Ajustes de coeficientes integrantes de processos físicos e bioquímicos na autedepuração em curso de água de médio porte

The mathematical modeling in the simulation of self-purification capacity in lotic environment is an important tool in the planning and management of hydric resources in hydrographic basin scale. It satisfactorily deals with the self-purification process when the coefficients of physical and biochemical processes are calibrated from monitorated water quality data, which was the main focus of this study. The present study was conducted to simulate the behavior of the parameters OD, BOD5, total phosphorus, E. coli, ammonia, nitrite, nitrate and the total metals cadmium, chromium, copper, lead and zinc in the Uberabinha’s lower course (with an approximate annual growth flow between 4-35 m3/s), in a stretch of 19 km downstream of the treated effluent release by the WWTP of the city. The modelings, on the present study, show the importance of constant water quality parameters monitoration over the water course, based on the comparison of the simulations from calibrated coefficients and coefficients obtained in the literature for the period of June until November 2015. After coefficients calibration, there were good adjustments between simulated and measured data for the parameters OD, BOD, Ptotal, ammonia and nitrate and unsatisfactory adjust for the parameters nitrite and E. coli. About the total metals, the adjustments were not satisfactory on the reservoir’s vicinity of the Small Hydropower Plant Martins, due the considerable increase of the bottom sediment in lentic region. The greatest scientific contribution of this study was to calibrate the decay coefficient K and the quantification of the release by the fund S of total metals in watercourse midsize WWTP pollutant load receptor, justified by the lack of studies in the literature about the subject. For the metals cadmium, chromium, copper, lead and zinc, the borderline for K and S calibrated were: 0.0 to 13.0 day-1 and 0.0 to 1.7 g/m3.day; 0.0 to 0.9 day-1 and 0.0 to 7.3 g/m3.day; 0.0 to 25.0 day-1 and 0.0 to 1.8 g/m3.day; 0.0 to 7.0 day-1 and 0.0 to 40.3 g/m3.day; 0.0 to 30.0 day-1 and 0.0 to 70.1 g/m3.day.

Assessment of metals contamination (Cd, Pb, Ni) at the Óbidos Lagoon using Cerastoderma edule as a biomonitoring tool

A poluição marinha é um problema ambiental Mundial que afeta as constituintes bióticas e abióticas do Ecossistema. Os resultados de diversas atividades antropogénicas chegam ao meio marinho através de escorrências terrestres, industriais e agrícolas assim como através de descargas domésticas, causando distúrbios neste Ecossistema. Sendo assim, a avaliação da contaminação por metais é uma das prioridades tendo em conta que estes químicos têm comportamentos acumulativos e podem ser transportados ao longo de grandes distâncias. Nos estuários, os bivalves são componentes chaves das comunidades macrobentónicas devido o seu papel vital na comunidade e também por serem uma ótima fonte de alimentação para os seres Humanos. Na Lagoa de Óbidos, uma das espécies com estas características e intensamente apanhada é o berbigão Cerastoderma edule. Este berbigão foi descrito por vários autores como sendo tolerante a diversos poluentes. Sendo assim, no presente estudo, o principal objetivo foi utilizar C. edule como ferramenta de biomonitorização de contaminações por metais na Lagoa de Óbidos, avaliando a contaminação por Cádmio, Chumbo e Níquel durante as estações do ano de 2009 e 2010 em duas estações de amostragens (estação ML e BSB). Os resultados foram complementados com a análise de contaminações por metais em amostras de águas e sedimentos. Diversas respostas fisiológicas do berbigão foram também averiguadas de modo a perceber os efeitos da presença de metais e sua acumulação. Finalmente, avaliou-se a Dose Semanal Admissível Provisória (DSAP) para o consumo de berbigão para os mínimos e máximos de concentrações de metais detetados em cada estação de amostragem. Todos os metais foram detetados em amostras de água enquanto apenas o Pb foi detetado no sedimento. O Pb e o Ni foram detetados mais vezes na amostras biológicas do que o Cd. No entanto, as contaminações por metais Pb e Cd no berbigão foram frequentemente acima do limiar fixado pelas autoridades responsáveis enquanto o Ni se encontrou perto dos valores legislados. A avaliação da DSAP revelou a necessidade de aumentar a monitorização biológica neste berbigão visto que a dose semanal admissível foi muito baixa para os três metais. De um modo geral, C. edule refletiu as modificações ambientais, respondendo a modificações físico-químicas e contaminações por metais durante o período de estudo em ambas as estações de amostragem. Assim, este estudo permitiu concluir que Cerastoderma edule foi um bom e sensível indicador de contaminações por metais, especialmente para o Pb e preferencialmente para o Ni.

