• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 487
  • 133
  • 51
  • 49
  • 21
  • 18
  • 14
  • 13
  • 11
  • 8
  • 5
  • 3
  • 3
  • 3
  • 2
  • Tagged with
  • 987
  • 987
  • 235
  • 205
  • 205
  • 186
  • 130
  • 129
  • 111
  • 81
  • 77
  • 76
  • 76
  • 73
  • 71
  • 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.
391

Pedestrianization in Hong Kong: its impacts on air quality and human response.

January 2001 (has links)
Kam Wai-ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 153-162). / Abstracts in English and Chinese ; questionnaire in Chinese. / List of Tables --- p.x / List of Figures --- p.xiii / List of Abbreviation --- p.xvi / Chapter Chapter One --- Introduction --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- The Research Problems --- p.2 / Chapter 1.3 --- Objectives of the Study --- p.4 / Chapter 1.4 --- Study Area --- p.4 / Chapter 1.5 --- Significance of the Study --- p.8 / Chapter 1.6 --- Organization of Thesis --- p.9 / Chapter Chapter Two --- Literature Review --- p.11 / Chapter 2.1 --- Pedestrianization: Basic Ideas and History --- p.11 / Chapter 2.1.1 --- Definition of Pedestrianization --- p.11 / Chapter 2.1.2 --- Motivation of pedestrianization --- p.13 / Chapter 2.1.3 --- Learning from the Development of Pedestrianization in Other Cities --- p.15 / Chapter 2.1.4 --- Impacts of Pedestrianization on Environment --- p.19 / Chapter 2.2 --- Pedestrianization in Hong Kong --- p.21 / Chapter 2.2.1 --- Development --- p.21 / Chapter 2.2.2 --- Ways for Successful Pedestrianization in Hong Kong --- p.22 / Chapter 2.3 --- Human Perception and Response on Air Pollution and Pedestrianization --- p.24 / Chapter 2.3.1 --- Introduction of Human Perception --- p.24 / Chapter 2.3.2 --- Human Perception of Air Pollution --- p.27 / Chapter 2.3.3 --- Changes of Human Perception in Response to the Changes of Environmental Quality After Pedestrianization --- p.31 / Chapter Chapter Three --- Methodology --- p.34 / Chapter 3.1 --- Research Design --- p.34 / Chapter 3.2 --- BACIPR Approach --- p.35 / Chapter 3.3 --- Objective Assessment of the influence of pedestrianization on air quality --- p.38 / Chapter 3.3.1 --- Model Prediction --- p.39 / Chapter 3.3.2 --- Physical Measurement of Particulates --- p.46 / Chapter 3.4 --- Subjective Assessment: Human Perception of Roadside Air Pollution --- p.56 / Chapter 3.4.1 --- Guidelines Used for Subjective Assessment --- p.57 / Chapter 3.4.2 --- Development of the Questionnaire --- p.58 / Chapter 3.4.3 --- Statistical Analysis --- p.59 / Chapter Chapter Four --- Model Simulation of the Effect of Pedestrianization on Air Quality --- p.61 / Chapter 4.1 --- Introduction --- p.61 / Chapter 4.2 --- Air Quality in Causeway Bay Before Pedestrianization --- p.64 / Chapter 4.2.1 --- Overall Spatial Variation of Air Quality --- p.64 / Chapter 4.2.2 --- Respiratory Suspended Particulate (RSP) --- p.67 / Chapter 4.2.3 --- Nitrogen Dioxide (N02) --- p.68 / Chapter 4.2.4 --- Carbon Monoxide (CO) --- p.69 / Chapter 4.3 --- Air Quality in Causeway Bay After Pedestrianization --- p.70 / Chapter 4.3.1 --- Overall Spatial Variation of Air Quality --- p.70 / Chapter 4.3.2 --- Respiratory Suspended Particulate (RSP) --- p.70 / Chapter 4.3.3 --- Nitrogen Dioxide (N02) --- p.73 / Chapter 4.3.4 --- Carbon Monoxide (CO) --- p.75 / Chapter 4.3.5 --- Effect of Government's Pedestrianization Scheme in Improving Air Quality --- p.77 / Chapter 4.4 --- Air Quality Impact of Pedestrianization in Single Street --- p.77 / Chapter 4.4.1 --- RSP Concentration in Russell Street Section Before Pedestrianization --- p.78 / Chapter 4.4.2 --- RSP Concentration in Russell Street Section After Pedestrianization --- p.81 / Chapter 4.5 --- Summary and Conclusion --- p.83 / Chapter Chapter Five --- Measurement of Particulate Pollution in Causeway Bay --- p.84 / Chapter 5.1 --- Change in Particulate Pollution After Pedestrianization in Russell Street --- p.86 / Chapter 5.1.1 --- Overall Changes in Particulate Pollution after Pedestrianization --- p.86 / Chapter 5.1.2 --- Changes in Particulate Pollution after Pedestrianization under Different Weather Conditions --- p.87 / Chapter 5.1.2.1 --- Effects of Pedestrianization on Fine Day --- p.88 / Chapter 5.1.2.2 --- Effects of Pedestrianization on Rainy Days --- p.89 / Chapter 5.1.3 --- Changes of Particulate Pollution after Pedestrianization under Different Traffic Flow Conditions --- p.90 / Chapter 5.1.3.1 --- Effects of Pedestrianization during Peak Hours --- p.91 / Chapter 5.1.3.2 --- Effects of Pedestrianization during Non-Peak Hours --- p.92 / Chapter 5.1.4 --- Changes in Particulate Pollution As a result of Pedestrianization on Different Days of the Week --- p.93 / Chapter 5.1.4.1 --- Effects of Pedestrianization on Weekdays --- p.94 / Chapter 5.1.4.2 --- Effects of Pedestrianization on Non-Weekdays --- p.94 / Chapter 5.1.5 --- Change in PM 10 I/C ratio After Pedestrianization --- p.95 / Chapter 5.2 --- Variations in Particulate Pollution Characteristics Due to Different Pedestrianization Street Designs --- p.96 / Chapter 5.2.1 --- General Contrasts between an Open and Semi-enclosed Street --- p.97 / Chapter 5.2.2 --- Seasonal Effect on Particulate Pollution in Jardine's Crescent and in Its Control Street --- p.97 / Chapter 5.2.3 --- Climatic Effects on Particulate Pollution --- p.101 / Chapter 5.2.4 --- Effects of Traffic Conditions on Particulate Pollution Pattern in Jardine's Crescent and in Its Control Street --- p.102 / Chapter 5.2.5 --- Effects of Day of the Week on Particulate Pollution --- p.104 / Chapter 5.3 --- The Variation of Particulate Pollution in Causeway Bay --- p.105 / Chapter 5.3.1 --- Spatial Variation --- p.105 / Chapter 5.3.2 --- Seasonal Variation --- p.108 / Chapter 5.3.3 --- Rain as a Cleaning Agent --- p.111 / Chapter 5.4 --- Summary and Conclusion --- p.112 / Chapter Chapter Six --- Pedestrianization and Perception of Air Quality --- p.113 / Chapter 6.1 --- Introduction --- p.113 / Chapter 6.2 --- Effect of Pedestrianization in Improving the Perceived Air Quality --- p.115 / Chapter 6.2.1 --- Overall Changes of PAQ after Pedestrianization --- p.115 / Chapter 6.2.2 --- Changes in Perceived Air Quality As a Result of Pedestrianization --- p.118 / Chapter 6.2.2.1 --- Correlation between PAQ and AQ --- p.118 / Chapter 6.2.2.2 --- Difference in Dose-Response Relationships before and after Pedestrianization --- p.120 / Chapter 6.2.3 --- Summary of Findings on Human Perception --- p.136 / Chapter 6.3 --- Aspects of Pedestrianization Which Improve Perceived Air Quality --- p.136 / Chapter 6.3.1 --- Behavior Constraint Model --- p.137 / Chapter 6.3.2 --- Environmental Stress Model --- p.139 / Chapter 6.3.3 --- Perception of Air Pollution Through Smell and Vision --- p.141 / Chapter 6.4 --- Summary and Conclusion --- p.144 / Chapter Chapter Seven --- Conclusion --- p.146 / Chapter 7.1 --- Summary of Findings --- p.146 / Chapter 7.1.1 --- Model Simulated Air Pollution Levels in Causeway Bay and Possible Effects of the Government Pedestrianization Scheme --- p.147 / Chapter 7.1.2 --- Changes in the Pattern and Characteristics of Particulate Pollution after Pedestrianization --- p.148 / Chapter 7.1.3 --- Effects of Pedestrianization on Human Perception of Air Quality --- p.149 / Chapter 7.2 --- Discussion of Findings --- p.151 / References --- p.153 / Appendix A --- p.163
392

