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Texto completo: acesso restrito. p. 58–67 Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2014-05-20T13:24:07Z No. of bitstreams: 1 1-s2.0-S0026265X12000975-main.pdf: 1252477 bytes, checksum: 045bc0358d26176c06724bcd75103ca6 (MD5) Made available in DSpace on 2014-05-20T13:24:07Z (GMT). No. of bitstreams: 1 1-s2.0-S0026265X12000975-main.pdf: 1252477 bytes, checksum: 045bc0358d26176c06724bcd75103ca6 (MD5) Previous issue date: 2013 Studies of chemical speciation and phase fractionation of atmospheric inorganic compounds of N, S and Cl have been undertaken in the atmosphere of the Reconcavo Baiano. The objectives were to determine the enrichment of the clean air masses coming from the Atlantic by different chemical species resulting from NO2 SO2, HCl and NH3 emissions from the industrial areas at the Reconcavo and to estimate the changes in air quality regarding between 2008 and 2010. The following sampling devices were used: passive samplers (PS) and continuous analyzers for NO2 and SO2; diffusion tubes coated with citric acid for ammonia and NaF for strong acids (HCl, HNO3 and H2SO4), the latter in a thermodiffusion system with a back-up filter for collection of the thermically stable (140 °C) ammonium salts and other particles < 2 μm. In parallel, Cl−, NO3−, SO42− and NH4+ suspended particles fractionated by size on Nuclepore membrane with a Berner cascade impactor (0.06 to > 14.9 μm). The analytical methodology for the discontinuous measures included ion chromatography (SO2 as SO42− in the PS, anions of the PM and as representants of the acids in the gas phase) and molecular spectrophotometry using the Griess–Saltzman method (λ = 540 nm) and indophenol method (λ = 630 nm) for determination of NO2 and NH3, respectively. Clean air masses from the Atlantic (13 nmol m− 3 HCl, 2.9 nmol m− 3 HNO3, 1.6 nmol m− 3 H2SO4, 9.8 nmol m− 3 SO2, 16 nmol m− 3 NO2 and 84 nmol m− 3 NH3) are slighted enriched in the gas and particulate phase with respect to HNO3 and H2SO4, respectively, by emissions of the industrial complex. However, enrichment occurs for HCl, SO2, NO2 and NH3. In the area of industrial complex influence hydrochloric acid predominates over the other two strong acids, as expected, due to its direct emission from the petrochemical waste incinerator. Ammonium chloride is the predominant gas to particle transformations. During the period of 2008–2010 a decrease varying between 18 and 49% is observed on the levels of almost all compounds in Lamarão do Passé, downwind from an oil refinery but not in Camaçari, downwind from the industrial complex, where all other compounds presented an increased in their concentrations with the exception of HNO3 and HCl.

Texto completo: acesso restrito. p.283-289 Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-07-04T17:28:19Z No. of bitstreams: 1 1-s2.0-S0026265X10000913-main.pdf: 726869 bytes, checksum: bc4a97200cd1fec33a146682c60c4f43 (MD5) Made available in DSpace on 2013-07-04T17:28:19Z (GMT). No. of bitstreams: 1 1-s2.0-S0026265X10000913-main.pdf: 726869 bytes, checksum: bc4a97200cd1fec33a146682c60c4f43 (MD5) Previous issue date: 2010 Reduced sulfur compounds, RSCs (H2S, COS, CH3SH, CH3SCH3, CS2 and CH3S2CH3) play a role in global cycle and acid rain formation. At trace levels RSCs in air are difficult to collect, store and analyze because of their highly adsorptive and reactive properties. This work optimizes parameters of sampling and instrumental determination of RSCs for urban measurements. The method used is based on cryogenic sampling and gas chromatography provided with a cryofocusing trap and flame photometric detection. Greater sampling efficiency was obtained with liquid argon as freezing fluid and air flow rate of 150 mL min− 1 for two hours. Best results have been obtained with preconcentration for 3 min and injection volume of 3 ml. For H2S, CH3SH and CH3S2CH3 the method showed a precision of 89%, limit of detection of 0.10 µg m− 3 and limit of quantification 0.3 µg m− 3. For CH3SCH3 and CS2 the corresponding values were 89%, 0.15 µg m− 3 and 0.5 µg m− 3 and for COS were 75%, 0.18 µg m− 3 and 0.8 µg m− 3 respectively. Sampling efficiency varied between 70–80% for all the RSCs. Accuracy of H2S from field measurements obtained with parallel measurements using a continuous monitor varied between 88 and 98%. The optimized methodology proved to be suitable for field measurements in urban tropical atmospheres with different characteristics.