Melhoria de procedimentos internos no laboratório do Instituto dos Vinhos do Douro e do Porto, I.P.

Este relatório foi elaborado no âmbito do estágio curricular realizado na Direção de Serviços Técnicos e de Certificação do Instituto dos Vinhos do Douro e do Porto, I.P. Teve como principal objetivo apresentar propostas de alteração de procedimentos internos do laboratório do Instituto dos Vinhos do Douro e do Porto, I.P., no sentido de reduzir o tempo de resposta às solicitações, procurando uma melhor rentabilização tanto de equipamentos como de recursos humanos. Para atingir tal objetivo, foi elaborado o diagnóstico da situação, com base na informação recolhida na Direção de Serviços Técnicos e de Certificação, incluindo os dados fornecidos pelo software GLAB que dá apoio às operações realizadas no laboratório do Instituto dos Vinhos do Douro e do Porto. Além disso, foi efetuado o acompanhamento do circuito das amostras de produtos vínicos desde a sua receção, à análise nos setores do laboratório e posterior validação dos resultados. Dado que o estudo da entrada de amostras no setor Análise Mineral foi maioritariamente inconclusivo, apurou-se o custo por análise na determinação do chumbo e, ainda, foi realizada uma simulação determinar a despesa necessária para reduzir o número de amostras analisadas de cada vez que se liga o equipamento. Foi ainda comparado o custo da determinação do parâmetro furfural, análise que tanto pode ser realizada no setor Cromatografia Gasosa como no setor Cromatografia Líquida. Para isso, foram utlizados vários testes estatísticos. Com base na avaliação efetuada foram identificadas e propostas as seguintes oportunidades de melhoria: - Automação de uma das atividades realizadas no setor Físico-Química I, atividade esta necessária à preparação das análises; - Contrabalançar a sazonalidade verificada na receção de amostras dos clientes com as amostras provenientes da Direção de Serviços de Fiscalização e Controlo; - Inserção de algumas variáveis no software GLAB. É de realçar que a proposta referente à automação de uma das atividades realizadas no setor Físico-Química foi implementada pelo IVDP. Foram, também, identificadas propostas de futuras investigações.

Functional alkali tantalate 2D structures for microelectronics and related applications

