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The use of diatoms to indicate water quality in wetlands : A South African perspective / by Malebo D. MatlalaMatlala, Malebo Desnet January 2010 (has links)
In a semi-arid country like South Africa, the availability and quality of water has always
played an important part in determining not only where people can live, but also their
quality of life. The supply of water is also becoming a restriction to the socio-economic
development of the country, in terms of both the quality and quantity of what is available.
Thus different monitoring techniques should be put in place to help inform the process of
conserving this precious commodity and to improve the quality of what is already
available.
Water quality monitoring has traditionally been by the means of physico-chemical
analysis; this has more recently been augmented with the use of biomonitoring techniques.
However, since the biota commonly used to indicate aquatic conditions are not always
present in wetlands; this study tested the use of diatoms as bio-indicators in wetlands.
Diatom samples were collected from thirteen wetlands in the Western Cape Province, and
cells from these communities were enumerated and diatom ?based indices were calculated
using version 3.1 of OMNIDIA. These indices were useful for indicating water quality
conditions when compared to the measured physico-chemical parameters. In addition,
most diatom species found were common to those found in riverine environments, making
the transfer of ecological optima possible.
The objective of the study was to provide a preliminary diatom-based index for wetlands,
however, given the relatively small study area and the strong bias towards coastal wetlands
it was deemed inadvisable to construct such an index, instead several indices are
recommended for interim use until further research that more comprehensively covers
wetlands in South Africa has been conducted. It is thus the recommendation of this study
that more data is collected for comparison to other wetlands and that in the interim, indices
such as SPI be applied for routine biomonitoring of these environments. / Thesis (M.Sc. (Botany))--North-West University, Potchefstroom Campus, 2010.
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The use of diatoms to indicate water quality in wetlands : A South African perspective / by Malebo D. MatlalaMatlala, Malebo Desnet January 2010 (has links)
In a semi-arid country like South Africa, the availability and quality of water has always
played an important part in determining not only where people can live, but also their
quality of life. The supply of water is also becoming a restriction to the socio-economic
development of the country, in terms of both the quality and quantity of what is available.
Thus different monitoring techniques should be put in place to help inform the process of
conserving this precious commodity and to improve the quality of what is already
available.
Water quality monitoring has traditionally been by the means of physico-chemical
analysis; this has more recently been augmented with the use of biomonitoring techniques.
However, since the biota commonly used to indicate aquatic conditions are not always
present in wetlands; this study tested the use of diatoms as bio-indicators in wetlands.
Diatom samples were collected from thirteen wetlands in the Western Cape Province, and
cells from these communities were enumerated and diatom ?based indices were calculated
using version 3.1 of OMNIDIA. These indices were useful for indicating water quality
conditions when compared to the measured physico-chemical parameters. In addition,
most diatom species found were common to those found in riverine environments, making
the transfer of ecological optima possible.
The objective of the study was to provide a preliminary diatom-based index for wetlands,
however, given the relatively small study area and the strong bias towards coastal wetlands
it was deemed inadvisable to construct such an index, instead several indices are
recommended for interim use until further research that more comprehensively covers
wetlands in South Africa has been conducted. It is thus the recommendation of this study
that more data is collected for comparison to other wetlands and that in the interim, indices
such as SPI be applied for routine biomonitoring of these environments. / Thesis (M.Sc. (Botany))--North-West University, Potchefstroom Campus, 2010.