p. 1180-1189. Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2011-11-23T12:37:51Z No. of bitstreams: 1 a47v31n5.pdf: 214788 bytes, checksum: 71889801afdccde7e1cb1a9e9f46376b (MD5) Made available in DSpace on 2011-11-23T12:37:51Z (GMT). No. of bitstreams: 1 a47v31n5.pdf: 214788 bytes, checksum: 71889801afdccde7e1cb1a9e9f46376b (MD5) Previous issue date: 2008 This work presents a review of sampling and analytical methods that can be applied to atmospheric traces of reduced sulphur compounds (RSC) in the atmosphere. Sampling methodology involving discontinuous methods with preconcentration is mostly used. For the most part, adsorption on solids and cryogenic capture are applied as a procedure. The analysis of these compounds has been done mainly by gas chromatography with FPD, fluorescence and spectrophotometry. Advantages and disadvantages of the methodologies are also mentioned in this paper, aiming to guide the reader towards the most appropriate choice of a sampling and analytical method for RSCs. São Paulo

p. 872-875,July/Aug. Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2011-11-28T12:32:08Z No. of bitstreams: 1 30274.pdf: 990461 bytes, checksum: 1793abda000bb0cb1c98fcdc5fe04713 (MD5) Made available in DSpace on 2011-11-28T12:32:08Z (GMT). No. of bitstreams: 1 30274.pdf: 990461 bytes, checksum: 1793abda000bb0cb1c98fcdc5fe04713 (MD5) Previous issue date: 2006 This study is a result of undergraduate student participation in the Environmental Chemistry discipline provided by the Chemistry Institute/UFBA. The students were involved in the development of passive samplers, a project of the LAQUAM (Environmental Analytical Chemistry Laboratory). The students' residences and other neighborhoods were used to create a passive sampling network, allowing the measurement of atmospheric levels of pollutants in urban areas and in those under industrial influence. The assembly of the passive samplers, including impregnation of filters and chemical analysis were part of the students' practice tasks. The results were analyzed taking into consideration the Brazilian legislation. São Paulo

p. 50-57. Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2012-01-09T17:42:35Z No. of bitstreams: 1 a08v16n1.pdf: 235250 bytes, checksum: 4ef2eed174eb3a9508c6d470c43d881e (MD5) Made available in DSpace on 2012-01-09T17:42:35Z (GMT). No. of bitstreams: 1 a08v16n1.pdf: 235250 bytes, checksum: 4ef2eed174eb3a9508c6d470c43d881e (MD5) Previous issue date: 2005 O desempenho de um amostrador passivo foi testado sob exposição em câmara de Teflon. O SO2 fixado no filtro impregnado com solução de Na2CO3 1,0 x 10-2 mol L-1 foi extraído com uso de banho de ultra-som e solução de H2O2 durante 15 min, e determinado como SO42- por cromatografia iônica. O amostrador apresentou bom desempenho, exceto sob condições de estagnação total do ar (0 m s-1), para períodos de exposição muito curtos (0,5 h), em atmosfera contendo O3 > 150 mg m-3 e compostos reduzidos de enxofre em altas concentrações. A umidade relativa do ar (20 - 80%) e exposição à concentração zero não afetaram o desempenho. Mostrou estabilidade por um mês quando estocado a 4 ºC ou por uma semana à temperatura ambiente (»25 ºC). Sua precisão variou entre 3,5 e 23% dependendo da concentração de SO2 e a exatidão entre 91 e 100%. São Paulo

Trabalho completo: acesso restrito, p. 6425–6429 Submitted by Bruna Lessa (lessbruna@gmail.com) on 2012-09-05T17:05:58Z No. of bitstreams: 1 (197).pdf: 222906 bytes, checksum: 69d820f3b0f9d5990e75d0327a998a5b (MD5) Made available in DSpace on 2012-09-05T17:05:58Z (GMT). No. of bitstreams: 1 (197).pdf: 222906 bytes, checksum: 69d820f3b0f9d5990e75d0327a998a5b (MD5) Previous issue date: 2004-12 Passive samplers have been widely used for over 30 years in the measurement of personal exposure to vapours and gases in the workplace. These samplers have just recently been applied in the monitoring of ambient air, which presents concentrations that are normally much smaller than those found in occupational environments. The locally constructed passive sampler was based on gas molecular diffusion through static air layer. The design used minimizes particle interference and turbulent diffusion. After exposure, the SO2 trapped in impregnated filters with Na2CO3 was extracted by means of an ultrasonic bath, for 15 min, using 1.0×10−2 mol L−1 H2O2. It was determined as SO4−2 by ion chromatography. The performance of the passive sampler was evaluated at different exposure periods, being applied in industrial and urban areas. Method precision as relative standard deviation for three simultaneously applied passive samplers was within 10%. Passive sampling, when compared to active monitoring methods under real conditions, used in urban and industrial areas, showed an overall accuracy of 15%. A statistical comparison with an active method was performed to demonstrate the validity of the passive method. Sampler capacity varied between 98 and 421 μg SO2 m−3 for exposure periods of one month and one week, respectively, which allows its use in highly polluted areas.

The passive sampling technique has been widely used for many years in the measurement of personal exposure to pollutantes in the workplace. In recent years the technique has been used too for measurements in ambient air. In the specific case of SO2 a variety of passive samplers have been described in the literature. The great number are diffusive samplers and some few are permeation samplers. They are basically of two types: badge and tube-type. However there are more than 10 variations in relation to the sampler dimensions, diffusion barriers and pollutant sorption medium. The technique trend to be very used in the near future with samplers able to reach very low detection limits, proposing a viable option for monitoring specific species at urban, regional and global scales.

