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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.
21

Avaliação do risco de infecção cruzada através das linhas d água dos equipos odontológicos na rede pública estadual de Alagoas / Assessment of risk of cross infection through the waterlines in public dental units in Alagoas

Lisboa, Guacyra Machado 03 June 2011 (has links)
During routine work, the dental staff and patients are exposed to contamination by water used in dental units, through accidental ingestion or aspiration of aerosols generated by high-speed and air-water syringe. This study evaluated the water quality of the dental equipment of public dental offices in Alagoas, conducting the count of heterotrophic bacteria, filamentous fungi, as well as the presence of total and fecal coliforms and Streptococcus mutans. We collected water from air-water syringe, supply hoses with handpieces disconnected, handpieces with supply hose attached, reservoir and water where the reservoir was filled from six dental offices. To search for heterotrophic bacteria and fungi volumes of 100 μL of pure sample and 10-1 dilution were plated in duplicate on plate count agar medium supplemented with 50 mg.L-1 of Ketoconazole and Sabouraud dextrose agar supplemented with chloramphenicol and amplicilina, 50 mg.L-1 of each. The results were expressed in CFU/mL. For quantification of total and fecal coliforms, we used the method of enzyme substrate (Colilert ®) and the results were expressed in MPN/100ml, according to a table supplied by the manufacturer. The research of S. mutans was accomplished through the use Mitis Salivarius Bacitracin with and without prior disinfection with alcohol 70% of the collection points in Petri dishes and a vial with medium Mitis Salivarius Bacitracin Sucrose without prior disinfection of the collection points. All results were expressed in CFU/mL and subjected to molecular analysis to confirm the identities. We did not observe the isolation of Streptococcus mutans. However the high contamination found indicated that the water was unfit for human consumption can be considered a potential source of cross infections. / Durante a rotina de trabalho, a equipe odontológica e os pacientes estão expostos a contaminação pelas águas utilizadas nas unidades dentais, através da ingestão acidental ou aspiração dos aerossóis gerados pela caneta de alta rotação e seringa tríplice. O presente estudo avaliou a qualidade da água dos equipamentos odontológicos da rede pública estadual de Alagoas, realizando a contagem de bactérias heterotróficas, a presença de coliformes totais e termotolerantes, assim como contagem de fungos filamentosos, potencialmente patogênicos e a presença de Streptococcus mutans. Foram coletadas água, da seringa tríplice, caneta de alta rotação com a peça de mão acoplada e desacoplada às mangueiras, reservatório de água e do local onde era abastecido o reservatório; de seis consultórios odontológicos. Para pesquisa de bactérias heterotróficas e fungos filamentosos volumes de 100 μl da amostra original e da diluição 10-1 foram semeados em duplicata, em meio Plate Count Agar adicionado de 50 mg.L-1 de Cetoconazol e em Agar Sabouraud dextrose adicionado de cloranfenicol e amplicilina, 50 mg.L-1 de cada. Os resultados foram expressos em UFC/mL. Para quantificação de coliformes totais e termotolerantes, foi utilizado o método do substrato enzimático (Colilert®) e os resultados foram expressos em NMP/100 mL, de acordo com tabela fornecida pelo fabricante. A pesquisa de S. mutans foi realizada utilizado o meio Mitis Salivarius Bacitracina com e sem desinfecção prévia com álcool a 70% dos pontos de coleta em placas de Petri e em um laminocultivo com meio Mitis Salivarius Bacitracina Sacarose sem limpeza prévia dos pontos de coleta. Todos os resultados foram expressos em UFC/mL e submetidos a testes moleculares para confirmação das identidades. Não foi observado o isolamento de Streptococcus mutans. Porem a alta contaminação encontrada indicou que a água era imprópria para o consumo humano; podendo ser considerada uma fonte potencial de infecções cruzadas.
22

Contaminação de agrotóxicos na água para consumo humano no RS : avaliação de riscos, desenvolvimento e validação de método empregando SPE e LC-MS/MS