Alkali tantalates and niobates, including K(Ta / Nb)O3, Li(Ta / Nb)O3 and Na(Ta / Nb)O3, are a very promising ferroic family of lead-free compounds with perovskite-like structures. Their versatile properties make them potentially interesting for current and future application in microelectronics, photocatalysis, energy and biomedics. Among them potassium tantalate, KTaO3 (KTO), has been raising interest as an alternative for the well-known strontium titanate, SrTiO3 (STO). KTO is a perovskite oxide with a quantum paraelectric behaviour when electrically stimulated and a highly polarizable lattice, giving opportunity to tailor its properties via external or internal stimuli. However problems related with the fabrication of either bulk or 2D nanostructures makes KTO not yet a viable alternative to STO. Within this context and to contribute scientifically to the leverage tantalate based compounds applications, the main goals of this thesis are: i) to produce and characterise thin films of alkali tantalates by chemical solution deposition on rigid Si based substrates, at reduced temperatures to be compatible with Si technology, ii) to fulfil scientific knowledge gaps in these relevant functional materials related to their energetics and ii) to exploit alternative applications for alkali tantalates, as photocatalysis. In what concerns the synthesis attention was given to the understanding of the phase formation in potassium tantalate synthesized via distinct routes, to control the crystallization of desired perovskite structure and to avoid low temperature pyrochlore or K-deficient phases. The phase formation process in alkali tantalates is far from being deeply analysed, as in the case of Pb-containing perovskites, therefore the work was initially focused on the process-phase relationship to identify the driving forces responsible to regulate the synthesis. Comparison of phase formation paths in conventional solid-state reaction and sol-gel method was conducted. The structural analyses revealed that intermediate pyrochlore K2Ta2O6 structure is not formed at any stage of the reaction using conventional solid-state reaction. On the other hand in the solution based processes, as alkoxide-based route, the crystallization of the perovskite occurs through the intermediate pyrochlore phase; at low temperatures pyrochlore is dominant and it is transformed to perovskite at >800 °C. The kinetic analysis carried out by using Johnson-MehlAvrami-Kolmogorow model and quantitative X-ray diffraction (XRD) demonstrated that in sol-gel derived powders the crystallization occurs in two stages: i) at early stage of the reaction dominated by primary nucleation, the mechanism is phase-boundary controlled, and ii) at the second stage the low value of Avrami exponent, n ~ 0.3, does not follow any reported category, thus not permitting an easy identification of the mechanism. Then, in collaboration with Prof. Alexandra Navrotsky group from the University of California at Davis (USA), thermodynamic studies were conducted, using high temperature oxide melt solution calorimetry. The enthalpies of formation of three structures: pyrochlore, perovskite and tetragonal tungsten bronze K6Ta10.8O30 (TTB) were calculated. The enthalpies of formation from corresponding oxides, ∆Hfox, for KTaO3, KTa2.2O6 and K6Ta10.8O30 are -203.63 ± 2.84 kJ/mol, - 358.02 ± 3.74 kJ/mol, and -1252.34 ± 10.10 kJ/mol, respectively, whereas from elements, ∆Hfel, for KTaO3, KTa2.2O6 and K6Ta10.8O30 are -1408.96 ± 3.73 kJ/mol, -2790.82 ± 6.06 kJ/mol, and -13393.04 ± 31.15 kJ/mol, respectively. The possible decomposition reactions of K-deficient KTa2.2O6 pyrochlore to KTaO3 perovskite and Ta2O5 (reaction 1) or to TTB K6Ta10.8O30 and Ta2O5 (reaction 2) were proposed, and the enthalpies were calculated to be 308.79 ± 4.41 kJ/mol and 895.79 ± 8.64 kJ/mol for reaction 1 and reaction 2, respectively. The reactions are strongly endothermic, indicating that these decompositions are energetically unfavourable, since it is unlikely that any entropy term could override such a large positive enthalpy. The energetic studies prove that pyrochlore is energetically more stable phase than perovskite at low temperature. Thus, the local order of the amorphous precipitates drives the crystallization into the most favourable structure that is the pyrochlore one with similar local organization; the distance between nearest neighbours in the amorphous or short-range ordered phase is very close to that in pyrochlore. Taking into account the stoichiometric deviation in KTO system, the selection of the most appropriate fabrication / deposition technique in thin films technology is a key issue, especially concerning complex ferroelectric oxides. Chemical solution deposition has been widely reported as a processing method to growth KTO thin films, but classical alkoxide route allows to crystallize perovskite phase at temperatures >800 °C, while the temperature endurance of platinized Si wafers is ~700 °C. Therefore, alternative diol-based routes, with distinct potassium carboxylate precursors, was developed aiming to stabilize the precursor solution, to avoid using toxic solvents and to decrease the crystallization temperature of the perovskite phase. Studies on powders revealed that in the case of KTOac (solution based on potassium acetate), a mixture of perovskite and pyrochlore phases is detected at temperature as low as 450 °C, and gradual transformation into monophasic perovskite structure occurs as temperature increases up to 750 °C, however the desired monophasic KTaO3 perovskite phase is not achieved. In the case of KTOacac (solution with potassium acetylacetonate), a broad peak is detected at temperatures <650 °C, characteristic of amorphous structures, while at higher temperatures diffraction lines from pyrochlore and perovskite phases are visible and a monophasic perovskite KTaO3 is formed at >700 °C. Infrared analysis indicated that the differences are due to a strong deformation of the carbonate-based structures upon heating. A series of thin films of alkali tantalates were spin-coated onto Si-based substrates using diol-based routes. Interestingly, monophasic perovskite KTaO3 films deposited using KTOacac solution were obtained at temperature as low as 650 °C; films were annealed in rapid thermal furnace in oxygen atmosphere for 5 min with heating rate 30 °C/sec. Other compositions of the tantalum based system as LiTaO3 (LTO) and NaTaO3 (NTO), were successfully derived as well, onto Si substrates at 650 °C as well. The ferroelectric character of LTO at room temperature was proved. Some of dielectric properties of KTO could not be measured in parallel capacitor configuration due to either substrate-film or filmelectrode interfaces. Thus, further studies have to be conducted to overcome this issue. Application-oriented studies have also been conducted; two case studies: i) photocatalytic activity of alkali tantalates and niobates for decomposition of pollutant, and ii) bioactivity of alkali tantalate ferroelectric films as functional coatings for bone regeneration. Much attention has been recently paid to develop new type of photocatalytic materials, and tantalum and niobium oxide based compositions have demonstrated to be active photocatalysts for water splitting due to high potential of the conduction bands. Thus, various powders of alkali tantalates and niobates families were tested as catalysts for methylene blue degradation. Results showed promising activities for some of the tested compounds, and KNbO3 is the most active among them, reaching over 50 % degradation of the dye after 7 h under UVA exposure. However further modifications of powders can improve the performance. In the context of bone regeneration, it is important to have platforms that with appropriate stimuli can support the attachment and direct the growth, proliferation and differentiation of the cells. In lieu of this here we exploited an alternative strategy for bone implants or repairs, based on charged mediating signals for bone regeneration. This strategy includes coating metallic 316L-type stainless steel (316L-SST) substrates with charged, functionalized via electrical charging or UV-light irradiation, ferroelectric LiTaO3 layers. It was demonstrated that the formation of surface calcium phosphates and protein adsorption is considerably enhanced for 316L-SST functionalized ferroelectric coatings. Our approach can be viewed as a set of guidelines for the development of platforms electrically functionalized that can stimulate tissue regeneration promoting direct integration of the implant in the host tissue by bone ingrowth and, hence contributing ultimately to reduce implant failure.

