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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.
111

Aerosol characterization in the Southeastern U. S. using satellite data for applications to air quality and climate

Alston, Erica J. 19 January 2012 (has links)
Tropospheric aerosol information from NASA satellites in space has reached the milestone of ten years of continuous measurements. These higher resolution satellite aerosol records allow for a broader regional perspective than can be gained using only sparsely located ground based monitoring sites. Decadal satellite aerosol data have the potential to advance knowledge of the climatic impacts of aerosols through better understanding of solar dimming/brightening and radiative forcings on regional scales, as well as aid in air quality applications. The goal of this thesis is to develop and implement methodologies for using satellite remotely sensed data in conjunction with ground based observations and modeling for characterization of regional aerosol variations with applications to air quality and climate studies in the Southeastern U. S. This region is of special interest because of distinct aerosol types, less warming climate trends compared to the rest of U.S., and growing population. To support this primary goal, a technique is developed that exploits the statistical relationship between PM2.5 (particulate matter that has an aerodynamic radius of 2.5 µm or less) and satellite AOD (Aerosol Optical Depth) from MODIS (Moderate resolution Imaging Spectroradiometer) where a probabilistic approach is used for air quality assessments in the metropolitan Atlanta area. The metropolitan Atlanta area experiences the poorest air quality during the warmer seasons. We found that satellite AODs capture a significant portion of PM2.5 concentration variability during the warmer months of the year with correlation values above 0.5 for a majority of co-located (in time and space) ground based PM2.5 monitors, which is significant at the 95% confidence interval. The developed probabilistic approach uses five years of satellite AOD, PM2.5 and their related AQI (Air Quality Index) to predict future AQI based solely on AOD retrievals through the use of AOD thresholds, e.g., 80% of Code Green AQI days have AOD below 0.3. This approach has broad applicability for concerned stakeholders in that it allows for quick dissemination of pertinent air quality data in near-real time around a satellite overpass. Examination of the use of multiple satellite sensors to aid in investigating the impacts of biomass burning in the region is performed. The utility of data fusion is evaluated in understanding the effects of the large wildfire that burned in May 2007. This wildfire caused PM2.5 in the metropolitan Atlanta area to exceed healthy levels with some measurements surpassing 150 µg/m3 during the month. OMI (Ozone Monitoring Instrument) AI (Aerosol Index), which qualitatively measures absorbing aerosols, have high values of more than 1.5 during May 26 - 31, 2007. CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) a space based lidar was used to determine the vertical structure of the atmosphere across the region during the active fire period. CALIPSO was able to identify wildfire aerosols both within the planetary boundary layer (likely affects local air quality) and aloft where aerosol transport occurs. This has important implications for climatic studies specifically aerosol radiative effects. In-depth analysis of the satellite and ground based aerosol data records over the past decade (2000 - 2009) are performed from a climatic perspective. The long temporal scale allowed for better characterization of seasonality, interannual variability, and trends. Spatial analysis of ten years of AOD from both MODIS and MISR (Multi-angle Imaging Spectroradiometer) showed little variability of AOD during the winter with mean AOD below 0.1 for the entire region, while the summer had decidedly more variability with mean AOD around 0.33 for MODIS and 0.3 for MISR. Seasonal analysis of the PM2.5 revealed that summer means are twice as high as winter means for PM2.5. All of the datasets show interannual variability that suggests with time AOD and PM2.5 are decreasing, but seasonal variability obscured the detection of any appreciable trends in AOD; however, once the seasonal influence was removed through the creation of monthly anomalies there were decreasing trends in AOD, but only MODIS had a trend of -0.00434 (per month) that statistically significant at the 95% confidence level. Satellite and ground-based data are used to assess the radiative impacts of aerosols in the region. The regional TOA (Top Of the Atmosphere) direct radiative forcing is estimated by utilizing satellite AOD from MODIS and MISR both on Terra, along with satellite derived cloud fraction, surface albedo (both from MODIS), and single scattering albedo (SSA) from MISR data from 2000 - 2009. Estimated TOA forcing varied from between -6 to -3 W/m2 during the winter, and during the warmer months there is more variation with ΔF varying between -28 to -12.6 W/m2 for MODIS and -26 to -11 W/m2 for MISR. The results suggest that when AOD, cloud fraction and surface albedo are all consider they add an additional 6 W/m2 of TOA forcing compared to TOA forcing due to aerosol effects only. Varying SSA can create changes in TOA forcing of about 5 W/m2. With removal of the seasonal variability timeseries anomaly trend analysis revealed that estimated TOA forcing is decreasing (becoming less negative) with MODIS based estimates statistically significant at the 95% confidence level. Optical and radiative 1-D radiative transfer modeling is performed to assess the daily mean TOA forcing and forcing at the surface for representative urban and background aerosol mixtures for summer and winter. During the winter, modeled TOA forcing is -2.8 and -5 W/m2 for the WB and WU cases, and the modeled summer TOA forcings (SB = -13.3 W/m2) also generally agree with earlier estimates. While surface forcings varied from -3 to -210 W/m2. The radiative forcing efficiency at the TOA (amount of forcing per unit of AOD at 550 nm) varied from -9 to -72 W/m2 τ-1, and RFE at the surface varied from -50 to -410 W/m2 τ-1. It was found that the forcing efficiency for biomass burning aerosols are similar to the forcing efficiency of background aerosols during the summer that highlights the importance of possible increased biomass burning activity. Ultimately, the methodologies developed in this work can be implemented by the remote sensing community and have direct applicability for society as a whole.
112

