Estudo da introdução de resíduo de britagem de rocha calcária e cinza de biomassa de cana-de-açúcar em formulações de argamassas colantes

The adhesive mortars are a mixture of cement, sand, and additives to polymers that retain the mixing water and promotes adherence, being used in setting on various ceramic substrates. The sand used in the production of these mortars is from the riverbeds, and with the increasing restriction of these sands extraction by environmental agencies, and often having to be transported over long distances to the consumer center. This work aims to design and physical and mechanical characterization of ecological adhesive mortar with total replacement of natural sand by sand from the crushing of limestone, and the addition of mineral ash biomass of cane sugar in partial replacement cement used in the production of adhesive mortar , aiming compositions that meet the regulatory specifications for use adhesive mortar. Standardized tests to determine the tensile bond strength (NBR 14081-4), determination of open time (NBR 14081-3) and determination of slip (NBR 14081-5) were performed. Were also conducted trials squeeze flow in different formulation, the mortar with addition of 15 % gray biomass of cane sugar for cement mortars as well as the total replacement of natural sand by sand limestone crushing, got the best performance among the mortars studied, it was found that the addition of biomass to replace cement is perfectly feasible due to its pozzolanic activity, which contributed to this reduction in the cement matrix formation of adhesive mortar

Desenvolvimento de uma unidade laboratorial para quantificação de BTX como poluentes atmosféricos, usando microextração em fase sólida

This dissertation aims the development of an experimental device to determine quantitatively the content of benzene, toluene and xylenes (BTX) in the atmosphere. BTX are extremely volatile solvents, and therefore play an important role in atmospheric chemistry, being precursors in the tropospheric ozone formation. In this work a BTX new standard gas was produced in nitrogen for stagnant systems. The aim of this dissertation is to develop a new method, simple and cheaper, to quantify and monitor BTX in air using solid phase microextraction/ gas chromatography/mass spectrometry (SPME/CG/MS). The features of the calibration method proposed are presented in this dissertation. SPME sampling was carried out under non-equilibrium conditions using a Carboxen/PDMS fiber exposed for 10 min standard gas mixtures. It is observed that the main parameters that affect the extraction process are sampling time and concentration. The results of the BTX multicomponent system studied have shown a linear and a nonlinear range. In the non-linear range, it is remarkable the effect of competition by selective adsorption with the following affinity order p-xylene > toluene > benzene. This behavior represents a limitation of the method, however being in accordance with the literature. Furthermore, this behavior does not prevent the application of the technique out of the non-linear region to quantify the BTX contents in the atmosphere.

Avaliação do efeito de gases poluentes na corrosão metálica: um experimento para o ensino da corrosão

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Novas formulações de fluidos de corte: otimização, propriedades e recuperação do óleo usado

Cutting fluids are lubricants used in metal-mechanical industries. Their complex composition varies according to the type of operation carried out, also depending on the metals under treatment or investigation. Due to the high amount of mineral oil produced in Northeastern Brazil, we have detected the need to better use this class of material. In this work, two novel formulations have been tested, both based on naphthenic mineral oil and additives, such as: an emulsifying agent (A), an anticorrosion agent (B), a biocide (C) and an antifoam agent (D). Each formulation was prepared by mixing the additives in the mineral oil at a 700-rpm stirring velocity for 10 min, at 25°C, employing a 24 factorial planning. The formulations were characterized by means of density, total acid number (TAN), viscosity, flash point and anticorrosion activity. In a subsequent study, oil-in-water emulsions were prepared from these novel formulations. The emulsions were analyzed in terms of stability, corrosion degree, percentage of foam formation, conductivity, accelerated stability and particle size. The samples were appropriately labeled, and, in special, two of them were selected for featuring emulsion properties which were closer to those of the standards chosen as references (commercial cutting oils). Investigations were undertaken on the ability of NaCl and CaCl2 to destabilize the emulsions, at concentrations of 2%, 5% and 10%, at an 800-rpm stirring velocity for 5 min and temperatures of 25º, 40º, 50º and 60ºC. The recovered oils were chemically altered by reincorporating the same additives used in the original formulations, followed by preparation of emulsions with the same concentrations as those of the initial ones. The purpose was to assess the possibility of reusing the recovered oil. The effluents generated during the emulsion destabilization step were characterized via turbidity index, contents of oil and grease, pH, and contents of anions and cations, observing compliance with the parameters established by the current environmental legislation (Brazil s CONAMA 357/05 resolution). It could be concluded that the formulations presented excellent physicochemical properties as compared to commercial cutting fluids, showing that the quality of the newly-prepared fluids is superior to that of the formulations available in the market, enabling technically and environmentally-safe applications