Reatividade fotoquímica da atmosfera de Cubatão e a influência de fontes exógenas / Silva, M. F. Photochemical reactivity of the atmosphere of Cubatão and the influence of exogenous pollutants: 2012

Silva, Moacir Ferreira da 11 March 2013 (has links)
Objetivo. Demonstrar que a ocorrência de episódios críticos de poluição por ozônio na região de Cubatão-Centro é influenciada pelo aporte externo de poluentes, que participam dos processos físico-químicos de formação e remoção de reagentes fotoquímicos na atmosfera. Métodos. O estudo envolveu a obtenção e o tratamento de dados meteorológicos e de concentrações de poluentes fornecidos pela rede de monitoramento da qualidade do ar, bem como a realização de campanhas de amostragem passiva de ozônio (O ) e ativa de COVs, aldeídos e etanol na atmosfera da região. A amostragem de O VI 3 foi realizada com amostradores tipo Ogawa® e as concentrações foram determinadas por cromatografia iônica, com detecção por condutividade elétrica. Na amostragem de COVs foram utilizados tubos de aço contendo o adsorvente Tenax-GR, e a quantificação das amostras foi realizada por cromatografia gasosa e espectrometria de massas. A amostragem de aldeídos foi realizada com cartuchos de sílica gel revestido com 2,4 DNPH, e a quantificação realizada por cromatografia liquida de alta performance, com detector ultravioleta (UV/VIS). A amostragem de etanol foi realizada com cartuchos revestidos de florisil, e a quantificação realizada por flame ionization detector. O transporte de massas de ar foi analisado com base em backward trajectories, calculadas pelo modelo STILT. A interpretação dos dados foi realizada por estatística descritiva, boxplot, análise de correlação e análise multivariada (clusters). Resultados. A maioria dos episódios de ultrapassagem do PQAr de ozônio ocorreu no verão, entre 15h e 16h, com ventos predominantes de S/SE e velocidades superiores a 2,5m/s, típicos de períodos diurnos (brisa marítima). As espécies orgânicas precursoras de ozônio mais importantes foram: formaldeído, acetaldeído, tolueno, 1,2,3-trimetilbenzeno, m-xileno, etanol, oxileno, etilbenzeno, 1,3,5-trimetilbenzeno e benzeno. A retrotrajetória das massas de ar que chegam à Cubatão-Centro comprovou a influência de emissões exógenas. Os resultados obtidos na circulação de mesoescala, simulada pelo modelo BRAMS, concordam com os resultados obtidos por JAESCHKE (1997), onde apenas uma parcela da concentração média de poluentes de Cubatão-Centro era oriunda de fontes locais, sendo o restante decorrente do transporte de massas, com ocorrência de elevadas concentrações de poluentes com fluxo de direção norte-noedeste (brisa terrestre) e sul-sudeste (brisa marítima) / Objective. Demonstrate that critical episode occurrences of air pollution are influenced by external input of pollutants that participate in the processes of atmospheric photochemical reagent formation and removal. Methods. The study involved meteorological data collection and processing of pollutant concentration data gathered by the air quality monitoring network. Campaigns of passive sampling of O and active sampling of VOCs, aldehydes and ethanol in the atmosphere of the region were also performed. The O 3 sampling was conducted with the Ogawa ® type samplers and the concentrations were determined by ion chromatography with electrical conductivity detector. VOCs sampling was performed using steel tubes containing Tenax GR adsorbent, and quantification was done by gas chromatography and mass spectrometry. Aldehyde sampling was performed with silica gel cartridges coated with 2,4 DNPH and quantification done by High Performance Liquid Chromatography (HPLC) with ultraviolet detector (UV / VIS). Ethanol sampling was performed with florisil coated cartridges and quantification by flame ionization detector. The transport of air masses was analyzed based on Backward trajectories calculated by the model STILT. Interpretation of the data was performed using descriptive statistics, boxplots, correlation analysis and multivariate analysis (clusters). Results. Most episodes of Ozone exceeding Air Quality Standards occurred in the summer, between 15h and 16h, with prevailing winds from S / SE and with velocities greater than 2.5 ms -1 , typical of day periods (sea breeze). Major ozone precursor organic species are: formaldehyde, acetaldehyde, toluene, 1,2,3-trimethylbenzene, m-xylene, ethanol, xylene, ethylbenzene, 1,3,5trimethylbenzene and benzene. The retro trajectory of air masses arriving at Cubatão-Center proved the influence of exogenous emissions. Results in the mesoscale circulation given by model simulation by BRAMS, agree with the results obtained by JAESCHKE (1997), showing that only a portion of the average concentration of pollutants Cubatão-Centro was due to local sources, with the rest resulting from the transport of masses, with the occurrence of high concentrations of pollutants resulting when flow directions are from NW (land breeze) and SE (sea breeze).
393

