Dissertations / Theses: 'Environmental potential'

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Arrigo, Leah M. "Phosphinimines as potential technetium environmental sensors." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4694.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 4, 2007) Vita. Includes bibliographical references.

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Ng, Wai-sze. "Educational potential of country parks /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17665322.

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Åsander, Carla. "Perceived Environmental Liability Risks : Potential Implications for the Swedish Environmental Insurance Market." Thesis, Stockholm University, Interdisciplinary Environmental Research (CTM), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7179.

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Syftet med denna uppsats är att undersöka de uppfattade miljöansvarsrisker hos företag som bedriver miljöfarliga verksamheter inom Stockholms län. Dessutom skall jag identifiera potentiella implikationer av dessa uppfattade risker för den svenska miljöförsäkringsmarknaden.

Svensk lagstiftning kräver att företag i Sverige tecknar en ansvarsförsäkring. Ansvarsförsäkringen täcker både första och tredje parts anspråk då en plötslig, oförutsedd händelse har givit upphov till skada, även miljöskador. Gradvisa miljöskador innefattas inte av den svenska ansvarsförsäkringen. Dessutom har företag som bedriver miljöfarliga verksamheter har också krav på sig att avsätta medel till den obligatoriska miljöskade- och saneringsförsäkringen. Den lagstadgade miljöskadeförsäkringen syftar till att kompensera individer som skadats men inte har möjlighet att kompenseras av förorenaren, till exempel om det inte kan påvisas vilken som är ansvarig eller om den förorenande företaget gått i konkurs.

Denna empiriska studie, vilken omfattat intervjuer av företag som bedriver miljöfarliga verksamheter i Stockholms län, har visat att många företag saknar kunskap om vilket miljöförsäkringsskydd som företaget har. De har både bristfälliga insikter i ansvarsförsäkringens villkor samt i de obligatoriska miljöförsäkringarna. I många fall framgick det att företagen tog förgivet att de var den försäkrade parten. Detta är långt ifrån sanningen; för att uppnå ett heltäckande miljöförsäkringsskydd mot både plötsliga, oförutsedda och gradvisa omständigheter, krävs en tilläggsförsäkring (EIL- Environmental Impairment Liability). Utan EIL tar företagen på sig en betydande risk för ekonomiska förluster i samband med gradvisa miljöskador.

Det finns få prejudikat inom miljöjuridik, och särskilt miljöansvar, i Sverige idag. Principen förorenaren betalar (PPP-Polluter Pays Principle) är en viktig del av miljö-lagstiftningen vilken innebär att förorenaren åläggs ansvar för de skador denne har givit upphov till. Men i praktiken har PPP inte implementerats fullt ut vilket har lett till osäkerheter i tolkningen av miljöansvarslagstiftningen samt i hur företag skall hantera miljöansvarsrisker.

EIL försäkring har till följd av detta än så länge varit en sakta ökande marknad för försäkringsbolagen i Sverige. Denna studie pekar mot flera sannolika faktorer som kan ligga bakom den tröga EIL marknaden: 1) företagens ovisshet angående sitt faktiska miljöförsäkringsskydd, 2) förvirringen kring de lagstadgade miljöförsäkringarna och till och med 3) avsaknaden av miljöansvarsprejudikat i Sverige.

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Groode, Tiffany Amber 1979. "Biomass to ethanol : potential production and environmental impacts." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43144.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.
Includes bibliographical references.
This study models and assesses the current and future fossil fuel consumption and greenhouse gas impacts of ethanol produced from three feedstocks; corn grain, corn stover, and switchgrass. A life-cycle assessment approach with an integrated Monte Carlo uncertainty analysis is applied to each of these three bioethanol pathways. Incorporating a Monte Carlo uncertainty analysis within a life-cycle model enables one to account for system variability within the agricultural, technological, and geographic arenas. This results in a range of energy and greenhouse gas impacts rather than previous single-valued estimates. This uncertainty analysis brings greater clarity to the ethanol debate through evaluating the probability of previously published life-cycle assessment net energy results, from reports such as Farrell, Wang, Shapouri, and Pimentel. Lifecycle assessment net energy results show corn grain ethanol to have a positive value when DDGS coproducts are included within the assessment boundary and a slightly negative value when they are not. The system net energy value and GHG emissions are also sensitive to system input assumptions and geographic location. For lignocellulosic ethanol produced from corn stover and switchgrass, a positive net energy value and reduced GHG emissions are seen when compared to gasoline. In addition to net energy results and system GHG emissions, the petroleum displacement and land use impacts for an expanding and evolving ethanol industry are also evaluated.Corn grain, corn stover, and switchgrass-based ethanol potential production levels are also analyzed. It was determined that 55-65 billion liters per year of corn grain ethanol could potentially be produced in the next 10 years, consuming 30% of future US corn grain production. Corn stover and switchgrass have the potential to produce 25-35 and 10-20 billion liters per year of ethanol, respectively.
(cont) These ethanol production results were then applied to assess the feasibility and environmental impact of achieving the new Renewable Fuels Standard, of producing 136 billion liters of renewable fuels by 2022. This study concluded that while the scale is potentially feasible from these three feedstocks, the timeline to achieve this scale would be very challenging given the cellulosic ethanol technological and economic advances that are still needed.
by Tiffany A. Groode.
Ph.D.

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Wilkes, Luanne. "Potential environmental enrichment for zebrafish used in regulatory toxicology." Thesis, University of Exeter, 2011. http://hdl.handle.net/10036/3456.

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The aim of environmental enrichment is to alter the environment of a captive animal in a way that results in improved mental and physical welfare. The technique has been utilised effectively for many years for captive mammals in a variety of settings. However, until now it has never been considered as a way of improving the welfare of aquatic animals such as fish. Fish that are used in regulatory toxicology studies are at present maintained solely in barren tank environments. Little is known about how these types of environments affect the well-being of the animals residing there and whether they impact either physiological heath or behavioural repertoire. This thesis aims to address this gap in the knowledge regarding the potential for environmental enrichment to improve the welfare of fish used in regulatory toxicology. More specifically it looks at two types of enrichment and the effects of these on the commonly used model species, the zebrafish (Danio rerio). The first type of enrichment studied was glass rod structures of varying heights provided to increase tank complexity and provide refuge. The glass structures did not produce any quantifiable benefits in unstressed fish and appeared to delay the formation of stable social hierarchies. When fish were stressed by a period of chasing, the presence of the glass rods appeared to reduce the magnitude of the cortisol response. Whilst this could be viewed as a potential benefit, it was felt that it would not outweigh the costs of this type of enrichment. The second type of enrichment studied was provision of airstones. Again, no clear evidence was found that fish in tanks with airstones experienced an improvement in welfare. The main observation was the vast increase in mortality in tanks containing these airstones, in particular, those of a smaller size. Regardless of the physiological cause underlying this result, this can only be viewed as a negative consequence and one that appears to rule out airstones as an effective form of enrichment for this species and strain of fish. It was also observed that both stress and the presence of enrichment influenced the absolute deviation from the mean in several endpoints. Since changes in endpoint variation will have effects both on the number of animals required to statistically measure environmentally relevant effects this is a factor that should be considered when researching methods of environmental enrichment. Finally, results from these studies suggest the possibility that laboratory zebrafish do not require the addition of environmental enrichment to tanks in order to promote maximum welfare. Furthermore, as considerable costs would be involved in implementing many types of enrichment (relating to manufacture, cleaning, incompatibility of results with previous studies etc.) it is likely that observed benefits would have to be both substantial and well established in order for changes in regulatory guidelines to take place. For a species such as zebrafish that are extremely easy to breed and maintain in the laboratory with minimal amounts of disease, social problems or mortalities, it may be that current conditions are satisfactory.

