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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Bench- and Pilot-Scale Corrosion Control Inhibitor Effectiveness Studies for a Community's Blended Surficial and Brackish Groundwater Supply

Campesino, Paula 01 January 2023 (has links) (PDF)
The United States Environmental Protection Agency regulates the lead and copper content of a public water system's finished water at the consumer's tap, through the Safe Drinking Water Act's Lead and Copper Rule (LCR), promulgated in 1991. This rule was recently changed through the LCR Revisions (LCRR), that took effect in 2021. The more stringent requirements of the LCRR motivated the City of Sarasota, Florida (City), to work with the University of Central Florida (UCF) on a study of the municipality's finished water corrosivity. Initially, this evaluation investigated the City's existing finished water corrosivity using linear polarization resistance (LPR) measurements and gravimetric coupon analysis at the pilot-scale, during which four phosphate-based inhibitors were tested for corrosion control. Based on the initial screening results, the City challenged UCF to derive a cost-effective, bench-scale method that could mimic distribution system conditions and be used to assess treatment technology infrastructure changes on finished water corrosivity. A modified corrosion jar test was developed that compared metal release of a high and low total dissolved solids water. The modified bench-scale method that omitted the effects of zero headspace using a sealed environment was found to be an improvement over conventional jar testing techniques. The results of the bench-scale experiments demonstrated the effectiveness and reproducibility of the modified method, as confirmed through analyses of variance. The modified bench-scale method simulated distribution system metal release, using first-order kinetic models, with R2 values of up to 0.98, demonstrating its beneficial use as a cost-effective alternative to otherwise more complicated pipe loop studies.
162

Developing Cost-Effective Specialty Adsorbents to Meet the Emerging Challenges of Pollutant Removal in Surface Water Systems

Ordonez, Diana 01 January 2023 (has links) (PDF)
The production of clean water is emphasized under the United Nations goals for sustainable development (SDGs), enlightening the acute need of developing new sustainable technologies in all disciplines. SDGs have urged all engineers in the 21st century to mitigate pollution of drinking water sources and prevent all receiving waterbodies from the impact of agriculture discharge, wastewater effluent, and stormwater runoff. Current water matrix constituents of concern include traditional pollutants (i.e., total nitrogen and total phosphate), natural organic matters (i.e., total organic carbon (TOC), tannic acid), heavy metals (i.e., copper, calcium), and harmful algae toxins (i.e., microcystin), as well as contaminants of emerging concern (i.e., Per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, endocrine disrupting chemicals, personal care products). This study presents the most recent development of a suite of in situ cost-effective, scalable, and fit-for-purpose specialty adsorbents to simultaneously remove PFAS, TOC, total nitrogen, total phosphate, and microcystin through synergistic effect of different specialty ingredients. It is also aimed to clarify physiochemical removal mechanisms for the removal of color (tannic acid), nutrients (phosphate and nitrate), contaminants of emerging concern (PFAS) and algal toxins (Microcystin LR). The originality of these specialty adsorbents with chemical, molecular, and even microbial insights falls within the sustainable nature of specialty ingredients and wide availability tailored for scalable applications in any landscape.
163

Comparing Hydrogen Peroxide and Sodium Perborate Ultraviolet Advanced Oxidation Processes for 1,4-Dioxane Removal from Wastewater Effluent

Shukla, Tulsi 01 January 2023 (has links) (PDF)
Ultraviolet advanced oxidation processes were compared using sodium perborate (UV/NaBO3 AOP) or hydrogen peroxide (UV/H2O2 AOP) for 1,4-dioxane removal from tertiary wastewater effluent. Both UV/H2O2 and UV/NaBO3 AOPs were also tested with the addition of acetic acid. Results revealed that sodium perborate performed similarly to hydrogen peroxide – the UV/NaBO3 AOP with 6 milligrams per liter (mg/L) as H2O2 resulted in 43.9 percent 1,4-dioxane removal, while an equivalent UV/H2O2 AOP showed 42.8 percent removal. Although the oxidants performed similarly, NaBO3 is an average of 3.3 times more expensive than H2O2. However, the solid form of NaBO3 can provide a major benefit to remote and mobile operations. Unlike H2O2 solution, which degrades over time and requires repeated costly shipments, NaBO3 is a convenient source of H2O2, and a long-term supply can be shipped at once and mixed into solution as needed. Additionally, acetic acid addition increased 1,4-dioxane removal by 5.7 percent in an UV/H2O2 AOP. It is proposed that the UV irradiation of acetic acid produced the acetoxyl radical, which cohesively works with the hydroxyl radical, produced via H2O2 irradiation, to enhance 1,4-dioxane degradation in a combined, novel UV/H2O2/acetic acid AOP. Other UV-AOP observations relate to a decrease of up to 29 percent in total dissolved solids (TDS), an inverse relationship between TDS and turbidity removals, and degradation of organic matter. Despite organic matter changes, the UV/NaBO3 AOP did not reduce trihalomethane formation due to the increased chlorine demand from hydrogen peroxide residual. Additionally, new insights into limitations of H2O2 residual test methods are included.
164