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Qualidade da água utilizada para consumo em escolas no município de São Carlos-SPScuracchio, Paola Andressa [UNESP] 15 December 2010 (has links) (PDF)
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scuracchio_pa_me_arafcf.pdf: 218891 bytes, checksum: c8aae0d323ca8f97bd9a60baa02de3d6 (MD5) / Universidade Estadual Paulista (UNESP) / Sabe-se da importância de se tratar a água destinada ao consumo humano, pois, é capaz de veicular grande quantidade de contaminantes físico-químicos e/ou biológicos, cujo consumo tem sido associado a diversos problemas de saúde. Assim, é necessário saber se a qualidade da água destinada ao consumo humano, responde as exigências da legislação. O objetivo desta pesquisa foi avaliar a qualidade da água que abastece as escolas e creches municipais da cidade de São Carlos – SP. Foram coletadas 186 amostras de água, em três pontos distintos: rede, reservatório e filtro. Para análise de coliformes totais e coliformes fecais/E. coli utilizou-se a técnica de substratos cromogênicos/Colilert; para contagem de bactérias heterotróficas foi utilizada a técnica de cultivo em profundidade; para determinação do pH adotou-se leitura direta no pHâmetro; para determinação de flúor foi utilizado o método SPANDS; para determinação de cloro utilizou-se o método DPD; para determinação de turbidez foi utilizado o método nefelométrico e para determinação da cor o método colorimétrico. Para coliformes fecais/E.coli apenas uma amostra do filtro apresentou positividade. Para coliformes totais, sete amostras (22,5%) da rede, seis (19,3%) do reservatório e seis (19,3%) do filtro apresentaram contaminação na primeira colheita e sete (22,5%) amostras da rede, três (9,6%) do reservatório e sete (22,5%) do filtro na segunda coleta. Para bactérias heterotróficas uma amostra da rede, uma do reservatório e 13 (41,9%) do filtro apresentaram contagens acima de 500UFC/ml na primeira coleta e três (9,6%) amostras da rede e do reservatório e 14 (45,1%) do filtro na segunda coleta. Para pH, cinco amostras (16,1%) da rede e uma do filtro não atenderam ao padrão exigido pela legislação na primeira coleta e sete amostras (22,6%) da rede na segunda coleta... / Today, we know the importance of treating water for human consumption, therefore, is capable of conveying large amounts of physical and chemical contaminants and / or biological agents, whose consumption has been associated with several health problems. Thus, it is necessary to know if the quality of water intended for human consumption, answers the requirements of the law. The aim of this study was to evaluate the quality of water supply schools and day care centers of São Carlos - SP. We collected 186 samples of water, on three points: network, tank and filter. For analysis of total coliform and fecal coliform / E. coli we used the technique of chromogenic substrates / Colilert; for heterotrophic bacterial count technique was used to grow in depth, to determine pH reading was adopted in direct pHâmetro; for determination of fluoride, the method SPANDS; to determine chlorine used the DPD method, for determination of turbidity nephelometric method was used to determine the color and colorimetric method. For fecal coliform / E.coli only one sample was positive filter. For total coliforms, seven samples (22.5%) of the network, six (19.3%) of the tank and six (19.3%) of the filter was contaminated in the first harvest and seven (22.5%) samples of the network three (9.6%) of the reservoir and seven (22.5%) of the filter in the second collection. Heterotrophic bacteria from a sample network, a tank and 13 (41.9%) of the filter had counts above 500UFC/ml the first harvest and three (9.6%) samples of the network and the reservoir and 14 (45, 1%) of the filter in the second harvest. For pH, five samples (16.1%) of the network and a filter did not meet the standard required by legislation in the first harvest and seven samples (22.6%) of the net in the second harvest. For fluoride 27 (87.0%) of the network, 24 (77.4%) of the reservoir and 25 (80.6%) were outside of the filter pattern in the first... (Complete abstract click electronic access below)
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Qualidade da água de múltiplos usos na microrregião de Itapecuru-Mirim-MAAlves, Lúcia Maria Coêlho [UNESP] 07 June 2010 (has links) (PDF)
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alves_lmc_dr_jabo.pdf: 5616819 bytes, checksum: 4a53256d90bbcf403f575125bc5a14c7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A água é um recurso natural indispensável à vida, é essencial à promoção social, à produção de alimentos e ao desenvolvimento econômico. Com o objetivo de se avaliar a qualidade microbiológica e físico-química de águas subterrâneas e superficiais na microrregião de Itapecuru-Mirim-MA foram colhidas 172 amostras de água, sendo 86 no período chuvoso (março a maio) e 86 amostras no período de estiagem (agosto a outubro). Destas, 39 amostras eram águas consumidas em residências rurais procedentes de poços artesianos, poços rasos, fontes naturais e Rede Publica de Abastecimento, 05 eram de uso doméstico, 08 de lavagem dos tetos das vacas; 02 de uso em laticínios, 01 de uso em matadouro, 01 de fábrica de polpas de frutas, 18 de bebedouros dos animais, 09 águas de uso em piscicultura e 03 de irrigação de hortaliças. Foram analisados parâmetros microbiológicos e físico-químicos