Zini, Luciano Barros January 2016 (has links)
Os agrotóxicos, quando presentes na água, são definidos como micropoluentes: mesmo em baixas concentrações, conferem à água características de toxicidade. Aponta-se o RS como o quarto estado do Brasil com maior volume de vendas anuais de agrotóxicos, chegando a mais de 50 mil toneladas por ano. Desde 2014 está em vigência no território gaúcho uma portaria estadual que acrescenta a exigência de 46 parâmetros de agrotóxicos no padrão de potabilidade da água, além dos 27 já exigidos pela portaria nacional. Neste trabalho, 89 pesticidas foram avaliados conforme três métodos teóricos de predição de risco de contaminação em mananciais subterrâneos e superficiais: índice Ground Ubiquity Score (GUS), método Screening da USEPA e método de GOSS, baseados nas propriedades físico-químicas dos pesticidas. Nos anos de 2015 e 2016, foram realizadas 143 coletas de água para consumo humano em 45 municípios da bacia hidrográfica do Alto Jacuí (G-50), a que possui a maior taxa de aplicação de agrotóxicos do estado, para análises de vigilância através de laboratório contratado, envolvendo os 89 pesticidas presentes na portaria nacional e estadual. Em paralelo, 183 pesticidas presentes em uma solução-padrão foram empregados no desenvolvimento de um novo método de análise multiresíduos, com etapas de pré-tratamento por filtração seguidas por extração em fase sólida e LC-MS/MS, aplicada para os três maiores municípios da G-50 (Carazinho, Soledade e Cruz Alta) em amostras de água bruta e tratada, durante quatro períodos de aplicação de agrotóxicos dos principais cultivos agrícolas da região. Dos pesticidas mencionados nas portarias nacional e estadual, 12 foram classificados com o maior risco de contaminação tanto em água superficial e subterrânea de acordo com os três métodos teóricos empregadas. Nas análises de vigilância foi detectado permetrina em Carazinho e alaclor em Espumoso. No método desenvolvido, 75 pesticidas foram validados de acordo com os critérios propostos e atingiram limites de detecção (LD) e limites de quantificação (LQ) que variaram de 10 a 300 ng L-1. Na aplicação do método nas coletas dos três municípios da G-50 não houve detecção de nenhum pesticida. / Agrochemicals, when present in water, are defined as micropollutants, thus giving the water toxic characteristics, even at low concentrations. The Rio Grande do Sul state in Brazil was found to rank fourth in annual agrochemical sales in the country, surpassing 50 thousand tons per year. A state regulation in effect in the RS state since 2014 requires the inclusion of 46 new agrochemical parameters concerning the standards for potable drinking water, in addition to 27 existing parameters mandated by national ordinance. Seventy-five pesticides were evaluated based on three theoretical methodologies of contamination risk prediction in underground and surface water sources, by measuring the physicochemical properties of pesticides: GUS index, USEPA screening method and Goss method. In 2015 and 2016, 143 water samples were collected from sources of potable water in 45 municipalities located in the Alto Jacuí river basin, a region which has the highest pesticide application rate in the RS state. A private laboratory analyzed samples from 89 pesticides present in the national and state regulation. Paralely, 183 pesticides were evaluated by a new multi-residue analysis method. Filtration was conducted in the pre-treatment steps, followed by a solid phase extraction liquid chromatography coupled with mass spectrometry analysis (SPE-LC-MS/MS) of raw and treated water samples from the three largest G-50 municipalities (Carazinho, Soledade and Cruz Alta), during the four pesticide application periods of the main crops cultivated in the region. Twelve pesticides were classified as of high risk in terms of contamination for both surface and groundwater, in accordance with the three theoretical methodologies implemented. During analysis of the surveillance data collected, the pesticides permethrin and alachlor were found in Carazinho and Espumoso, respectively. Through the methodology developed, 75 pesticides were evaluated according to the criteria proposed, reaching lower detection limit (LD) and quantification limit (LQ) ranging from 10 to 300 ng L-1, respectively. During the implementation of the methodology for sample collections in the three G-50 municipalities, no pesticides were detected.
23

Synthesis of smart nanomaterials for preconcentration and detection of E.coli in water