Aplicação foliar de molibdênio em adubos verdes e o desempenho do feijoeiro em sucessão

The knowledge of molybdenum application in legumes on the availability of N, by BNF, increased enzymatic activity and the residual effect caused on crops growth and yield can contribute to the greater scientific understanding involved in green manure processes. The aim of this study was to evaluate the Mo application and the N from Crotalaria juncea and Canavalia ensiformis green manures on common bean performance. Were conducted field experiments for the crops succession system (green manures - common bean) and laboratory essays for the enzymatic activities. Green manure production was installed in a factorial arrangement 2 x 4, with two green manure legumes species, sunnhemp (Crotalaria juncea) and jack beans (Canavalia ensiformis), and four Mo doses (0, 40, 80, 120 g ha-1) in the form of sodium molybdate (Na2MoO4), foliar applied, in a randomized block design with four replicates. For succession crop (common bean) additional treatment was added, beans grown without any fertilization, following the same experimental design from the previous crop. The dry matter decomposition and the N mineralization of green manure were monitored through collection of residues over time, by using the litter bags method. In laboratory were carried out tests of nitrate reductase activity in green manures and common beans at 90 and 66 days after sowing, respectively. The sunnhemp responded linearly positively to the application of Mo as the dry matter and N accumulation. While the jack beans presented a negative quadratic response for dry matter and there was no adjustment of regression models to N. The jack beans showed a higher decomposition rate and N mineralization compared to sunnhemp. The half lives for decomposing 50% of dry matter on the soil was 123 and 104 days to sunnhemp and jack beans, respectively, and 50% of N present in the residues was mineralized at 93 and 85 days. In common bean, differed from the control for number of pods the dose of 40 g ha-1 of Mo in both species of green manures and the dose 80 g ha-1 of Mo in jack beans. For number of grains only in sunnhemp on the dose of 40 g ha-1 of Mo differ from the control. The nitrate reductase activity was influenced by developmental stage of green manure species. In common bean, the activity of nitrate reductase was up to three times higher than the dose 0 g ha-1 of Mo compared to treatment with application of Mo in both species. There was no effect of Mo doses or species of green manure on common bean yield.