Catch share management in the Northeast multispecies fishery| Implications for the commercial groundfish fishery in New Hampshire

Feeney, Rachel Gallant 29 January 2016 (has links)
<p> This dissertation tests theories about catch share approaches to fishery management, examining their validity and limits relative to the Northeast groundfish sector program, and potentially modifies them in light of research outcomes. Participants of the groundfish fishery based in New Hampshire are the particular focus of research, but broader impacts are considered. Studies of this catch share program have been limited to date, and studies of catch share programs generally have focused on a particular dimension (e.g., biological, social, economic) rather than integrate across dimensions, despite increasing needs to do so for management. Here, six key aspects of fishing are investigated: fishing practices, social capital, bycatch, economic performance, safety, and well-being. Thus, this work is a novel contribution to the field of impact assessment research, both in its topic and scope. </p><p> The primary research question is: <i>How has the advent of catch shares impacted the Northeast commercial multispecies fishery, particularly in New Hampshire?</i> This is answered through a case study that involved a mix of quantitative and qualitative approaches, using semi-structured interviews of 2 informants, including members of groundfish sectors, common pool members, former fishermen, and fish dealers. Although social research often involves a process of theory generation, in the case of the Northeast groundfish fishery, and catch share programs more generally, a number of theories have already emerged that are ripe for testing. It was hypothesized here that fishing under the control rules governing sectors has resulted in: more efficiency and flexibility for fishermen to decide where, when, and how to fish; greater social capital among fishermen; reduced bycatch; and improved economic performance, safety, and well-being. </p><p> The groundfish fishermen of New Hampshire revealed that the theorized benefits of catch share programs do not necessarily hold true. Of the six key aspects of fishing investigated here, only the benefits related to fishing practices, bycatch and safety aligned with what has occurred in this local fishery, but even some of those benefits have qualifiers. The informants who were sector members generally felt that fishing in a sector was more efficient and flexible than the former Days-At-Sea program had been, generally due to shifting catch limits from a trip basis to an annual one. This had allowed more concentration of effort during times with greater potential for profitability (e.g., fish availability, favorable markets). Reducing bycatch was an important goal of the informants, and the sector participants indicated that their level of bycatch had decreased, primarily through eliminating the trip limits and discards of legal-sized fish. Some informants went above and beyond regulations to avoid bycatch in recognition of the need to steward stocks for the future. However, some sector members identified new pressures to discard when unobserved, driven largely by the high lease costs of choke stocks. There were no major changes in safety, because the informants largely strive to be safe no matter the management program. However, removal of trip limits for sector participants created flexibility and less pressure to fish in unsafe conditions. </p><p> Theorized benefits for social capital, economic performance, and well-being did not hold true. Despite being a novel focal point for industry organization, informants felt that sectors have not been catalysts for social capital. Rather, sectors have been based on and built off of pre-existing social capital. In some cases, social capital was reduced as increased organizational responsibilities were seen as a burden and fishing became more competitive and secretive. Economic profitability and predictability had not been realized, though the concomitant decline in, and persistently low, catch limits for certain key species (e.g., cod, yellowtail flounder) vanquished any potential that catch shares had for the economic success of this fishery. The need to lease quota of constraining stocks to harvest the available fish in one&rsquo;s own portfolio has been a substantial and new cost, with risky debt obligations, for several informants. Business predictability declined for a majority of informants. Catch shares has, however, transformed the business climate of the groundfish industry, with more focus on maximizing one&rsquo;s utility. With declines in fishery participation, and dim potential for positive economic performance, the sense of well-being and future outlook for self and fishery had diminished since the advent of the catch share program. Job satisfaction decreased for most of the sector members, and a majority of all informants said that they would not advise a young person to enter fishing. The New Hampshire-based fishermen have, on the whole, not fared as well as could be assumed based on theory, exemplifying the consequences of catch shares, the potential for declining performance by those participants unable to adapt.</p>
165

Community decisions about innovations in water resource management and protection