e aplicado um questionário fechado contendo perguntas objetivas para se avaliar o nível de conhecimento das pessoas quanto à qualidade da água usada ou consumida e mapeado geograficamente os pontos de colheitas. Os resultados das análises microbiológicas e físico-químicas identificaram 52 (66,66 %) amostras de água de consumo humano em desacordo com os padrões microbiológicos e 23 (29,48%) em desacordo com os parâmetros físico-químicos, nove (90%) amostras de água de uso doméstico não atenderam aos padrões microbiológicos, enquanto seis (60%) não o foram para os padrões físico-químicos, para água de lavagem dos tetos evidenciaramse 13 (81,25%) e 10 (62,50%) amostras, respectivamente, fora dos padrões microbiológicos e físico-químicos vigentes. Não foi constatada contaminação microbiológica nem físico-química para água de uso em laticínio e em fábrica de polpa de frutas. Referente à água de uso em matadouro, uma (50%) amostra não atendeu aos padrões... / Water is a natural resource essential for life, it is essential to social promotion, food production and economic development. In order to evaluate the microbiological and physical chemistry quality of groundwater and surface water in the municipality of Itapecuru-Mirim-MA were collected 172 water samples, including 86 in the rainy season (March-May) and 86 samples in the dry weather period (August- October). From these total, 39 samples were water consumed in rural residences coming from shallow water wells, artesian water wells, natural sources and public water supply, 05 were domestic water, 08 from teat washings of cows; 02 for use in dairy products, 01 from the slaughterhouse, 01 from a factory fruit pulps, 18 from animal drinking fountains, 09 water samples used for pisciculture and 03 from vegetables irrigation. They were all analyzed for the microbiological and physical-chemical parameters. A close questionnaire with objective questions was also applied to evaluate the awareness level of people about the water quality used or consumed and the crops points were geographically mapped. The microbiological and physical-chemical results identified 52 (66,66%) water samples for human consumption in discordance with the microbiological standards and 23 (29,48%) in discord to the physical-chemical parameters, nine (90%) water samples for domestic use did not attend to the microbiological standards, while six (60%) were not for the physical-chemical parameters. The teat washing water results showed that 13 (81,25%) and 10 (62,50%) samples, respectively, were out of the microbiological and physical-chemical actual patterns. It was not detected microbiological contamination of water used in the dairy and in the fruit pulp factory. Referring to the water used in the slaughterhouse, one (50%) sample did not attend to the microbiological patterns, but all samples attended to the physical-chemical...(Complete abstract click electronic access below)
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Propriétés physico-chimiques et fonctionnelles des gommes hydrocolloïdes des écorces de Triumfetta cordifolia et Bridelia thermifolia / Functionnal and physico-chemical properties of hydrocolloids gums of the Triumfetta cordifolia and Bridelia thermifolia barks.Saidou, Clément 19 November 2012 (has links)
Triumfetta cordifolia et Bridelia thermifolia sont deux arbustes de la région tropicale d'Afrique dont les gommes extraites des écorces fraîches ou séchées sont confinées aux utilisations traditionnelles, notamment dans la cuisine (propriétés d'épaississement et d'aromatisation des sauces, d'amélioration de la texture des pâtisseries) et dans le procédé de décantation des bières traditionnelles de sorgho (bili-bili). Dans le but d'identifier la nature des gommes responsables de ces propriétés et d'évaluer leur potentiel de valorisation, la composition chimique (protéines, polysaccharides, fibres et minéraux) des écorces a été déterminée. Les gommes ont été extraites, caractérisées sur le plan chimique (composition en monosaccharides et en minéraux) et physique (comportement rhéologiques des extraits, poids moléculaire, viscosité intrinsèque et rayon de giration) et l'effet combiné des facteurs du milieu (température, pH, et concentration saline (NaCl, KCl, CaCl2 et MgCl2)) influençant la viscosité a été analysé selon un plan composite centré. Enfin, un essai d'application de ces gommes dans la préparation des beignets de maïs et de sorgho a été réalisé. Les résultats des analyses chimiques montrent une prédominance des polysaccharides dans les écorces (52 et 55% respectivement pour B. thermifolia et T. cordifolia) et dans les extraits (76 et 80% respectivement pour B. thermifolia et T. cordifolia), avec des teneurs 5 à 8 fois supérieures à celles des protéines. Ce qui permet de considérer que ces polysaccharides sont responsables des propriétés physiques d'épaississement exprimées par les extraits. Ces propriétés ne sont aucunement modifiées par le séchage des écorces. Les polysaccharides des extraits sont constitués principalement de rhamnose (24,51%), de galactose (15,23%), d'acides glucuronique (25,51%) et galacturonique (20,23%). La présence significative d'acides uroniques justifie la persistance des minéraux dans les extraits purifiés. Les masses moléculaires moyennes des polysaccharides sont de 6,14 x106 et 3,58 x106Da respectivement pour T. cordifolia et B. thermifolia. Sur le plan physique, leurs viscosités intrinsèques