Mahlangu, Thembisile Patience 06 1900 (has links)
It is common knowledge that water is one of the basic needs for human beings. However, the consumption of contaminated water can lead to waterborne diseases and fatalities. It is, therefore imperative to constantly monitor the quality of potable water. There are numerous technologies used for water quality monitoring. These technologies are relatively effective however these tests are expensive and complex to use, which then require experienced technicians to operate them. Other tests are not rapid, making consumers of water susceptible to waterborne diseases. In this study, dye-doped, surface functionalized silica nanoparticles (SiNPs) and surface-functionalized magnetic nanocomposites (MNCs) were proposed as materials that can be applied in order to reduce the time taken to get results as well as to make the processes less complex and portable. The aim of this study was to synthesize and characterize surface functionalized dye-doped SiNPs and surface functionalized MNCs for detection and preconcentration of in water. Additionally, proof of concept had to be shown using the synthesized materials. SiNPs were the materials of choice due to their easily functionalized surfaces and their strong optical properties. SiNPs are photostable and they do not leach in solution due to the inert nature of the silica matrix in aqueous media. MNCs were chosen as materials of choice for preconcentration of E. coli in water because they are easy to synthesize and they can be applied in various biological applications due to their functional groups. SiNPs were synthesized using the water-in-oil microemulsion. The SiNPs were further functionalized with amine and carboxyl groups and avidin. Thereafter, they were bioconjugated with biotinylated anti-E. coli antibodies. The pure and surface functionalized SiNPs were characterized using ATR-FTIR spectroscopy, FE-SEM, HR-TEM, Zeta Sizer, UV-vis spectroscopy and spectrofluorometry. The application of the dye—doped surface functionalized SiNPs in E. coli detection was characterized using the fluorescence plate reader. The SiNPs were spherical and uniform in size. They increased in size as they were being functionalized, ranging from 21.20 nm to 75.06 nm. The SiNPs were successfully functionalized with amine and carboxyl groups as well as with avidin and antibodies. Two methods were investigated for carboxyl group attachment (direct and indirect attachment) and the direct attachment method yielded the best results with a surface charge of -31.9 mV compared to -23.3 mV of the indirect method. The dye loading was found to be 1% after particle synthesis. The optical properties of the Ru(Bpy) dye were enhanced 3 fold when they were encapsulated in the Si matrix. The SiNPs were binding to the E. coli cells and enabled detection. MNCs were synthesized through in-situ polymerization. The MNCs were characterized using ATR-FTIR spectroscopy, SEM, TEM and XRD. The MNCs were successfully functionalized with carboxyl groups. The increase in size of the nanocomposites as seen in SEM images proved that the Fe3O4 was successfully encapsulated in the polymer matrix. The MNCs were proven to be magnetic by a simple magnetism test whereby they were separated in an aqueous solution using an external magnetic field. The antibody-labelled MNCs were binding to the E. coli cells as shown in TEM images. E. coli cells were removed from water at varying concentrations of 1x106 CFU/mL to 1x109 CFU/mL at 10 mL volumes. This study has demonstrated that dye-doped SiNPs amplify the signal of E. coli cells using fluorescence. The study has also demonstrated that the MNCs can be applied in sample preconcentration and enrichment for E. coli detection. However, further studies should investigate and optimize the combination of the two techniques in a point of use device for water quality testing of 100 mL-samples as per the requirement of the SANS 241 standard. / Civil and Chemical Engineering / M. Tech. (Chemical Engineering)
24

Qualidade da água ao longo do Rio Capivara no município de Botucatu - SP

Silva, Kelly Cristina da [UNESP] 19 June 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-06-19Bitstream added on 2014-06-13T20:15:40Z : No. of bitstreams: 1 silva_kc_me_botfca.pdf: 731160 bytes, checksum: c86e329e8529f69627dec6c28bbecbb7 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / O objetivo do presente trabalho foi caracterizar a qualidade de água ao longo do Rio Capivara analisando parâmetros que definam seus aspectos quantitativos e qualitativos em diferentes pontos, desde a nascente até a foz para poder contribuir com a preservação e proteção do manancial. A escolha da área estudada levou em consideração a possibilidade futura do uso da água do Rio Capivara para abastecimento urbano, já que a população cresce a cada dia. Para isso houve a necessidade de um levantamento das características ao longo do rio, considerando pontos pré-estabelecidos por visitas aos locais e pela facilidade de acesso. Para verificar as variações dos parâmetros analisados durante as diferentes estações do ano, as coletas foram realizadas nos meses de novembro e dezembro de 2005 referentes à estação da primavera, janeiro e fevereiro de 2006 referente ao verão, abril e maio de 2006 referente ao outono, finalizando com julho e agosto de 2006 referente ao inverno. Analisando os resultados obtidos, pode-se concluir que as águas do Rio Capivara mostraram-se satisfatórias durante grande parte do ano. Portanto, o Rio Capivara pode ser enquadrado na Classe I, de acordo com Conama, Resolução nº 357, de 17 de Março de 2005. No entanto vale lembrar que pelo fato de ser um manancial de grande importância e torna-se necessário a adoção de práticas conservacionistas mais adequadas na área do Rio Capivara e também promover a recomposição da mata ciliar em toda a sua extensão, buscando melhorar seu estado ecológico. / This study intended to characterize the water quality across the Capivara River to analyzed parameters that define its quantitative and qualitative aspects in different points, since the nascent until the estuary to be able to contribute with their preservation and protection. The choice of the studied area considered the future possibility of the Capivara River water used for urban supplying, since the population grows to each day. To this there was necessity of a survey of its characteristics across the river, considering 5 points already established for visits to the places and access easiness. The collections had been carried in the months November and December of 2005 referring ones to the spring station, January and February of 2006 referring to summer, April and May of 2006 referring to autumn, finishing July and August referring to winter; to verify the variations of analyzed parameters during the different stations of the year. Analyzing the gotten results, it can be concluded that the Capivara River waters had shown satisfactory during great part of the year. Therefore the Capivara River can be in accordance with the Conama Class I, Resolution nº 357, of March of 17th of 2005. However itþs important remember that is a great importance source and becomes necessary the adoption of soil conservation practicals adjusted in the area of Capivara River and also to promote the vegetation bush implantation in all its extension searching, to improve its ecological state.
25