Lead (pb) toxicity in saccharomyces cerevisiae: the role of cell wall

O chumbo é utilizado em muitos produtos, tais como baterias, gasolina, tintas e corantes, resultando na sua libertação no meio ambiente. Neste trabalho, foi examinado o papel da parede celular da levedura Saccharomyces cerevisiae como uma barreira ou como alvo da toxicidade do chumbo. A biodisponibilidade do Pb é muito reduzida pelos componentes do meio de cultura YEPD, o que dificulta a avaliação da toxicidade deste elemento em concentrações ambientalmente realistas. Para avaliar a toxicidade de Pb em S. cerevisiae, em condições de crescimento, foram efetuadas diferentes diluições (10-100 vezes) do meio YEPD, as quais foram misturadas com várias concentrações de Pb (0,1-1,0 mmol/l). Observou-se que o YEPD diluído 25 vezes constituía a melhor condição de compromisso entre o crescimento celular e a precipitação de Pb. Os genes CWP1 e CWP2 codificam para duas grandes manoproteínas da parede celular da levedura S. cerevisiae; a deleção destes genes CWP aumenta a permeabilidade da parede celular. A suscetibilidade de células de levedura interrompidas no gene CWP1 (estirpe cwp1Δ) ou CWP2 (estirpe cwp2Δ) foi comparada com a da estirpe, isogénica, selvagem (WT). Verificou-se que o crescimento das estirpes cwp1Δ e cwp2Δ, no meio de cultura YEPD 25 vezes diluído, na presença de Pb, não diferiu do crescimento da estirpe WT. Este resultado sugere que a alteração da permeabilidade da parede celular não altera a sensibilidade de células de levedura ao Pb. Foi investigada o impacto do Pb na parede celular de levedura. Para este efeito, comparou-se a suscetibilidade ao dodecil sulfato de sódio (SDS), ao calcofluor (CFW) e a uma enzima que degrada a parede da célula (liticase), em células da estirpe WT não expostas ou expostas a Pb durante 4, 8 ou 24 h. Além disso, o conteúdo de quitina da parede celular de levedura foi investigada por coloração das células com CFW. Os resultados não mostraram uma alteração da suscetibilidade ao SDS e ao CFW, nas células tratadas com Pb; contudo, nas células tratadas durante 24 h com Pb, observou-se um aumento da sensibilidade à liticase e um aumento da coloração com CFW. Estes resultados sugerem que o chumbo interage com a parede celular da levedura e influencia a sua composição. Deve ser levado a cabo trabalho adicional a fim de confirmar estes resultados.

