Thesis (Ph. D.)--University of Wisconsin--Madison, 1981. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 121-130).

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6546. Adviser: Prasanta K. Kalita. Includes bibliographical references (leaves 229-257) Available on microfilm from Pro Quest Information and Learning.

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6585. Adviser: Marcelo H. Garcia. Includes bibliographical references (leaves 134-143) Available on microfilm from Pro Quest Information and Learning.

Thesis (Ph. D.)--University of Illinois at Urbana-Champaign, 2006. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6253. Adviser: Susan M. Larson. Includes bibliographical references (leaves 238-245). Available on microfilm from Pro Quest Information and Learning.

Recently, there has been an increased concern of the potential effects of pharmaceuticals, personal care products (PPCPs) and endocrine disrupting compounds (EDCs) in drinking water. Their presence in surface waters has resulted in the skewing of sex ratios in aquatic biota and the effect on humans, as yet, remains unknown. Investigation into the effective removal of these compounds by water treatment plants (WTPs) has shown that conventional treatment processes are not very effective in removing these trace compounds. Studies have shown PPCPs and EDCs have been successfully removed by commercial nanofiltration (NF) and reverse osmosis (RO) membranes, but have low flux and high cost. North American WTPs, using membrane separation processes, are typically equipped with microfiltration (MF) or loose ultrafiltration (UF) membranes which, thus far, have proven ineffective for the removal of these target compounds. This thesis focuses on the development of a tight charged UF membrane that effectively removes PPCPs and EDCs from drinking water while still maintaining a high flux and is cost effective. Novel membranes were developed by incorporating charged surface modifying macromolecules (CSMMs) in the manufacturing of polyether sulfone (PES) based membranes. The charged additives were expected to enhance the removal of PPCPs and EDCs by charge repulsion. Controls and three different CSMM (DEG-HBS, DEG-HBC and PPG-HBC) blended membranes were prepared at three different casting conditions and subsequently evaluated for various properties: flux, molecular weight cut-off (MWCO), porosity, charge and contact angle. Experimental membranes were further evaluated for the removal of four representative target compounds, sulfamethazine (SMZ), carbamazepine (Carb), bisphenol A (BPA) and ibuprofen (IB). Removal by a commercial nanofiltration membrane, NF270 (DOW/FilmTec) was compared to the experimental membranes. Removal results from the experimental membranes indicate membranes were unable to sustain effective removal of the target compounds. Typically, removal was initially high but decreased over the run. Membrane characteristics showed membranes had significantly larger pores than the target compounds indicating size exclusion was not the removal mechanism. Charge results indicated CSMM blended membranes were generally unchanged from the control membrane indicating, in addition to the unsustained removal, that charge repulsion was not the removal mechanism. From the shape of the removal curves, it is assumed the removal mechanism is the result of membrane adsorption. The CSMMs were found to have modified the membranes, though not sufficiently, to be considered significantly different than the controls in many respects. Membrane characteristics varied as a result of each CSMM incorporated and depending on each casting condition. Contact angle results for both PES-DEG-HBS and PES-PPG-HBC membranes at all three casting conditions increased in comparison to the controls, presumably because of changes in surface roughness. PES-DEG-HBC, on the other hand, decreased in contact angle at 18%, and increased in contact angle at 20% in comparison to the respective controls. Incorporation of migration time, particularly in the case of DEG-HBC, increased membrane flux without affecting MWCO. Increased PES concentration (from 18 to 20%) saw an increased target compound removal. With the success of the DEG-HBC CSMM, incorporation of migration time at higher PES concentrations appears promising for achieving the desired characteristics. It is recommended that further optimization using CSMM DEG-HBC at increased PES concentrations with migration time be investigated for this application.

In September 2005, Health Canada took on the development of a Source Water Quality Indicator for Canada. The main objective was to develop a methodology by which source water quality could be linked to public health, the environment, society, and economy; and measured, tracked, and reported in the form of an indicator for decision making. A Treated Water Quality Indicator was also introduced to bridge the gap between source water quality and human health. With Federal/Provincial/Territorial and academic support, research into the approach and development of a conceptual design, parameter selection rationale, and two tools for the indicator calculations, along with recommendations for future work were completed. The tools developed included a modified Canadian Council of Ministers of the Environment water quality index calculator, and a Treatability Ranking tool (that determined the complexity of treatment required to achieve safe drinking water). The results of this project are described herein.

