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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.
181

The social geography of industrial pollution in the metropolitan area of Buenos Aires

Ramírez Cuesta, Alejandra Elisa 25 February 2013 (has links)
The purpose of this study is to investigate the driving factors of population exposure to sources of environmental pollution and to determine if poor neighborhoods are disproportionately exposed to negative environmental externalities. This research also examines whether the concentration of polluting industries within neighborhoods of different socio-economic levels varies over time. To determine the causes of the spatial coincidence between population and industrial polluters, this study employs a mixed-methods approach. Quantitatively, this study uses an exploratory approach to capture the effects of poverty and segregation on the density of hazardous industries. This methodological approach models the spatial variation of the relationship between poverty and pollution. Qualitatively, a cross-case comparative analysis is conducted on two different socio-economic neighborhoods to trace the causes of continuity or change in industrial density. The study finds that polluting industries tend to be distributed homogenously across neighborhoods of different socio-economic backgrounds and that poverty and segregation are not mayor drivers of that distribution. On the contrary, the relationship between poor and segregated and industries presents spatial variation and it is localized in some specific areas. The case-studies comparison, moreover, indicates that the spatial concentration of hazardous industries varies over time, decreasing slightly in a middle-class neighborhood and increasing in a poor neighborhood. This is explained by: i) economic constraints and opportunities to the local economy determine the permanence of polluting activities; ii) middle-class collective actions to live in a better environment contribute to expel polluting activities from the neighborhood in the long run; and iii), local political practices and the lack of alternatives and resources to access the formal land market means that the poor face tremendous environmental burdens which traps them in a noxious environment. Several policy implications arise from this research; first, access to information, transparency, and environmental law enforcement must be strengthened in order to underpin equity and common standards across the city. Second, local governments should weigh and balance the need for housing and development, and the environmental consequences when establishing zoning ordinances. Third, policies and resources should be targeted towards residents, especially those poorer residents that are most at risk. / text
182

Evaluation of Toxic Release Inventory Facilities in Metropolitan Atlanta: Census Tract Demographics, Facility Distribution, Air Toxic Emissions and Regulation

Johnson, Ryan 15 May 2015 (has links)
Background and Purpose Low socioeconomic status (SES) populations as well as minorities are often exposed to a disproportionate number of hazardous chemical including hydrogen fluoride, benzene and formaldehyde (Bullard, 2008). The sources of these hazards may include noxious land uses such as incinerators and landfills, Superfund sites, Toxic Release Inventory (TRI) facilities, sewer and water treatment plants, and other locally unwanted land uses (Choi, Shim, Kaye, & Ryan, 2006). The disproportionate burden often results in increased exposure to harmful environmental conditions for affected communities (Wilson et al., 2014). The objectives of this study are to evaluate the relevance of demographic characteristics to (1) TRI facility location, (2) TRI chemical emissions, and (3) incidence and resolution of facility complaints. Methods The study area is the Atlanta Metropolitan Statistical Area (MSA), designated by the United States Office of Management and Budget is comprised of 20 counties. Multivariate logistic regression was used to assess the relative importance of race and socioeconomic variables in predicting whether a TRI facility was located in a census tract. We applied multiple regression models to examine the association between amount of air toxics released from TRI facilities in the census tract (dependent variable), the number of emissions from TRI facilities in the census tract and the amount of chemicals released per emission and socio-demographic variables at the census tract level. Additionally, multivariate ordinal logistic regression was used to evaluate the association between the number of complaints to toxic chemicals and time to resolution of complaints and the covariates (SES and race/ethnicity) at the census tract level. Results In multivariate models the odds ratio for the presence of a TRI facility is 0.89 (p=0.002) for each 1% increase of females with a college degree and 2.4 (p Discussion and Conclusion We found evidence of racial and socio-demographic disparities in the burden of TRI facilities and chemical emissions in the Atlanta MSA. We observed a trend for toxic chemicals emitted suggesting that more blacks and Hispanics were burdened by and potentially exposed to TRI facilities than were Whites. There was only one predictor, percentage of females with a college degree, where we observed an inverse and statistically significant association with the amount of chemical emissions in pounds. We also found evidence that of potential differences in regulation processes of TRI facilities. Overall, results indicate that race/ethnicity and socioeconomic composition play a role in TRI facility siting and TRI facility emissions indicating burden disparities for low-SES populations as well as non-Whites in the Atlanta MSA. These results are similar to results presented in the environmental justice literature.
183