Síntese e caracterização de ligantes oximas e tiossemicarbazonas e seus complexos

Este trabalho apresenta a síntese e caracterização de cinco ligantes e quatro complexos derivados de oximas e tiossemicarbazonas. Entre essas, discutem-se as estruturas cristalinas/moleculares determinadas por difração de raios-X em monocristais: do ligante 4-feniltiossemicarbazida-isatina (Ligante 5), do complexo piridina-salicilaldeído-4- feniltiossemicarbazona de niquel (II) (Complexo 1), e do bis-4-feniltiossemicarbazonaisatina de chumbo(II) (Complexo 2). A estrutura do Ligante 5 cristaliza no sistema monoclínico, grupo espacial P21/c, com parâmetros de cela a = 6,3227(2) Å, b = 15,7973(7) Å, c = 14,4572(6) Å, β = 93,9330(10)°, V = 1440,61(10) Å3 , Z = 4. O refinamento da estrutura convergiu aos índices de discordância finais R1 = 0,0520, wR2 = 0,1471. Observa-se ainda a ocorrência de interações intermoleculares do tipo ligações de hidrogênio clássicas [N18−H3---O1′ 2,907(2)Å], com a formação de estruturas dímeras inter-relacionadas por simetria dentro da cela cristalina. Para a estrutura cristalina do Complexo 1, observa-se NC=4, e geometria de coordenação quadrada plana, onde o ligante saliciladeído-4-feniltiossemicarbazida comporta-se como quelante tridentado, e completando a esfera de coordenação do centro metálico temos uma molécula de piridina. A estrutura cristaliza no sistema monoclínico, grupo espacial P21/m, parâmetros de cela a = 12,8211(2) Å, b = 5,73370(10) Å, c = 23,9950(4) Å, β = 101,0910(10)°, V = 1730,98(5) Å3 , índices de discordância finais R1= 0,0320, wR2 = 0,0888, Z=3. O Complexo 1 apresenta ainda interações intermoleculares do tipo [N(3)-H(3)---S(1) = 3,5838(17)º, N(3)–H(3A)---S(1) = 160,91(19)º], formando estruturas dímeras e ligação de hidrogênio intramolecular não-clássica do tipo [C(10)-H(10)---N(2) = 2,838(2)º e C(10) – H(10)---N(2) = 122º]. A estrutura cristalina do complexo 2, apresenta duas formas independentes (uma com centro representado por Pb1 e outra por Pb2). Para a unidade com Pb1 temos o complexo composto por duas unidades do Ligante 5, que comportam-se como quelantes tridentados, e a esfera de coordenação é completada por interações intermoleculares do tipo η 2 areno π e através da ligação polarizada com o O1 da moléculas vizinha, o que confere ao íon Pb1 NC=9. A unidade Pb2 apresenta apenas as duas unidades do Ligante 5 coordenadas conferindo-lhe NC=6. A estrutura cristaliza no sistema monoclínico, grupo espacial C2/c, parâmetros de cela a = 37,9747(6) Å, b= 9,51280(10) Å, c = 31,4378(5) Å, β = 125,951(2)°, V= 9193,5(2) Å3 , Z = 4, índices de discordância finais= R1 = 0,0643, wR2 = 0,1227.

Megabalanus azoricus (Pilsbry, 1916) : building a scientific basis for its management

Tese de Doutoramento, Biologia (Ciências do Mar), 5 de Julho de 2013, Universidade dos Açores.

Massive open online courses (mooc) na formação contínua de professores: um estudo de caso

Os Massive Open Online Courses (MOOC) consistem em cursos online abertos e, normalmente gratuitos, que permitem a inscrição de um elevado número de participantes. A adesão a esta modalidade de educação, normalmente informal, foi o principal repto para propor uma oficina de formação, totalmente online. Com esta formação pretendeu-se fornecer as competências necessárias para que professores se sentissem capacitados para criar e distribuir os seus próprios MOOC. No presente trabalho recorre-se à metodologia de estudo de caso e procura-se inicialmente apresentar, através de pesquisa bibliográfica, a revisão de literatura relativamente aos MOOC. Posteriormente, com base nos dados obtidos pela observação participante e inquérito por questionário, evidenciam-se os principais resultados da oficina de formação online “MOOC: uma tecnologia educativa de futuro.