Three essays in program evaluation the case of Atlanta inspection and maintenance program /

Supnithadnaporn, Anupit. January 2009 (has links)
Thesis (Ph.D)--Public Policy, Georgia Institute of Technology, 2009. / Committee Chair: Noonan, Douglas; Committee Member: Castillo, Marco; Committee Member: Chang, Michael; Committee Member: Cozzens, Susan; Committee Member: Rodgers, Michael. Part of the SMARTech Electronic Thesis and Dissertation Collection.
113

A remote sensing evaluation of the effectiveness of oxygenated fuels in the Raleigh, NC MSA

Rhudy, Scott Alan 08 1900 (has links)
No description available.
114

Development and application of ultrasound technology for treatment of organic pollutants

Thangavadivel, Kandasamy January 2010 (has links)
The necessity of cost effective, environmentally friendly technology has become increasingly important to remediate persistent organic pollutants in the environment. The emerging greener ultrasound technology has the potential to serve the remediation industry. In this study, the use of low power, high frequency (HF) ultrasound (1.6 MHz, 145 W/L) has been shown to effectively remediate DDT (90% of 8 mg/L) in water and sand slurries. Addition of iron powder accelerated DDT degradation in the sand slurry under ultrasonication. The potential of HF ultrasound (1.6 MHz, 160 W/L) in degradation of the non-volatile, polar model compound methylene blue (MB) was studied in MB spiked demineralised water and wastewater. A 70 % of 0.4 mg/L of MB was degraded in demineralised water whereas only 54% of MB degraded in MB spiked wastewater. There was a decrease in MB degradation rate with an increase in MB concentration. High power, low frequency (LF) ultrasound (20 kHz, 932 W/L) was used to desorb 400 mg/L of DDT added to three different natural soil slurries at 5, 10, 15 and 20 wt. % each. Each soil slurry was prepared in 0.1% v/v SDS surfactant solution, soaked for 30 min. and heated for another 30 min. at 40 oC before sonication. For the neutral pH soil slurry with higher dissolved organic carbon, the desorption efficiency achieved was over 80% in 30 s sonication. Alkaline soil with higher surface area than neutral soil indicated 60% desorption efficiency while the acidic soil, with the highest surface area and a higher amount of non-soluble organic matter, yielded 30% desorption efficiency under similar desorption conditions. Coconut fibre, used to biosorb the desorbed DDT in the decanted solution, was found to have over 25 g/kg of biosorption capacity for DDT. The surfactant SDS and associated DDT were completely separated from decanted liquid of the desorbed slurry with alum using adsorptive micellar flocculation in 60 min. settling. Acidic pH and molar concentration ratio of Al3+/SDS = 0.5 was used to completely remove the DDT. Using 20 kHz, 1125 W/L of sonication in an 80 mL reactor with air saturated 50 mg/L DDT at 20oC, the DDT removal efficiency achieved was 80% in 20 min. With zero valent iron addition, DDT removal efficiency in 15 min. is 100% with 15 and 22 mg/L of initial DDT concentrations. The settled DDT slurrywas remediated using 20 kHz at 240 W/L achieving DDT removal efficiency of 87% in 15 min. Also LF ultrasound was found to be effective in remediating chloroform (8 mg/L in 60 min) from spiked demineralised water and contaminated groundwater in both batch (120 W/L) and flow cell (6000 W/L) modes. Modeling and simulation of the ultrasonic reactor under 20 kHz ultrasonication was performed for various shape reactors using commercially available software. For almost all reactors, the highest ultrasonic intensity was observed near the transducer???s vibrating area. It was found that the highest acoustic pressure distribution, which is critical to the performance of the reactor, occurred in the conical reactor and flow cell configuration. / Thesis (PhD)--University of South Australia, 2010
115