Investigation Of Non-methane Volatile Organic Carbon Emissions From Interior Materials Used In The Intercity Buses

Gormez, Baran 01 September 2004 (has links) (PDF)
The objectives of this study are to determine the non-methane volatile organic carbon emissions from the parts used in the interiors of buses at different temperatures and to analyze the components of these emissions. The total non-methane volatile organic carbon (NMVOC) concentrations in various sections of a bus were measured in order to determine the indoor air pollution in the bus. Different samples of the materials used in the interior parts of the buses were provided by the manufacturing company and they were tested in the METU Air Pollution Laboratory in order to see what hydrocarbon components make up this total NMVOC concentration.The results of experiments showed that the leading constituent emitted from the test pieces was toluene. Benzene concentration was very low. This is very important since benzene is a carcinogen and it has very low indoor concentration limits determined by OSHA and NIOSH. When the concentrations of the total NMVOC emitted from various parts are examined, it was seen that the most of the VOC emissions occur from the floor materials and ventilation channel. After measurements were done in two buses the average indoor total NMVOC concentrations were found as 21.15 &plusmn / 5.8 ppmv (as C3H8) and 46.04 &plusmn / 9.2 ppmv (as C3H8) in the first and second bus, respectively. Suggestions were made to the manufacturing company for some replacement of solvents and adhesives, and measurements were repeated with the newly manufactured parts for the bus. The highest concentrations were observed for toluene in these measurements, too. However, the toluene concentration was at least 40% lower than the initial values. Benzene concentrations were again very low. The average indoor total NMVOC concentrations were found as 10.41 &plusmn / 2 ppmv (as C3H8) in the measurements done in the bus decorated with new materials. This concentration was about 50% and 25% of the values measured in the first and the second bus at the beginning of the study, respectively.
184

Investigation Of Emission Factors Of Non-methane Hydrocarbons For Some Widely Used Passenger Cars In Turkey

Onoglu, Irem 01 September 2004 (has links) (PDF)
The objectives of this study are to measure the non-methane volatile organic carbon (NMVOC&#039 / s) emissions from passenger cars in Turkey having gasoline engines, to determine emission factors of these vehicles for BTEX compounds and comparison of emission factors obtained in this study with the emission factors of the other countries. This study was conducted in two parts: The first part was to determine the categories of passenger cars widely used in Turkey, and also to determine the average carbon monoxide (CO) and hydrocarbon (HC) emissions at idle condition for these car types based on the exhaust emission measurements of Ankara &Ccedil / evre Koruma Vakfi (AN&Ccedil / EVA). The second part of the study was to analyze the gas composition of exhaust gasses at different road conditions for BTEX components by using gas chromatography. The results of the study have shown that the cars named under &lsquo / &lsquo / Tofas&rsquo / &rsquo / constitute 31.5% and &lsquo / &lsquo / Fiat&rsquo / &rsquo / 13.1% of the total cars in Turkey and they are manufactured by the same company. Therefore, studies have been performed with &lsquo / &lsquo / Tofas/Fiat&rsquo / &rsquo / cars. The highest emission factors among hydrocarbons investigated in this study were found for toluene and m-xylene. Generally, as driving speed increases the emissions of HC&rsquo / s are found to decrease in concentration. It was interesting to note that the highest emissions occur at 30 km/hr speed which is the mostly used speed in crowded streets and busy intersections. Therefore, it was concluded that it is very important to take measures for emissions in the city traffic. Cold start emissions were also found to be higher than the hot start emissions.
185