Submitted by Luciana Silva (lucianassaraujo@ufba.br) on 2021-09-14T14:44:12Z No. of bitstreams: 1 Dissertação esse FINAL 26-05-2017 _1_ _Reparado_.pdf: 11887486 bytes, checksum: c2f58271df632bd2d18764ae80433287 (MD5) Approved for entry into archive by Solange Rocha (soluny@gmail.com) on 2021-09-14T21:05:11Z (GMT) No. of bitstreams: 1 Dissertação esse FINAL 26-05-2017 _1_ _Reparado_.pdf: 11887486 bytes, checksum: c2f58271df632bd2d18764ae80433287 (MD5) Made available in DSpace on 2021-09-14T21:05:11Z (GMT). No. of bitstreams: 1 Dissertação esse FINAL 26-05-2017 _1_ _Reparado_.pdf: 11887486 bytes, checksum: c2f58271df632bd2d18764ae80433287 (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Os efeitos da poluição atmosférica, sobre a saúde afetam a população de forma variável, dependendo principalmente do nível de concentração, do tipo de poluente e do tempo de exposição a esses poluentes. Conhecer sobre a poluição atmosférica é de fundamental importância para que medidas sejam tomadas em relação à prevenção e diminuição de riscos à saúde. Medidas de constituintes do ar podem ser feitas usando equipamentos automáticos, amostragens ativas, eficientes, mas de custo elevado, ou utilizando amostradores passivos, simples, de fácil operação, baixo custo, apresentando concentrações médias para períodos integrados de tempo. Amostradores passivos são dispositivos capazes de fixar gases ou vapores atmosféricos a uma taxa controlada por um processo físico, como difusão, sem envolver bombeamento artificial do ar. Entre as várias formas de nitrogênio presentes na atmosfera estão os óxidos nítrico (NO) e o dióxido (NO2), conhecidos como NOx, estes desempenham um importante papel em reações atmosféricas e podem causar danos a saúde da população e ao meio ambiente. O objetivo deste trabalho foi desenvolver um amostrador passivo (AP) para óxidos de nitrogênio (NOx) na atmosfera, visando medi-los com baixo custo, e amplitude espacial, característica da amostragem passiva. O modelo do amostrador utilizado, construído no LAQUAM (Laboratório de Química Analítica Ambiental, do Departamento de Química Analítica do IQ/UFBA), é baseado em difusão molecular do gás através de uma camada estática de ar, sendo composto de um corpo cilíndrico de polietileno (12 mm de altura e 21 mm de diâmetro interno), com uma membrana de Teflon na entrada, protegida por tela de aço inox. Após o espaço de difusão, encontra-se um filtro de celulose Watman impregnado com uma solução de TEA (Trietanolamina) 10% + solução de PTIO (2-fenil-4,4,5,5-tetrametil imidazolina 3-oxido-1oxyl) 3%. Determinando em paralelo NO2, usando um outro AP, desenvolvido anteriormente no LAQUAM, o qual contém filtro impregnado com solução de TEA 10%, foi possível determinar também concentrações atmosféricas de NO, por subtração dos resultados dos dois APs (NOx e NO2). O NO2 fixado nos amostradores passivos foi extraído com 1,5 mL de água ultrapura em microtubo Eppendorf, seguido de centrifugação por 5 minutos (13.500 rpm) em microcentrifuga, e determinado por espectrofotometria molecular 540 nm pelo método de Griess-Saltzman. O APNOx foi testado quanto à concentração do reagente de impregnação e o tempo de exposição, sendo o período de exposição de 7 dias o que mostrou =-maior eficiência na amostragem passiva de NOx. Foram feitas exposições dos APs em diferentes bairros da cidade de Salvador, possibilitando o conhecimento da faixa de concentração dos óxidos de nitrogênio neste centro urbano (11 - 48 µg m-3 NOx). Estes resultados mostram médias em alguns locais e períodos ultrapassando o limite de 30 µg m-3 NOx, determinado pela União Europeia e Organização Mundial da Saúde. O padrão típico da distribuição dos óxidos de nitrogênio ao longo do dia na atmosfera de Salvador, resultado de medidas ativas contínuas, mostrou ser semelhante nos dois períodos (úmido e seco), resultante da combinação das emissões veiculares e da química atmosférica. The effects of the air pollution on the health affect the population in a variable way, mainly depending on the level of concentration, type of pollutant and time of exposure to these pollutants. To know about the air pollution is of fundamental importance to take measures in relation to the prevention and reduction of health risks. Measurements of air constituents can be done using automatic equipments, efficient active samplings, but of high cost, or using passive samplers, simple, easy operation, low cost, presenting average concentrations for integrated time periods. Passive samplers are devices able to fix atmospheric gases or vapors at a controlled rate by a physical process, such as diffusion, without involving artificial pumping of the air. Among the various forms of nitrogen present in the atmosphere are nitric oxides (NO) and dioxide (NO2), known as NOx, which play an important role in atmospheric reactions and can cause damage to the health of the population and the environment.The objective of this work was to develop a passive sampler (AP) for nitrogen oxides (NOX) in the atmosphere, aiming