Avaliação da contaminação de águas subterrâneas por cemitérios: estudo de caso de Tabuleiro - MG / Evaluation of contamination of groundwater by graveyards: a case study Tabuleiro - MG

Fineza, Adonai Gomes 11 July 2008 (has links)
Made available in DSpace on 2015-03-26T13:28:01Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2582380 bytes, checksum: b9fbd236488a351a41b326a133eff320 (MD5) Previous issue date: 2008-07-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents the results of a case study carried out at Tabuleiro graveyard, located at Minas Gerais State, southeast Brazil. The graveyard is located at Formoso river flood plain. Several chemical and physical analyses were done at underground water collected at monitoring wells installed inside the graveyard and on its surrounds. Monitoring wells were positioned so possible aquifer contamination from the graveyard could be detected. The following parameters were analyzed: nitrate, ammoniated nitrogen, BOD, QOD, pH, electrical conductivity, temperature, total phosphorus, calcium, magnesium, sodium, total coliforms and E. coli. Water sampling was made monthly from august, 2007 to march, 2008, resulting in seven different samples from each well. High electrical conductivity values – typically found in saline or residual water were found at well number 5, located below the cemetery on underground flow direction. These values are associated with high values for ammoniated nitrogen, calcium, magnesium, sodium and E. coli. As a conclusion, graveyards can behavior as a source of pollution/contamination of underground water by flowing of burial leakage. / O presente trabalho apresenta os resultados de um estudo de caso realizado no cemitério da cidade de Tabuleiro (MG), localizado na planície de inundação do Rio Formoso e em seu entorno. Nestas análises foram analisadas amostras de água subterrânea coletadas em poços de monitoramento instalados dentro da área do cemitério e em seu entorno, pelas quais foi acompanhado o grau de contaminação do aqüífero. Foram avaliados os parâmetros: nitrato, nitrogênio amoniacal, DBO, DQO, pH, condutividade hidráulica, condutividade elétrica, temperatura, fósforo, cálcio, sódio, potássio, magnésio, coliformes totais e Escherichia Coli, em sete campanhas mensais realizadas no período de agosto de 2007 a março de 2008. Foi encontrado valores elevados de condutividade elétrica (típicos de águas salinas ou águas residuárias) no poço de monitoramento 5 a jusante do cemitério, valores estes associados à presença elevada de amônia, cálcio, magnésio e sódio. A estes parâmetros soma-se a presença elevada de Escherichia coli. Concluindo-se, portanto, que cemitérios podem constituir fonte de poluição/contaminação de águas subterrâneas, por escoamento de necrochorume.
26

Adsorption of perfluorinated water contaminants on Agave sisalana activated carbon fibre