Combustion And Co-combustion Of Olive Cake And Coal In A Fluidized Bed

Varol, Murat 01 June 2006 (has links) (PDF)
In this study, combustion performances and emission characteristics of olive cake and olive cake+coal mixture are investigated in a bubbling fluidized bed of 102 mm inside diameter and 900 mm height. The average particle sizes of coal and olive cake used in the experiments were 1.57 mm and 1.52 mm, respectively. Flue gas concentrations of O2, CO, SO2, NOx, and total hydrocarbons (CmHn) were measured during combustion experiments. Operational parameters (excess air ratio, secondary air injection) were changed and variation of pollutant concentrations and combustion efficiency with these operational parameters were studied. The temperature profiles measured along the combustor column was found higher in the freeboard for olive cake than coal due to combustion of hydrocarbons mostly in the freeboard. The location of the maximum temperature in the freeboard shifted to the upper part of the column, as the volatile matter content in the fuel mixture increased. Combustion efficiencies in the range of 83.6-90.1% were obtained for olive cake with the excess air ratio of 1.12-2.30. The corresponding combustion efficiency for coal was 98.4-99.7% under the same conditions. As the CO and hydrocarbon concentration in the flue gas increased, the combustion efficiency decreased. Also co-combustion experiments of olive cake and coal for various mixing ratios were carried out. As the amount of olive cake in the fuel mixture increased, SO2 emissions decreased because of the very low sulfur content of olive cake. In order to increase the combustion efficiency, secondary air was injected into the freeboard which was a good solution to decrease the CO and hydrocarbon emissions, and to increase the combustion efficiency. For the setup used in this study, the optimum operating conditions with respect to NOx and SO2 emissions were found as 1.35 for excess air ratio, and 30 L/min for secondary air flowrate for the combustion of 75 wt% olive cake and 25 wt% coal mixture. Highest combustion efficiency of 99.8% was obtained with an excess air ratio of 1.7, secondary air flow rate of 40 L/min for the combustion of 25 wt% olive cake and 75 wt% coal mixture.
186

An investigation into the efficacy of eggshells as a low cost adsorbent for the removal of potentially toxic inorganic elements from aqueous solutions

Mashangwa, Terence Dambudzo 09 1900 (has links)
Excessive release of metals and metalloids into the environment is a major global environmental concern and there is need for environmentally friendly and cost effective methods for their removal. The present study investigated the adsorptive removal of zinc, lead, copper and nickel ions from synthetic aqueous solutions and various metals from three acid mine drainage (AMD) sites using chicken eggshells. Process parameters including the initial metal concentration were evaluated and the optimum conditions obtained were pH 7, adsorbent dose of 7 g and contact time of 360 minutes (for the removal of 100ppm metal ions). Under these conditions the percentage adsorptions were; 97% for lead, 95% for copper, 94% for nickel and 80% for zinc. Aluminium, iron, potassium, nickel and zinc ions all had percentage adsorptions above 75% in AMD Sample 1. Potassium had a 98.78% adsorption while magnesium, strontium and zinc had 72.33; 68.75 and 53.07% adsorption respectively in Sample 2. Arsenic, chromium, copper, iron, antimony and tellurium ions were above 75% for Sample 3. The study demonstrated the efficacy of chicken eggshells and presents it as a viable low-cost adsorbent for bioremediation. / Environmental Science / M. Sc. (Environmental Science)
187

Estudo e caracterização de compósito de polipropileno e pó de pneu para utilização na indústria automotiva

Lixandrão, Kelly Cristina de Lira January 2017 (has links)
Orientador: Prof. Dr. Fabio Furlan Ferreira / Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Nanociências e Materiais Avançados, 2017. / Em função do constante aumento da populacao e do aumento da producao de veiculos ao longo dos anos, a quantidade de residuos solidos gerados e depositados no meio ambiente cresceu de forma consideravel. O pneu, que e um destes materiais, quando descartado em local inadequado pode provocar serios problemas ambientais e a saude da populacao. Assim no intuito de diminuir sua quantidade enviada ao meio-ambiente e de produzir um ciclo de producao adequado, o po de borracha de pneu foi utilizado como reforco em matriz de polipropileno para ser aplicado no encapsulamento do motor de veiculos comerciais. A sua utilizacao visa assegurar uma reducao do peso da peca e, consequentemente, do veiculo, otimizando seu consumo de combustivel e diminuindo a emissao de poluentes, alem de garantir uma minimizacao da poluicao sonora, atraves da atenuacao do ruido pelo composito. As analises acusticas de perda de transmissao e de ruido externo foram realizadas para verificar se o material atendeu aos limites especificados pelas resolucoes. Analise de difracao de raios X viabilizou a identificacao e a quantificacao das diferentes fases que compoem o material, alem de evidenciar a ocorrencia de polimorfismo. Por calorimetria exploratoria diferencial foi possivel verificar o grau de cristalinidade do material e por termogravimetria foi verificado que a decomposicao termica dos compositos ocorreu em dois estagios: o primeiro na faixa de temperatura entre 300 ¿aC e 400 ¿aC e o segundo entre 400 ¿aC e 500 ¿aC. Ensaios de tracao e flexao demonstraram resultados inferiores aos do polimero virgem; todavia, o ensaio de impacto apresentou valores superiores, em funcao da tenacificacao da matriz termoplastica. / Due to the constant increase in population and the increase in vehicle production over the years, the amount of solid waste generated and deposited in the environment has grown considerably. The tire, which is one of these materials, when discarded in inappropriate locations can cause serious environmental problems and to the health of the population. Thus, in order to reduce the amount sent to the environment and to generate an appropriate production cycle, the tire rubber powder was used as reinforcement in a polypropylene matrix to be applied to the engine encapsulation of commercial vehicles. It is intended to provide a reduction of the weight of the piece and thus the vehicle, optimizing fuel consumption and reducing the emission of pollutants; also it ensures the minimization of noise pollution through the noise attenuation by composite. Acoustic analysis of transmission loss and external noise were carried out to verify whether the material complies with the limits specified by the resolutions. X-ray diffraction analysis enabled the identification and quantification of the different phases that comprise the material, besides evidencing the occurrence of polymorphism. By differential scanning calorimetry it was possible to verify the degree of crystallinity of the material and by thermogravimetry it was verified that the thermal decomposition of the composites occurred in two stages: the first in the temperature range between 300 ¿aC and 400 ¿aC and the second one between 400 ¿aC and 500 ¿aC. Tensile and flexural tests showed lower results than the virgin polymer, however, the impact test had higher values, as a function of thermoplasctic matrix tenacity.
188