Efeitos da dieta hipoprotéica na formação e composição de estruturas dentárias: estudo experimental em ratos Wistar

Protein and caloric malnutrition has been considered one of the most concerned endemic diseases in Brazil and in the world. It has been known that depletion or reduction of proteins as far as meals are concerned can steer irreversible damages upon several organic systems. This study had as aim evaluate the effects the low-protein diet had over the formation and composition of the teeth components. 18 females and 6 males were used for the experiment. 12 from the 18 females had undertaken the low-protein diet (DH) for 03 weeks and the other 6, which remained, and those males had undertaken a controlled diet (DC) for the same period. All animals had the diets during their mating, pregnancy and lactation cycle. As soon as the offsprings had been born, 10 young males and females of each group faced a disease hood analysis to check the teeth germs of their lower fore teeth. The rest of the group had their lactation cycle normally 60 days. Then they were put to death and had their lower fore teeth removed both to be analyzed through a scanning electronic microscopy (SEM) of the structure alterations and to have their calcium checked by an atomic absorption of the phosphorus vanadate-molibdate method and by other minerals EDX method. The animals livers were removed to have their hepatic proteins analyzed as well. The histopatologic study showed that at first day of birth, all animals had their lower fore teeth come out. It was verified that 90% of the animals teeth were in an apposition and calcification period and it was possible to observe the dentin formation from 60% of the 90% already mentioned. Through the SEM method it could be realized that 90% of the animals of the DH group had their lower fore teeth easily broken and no definite shape. In this same group itself, it was also observed long micro fissures 369,66 nm ± 3,45 while the DC group had fissures of 174 nm ± 5,72. Now regarding the calcium and phosphorus concentration, it could be noticed that there was a great reduction of these components and other minerals in the DH group. Almost all minerals, except for the Cl and K, presented higher levels in the DC group enamel.The reduction of the protein input greatly influenced the offsprings´ weight and height. However the hepatic proteins had no important difference between the groups what can make one believe that those animals suffered from protein malnutrition of marasmic kind

Mapeamento de áreas de risco à saúde pública por meio de métodos geoestatísticos

Este trabalho tem por objetivo apresentar uma aplicação de métodos geoestatísticos na elaboração de mapas de risco à saúde pública, por meio da identificação de áreas com maior concentração de metais pesados. Foi escolhido o elemento chumbo (Pb), resultante do transporte aéreo ou do carregamento das partículas causado pela lixiviação do solo, em uma região com grande concentração urbana e industrial na Baixada Santista, São Paulo, Brasil. Elaboraram-se mapas das distribuições espaciais desse elemento por intermédio da krigagem ordinária; posteriormente, utilizando-se a krigagem indicativa, identificaram-se as áreas com valores de contaminação do solo superiores aos níveis máximos aceitáveis pelo órgão de controle ambiental do Estado de São Paulo, originando um mapeamento com áreas com maior probabilidade de risco à saúde pública. Os mapas resultantes mostraram-se ferramentas promissoras para auxiliar a tomada de decisão quanto a questões de políticas públicas relacionadas à saúde e ao planejamento ambiental.

Desenvolvimento de bloco de vedação com barita na composição de partida para blindagem de radiação X

This work main objective is to study the use of bricks in barium X-rays rooms in order to contribute to the optimization of shielding rooms diagnosis. The work was based on experimental measurements of X-ray attenuation (40 to 150 kV), using ceramic seal bearing the incorporation of barium sulfat (BaSO4). Different formulations were studied in three different firing temperatures and evaluated for incorporation in the ceramic body. The composition of 20% of barite processed at a temperature of 950 ° C showed better physical and mechanical properties, is considered the most suitable for the purpose of this work. Were produced bricks sealing composition formulated based on that presented the best technological features. These blocks were tested physically as a building material and wall protective barrier. Properties such as visual, deviation from the square, face flatness, water absorption and compressive strength were evaluated for all the blocks produced. The behavior of this material as attenuator for X-rays was investigated by experimental results which take into account mortar manufacturers barium through the different strains and compared with the reference material (Pb). The simulation results indicated that the ceramic block barium shows excellent properties of attenuation equivalence lead taking into account the energy used in diagnostic X-ray