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Chan, Sai Yen Victor, and 陳世欽. "Potential environmental hazards of wastewater from hospitals and theirmitigation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B41016257.

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Yoko, Zebadiah Gaze. "Evolution of Intraspecific Genetic Differences Across Heterogeneous Environments and the Potential Impacts on Environmental Restoration." Thesis, North Dakota State University, 2020. https://hdl.handle.net/10365/31737.

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Genetic differences evolve between seed sources of widely distributed species that can impact restoration success. Using the herbaceous perennial Geum triflorum (Pursh) as a model species, we examine genetic differences that evolve across a species’ range in both physiology and fitness. G. triflorum occurs across highly differentiated environments consisting of prairie and alvar habitats. Seeds were collected from 22 populations across three eco-geographic regions. Through a common garden experiment in the prairie environment, I first examined differences in physiological traits between source regions and populations. Significant regional differentiation was observed for a majority of traits assessed, with equal or greater trait variation observed at the population scale. Secondly, differences in fitness between source regions were assessed over a period of three years using the ASTER model. Despite being in the home environment, fitness was considerably lower in prairie-sourced plants than alvar sourced plants, both each year and in total.

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Lanza, G. R., and Phillip R. Scheuerman. "In Situ Bioremediation Potential at Cresote Contaminated Sites." Digital Commons @ East Tennessee State University, 1992. https://dc.etsu.edu/etsu-works/2893.

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Scheuerman, Phillip R. "In Situ Bioremediation Potential at Creosote Contaminated Sites." Digital Commons @ East Tennessee State University, 1992. https://dc.etsu.edu/etsu-works/2960.

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Wei, Wei S. M. Massachusetts Institute of Technology Department of Civil and Environmental Engineering. "Vehicle activity patterns and electrification potential." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111418.

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Thesis: S.M. in Transportation, Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 69-73).
Battery electric vehicles (BEVs) are among the most promising solutions to transportation decarbonization, yet some vehicle-days' energy requirements cannot be satisfied by an existing, affordable BEV. These days account for a significant percentage of total personal vehicle energy consumption in the United States (US). Identifying activity patterns on these high-energy days is important for estimating the potential for mass adoption of BEVs. However, the current literature has yet to understand the characteristics of such days at the national level, and the implications for the electrification potential of personal vehicles. This thesis aims to understand what kinds of vehicle activity patterns constitute highenergy vehicle-days and to evaluate potential solutions for vehicle electrification, namely improving BEV charging infrastructure and car-sharing. We have developed a set of methods to extract representative high-energy vehicle-day activity profiles. Targeting such days, the thesis evaluates the increase in BEV adoption potential through expanded charging infrastructure, providing commercial car-sharing, and allowing intra-household vehicle-sharing. This research finds that high-energy days across the US have relatively regular vehicleday activity patterns. Car-sharing and expanded charging infrastructure an help enable BEV adoption potential. On a typical day, providing commercial car-sharing services for the longest home-based tour to 9% of vehicle-days is equivalent to increasing everyones' battery capacity level by 17%, in terms of BEV adoption potential. Furthermore, intrahousehold vehicle-sharing shows promise for increasing BEV adoption potential. Methods and insights from this research can help decision-makers identify efficient policy options for accelerating BEV adoption.
by Wei Wei.
S.M. in Transportation

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Vichabian, Yervant. "An environment application of self-potential geophysics." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/46086.

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Lewis, G., and Phillip R. Scheuerman. "Bioremediation Potential of Creosote Constituents Using Constructed Wetlands." Digital Commons @ East Tennessee State University, 1993. https://dc.etsu.edu/etsu-works/2895.

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Pensulo, Chibesa. "THE POTENTIAL OF BIOCHAR TO ENHANCE ENVIRONMENTAL SUSTAINABILITY IN SWEDEN." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-167675.

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Environmental sustainability in Sweden is challenged by rising greenhouse gas emissions from transportation, input-intensive agriculture and potentially unsustainable removal of organic material from forests and farmland. The Swedish government is working towards sixteen environmental quality objectives in order to overcome these problems, among others. The past decade gave rise to an international research community dedicated to investigate the age-old practice of applying charcoal to soil, practiced most notably by ancient civilisations in the Amazon region of South America. The high level of interest and controversy around this subject inspired this investigation of biochar’s potential benefits in Sweden. A scientific study was conducted to examine the potential of biochar to enhance environmental sustainability in Sweden. This was largely a desk study, supplemented by expert interviews, GIS map work, an experiment and mathematical analysis. It was found that there was insufficient research to date to prove the agronomic benefits of biochar in Sweden. More field studies are required to build up the evidence of its potential. Furthermore, as the rate of mineralization of the carbon content is dependent on numerous factors, including the composition of the soil to which the biochar is applied, it is difficult to conclusively define biochar’s carbon storage potential. This study adds to the existing body of knowledge on the subject by integrating the conclusions from a variety of studies and expert opinions, as well as by providing maps indicating land areas in Sweden that would be likely to benefit from biochar application.

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Chan, S. Y. "Potential environmental hazards of wastewater from hospitals and their mitigation /." View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B34739336.

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Chang, Huei-Chun, and huei-chun chang@rmit edu au. "Environmental Management Accounting within Universities: Current State and Future Potential." RMIT University. Accounting and Law, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080424.122823.

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Environmental management accounting (EMA) is attracting increased recognition as a management tool that assists in improving financial and environmental performance through enhanced environmental accountability. Various industries have been included in EMA-related research and study, but universities have typically failed to be the focus of the attention. This research studied the experiences of key managers from five universities to explore potential factors influencing the decision to adopt, or not to adopt, EMA within the higher education sector. For the purpose of this study, EMA is defined as the generation, analysis, and use of monetary (or financial) and physical (or non-financial) environment-related information in order to improve organisational financial and environmental performance. The two objectives of this study were to understand current accounting practices for managing major environmental costs, and to identify factors influencing EMA adoption within universities. For the purpose of this study, the major environmental costs referred to are limited to the costs pertaining to the consumption of electricity, water and paper, and the generation of wastes. A case study methodology was followed using semi-structured interviews of key personnel with four different management functions (i.e. environmental management, management accounting, senior management, and heads of academic schools) within each university, and performing content analysis on the transcribed interview data. Specifically for achieving the second research objective, a theoretical framework that considers four theories was embraced to guide the data collection and focus the study. The four theories are contingency theory, institutional theory, legitimacy theory, and stakeholder theory. The findings of the first research objective revealed that there was a general lack of EMA utilisation within the case universities. This was in part due to a perceived lack of appreciation by key personnel of the extent of environmental costs being incurred, but arguably mainly because of the absence of relevant environmental cost information being brought to the attention of senior management. Although environmental sustainability was promoted as important from an environmental management perspective, efforts to improve internal environmental accountability, in particular from an accounting perspective, were still absent. In relation to the second research objective, it was found that five key barriers contributed to this lack of EMA utilisation within the five case universities, and they were attitudinal, financial, informational, institutional, and management barriers. Among the factors that provide further explanations about how each barrier influences EMA adoption, resistance to change, resource constraints, (a lack of) legitimacy considerations, and a lack of environmental responsibility & accountability were found to be strong factors, as they were supported in all of the five cases. Apart from the theoretical extension to this area of research, the results and findings of this study supported the uses and applications of EMA by the higher education sector. Much more can, and should, be done by universities in relation to how they account for the environment. This can provide benefits not only for the sector itself, but also for the environment in which we live.