to measure them at low cost, with spatial amplitude, characteristic of the passive sampling. The used model of the sampler, built in the LAQUAM (Laboratory of environmental Analytical Chemistry of the Analytical Chemistry Department of the IQ/UFBA), is based on molecular diffusion of the gas through a static air layer, composed of a polyethylene cylindrical body (12 mm high and 21 mm internal diameter), with a teflon membrane at the air inlet, protected by a stainless steel screen. After the diffusion path, a cellulose Watman filter impregnated with a solution containing 10% TEA (triethanolamine) + PTIO solution (2-phenyl-4,4,5,5-tetramethyl imidazoline 3-oxido-1-oxyl) 3%. Using in parallel another AP (for NO2), previously developed in the LAQUAM, which contains a filter impregnated with 10% TEA solution, it was possible to determine atmospheric concentrations of NO by subtraction of the results of the two APs (NOx and NO2). The NO2 fixed in the passive samplers was extracted with 1.5 mL of ultrapure water in an Eppendorf microtube, followed by centrifugation for 5 minutes (13,500 rpm) in microcentrifuge, and determined by 540 nm molecular spectrophotometry by the Griess-Saltzman method.The APNox was tested for the concentration of the impregnation reagent and for the exposure time, being 7-days the best exposure period, which showed greater efficiency for the passive NOx sampling. APs exposures were made in different districts of the Salvador city, making possible the knowledge of the concentration range of nitrogen oxides in this urban center (11 - 48 μg m-3 NOx). These results show averages at some sites and periods exceeding 30 μg m-3 NOx, limit determined by the European Union and World Health Organization. The typical pattern of the nitrogen oxides distribution throughout the day in the atmosphere of Salvador, determined with the active continuous measurements showed to be similar in both periods (humid and dry), resulting from the combination of the vehicle emissions and atmospheric chemistry

Submitted by Luciana Silva (lucianassaraujo@ufba.br) on 2021-09-14T14:44:12Z No. of bitstreams: 1 Dissertação esse FINAL 26-05-2017 _1_ _Reparado_.pdf: 11887486 bytes, checksum: c2f58271df632bd2d18764ae80433287 (MD5) Approved for entry into archive by Solange Rocha (soluny@gmail.com) on 2021-09-14T21:05:11Z (GMT) No. of bitstreams: 1 Dissertação esse FINAL 26-05-2017 _1_ _Reparado_.pdf: 11887486 bytes, checksum: c2f58271df632bd2d18764ae80433287 (MD5) Made available in DSpace on 2021-09-14T21:05:11Z (GMT). No. of bitstreams: 1 Dissertação esse FINAL 26-05-2017 _1_ _Reparado_.pdf: 11887486 bytes, checksum: c2f58271df632bd2d18764ae80433287 (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Os efeitos da poluição atmosférica, sobre a saúde afetam a população de forma variável, dependendo principalmente do nível de concentração, do tipo de poluente e do tempo de exposição a esses poluentes. Conhecer sobre a poluição atmosférica é de fundamental importância para que medidas sejam tomadas em relação à prevenção e diminuição de riscos à saúde. Medidas de constituintes do ar podem ser feitas usando equipamentos automáticos, amostragens ativas, eficientes, mas de custo elevado, ou utilizando amostradores passivos, simples, de fácil operação, baixo custo, apresentando concentrações médias para períodos integrados de tempo. Amostradores passivos são dispositivos capazes de fixar gases ou vapores atmosféricos a uma taxa controlada por um processo físico, como difusão, sem envolver bombeamento artificial do ar. Entre as várias formas de nitrogênio presentes na atmosfera estão os óxidos nítrico (NO) e o dióxido (NO2), conhecidos como NOx, estes desempenham um importante papel em reações atmosféricas e podem causar danos a saúde da população e ao meio ambiente. O objetivo deste trabalho foi desenvolver um amostrador passivo (AP) para óxidos de nitrogênio (NOx) na atmosfera, visando medi-los com baixo custo, e amplitude espacial, característica da amostragem passiva. O modelo do amostrador utilizado, construído no LAQUAM (Laboratório de Química Analítica Ambiental, do Departamento de Química Analítica do IQ/UFBA), é baseado em difusão molecular do gás através de uma camada estática de ar, sendo composto de um corpo cilíndrico de polietileno (12 mm de altura e 21 mm de diâmetro interno), com uma membrana de Teflon na entrada, protegida por tela de aço inox. Após o espaço de difusão, encontra-se um filtro de celulose Watman impregnado com uma solução de TEA (Trietanolamina) 10% + solução de PTIO (2-fenil-4,4,5,5-tetrametil imidazolina 3-oxido-1oxyl) 3%. Determinando em paralelo NO2, usando um outro AP, desenvolvido anteriormente no LAQUAM, o qual contém filtro impregnado com solução de TEA 10%, foi possível determinar também concentrações atmosféricas de NO, por subtração dos resultados dos dois APs (NOx e NO2). O NO2 fixado nos amostradores passivos foi extraído com 1,5 mL de água ultrapura em microtubo Eppendorf, seguido de centrifugação por 5 minutos (13.500 rpm) em