Environmental Chemistry Commons^™

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Year 4, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Los Angeles Area: Year 2, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Interpreting Remote Sensing Nox Measurements (Presentation), Robert Slott, Donald H. Stedman, Sajal S. Pokharel

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Year 2, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Phoenix Area: Year 2, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Fuel-Based On-Road Motor Vehicle Emissions Inventory For The Denver Metropolitan Area (Presentation), Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Fuel-Based On-Road Motor Vehicle Emissions Inventory For The Denver Metropolitan Area, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Motor Vehicle Emissions Measurments Worldwide (Presentation), Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

How To Evaluate An On-Road Remote Sensor, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Preliminary Studies Using Remote Sensing To Evaluate I/M Effectiveness, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Biogeochemistry And Contaminant Geochemistry Of Marine And Estuarine Sediments, New Haven, Connecticut (Usa), Michael A. Kruge, Gaboury Benoit

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The urbanized shore areas of Long Island Sound in the vicinity of New Haven, Connecticut (USA) have a long history of exposure to point and non-point sources of pollution, New Haven having been one of the birthplaces of the industrial revolution. As an unintended consequence of such activities, the region's sedimentary systems have incorporated a complex mixture of organic and inorganic contaminants. With its long and varied pollution history and the multiplicity of sedimentary environments (fluvial, estuarine, intertidal, marsh, etc.) present in a compact geographical area, the region is ideal natural laboratory for field testing new contamination assessment techniques. The …

Binding Of Pb And Zn To Aluminium Oxide And Proton Stoichiometry, Wing H. Leung, A. Kimaro

Virginia Journal of Science

The interaction of Pb and Zn with Al₂O₃ in aqueous solution was studied as a function of pH and metal ion concentration. Results indicated the complexation of metal ions by oxide surfaces is strongly pH dependent; the extent of adsorption is a function of pH with an abrupt change within approximately 2 pH units. The adsorption of Pb and Zn on aluminium oxide can be interpreted in terms of a surface complexation formed by association with one surface AlOH group, thus releasing one bound hydrogen ion. -AlOH + M²⁺ = -AlOM⁺ + H⁺ . …

In Situ Treatment Of Chlorinated Ethene-Contaminated Groundwater Using Horizontal Flow Treatment Wells, Derek R. Ferland

Theses and Dissertations

The limitations of conventional containment technologies for groundwater contaminated with chlorinated solvents have motivated development of innovative technologies to achieve national groundwater remediation objectives. One inn9vative technology that is currently under development involves metal reductants or catalysts to chemically destroy the dissolved chlorinated solvent. Models are important tools that can be used to help transition this technology to the field. Model studies can be used to gain understanding about the technology, help determine when the prospective technology might work for a given site, and design full-scale field applications.

Modeling Chlorinated Ethene Removal In Constructed Wetlands: A System Dynamics Approach, Colby D. Hoefar

Theses and Dissertations

The purpose of this study is to gain understanding of the dynamics of the processes that degrade Perchloroethene (PCE) to ethylene, or carbon dioxide (CO₂), within the confines of a constructed wetland. A system dynamics approach will be used. This model is focused on identifying and optimizing the naturally occurring processes in stratified wetland sediment that reduce mass, toxicity, mobility, volume or concentration of contaminants in groundwater. Contaminant fate and transport within a wetland system is extremely complex and the mechanisms that drive wetland behavior are dynamic. Confidence in the model was built through verification and testing. Reasonable …

Chromate Dissociation From Primer Paint In Simulated Lung Fluid, Tiffany J. R. Morgan

Theses and Dissertations

OSHA has proposed a new strontium chromate exposure standard that would potentially cause Air Force paint facilities to be in violation of the proposed standard if adopted. This proposed reduction make the continued use of chromate containing primer paints very difficult. There is currently no acceptable replacements for chromate containing primer paints on AF aircraft. This study suggests that paint particles with chromate bound in primer paint may be unavailable for bodily absorption if inhaled and a reduced standard for painting applications may be unnecessary. Primer paint overspray was collected into simulated lung fluid (SLF) and allowed 6 hr, 24 …

Parameters Influencing Sediments Resuspension And The Link To Sorption Of Inorganic Compounds, Eid A. Alkhatib, Keith Castor

Chemistry & Physics Faculty Publications

In the aquatic environment, the accumulation of chemicalcontaminants by sediments poses a potential threat to endemiclife forms and drinking water resources. Trace metals such asCd, Cu, Cr, Ni, Pb, and toxic organic compounds, are among awide variety of contaminants having an affinity for sediments.In this study, experiments were performed simulating sedimentresuspension in the lower Housatonic River, Connecticut, using aParticle Entrainment Simulator. Analyses of grain sizedistributions, porosities and total organic contents of thesediments suggested that these parameters influence theredistribution and entrainment of settleable solids in the watercolumn. These findings were established by evaluating the impactof one parameter on sediment resuspension as …