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Chan, Sai Yen Victor. "Potential environmental hazards of wastewater from hospitals and their mitigation." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B41016257.

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Koutsoumpeli, Eleni. "Exploring the potential of antibody mimetics for detecting environmental contaminants." Thesis, University of York, 2017. http://etheses.whiterose.ac.uk/18473/.

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Over the past 15-20 years, there has been growing interest and concern from the scientific and regulatory communities over the potential risks of emerging environmental contaminants (ECs). State-of-the-art techniques used for monitoring ECs do not provide the high spatial and temporal resolution measurements required to better understand and mitigate the risks. Immunoassays, which use antibodies to detect a target compound with high affinity, specificity and selectivity, partly address these limitations. However, the use of antibodies for the detection of small-sized, non-immunogenic environmental contaminants, presents a number of challenges. Recent advances in protein engineering have led to the emergence of antibody mimetics that offer the high affinity and specificity associated with antibodies, but with reduced batch-to-batch variability, increased stability, and in vitro selection to ensure rapid discovery of binders against a wide range of targets. This study explores the potential of Affimers, a recent example of antibody mimetics, as suitable bioreceptors for the detection of small organic molecules. Methylene blue (MB), a redox-active molecule used as a fabric dye and diclofenac (DCF), an important environmental contaminant, were selected as the target compounds and Affimers against MB and DCF were developed by the BioScreening Technology Group, University of Leeds. The objectives of this project were to a) demonstrate that the developed Affimers can bind to the selected targets with very high affinity, b) assess their performance in the complexity of environmental water samples (selectivity), and c) investigate the potential of an Affimer-based assay for small molecule detection. Target immobilisation for Affimer characterisation was achieved using long-chained alkanethiol linkers coupled with oligoethylene glycol (LCAT–OEG) and the immobilisation approach was evaluated through electrochemical measurements and infrared spectroscopy. Subsequently, binding between the immobilised targets and target-specific Affimers was quantified using quartz crystal microbalance with dissipation monitoring (QCM-D). Affimer affinity studies revealed Affimer dissociation constants (KD=13.7 nM and 73 nm for MB and DCF Affimers respectively) was comparable to that of high affinity antibodies. Furthermore, the high selectivity of MB-Affimers was demonstrated using limnetic water samples. Finally, an Affimer-based competition ELISA was demonstrated (LOD=75 nM), illustrating the potential of Affimers as bioreceptors in immunoassays for the detection of small-sized, non-immunogenic compounds. These findings are very promising, encouraging further research into Affimer-based assays and biosensors in order to introduce a novel, alternative path for rapid, on-site monitoring of contaminants in the environment.

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Boiridy, Mia Ingrid. "Potential chemical remediation of mercury in recently impounded reservoirs." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27286.

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Several mitigation procedures have been proposed to limit the transfer of Hg and MeHg to aquatic organisms but most cannot be applied to large reservoirs such as those of northern Quebec for practical, economical, and environmental reasons. A better understanding of the diagenetic behaviour of Hg and methylmercury in aquatic environments has lead us to consider methods of enhancing natural processes which would either limit the mobility of Hg in flooded soils or its methylation. Different concentrations of iron oxide, iron shavings and ferrous ammonium sulphate were added to soil slurries in the presence or absence of calcite and gypsum. Mercury released to the supenatent solutions and methylmercury adsorbed to the slurry solids were monitored with time to determine the trapping efficiency of the different chemical additives under both reducing and oxygenated conditions. Whereas all three reagents limited the release of Hg(2+) to the supernatent solution when reducing conditions were allowed to develop in the slurries, ferrous ammonium sulphate appeared to be the most effective at limiting Hg methylation. (Abstract shortened by UMI.)

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Dietlin, Philipp 1979. "The potential for low-cost airlines in Asia." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28301.

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Thesis (S.M. in Transportation)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.
Includes bibliographical references (p. 123).
The purpose of this thesis is to assess the potential for low-cost airlines in Asia. Low-cost airlines have been very successful in North America and Europe and have significantly impacted the airline industry and its stakeholders. In what ways and to what extent this might be repeatable in Asia is the underlying question of this thesis. An investigation of the low-cost airline business model reveals that there are a number of key elements that make it so successful on both sides of the Atlantic. But what works in North America and Europe may not be feasible in Asia. An analysis of the Asian airline industry shows that it differs from the rest of the world in several important dimensions, which will substantially affect prospective low-cost airlines. On the one hand, the rigid regulatory frameworks in most parts of Asia and the fact that many traditional Asian airlines have some of the world's lowest unit costs may not allow Asian low-cost airlines to thrive in the same way as they have in other parts of the world. On the other hand, a breakdown of Asia's socioeconomic indicators shows that the continent is bound to experience significant growth in intra-Asia air travel over the coming years. The low-cost airline business in Asia is therefore challenging in several ways but potentially very lucrative. The possible impacts that an increasing presence of low-cost airlines in Asia would have on the various stakeholders in the region are substantial. While some of these stakeholders will likely benefit from a growing presence of low-cost airlines in Asia, others might have a lot to lose. This thesis analyses several stakeholder groups and suggests potential response options.
by Philipp Dietlin.
S.M.in Transportation

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Kumar, Harjinder. "Laboratory evaluation of electric arc furnace slag as a potential wetland substrate." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18690.

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Phosphorus (P) is considered as the controlling element in the proliferation of eutrophication in water bodies. Constructed wetlands are accepted as the most appropriate treatment technology for removal of nutrients, including phosphorus from agricultural drainage waters. As most of P removal in constructed wetlands is through precipitation and abiotic sorption, introduction of suitable substrate can enhance the P removal efficiency of the system. Slag has immense capacity for P sorption however its composition and ability as a wetland substrate varies from locale to locale. A study divided into bench and pilot scale was undertaken to evaluate the efficiency of a locally available electric arc furnace slag (EAFS). The pilot scale study was used to validate the findings of bench scale together with conducting additional investigations. In bench scale study EAFS was found to have high efficiency (nearly 100%) in P removal. Amount of P removed increased by increasing the contact time between the P solution and the slag. Where mechanical shaking appreciably enhanced the P-removal efficiency (90 %) in 3 hour, aeration resulted in (97-99%) phosphorus removal in a much reduced contact time of one hour for all P concentrations used (0.3, 3.0, 6.0 mg/L). Adsorption capacity of 1457 mg/kg was ascertained for this slag. In the pilot scale study higher P removal was recorded in residence time treatments of five and ten hour but, the rate of removal was slower than what was observed in case of one and two hour residence time. The EAFS when subjected to application of a high concentration of P solution over 72 hour period depicted a gradual decrease in the P removal efficiency, falling from 85% to 53% at the end of experiment. It was also established that EAFS can be regenerated to 70% of its original P-sorption capacity by putting it to a resting period of 3 weeks.
Le phosphore est considéré comme l'élément nutritif déterminant dans le foisonnement par eutrophisation des eaux. Les marais artificiels sont reconnus comme la technologie la plus appropriée pour enlever les éléments nutritifs, tel le phosphore, des eaux usées agricoles. Comme la majorité de l'enlèvement du P dans les marais artificiels est le résultat de précipitation et de sorption abiotique, l'introduction d'un matériel approprié pourrait améliorer l'efficacité d'enlèvement de P du système. Quoi que les scories ait une immense capacité de sorption du P, leur composition et applicabilité comme matériel de marais filtrant varie toutefois de lieu en lieu. Une étude visant à évaluer l'efficacité de scories de four électrique à arc (SFEA), disponibles localement, à ces fins, fut entreprise à l'échelle de banc d'essai, ainsi qu'à l'échelle préindustrielle. A cette dernière échelle l'étude servit à valider les résultats de l'étude à l'échelle de banc d'essai, ainsi qu'a compléter d'autres expériences. A l'échelle du banc d'essai, la SFEA montra un efficacité d'enlèvement du P très élevée (près de 100%). La quantité de P enlevée augmenta de concert avec la durée de contact entre la solution contenant le P et les scories. Pour toutes les concentrations de P étudiés (0.3, 3.0, et 6.0 mg/L), une agitation mécanique améliora notamment l'efficacité d'enlèvement du P (90% en 3 hr), tandis que l'introduction d'une aération eu pour résultat un enlèvement quasi-total (97-99%) du P dans un temps de contact beaucoup plus court (1 hr). Une capacité d'adsorption de 1400 mg/kg fut déterminé pour ces scories. Lors de l'étude à l'échelle préindustrielle, des temps de séjour plus longs (5 et 10 h) augmentèrent l'enlèvement du P, mais le taux d'augmentation de l'enlèvement du P fut significativement plus élevé lors des premières (1, 2 h) heures de séjour. Lorsque soumises à une application d'une solution

