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Equação mestra não-linear aplicada ao estudo de bioestabilidade óptica
(Universidade Federal de São Carlos, 2004-08-12) Yoshida, Alexandre Calzavara; Mizrahi, Salomon Sylvain; https://lattes.cnpq.br/8143137168199991
In this dissertation, we present a generalized master equation for a system of N two- level atoms pumped by a classical field, interacting with a reservoir. The kinds of reservoirs are assumed: (a) thermal, (b) squeezed vacuum. A master equation for the system was derived under Born and Markov approximations. The mean ¯eld approximation is done for the many-body system, so we obtain a non-linear master equation for a representative atom of the system . We discuss the optical bistable behavior of the output field, and analyze how much this phenomenon is sensitive to the number of atoms, the atom-reservoir coupling and to the parameters of de reservoir.
Gerenciamento de pneumáticos inservíveis: análise crítica de procedimentos operacionais e tecnologias para minimização, adotadas no território nacional
(Universidade Federal de São Carlos, 2004-08-12) Cimino, Marly Alvarez; Zanta, Viviana Maria; https://lattes.cnpq.br/0254925867760548
Lasting for 150 years of development and still playing the role of irretrievable, the tire, when turned into solid waste, becomes environmental concern. In Brazil, due to the considerable amount generated and the long-life of this solid waste, the disposal environmental risks reach large proportions, mainly in urban areas. For this reason, this is a subject which demands responsible management, along local governmental articulation, direct an indirect in charge subordinated by the rules of CONAMA nº 258 / 99 e 301 / 02, and ruled by Instrução Normativa nº 08/02, of IBAMA. As far as it may concern, this paper aims a critical investigation on operational procedures as well as on the technologies regarding tire solid waste management in the country, mainly under the legislation above-mentioned. The literature survey made possible the evaluation of procedures development on managing, by a diagnoses of present tire solid waste management in the country as much as its interfaces with environmental legislation. Also, it has supported the understanding of the level of involving and awareness of those in charge with the matter, and the present Technologies for minimizing the generated waste. This paper has been conceived to accomplish tire solid waste management regarding collecting strategies and good use in the ground of an interaction among the responsible segments. Its goal is the minimization of environmental impact and public health damage, which derive from improperly manipulation of solid waste in urban site, in order to appease future generations none of the problems that are faced nowadays.
Sistema de apoio à decisão: avaliação de cenários de gestão integrada de resíduos sólidos urbanos domiciliares
(Universidade Federal de São Carlos, 2004-08-12) Massukado, Luciana Miyoko; Zanta, Viviana Maria; https://lattes.cnpq.br/0254925867760548
The amount of waste generated by human activities associated with the decrease of appropriate final disposal sites have been presented as one of the great challenges to be faced by local administrations as well as by waste generating communities. Nowadays, household solid waste management is analyzed according to Descartes and Newton models, which are characterized by the separation and analysis of a system through its parts, resulting in isolated and narrow sighted decisions. Aspects such as the lack of technical training and financial resources contribute to this ongoing scenario. Considering the exposed problem this work aims to develop a decision support system to support the managers in the evaluation household solid waste management scenarios. The method consisted in defining and delimiting the work field of decision support system, followed by the construction of a conceptual model based on the acquired knowledge. The model was then translated in action screens and decision workflows, which were programmed in Delphi 6.0. The Extreme Programming (XP) methodology was applied, meaning that programmer and cognitive agent act together in the code of the system. Finally, the validation of the SIMGERE software in São Carlos (São Paulo State) was made in two moments - first on program s usability, in other words, if the system is friendly and easy understanding by user for treating of a new environment for him and; second on the coherence of the results obtained by the simulation of the municipal household solid waste management. For São Carlos case study, the landfill lifetime projection, nearly 2 years, was coherent with the expected. However, the economical simulation needs to be revised in order to better reflect the current management model.