Development and application of ultrasound technology for treatment of organic pollutants

Thangavadivel, Kandasamy January 2010 (has links)
The necessity of cost effective, environmentally friendly technology has become increasingly important to remediate persistent organic pollutants in the environment. The emerging greener ultrasound technology has the potential to serve the remediation industry. In this study, the use of low power, high frequency (HF) ultrasound (1.6 MHz, 145 W/L) has been shown to effectively remediate DDT (90% of 8 mg/L) in water and sand slurries. Addition of iron powder accelerated DDT degradation in the sand slurry under ultrasonication. The potential of HF ultrasound (1.6 MHz, 160 W/L) in degradation of the non-volatile, polar model compound methylene blue (MB) was studied in MB spiked demineralised water and wastewater. A 70 % of 0.4 mg/L of MB was degraded in demineralised water whereas only 54% of MB degraded in MB spiked wastewater. There was a decrease in MB degradation rate with an increase in MB concentration. High power, low frequency (LF) ultrasound (20 kHz, 932 W/L) was used to desorb 400 mg/L of DDT added to three different natural soil slurries at 5, 10, 15 and 20 wt. % each. Each soil slurry was prepared in 0.1% v/v SDS surfactant solution, soaked for 30 min. and heated for another 30 min. at 40 oC before sonication. For the neutral pH soil slurry with higher dissolved organic carbon, the desorption efficiency achieved was over 80% in 30 s sonication. Alkaline soil with higher surface area than neutral soil indicated 60% desorption efficiency while the acidic soil, with the highest surface area and a higher amount of non-soluble organic matter, yielded 30% desorption efficiency under similar desorption conditions. Coconut fibre, used to biosorb the desorbed DDT in the decanted solution, was found to have over 25 g/kg of biosorption capacity for DDT. The surfactant SDS and associated DDT were completely separated from decanted liquid of the desorbed slurry with alum using adsorptive micellar flocculation in 60 min. settling. Acidic pH and molar concentration ratio of Al3+/SDS = 0.5 was used to completely remove the DDT. Using 20 kHz, 1125 W/L of sonication in an 80 mL reactor with air saturated 50 mg/L DDT at 20oC, the DDT removal efficiency achieved was 80% in 20 min. With zero valent iron addition, DDT removal efficiency in 15 min. is 100% with 15 and 22 mg/L of initial DDT concentrations. The settled DDT slurrywas remediated using 20 kHz at 240 W/L achieving DDT removal efficiency of 87% in 15 min. Also LF ultrasound was found to be effective in remediating chloroform (8 mg/L in 60 min) from spiked demineralised water and contaminated groundwater in both batch (120 W/L) and flow cell (6000 W/L) modes. Modeling and simulation of the ultrasonic reactor under 20 kHz ultrasonication was performed for various shape reactors using commercially available software. For almost all reactors, the highest ultrasonic intensity was observed near the transducer???s vibrating area. It was found that the highest acoustic pressure distribution, which is critical to the performance of the reactor, occurred in the conical reactor and flow cell configuration. / Thesis (PhD)--University of South Australia, 2010
116

Topics on the ecological economics of coastal zones : linking land uses, marine eutrophication, and fisheries /