Direct Titrimetric Determination And Of Sulphate, Chee Kin Tan

Student Works (2000-2009)

Interference by foreign ions in direct titrimetric determination of sulphate with barium perchlorate using dimethylsulphonazo III (DMSA Ill) as indicator were studied in this research project. The use of certain water miscible solvents as titration medium has enhanced the determination of end-point. Among the methanol, ethanol, n-propanol and acetone used in the investigation, it was found that medium containing 40 to 50% n-propanol or acetone delivered distinct end-points. The effects of nine cations and eight anions were studied in the above sulphate titration. It was found that the interference caused by Li",Na",K",Mg2"·Mn2", Cd2", NH4", CI and Br are not significant. …

Rsd Versus Im240 Fleet Average Correlations, Sajal S. Pokharel, Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

Analysis Of Remote Sensing Data For Development Of I/M Program Evaluation Protocols, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

New Emission Test Would Cost More, Do Less, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Surrounding Denver Metro Smart Sign Study Summer 2000, Michael Duncan

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Year 3, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Los Angeles Area: Year 1, Gary A. Bishop, Sajal S. Pokharel, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Humic Substances As Interferences In The Analysis Of Nitrite In Water, Stephanie Ann Tebault

Chemistry & Biochemistry Theses & Dissertations

Humic substances are of current interest because of their roles in environmental processes involving pollutants. It is also becoming recognized that humic substances may interfere in analysis of environmental samples though the possible adverse effects do not appear to be fully appreciated. The present effort focuses on determining whether humic materials interfere in the analysis of nitrite in water using the Griess reaction. This is a well-known reaction using nitrosation to gjve a diazonium salt followed by coupling with an appropriate reagent to form a dye. This colorimetric method continues to be applied in the laboratory and the field for …

Zinc Speculation And Ligand Fluxes In Chesapeake Bay And Elizabeth River Pore Waters, Duncan Glover Byers

Chemistry & Biochemistry Theses & Dissertations

Presented here are the first data on the vertical concentrations, complexation, speciation, and fluxes of total dissolved zinc and zinc complexing ligands, and zinc speciation in sediment pore waters in the Chesapeake Bay and Elizabeth River, Virginia.

Sediment pore waters were collected in mid and southern Chesapeake Bay in November 1997 and in the Elizabeth River (Pinner's Point) in March, April, and July 1998. Flux experiments were conducted in Elizabeth River sediment cores in April and July 1998. [TDZn] and zinc complexation were determined using differential pulse anodic stripping voltammetry at a hanging mercury drop electrode (DPASV-HMDE).

[TDZn] in the …

The Binding Of Selected Xenoestrogens To An Estrogen-Binding Fraction, Willie L. Washington

Electronic Dissertations and Theses

The purpose of this study was to test the hypothesis that effects of xenoestrogens may be mediated through a low-affinity estrogen-binding site. This low-affinity estrogen-binding site (EBS) is found in rat uterus. A second receptor, the Type I-(high-affinity-EBS). is also present in the uterus and other tissues. In order to obtain the estrogen-binding fraction-from the uterus, an ammonium sulfate (AS) fractionation was performed on rat-uterine cytosol. Two fractions were made, a 40% AS, which contained the Type I estrogen receptor (ER) and a 70¾ AS fraction that contained the low-affinity estrogen-binding site. These fractions were assayed for their ability to …

Identification And Characterization Of Biological And Volatile Organic Contaminants In Indoor Air In A Governmental State Office Building, Denesia A. Wallace

Electronic Dissertations and Theses

The purpose of this study was to identify and determine the concentrations of targeted inorganic gases and total volatile organic compounds known to exist in indoor air spaces. The Louisiana Department of Environmental Quality (LADEQ) Office Building was selected because of a survey of occupants' symptoms and perceptions of indoor air quality. Collected air samples were analyzed for selected compounds by way of United States Environmental Protection Agency (USEPA) sampling procedures and methods that utilized drager absorption tubes and a gas chromatograph/mass spectrometer. The targeted compounds were nitrogen dioxide, dinitrogen oxide, carbon monoxide, VOCs (volatile organic compounds), formaldehyde, and carbon …

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 …

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.

Rsd Studies In Austin, 1998, Sajal S. Pokharel, Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.