Houle, James J. 29 January 2016 (has links)
<p> The purpose of this study was to investigate the social, economic and technological factors that influence rates of adoption of innovative stormwater management approaches in municipal organizations in the Great Bay watershed, NH. The scope of this study was to investigate how innovations spread through municipal populations in a specific region and watershed area of the US. The methodology used mixed qualitative methods, including semi-structured interviews, case studies, and surveys to examine perceptions, attitudes, and beliefs that influence the adoption of innovative stormwater management solutions, as well as the governance characteristics of municipalities at different stages of adoption. Major findings include: adopter categories can be relatively easily and quickly categorized into early and late majorities as a preliminary means to identify populations of ready and willing audiences interested in and capable of advancing innovations; early and late adopter classifications followed general diffusion theory, but differed in substantial ways that could influence overall project or program success; and finally that early majority communities have more internal and external capacity to advance innovations as well as higher levels of peer-to-peer trust to offset perceptions related to economic risk that can either advance or stall innovative stormwater management solution adoption. This research offers insights on how to allocate scarce resources to optimally improve water quality through stormwater management solutions, and makes recommendations for how to effectively and efficiently generate greater understanding of complex barriers to adoption that thwart innovation in municipal governance organizations. One significant implication is that agents of change who want to move innovations through a broad municipal population should focus their efforts on working with innovators and early adopters that have status within relevant peer networks and who have capacity to evaluate the strengths and weaknesses of innovations.</p>
166

Enhancing the sustainability through customer relationship management as a solution to the sustainability of the independent short-term insurance broker / Jan Adriaan Oeschger

Oeschger, Jan Adriaan January 2013 (has links)
This study sets out to validate that a Customer Relationship Management system is an enhancing factor in the sustainability of the short-term insurance broker’s business. This objective frolm the fact that very few brokers utilize a complete and integrated Customer Relationship System that could enable them to use the data and information they hold in an effective and sustainable manner. For this reason a primary objective was developed and from this secondary objectives supporting the key issues in Customer Relationship Management systems, sustainability, use ability, interphase, security and integration ability. An empirical study was conducted and a detailed representation of the facts and key issues to the problem statement was analysed. Various detailed analogies were created from which accurate and reliable deductions were derived. A sample population of bona-fide independent short-term brokers in the North-West province of South Africa were compiled by employing strict discriminatory criteria. A questionnaire was developed that tests the key aspects. The questionnaire used key demographic questions, while the component specific questions employed a Likert scale. A total of 75 questionnaires were distributed and 61 were received back that could be used for statistical analysis. Results from the research indicated that the factors contributing to Customer Relationship Management are cost and value enhancing. These factors signify sustainability and that a CRM system can deliver, user interphase, cloud computing, data security and system integration ability. The findings developed in a key conclusion shows that not only is Customer Relationship Management a key factor to sustainability, but it is an emerging factor of Customer Resource Management as well. A secondary finding is that most brokers have some sort of Customer Relationship Management system, but they do not know what they have and how to utilize it to the full. / MBA, North-West University, Potchefstroom Campus, 2014
167

Enhancing the sustainability through customer relationship management as a solution to the sustainability of the independent short-term insurance broker / Jan Adriaan Oeschger

Oeschger, Jan Adriaan January 2013 (has links)
This study sets out to validate that a Customer Relationship Management system is an enhancing factor in the sustainability of the short-term insurance broker’s business. This objective frolm the fact that very few brokers utilize a complete and integrated Customer Relationship System that could enable them to use the data and information they hold in an effective and sustainable manner. For this reason a primary objective was developed and from this secondary objectives supporting the key issues in Customer Relationship Management systems, sustainability, use ability, interphase, security and integration ability. An empirical study was conducted and a detailed representation of the facts and key issues to the problem statement was analysed. Various detailed analogies were created from which accurate and reliable deductions were derived. A sample population of bona-fide independent short-term brokers in the North-West province of South Africa were compiled by employing strict discriminatory criteria. A questionnaire was developed that tests the key aspects. The questionnaire used key demographic questions, while the component specific questions employed a Likert scale. A total of 75 questionnaires were distributed and 61 were received back that could be used for statistical analysis. Results from the research indicated that the factors contributing to Customer Relationship Management are cost and value enhancing. These factors signify sustainability and that a CRM system can deliver, user interphase, cloud computing, data security and system integration ability. The findings developed in a key conclusion shows that not only is Customer Relationship Management a key factor to sustainability, but it is an emerging factor of Customer Resource Management as well. A secondary finding is that most brokers have some sort of Customer Relationship Management system, but they do not know what they have and how to utilize it to the full. / MBA, North-West University, Potchefstroom Campus, 2014
168