Imwer, Serge Mapan January 2014 (has links)
Thesis submitted in fulfilment of the requirements for the degree Magister Technologiae: Chemical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2014 / An awareness campaign on the harmful effects of Perfluorinated compounds (PFCs), especially Perfluorooctanoic acid (PFOA) and Perfluorooctane sulfonate (PFOS) has been conducted to inform the general public about the impact of these organic compounds on hu-mans and biota. These compounds have been shown to be potential carcinogens, as indi-cated by the United States Environmental Protection Agency (USEPA) and the Organization for Economic Co-operation and Development . A major concern about these chemicals is that they have been widely used in consumer products and have been detected in food and drinking water. They have been determined to be resistant to biological degradation, owing to their unique chemical and physical properties (fluorine atoms that have substituted hydrogen atoms in their chemical structure). Owing to their characteristics of being highly soluble in water, they cannot be removed from water using ordinary purification processes. Studies have been conducted to evaluate the removal of PFOA and PFOS from water using different methods. Among these methods, it has been proved that adsorption is a suitable method with the best adsorbent identified as activated carbon (AC). AC can be found in many forms, including as a fibre. The use of AC for the removal of PCFs can be augmented with sonica-tion and electro-chemical methods for rapid absorption of these compounds. The aim of this study was to remove these contaminants using a microporous AC fibre (ACF) made from an indigenous plant, Agave sisalana, which is widely available across sub-Saharan Africa, by using electro-physico-chemical methods. ACF has the following advantages when compared with granulated and/or powdered AC: it has a slightly larger reactive surface area; small quantities can be used; it is easily handled; it retains its shape under stress, thus does not require additional filtration to remove particulate residue; and can be regenerated easily. The manufacturing process of the ACF was done in several steps: 1) harvesting of the A. sisalana leaves, stripping them to obtain wet fibre by scrapping using traditional meth-ods, 2) chemical activation using NaOH, KOH, ZnCl2 and H3PO4, employing a spraying method instead of soaking, which was followed by drying, and 3) carbonisation in a furnace at the required temperature. The use of activation reagents involved the determination of an appropriate concentration, with optimum concentrations determined as 0.54M, 0.625M, 1.59M and 0.73M for NaOH, KOH, ZnCl2 and H3PO4, respectively. Apart from the fibre acti-vation, temperature and activation time were also important parameters that were optimised. A response surface methodology was used to design a set of experiments that provided the optimum temperature and activation time. From the input variables, the Expert design soft- ware generated experimental runs (n = 13) for each fibre activation reagent used with a tem-perature range of 450°C to 933°C being assessed for carbonisation time of between 17 to 208 minutes. ACF activated with KOH (0.54 M) and characterised by micropores with the highest surface area achieved being 1285.8 m2/g in comparison with Granular activated car-bon (Ounas et al., 2009) with an average surface area range of 1000 to 1100 m2/g. This sur-face area was measured using Dubinin-Astakhov isotherm with CO2 at 273 K. The physical characteristics of the ACF were analysed using a Scanning Electron Microscope to ascertain the integrity of the fibres. PFOA and PFOS were analysed using a solid phase extraction (SPE) method fol-lowed by analysis using a liquid chromatography/tandem mass spectrometer (SPE-LC/MS/MS). The water sample volume used for extraction was 60 mL. The instrument used was an HPLC - Ultimate 3000 Dionex HPLC system and MS model - Amazon SL Ion Trap, with the following MS/MS operational conditions and ion mode: MS Interface → ESI; dry temp → 350C; nebulising pressure → 60 psi; dry gas flow → 10 L/min; ionisation mode → negative; capillary voltage → +4500V; end plate offset → −500V, while the separation col-umn was a Waters Sunfire C18, 5 μm, 4.6 × 150 mm column (supplier: Waters, Dublin, Ire-land), with an operational temperature of 30C. Initially, adsorption studies (n = 48) using sonication (20 kHz) in batch systems indi-cated efficient removal of PFOA and PFOS within 120 min, with numerous samples (n = 14) achieving complete removal for both PFOA and PFOS. The minimum removal rates ob-served were 65.55% for PFOA and 95.92% for PFOS. From the ACF samples in which high-est removal rates were achieved, a number (n = 3) of the ACF samples were selected for surface characterisation. Based on the sonication in the previous experiments, an electro-physico-chemical adsorption regime was designed, to facilitate the rapid adsorption of PFOS and PFOA from contaminated drinking water in an electrolytic cell. In these experiments, si-multaneous sonication and electrolysis were used. A comparison was made between ACF produced in this study and the commercial activated carbon. The result revealed that adsorp-tion of PFOA and PFOS on ACF was a monolayer adsorption type phenomenon and had the best fit using a Freundlich isotherm compared with the Langmuir isotherm. Adsorption of PFOA and PFOS on the commercial AC presented a multilayer adsorption type of isotherm fit with the Langmuir isotherm having the best fit compared with the Freundlich isotherm.
27

The protection of water sources in developing countries

Crouse, Anton January 1986 (has links)
Thesis (Diploma (Civil Engineering))--Cape Technikon, 1986. / In rural areas in Southern Africa a nearby stream or spring is a village or kraal 's main water supply. The majority of these elementdry water sources are polluted. In this project the health hazard of polluted water and methods to protect water sources from pollution are discussed. The project consists of a report of fieldwork done in Southern Kwazula and compiling from the results a Technical Paper on water source protection.
28