Poluentes atmosféricos: monóxido e dióxido de carbono no nordeste do Brasil

The interference of man in the middle atmosphere can be evidenced by the presence of carbon monoxide, gas associated with burning fossil fuels and carbon dioxide content, essential for respiration of plants and thermal balance of the Earth. In this thesis we initially evaluated the intensity of the spatial distribution of carbon monoxide in the Northeast of Brazil, and subsequently the behavior of temporal variations of the pollutants carbon monoxide and carbon dioxide in the atmospheric boundary layer Maxaranguape / RN. Research has shown that, driven by speculation and promoting the occupation of land for agriculture, cattle ranching and tourism in the Northeast of Brazil, the changes established by the man in the middle geomorphological affect the lower troposphere on a large scale, with a predominance of concentrations in central Pernambuco, Paraiba's south-central and central-west of Alagoas. However, the study of Maxaranguape / RN results showed little variation in carbon monoxide and carbon dioxide, with the speed of the wind persisting with values greater than 7.8 m / s, showing dispersion and diffusion of pollutants which resulted in faster renewal of local atmospheric air

Perfil espacial e temporal de poluentes nas águas da represa municipal de São José do Rio Preto, São Paulo, Brasil

In this manuscript, seasonal and spatial trends of water collected from two sampling places in the Preto River in the Turvo-Grande watershed were evaluated. Water samples were collected during June/07 to July/08 and parameters sulphate, total organic carbon, ammonia, conductivity, dissolved oxygen, temperature, dissolved total solids and nitrate were quantified. Seasonal trend indicated sanitary effluents as a point source of contamination in both sampling points. Vertical trends demonstrated that the Municipal Dam was not stratified and received a diffuse source of pollutants from flooding and agriculture runoffs. It was also verified that there is relatively fast ammonia consumption kinetics having a half-life time of 1.43 h which can explain the low ammonia concentrations found in these aquatic bodies.

Análise do comportamento de queima de argilas e formulações para revestimento cerâmico

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Determinação espectrofotométrica por injeção em fluxo de glifosato em formulações comerciais de herbicidas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Determinação espectrofotométrica de citrato de sildenafil em formulações farmacêuticas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desenvolvimento de um método reflectométrico ambientalmente mais amigável para a determinação de metoclopramida em formulações farmacêuticas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Segurança no trabalho de preparo de calda no tanque de 2.000l do turbopulverizador com formulações líquidas de agrotóxicos registradas para a cultura de goiaba

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Viabilidade da aplicação do método respirométrico de Bartha para determinação da biodegradação de poluentes ou resíduos em latossolos

Para avaliar a possibilidade de biorremediação em áreas contaminadas, é necessário determinar a biodegradação dos poluentes no solo. Para esta determinação, emprega-se comumente no Brasil, o método respirométrico de Bartha, adaptado de uma norma holandesa. Porém, os solos tropicais possuem características bem diferentes dos solos de regiões de clima temperado. Neste trabalho, foi estudada a aplicabilidade de tal método para um latossolo, tipo de solo predominante no Estado de São Paulo. A partir dos resultados obtidos, foi possível verificar que reações abióticas geram gás carbônico em quantidades significativas. Constatou-se, também, a dificuldade de esterilização do solo em autoclave, o que impossibilita a avaliação da remoção dos poluentes por outros mecanismos ou a biodegradação dos mesmos por microrganismos exógenos somente. Portanto, não se recomenda a aplicação do teste respirométrico de Bartha para a determinação da biodegradabilidade de poluentes em latossolos.

Estudo de metodologia analítica para a determinação do cetoconazol em formulações farmacêuticas

Ketoconazole is a synthetic broad-spectrum oral and topical antifungal drug derived from imidazole, effective in the treatment of superficial mycoses and systemic infections. In this study we have tested several methods to analyze ketoconazole in various pharmaceutical products containing this drug, employing techniques such as UV and IR spectrophotometry and thermal analysis. The results showed that UV spectrophotometry is a fast, practical and economical method and indicated that other methods, such as IR spectrophotometry and thermal analysis, could be good alternative methods for ketoconazole analysis in certain pharmaceutical forms.

Efeitos dos poluentes gerados pela queima de biomassa no transporte mucociliar nasal e percepção da qualidade de vida de cortadores de cana

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da associação de filtros solares sobre a estabilidade, liberação, permeação e retenção cutânea do p-metoxicinamato de octila em formulações fotoprotetoras

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)