et leur rayon de giration sont relativement élevés (18,33dl/g et 269,6nm pour T. cordifolia; 17,98dl/g et 217,8nm pour B. thermifolia). La cinétique de séchage des écorces de T. cordifolia et B. thermifolia se déroule en deux périodes cinétiques représentées par deux constantes de séchage k1 et k2 qui augmentent avec la température de séchage. La viscosité des extraits diminue pour des températures de séchage des écorces au-délà de 70°C. Cette baisse de viscosité des extraits serait plus le résultat d'un changement de conformation des polysaccharides que de leur dégradation. L'étude du comportement rhéologique de ces polysaccharides traduit un comportement rhéofluidifiant, viscoélastique, peu thixotrope et avec des contraintes seuil d'écoulement comprises entre 0,2 et 5Pa et entre 0,5 et 1Pa respectivement pour T. cordifolia et B. thermifolia à des concentrations comprises entre 0,52 et 0,82g/l. La température et les cations monovalents (K+ et Na+) ont un effet dépresseur sur la viscosité des gommes tandis que les pHs faiblement acide et alcalin et les cations divalents (Ca2+ et Mg2+) l'augmentent. L'effet combiné de ces facteurs sur la viscosité des gommes se décrit de façon satisfaisante par un modèle de second degré. L'analyse des interactions entre les facteurs de variation (définit dans le modèle) met en évidence, pour chaque facteur, une plage de valeurs pour lesquelles il contribue à l'obtention d'une zone de viscosités optimales et offre sur le plan pratique une gamme de choix des niveaux de variables en fonction du niveau de viscosité voulue. L'incorporation d'extraits de T. cordifolia (3,5 g/l) et B. thermifolia (11 g/l) dans la farine de maïs ou de sorgho, contribue de façon significative à l'amélioration du gonflemen / Triumfetta cordifolia and Bridelia thermifolia are two shrubs of tropical Africa whose gums extracted from fresh or dried barks are confined to traditional uses, particularly in the kitchen (thickening and flavoring properties in sauces and improvement of the texture of bakery ptoducts) and in the decantation process of the sorghum based traditionnal beer (bili-bili). In order to identify the nature of the gums responsible for these properties and assess their potentials for valorization, the chemical composition (proteins, polysaccharides, minerals and fiber) of barks was determined. The gums were extracted, and characterized for their chemical (monosaccharide composition and minerals) and physical (rheological behavior of extracts, molecular weight, intrinsic viscosity and radius of gyration) properties. Then, the combined effects of environmental factors (temperature, pH and salt concentration [NaCl, KCl, CaCl2 and MgCl2]) influencing the viscosity was analyzed using a central composite design. Finally application test of these gums in preparing doughnuts from maize and sorghum flour was carried out. The results of chemical analyzes showed that polysaccharides dominated in the barks (52 and 55% respectively for B.thermifolia and T. cordifolia) and in extracts (76 and 80% respectively for B.thermifolia and T. cordifolia), with levels 5-8 times higher than those of proteins. This allowed to hypothesize that these polysaccharides are responsible for the thickening properties demonstrated by the extracts. These properties are not be affected by the drying of the bark. The polysaccharides of the extracts are mainly composed of rhamnose (24.51%), galactose (15.23%), glucuronic acid (25.51%) and galacturonic acid (20.23%). The significant presence of uronic acids justifies the persistence of minerals in the purified extracts. The molecular weights of polysaccharides are 6.14 x106 and 3.58x106 Da, respectively for T. cordifolia and B. thermifolia. On the physical level, their intrinsic viscosities and their gyration radius are relatively high (18.33 dl/g and 269.6 nm for T. cordifolia; 17.98 dl/g and 217.8 nm for B. thermifolia). The drying kinetics for barks of T. cordifolia and B. thermifolia presents two falling rate periods represented by two kinetic constants k1 and k2, which increase with increasing drying temperature. Viscosity of extracts decreases when barks are dried beyond 70°C. This may be probably the consequence of a conformational change of polysaccharides than the result of their degradation. The study of the rheological behavior of these polysaccharides indicates a shear thinning, viscoelastic and weak thixotropic behavior, with flowing pressures yield point between 0.2 and 5Pa and between 0.5 and 1Pa, respectively for T. cordifolia and B. thermifolia, at concentrations between 0.52 and 0.82 g/l. Temperature and monovalent cations (K+ and Na+) have a depressant effect on viscosity of gums, while weakly acidic and alkaline pH and divalent cations (Ca2+ and Mg2+) increase it. The combined effect of these factors on the viscosity of gums is satisfactorily described by a second degree model. Analysis of interactions between factors of variation shows, for each factor, a range of values for which it contributes to the achievement of a zone of optimal viscosity. This zone offers a practical range for the choice of variable levels, depending on the desired viscosity. The incorporation of extracts of T. cordifolia (3.5 g/l) and B. thermifolia (11 g/l) in the maize or sorghum flour, improves significantly the swelling of the dough. The doughnuts obtained after baking are, from organoleptic point of view, comparable to wheat doughnuts.
