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Simulação estacionária e dinâmica do reator anaeróbio horizontal de leito fixo para o tratamento de águas residuárias
(Universidade Federal de São Carlos, 2005-03-23) Fabiano, Maressa; Kwong, Wu Hong
This work studied the horizontal-flow anaerobic immobilized biomass (HAIB) for the treatment of wastewater, developed in the Department of Hydraulics and Sanitation of the School of Engineering of São Carlos - USP. For the simulation and modeling of RAHLF, data of two HAIB were used, and; when the regime is the dynamic, one in bench scale treating wastewater containing poisonous substances (BTEX) and when the regime is the stationary, other in pilot scale treating sewer sanitarium. The study was divided in two parts: stationary regime and transient regime. In the first case the models were analyzed: pseudo - homogeneous with and without axial dispersion and the heterogeneous with axial dispersion; in the second case, the models were analyzed: pseudo - homogeneous and heterogeneous. The models of the first case were resolved respectively for the numeric methods of Runge - Kutta, of the finite differences and of the orthogonal collocation. In those models, when if it despised the axial dispersion the kinetic constant of first order was adjusted. Already in the other two models acted in this same case, they were adjusted the kinetic constant of first order and the coefficient of axial dispersion simultaneously. All of the methods numeric employees in the first case described the tendency of variation of the concentration well along the reactor and inside the particle, making possible the convergence of the solutions. The models without axial dispersion foresaw concentration values in the exit closest of the experimental values than the models with dispersion, and this, for his/her time foresaw closer values to the experimental ones in the intermediate points. In the second case, the models were solved through two methods, the method of the finite differences and the method of the sequence. The methods got to solve the equations that describe the behavior of the reactor satisfactorily and they show that the answer of the exit in the reactor is appropriately made calculations.
Cálculo de lajes lisas com protensão parcial e limitada
(Universidade Federal de São Carlos, 2005-03-23) Mello, Ana Lucia Vargas de; Carvalho, Roberto Chust; https://lattes.cnpq.br/3633394168236221
Flat slabs are associated with rationalization, better esthetic conditions and higher speed during construction. The use of post-tension can make this system viable since it strongly improves the structural performance in respect to punching and in case of extreme deflection of the slab. The durability of prestressed concrete elements is assured by meeting their limiting crack requirements. The Brazilian code for structural concrete prescribes the obligation of using limited post-tension, within aggressive environments, and in other cases, partial posttension. The verifications to be made in both cases are different, as well as the calculation procedures. In this particular research, some procedures to determine the number of tendons that are needed for partial and limited post-tension are presented, as well as the wide range of possibilities in the use of quantitative passive and active reinforcements. Possible tendon profiles, horizontal tendon layouts, and the use of bonded or unbonded tendon are also suggested and discussed. All procedures are shown within a numerical example and according to the conditions foreseen in the Brazilian code for structural concrete. Based on the found results, the adopted procedures provided good solutions for design of post-tensioned slabs.
Identificação das fontes de poluição atmosférica na cidade de São Carlos-SP
(Universidade Federal de São Carlos, 2005-03-23) Pozza, Simone Andréa; Coury, José Renato; https://lattes.cnpq.br/5530984461673946
The quality of the atmospheric air is of great importance for the health of the population. Among the quantifiable aspects of the air quality, one can find the particulate matter (PM) concentration in the atmosphere, whose fine (PM10) and ultra-fine (PM2.5) fractions have been extensively studied, as these particle size fractions are particularly damaging for the human health. The main objective of this work was the identification of emission sources of breathable particulate matter, as well as the quantification of their relative participation in the formation of the air pollution in São Carlos/SP, with the use of the reception model. The experiments used the dichotomous sampler for the collection of the particulate matter. Samples were taken in the receptor site, at the city center, in one year period. Also, the emission profiles of local sources (soil, vehicular emission, road dust re-suspension, sugar cane burning and vegetable burning) were measured. The mass concentration was obtained by weighing the sample filters before and after collection. The filter were then submitted to XRF analysis, and 14 chemical elements were quantified (Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Cu, Zn, Pb). Moreover, carbon detection was carried out by the DIC (dissolved inorganic carbon) and DOC (dissolved organic carbon) techniques. These values were fed to the EPA s CMB8 computer pack that calculates the relative contributions of the sources in the reception site. The results show the seasonal dependence of the sources in São Carlos, with the important presence of the vehicular emissions in the whole year. For the fine fraction, the contribution of the sugar cane burning was significant, in the dry season. In the ultra-fine fraction, an appreciable amount of secondary sulfur was found. The comparison between the source contributions calculated from the results of these work with those calculated utilizing data from the EPA´s SPECIATE library revealed very different profiles, confirming the importance of utilizing local sources in the modeling.
Influência de íons metálicos na estrutura de substâncias húmicas detectados por espectroscopia
(Universidade Federal de São Carlos, 2005-03-23) Barriquello, Marcilene Ferrari; Neves, Eduardo Fausto de Almeida; https://lattes.cnpq.br/5299097658671260
INFLUENCE OF METAL CATIONS IN THE STRUCTURE OF HUMIC SUBSTANCES AS DETECTED BY SPECTROSCOPY, involves a study by which starting from precursors of humic substances, some polymers were obtained, characterized and comparable with samples of humic acids. One such polymer with similar characteristics with humic acids was obtained by using as precursors hydroquinone, p-benzoquinone and 4-aminbenzoic acid, subjected to a synthesis under polymeric oxidation at an alkaline medium. The following structural characteristics of such polymers were studied in comparison with humic acids: influence of Cu, Fe and Mn cations in the structure of the synthesized polymers by spectral characteristica of Fourier Transform Infrared Spectroscopic (FTIR), absorbance with UV-Vis light, fluorescence; experiments with Size Exclusion Chromatography (SEC) and Atomic Force Microscopy (AFM) with the polymers and humic acids. It has been found that the complexation with the Cu, Fe and Mn cations has affected the structure by increasing the molecular size as observed by the Size Exclusion Chromatography. After complexation with the metal cations the FTIR, UV-Vis and Fluorescence spectra has shown significant changes due to structural modifications, which indicates complex formation specially with the carboxylic and phenol groups found in the obtained polymers.
Uma contribuição para a formulação de diretrizes para elaboração do manual do usuário de edifícios
(Universidade Federal de São Carlos, 2005-03-23) Aguilera, Camila Garcia; Novaes, Celso Carlos; https://lattes.cnpq.br/7340467051481570
Analyzing the existent norms, this investigation pretends to offer subsidies to collect and elaborate the information that must be include into the building user guide. In this manner, the user could accomplish correctly his functions. The focus of the research refrains from the user guide, whose objective is to transmit to the landed property s owner, in the instant of the key s delivery, the basics notions to the corrected use and maintenance of his propriety, assuring the durability, preventing damages from a bad use or the lack of conservation, and giving him a higher security and economy. For this valuation, the country s rules and legislation was analyzed, because now it claims the adoption of the manual, and norms and social behavior from other countries too, resulting in a consumer s defense movement. The work talks about constructive projects and processes used in the building sub sector and how the application of concepts and softwares can improve the satisfaction and the client s attending. The research presents too technical features like the retro alimentation and the as built project. The case study realized into this job, which consists in an interview accomplished with 11 engineers and 150 guide s users, reveals that, in spite of the consensus about the uses of the user guide, it further doesn t offers satisfactory and suitable information for it purposes. Rely on this data, the present work analyzes, comments and suggests modifications to the existents norms of the guide s elaboration serving.