<p> Coastal erosion is an issue of concern for Louisiana, in the United States, and for all other coastal communities in the world. Among many coastal protection and restoration technologies, shoreline protection structures focus on wave reductions to prevent waves from hitting the coastal landforms directly. A novel technology called the Wave Suppression and Sediment Collection (WSSC) system focuses on solving the limitations of conventional shoreline protection structures regarding mobility, constructability, and sustainability. The primary goals of this study are to optimize the WSSC units for wave reduction and sediment transport and to verify the performance of this technology in an actual field environment. Computational Fluid Dynamics (CFD) simulations were carried out to optimize the designs of the units in terms of pipe diameters and face slope. Results have indicated that increasing pipe diameters decreases wave reduction and increases sediment transport ability of the units. Further, it was found that increasing the face slope decreases the wave reduction ability; however, no effect was found on the sediment transport efficiency. Parametric optimization suggested that a porosity (open-to-total area ratio) of 30% should yield satisfactory wave reduction and balanced sediment transport by the units. For better output from the units, the designs should be modified according to site-specific requirements. Field site investigations involved Surface Elevation Table (SET) surveying and marker clay experiments. SET surveys showed significant sediment accumulation over eleven months behind the units. Also, no significant change was observed at the control site over three months, which proves the effectiveness of the technology in stopping erosion and facilitating land building. Marker clay experiments validated the SET measurements and proved that there was a significant amount of sediment deposition over the white Feldspar clay layer over six months. This strengthens the conclusion that the WSSC units can be used successfully in a Louisiana marsh environment to battle coastal erosion and land loss.</p><p>

<p> Chemical and petrochemical industries produce substantial amounts of wastewater every day. This wastewater contains organic pollutants such as benzene, toluene, ethylbenzene and xylenes (BTEX) that are toxic to human and aquatic life. Ordered Mesoporous Carbon (OMC), an adsorbent that possesses the characteristics of an ideal adsorbent was investigated to understand its properties and suitability for BTEX removal. Adsorption isotherms, adsorption kinetics, the effects of BTEX initial concentrations, and temperatures on the adsorption process were studied. The OMCs were characterized using surface area and pore size analyzer, transmission electron microscopy (TEM), elemental analysis, thermogravimetric analysis (TGA), and fourier transform infrared spectroscopy (FTIR). The results suggested that the Langmuir isotherm and pseudo-second-order models described the experimental data. The thermodynamic parameters, Gibbs free energy (&Delta;G), the enthalpy change (&Delta;H), and the entropy change (&Delta;S) of adsorption indicated that the adsorption processes were physical, endothermic, and spontaneous. In addition, OMC had 27% higher total adsorption capacities compared to GAC. Physical modifications on OMC were performed by varying the ratios of boric acid to sucrose. The BTEX adsorption capacities were improved from 8% to 15% with the addition of boric acid. The highest total adsorption capacity was 116.6 mg g^-1 using OMC-2. Chemical modification of OMC using citric acid showed increase in adsorption capacity by 21.7% compared to OMC-2.</p><p>