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Qualidade da água utilizada para consumo em escolas no município de São Carlos-SP /Scuracchio, Paola Andressa. January 2010 (has links)
Orientador: Adalberto Farache Filho / Banca: João Bosco Faria / Banca: Clovis Wesley de Oliveira Souza / Resumo: Sabe-se da importância de se tratar a água destinada ao consumo humano, pois, é capaz de veicular grande quantidade de contaminantes físico-químicos e/ou biológicos, cujo consumo tem sido associado a diversos problemas de saúde. Assim, é necessário saber se a qualidade da água destinada ao consumo humano, responde as exigências da legislação. O objetivo desta pesquisa foi avaliar a qualidade da água que abastece as escolas e creches municipais da cidade de São Carlos - SP. Foram coletadas 186 amostras de água, em três pontos distintos: rede, reservatório e filtro. Para análise de coliformes totais e coliformes fecais/E. coli utilizou-se a técnica de substratos cromogênicos/Colilert; para contagem de bactérias heterotróficas foi utilizada a técnica de cultivo em profundidade; para determinação do pH adotou-se leitura direta no pHâmetro; para determinação de flúor foi utilizado o método SPANDS; para determinação de cloro utilizou-se o método DPD; para determinação de turbidez foi utilizado o método nefelométrico e para determinação da cor o método colorimétrico. Para coliformes fecais/E.coli apenas uma amostra do filtro apresentou positividade. Para coliformes totais, sete amostras (22,5%) da rede, seis (19,3%) do reservatório e seis (19,3%) do filtro apresentaram contaminação na primeira colheita e sete (22,5%) amostras da rede, três (9,6%) do reservatório e sete (22,5%) do filtro na segunda coleta. Para bactérias heterotróficas uma amostra da rede, uma do reservatório e 13 (41,9%) do filtro apresentaram contagens acima de 500UFC/ml na primeira coleta e três (9,6%) amostras da rede e do reservatório e 14 (45,1%) do filtro na segunda coleta. Para pH, cinco amostras (16,1%) da rede e uma do filtro não atenderam ao padrão exigido pela legislação na primeira coleta e sete amostras (22,6%) da rede na segunda coleta... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Today, we know the importance of treating water for human consumption, therefore, is capable of conveying large amounts of physical and chemical contaminants and / or biological agents, whose consumption has been associated with several health problems. Thus, it is necessary to know if the quality of water intended for human consumption, answers the requirements of the law. The aim of this study was to evaluate the quality of water supply schools and day care centers of São Carlos - SP. We collected 186 samples of water, on three points: network, tank and filter. For analysis of total coliform and fecal coliform / E. coli we used the technique of chromogenic substrates / Colilert; for heterotrophic bacterial count technique was used to grow in depth, to determine pH reading was adopted in direct pHâmetro; for determination of fluoride, the method SPANDS; to determine chlorine used the DPD method, for determination of turbidity nephelometric method was used to determine the color and colorimetric method. For fecal coliform / E.coli only one sample was positive filter. For total coliforms, seven samples (22.5%) of the network, six (19.3%) of the tank and six (19.3%) of the filter was contaminated in the first harvest and seven (22.5%) samples of the network three (9.6%) of the reservoir and seven (22.5%) of the filter in the second collection. Heterotrophic bacteria from a sample network, a tank and 13 (41.9%) of the filter had counts above 500UFC/ml the first harvest and three (9.6%) samples of the network and the reservoir and 14 (45, 1%) of the filter in the second harvest. For pH, five samples (16.1%) of the network and a filter did not meet the standard required by legislation in the first harvest and seven samples (22.6%) of the net in the second harvest. For fluoride 27 (87.0%) of the network, 24 (77.4%) of the reservoir and 25 (80.6%) were outside of the filter pattern in the first... (Complete abstract click electronic access below) / Mestre
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Understanding Viscoelastic Behavior of Asphalt Binders Through Molecular Structure InvestigationJanuary 2018 (has links)
abstract: Asphalt binder is a complex viscoelastic hydrocarbon, whose performance depends upon interaction between its physical and chemical properties, both of which are equally important to the successful understanding of the material. Researchers have proposed various models linking linear viscoelastic (LVE) and microstructural parameters. However, none of these parameters provide insight into the relationship in the non- linear viscoelastic NLVE domain. The main goals of this dissertation are two fold. The first goal is to utilize the technique of Laser Desorption Mass Spectroscopy (LDMS) to relate the molecular structure of asphalt binders to its viscoelastic properties. The second goal of the study is to utilize different NLVE characterization tools and analysis procedures to get a clear understanding of the NLVE behavior of the asphalt binders. The goals of the study are divided into four objectives; 1) Performing the LDMS test on asphalt binder to develop at the molecular weight distributions for different asphalts, 2) Characterizing LVE properties of Arizona asphalt binders, 3) Development of relationship between molecular structure and linear viscoelasticity, 4) Understanding NLVE behavior of asphalt binders through three different characterization methods and analysis techniques.