Particle-associated air toxics exposure risk among inner city adolescents

Geba, Gregory Peter January 2014 (has links)
The increase in global population witnessed over recent years poses major threats to the quality of the air we breathe. Coupled with population growth in many developed countries, often driven by immigration, there have been substantial increases in the populations of developing countries. At the same time, an increasing number of individuals live in urban environments. In order to assess risk of exposure to hazardous air pollutants (air toxics) in the inner city, where a susceptible population resides, data obtained from high school students in the New York and Los Angeles TEACH (Toxic Exposure Assessment: A Columbia-Harvard Study) studies, were analyzed, with the three main objectives to: 1). Assess, characterize, quantify and compare directly-measured personal air toxics exposures from New York and Los Angeles; 2). Assess, quantify and compare the concentrations and temporal and spatial variability of air toxics measured in the outdoor urban microenvironments of these two cities; 3). Determine if personal air toxics exposures could be modeled using available time-activity information, coupled with measured microenvironmental air pollution inputs. The main findings of this research revealed substantial differences between New York and Los Angeles in the quantity and quality of particle-associated personal air toxics exposures in these two cities. Students across cities exhibited similar levels of personal exposure to particulate matter (PM 2.5) and to high levels of sulfates (greater in Los Angeles than New York; both likely of vehicular traffic origin). Different patterns of exposure to particle-associated air toxics was observed in the two cities and across seasons. In New York, students demonstrated substantially higher exposures to iron, cobalt, and manganese, likely of subway origin, than their counterparts in Los Angeles, who exhibited higher exposures to calcium, aluminum, magnesium (likely of crustal origin). Across seasons, within cities, differences were also detected, with higher levels of air toxics exposures shown in New York in the winter than in the summer for nearly 80% of the analytes, similar to the general pattern (winter vs. fall) in Los Angeles. With respect to outdoor air toxics concentrations, in general terms, crustal sources of air toxics were detected in both cities, though in Los Angeles these levels tended to be higher than in New York, often significantly. Anthropogenic sources were evident in each of the cities to varying degrees. Sulfates were detected at comparable high levels across both cities, though the levels tended to be higher and variability of concentrations of this air pollutant was greater Los Angeles than New York, likely reflecting differences both in patterns of traffic and built environment. Various approaches taken to model spatial and temporal variability of outdoor air toxics concentrations using mixed procedures showed city-specific, spatial and temporal variance patterns of air toxics. Using location and time (day) inputs, in New York, Zn, Pt, and Sn were among the elements with highest spatial variability in the summer, whereas in the winter, Co and La (possibly of subway origin) showed high spatial-temporal variance. In Los Angeles on the other hand, highest spatial to temporal variance ratios were noted for Cs, Ni and K in the fall and Ni, As and Mg in the winter. Each city also revealed different patterns of temporally dominant air toxics, consistent with variable-in-time excursions in air toxics reflecting remote, upwind sources. Using regression modeling that accounted for the distribution of measured personal air toxics, coupled with available time-activity diary data from TEACH and assignment of those activities to specific measured microenvironments, modeling of personal exposures yielded generally strong coefficients of determination, explanatory power and could be cross-validated. Important findings included the role of the indoor environment in predicting personal exposures and the degree to which a small percentage of time spent in the transit environment could affect exposures to trace elements from this source. Although the majority of elements could be predicted in large part by indoor exposures, not simply as a reflection of outdoor air toxics concentrations, the inclusion of other microenvironments, in many cases substantially increased the predictive power of the models generated. The research pursued in this thesis project further details and underscores the risk of air toxics exposures of young residents of the inner city, which, unlike workplace and environmental standards that traditionally may have been based on single exposures, are characterized by exposures to low level complex mixtures of air toxics. In aggregate, these mixtures may have different health consequences than more intense single pollutant exposures. Data generated here may help to inform planning of air quality monitoring approaches in the inner city, as well as provide one template for predictive modeling of human exposures to air toxics in that complex environment, to reduce the need for direct personal measurements to assess exposure risk. This may ultimately contribute to approaches to mitigate air toxics exposures and its consequences for an expanding global population residing in the world's inner cities.
394

