an innovative technology can be implemented in the field, remedial project managers, regulators and other stakeholders require adequate modeling tools to help assess the applicability of the technology at a particular site. This modeling study investigates how an innovative technology, in situ cometabolic bioremediation, might be implemented to remediate a TCE-contaminated site, under different site conditions. A steady-state model is developed which couples an analytical expression to simulate the effect of flow between multiple pumping …

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Modeling The Uptake And Transpiration Of Tce Using Phreatophytic Trees, Douglas P. Wise Dec 1997

Modeling The Uptake And Transpiration Of Tce Using Phreatophytic Trees, Douglas P. Wise

Theses and Dissertations

Phytoremediation is a recent addition to the numerous methods used today to remediate ground water contaminants. It is proving more effective and efficient compared to existing remediation techniques. The use of phreatophytes, or water seeking trees, has great potential for phytoremediation. These trees are fast growing, long lived, grow their roots down to the ground water table, transpire large amounts of water, and are proven to actively remove contaminants from the soil horizon. The purpose of this research is to develop quantitative concepts for understanding the dynamics of TCE uptake and transpiration by phreatophytic trees over a short rotation woody …

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Estimation Of Groundwater Velocities From Yucca Flat To The Amargosa Desert Using Geochemistry And Environmental Isotopes, Ronald L. Hershey, Steve Y. Acheampong Jun 1997

Estimation Of Groundwater Velocities From Yucca Flat To The Amargosa Desert Using Geochemistry And Environmental Isotopes, Ronald L. Hershey, Steve Y. Acheampong

Publications (WR)

Geochemical modeling techniques were applied to groundwater flowpaths from Yucca Flat on the Nevada Test Site (NTS) to the Amargosa Desert, south of the NTS to estimate groundwater flow velocities for independent comparison to velocities calculated by other methods. The groundwater flowpaths examined considered flow in the carbonate aquifer beneath Yucca and Frenchman flats mixing with flow from carbonate aquifers east and southeast of the NTS and discharging at wells south of the NTS border. The approach used the computer codes WATEQ4F and NETPATH to calculate chemical speciation, determine the saturation state of mineral phases, and simulate mixing and the …

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On-Road Co, Hc, No And Opacity Measurements (Presentation), Donald H. Stedman, Gary A. Bishop, Phillip Aldrete Jan 1997

On-Road Co, Hc, No And Opacity Measurements (Presentation), Donald H. Stedman, Gary A. Bishop, Phillip Aldrete

Fuel Efficiency Automobile Test Publications

No abstract provided.

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Application Of Environmental Organic Petrology And Geochemistry To Fingerprint Organic Pollutants In The Recent Sediments Of Lake Ontario, Prasanta K. Mukhopadhyay, Michael A. Kruge, C.F. Michael Lewis Jan 1997

Application Of Environmental Organic Petrology And Geochemistry To Fingerprint Organic Pollutants In The Recent Sediments Of Lake Ontario, Prasanta K. Mukhopadhyay, Michael A. Kruge, C.F. Michael Lewis

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Selected surface sediment samples (sediment depth 0-10 cm) collected in the Niagara basin (western Lake Ontario) were chosen for organic matter characterization using organic petrological and geochemical techniques normally reserved for the study of coal, petroleum source rock and crude oil. The study was performed to assess the effectiveness of these techniques in discriminating between natural and anthropogenic organic matter and to determine the extent of organic pollution of the lake sediments. The organic carbon contents of the samples vary from 1.5 to 3.5%, with upper layer (0-5 cm) samples have higher TOC values than those from the lower layer …

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Development Of A High-Speed Ultraviolet Spectrometer, Capable Of Real-Time No And Aromatic Hydrocarbon Detection In Vehicle Exhaust (Presentation), Peter J. Popp, Gary A. Bishop, Donald H. Stedman Jan 1997