microcentrifuga, e determinado por espectrofotometria molecular 540 nm pelo método de Griess-Saltzman. O APNOx foi testado quanto à concentração do reagente de impregnação e o tempo de exposição, sendo o período de exposição de 7 dias o que mostrou =-maior eficiência na amostragem passiva de NOx. Foram feitas exposições dos APs em diferentes bairros da cidade de Salvador, possibilitando o conhecimento da faixa de concentração dos óxidos de nitrogênio neste centro urbano (11 - 48 µg m-3 NOx). Estes resultados mostram médias em alguns locais e períodos ultrapassando o limite de 30 µg m-3 NOx, determinado pela União Europeia e Organização Mundial da Saúde. O padrão típico da distribuição dos óxidos de nitrogênio ao longo do dia na atmosfera de Salvador, resultado de medidas ativas contínuas, mostrou ser semelhante nos dois períodos (úmido e seco), resultante da combinação das emissões veiculares e da química atmosférica. The effects of the air pollution on the health affect the population in a variable way, mainly depending on the level of concentration, type of pollutant and time of exposure to these pollutants. To know about the air pollution is of fundamental importance to take measures in relation to the prevention and reduction of health risks. Measurements of air constituents can be done using automatic equipments, efficient active samplings, but of high cost, or using passive samplers, simple, easy operation, low cost, presenting average concentrations for integrated time periods. Passive samplers are devices able to fix atmospheric gases or vapors at a controlled rate by a physical process, such as diffusion, without involving artificial pumping of the air. Among the various forms of nitrogen present in the atmosphere are nitric oxides (NO) and dioxide (NO2), known as NOx, which play an important role in atmospheric reactions and can cause damage to the health of the population and the environment.The objective of this work was to develop a passive sampler (AP) for nitrogen oxides (NOX) in the atmosphere, aiming to measure them at low cost, with spatial amplitude, characteristic of the passive sampling. The used model of the sampler, built in the LAQUAM (Laboratory of environmental Analytical Chemistry of the Analytical Chemistry Department of the IQ/UFBA), is based on molecular diffusion of the gas through a static air layer, composed of a polyethylene cylindrical body (12 mm high and 21 mm internal diameter), with a teflon membrane at the air inlet, protected by a stainless steel screen. After the diffusion path, a cellulose Watman filter impregnated with a solution containing 10% TEA (triethanolamine) + PTIO solution (2-phenyl-4,4,5,5-tetramethyl imidazoline 3-oxido-1-oxyl) 3%. Using in parallel another AP (for NO2), previously developed in the LAQUAM, which contains a filter impregnated with 10% TEA solution, it was possible to determine atmospheric concentrations of NO by subtraction of the results of the two APs (NOx and NO2). The NO2 fixed in the passive samplers was extracted with 1.5 mL of ultrapure water in an Eppendorf microtube, followed by centrifugation for 5 minutes (13,500 rpm) in microcentrifuge, and determined by 540 nm molecular spectrophotometry by the Griess-Saltzman method.The APNox was tested for the concentration of the impregnation reagent and for the exposure time, being 7-days the best exposure period, which showed greater efficiency for the passive NOx sampling. APs exposures were made in different districts of the Salvador city, making possible the knowledge of the concentration range of nitrogen oxides in this urban center (11 - 48 μg m-3 NOx). These results show averages at some sites and periods exceeding 30 μg m-3 NOx, limit determined by the European Union and World Health Organization. The typical pattern of the nitrogen oxides distribution throughout the day in the atmosphere of Salvador, determined with the active continuous measurements showed to be similar in both periods (humid and dry), resulting from the combination of the vehicle emissions and atmospheric chemistry

Submitted by NUBIA OLIVEIRA (nubia.marilia@ufba.br) on 2018-10-19T17:10:02Z No. of bitstreams: 1 Dissertação corrigida.pdf: 1684958 bytes, checksum: af08e3969b3bf98ca96e309a0a6d0b1b (MD5) Approved for entry into archive by NUBIA OLIVEIRA (nubia.marilia@ufba.br) on 2018-10-19T18:10:46Z (GMT) No. of bitstreams: 1 Dissertação corrigida.pdf: 1684958 bytes, checksum: af08e3969b3bf98ca96e309a0a6d0b1b (MD5) Made available in DSpace on 2018-10-19T18:10:46Z (GMT). No. of bitstreams: 1 Dissertação corrigida.pdf: 1684958 bytes, checksum: af08e3969b3bf98ca96e309a0a6d0b1b (MD5) O presente trabalho propõe estratégias analíticas para determinação de constituintes inorgânicos em medicamentos e suplementos minerais à base de magnésio empregando espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). Inicialmente foi avaliado o efeito de matriz causado pela alta concentração de Mg nos espectros dos elementos As, Ba, Cd, Co, Fe, K, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sn, Sr, V