The human resources management (HRM) practices a panacea to the challenges of the Minstry for Home Affairs

Gamedze, Sipho Benedict 27 September 2012 (has links)
As the public sector continues to face competitive challenges from the general public, the need for better service delivery and increased productivity has become extremely important. The increased need for optimum service delivery in public sector institutions like the Ministry for Home Affairs has had significant impact on its operations. However, little is known about the challenges faced by the Ministry for Home Affairs regarding the causes of the inefficiency. A range of organizational factors can affect the nature, effectiveness, excellence and novelty of service provision to members of the public.
169

Estimating Seed Bank Responses to Changing Environmental Conditions in the Louisiana Coastal Zone

Horaist, David W. 28 January 2016 (has links)
<p> The coastal zone of Louisiana is changing due to multiple pressures associated with sea-level rise, subsidence, and the inability of sediment or organic accretion to keep pace. The expected increases in sea level and salinity may affect the distribution of the existing plant communities. In addition, these changes in the environment could lead to shifts in plant community composition. During the summer of 2014, I researched how changes in salinity and water levels may change the establishment of vegetation in Louisiana marshes. Randomly selected Coastwide Reference Monitoring System (CRMS) sites were used to collect vegetation data and soil samples. The collected soil samples from fresh, intermediate, brackish, and saline marsh sites were used in a seed bank study. The seed bank study evaluated the effects of different levels of salinity and flooding on seed germination and species richness. Seed germination was highest in soil samples collected from fresh and intermediate sites when these samples were exposed to low salinity (0.0 ppt) and non-flooded conditions. My study only found 43 seedlings in the 10 ppt treatment of 336 total seed germinations, and only 2 seedlings were found in the 20 ppt salinity treatment. Salinity was the dominant factor governing seed germinations and species richness. I also determined that the parent plants for the species found in my seed bank study were more likely to be found within the study site. However, the species data showed at least one species or genus was not present in either the historical or the field collected data. Therefore, the dispersal distance of some seeds from their parental seed provider could have been several hundred meters.</p>
170

Development of gene expression-based biomarkers of exposure to metals and pesticides in the freshwater amphipod Hyalella azteca

Gott, Ryan Christopher 29 June 2016 (has links)
<p>Ecological risk assessment (ERA) is a framework for monitoring risks of exposure and adverse effects of environmental stressors to populations or communities of interest. One tool of ERA is the biomarker, which is a characteristic of an organism that reliably indicates exposure to or effects of a stressor like chemical pollution. Traditional biomarkers which rely on characteristics at the tissue level and higher often detect only acute exposures to stressors. Sensitive molecular biomarkers may detect lower stressor levels than traditional biomarkers, which helps inform risk mitigation and restoration efforts before populations and communities are irreversibly affected. In this study I developed gene expression-based molecular biomarkers of exposure to metals and insecticides in the model toxicological freshwater amphipod Hyalella azteca. My goals were to not only create sensitive molecular biomarkers for these chemicals, but also to show the utility and versatility of H. azteca in molecular studies for toxicology and risk assessment. I sequenced and assembled the H. azteca transcriptome to identify reference and stress-response gene transcripts suitable for expression monitoring. I exposed H. azteca to sub-lethal concentrations of metals (cadmium and copper) and insecticides (DDT, permethrin, and imidacloprid). Reference genes used to create normalization factors were determined for each exposure using the programs BestKeeper, GeNorm, and NormFinder. Both metals increased expression of a nuclear transcription factor (Cnc), an ABC transporter (Mrp4), and a heat shock protein (Hsp90), giving evidence of general metal exposure signature. Cadmium uniquely increased expression of a DNA repair protein (Rad51) and increased Mrp4 expression more than copper (7-fold increase compared to 2-fold increase). Together these may be unique biomarkers distinguishing cadmium and copper exposures. DDT increased expression of Hsp90, Mrp4, and the immune response gene Lgbp. Permethrin increased expression of a cytochrome P450 (Cyp2j2) and decreased expression of the immune response gene Lectin-1. Imidacloprid did not affect gene expression. Unique biomarkers were seen for DDT and permethrin, but the genes studied were not sensitive enough to detect imidacloprid at the levels used here. I demonstrated that gene expression in H. azteca detects specific chemical exposures at sub-lethal concentrations, making expression monitoring using this amphipod a useful and sensitive biomarker for risk assessment of chemical exposure.

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