Poluição e qualidade do ar, modelagem ambiental da dispersão dos poluentes de fonte fixa / Contaminacion y calidad del aire, modelamiento ambiental de la dispersion de contaminantes de fuente fija

Valenzuela Saavedra, Gabriel Cristóbal 28 March 2018 (has links)
Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2018-04-23T11:10:57Z No. of bitstreams: 2 Dissertação - Gabriel Cristóbal Valenzuela Saavedra - 2018.pdf: 4929181 bytes, checksum: 32d6c5535f93ba6a8920d6f67beb26e8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-04-23T11:57:24Z (GMT) No. of bitstreams: 2 Dissertação - Gabriel Cristóbal Valenzuela Saavedra - 2018.pdf: 4929181 bytes, checksum: 32d6c5535f93ba6a8920d6f67beb26e8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-23T11:57:24Z (GMT). No. of bitstreams: 2 Dissertação - Gabriel Cristóbal Valenzuela Saavedra - 2018.pdf: 4929181 bytes, checksum: 32d6c5535f93ba6a8920d6f67beb26e8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-28 / Outro / El presente estudio tiene como finalidad encontrar un camino metodológico para modelar la dispersión de contaminantes atmosféricos provenientes de fuentes de emisión fija, a través de materiales baratos y simples. El camino insto de la revisión teórica de los principales conceptos de la contaminación atmosférica y la calidad del aire, así conocer cuales factores determinan áreas vulnerables a la contaminación atmosférica. Se usó una fuente de emisión fija de una industria alimentaria para mostrar un análisis de lo que sería un estudio de impacto ambiental de las emisiones producto de la operación normal de la fábrica para el año 2012, sin la intención de evaluar, si no, para mostrar cómo se aplica el modelo en un caso práctico. De esta forma, colocar en disposición una metodología que pueda ser usada en estudios que ayuden a la toma de decisión para la planificación en la introducción de nuevas fuentes de emisión o la alteración de las antiguas. Como resultado, se consiguen imágenes donde es fácilmente reconocible el área de susceptibilidad de las emisiones provenientes de la fuente fija, las que son interpretadas para aclarar que podría pasar frente a los diversos escenarios posibles. / O presente estudo teve como objetivo encontrar o caminho metodológico para modelar a dispersão de poluentes atmosféricos provenientes de fontes de emissão fixa, através de materiais baratos e simples. O percurso instou da revisão teórica e dos principais conceptos da poluição e qualidade do ar para saber quais são os fatores que determinam áreas vulneráveis à poluição atmosférica. Usou-se uma fonte de emissão atmosférica fixa de uma indústria alimentar para mostrar um analises do que seria um estudo de impacto das emissões produto da operação normal da fábrica para o ano 2012, sem a intenção de avaliar a indústria, mas para mostrar como se aplica o modelo de dispersão em casos práticos. Dessa forma, disponibilizar uma metodologia que possa ser usada em estudos que ajudem a tomar decisões de planejamento para a colocação de novas fontes de emissão ou a alteração das antigas. Como resultado, se consegue imagens onde é facilmente reconhecível a área de susceptibilidade das emissões provenientes da fonte fixa, as quais são interpretadas para esclarecer o que poderia acontecer frente aos diversos cenários possíveis.
395

Reatividade fotoquímica da atmosfera de Cubatão e a influência de fontes exógenas / Silva, M. F. Photochemical reactivity of the atmosphere of Cubatão and the influence of exogenous pollutants: 2012