Development Of A High-Speed Ultraviolet Spectrometer, Capable Of Real-Time No And Aromatic Hydrocarbon Detection In Vehicle Exhaust (Presentation), Peter J. Popp, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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The Biodegradation Characteristics Of Proposed Fuel Systems Icing Inhibitors (Fsii), Charles E. Meshako Dec 1996

The Biodegradation Characteristics Of Proposed Fuel Systems Icing Inhibitors (Fsii), Charles E. Meshako

Theses and Dissertations

The biodegradation characteristics of three fuel system icing ihhibitors (FSII) were evaluated. FSII are jet fuel additives that partition into water readily and are present in the water drained from storage tank bottoms in concentrations approaching 40%. These concentrations raise concerns as to the disposal and handling of these wastes. The current FSII, DiEGME was evaluated along with two new candidates, dipropylene glycol and glycerol formal. DiEGME appeared to be moderately but not completely biodegradable. It is likely that much of it would be removed in a wastewater treatment plant. Dipropylene glycol only showed signs of degradation after more than …

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Mass Transport Of Volatile Organic Compounds Between The Saturated And Vadose Zones, Monte S. Harner Dec 1996

Mass Transport Of Volatile Organic Compounds Between The Saturated And Vadose Zones, Monte S. Harner

Theses and Dissertations

Volatile organic compounds (VOCs) dissolved in the saturated zone are transported into the vadose zone primarily by gaseous phase diffusion. If the saturated zone is remediated, VOCs present in the vadose zone may become a secondary source of contamination for the groundwater. The amount of VOCs that remain in the vadose zone is dependent on site hydrology, soil properties, and the chemical properties of the contaminants. The purpose of this study was to determine what conditions caused VOC concentrations in the vadose zone to significantly recontaminate the saturated zone. A one-dimensional numerical model was developed to investigate the transport of …

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Modeling Marine Exposure To Polychlorinated Biphenyls From Sunken Ships, Charles N. Wendt Dec 1996

Modeling Marine Exposure To Polychlorinated Biphenyls From Sunken Ships, Charles N. Wendt

Theses and Dissertations

In the past, the U.S. Navy has routinely conducted SINKing EXercises (SINKEX) for training, weapon effectiveness tests, and economic disposal of aging assets. Recent concern over polychlorinated biphenyl (PCB) chemicals aboard such target vessels has resulted in a suspension of SINKEX. The U.S. Navy has approximately 200 vessels currently requiring such disposal. Environmental legislation and health concerns preclude selling such vessels to foreign governments or scrapping. This work attempted to model the fate and transport of these PCBs by examining their transport to coastal water and their accumulation in the marine food chain. The model includes biodegradation, upwelling, partitioning of …

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Concentrations, Complexation And Speciation Of Total Dissolved Zinc In The Chesapeake Bay, Charles William Henry Iii Jul 1996

Concentrations, Complexation And Speciation Of Total Dissolved Zinc In The Chesapeake Bay, Charles William Henry Iii

Chemistry & Biochemistry Theses & Dissertations

This is the first research to examine the horizontal, vertical, and temporal variability of total dissolved zinc, organic complexation of zinc, and zinc speciation in the Chesapeake Bay. Filtered (0.45μm) surface and bottom water samples were taken along the salinity gradient of the Chesapeake Bay in October 1993, March 1995, July 1995, and October 1995. Analysis by Differential Pulse Anodic Stripping Voltammetry (DP ASV) indicated that total dissolved zinc concentrations in the Bay ranged from 2.9 ± 0.7nM to 38.8 ± 2nM. Total zinc was highest at the northern end of the Bay (low salinity), approximately 10 times lower at …

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Isolation From Soil Microorganisms That Are Inhibitory To Wheat Seeding Pathogens, Kynita Wilson-Humphrey May 1996

Isolation From Soil Microorganisms That Are Inhibitory To Wheat Seeding Pathogens, Kynita Wilson-Humphrey