e Zn e nas curvas analíticas de calibração. As linhas selecionadas para cada elemento de acordo com o estudo dos espectros foram, em nm: As (I) 193,696, Ba (I) 455,403, Cd (II) 226,502, Co (II) 238,892, Fe (II) 238,204, K (I) 766,491, Mn (II) 257,610, Mo (I) 202,032, Na (II) 589,592, Ni (II) 216,55, P (I) 213,618, Pb (II) 220,353, Sb (I) 206,834, Se (II) 203,985, Sn (II) 189,927, Sr (II) 407,771, V (II) 311,837 e Zn (I) 213,857. Foram realizados estudos para correção dos efeitos de matriz empregando os seguintes padrões interno (PI): Y (II) 360,074, Sc (II) 361,383 e Be (II) 313,042. A utilização do Be (II) 313,042 como PI mostrou resultados satisfatórios para correção do efeito de matriz para Ba, Cd, Co, Mn, Ni e Pb. Dois métodos foram propostos empregando decomposição em bloco digestor e em forno de micro-ondas com cavidade cujas condições foram selecionadas com base no carbono residual e na acidez residual. A validação foi realizada avaliando-se os limites de detecção (LOD) e de quantificação (LOQ), análise do material certificado FO-01/2012 USP Brachiaria Brizantha cv Marandu enriquecido com Mg, ensaios de adição e recuperação de analitos e precisão. O procedimento empregando forno de micro-ondas com cavidade foi mais eficiente de acordo com os resultados da validação e dos teores de carbono residual quando comparado com a decomposição utilizando bloco digestor. O método proposto foi aplicado nas amostras de suplemento minerais à base de magnésio e leite de magnésia. As faixas de concentração para os elementos determinados em mg g-1 foram: As (0,080-0,099), Ba (0,089-0,097), Ni (0,040-0,046), Pb (0,036-0,042), Cd (0,029-0,033) e Co (0,039-0,045), Sn (0,095-0,246), Se (0,093-0,107), Fe (0,111-4,52), Na (0,132-0,462), K (0,136-2,13), Mn (0,034-0,614), P (0,202-0,928) e Zn (0,092-0,194). Os teores bioacessíveis em % para esses elementos foram Na (79-92), Fe (48-53), K (32-48), P (48-51) e Zn (39-41). De acordo com os resultados encontrados Na foi o elemento que se mostrou mais bioacessível para essas matrizes. As amostras de suplemento minerais à base de magnésio apresentaram teores bioacessíveis para o Mg na faixa de 68-70%. A contribuição deste trabalho está relacionada às estratégias que viabilizaram a avaliação da composição em termos de constituintes inorgânicos em medicamento e suplementos com alto teor de magnésio. This paper proposes analytical strategies for the determination of inorganic constituents in medicines and minerals magnesium supplements using optical emission spectrometry with inductively coupled plasma (ICP OES). Initially it evaluated the matrix effect caused by high concentration of Mg in the spectra of the elements As, Ba, Cd, Co, Fe, K, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sn, Sr, V and Zn and the analytical calibration curves. The lines selected for each element according to the study of the spectra were: As (I) 193.696, Ba (I) 455.403, Cd (II) 226.502, Co (II) 238.892, Fe (II) 238.204, K (I) 766.491, Mn (II) 257.610, Mo (I) 202.032, Na (II) 589.592, Ni (II) 216.55, P (I) 213.618, Pb (II) 220.353, Sb (I) 206.834, Se (II) 203.985, Sn (II) 189.927, Sr (II) 407.771, V (II) 311.837 e Zn (I) 213.857. Studies were performed to correct for matrix effects using the following internal standards (IS): Y (II) 360.074, Sc (II) 361.383 and Be (II) 313.042. The use of Be (II) 313.042 as IS showed satisfactory results for correction of matrix effect for Ba, Cd, Co, Mn, Ni and Pb. Two methods have been proposed employing decomposition block digestor and microwave oven cavity whose conditions were selected based on the residual carbon and residual acidity. The validation was performed evaluating the limits of detection (LOD) and quantification (LOQ), analysis of certified material FO-01/2012 USP Brachiaria Brizantha cv Marandu enriched with Mg, addition and recovery test analytes and accuracy. The procedure employing microwave oven with cavity was more efficient in accordance with the results of the validation and the residual carbon content as compared with the decomposition using digester block. The proposed method was applied to mineral magnesium supplement samples and milk of magnesia. The concentration ranges for the elements determined in mg g-1 were: As (0.080-0.099), Ba (0.089-0.097), Ni (0.040-0.046), Pb (0.036-0.042), Cd (0.029-0.033) e Co ( 0.039-0.045), Sn (0.095-0.246), Se (0.093-0.107), Fe (0.1114.52), Na (0.132-0.462), K (0.136-2.13), Mn (0.034-0.614), P (0.202-0.928) and Zn (0.092-0.194). The bioaccessibility content in % for those elements were Na (79-92), Fe (48-53), K (32-48), P (48-51) e Zn (39-41). According to the results, the Na was the element that was more bioaccessible for these matrices. The mineral magnesium supplement samples were bioaccessibility for Mg levels in the range of 68-70%. The contribution of this work is related to the strategies that enabled the evaluation of the composition in terms of inorganic constituents in medicine and supplements with high magnesium content.

Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-04-11T12:25:57Z No. of bitstreams: 1 Dissertaçao_Daniela Franca.pdf: 3281621 bytes, checksum: 1287b71780131176ad9b8eb7d8ab7741 (MD5) Approved for entry into archive by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-05-10T13:34:42Z (GMT) No. of bitstreams: 1 Dissertaçao_Daniela Franca.pdf: 3281621 bytes, checksum: 1287b71780131176ad9b8eb7d8ab7741 (MD5) Made available in DSpace on 2016-05-10T13:34:42Z (GMT). No. of bitstreams: 1 Dissertaçao_Daniela Franca.pdf: 3281621 bytes, checksum: 1287b71780131176ad9b8eb7d8ab7741 (MD5) As crescentes taxas de urbanização, a deficiência de políticas públicas de transporte coletivo, além dos incentivos à produção e compra de veículos no país têm implicado em um aumento expressivo da motorização individual elevando a demanda pelo consumo de combustíveis, levando, por consequência, ao aumento gradativo na taxa de emissão de poluentes atmosféricos. Benzeno, tolueno, etilbenzeno, e os xilenos (o+m+p) - mais conhecidos pela sigla BTEX são poluentes predominantemente emitidos pela frota veicular e apresentam impacto nocivo à saúde humana, pois são bastante tóxicos e, no caso do benzeno, apresenta potencial carcinogênico. Adicionalmente, estes monoaromáticos são considerados importantes precursores na formação do ozônio troposférico. Apesar disso, poucos estudos sobre os níveis de BTEX em atmosferas urbanas têm sido realizados no Brasil. Este trabalho teve como objetivo realizar um estudo sobre os níveis de BTEX em áreas urbanas na cidade de Salvador-BA, utilizando amostragem passiva, visando o diagnóstico da qualidade do ar com baixo custo. Foram utilizados amostradores passivos difusivos da marca Radiello® contendo carvão ativado como adsorvente, que foram expostos durante 14 dias em períodos chuvoso e seco. Os compostos BTEX adsorvidos foram extraídos com 1,0 mL de dissulfeto de carbono (CS2), em banho de ultrassom com água gelada a 15 °C durante 10 min com agitação manual a cada 2 min, sendo posteriormente determinados por cromatografia a gás com detecção por ionização em chama. O método cromatográfico foi validado através da avaliação dos seguintes parâmetros: seletividade, linearidade, precisão, exatidão, limites de detecção e de quantificação e robustez. As concentrações de BTEX apresentaram pouca variação em função do efeito sazonal e encontraram-se na faixa de 0,46-3,47 μg m-3 para benzeno, 0,49- 4,51 μg m-3 para tolueno, 0,42-1,72 μg m-3 para etilbenzeno, 0,25-1,79 μg m-3 para m,p-xileno e 0,39-1,07 μg m-3 para o-xileno. Algumas razões de diagnóstico e análises de correlações entre os BTEX foram utilizadas para a identificação da origem das emissões e com base nos resultados, foi possível inferir que as regiões de estudo são influenciadas principalmente pelas emissões veiculares. Através da avaliação do potencial de formação de ozônio, verificou-se que m,p-xileno e tolueno são responsáveis por aproximadamente 75% de todo o ozônio produzido, a partir de reações envolvendo os compostos BTEX, no período chuvoso. Para a avaliação das relações entre as concentrações de BTEX, parâmetros meteorológicos e concentrações de poluentes convencionais foram realizadas análises de componentes principais e de agrupamento hierárquico, além da matriz de correlação linear, as quais demonstraram que, de maneira geral, nos locais de monitoramento existem correlações e similaridades significativas entre as concentrações dos poluentes, indicando que eles são provenientes da mesma fonte de emissão, além de algumas correlações importantes entre BTEX e parâmetros meteorológicos. The increasing urbanization rates, the public policy deficiency of public transportation, in addition to the incentives for production and purchase of vehicles in the country have been resulting in a significant growth in the individual usage of vehicles, increasing the demand for fuel consumption, consequently leading to a gradual increase in the emission rate of air pollutants. Benzene, toluene, ethylbenzene, and xylenes (o + m + p) - better known by the acronym BTEX are pollutants predominantly released by the vehicle fleet and have harmful impact on human health, as they are quite toxic and in, the case of benzene, has carcinogenic potential. Additionally, these monoaromatics are considered important precursors in the formation of tropospheric ozone. Nevertheless, few studies on the BTEX levels in urban atmospheres have been made in Brazil. This work aimed to conduct a study on the BTEX levels in urban areas in the city of Salvador, Bahia, using passive sampling, for the diagnosis of air quality at low cost. Diffusive Passive samplers of Radiello® brand containing activated carbon as adsorbent, which were exposed for 14 days in rainy and dry seasons were used. The adsorbed BTEX compounds were extracted with 1.0 mL of carbon disulfide (CS2) in ultrasonic bath with ice water at 15 ° C for 10 min with manual stirring every 2 min, subsequently determined by gas chromatography with flame ionization detection (FID). The chromatographic method was validated by evaluating the following parameters: selectivity, linearity, precision, accuracy, detection and quantification limits and robustness. The BTEX concentrations show little variation due to seasonal effects and were showed in the range of 0.46 to 3.47 μg m-3 for benzene, 0.49 to 4.51 μg m-3 for toluene, 0.42 -1.72 μg m-3 to ethylbenzene, 0.25 to 1.79 μg m-3 to m, p-xylene and from 0.39 to 1.07 μg m-3 for o-xylene. Some reasons for diagnosis and analysis of correlations between BTEX were used to identify the source of emissions and