Moacir Ferreira da Silva 11 March 2013 (has links)
Objetivo. Demonstrar que a ocorrência de episódios críticos de poluição por ozônio na região de Cubatão-Centro é influenciada pelo aporte externo de poluentes, que participam dos processos físico-químicos de formação e remoção de reagentes fotoquímicos na atmosfera. Métodos. O estudo envolveu a obtenção e o tratamento de dados meteorológicos e de concentrações de poluentes fornecidos pela rede de monitoramento da qualidade do ar, bem como a realização de campanhas de amostragem passiva de ozônio (O ) e ativa de COVs, aldeídos e etanol na atmosfera da região. A amostragem de O VI 3 foi realizada com amostradores tipo Ogawa® e as concentrações foram determinadas por cromatografia iônica, com detecção por condutividade elétrica. Na amostragem de COVs foram utilizados tubos de aço contendo o adsorvente Tenax-GR, e a quantificação das amostras foi realizada por cromatografia gasosa e espectrometria de massas. A amostragem de aldeídos foi realizada com cartuchos de sílica gel revestido com 2,4 DNPH, e a quantificação realizada por cromatografia liquida de alta performance, com detector ultravioleta (UV/VIS). A amostragem de etanol foi realizada com cartuchos revestidos de florisil, e a quantificação realizada por flame ionization detector. O transporte de massas de ar foi analisado com base em backward trajectories, calculadas pelo modelo STILT. A interpretação dos dados foi realizada por estatística descritiva, boxplot, análise de correlação e análise multivariada (clusters). Resultados. A maioria dos episódios de ultrapassagem do PQAr de ozônio ocorreu no verão, entre 15h e 16h, com ventos predominantes de S/SE e velocidades superiores a 2,5m/s, típicos de períodos diurnos (brisa marítima). As espécies orgânicas precursoras de ozônio mais importantes foram: formaldeído, acetaldeído, tolueno, 1,2,3-trimetilbenzeno, m-xileno, etanol, oxileno, etilbenzeno, 1,3,5-trimetilbenzeno e benzeno. A retrotrajetória das massas de ar que chegam à Cubatão-Centro comprovou a influência de emissões exógenas. Os resultados obtidos na circulação de mesoescala, simulada pelo modelo BRAMS, concordam com os resultados obtidos por JAESCHKE (1997), onde apenas uma parcela da concentração média de poluentes de Cubatão-Centro era oriunda de fontes locais, sendo o restante decorrente do transporte de massas, com ocorrência de elevadas concentrações de poluentes com fluxo de direção norte-noedeste (brisa terrestre) e sul-sudeste (brisa marítima) / Objective. Demonstrate that critical episode occurrences of air pollution are influenced by external input of pollutants that participate in the processes of atmospheric photochemical reagent formation and removal. Methods. The study involved meteorological data collection and processing of pollutant concentration data gathered by the air quality monitoring network. Campaigns of passive sampling of O and active sampling of VOCs, aldehydes and ethanol in the atmosphere of the region were also performed. The O 3 sampling was conducted with the Ogawa ® type samplers and the concentrations were determined by ion chromatography with electrical conductivity detector. VOCs sampling was performed using steel tubes containing Tenax GR adsorbent, and quantification was done by gas chromatography and mass spectrometry. Aldehyde sampling was performed with silica gel cartridges coated with 2,4 DNPH and quantification done by High Performance Liquid Chromatography (HPLC) with ultraviolet detector (UV / VIS). Ethanol sampling was performed with florisil coated cartridges and quantification by flame ionization detector. The transport of air masses was analyzed based on Backward trajectories calculated by the model STILT. Interpretation of the data was performed using descriptive statistics, boxplots, correlation analysis and multivariate analysis (clusters). Results. Most episodes of Ozone exceeding Air Quality Standards occurred in the summer, between 15h and 16h, with prevailing winds from S / SE and with velocities greater than 2.5 ms -1 , typical of day periods (sea breeze). Major ozone precursor organic species are: formaldehyde, acetaldehyde, toluene, 1,2,3-trimethylbenzene, m-xylene, ethanol, xylene, ethylbenzene, 1,3,5trimethylbenzene and benzene. The retro trajectory of air masses arriving at Cubatão-Center proved the influence of exogenous emissions. Results in the mesoscale circulation given by model simulation by BRAMS, agree with the results obtained by JAESCHKE (1997), showing that only a portion of the average concentration of pollutants Cubatão-Centro was due to local sources, with the rest resulting from the transport of masses, with the occurrence of high concentrations of pollutants resulting when flow directions are from NW (land breeze) and SE (sea breeze).
396

Distribuição espacial do ozônio troposférico em Jundiaí - SP, como subsídio a estudos de exposição da população / Spatial distribution of tropospheric ozone in Jundiaí - SP, as a subsidy to population exposure studies

Edson Pacheco Júnior 20 June 2018 (has links)
O monitoramento dos poluentes atmosféricos é um dos principais itens para a gestão do ar em centros urbanos e rurais atualmente. Entretanto, os altos custos de infraestrutura e de manutenção das estações de monitoramento da qualidade do ar inviabilizam muitos países, estados e municípios de implementarem esse intrumento. No Brasil, a gestão da qualidade do ar é restrita a alguns estados. No caso do monitoramento da qualidade do ar, a medida é restrita a algumas cidades. A fim de contribuir com o entendimento dos níveis de ozônio em uma cidade do interior paulista, foram conduzidas vinte e seis campanhas de amostragem semanal do ozônio tropósférico entre setembro de 2016 e setembro de 2017, em Jundiaí. Foram investigadas algumas características que são determinantes para a ocorrência do poluente ao longo das quatro estações e a variação em sete bairros do município. Com o propósito de avaliar o desempenho dos amostradores passivo frente as medições do monitor automático da CETESB, um dos locais selecionados foi a estação de monitoramento da CETESB. Em relação aos sete bairros, contatou-se diferença estatística (p<0,05) através da aplicação da Análise de Variância (ANOVA), sendo constatada diferença em um local do município com o teste de Dunnett. Nas amostras coletadas na estação da CETESB, observou-se correlação da temperatura e a umidade relativa do ar com o ozônio. Essas variáveis inseridas em um modelo de regressão com as amostragens passivas resultou na explicação de 92% (r2=0,921) das medições realizadas pelo monitor automático da CETESB. Por meio da análise das retrotrajetórias de parcelas de ar foi possível verificar que as concentrações de ozônio em Jundiaí possivelmente sejam influenciadas pelas emissões de outras regiões. Além disso, propôs-se contribuir com o desenvolvimento de novas técnicas de monitoramento de ozônio, montando e validando preliminarmente um dispositivo de baixo custo com um sensor programado no hardware Arduino. Foi feita a calibração indireta do dispositivo de medição de ozônio com o monitor automático da CETESB. Observou-se que os resultados obtidos pelo dispositivo não apresentaram correlação com os do monitor da CETESB (p>0,05), ainda que o primeiro e segundo quartis tenham apresentado correlação (p<0,05). O dispositivo precisa ser mais bem avaliado com calibração em laboratório. / Monitoring of air pollutants is one the main items for air management in urban and rural centers today. However, the high costs of infrastructure and maintenance of air quality monitoring stations manke many countries, states and municipalities unable to implement this instrument. In Brazil air quality management is restrict to some states. In the case of air quality monitoring, the measure is restricted to some cities. In order to contribuite to the understanding of ozone levels in a city in the state of São Paulo, twenty-six weekly sampling campaigns of tropospheric ozone between September 2016 and Sptember 2017 in Jundiaí. It was investigated some characteristics that are determinant for the occurance of the pollutant throughout the four seasons and the variation in seven districts os the Jundiaí. In order to evaluate the performance of the passive samplers against the CETESB automatic monitor measurements, one of the selected sites was the monitoring station of CETESB. About the seven neighborhoods, a statistical difference (p<0.05) was applied through the Analysis of Variace (ANOVA), and a difference was found in one locality of the municipality with the Dunnett test. In the samples collected at the CETESB station, a correlation was observed between temperature and air humidity and ozone. These variables inserted in a regression model with the passive samplings resulted in the explanation of 92% (r²=0.921) of the measurements performed by the CETESB automatic monitor. By analyzing the backward trajectories of air parcels, it was possible to verify that ozone concentrations in Jundiaí are possibly influenced by emissions from other regions. In addition, it was proposed to contribute to the development of new ozone monitoring techniques by assembling and preliminarily validating a low-cost device with a sensor programmed into Arduino hardware. The indirect calibration of the ozone measuring device was done with the CETESB automatic monitor. It was observed that the results obtained by the device did not correlate with those of the CETESB monitor (p>0.05), although the first and second quartiles showed a correlation (p<0.05). The device needs to be better evaluated with laboratory calibration.
397