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Wilde, Christian. "Algae carbon uptake and oxygen production potential at high carbon dioxide concentrations." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104887.

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As evidence piles up indicating that anthropogenic CO₂ emissions are affecting the world's climate with potentially devastating results for its population, more attention is being directed towards means to reduce the quantities of CO₂ being released. The production of energy through the burning of fossil fuels is the primary cause of these emissions, but is also vital to our current lifestyle and even survival. As such, it is essential that we develop reliable and economically viable renewable fuels to ensure that we have the energy needed to sustain our society into the future. To this end, it has been proposed that industrial flue gas containing large amounts of CO2 could be treated using algae. The algae would consume the carbon to grow, and could then be harvested to produce carbon neutral biofuels. Through photosynthesis, algae also produce oxygen as a by-product when growing. In the industrial algae carbon capture processes typically envisioned, this oxygen is produced in low concentrations and so is vented to the atmosphere as a waste product.In this study, we propose two scenarios in which an algae photobioreactor system could be developed to produce a valuable supply of oxygen enriched air, or even pure oxygen. Recovering and making use of this typically overlooked by-product has the potential to make industrial carbon capture and biofuel production more economically viable, and also has added environmental benefits. The key issue to consider for these proposed oxygen production systems is whether the algae themselves are capable of surviving, and more importantly growing, under the conditions they will be subjected to. The CO₂ and oxygen concentrations found within these systems would be drastically higher than those of ambient air. We demonstrate that both these proposed oxygen production processes are in fact feasible. Further, that with the setup we designed, high concentrations of oxygen and CO₂ may have a slight hindering effect on algae growth rates, but that neither completely inhibits growth. In addition, the oxygen production potential of three different algal species (Anabaena sp., Synechococcus sp., and Chlamydomonas reinhardtii) was found to be almost identical, suggesting that our proposed systems may be compatible with many different species of algae.
Il devient de plus en plus évident que les émissions anthropiques de CO₂ ont une influence sur le climat de notre planète et que les conséquences pourraient en êtres dévastateurs pour la population. La production d'énergie par la combustion de combustibles fossiles est la cause principale de ces émissions, mais elle est aussi essentielle à notre mode de vie et même, notre survie. Il est donc nécessaire que nous développions des carburants renouvelables qui sont aussi économiquement viables pour assurer que nous avons l'énergie nécessaire pour soutenir notre société dans l'avenir. À cette fin, il a été proposé que les effluents des industries contenant de grandes quantités de CO₂ pourraient êtres traités en utilisant des algues. Elles consumeraient le carbone et ensuite pourraient êtres récoltées pour produire des biocarburants. Grâce à la photosynthèse, les algues produisent également de l'oxygène comme sous-produit. Dans la culture d'algues généralement envisagé, cet oxygène est produit en faible concentration et est donc rejeté dans l'atmosphère, ayant aucun usage industriel.Dans cette étude, nous proposons deux scénarios dans lesquels un système photobioréacteur d'algues pourrait êtres développés pour générer un produit précieux de l'air enrichi en oxygène, ou de l'oxygène pur. La récupération de ce produit habituellement négligé a le potentiel de faire la capture du carbone et la production de biocarburants plus économiquement viables. Pour savoir si un tel système est réalisable, il est important de savoir si les algues sont capables de survivre dans les conditions présentes dans les systèmes. Les concentrations de CO₂ et de l'oxygène dans ces systèmes proposés seraient considérablement plus élevées que ceux de l'air ambiant. Nous démontrons que ces deux processus proposés pour la production d'oxygène sont en fait réalisables. En plus de cela, les fortes concentrations d'oxygène et de CO₂ peuvent avoir un léger effet négatif sur les taux de croissances des algues, mais que leurs croissances ne sont pas complètement empêchées. Finalement, nous démontrons que le potentiel de production d'oxygène de trois différentes espèces d'algues (Anabaena sp., Synechococcus sp., et Chlamydomonas reinhardtii) est à peu près identique, ce qui suggère que les systèmes que nous avons proposé peuvent être compatibles avec de nombreuses espèces d'algues.

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Morgan, M., Phillip R. Scheuerman, C. Bishop, and Rebecca A. Pyles. "The Teratogenic Potential of Atrazine and 2,4-D Using FETAX." Digital Commons @ East Tennessee State University, 1994. https://dc.etsu.edu/etsu-works/2900.

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23

Wu, Bernhard Shiaoyuen. "Environmental stress-induced thermoprotection of action potential signalling in Locusta migratoria." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ63472.pdf.

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24

Krauss, Fabian. "The Potential of Voluntary Environmental Initiatives for Firms in Developing Countries." St. Gallen, 2008. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/01651785004/$FILE/01651785004.pdf.

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25

Jenkins, David. "Potential for the use of light pipes and their environmental implications." Thesis, Edinburgh Napier University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400865.

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Reed, Daniel L. "Environmental and renewable energy innovation potential among the states : state rankings /." View online version, 2009. http://ecommons.txstate.edu/arp/291.

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Kumar, Chitra M. 1977. "GIS methods for screening potential environmental justice areas in New England." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/68384.

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Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2002.
Includes bibliographical references (leaves 81-85).
Over the past decade scholars, scientists, and community advocates have argued that minority and low-income communities have been exposed to disproportionate amounts of hazardous pollution as a result of systematic biases in policy making and discriminatory market forces. Geographic Information Systems (GIS) is an important tool used to assist regulatory agencies in identifying these potentially vulnerable or "potential environmental justice" areas so that programmatic decision-making can incorporate EJ concerns. Yet, few studies have documented or evaluated methodologies for EJ-GIS analyses utilized by public agencies. This paper explores various methodologies that approximate where communities at risk of disproportionate burden may be with respect to the unique character and composition of New England. Specific variables explored are race/ethnicity, poverty, and population density. For each variable a scale and threshold/reference value is determined; also, the possibility of establishing a ranking system was contemplated. The importance of investigating spatial clustering and integrating variables into combined criteria was also discussed. This research began with the problem being framed. Then, a survey of the literature and public institutions was done to identify relevant practices and state-of-the-art technology in environmental justice analysis. Next, a process was designed to develop and select an appropriate methodology. This process included meeting systematically with members of the U.S. Environmental Protection Agency New England GIS team and Mapping Workgroup of the Environmental Justice Council to discuss and compare various methods of analysis. Based on research results, recommendations were made to the EPA New England regional office on how to improve their demographic mapping system. These recommendations are hoped to be adopted by EPA New England and introduced in a desktop GIS tool by the end of 2002.
by Chitra M. Kumar.
M.C.P.