based on the results, it was possible to infer that the regions of study are mainly influenced by vehicle emissions. By evaluating the ozone forming potential, it was found that m, p-xylene and toluene are responsible for approximately 75% of all the ozone produced from reactions involving BTEX compounds in the rainy season. For the evaluation of the relationship between the concentrations of BTEX, meteorological parameters and concentrations of conventional pollutants, principal component analysis and hierarchical clustering were carried out, beyond the linear correlation matrix, which showed that, in general, there exist correlations and significant similarities between the concentrations of pollutants at the monitoring sites, indicating that they come from the same emission source, as well as some important correlations between BTEX and meteorological paramete

Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2014-09-17T17:51:04Z No. of bitstreams: 1 (Dissertação_mestrado__(03.11_)).pdf: 1756144 bytes, checksum: 6a5c8a2f486f154eba91b5aa9780dde0 (MD5) Approved for entry into archive by Fatima Cleômenis Botelho Maria (botelho@ufba.br) on 2014-09-19T12:24:04Z (GMT) No. of bitstreams: 1 (Dissertação_mestrado__(03.11_)).pdf: 1756144 bytes, checksum: 6a5c8a2f486f154eba91b5aa9780dde0 (MD5) Made available in DSpace on 2014-09-19T12:24:04Z (GMT). No. of bitstreams: 1 (Dissertação_mestrado__(03.11_)).pdf: 1756144 bytes, checksum: 6a5c8a2f486f154eba91b5aa9780dde0 (MD5) CNPQ A determinação de metais em águas naturais por Espectrometria de Emissão Óptica com Plasma Indutivamente Acoplado (ICP OES), em geral, deve envolver etapas de pré- concentração, devido os níveis de concentração dos metais em água serem muitas vezes abaixo dos limites de detecção da técnica. Dessa forma, o objetivo desse trabalho foi desenvolver um método de pré-concentração em fase sólida sensível e simples para a determinação de cobre, ferro, níquel, manganês, chumbo e zinco em amostras de água por ICP OES. As condições experimentais para pré-concentração foram otimizadas considerando os fatores: concentração do eluente, volume de eluente, volume da amostra, vazão e pH. As condições otimizadas corresponderam ao uso de 5 mL de solução de HCl 0,8 mol L-1 como eluente, volume da amostra de 50 mL, vazão de 1,9 mL min-1 e pH 9,0. Para a determinação dos metais, as amostras, após ajuste do pH, foram percoladas com o auxílio de uma bomba peristáltica em cartucho Sep-pak C18 com 1-(2-piridilazo)-2-naftol (PAN) imobilizado na sílica funcionalizada C18. A eluição dos analitos foi realizada com a passagem da solução de HCl pelo cartucho para posterior determinação por ICP OES. Nestas condições, os limites de detecção para Cu, Fe, Mn, Ni, Pb e Zn obtidos variaram entre 0,11 e 21 µg L-1 e os limites de quantificação entre 0,36-69 µg L-1, respectivamente. Os desvios padrão relativos (R.S.D.) para a determinação dos analitos não ultrapassaram 9 %. O efeito de possíveis espécies interferentes sobre a recuperação dos analitos também foram investigados. A exatidão do método foi avaliada mediante análise de material de referência certificado (SLEW-3 Estuariene Water Reference Material for Trace Metals) e o método proposto foi aplicado para análise de amostras de água subterrânea, água potável e água de rio coletadas nos municípios de Cachoeira e São Félix, Bahia, Brasil. As amostras foram analisadas por Espectrometria de Massas com Plasma Indutivamente Acoplado (ICP-MS) como método comparativo, não sendo observadas diferenças significativas entre estes resultados e os resultados obtidos pelo método proposto. The determination of metals in natural waters by Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES), in general, involves pre-concentration steps, due the concentration levels of metals in water are often below the limits of detection of this technique. In this way, the objective of this work was to develop a pre-concentration solid phase method for sensitive and simple determination of copper, iron, nickel, manganese, lead and zinc in water samples by ICP OES. The experimental conditions for pre- concentration were optimized considering the following factors: the concentration of the eluent, eluent volume, sample volume, flow-rate and pH. The optimized conditions corresponded to the use of 5 mL of HCl solution 0.8 mol L-1 as an eluent sample volume 50 ml, flow-rate 1.9 mL min-1 and pH 9.0. For the determination of metals by the procedure, the samples after pH adjustment were percolated with the aid of a peristaltic pump on Sep-Pak C18 cartridge with 1-(2-pyridylazo)-2-naphthol (PAN). The analyte elution was carried out with the passage of the HCl solution in the cartridge for subsequent determination by ICP OES. In these conditions, the detection limit for Cu, Fe, Mn, Ni, Pb and Zn varied between 0.11 to 21 μg L-1 and the limits of quantification from 0.36 to 69 μg L-1, respectively. The relative standard deviation (RSD) for the analytes of this study did not exceed 9%. The effect of possible interfering species on the recovery of the analytes was also investigated. The accuracy of the method was evaluated by analysis of certified reference material (SLEW-3 Estuariene Water Reference Material for Trace Metals) and the proposed method was applied to samples of ground water, drinking water and river water collected in Cachoeira and São Félix cities, Bahia, Brazil. The samples were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) as a comparative method do not being found significant differences among these results and the results obtained by the proposed method.