Paulsen, Sandra Silva, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
117

[en] INDUSTRIAL WASTE MANAGEMENT OF EXPLORATORY MARITIME DRILLING ACTIVITY ON THE COAST OF BAHIA STATE: CASE STUDY OF BLOCK BM-J-2 / [pt] GERENCIAMENTO DE RESÍDUOS INDUSTRIAIS DE ATIVIDADE DE PERFURAÇÃO MARÍTIMA EXPLORATÓRIA NO ESTADO DA BAHIA: ESTUDO DE CASO DO BLOCO BM-J-2

THAYS PAES CABRAL AMARO 22 December 2017 (has links)
[pt] A análise e comparação dos dados de geração, transporte, tratamento e destinação final dos resíduos sólidos gerados durante as duas campanhas (2011 e 2013) da atividade de perfuração marítima exploratória no Bloco BM-J-2, sem e com a utilização de uma área de armazenamento temporário de resíduos exclusiva para esta operação teve como objetivo verificar a aplicabilidade dessas duas alternativas de operacionalização do gerenciamento de resíduos em regiões onde a indústria de exploração e produção de petróleo e gás não está consolidada. O atendimento aos requisitos legais brasileiros, com a implementação do Projeto de Controle da Poluição para atendimento às orientações da Nota Técnica CGPEG/DILIC/IBAMA numéro 01/11, permitiu que os dados gerados durante as duas campanhas de perfuração pudessem ser comparados, ainda que gerados em momentos operacionais distintos. A similaridade do perfil de geração de resíduos nos dois períodos de operação e os resultados das diferentes estratégias de gerenciamento adotadas, permitiu definir a utilização da área de armazenamento temporário, ainda que exclusiva e construída para atendimento à operação, como melhor estratégia de gerenciamento também para regiões em que a indústria de EeP ainda não está consolidada, com incremento qualitativo das formas de tratamento e disposição final adotadas e melhoria de indicadores quantitativos, como redução do número de eventos de transporte. / [en] The analysis and comparison of generation, transportation, treatment and final disposal data of the solid waste, generated during two campaigns (2011 and 2013) of exploratory offshore drilling activity in Block BM-J-2, with and without the use of a waste temporary storage exclusive area for this operation aimed to verify the applicability of these two waste management operational alternatives in regions where the oil and gas exploration and production industry is not consolidated. The compliance with Brazilian legal requirements, with the implementation of Pollution Control Project according to Technical Note CGPEG / DILIC / IBAMA number 01/11 guideline, allowed the comparision of data generated during the two drilling campaigns, even though they have been generated in different moments. The similarity of waste generation profiles of both operational periods and the results of different management strategies adopted, allowed to define the use of the temporary storage area, even if exclusive and built for the operation, as the best management strategy for regions where the EeP industry still not consolidated, with qualitative increase of treatment and disposal methods adopted and quantitative indicators improvement, as reduction of transport events.
118

Propriedade das normas de lançamento de esgoto / Properties of the norms of sewer release