In this research effort, a promising physico-chemical relationship is developed between number average molecular weight and width of relaxation spectrum by utilizing the data from LVE characterization and the molecular weight distribution from LDMS. The relationship states that as the molecular weight of asphalt binders increase, they require more time to relax the developed stresses. Also, NLVE characterization was carried out at intermediate and high temperatures using three different tests, time sweep fatigue test, repeated stress/strain sweep test and Multiple Stress Creep and Recovery (MSCR) test. For the intermediate temperature fatigue tests, damage characterization was conducted by applying the S-VECD model and it was found that aged binders possess greater fatigue resistance than unaged binders. Using the high temperature LAOS tests, distortion was observed in the stress-strain relationships and the data was analyzed using a Fourier transform based tool called MITlaos, which deconvolves stress strain data into harmonic constituents and aids in identification of non-linearity by detecting higher order harmonics. Using the peak intensities observed at higher harmonic orders, non-linearity was quantified through a parameter termed as “Q”, which in future applications can be used to relate to asphalt chemical parameters. Finally, the last NLVE characterization carried out was the MSCR test, where the focus was on the scrutiny of the Jnrdiff parameter. It was found that Jnrdiff is not a capable parameter to represent the stress-sensitivity of asphalt binders. The developed alternative parameter Jnrslope does a better job of not only being a representative parameter of stress sensitivity but also for temperature sensitivity. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2018
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Avaliação das condições higienicossanitárias e análise de parâmetros microbiológicos e físico-químicos do pescado importado no Porto de Santos/SP / Evaluation of hygienic sanitary conditions and analysis of microbiological and physico-chemical parameters of imported fish in the Santos/SP portAdriano Perrelli Pestana de Castro 09 February 2017 (has links)
Introdução - O pescado é amplamente utilizado para a produção de alimentos à base de matéria-prima de origem animal. A importação de pescado vem crescendo ano a ano, sendo o Porto de Santos/SP uma das principais rotas de entrada desse produto no país. Objetivos - Avaliar as condições higienicossanitárias de pescado importado no Porto de Santos/SP. Métodos - A pesquisa foi desenvolvida com base em duas abordagens: estudo dos requisitos obrigatórios para nacionalização do produto importado com base na legislacão vigente e trabalho desempenhado pelo Vigiagro/MAPA, assim como, estudo laboratorial. Foram coletadas 60 amostras de 30 diferentes produtos de pescado sendo cada amostra constituída por, no mínimo, 500 g do produto de uma mesma marca, lote, data de fabricação e validade. Uma parte das amostras, 30 embalagens de 500 g no mínimo, foi acondicionada em caixas isotérmicas com temperatura controlada e encaminhada para realização das análises microbiológicas. As demais 30 embalagens foram encaminhadas, sob as mesmas condições, para realização das análises físico-químicas. As análises físico-químicas e microbiológicas foram realizadas em Laboratórios credenciados no Mapa. Para produtos congelados foram realizadas as análises microbiológicas para pesquisa de Salmonella spp em 25 gramas e contagem de Staphylococcus coagulase positiva e realização das análises físico-químicas de N-BVT. Para produtos salgados refrigerados, foram realizadas análises microbiológicas para pesquisa de Salmonella spp em 25 gramas, contagem de Staphylococcus coagulase positiva e contagem de coliformes termotolerantes a 450 C, assim como, realização das análises físico-químicas de umidade e resíduo mineral fixo. Resultados - Nos produtos congelados, as análises físico-químicas para o N-BVT e as análises microbiológicas para pesquisa de Salmonella spp em 25 gramas e contagem de Staphylococcus coagulase positiva indicaram 100,0% de conformidade com a legislação vigente. Nos produtos salgados refrigerados, as análises microbiológicas para pesquisa de Salmonella spp em 25 gramas, contagem de Staphylococcus coagulase positiva e contagem de coliformes termotolerantes a 450 C também indicaram 100,0% de conformidade com a legislação vigente. Por outro lado, 100,0% das análises físico-química de umidade e 44,4% das análises físico-químicas para resíduo mineral fixo no pescado salgado resfriado estavam com valores acima da legislação vigente. Todos os produtos apresentaram documentação obrigatória e rótulo de acordo com a legislação vigente. Conclusão Embora os resultados das análises microbiológicas tenham demonstrado que os produtos estivessem próprios para o consumo, as análises físico-químicas, em específico os parâmetros referentes a umidade no pescado salgado refrigerado, não estavam de acordo com os valores determinados pela legislação vigente. A legislação sanitária vigente para importação de pescados, assim como a metodologia de inspeção e fiscalização desses produtos, se mostrou eficiente comparado aos resultados laboratoriais encontrados, com possibilidade de inclusão de novas ferramentas e análises laboratoriais visando garantir, ainda mais, as condições higiênicossanitárias e segurança alimentar. / Introduction - Seafood is widely used for the production of food based on raw materials of animal origin. The fish import has been growing year by year, and the Port of Santos / SP one of the main routes of entry of that product in the country. Objectives - To evaluate the hygienic-sanitary conditions of imported fish in the Port of Santos / SP. Methodology - The study was based up on two approaches: study of the mandatory requirements for nationalization of the imported product