Greenhouse gas emission magnitudes, trends, and source contributions are highly uncertain, particularly at sub-national scales. As the world becomes increasingly urbanized, one potential strategy for reducing these uncertainties is to focus atmospheric greenhouse gas measurements in urban areas, where a multitude of emission processes occur, imposing a strong and persistent gradient in the local atmosphere, and contributing a significant fraction of global anthropogenic greenhouse gas emissions. This thesis explores the capabilities and requirements for characterizing and quantifying greenhouse gas fluxes in urban environments using atmospheric measurements and models. The first chapter uses an existing dataset of atmospheric carbon dioxide measurements from Salt Lake City, Utah to assess the capacity of an atmospheric measurement and modeling framework to detect changes in emissions from a city in the context of an emissions verification framework. The results of this work are then used to explore an alternative or complementary measurement strategy of atmospheric column measurements for urban emissions detection, which would be less sensitive than point measurements to the large variability present in urban atmospheres, but would also have more stringent accuracy requirements. The second chapter describes the development and maintenance of a network of greenhouse gas measurement stations in the Boston urban region, which has been continuously running since 2012 and has generated high-quality atmospheric carbon dioxide and methane data that can be used to explore their fluxes across the urban region. The third chapter applies the Boston network data to investigate the magnitude of methane emissions from natural gas infrastructure in the urban region. We find that the natural gas loss rate in 2012-13 was 2.7 ± 0.6 %, two to three times larger than that reported by industry and government. Our findings suggest that natural gas consuming regions may be larger sources of methane than previously thought, and have implications for local and national policies that aim to reduce methane emissions and promote energy-use efficiency. The work presented in this thesis explores general methodological strategies for urban atmospheric measurements and models, and offers example applications of such methods to directed and societally-relevant investigations of urban greenhouse gas emissions. / Engineering and Applied Sciences - Engineering Sciences

The physicochemical properties of the secondary organic materials (SOMs) that constitute the particle phase have potentially important consequences for the growth, the reactivity, and ultimate fate of atmospheric organic aerosols, thereby affect climate, human health and visibility. A quantitative analysis of the physicochemical properties of the SOMs is important, but challenging. This thesis presents laboratory studies of α-pinene derived SOMs, which is one of the major components of secondary organic aerosols (SOAs) in the forests, by combing a flow tube reactor, aerosol particle mass analyzer (APM) and other online/offline measurement techniques. A water-jacketed constant temperature flow tube reactor was built to produce SOM particles grown from either condensation or coagulation. Different ratios of α-pinene enantiomers were mixed and injected into the flow tube reactor for dark ozonolysis. A matrix of organic precursor and ozone concentrations was designed and tested in order to determine the optimal concentration to switch between condensation and coagulation. Results show that at 51 ± 1 ppm O3, condensation is the dominant growth mechanism when the α-pinene concentration is 0.125 ± 0.001 ppm, and coagulation is the dominant growth mechanism when the α-pinene concentration increases to 1.00 ± 0.03 ppm. A combination of both growth mechanisms is observed when the α-pinene concentration is in between the described values. The study also proposed and tested the hypothesis that a 50:50 mixture of α-pinene enantiomers may result in SOM particles that have different physical properties, such as number-diameter distributions, when compared with those particles generated from a single enantiomer of α-pinene. The experiment was conducted within the condensational growth regime so that the chirality induced structure differences in oligomers can be maximized during the nucleation and condensation. Nevertheless, our analysis indicates that, after removing the effects of ozone and temperature, the chirality-induced effects are minimal and within our detection limit. Even though the results were negative, the method used in this experiment provided useful experience for the viscosity related experiments in this thesis. Another important property of the SOM is its viscosity. The viscosities of atmospheric particles determine whether their interactions with surrounding gases are confined to the surface or can proceed to the interior. Viscosities affect the gas-particle diffusion rate, and ultimately influences the SOM’s other physical properties, such as particle size, and chemical properties, such as reactivity. The work presented in this thesis estimates the viscosity of submicron organic particles while they are still suspended as an aerosol without further post-processing techniques that can have the possibility of altering the properties of semivolatile materials. The results show that the studied particles are semisolid up to 58% relative humidity (RH) and may become liquid only at a higher RH. These results imply that atmospheric particles, at least those similar to the ones studied and for low to middle RH regimes, are expected to reach equilibrium only rather slowly with the chemical composition of the gas phase, sometimes on timescales longer than the actual residence time of the particles in the atmosphere. Last but not the least, the results of offline particle analysis from two collaboration studies are also discussed in this thesis. The results show how water vapor, or RH, affects the physicochemical properties of the α-pinene derived SOM particles. In one study, the diffusivity is underestimated by approximately 8 orders of magnitude if calculated from the Stokes-Einstein equation, which suggests the breakdown of Stokes-Einstein equation for small gas molecules. The second study shows the surface properties of SOM particles can be influenced by the RH, leading to a difference of the gas-particle interactions at the particle surface. / Engineering and Applied Sciences - Engineering Sciences