Amigo, Nisete Augusto de January 1998 (has links)
Made available in DSpace on 2012-09-06T01:11:12Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 106.pdf: 3009480 bytes, checksum: 3073b80b6df5fc1810662a9fd636a233 (MD5) Previous issue date: 1998 / Fundação Oswaldo Cruz. Escola Nacional de Saúde Pública Sergio Arouca. Rio de Janeiro, RJ, Brasil. / As normas utilizadas na avaliaçäo de lançamento de esgotos, NT-202, DZ-205 e DZ-215, foram utilizadas, para verificar se os esgotos domésticos, portanto de origem näo industrial, realmente mantêm esta condiçäo nos dias atuais, década de 90 e com cinqüenta anos de evoluçäo da industria química. O esgoto bruto, estudado, representativo de uma populaçäo de 4000 habitantes, apresentou uma carga orgânica unitária de 98 g/hab.d, maior do que a prevista pela DZ-215, que é de 54 g/hab.d. A concentraçäo de MBAS encontrada, de 6,09 mg/l, é maior que a concentraçäo permitida pela NT-202 para o lançamento industrial, na rede de esgotos, que é de 2,0 mg/l; implica num consumo percapita de surfactante de 2,9 g/hab.d, contra 4,0g/hab.d previstos na Europa Ocidental (Painter & Zabel, 1988) e 4,5 g/hab.d em Owlwood, U.K (Holt, et al., 1995). Os metais pesquisados estäo todos abaixo dos valores preconizados pela NT-202. O cádmio foi o que registrou maior percentual comparado com limite exigido, 29 por cento , seguido igualmente do chumbo e do zinco com 18 por cento, e, ainda, a maior variaçäo percentual de crescimento do consumo percapita. Esse crescimento poderia ser uma tendência ligada ao consumo exagerado, quer por desperdício ou excesso de oferta de produtos, somado, provavelmente, ao controle inadequado desses elementos nos produtos. A relaçäo DBO/DQ, de referência para a NT-205 (FEEMA, 1991) como indicativo da necessidade de implantaçäo de sistema de pré-tratamento de controle de carga orgânica näo-biodegradável, a ser lançada na rede de esgotos, por uma atividade poluidora industrial. Essas tendências devem ser consideradas, para que se busque formas de controle aplicáveis aos esgotos domésticos, ante a expectativa de mais alteraçöes futuras. A carga industrial, pontual, pode ser devidamente controlada para näo agredir o meio ambiente, ou, aos cofres públicos, com demandas näo previstas para as ETE'S. O controle de uma carga difusa - esgoto doméstico - formada pelos mais variados produtos domissanitários, cosméticos e de higiene, exigirá, num futuro próximo, outras formas de controle, para que näo atinja valores que venha a comprometer o tratamento municipal de esgotos e o meio ambiente. / The FEEMA regulations to valuation sewers throwing, NT-202, DZ-205 and DZ-215, were used in order to verify if the domestic sewers, thus of non-industrial origin, really maintain this condition nowadays, in the ninety’s, and with fifty years of evolution of chemical industry. The raw sewer, up in this work, representative of a population of 4.000 inhabitants, presented an unitary organic load of 98 g/cap.d, larger than that expected by DZ-215, that is of 54g/cap.d. The founded MBAS concentration, of 6.09 mg/l, is larger than the NT-202 standard concentration for industrial throwing in the sewerage system, that is of 2.0 mg/l. This imply in a “per capita” surfactant consumption of 2.9 g/cap.d, against 4.0 g/cap.d foreseen in the Western Europe (Painter & Zabel, 1988) and 4.5 g/cap.d in Owlwood, U.K. (Holt, et al, 1995). The researched metals are all lower than the NT-202 standardized values. The cadmium was the one that recorded the larger percentage, compared with the required standard values, 29%, followed equally by lead and zinc with 18%, and yet, the larger percentage variation of “per capita” consumption increase. This increase could be a tendency associated to an excessive consumption, that by wastefulness or a surplus in the products supply, probably added to the inadequate control of these elements in the products. The found average relation BOD/QOD was 0.6 ± 0.17mg/l. The relation BOD/QOD was 2.3±0.7mg/l, having reached in some samples a value higher than 4:1, which value is the background to indicate the necessity of introduction of pre-treatment system (FEEMA, NT-205) as an indicative to control a non-biodegradable organic load, to be thrown in the sewerage system, by an industrial polluter activity. This tendency must be considerate in order to search control lines to be applied in domestic sewers, foreseeing further future changes. The industrial load, can be properly controlled for d’ont pollute the environment or give rise to public costs, with contests unforeseen loads for the ETE’s. The control of a diffuse load - domestic sewer - composed of the most varied household, cosmetics and hygienic products, will demand, in the near future, other lines of control, to the effect of do not reach values that could compromise the municipal sewers treatment and the environment.
119

Estudo para conversao de partes poluentes dos gases de combustao de termoeletrica a oleo em materia prima para fertilizante

ALY, OMAR F. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:55Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:48Z (GMT). No. of bitstreams: 1 07173.pdf: 11277724 bytes, checksum: 5b5dfb2b888fca36e76b5cf99fdb18ab (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares, Sao Paulo
120

Uso do hidrogênio no transporte público da cidade de São Paulo / Use of hydrogen in the public transport of sao paulo city

PALADINO, PATRICIA A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:55Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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