on the basis of current legislation and work performed by Vigiagro / MAPA, as well as laboratory study. It was collected 60 samples from 30 different products of fish each sample being composed by 500 g from the same brand, batch number, manufacturing and expiration date. A share of these samples, 30 packages of 500 g at least, was accommodated and transported in temperature-controlled isothermal box to the microbiological analysis. The remaining 30 packages were sent, under the same conditions, to physico-chemical analysis. The physico-chemical and microbiological analyzes were performed in laboratories accredited on MAPA. For frozen products were performed microbiological analyzes for Salmonella spp research in 25 g Staphylococcus and count coagulase positive and achievement of physical and chemical analysis of N-BVT. For salted products, microbiological analyzes were performed for detection of Salmonella spp in 25 g, Staphylococcus coagulase positive count and count of coliform to 450 C and physical-chemical analysis for humidity and fixed mineral residue. Results - In the frozen products, physico-chemical analysis for the N-BVT and microbiological analyzes for Salmonella spp research in 25 g and Staphylococcus coagulase positive counts indicated 100.0% of compliance with current regulation. In salted products, microbiological analyzes for Salmonella spp research in 25 g, Staphylococcus coagulase positive and coliform to 450 C counts also indicated 100.0% compliance with current legislation. On the other, 100.0% of the physico-chemical analysis of humidity and 44,4 % in the ashs physico-chemical results, in salted fish, were with higer limits established by Brazilian legislation. All products submitted mandatory documents required for import and labeling in accordance with current regulation. Conclusion - Although the results of the microbiological analyzes showed that the imported fish were apropriate for consumption, the physico-chemical analysis, in particularly the humidity parameters were not in accordance with values indicated in the current regulation. The current health regulation for the imported fish, as well as the inspection methodology and supervision of these products, was efficient compared to laboratory findings, with the possibility of adding new tools and laboratory tests to ensure even more the higienic-sanitary conditions and food safety.
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Influência do grau de etoxilação no comportamento de álcoois secunários etoxilados / The influence of ethoxylation degree in the behaviour of secondary alcohol ethoxylatesAndré Bozzo Argenton 24 April 2009 (has links)
A solubilização de solutos não iônicos através de um processo de partição entre água e a pseudo-fase micelar de tensoativos não iônicos foi estudada para álcoois secundários etoxilados com grau de etoxilação variando entre 7 e 40. Mostrou-se que o coeficiente de incorporação micelar, Ks, é independente do grau de etoxilação o que corrobora a hipótese de que a partição ocorre entre água e o núcleo hidrocarbônico da micela, que não é alterado pelo aumento do número de grupos de óxido de eteno na cabeça polar do tensoativo. O uso de relações lineares de energia livre, LSER, para a predição da capacidade de solubilização de álcoois secundários etoxilados forneceu, através de regressão múltipla linear a seguinte LSER como melhor modelo: log Ks = -0,42 + 1,21E - 1,73S -0,40A - 1,13B + 3,01V com R2 = 0,98 e valor de teste F de 1390. Nesta equação, V é o volume molar do soluto, A e B são a capacidade do soluto de atuar como doador e aceptor de pontes de hidrogênio, E é a refração molar em excesso e S representa a capacidade do soluto de interagir com o meio de solubilização através de interações do tipo dipolo-dipolo e dipolo-dipolo induzido. Mostrou-se que processos de limpeza aplicados à remoção de sujidades de tecidos e superfícies sólidas não estão correlacionados ao mecanismo de solubilização descrito por um processo de partição. A dependência da redução de tensão interfacial com o grau de etoxilação sugere que a eficiência de limpeza, para superfícies sólidas e para tecidos, está correlacionada de maneira direta, mas não linear, com a capacidade do tensoativo de concentrar-se na interface \"sujidade-solução aquosa de tensoativo\" reduzindo assim a tensão interfacial entre os dois meios. / The solubilization of non-ionic solutes via partitioning between water and the micellar pseudophase of non-ionic surfactants was evaluated for a series of secondary alcohol ethoxylates with hydrophile length varying from 7 to 40 ethylene oxide units. It was demonstrated that the micellar incorporation constant, Ks, is not dependent on the hydrophile length of the surfactant. The results obtained in this study support the hypothesis that the partitioning between water and the micellar core is not disturbed by the etheylene oxide hydrophilic groups. Linear solvation free energy relationships, LSER, were used to model the ability of the surfactants to solubilize non-ionic compounds. Multiple linear regression analysis provided the following LSER with R2 of 0.98 and F value of 1390: logK = -0,42 + 1,21E - 1,73S - 0,40A - 1,13B + 3,01V. In this LSER, V is a descriptor of solute molar volume, A and B capture the overall ability of the solute to act as a hydrogen bond donor and acceptor, E is the solute excess molar refraction and S is a descriptor of the ability of the solute to interact via dipole-dipole and dipole-induced dipole interactions with its surroundings. It was demonstrated that hard and soft surface cleaning efficiencies are not correlated with the solubilization process. It was shown, however, that the change in interfacial tension caused by the change in the hydrophile portion of the surfactants has a direct, but non-linear impact on the cleaing properties of aqueous solutions containing these surfactants.
