Browsing by Issue Date, starting with "2008-07-10"

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Fração de filme líquido nas paredes de um lavador Venturi
(Universidade Federal de São Carlos, 2008-07-10)
Daher, Maristela de Almeida Felício
;
Coury, José Renato
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https://lattes.cnpq.br/4502024143494992
The study of the liquid film in the walls of a Venturi scrubber was chosen as the target of this work for representing one of the important phenomena that influence the collection efficiency of the equipment. Such efficiency decreases with the presence of the film once it has a superficial area per volume much smaller than the drops and, consequently, contributes very little in the removal of particles. Furthermore, the pressure drop on the Venturi depends on the energy spent to accelerate the drops and also of the attrition between the gas and the surface of the film. These two important parameters depend on the liquid fraction in the form of film. For these reasons, it is important for the project of Venturi scrubbers the quantification of the film fraction. The present work, therefore, carried out an experimental investigation of the effects that the liquid injection through multiple jets exerted in the formation of the liquid film in a Venturi scrubber of rectangular cross section. The behavior of the fraction of liquid film in each wall separately and of the total fraction of liquid film extracted were analyzed, varying the liquid flow rate from 0,3 to 1,2 l/min for gas velocities of 59, 64, 69 and 74 m/s. Throat lengths of 100, 160 and 220 mm were utilized. The results showed that the film fraction varies with the gas velocity, with the configuration of the liquid injection, with the liquid flow rate and with the axial distances along the throat. The analysis of the film extraction in the individual walls follows an asymmetric behavior in all operational conditions, showing a larger film deposition in the inferior wall independently of the injection configuration, thus indicating the effect of the gravity in the film deposition. Hence, the total fraction of liquid extracted from the four walls of the scrubber made possible a more satisfactory interpretation of the results. Within the experimental range investigated, the injection through four orifices at the gas velocity of 74 m/s at the higher liquid flow rates presented the smaller deposition of liquid in the scrubber walls. It was also evident that the deposition is dependent on the penetration of the jet: low penetrations tend to deposit in the jet injection wall while high penetrations deposit in the opposite wall. There is, therefore, a point of minimum deposition for the intermediate penetration of the jet. The best operational conditions, i.e. the smallest film fraction deposited in the walls, was obtained for the largest gas velocity and for the liquid being injected simultaneously through the four walls.
Inteligência computacional aplicada à automação de biorreator para produção de Penicilina G Acilase (PGA)
(Universidade Federal de São Carlos, 2008-07-11)
Fernandes, Pedro Luiz
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Giordano, Roberto de Campos
;
https://lattes.cnpq.br/0834668419587001
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https://lattes.cnpq.br/6037526193877152
Biotechnology has presented, in the last years, a rapidly growing development. New biotechnological industrial processes are constantly introduced using different microorganisms and/or enzymes. In this context, the application of process control and optimization techniques has become a need for biotechnological based industry. A technological approach was developed in this dissertation to bioreactor monitoring and control operating in fed-batch model to produce the penicillin enzyme G acilase (PGA) by means of wild cepa of the microorganism Bacillus megaterium. This enzyme is of great industrial importance, being used in the manufacture of semi-synthetic β-lactamic antibiotics. This case study presents the main difficulties faced in the control of biological processes in general: the variability of kinetic parameters and the limited availability of on-line information. In order overcome these difficulties, a unconventional architecture was proposed for a dynamic and adaptive controller using filters, some of them developed in this work, and applying Computational Intelligence (CI) methodologies both in direct and hybrid form. The inference for the microbial concentration (Cx) state variable, a very relevant objective for the logic of the controller, was performed by a softsensor that had as input the filtered values of the sensors signals of the molar fractions of CO2 (yco2) and O2 (yo2) in the effluent gases, of the air feeding flow and of agitation velocity. The respiratory quotient (RQ), calculated from these data, was also used by the algorithms of the software developed here. For the Cx inference, the softsensor employed a hybrid intelligent system (HIS) composed by a neural networks ensemble (RNE) and a fuzzy rule based system (FRBS). These techniques were structured to complement each other such that the RNE infers the microbial concentration (Cx) capturing real-time process data (empirical knowledge) and the FRBS corrects this inferred value using phenomenological based knowledge. The obtained results demonstrated a more robust inference by using this architecture, even supporting some degree of extrapolation. Another important operational parameter is the definition of the initial and final instants of feeding flow of supplemental. In order to meet this goal, a logic was employed that is able to accurately predict this moments, using the CO2 (yco2) molar fraction signal, filters and adaptive fuzzy sets.