Avaliação da qualidade ambiental interna no transporte coletivo da cidade de São Carlos, SP / Assessment of indoor environmental quality in public transport from the city of São Carlos, SP

Fernanda Santana Peiter 12 May 2014 (has links)
A circulação no trânsito das cidades faz parte da rotina das pessoas, que podem despender tempos consideráveis dentro de automóveis durante seus deslocamentos. Fatores como a emissão de gases provinda do tráfego e a má circulação de ar podem afetar a qualidade ambiental no interior dos veículos e torná-lo prejudicial à saúde de seus ocupantes. Sendo assim, durante vinte dias aleatórios, entre agosto e dezembro de 2013, monitorou-se o ambiente interno de um dos ônibus pertencentes ao sistema de transporte coletivo da cidade de São Carlos. Foram medidos temperatura, umidade relativa do ar, ruído, monóxido e dióxido de carbono, compostos orgânicos voláteis totais (COVT) e material particulado. Os dados encontrados foram analisados baseando-se em distintas normas e padrões. Observou-se também a influência dos parâmetros avaliados na saúde das pessoas, de acordo com a literatura. Dentre as referências consultadas, consideraram-se os valores limites recomendados pelo Ministério do Trabalho e Emprego (normas NR-15, NR-17 e NHO 01), pela Agência Nacional de Vigilância Sanitária (Resolução 09/03), pelo Conselho Nacional de Meio Ambiente (Resolução 03/90) e pela Organização Mundial de Saúde. A partir dos dados de temperatura e umidade relativa do ar, calculou-se o índice de calor (Heat Index) utilizado pela National Oceanic and Atmospheric Administration dos EUA, para averiguação do conforto térmico. Os resultados mostraram que os níveis de temperatura, umidade relativa, índice de calor e material particulado estiveram, em sua maioria, acima dos valores referenciais. O ruído também constitui um fator preocupante, apesar de os valores encontrados estarem abaixo do limite máximo de 85 dB(A), pois, pesquisas recentes indicam que níveis acima de 60 dB(A) tendem trazer complicações à saúde (Willich et al., 2006). Ao observar as concentrações dos óxidos de carbono, notou-se a interferência da poluição provinda do meio externo. Por fim, conclui-se que a qualidade ambiental interna do ônibus pode ser prejudicial principalmente aos cobradores e motoristas, que trabalham neste ambiente por muitas horas diárias. / The movement of traffic in cities is part of the people\'s routine that can spend considerable time inside automobiles during their displacement. Factors such as greenhouse gas emissions from traffic and poor air circulation can affect the environmental quality inside vehicles and make it harmful to the health of its occupants. Thus, for twenty random days between August and December 2013, air quality inside one of the buses belonging to the public transportation system of the city of São Carlos was monitored. Temperature, relative humidity, noise, carbon monoxide, carbon dioxide, volatile organic compounds (TVOC) and particulate matter were measured. Data were analyzed based on limiting values recommended by different institutions and observing the influence of the parameters measured in people\'s health, according to the literature. Were taken as reference standards established by the Ministry of Labor and Employment (standards NR-15, NR-17 and NHO 01), the National Health Surveillance Agency (Resolution 09/03), the National Environmental Council (Resolution 03 / 90) and the World Health Organization. Aiming to verify the thermal sensation, we calculated the Heat Index used by the National Oceanic and Atmospheric Administration of the USA. The results show that levels of temperature, relative humidity, heat index and particulate matter are mostly above the reference values. Noise is also a worrying factor, despite being within the ceiling of 85 dB (A), because, according to recent surveys, over 60 dB (A) there is potential damage to health (Willich et al., 2006). By observing the concentrations of oxides of carbon, it was noted interference stemmed from the pollution of the external environment. Finally, it is concluded that the air quality inside the bus can be harmful especially to collectors and drivers, working in this environment for many hours a day.
398

Bioremediation of roadside pollutants NO₂ and benzene by integrating angiosperm Wedelia trilobata and spent compost of basidiomycete Pleurotus pulmonarius.