La figura de Alcibíades en la historia de Atenas del siglo V y en la narrativa del banquete de Platón

A figura de Alcebíades atravessa a história de Atenas do século V e a narrativa do Banquete com sua força política dramática e sua representação de gênero desviante. O affaire Alcebíades assume assim um lugar central nas preocupações platônicas voltadas mais em geral para a revisão histórica dos anos-de-chumbo das stáseis, e mais especificamente com a ligação perigosa deste com Sócrates e o seu grupo. O sentido da incursão dramática de Alcebíades no Banquete, assim como de seu elogio a Sócrates, será lido à luz dos testemunhos de Xenofontes, Tucídides, Ândrocles e Andócides, entre outros, em busca da compreensão da lectio platônica da trajetória de uma das personagens mais marcantes da Atenas clássica. _______________________________________________________________________________ RESUMEN

Remoção de metais pesados em efluentes sintéticos utilizando vermiculita como adsorvente

Heavy metals are used in many industrial processestheirs discard can harm fel effects to the environment, becoming a serious problem. Many methods used for wastewater treatment have been reported in the literature, but many of them have high cost and low efficiency. The adsorption process has been used as effective for the metal remoal ions. This paper presents studies to evaluate the adsorption capacity of vermiculite as adsorbent for the heavy metals removal in a synthetic solution. The mineral vermiculite was characterized by differents techniques: specific surface area analysis by BET method, X-ray diffraction, raiosX fluorescence, spectroscopy in the infraredd region of, laser particle size analysis and specific gravity. The physical characteristics of the material presented was appropriate for the study of adsorption. The adsorption experiments weredriveal finite bath metod in synthetic solutions of copper, nickel, cadmium, lead and zinc. The results showed that the vermiculite has a high potential for adsorption, removing about 100% of ions and with removal capacity values about 85 ppm of metal in solution, 8.09 mg / g for cadmium, 8.39 mg/g for copper, 8.40 mg/g for lead, 8.26 mg/g for zinc and 8.38 mg/g of nickel. The experimental data fit in the Langmuir and Freundlich models. The kinetic datas showed a good correlation with the pseudo-second order model. It was conducteas a competition study among the metals using vermiculiti a adsorbent. Results showed that the presence of various metals in solution does not influence their removal at low concentrations, removing approximat wasely 100 % of all metals present in solutions

Estudo de inibidores de corrosão em concreto armado, visando a melhoria na sua durabilidade

This thesis has as objective presents a methodology to evaluate the behavior of the corrosion inhibitors sodium nitrite, sodium dichromate and sodium molybdate, as well as your mixture, the corrosion process for the built-in steel in the reinforced concrete, through different techniques electrochemical, as well as the mechanical properties of that concrete non conventional. The addition of the inhibitors was studied in the concrete in the proportions from 0.5 to 3.5 % regarding the cement mass, isolated or in the mixture, with concrete mixture proportions of 1.0:1.5:2.5 (cement, fine aggregate and coarse aggregate), superplasticizers 2.0 % and 0.40 water/cement ratio. In the modified concrete resistance rehearsals they were accomplished to the compression, consistence and the absorption of water, while to analyze the built-in steel in the concrete the rehearsals of polarization curves they were made. They were also execute, rehearsals of corrosion potential and polarization resistance with intention of diagnose the beginning of the corrosion of the armors inserted in body-of-proof submitted to an accelerated exhibition in immersion cycle and drying to the air. It was concluded, that among the studied inhibitors sodium nitrite , in the proportion of 2.0 % in relation to the mass of the cement, presented the best capacity of protection of the steel through all the studied techniques and that the methodology and the monitoring techniques used in this work, they were shown appropriate to evaluate the behavior and the efficiency of the inhibitors