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Influência do protocolo de secagem com álcool isopropílico na adesividade de diferentes cimentos obturadores de metacrilato à dentina radicular / Influence of the drying protocol with isopropyl alcohol on the adhesion of different methacrylate-based sealers to intraradicular dentinKleber Campioni Dias 12 April 2012 (has links)
O presente estudo teve como objetivo avaliar a influência do protocolo de secagem com álcool isopropílico à adesividade dos cimentos AH Plus, Hybrid Root Seal e Epiphany SE à dentina radicular. Oitenta raízes de caninos foram submetidas ao preparo biomecânico e distribuídas em 2 grupos de acordo com a secagem, previamente a obturação: I- Secagem cone de papel absorvente e II- Secagem com álcool isopropílico 70%,e posteriormente distribuídas em 8 grupos (n=10): IA e IIA cimento AH Plus; IB e IIB - cimento Hybrid Root Seal; IC e IIC- cimento Epiphany SE com guta percha e ID e IID cimento Epiphany SE com Resilon. Após a obturação, 80 raízes foram seccionadas transversalmente obtendo-se 3 slices de 1,0 mm de espessura para cada terço radicular. Um slice de cada terço foi submetido ao teste de push out e tipo de falha analisado por meio de lupa estereoscópica. Os dois slices restantes foram submetidos à MEV para análise da interface adesiva e superfície do material obturador. A análise de variância evidenciou haver diferença estatisticamente significante (p<0,05) entre os materiais obturadores, o protocolo de secagem do canal radicular e a interação destes fatores. AH Plus/ guta percha obteve os maiores valores médios de resistência de união (3,83 ± 0,45 MPa), sendo estatisticamente diferente (p<0,05) dos demais. O Hybrid Root SEAL/ guta percha (3,24 ± 0,46 MPa) obteve valores intermediários, sendo estatisticamente diferente dos demais (p<0,05). O cimento obturador Epiphany SE quando associado à guta percha (0,45 ± 0,10 MPa) ou ao Resilon (0,31 ± 0,09 MPa) obteve os menores valores de adesividade, sendo estatisticamente semelhantes entre si (p>0,05) e diferentes dos demais (p<0,05). O cimento AH Plus obteve os maiores valores de adesividade independente do protocolo de secagem utilizado. Na comparação entre os protocolos, o protocolo que utilizou álcool isopropílico 70% obteve maiores valores médios de adesividade. / The purpose of the present study was to evaluate the influence of the drying protocol with isopropyl alcohol on the adhesion of the sealers AH Plus, Hybrid Root Seal and Epiphany SE to intraradicular dentin. Eighty root canals of canines were subjected to biomechanical preparation and were allocated to receive one of the following drying protocols (n=40) prior to root canal filling: I- Drying with absorbent paper point and II- Drying with 70% isopropyl alcohol. Thereafter, 8 groups (n=10) were formed according to the filling material: IA and IIA AH Plus sealer; IB and IIB - Hybrid Root Seal sealer; IC and IIC- Epiphany SE sealer with gutta-percha; and ID and IID Epiphany SE sealer with Resilon. After filling, the 80 roots were sectioned transversally to obtain three 1.0-mm-thick slices from each root third. The first slice of each third was subjected to a push-out test and the failure mode was determined with a stereoscopic lens. The other two slices were prepared for SEM to examine adhesive interface and the surface of the filling materials. Analysis of variance revealed statistically significant difference (p<0.05) among the filling materials, between the root canal drying protocols as well as for the interaction of these factors. AH Plus/gutta-percha had significantly higher (p<0.05) bond strengths (3.83 ± 0.45 MPa) than the other materials. Hybrid Root SEAL/gutta-percha (3.24 ± 0.46 MPa) had intermediate values and differed significantly from the other materials (p<0.05). Epiphany SE combined with either gutta-percha (0.45 ± 0.10 MPa) or Resilon (0.31 ± 0.09 MPa) presented the lowest bond strengths without statistically significant difference (p>0.05) from each other, but with significant difference (p<0.05) from the other materials. AH Plus present the highest bond strengths regardless of the drying protocol. Comparing the two protocols, drying of root canals with 70% isopropyl alcohol was associated with the highest bond strength values to intraradicular dentin.
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