Contaminação de agrotóxicos na água para consumo humano no RS : avaliação de riscos, desenvolvimento e validação de método empregando SPE e LC-MS/MS

Zini, Luciano Barros January 2016 (has links)
Os agrotóxicos, quando presentes na água, são definidos como micropoluentes: mesmo em baixas concentrações, conferem à água características de toxicidade. Aponta-se o RS como o quarto estado do Brasil com maior volume de vendas anuais de agrotóxicos, chegando a mais de 50 mil toneladas por ano. Desde 2014 está em vigência no território gaúcho uma portaria estadual que acrescenta a exigência de 46 parâmetros de agrotóxicos no padrão de potabilidade da água, além dos 27 já exigidos pela portaria nacional. Neste trabalho, 89 pesticidas foram avaliados conforme três métodos teóricos de predição de risco de contaminação em mananciais subterrâneos e superficiais: índice Ground Ubiquity Score (GUS), método Screening da USEPA e método de GOSS, baseados nas propriedades físico-químicas dos pesticidas. Nos anos de 2015 e 2016, foram realizadas 143 coletas de água para consumo humano em 45 municípios da bacia hidrográfica do Alto Jacuí (G-50), a que possui a maior taxa de aplicação de agrotóxicos do estado, para análises de vigilância através de laboratório contratado, envolvendo os 89 pesticidas presentes na portaria nacional e estadual. Em paralelo, 183 pesticidas presentes em uma solução-padrão foram empregados no desenvolvimento de um novo método de análise multiresíduos, com etapas de pré-tratamento por filtração seguidas por extração em fase sólida e LC-MS/MS, aplicada para os três maiores municípios da G-50 (Carazinho, Soledade e Cruz Alta) em amostras de água bruta e tratada, durante quatro períodos de aplicação de agrotóxicos dos principais cultivos agrícolas da região. Dos pesticidas mencionados nas portarias nacional e estadual, 12 foram classificados com o maior risco de contaminação tanto em água superficial e subterrânea de acordo com os três métodos teóricos empregadas. Nas análises de vigilância foi detectado permetrina em Carazinho e alaclor em Espumoso. No método desenvolvido, 75 pesticidas foram validados de acordo com os critérios propostos e atingiram limites de detecção (LD) e limites de quantificação (LQ) que variaram de 10 a 300 ng L-1. Na aplicação do método nas coletas dos três municípios da G-50 não houve detecção de nenhum pesticida. / Agrochemicals, when present in water, are defined as micropollutants, thus giving the water toxic characteristics, even at low concentrations. The Rio Grande do Sul state in Brazil was found to rank fourth in annual agrochemical sales in the country, surpassing 50 thousand tons per year. A state regulation in effect in the RS state since 2014 requires the inclusion of 46 new agrochemical parameters concerning the standards for potable drinking water, in addition to 27 existing parameters mandated by national ordinance. Seventy-five pesticides were evaluated based on three theoretical methodologies of contamination risk prediction in underground and surface water sources, by measuring the physicochemical properties of pesticides: GUS index, USEPA screening method and Goss method. In 2015 and 2016, 143 water samples were collected from sources of potable water in 45 municipalities located in the Alto Jacuí river basin, a region which has the highest pesticide application rate in the RS state. A private laboratory analyzed samples from 89 pesticides present in the national and state regulation. Paralely, 183 pesticides were evaluated by a new multi-residue analysis method. Filtration was conducted in the pre-treatment steps, followed by a solid phase extraction liquid chromatography coupled with mass spectrometry analysis (SPE-LC-MS/MS) of raw and treated water samples from the three largest G-50 municipalities (Carazinho, Soledade and Cruz Alta), during the four pesticide application periods of the main crops cultivated in the region. Twelve pesticides were classified as of high risk in terms of contamination for both surface and groundwater, in accordance with the three theoretical methodologies implemented. During analysis of the surveillance data collected, the pesticides permethrin and alachlor were found in Carazinho and Espumoso, respectively. Through the methodology developed, 75 pesticides were evaluated according to the criteria proposed, reaching lower detection limit (LD) and quantification limit (LQ) ranging from 10 to 300 ng L-1, respectively. During the implementation of the methodology for sample collections in the three G-50 municipalities, no pesticides were detected.
29

Qualidade microbiológica do Brycon microleps (Piraputanga) capturado na Bacia do Rio Cuibá e de cultivo no Estado do Mato Grosso