Determinação das concentrações de resíduos de gases anestésicos e avaliação genômica e de estresse oxidativo em profissionais recém-expostos / Concentration of waste anesthetic gases in operating rooms and assessment of genetic damage and oxidative stress in medical residents

Lucio, Lorena Mendes de Carvalho [UNESP] 25 August 2016 (has links)
Submitted by LORENA MENDES DE CARVALHO LUCIO null (limcarvalho@yahoo.com.br) on 2016-09-12T13:56:26Z No. of bitstreams: 1 TESE FINAL LORENA POS BANCA Repositorio UNESP 12.09.16.pdf: 1673690 bytes, checksum: 578ad77e846c1bc6a83776f9b4d1b8bf (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-09-14T18:44:12Z (GMT) No. of bitstreams: 1 lucio_lmc_dr_bot.pdf: 1673690 bytes, checksum: 578ad77e846c1bc6a83776f9b4d1b8bf (MD5) / Made available in DSpace on 2016-09-14T18:44:12Z (GMT). No. of bitstreams: 1 lucio_lmc_dr_bot.pdf: 1673690 bytes, checksum: 578ad77e846c1bc6a83776f9b4d1b8bf (MD5) Previous issue date: 2016-08-25 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente estudo objetivou determinar as concentrações dos resíduos de gases anestésicos (RGA) em salas de operação (SO) e o impacto dessa exposição ocupacional em relação aos danos genômicos e estresse oxidativo em profissionais recém-expostos. O estudo foi conduzido no Hospital das Clínicas, Faculdade de Medicina de Botucatu-UNESP. As concentrações de isoflurano, sevoflurano e óxido nitroso (N2O) foram medidas nas SO por espectrofotometria infravermelha, com equipamento portátil. Sessenta e três médicos residentes, ao final de três anos do Programa de Residência Médica, foram alocados em dois grupos: exposto (Anestesiologia e Cirurgia, n=32) e controle (Clínica Médica, n=31). Amostras de sangue periférico e células bucais foram coletadas e protegidas da luz. Avaliaram-se danos no material genético (teste do cometa - danos basais, purinas e pirimidinas oxidadas em linfócitos; 8-hidroxi-2’-desoxiguanosina no plasma), micronúcleo (MN) em células bucais, proteínas carboniladas, marcadores de lipoperoxidação (malonaldeído e 4-hidroxinonenal) e capacidade antioxidante plasmática (ferric reducing antioxidant power, oxygen radical absorbance capacity e total antioxidant performance). As concentrações médias dos RGA foram superiores aos limites internacionalmente recomendados (2,7 vezes: isoflurano; 4,9 vezes: sevoflurano; 7,2 vezes: N2O). Os grupos não diferiram quanto aos dados demográficos (p>0,05). Detectou-se aumento significativo de danos basais no DNA (p=0,01) e maior frequência de MN em células bucais (2,3 vezes; p=0,07) no grupo exposto em relação ao grupo controle, mas não houve diferença (p>0,05) entre os grupos em relação a todos os marcadores de estresse oxidativo. Em conclusão, o estudo mostra que médicos residentes expostos a altas concentrações de RGA apresentam aumento significativo de danos sistêmicos no DNA e frequência aumentada de instabilidade genômica (MN bucais), mas não de estresse oxidativo. Portanto, este estudo mostra que jovens profissionais já apresentam alterações genômicas, o que reforça a importância do biomonitoramento e da diminuição da exposição aos RGA. / This study determined the waste anesthetic gases (WAG) in operating rooms (OR) and evaluated the impact of the occupational exposure in genetic damage and oxidative stress in medical residents. The study was performed at “Hospital das Clínicas, Faculdade de Medicina de Botucatu-UNESP”. The concentrations of isoflurane, sevoflurane and nitrous oxide (N2O) were measured in ORs. Sixty-three medical residents completing their three-year Medical Residency Program were recruited for the study and were assigned to two groups: exposed group (n=32) of Anesthesiology and Surgery areas and control group (n=31) of Internal Medicine area. Blood and buccal cells were concomitantly collected from both groups and protected from light to measure genetic instability by buccal micronucleus (MN), basal and oxidized DNA damage (comet assay and 8-hydroxy-2′-deoxyguanosine), biomarkers of protein and lipid oxidation, and three different assays for plasma antioxidant activity. Mean WAG concentrations were above international thresholds (2.7-fold: isoflurane; 4.9-fold: sevoflurane; 7.2-fold: N2O). There was no significant difference between groups regarding demographic data. Basal DNA damage (p=0.01) and buccal MN frequency (by 2.3-fold; p=0.07) were increased in the exposed group compared to the control group. Results showed no significant difference for oxidative stress biomarkers between groups. In conclusion, this study shows that medical residents exposed to high WAG concentrations have increased systemic DNA damage and genomic instability (buccal MN), but not oxidative stress. Thus, these young professionals already have genetic damage in the beginning of their career. Our results reinforce the importance of the biomonitoring and also the adequate measures to decrease ambient air pollution in the OR. / FAPESP: 2013/21130-0 / CNPq: 472453/2013-0 / CAPES/PGCI: 14527-13-8
189