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28

Moyo, Annah. "Characterizing the potential environmental risks of South African coal processing wastes." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29832.

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The environmental impacts of coal processing wastes are a challenge in South Africa as large amounts of coal wastes are produced annually, pegged at 60 million tons per year according to Eberhard (2011). Whilst the fossil fuel-based industry is in decline globally, coal is likely to remain the dominant source of power in South Africa. The major environmental impacts reported in several studies are water pollution and soil quality degradation due to acid rock drainage (ARD) and its associated elevated levels of elements and salts. Several studies have shown the environmental performance of the wastes to be dependent on the geochemical properties of the wastes. Owing to the complex nature of coal wastes, their characterisation using tools developed for hard rock ores is associated with inconsistency and uncertainty. As a result, the South African coal processing wastes are poorly characterized and the associated risks not well understood. This study investigates the reliability of relevant characterisation techniques and interpretation of characterisation data in terms of the environmental risk potential of coal wastes. The outcomes of the study address some of the uncertainties and deficiencies arising from the current characterisation tools and evaluate potential environmental risks posed by coal processing wastes. Laboratory-scale characterisation of the physio-chemical properties and of ARD and elemental risk potential of two ultrafine coal waste and one discard waste sample were conducted. Evaluation of accuracy and repeatability of selected analyses was conducted on a certified coal standard. The selected analyses tested for accuracy and repeatability were total sulphur analysis by Leco and Eschka methods in addition to elemental analysis by wavelength dispersive x-ray fluorescence (WDXRF), inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The ISO 157:1996 and ACARP C15034 protocols for assessment of sulphur forms were also compared and evaluated for precision using the coal standard and coal waste samples. Conversions of the sulphur species under static ARD tests were also studied to understand the sulphur species behaviour and implication on ARD potential. The mineralogy of the coal wastes was evaluated from a quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN) and quantitative x-ray diffraction (QXRD) analysis. In addition, conventional net acid generating (NAG) and acid-base accounting (ABA) static tests were enhanced through extended boil NAG tests to assess the organic acids effect on the NAG capacity. The static tests were validated by theoretical ARD calculated from mineralogy as well as biokinetic shake flask tests which gave the timerelated acid generating behaviour of the coal waste samples. Sequential chemical extractions combined with a simple score and ranking protocol were subsequently used to evaluate the potential water and soil-related risks associated with environmentally available elements and salts in the coal wastes. The results showed both the Leco and Eschka methods to be highly precise (±0.01-0.03 % standard error) but the Leco was more accurate (±3.1 % compared to ±12.5 % relative standard error (RSE)). The total sulphur content of the coal processing waste was less than 2 %. The ISO157:1996 and ACARP C15034 protocols gave comparable and slightly different results but the latter was more precise in sulphate analysis. Furthermore, the ACARP protocol could differentiate the acid forming sulphates from the soluble sulphates giving a better theoretical maximum acid producing potential. The sulphur species from the two chemical methods and QEMSCAN mineralogy showed 52-61 %, 12-26 % and 21-43 % to be sulphide, sulphate and organic/low-risk sulphur respectively. The conversion of the sulphur species showed that partial solubilisation of sulphides in ANC and partial conversion of organic/low-risk sulphur under NAG tests can cause an over or underestimation of ARD potential. The static ARD tests has shown the Witbank coal discards sample to be potentially acid forming (PAF) (9.2-25.9 kg H2SO4/Ton), Waterberg coal slurry to be non-acid forming (NAF) (-68.6 to -46.8 kg H2SO4/Ton) and Witbank coal slurry to be uncertain (-12.1 to 9.9 kg H2SO4/Ton). The extended boil NAG tests showed organic acids effect on the Witbank coal slurry likely caused an overestimation of the NAG capacity. Validation of the static tests by biokinetic tests and ARD calculated from mineralogy classified both Witbank samples as PAF and the Waterberg sample as NAF. The results also showed the net acid producing potential of the coal wastes to depend on the mineralogy of the samples. The elemental results showed WDXRF and LA-ICP-MS analysed most of the elements accurately within ±10 % RSE and that a combination of techniques provides more reliable and accurate results. The analyses showed the coal waste to contain significant amounts of environmentally sensitive elements like Cr, As, Mo, Sb, Se. The ranking and scoring of potentially available elements under oxidising leach conditions evaluated Fe in Waterberg coal slurry and Witbank coal discards to pose high risk in drinking water while S (as sulphate), Pb, Sb, Mn, As, Al and Hg in the three samples pose moderate risk. This case study evaluated the accuracy and precision of commonly used analytical techniques and applicability of risk evaluation protocols for coal processing wastes. The research outcomes underlined some factors that cause uncertainty and inconsistency with the evaluation of ARD potential of coal wastes. The findings highlighted the need to validate and complement the characterisation data using various tools and risk evaluation protocols to overcome specific limitations. The results also indicated the coal wastes have the potential to cause environmental impacts from ARD and elevated concentration of elements and salts, thus providing a basis for designing and implementing waste management strategies which minimise these risks. The mineralogy and elemental composition of coal wastes showed enrichment of elements and presence of potentially usable and economically valuable constituencies for future studies on value recovery. Characterisation of coal processing wastes for air pollution impacts is recommended for future studies as well as a study of ARD behaviour under continuous flow systems to more closely represent the conditions in dump disposal scenario.

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Dobbs, Jonathan. "The Potential Use of PEI Modified Biochar for Different Environmental Applications." Thesis, Mississippi State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10616945.

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Man-made pollution is hazardous to both the environment and human health. This study attempts to develop a low-cost, biobased adsorbent for CO₂ capture and heavy metal removal. The adsorption behavior of CO₂ from air and Pb (II) from aqueous systems onto polyethylenimine (PEI) modified biochar was studied. Chemical and physical pretreatments were performed in an attempt to enhance the adsorption kinetics of biochar. FT-IR and Elemental Analysis were performed to confirm the loading of PEI onto the surface of biochar was achieved. The efficiency of the PEI modified biochar on the removal of Pb (II) from aqueous solutions was determined by Atomic Absorption Spectrometer (AAS). Alkali pretreatment of PEI modified biochar increased CO₂ capture and removal of Pb(II). This experiment introduces a new approach to air and water purification by using the combination of an amine with biochar.

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Ng, Wai-sze, and 吳慧思. "Educational potential of country parks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31253519.

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31

Chen, Emily 1976. "Investigation of potential groundwater intrusion into the Plainville landfill." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80580.

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Inagawa, Hisashi. "Potential of strategic information systems for Japanese construction firms." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/45726.

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Bewley, Stefan K. 1978. "The potential market applications of distributed generation of electricity." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/84317.

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Alsenbel, Amira Moayad. "Investigating Potential Pollutant Sources Causing Lack of Biodiversity in Lytle Creek and Indian Run." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1503743158775888.