MELLO, Cassia Aldrin de 01 August 2008 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-08-02T13:31:09Z No. of bitstreams: 1 Cassia Aldrin de Melo.pdf: 1765038 bytes, checksum: 9f36b806c20bd8ef7b5100847812da9b (MD5) / Made available in DSpace on 2016-08-02T13:31:09Z (GMT). No. of bitstreams: 1 Cassia Aldrin de Melo.pdf: 1765038 bytes, checksum: 9f36b806c20bd8ef7b5100847812da9b (MD5) Previous issue date: 2008-08-01 / Cuiabá river basin, in Mato Grosso State is one of means river receivers of domestic sewage and industries effluents, for them, fishes captured can become contaminated and to be a dangerous to consumer, being rasing of fishes capitivity a viable alternative to provide better quality fish. Specimes of Brycon microleps (piraputanga) captured both from the captivity and from the river on region were studied microbiologically about the mesophiles, total and termtolerants coliforms, Aeromonas and Salmonella, on rain season, and dry season. About specimes were collected liver and encephalo, and to the comparation of values were used the test of correlation of Spearman and the Kolmogorov-Smirnov test. It was verified the sazonality effect (month of collection) over the counting of mesophile, termtolerants coliforms and Aeromonas, at both fish obtained from captivity and river. Higer contamination were observed in finish of dry season and all dry season, then, at most months hots, between August and March. The isolates were A. hydrophila and A. caviae from captivity fishes and A. sobria and A. hydrophila from river fishes, and a relationship was observed between the Aeromonas total number and the coliforms level, in other words, as higher the level of coliforms in sample, higher they were the Aeromonas spp. countings, being the high countings and the low or null, verified in the same months. Salmonella spp. was isolated at one river sample and one of captivity sample. Escherichia coli was isolated in both the fishes, of indicative that some way the water of the two atmospheres was polluted with feces. It was verified that the probability of contamination by mesophiles occurrence in river collected fish is the same as captivity ones (P≥0,05). / A bacia do rio Cuiabá no estado de Mato Grosso é uma das principais receptoras de esgotos domésticos e industriais e por isto, os peixes nela capturados podem estar contaminados e representar perigo ao consumidor, sendo a criação de peixes em cativeiro uma alternativa para a obtenção de peixes microbiologicamente melhor. Exemplares de Brycon microleps (piraputanga) oriundos do rio Cuiabá e de cultivo na região foram analisados quanto à bactérias mesófilas, coliformes, Aeromonas e Salmonella, nos meses de chuva e seca. Dos exemplares foram utilizados fígado e encéfalo, e para a comparação dos dados utilizou-se a correlação de Spearman e o teste de Kolmogorov-Smirnov. Verificou-se o efeito da sazonalidade (mês de coleta) sobre a contagem de bactérias mesófilas, coliformes termotolerantes e Aeromonas, tanto em peixes capturados no rio como nos cultivados, sendo as maiores contagens observadas no final do período seco e no início do período chuvoso, ou seja, nos meses mais quentes do ano, entre agosto e março. Foram isoladas A. hydrophila e A. caviae dos peixes de viveiro e A. sobria e A. hydrophila dos peixes do rio e observou-se uma relação entre a contagem de Aeromonas e coliformes, ou seja, quanto maior a contagem de coliformes da amostra maiores foram as contagens de Aeromonas. A Salmonella spp. foi isolada de uma amostra de rio e uma de viveiro. Escherichia coli foi isolada nos peixes de rio e de viveiro, indicando que a água dos ambientes estava contaminada com fezes. Verificou-se que a probabilidade de ocorrência da contaminação por mesófilos em peixes capturados no rio, é a mesma nos obtidos em cultivo (P≥0,05).
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Sazonalidade geoquimica em aguas intersticiais, superficiais e sedimentos estuarianos de Cubatão (SP), impactados por atividades industriais / Seasonal geochemistry in interstitial and overlying water and estuarine sediments from Cubatão (SP), impacted by industrial activities