McCabe Thesis Collection

Many diseases caused by bacteria, viruses, or fungi are responsible for the ruin of a great number of crops annually. At present, many of these crops are being treated for diseases by synthetic or man-made chemicals. Some of the chemicals have been proved to have adverse effects on the environment, including humans and animals. Very few non-chemical means are available to farmers at this time to control these pathogens. This is due to the fact that many of the means of control have little effect against the pathogens or diseases. This research attempts to isolate microorganisms from the soil which …

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Carbon Monoxide Amongst Other Chemicals (Presentation), Donald H. Stedman Jan 1996

Carbon Monoxide Amongst Other Chemicals (Presentation), Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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Flash Pyrolysis Of Anthropogenic And Natural Organic Matter In Polluted Sediments, Sami T. Abdel Bagi, Michael A. Kruge, Gary L. Salmon Jan 1996

Flash Pyrolysis Of Anthropogenic And Natural Organic Matter In Polluted Sediments, Sami T. Abdel Bagi, Michael A. Kruge, Gary L. Salmon

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

INTRODUCTION - Combustion products along with spilled petroleum and industrial chemicals contribute to environmental degradation by contaminating soils and sediments. Such anthropogenic organic matter (OM), if preserved in sediments, can serve an archival function, documenting the local, history of industrial pollution. Christensen and Zhang (1993) determined the sources of polycyclic aromatic hydrocarbons (P AH) to Lake Michigan from sedimentary records, finding that coal combustion was a major source for PAHs in these sediments. Bodzek and Luks-Betlej (1993) reported that atmospheric deposition is the main source of PAH in soils of the heavily industrialized Upper Silesia region of Poland. Smith and …

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Epa Overestimates The Benefit Of Biennial Inspection And Maintenance, Donald H. Stedman Jan 1996

Epa Overestimates The Benefit Of Biennial Inspection And Maintenance, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

The United States Environmental Protection Agency (EPA) computer model of mobile source emissions is used to estimate the benefits of future emissions control programs. Four input assumptions are discussed, each of which tends to overestimate the benefits of biennial testing programs. The assumptions are: each model year drives the same number of miles; high/superemitters, absent initially, increase linearly with mileage; inspection and maintenance (I/M) readings are invariant, and I/M repairs last forever. States opting for these programs should be aware that the predicted benefits may not materialize.

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Model Of Chlorocarbon (Cfc-12) Chemisorption On Solid Rocket Motor Alumina Exhaust Particles, Gary E. Lund Dec 1995

Model Of Chlorocarbon (Cfc-12) Chemisorption On Solid Rocket Motor Alumina Exhaust Particles, Gary E. Lund

Theses and Dissertations

Solid Rocket (SRMs) that power Titan IV rockets and Space Shuttles, exhaust large quantities of potentially ozone damaging pollutants directly into the stratosphere, while in powered flight. In the past, studies on potential stratospheric impact of the exhaust products from aluminum/ammonium perchlorate based SRMs have focused on the effect of gaseous HCl from SRMs on the stratosphere. Until recently, the impact of heterogeneous chemistry on stratospheric ozone was believed to be relatively insignificant. This research investigates the potential heterogeneous process of CFC-12 dissociative chemisorption on alumina surfaces and the release of reactive halogen species known to destroy ozone. Through a …

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Effects Of Ammonium Perchlorate On The Thyroid Hormone Levels Of The Sprague-Dawley Rat, James H. King Jr. Dec 1995

Effects Of Ammonium Perchlorate On The Thyroid Hormone Levels Of The Sprague-Dawley Rat, James H. King Jr.

Theses and Dissertations

The purpose of this research was to determine the threshold dose for ammonium perchlorate (AP) in the Sprague-Dawley rat. No dose response data exist for AP and the EPA has studied literature on the subject of perchlorates to determine a provisional reference dose. The Perchiorate Group, a consortium of DoD and industry representatives, believes this provisional reference dose is too conservative. This experiment was executed to provide dose response data on which to base a more accurate reference dose. The study consisted of eight groups of 12 Sprague-Dawley rats, six male and six female, which were exposed to incremental doses …

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