Determinação das concentrações de resíduos de gases anestésicos e avaliação genômica e de estresse oxidativo em profissionais recém-expostos

Lucio, Lorena Mendes de Carvalho January 2016 (has links)
Orientador: Leandro Gobbo Braz / Resumo: O presente estudo objetivou determinar as concentrações dos resíduos de gases anestésicos (RGA) em salas de operação (SO) e o impacto dessa exposição ocupacional em relação aos danos genômicos e estresse oxidativo em profissionais recém-expostos. O estudo foi conduzido no Hospital das Clínicas, Faculdade de Medicina de Botucatu-UNESP. As concentrações de isoflurano, sevoflurano e óxido nitroso (N2O) foram medidas nas SO por espectrofotometria infravermelha, com equipamento portátil. Sessenta e três médicos residentes, ao final de três anos do Programa de Residência Médica, foram alocados em dois grupos: exposto (Anestesiologia e Cirurgia, n=32) e controle (Clínica Médica, n=31). Amostras de sangue periférico e células bucais foram coletadas e protegidas da luz. Avaliaram-se danos no material genético (teste do cometa - danos basais, purinas e pirimidinas oxidadas em linfócitos; 8-hidroxi-2’-desoxiguanosina no plasma), micronúcleo (MN) em células bucais, proteínas carboniladas, marcadores de lipoperoxidação (malonaldeído e 4-hidroxinonenal) e capacidade antioxidante plasmática (ferric reducing antioxidant power, oxygen radical absorbance capacity e total antioxidant performance). As concentrações médias dos RGA foram superiores aos limites internacionalmente recomendados (2,7 vezes: isoflurano; 4,9 vezes: sevoflurano; 7,2 vezes: N2O). Os grupos não diferiram quanto aos dados demográficos (p>0,05). Detectou-se aumento significativo de danos basais no DNA (p=0,01) e maior frequê... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study determined the waste anesthetic gases (WAG) in operating rooms (OR) and evaluated the impact of the occupational exposure in genetic damage and oxidative stress in medical residents. The study was performed at “Hospital das Clínicas, Faculdade de Medicina de Botucatu-UNESP”. The concentrations of isoflurane, sevoflurane and nitrous oxide (N2O) were measured in ORs. Sixty-three medical residents completing their three-year Medical Residency Program were recruited for the study and were assigned to two groups: exposed group (n=32) of Anesthesiology and Surgery areas and control group (n=31) of Internal Medicine area. Blood and buccal cells were concomitantly collected from both groups and protected from light to measure genetic instability by buccal micronucleus (MN), basal and oxidized DNA damage (comet assay and 8-hydroxy-2′-deoxyguanosine), biomarkers of protein and lipid oxidation, and three different assays for plasma antioxidant activity. Mean WAG concentrations were above international thresholds (2.7-fold: isoflurane; 4.9-fold: sevoflurane; 7.2-fold: N2O). There was no significant difference between groups regarding demographic data. Basal DNA damage (p=0.01) and buccal MN frequency (by 2.3-fold; p=0.07) were increased in the exposed group compared to the control group. Results showed no significant difference for oxidative stress biomarkers between groups. In conclusion, this study shows that medical residents exposed to high WAG concentrations have increase... (Complete abstract click electronic access below) / Doutor
190