Gonçalves, Winston Fernando de Lima 13 August 2018 (has links)
Orientadores: Wanilson Luiz Silva, Wilson T. V. Machado / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-13T05:59:28Z (GMT). No. of bitstreams: 1 Goncalves_WinstonFernandodeLima_M.pdf: 1499014 bytes, checksum: 5c07da002115d9b89a6193825e176d9f (MD5) Previous issue date: 2009 / Resumo: Este trabalho apresenta concentrações sazonais de elementos maiores, menores e traço em testemunhos de sedimentos e águas intersticiais (água de poro) e de superfície do estuário do rio Morrão, situado na porção NE do sistema estuarino de Santos-Cubatão (Estado de São Paulo). Matéria orgânica na fase sólida e algumas espécies químicas como Cl-, F-, NH4+, NO2 -, NO3 -, PO4 3- e SO4 2- também são reportadas nas águas intersticiais e de superfície e discutidas em termos do ambiente físico-químico (pH, Eh e salinidade). O objetivo maior foi avaliar o risco de biodisponibilidade de metais e metalóides. A água foi amostrada por diálise in situ, usando coletores que realizam difusão, comumente chamados peepers. A região de estudo forma um complexo ambiente, onde indústrias (desde a década de 1950) coexistem com uma área do bioma Mata Atlântica e ecossistema de manguezal. Os sedimentos coletados no verão e inverno de 2007 foram silte-argilosos (lamosos), com elevadas concentrações de matéria orgânica (8,8 a 14,2%). As águas do verão (intersticial e superficial) exibiram maior salinidade e pH em relação às águas de inverno. Em contraste, os valores de potencial redox foram maiores no inverno, mostrando condições mais redutoras durante o verão. Concentrações de NO2 -, NO3 -, PO4 3- foram abaixo do limite de detecção instrumental após a diluição da amostra em 50X, enquanto Cl- e F- (este último com forte influência industrial) foram espécies que apresentaram maiores concentrações no inverno e verão, respectivamente. O conteúdo de SO4 2- foi maior nas águas de inverno (intersticial e superficial) em comparação com as águas de verão, sugerindo que sulfato redução deve ser o processo dominante pelo qual a matéria orgânica do sedimento é metabolizada durante a estação quente e úmida (mais redutora). Em adição, amônio apresentou maior concentração no verão, implicando no decréscimo dos níveis de Eh e condições mais alcalinas. Alumínio, Si, P e Fe foram fortemente concentrados nos sedimentos, mas mostraram baixas concentrações nas águas intersticiais e de superfície, devido às respectivas baixas solubilidades nas condições físico-químicas do estuário investigado. Variabilidade sazonal é indicada no presente estudo para alguns elementos (e.g. As, Ni e Zn), incluindo sedimentos e águas intersticiais e de superfície, como resultado das variações de Eh e pH do ambiente. Elevadas concentrações de sulfetos de ferro nos sedimentos parecem tamponar o sistema, promovendo a precipitação de sulfetos menos solúveis (diminuindo a concentração de As, Ni e Zn na água) / Abstract: This work presents the seasonal concentrations of major, minor and trace elements in sediment cores and interstitial (pore water) and overlying surface waters of the Morrão river estuary located in the northeast part of the Santos-Cubatão estuarine system, State of São Paulo, Southeast Brazil, in order to discuss the metal bioavailability. Organic matter content is shown in the solid phase, and some chemical species such as Cl-, F-, NH4+, NO2 -, NO3 -, PO4 3- and SO4 2- also are reported in interstitial and overlying waters. Geochemistry data are discussed in terms of the physico-chemical environment (pH, redox potential and salinity). Water was sampled by in-situ dialysis using diffusion-type pore water samplers, commonly called "peepers". The study region forms a vast environmental complex where industries (since 1950s) coexist with an area of Atlantic rain forest and mangrove systems. The sampled sediments in summer/2007 and winter/2007 were muddy, with organic matter content ranging between 8.8% and 14.2%. The summer waters (interstitial and overlying) exhibited higher salinity and pH values compared to winter waters. In contrast, redox potential values were higher in winter, showing more reducing conditions during summer. Concentrations of NO2 -, NO3 - and PO4 3- were below the instrumental limit of detection after a 1/50 dilution with deionized water, while Cl- and F- (the latter with strong industrial influence) were dominant species in winter and summer waters, respectively. The SO4 2- content was higher in winter waters (interstitial and overlying) in comparison with summer waters, suggesting that sulfate reduction must be the dominant process by which sediment organic matter is metabolized during the hot and humid season. In addition, ammonium concentrations were highest in summer, implicating in decrease of Eh levels and more alkaline conditions. Aluminum, Si, P, and Fe were strongly concentrated in sediments, but showed relative low values in both interstitial and overlying waters due to the respective low solubility in the physico-chemical conditions of the Morrão river estuary. Seasonal variability is indicate in the present study to some elements (e.g. As, Ni and Zn), including sediments and interstitial and overlying waters, as a result of the dominant Eh and pH conditions. High iron sulfide concentrations in the sediments seem to be a buffer, controlling the precipitation of less soluble sulfides. / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências

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