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35

Wang, Wenfei. "Houseflies as Potential Vectors for Antibiotic Resistant Bacteria." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1376778563.

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36

Rodgers, Charner Lynn. "High occupancy toll lanes ignoring the potential for a environmental justice violation." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39615.

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In the US transportation system, environmental justice (EJ) issues are regulated by a variety of laws to ensure that all have fair treatment with respect to implementation of policies. If State Departments of Transportation adhere to all regulations properly but unconsciously, then an underlying negative impact on a community may still exist as a result of a newly implemented project. Since the implementation of High Occupancy Toll (HOT) lanes are fairly new, and since there have been numerous concerns from the public about their discriminatory nature, a decision support system is needed to identify potential EJ violations and issues when implementing a new or converted HOT lane. No prior model exists. The goal of this research is to assist state's Department of Transportation (DOT) in the early stages of the development of an HOT lane by developing a Potential Environmental Justice Violation Model that will help state agencies predict potential EJ violations before additional resources are invested into a project. By developing a model, this study identifies and classifies characteristic drivers of potential EJ violations related to communities' economic, social, or health and safety status. The Potential Environmental Justice Violation Model (PEJVM) allows state DOTs employees to define and evaluate the distribution of impacts in the relevant categories. The model provides a method for transforming complex qualitative and quantitative data about a project into a user-friendly format where the results can then be visualized using a spider radar diagram to determine the level of impact of each identified variable. The PEJVM was validated using two previous anonymous HOT case studies and demonstrated using the Interstate 85 Case Study in Atlanta, Georgia. This model offers a uniform method of identifying potential environmental justice violations when implementing a HOT lane. The model will also help inform state agencies of potential violations early in the planning stages of HOT lane projects so that the agency can solve any potential EJ issues before additional resources are invested.

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Degen, Marcia J. "Evaluation of the potential environmental toxic effects of a nylon fibers additive." Thesis, This resource online, 1985. http://scholar.lib.vt.edu/theses/available/etd-03302010-020601/.

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38

Zhu, Rui. "Human-environmental interaction| Potential use of pupil size for office lighting controls." Thesis, University of Southern California, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1568897.

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The goal of this research is to establish a visual environment diagnostic model based on the occupant's physiological responses for detecting improper ambient lighting conditions, a major contributing factor to visual stress and work productivity in office workplace environments. The human body, as a biological mechanism, naturally minimizes the effects of ambient environmental stressors using its physiological autonomous nerve system. This system enables a human's pupils to dilate and contract, depending on visual sensations affected by the ambient lighting conditions. An extensive experiment using human subjects will be conducted in an environmental chamber on the University of Southern California campus. All parametric data including human pupil sizes and lighting parameters will be categorized by age and ethnic origin, to investigate and determine the most common features of pupil sizes per visual sensation among individuals. Lighting parameters, including illuminance (lux), luminance (cd/m2), and lighting-color-temperature (K), will be controlled and maintained for each volunteer subject based on his/her task-type (computer-based or paper-based), which is most typical in the current office environment.

This study will provide unique knowledge concerning how an occupant via his/her physiological signal, i.e. pupil size can interact with the visual (lighting) environment. The research outcome will be potentially applicable in reality to diagnose the lighting quality in workplace environments, and to integrate an occupant's pupil size information for the visual environmental controls.

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Konasinghe, Dheemathee Kokilani Lankathilake. "Mitigating North-South participation inequalities in global environmental governance : potential NGO contributions." Thesis, Keele University, 2011. http://eprints.keele.ac.uk/2060/.

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For several historical and political reasons, the decision-making processes and institutional structures of environmental governance has been greatly impacted by the North-South dimension, which creates enormous challenges for Southern states when they try to present their concerns to global forums. These challenges have many dimensions, such as political, economic, social, and legal. This thesis recognises the “poverty of influence” that has become endemic as a result of the lack of resources, expertise, research facilities, technology and other practical deficiencies that exist in the negotiating procedures and which have hampered the South’s participation in global environmental governance. Such participatory inequalities between North and South have seriously hampered the application of equity, fairness and justice – principles that are considered to be vital ingredients in any balanced governing system. This thesis proposes the utilisation of the diverse capacity of transnational NGO networks to enable the Southern voice to be effectively heard in global decision-making processes, and it questions the traditional legal structures that currently allow for NGO involvement by determining the need for wider opportunities to be considered, thereby enabling them to express their concerns. The thesis includes a Case Study that examines from a North-South perspective the different capacities of NGOs to influence global forests negotiations. Consequently, it is hoped that the thesis will contribute towards a greater understanding of the benefits that might accrue from the utilisation of transnational networks to voice hitherto unheard global forest issues. This thesis, which is timely, in that 2011 was the International Year of Forests, argues that transnational NGO networks could help mitigate the inequalities suffered by the South caused by the historic North-South divide. However, it also stresses the importance attached to transnational NGO networks incorporating measurable values of legitimacy and accountability when they represent the South at global governance forums.

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Dodd, Celia Anne. "Synthetic and Natural Environmental Compounds as Potential Facilitators of Mptp-Induced Parkinsonism." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/26359.

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Parkinson's disease (PD) is a neurodegenerative Lewy body disorder characterized by severe motor deficits, followed by cognitive dysfunction with progression of the disease. Environmental exposure has been suggested as a possible contributor to the development of PD and this view is linked to the discovery of the nigrostriatal neurotoxin MPTP. MPTP can induce dopamine specific degeneration within the basal ganglia often resulting in motor deficits similar to PD. MPTP used in the C57BL/6 mouse is a widely used animal model of PD. The pyrethroid permethrin (PM), and the organophosphate chlorpyrifos (CPF), can produce changes in dopaminergic nigrostriatal neurons, the primary target of PD and MPTP-induced neurotoxicity. Such insecticide induced changes in the basal ganglia could exacerbate the onset or severity of PD. Chronic exposure to the metal manganese (Mn) can damage the globus pallidus (GP) of the BG, and produce motor deficits similar to PD. Since the GP is part of the BG circuitry essential for motor control, and is synaptically integrated with the nigrostriatal pathway, Mn may exacerbate MPTP-induced neurotoxicity. Because the BG is disynaptically linked to the mesocortical pathway, a dopaminergic pathway that is important for cognition, Mn induced damage in the BG could indirectly affect the mesocortical pathway as well. This study investigated the pesticides, permethrin and chlorpyrifos, and the heavy metal, manganese as possible environmental compounds that could exacerbate PD in the MPTP treated C57BL/6 mouse. The first part of this dissertation used immunohistochemistry to examine insecticide induced effets on MPTP-induced neurotoxicity in the dorsolateral striatum of the C57BL/6 mouse, the principal target of the nigrostriatal pathway. Tyrosine hydroxylase (TH) was used as a marker for loss of dopaminergic neuropil and glial fibrillary acidic protein (GFAP) was used as a marker of glial activation in the striatum. Three experiments assessed effects of 1) PM (200 mg/kg), 2) CPF (50 mg/kg) & 3) PM + CPF, on MPTP (30 mg/kg) neurotoxicity. Immunohistochemistry revealed a decrease in TH staining and an increase in GFAP staining with MPTP (30 mg/kg). A main effect increase in GFAP was observed for PM (200 mg/kg), but not for CPF (50 mg/kg) or PM+CPF. Insecticides, alone or combined, did not alter MPTP-induced toxicity. . However, the absence of the PM-induced increase in GFAP staining following combined insecticide treatment suggests a neuroprotective effect. The next set of experiments in this dissertation looked at the effect of Mn on MPTP-induced neurotoxicity in the nigrostriatal and mesocortical dopaminergic pathways of the C57BL/6 mouse. Inductively Coupled Plasma atomic emission spectrometry revealed striatal Mn levels were significantly increased with multiple dose 100, 50, and 25 mg/kg MnCl2. Administration of Mn (MnCl2 s.c., Days 1, 4, & 7) in the MPTP (20 mg/kg i.p., Day 8) treated C57BL/6 mouse revealed Mn and MPTP interactions for locomotor activity, grip strength, and repeated measures of learning. Mn attenuated the effect of MPTP on striatal DOPAC, and facilitated the effect of MPTP on cortical DA and DOPAC. Mn also attenuated the MPTP induced decrease in cortical DAT. While these data support the notion that insecticides can produce tissue damage in the nigrostriatal pathway, in this case, these insecticide induced changes were not found to be strong enough to facilitate PD-like tissue damage. While Mn did not always facilitate MPTP neurotoxicity in the mesocortical and nigrostriatal dopaminergic pathways, these results demonstrate Mn and MPTP can interact in a complex way to alter dopaminergic function as well as motor and cognitive behavior. Differences in brain uptake mechanisms and metabolism of Mn and MPTP, could explain why combined administration of Mn and MPTP differentially affect dopaminergic activity in the nigrostriatal and mesocortical pathways.
Ph. D.