January 2011 (has links)
Lee, Ching Yuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 275-288). / Abstracts in English and Chinese. / List of Figures --- p.vii / List of Tables --- p.xv / List of Abbreviations and Symbols Used --- p.xix / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Roadside Air Pollution Problem --- p.1 / Chapter 1.1.1 --- Nitrogen Dioxide --- p.9 / Chapter 1.1.2 --- Benzene --- p.12 / Chapter 1.1.3 --- Heat and Noise --- p.13 / Chapter 1.2 --- Treatment Methods for Removal of Ambient Air Pollutants --- p.15 / Chapter 1.2.1 --- Physical and Chemical Methods --- p.15 / Chapter 1.2.2 --- Bioremediation --- p.17 / Chapter 1.2.3 --- Passive System and Active System --- p.18 / Chapter 1.3 --- Research Strategy --- p.18 / Chapter 1.3.1 --- Plant as a Bioremediating Agent --- p.18 / Chapter 1.3.2 --- Spent Mushroom Compost (SMC) as a Bioremediating Agent --- p.20 / Chapter 1.3.3 --- An Integrated System for Air Bioremediation --- p.24 / Chapter 1.3.4 --- Aim and Objectives of the Project --- p.24 / Chapter 1.4 --- Significance of the Project --- p.25 / Chapter 2. --- Materials and Methods --- p.26 / Chapter 2.1 --- Source of Materials --- p.28 / Chapter 2.1.1 --- Ingredients of Plant Growth Substrate --- p.28 / Chapter 2.1.2 --- Plants --- p.30 / Chapter 2.2 --- Formulation of the Plant Substrate --- p.31 / Chapter 2.2.1 --- Water Holding Capacity --- p.31 / Chapter 2.2.2 --- Water Retention --- p.32 / Chapter 2.2.3 --- Seed Germination Toxicity and Tissue Elongation --- p.33 / Chapter 2.2.4 --- Bulk Density and Porosity --- p.34 / Chapter 2.2.5 --- Substrate Shrinkage --- p.35 / Chapter 2.3 --- Characterization of the Materials --- p.36 / Chapter 2.3.1 --- pH --- p.36 / Chapter 2.3.2 --- Electrical Conductivity --- p.36 / Chapter 2.3.3 --- % Organic Matter --- p.37 / Chapter 2.3.4 --- "Nutrient Contents (Nitrogen, Phosphorus, Potassium, Magnesium, Calcium, Sodium, Iron)" --- p.37 / Chapter 2.3.5 --- Total Organic Carbon --- p.40 / Chapter 2.3.6 --- Detection for Heavy Metal Contaminants --- p.40 / Chapter 2.3.7 --- Detection for Organic Contaminants --- p.41 / Chapter 2.3.8 --- Extraction Efficiency of Heavy Metal Content and Organic Contaminants --- p.43 / Chapter 2.3.9 --- Outdoor Growing Trial of the Bioremediation System using Various Plant Species --- p.45 / Chapter 2.4 --- Characterization of the Plant --- p.47 / Chapter 2.4.1 --- Leaf Area Estimation --- p.47 / Chapter 2.4.2 --- Density of Plantlet --- p.48 / Chapter 2.4.3 --- Growth Rate of Plantlet in Water --- p.49 / Chapter 2.5 --- Temperature Stabilization Test --- p.50 / Chapter 2.6 --- NO2 Removal Test --- p.52 / Chapter 2.6.1 --- Preparation of Plantlets --- p.52 / Chapter 2.6.2 --- Generation and Sampling of NO2 --- p.52 / Chapter 2.6.3 --- Effect of N02 Concentration on RE --- p.55 / Chapter 2.6.4 --- Effect of Various Combinations in the Bioremediation System --- p.56 / Chapter 2.6.5 --- "Comparison to Photocatalytic Paint, Physical Sorbents and Other Planting Media" --- p.57 / Chapter 2.6.6 --- Effect of Temperature --- p.60 / Chapter 2.6.7 --- Effect of Retention Time --- p.61 / Chapter 2.6.8 --- Effect of Exposed Time --- p.61 / Chapter 2.6.9 --- Composition Analysis --- p.62 / Chapter 2.6.10 --- Post Tests after N02 Removal Test --- p.63 / Chapter 2.6.11 --- Chlorophyll and Carotenoid Contents --- p.63 / Chapter 2.6.12 --- Phenolic Content --- p.64 / Chapter 2.6.13 --- Total Microbial Count --- p.65 / Chapter 2.6.14 --- Activities of Antioxidative Enzymes --- p.66 / Chapter 2.6.15 --- Nitrite Oxidizing Enzyme --- p.68 / Chapter 2.7 --- Benzene Removal Test --- p.69 / Chapter 2.7.1 --- Preparation of Plantlets --- p.69 / Chapter 2.7.2 --- Generation and Sampling of Benzene --- p.69 / Chapter 2.7.3 --- Effect of Benzene Concentration on RE --- p.74 / Chapter 2.7.4 --- Effect of Various Combinations in the Bioremediation System --- p.75 / Chapter 2.7.5 --- Effect of Temperature --- p.76 / Chapter 2.7.6 --- Effect of Exposed Time --- p.77 / Chapter 2.7.7 --- Effect of Retention Time --- p.78 / Chapter 2.7.8 --- Composition Analysis --- p.78 / Chapter 2.7.9 --- "Comparison to Physical Sorbents, Photocatalytic Paint and Other Planting Media" --- p.79 / Chapter 2.7.10 --- Trials in Order to Increase RE of Benzene --- p.80 / Chapter 2.7.11 --- Residual Benzene in Substrate --- p.83 / Chapter 2.7.12 --- Post Tests after Benzene Removal Test --- p.84 / Chapter 2.7.13 --- Catechol Oxidase Activity --- p.85 / Chapter 2.8 --- Removal Tests for Other Air Pollutants --- p.86 / Chapter 2.9 --- Field Study --- p.88 / Chapter 2.10 --- Statistical Analysis --- p.98 / Chapter 3. --- Results --- p.99 / Chapter 3.1 --- Formulation of Plant Substrate --- p.99 / Chapter 3.1.1 --- Dose of SMC in Substrate Formula --- p.99 / Chapter 3.1.2 --- Dose of SAP in Substrate Formula --- p.105 / Chapter 3.1.3 --- Dose of Rice Hull in Substrate Formula --- p.111 / Chapter 3.2 --- Characterization of the Optimized Wedelia- growing Substrate --- p.118 / Chapter 