Utilização da técnica de fluorescência de raios X por dispersão em energia (EDXRF) na avaliação do material particulado em suspensão na cidade de Limeira - SP / Using energy dispersive X ray fluorescence (EDXRF) technique to evaluate the suspended particulate matter from Limeira city, State of São Paulo, Brazil

Liz Mary Bueno de Moraes 31 August 2009 (has links)
O objetivo principal deste trabalho foi avaliar a composição química do material particulado em suspensão na atmosfera na cidade de Limeira/SP, pela técnica de fluorescência de raios X dispersiva em energia (EDXRF). Um amostrador tipo stacker foi utilizado para coletar particulados fino (partículas com diâmetro aerodinâmico entre 2,5 e 10 \'mü\'m) e grosso (partículas maiores que 10 \'mü\'m), utilizando filtros de policarbmüonato de 47 mm de diâmetro e com diâmetros de poro de 0,4 e 8 \'mü\'m, respectivamente. As amostras foram coletadas em 2006 (de janeiro a dezembro), 2008 (de janeiro a abril e de julho a dezembro) e 2009 (de janeiro a março). Na excitação da técnica de EDXRF utilizou-se um tubo de Mo com filtro de Fe (análise sob vácuo) para a determinação dos elementos do Al ao Ca, e com filtro de Zr (análise sob ar atmosférico) para determinação do Sc ao Zn e também do Pb. Para a detecção dos raios X utilizou-se um detector semicondutor de Si(Li) acoplado a um analisador multicanal, com um tempo de aquisição de 300 s. Os espectros de raios X foram interpretados através do programa AXIL e a para a quantificação dos elementos químicos fez-se o uso da metodologia dos parâmetros fundamentais. Realizou-se também microanálises nas amostras utilizando-se um microscópio eletrônico de varredura acoplado a um sistema de fluorescência de raios X por dispersão em energia (SEM/EDS) para a caracterização química e morfológica das partículas coletadas no material particulado em suspensão. Determinou-se também a concentração de negro de fumo (black carbon) utilizando a técnica de reflectância. Embora a amostragem não tenha sido suficiente para indicar a contribuição de cada fonte de emissão, a metodologia de análise de agrupamento possibilitou a identificar duas principais fontes para o material particulado em suspensão: poeira de solo e resíduos de queima de cana-de-açúcar / The main objective of this work was to evaluate the chemical composition of the suspended particulate matter from the atmosphere of the city of Limeira, State of São Paulo, by energy dispersive X-ray fluorescence (EDXRF) technique. A stacker filter sampler was used to collect the fine (particles with aerodynamic diameter between 2.5 and 10 \'mü\'m) and the gross particulates (particles larger than 10 \'mü\'m) employing 47 mm polycarbonate filters, with 0.4 and 8 \'mü\'m pore diameters, respectively. Samples were collected in 2006 (from January to December), 2008 (from January to April and from July to December), and 2009 (from January to March). The EDXRF excitation was carried out using a Mo X-ray tube with Fe filter (analysis under vacuum) to determine elements from Al to Ca, and with Zr filter (analysis under air atmosphere) to determine from Sc to Zn and also Pb. A Si(Li) semiconductor detector coupled to a multichannel analyzer was used for X-ray detection, with 300 s acquisition time. The X-ray spectra were deconvoluted by the AXIL software, and fundamental parameters methodology was adopted for quantification. Samples microanalysis by scanning electron microscope, connected to an energy dispersive X-ray fluorescence system (SEM/EDS) was carried out for chemical and morphological characterization of collected particles in the suspended particulate matter. Black carbon content was also evaluated by reflectance. Despite the fact that the sampling was not enough to indicate the contribution of each emission source, grouping analysis statistical method allowed to identify two main sources of the particulate matter in suspension: dust soil and sugar cane burning residues

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