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41

Tuttle, Meredith. "The Convergence of Environmental Influences as Potential Precipitating Factors of AML-M2." Youngstown State University / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1001949080.

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42

Luongo, Giovanna. "Chemicals in textiles : A potential source for human exposure and environmental pollution." Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-120010.

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The wide use of chemicals in textile production is common knowledge, whilst very little has been done to disclose the potentially harmful compounds hiding in our closet. The initial part of this work focused on explorative screening of textile materials in common clothing. Non-targeted analysis of a set of sixty garments revealed the presence of thousands of compounds, among which over a hundred were tentatively identified. Depending on the frequency of occurrence in textile, skin penetrating properties and toxicological data, candidate compounds were selected for confirmation. Analytical methods were developed for their identification and quantification, with focus set on four groups of compounds: quinolines, benzothiazoles, benzotriazoles and aromatic amines. The analytical methods are based on ultrasonic extraction, followed by solid phase clean-up, combined with GC/MS or LC/MS/MS analysis. Concentrations of many target analytes were notably higher in polyester samples compared to garments made from cotton and blended material. The release during washing was investigated for two of the compounds groups, quinolines and benzothiazoles. The decreased concentrations in the garments suggest that laundry is a source of emission of these chemicals into household wastewater, and possibly further into the aquatic environment. Due to the slow decrease of the concentration in the garments when washed, substantial amounts of the compounds will remain in the textiles for a long time, with the possibility of exposure to the skin of potential harmful compounds as a result.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 4: Manuscript. Paper 5: Manuscript.

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Parekh, Vishal. "A Fair Distribution of Global Biocapacity : The Potential in Swedish Environmental Policy." Thesis, KTH, Miljöstrategisk analys (fms), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-199684.

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Humanity’s detrimental impacts on the Earth’s ecosystems have been studied extensively, and these impacts’ negative consequences across societal groups, nations, and generations, have garnered much attention, from the scientific community as well as from civil society, where the attention often has been directed at how unfair the distribution of these environmental burdens is. The fairness of the distribution of global environmental benefits, however, has seen much less study, especially when it comes to the implementation of such concerns for fairness in environmental policy. In support of the research project Beyond GDP-growth, this thesis has centered on a Swedish context, and has focused on the term “biocapacity”, which is a quantifiable measure of many environmental benefits, and in the thesis is defined as the ability of terrestrial ecosystems to regenerate the biological materials extracted by humans. The thesis has then aimed to determine the current potential for the implementation of a fair distribution of global biocapacity in Swedish environmental policy, mainly by way of a series of interviews with individuals engaged in different forms of Swedish environmental work – from different levels of government, to civil society and centers of scientific research. It is concluded that the current potential for the implementation of a fair distribution of global biocapacity in Swedish environmental policy is primarily hindered by the seeming lack of a relevant discourse on the matter. Without such a discourse, a lack of public understanding of the subject is deemed to cause poor public support for any potential policies promoting a fair distribution of global biocapacity. It is suggested that a relevant and effective discourse is best achieved through transparent trade practices, and by the active participation of scientific experts and other actors outside of the political system. Furthermore, the thesis discusses the usefulness of the term “biocapacity” in this context, concluding that more research is needed, while identifying the main point of contention as what the term is intuitively understood to mean, as well as whether or not it can be used as a means to achieve a focused public discourse on the fair distribution of environmental goods.
Mänsklighetens skadliga inverkan på jordens ekosystem har studerats i stor utsträckning, och den här inverkans negativa konsekvenser för olika samhällsgrupper, länder och generationer har fått mycket uppmärksamhet från både forskningsvärlden och civilsamhället, där det främst har fokuserats på den orättvisa fördelningen av dessa ”miljöbördor”. Men, rättvisa när det kommer till fördelningen av ”miljönyttor” har studerats betydligt mindre, särskilt i samband med hur sådana rättviseaspekter kan implementeras i miljöpolicy. Den här uppsatsen har – i en svensk kontext och som stöd till forskningsprojektet Bortom BNP-tillväxt – fokuserat på en kvantifierbar term kallad ”biokapacitet”, som innefattar många miljönyttor, och i uppsatsen definieras som landbaserade ekosystems kapacitet att regenerera de biologiska material som människor extraherar. Uppsatsen har sedan ämnat att undersöka de nuvarande förutsättningarna för implementeringen av en rättvis fördelning av global biokapacitet i svensk miljöpolicy, främst genom en serie intervjuer med individer som i olika sammanhang är engagerade i svenskt miljöarbete – från kommunal till statlig nivå, samt i civilsamhället och i forskningssammanhang. Uppsatsen utmynnar i slutsatsen att de nuvarande förutsättningarna för implementeringen av en rättvis fördelning av global biokapacitet i svensk miljöpolicy främst begränsas av att den offentliga debatten till synes inte behandlar ämnet nämnvärt. Utan en offentlig debatt om ämnet förmodas den resulterande kunskapsbristen hos allmänheten leda till ett bristande offentligt stöd för policyförslag som förespråkar en rättvis fördelning av global biokapacitet. En relevant och effektiv offentlig debatt tros bäst kunna uppstå genom transparent handel och ett aktivt deltagande av experter från forskningsvärlden, samt andra utompolitiska aktörer. Dessutom diskuterar uppsatsen nyttan av begreppet ”biokapacitet” i en sådan debatt, och kommer fram till att vidare studier krävs för att nå en tillfredsställande slutsats. Uppsatsen identifierar dock den intuitiva uppfattningen av termens betydelse, samt frågan om termen kan användas för att uppnå en fokuserad debatt på ämnet, som de främsta problemområdena som behöver behandlas.
Beyond GDP-growth (sv. Bortom BNP-tillväxt)

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Tarr, Peter. "The potential role of environmental assessment in promoting sustainable development in Namibia." Thesis, University of Aberdeen, 1999. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU117436.