3.2.1 --- Physical and Chemical Analysis --- p.118 / Chapter 3.2.2 --- Nutrient and Metal Contents --- p.120 / Chapter 3.2.3 --- Detection of Heavy Metal Contaminants --- p.124 / Chapter 3.2.4 --- Detection for Organic Contaminants --- p.126 / Chapter 3.3 --- Outdoor Growing Trial of Various Plants --- p.138 / Chapter 3.4 --- Plant Characterization --- p.143 / Chapter 3.4.1 --- Growth Rate of Plantlets in Water --- p.143 / Chapter 3.5 --- Temperature Stabilization Test --- p.146 / Chapter 3.6 --- NO2 Removal Test --- p.149 / Chapter 3.6.1 --- Effect of NO2 Concentration on RE --- p.149 / Chapter 3.6.2 --- Effect of Various Combinations in the Bioremediation System --- p.156 / Chapter 3.6.3 --- "Comparison to Photocatalytic Paint, Physical Sorbents and Other Planting Media" --- p.160 / Chapter 3.6.4 --- Effect of Temperature --- p.164 / Chapter 3.6.5 --- Effect of Retention Time --- p.166 / Chapter 3.6.6 --- Effect of Exposed Time --- p.168 / Chapter 3.6.7 --- Post Test Results After Various Exposed Times --- p.170 / Chapter 3.6.8 --- Microbial Count After Various Exposed Times --- p.176 / Chapter 3.6.9 --- Contribution of the Components of the Bioremediation System to Remove NO2 --- p.178 / Chapter 3.7 --- Benzene Removal Test --- p.183 / Chapter 3.7.1 --- Effect of Benzene Concentration on RE --- p.183 / Chapter 3.7.2 --- Effect of Various Combinations in the Bioremediation System --- p.186 / Chapter 3.7.3 --- Effect of Temperature --- p.190 / Chapter 3.7.4 --- Effect of Retention Time --- p.192 / Chapter 3.7.5 --- Effect of Exposed Time --- p.194 / Chapter 3.7.6 --- Contribution of Components of the Bioremediation System to Remove Benzene --- p.198 / Chapter 3.7.7 --- Optimization of the Benzene Removal of the Bioremediation System --- p.200 / Chapter 3.7.8 --- "Comparison to Photocatalytic Paint Coatings, Physical Sorbents and Other Planting Media" --- p.204 / Chapter 3.8 --- Removal Test for Other Air Pollutants --- p.208 / Chapter 3.9 --- Field Study I --- p.210 / Chapter 3.9.1 --- Environmental Parameters --- p.210 / Chapter 3.9.2 --- Noise --- p.212 / Chapter 3.9.3 --- Removal versus Distance --- p.213 / Chapter 3.9.4 --- Barrier Effect by Canvas --- p.216 / Chapter 3.9.5 --- NO2 Concentration --- p.216 / Chapter 3.9.6 --- VOC Concentration --- p.218 / Chapter 3.10 --- Field Study II --- p.220 / Chapter 3.10.1 --- Environmental Parameters --- p.220 / Chapter 3.10.2 --- Noise --- p.222 / Chapter 3.10.3 --- NO2 Concentration --- p.224 / Chapter 3.10.4 --- VOC Concentration --- p.225 / Chapter 4. --- Discussion --- p.228 / Chapter 4.1 --- Formulation of a Plant-growing Substrate --- p.228 / Chapter 4.2 --- Temperature Stabilization --- p.231 / Chapter 4.3 --- Dynamic Flow Through System in Pollutant Removal Experiment --- p.233 / Chapter 4.4 --- N02 Removal Test --- p.237 / Chapter 4.4.1 --- Limiting Factors of NO2 Removal --- p.237 / Chapter 4.4.2 --- Adsorption Isotherm --- p.239 / Chapter 4.4.3 --- Contribution of NO2 Removal by Various Components --- p.241 / Chapter 4.4.4 --- Comparison of NO2 Removal with Other Systems --- p.242 / Chapter 4.4.5 --- Comparison of NO2 Removal with Other Studies --- p.246 / Chapter 4.4.6 --- Toxicity of NO2 towards the Bioremediation System --- p.247 / Chapter 4.5 --- Interpretation of Results in Benzene Removal Test --- p.251 / Chapter 4.5.1 --- Limiting Factors of Benzene Removal --- p.251 / Chapter 4.5.2 --- Adsorption Isotherm --- p.253 / Chapter 4.5.3 --- Contribution of Benzene Removal by Various Components --- p.254 / Chapter 4.5.4 --- Comparison of Benzene Removal with Other Systems --- p.255 / Chapter 4.5.5 --- Trials in Order to Increase RE of Benzene --- p.256 / Chapter 4.5.6. --- Comparison of Benzene Removal with Other Studies --- p.258 / Chapter 4.6 --- Removal of Other Air Pollutants --- p.261 / Chapter 4.7 --- Field Studies with the Vertical Panels of the Bioremediation System --- p.264 / Chapter 4.7.1 --- Barrier Effect by Canvas --- p.264 / Chapter 4.7.2 --- Temperature Buffering --- p.265 / Chapter 4.7.3 --- Sound Attenuation --- p.266 / Chapter 4.7.4 --- NO2 and VOC Removal --- p.268 / Chapter 5. --- Conclusion --- p.272 / Chapter 6. --- Further Investigation --- p.274 / Chapter 7. --- References --- p.275
399

Cobenefits of Global and Domestic Greenhouse Gas Emissions for Air Quality and Human Health

West, Jason, Zhang, Yuqiang, Smith, Steven, Silva, Raquel, Bowden, Jared, Naik, Vaishali, Li, Ying, Gilfillan, Dennis, Adelman, Zachariah, Fry, Meredith, Anenberg, Susan, Horowitz, Larry, Lamarque, Jean-Francois 01 April 2017 (has links)
Abstract available in the Lancet.
400

Co-Benefits of Global and Domestic Greenhouse Gas Emissions for Air Quality and Human Health

West, Jason, Zhang, Yuquiang, Smith, Steven, Silva, Raquel, Bowden, Jared, Naik, Vaishali, Li, Ying, Gilfillan, Dennis, Adelman, Zachariah, Fry, Meredith, Anenberg, Susan, Horowitz, Larry, Lamarque, Jean-Francois 01 October 2017 (has links)
No description available.

Page generated in 0.5567 seconds