Influência das condições de processamento na morfologia e das propriedades mecânicas de sistemas poliméricos moldados por injeção e sua predição através de redes neurais artificiais
(Universidade Federal de São Carlos, 2004-08-12) Lotti, Cybele; Bretas, Rosario Elida Suman; https://lattes.cnpq.br/2805349172281345
The influence of the injection molding parameters on the morphology and mechanical properties of poly(phenylene sulfide), PPS, and of a 80/20(%wt) blend of PPS/block copolymer styrene-ethylene-butylene-styrene ,SEBS, were evaluated. The injection molding conditions were defined through an experimental design. The lower and upper limits of each variable were set considering the material characteristics and the machine capacity. The software MOLDFLOW® was used to simulate the injection molding process, to define the cooling and holding times, to guarantee the part quality and to obtain the shear rate and bulk temperature profiles at the end of the filling step. For PPS, it was observed that the variables with highest influence on the gradient of crystallinity along the part thickness and on the mechanical properties were melt (Tinj) and mold (Tm) temperatures. For the PPS/SEBS blend, the flow rate (Q), mold temperature and holding pressure (Ph) were the variables with highest influence on the morphology. The aspect ratio of the SEBS particles, dispersed on the PPS matrix, was almost unaffected by the changes of the injection conditions; on the other hand, the mean particle size (caliper length along the major axis) and the value of the dispersion function represented qualitatively well the morphological variations observed for the blend. The artificial neural networks, built with experimental data and trained with the group cross validation method (GCV), predicted with good precision the morphology and the mechanical properties, starting from the injection molding processing conditions, as well as the mechanical properties starting from the morphological aspects.
Busca de substâncias bioativas em plantas amazônicas: Adiscanthus fusciflorus (Rutaceae), Trichilia pallida e T. rubra (Meliaceae)
(Universidade Federal de São Carlos, 2004-08-12) Rocha, Waldireny Caldas; Vieira, Paulo Cezar; https://lattes.cnpq.br/8923844563320377
The aim of this work was the search for antiparasitic and insecticide compounds in active extracts from the following amazon plants: A. fusciflorus (Rutaceae), T pallida e T. rubra (Meliaceae). The selected biological models were: 1) antiparasitic activity against the forms tripomastigota of T. cruzi, inhibition of the activity of gGAPDH of T. cruzi, inhibition of the activity of APRT of L. tarentolae and 2) insecticidal activity - against Spodoptera frugiperda and Atta sexdens a leafcutter ant. All the extracts were bioasseyed and liquid-liquid partition was carried out. From this each partition they were obtained five fractions that were obtained from each extract and these were assayed as well. The fractions were selected by two criteria: the) evaluation of the biological activity of the fractions in relation to your respective extracts and chemical profile of each fraction. Through successive fractioning it was possible to isolate and identify series of different compounds such as: dihydrocinnamic acid derivatives, coumarins, alkaloids, triterpenoids and steroids (some of them are described for the first time), limonoids and flavonoids. The identification of the compounds was carried out through different kind of NMR technique and comparison with data from the literature. The search for compounds with inhibitory activity on the enzyme APRT led to the furanoquinoline alkaloids. The results obtained for inhibitory effect of the enzyme gGAPDH of T. cruzi are promising compounds. Some of the isolated compounds showed interesting activity against trypomastigote forms of T. cruzi. The results obtained for inhibitory effect of the enzyme gGAPDH of T. cruzi are promising compounds. Some of the isolated compounds showed interesting activity against trypomastigote forms of T. cruzi. In the search for insecticidal compounds against S. frugiperda it was evaluated the activity of limonoids, cicloartane triterpenes, steroids, flavonoids, cumarins and alkaloids. Special attention was driven to the incorporation of skiamminine and the estimate DL50. In the bioassay carried out to A. sexdens it was observed the toxicity of some extracts, mainly the methanol extract of leaves from A. fusciflorus. It was also observed that some compounds exhibited antimicrobial activity on symbiotic fungi of A. sexdens and for some pathogenic bacteria. In conclusion, in this work it was possible to isolate and identify active compounds in all proposed biological models.