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The use of Environmental Assessment (EA) as a planning tool has been promoted in Namibia in recent years and a broad-based, consultative process to develop an umbrella Environmental Management Act, is underway. Most EAs conducted since 1990 were for prospecting and mining, and many were post-facto assessments that led to the development of Environmental Management Plans. This dissertation examines the links between sustainable development and EA, both from a theoretical perspective and on the basis of case study analysis. The objective is to assess the potential role of EA in promoting sustainable development in an arid, natural resource dependent, developing country. An overview of Namibia's socio-economic and environmental circumstances, development needs and options, past and current planning systems and commonalties within the region, provided a contextual setting for the analysis. The role of EA is assessed through a review of the planning and implementation of sector policies, plans, programmes and projects. A national questionnaire survey of decision makers provided insight into their knowledge, perceptions and attitudes towards EA. Finally, the dissertation considers the trial implementation of "fast-track EA" in the small-scale mining sector. It remains difficult to ascribe the appropriate implementation of activities to the influence of EA. However, the dissertation shows that EAs enhanced the way development activities were planned and implemented, especially when applied at the strategic level. Even at the project level, EAs improved planning and implementation when introduced early in the process. The lessons learnt in Namibia confirm that public participation is crucial to the success of EA. EAs that disappointed were those where the process was dominated by a single stakeholder or where authorities either excluded or unduly influenced public participation. By helping to minimise negative impacts, EAs have reduced opportunity cost and have thus promoted sustainable development. The dissertation makes a number of key recommendations including the creation of broad-based administrative structures to implement EA, the diversified application of Strategic EA and the development of "fast track EA" to guide the increasingly important small and informal sectors of Namibia's economy.

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Kumar, Vivekanandan. "Mechanistic studies on the potential role of environmental carcinogens in prostate cancer." Thesis, Institute of Cancer Research (University Of London), 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441410.

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Lopes, Miguel Ângelo de Freitas. "Industrial symbiosis potential of the Sines oil refinery – environmental and economic evaluation." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/11189.

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Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente – Perfil Gestão e Sistemas Ambientais
Industrial symbiosis is an application of industrial ecology that consists of a collaborative approach between different industries and firms aimed at improving their environmental and economic performance involving the exchange of waste/byproducts as substitutes for raw materials. This collaboration is conditioned by the geographic proximity between industries and may face some information, economic, regulatory or motivational barriers. The main objective of this thesis was to develop a methodology to find and evaluate new potential exchanges in light of industrial symbiosis and to apply it to Sines oil refinery case study. The methodology was divided into four phases. The first phase is where, through the analysis of similar case studies, the potential new exchanges are uncovered.The second was made based on a literature review on the main barriers to industrial symbiosis development. This phase was developed to swiftly filter potential synergies that would face barriers to its development. The other two phases were only applied to the potential synergies that successfully passed the “filter”. Those phases consisted of an environmental evaluation through a LCA and a financial analysis. The application of the methodology showed two new potential synergetic possibilities for the Sines oil refinery. The results of the evaluation of those potential synergies were very promising both environmentally and financially. This research thus demonstrates the potential and benefits associated with the development of industrial symbiosis networks if the barriers to this development can be successfully surpassed.

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Collins, James M. (James Michael) 1966. "The strategic potential of design-build in the information age." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/80925.

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Vanlian, Marie. "Assessment of anti-androgenic potential of candidate "green" dibenzoate plasticizers in mammalian MA-10 cells." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=117024.

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Plasticizers are additives to plastics that impart flexibility and the ability to process polymers. Unfortunately, due to their leaching potential and widespread use, they have become ubiquitous contaminants in the environment. Studies have correlated the rise of many health issues to the chronic exposure to these compounds and have suggested them as potential carcinogens and endocrine-disruptors. In particular, available evidence indicates that they disturb steroid production such as testosterone production and therefore, behave as anti-androgens. The seriousness of this issue has prompted researchers to develop "green" plasticizers to avoid adverse effects. In this thesis, a series of potential alternative plasticizers were screened for their anti-androgenic potential in vitro using a mouse Leydig tumor cell line, the MA-10 cells. Optimal solvent and plasticizer concentrations and time frame conditions were determined to ensure viability of the cells for the duration of the experiments. Using these optimized testing conditions, potential green plasticizers, including the 1,3-propanediol (C3), 1,4-butanediol (C4), 1,5-pentanediol (C5) and 1,6-hexanediol (C6) dibenzoates, were studied by monitoring their effects on progesterone synthesis. Based on these results and those of others from our group, the candidature of C4 is supported as a potential green plasticizer.
Les plastifiants sont des adjuvants ajoutés aux formulations de plastiques pour les rendre plus flexibles et plus faciles à manipuler. Malheureusement, étant donné leur tendance à migrer de la matrice polymère et leur utilisation répandue, ils sont devenus des contaminants environnementaux omniprésents. Des études ont corrélé la hausse de certaines maladies à l'exposition chronique à ces composés et évoquent leurs risques en tant que potentiels carcinogènes et perturbateurs endocriniens. Notamment, il y a évidence qu'ils perturbent la formation de certains stéroïdes dont la testostérone et ainsi, agissent comme des anti-androgènes. L'importance de ce sujet a incité les chercheurs à développer des plastifiants ‘verts' pour éviter les effets négatifs associés à ces composés. Dans cette thèse, des composés alternatifs ont été testés pour leur effet anti-androgène in vitro avec la lignée cellulaire tumorale interstitielle du testicule de souris, les cellules MA-10. Des concentrations optimales de solvant et plastifiants ainsi qu'une durée optimale d'exposition ont été déterminées afin d'assurer la viabilité des cellules au cours des expériences. En employant les conditions optimales établies, des composés sélectionnés en tant que potentiels plastifiants verts, incluant les dibenzoates de 1,3-propanediol (C3), de 1,4-butanediol (C4), de 1,5-pentanediol (C5) et de 1,6-hexanediol (C6), ont été étudiés en mesurant l'impact sur la synthèse de progestérone. Les résultats de cette étude, appuyés par d'autres résultats de notre groupe, démontrent le potentiel du C4 en tant que potentiel plastifiant vert.

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Swiger, J., Phillip R. Scheuerman, and Phillip R. Musich. "Determination of Potential Risk Associated with Cryptosporidium and Giardia in a Rural Water Source." Digital Commons @ East Tennessee State University, 1998. https://dc.etsu.edu/etsu-works/2916.

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Chitongo, Rumbidzai. "Antibiotics in the Diep River and potential abatement using grape slurry waste." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2575.

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Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2017.
Pharmaceuticals have found extensive application in human health management. They are released into the environment through urine, excreta and inappropriate disposal methods. Residues of pharmaceutical products have been reported to show toxic consequences in some freshwater and marine organisms. Antibiotics are one of the most important groups of common human pharmaceuticals widely in use as prescribed and non-prescribed drugs. Antibiotics and their metabolites have been quantitated in water and found in trace levels. But even at such low concentrations they can maintain high biological activities with potential adverse effects on humans and animals. Unfortunately, many pharmaceutical compounds are resistant to breakdown in the environment, hence they have tendency for environmental magnification, since they are designed to be biologically active. Therefore, there is need to evaluate their environmental levels and their possible abatement methods using simple, cheap and low cost techniques, in order to avert their potential toxic consequences. In this research, a cost effective, robust, selective and rugged method for the analysis of antibiotics in water samples using liquid chromatography was developed, and used for monitoring levels of the selected antibiotics in Diep River. Also, an effective remediation procedure for these contaminants in water was developed using activated carbon produced from grape slurry waste.

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Dissertations / Theses on the topic 'Environmental potential'

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