A geratividade do comportamento verbal : divergências entre as propostas de B. F. Skinner e N. Chomsky
(Universidade Federal de São Carlos, 2008-07-14)
Bandini, Carmen Silvia Motta
;
Rose, Julio Cesar Coelho de
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https://lattes.cnpq.br/3386857761295187
One of the most interesting questions in the study of the language is its original character. Any philosophy or science that tries to explain language must account for this peculiar characteristic. Radical Behaviorism of B. F. Skinner and the theory of Generative-Transformational Grammar of N. Chomsky were very important sources of explanation of language phenomena during the 20th Century. Chomsky was one of the most famous critics of Skinnerian behaviorism. His review of Skinner s Verbal Behavior was probably more known around the world than Skinner s original book. In this review, Chomsky asserts that the operant model can not explain the original character of language. However, recent works have shown that Skinner tries to consider this characteristic when he talks about language. Within this context, the present dissertation intended to investigate Skinner s treatment of the creative processes of verbal behavior, set against Chomsky's theory. This work also tried to search the conceptual categories used by Chomsky to criticize Skinner and use this conceptual categories to improve the analysis of Skinner s text. In addition, this dissertation also attempted an internal analysis of Skinnerian concepts involved in the explanation of verbal behavior, as well as an assessment of the truth or falseness of Chomsky s critical work. We found three conceptual categories used by Chomsky in his Review of Skinner s Verbal Behavior. The survey of such categories allowed a fruitful analysis of Skinnerian account of the generative character of verbal behavior. It is argued that Chomsky committed many conceptual mistakes in his Review and because of these mistakes his work cannot prove that Skinnerian analysis of verbal generativity is impracticable. It is also argued that Skinnerian theory about verbal (and not verbal) generativity does not seem to be in any contradiction to the philosophy of science that Skinner adopts. We then conclude that, from the theoretical standpoint, the behaviorist explanation of verbal behavior and its generativity can configure an useful model.
Desenvolvimento de um fotômetro portátil usando LED como fotodetector e de procedimentos analíticos automáticos empregando multicomutação em fluxo
(Universidade Federal de São Carlos, 2008-07-16)
Silva, Milton Batista da
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Reis, Boaventura Freire dos
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https://lattes.cnpq.br/7619359855870896
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https://lattes.cnpq.br/4056099092803481
This work involves the development of portable photometer using a LED (Light Emitting Diode) as source of electromagnetic radiation and another one LED as photodetector. The viability of this proposal was demonstrated in an automatic photometric titration procedure, which was implemented based on the binary search process. The sensitivity improvement of the classic analytical methods to improve limit of detention is a current demand of the analytical chemistry, to attain the maximum limits established by the regulatory agencies. In photometric detention a resource to attain this requirement would be the increasing of the optical path of the flow cell. In flow analysis, the geometry of the usual cells flow does not allow the increase of the pathlength. The availability in the market of LED with emission beam high intensity within narrow angle of scattering, allows its use to develop homemade photometer. In this work, a LED with this characteristic was used to allowed the use a flow cell with optical path of 200 mm. The flow cell was designed with geometry appropriate to allow the direct coupling of radiation source (LED) and photodetector. According to CONAMA (National Advice of the Environment), orthophosphate is the chemical species that the maximum concentration allowed in fresh water is in the order of g L-1 level. The use of flow cell with optical path of 200 mm was evaluated in an automatic procedure for determination of orthophosphate in waters. The procedure was implemented using the multicommutation flow injection analysis process, using the photometric method based on the reaction with ammonium molybdate and reduction with stannous chloride. Different photodetectors have been employed in prototypes of photometers, thus aiming to compare the performance of the usually employed photodetectors, a set of experiments was carried out, submitting the photodetectors to the same work conditions. The photometric determination of orthophosphate in waters was selected as model to test the response of the used photodetectors.
Atividade inseticida de espécies de trichilia frente à lagarta-do-cartucho do milho spodoptera frugiperda
(Universidade Federal de São Carlos, 2008-07-18)
Nebo, Liliane
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Vieira, Paulo Cezar
;
https://lattes.cnpq.br/8923844563320377
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https://lattes.cnpq.br/6724147949765463
This work presents the phytochemical study and biological assays carried out with organic extracts of fruits and seeds from Trichilia claussenii, T. elegans and inflorescence from T. catigua against S. frugiperda. Among the extracts assayed, the methanol extracts of seeds from T. claussenii and inflorescence from T. catigua presented the highest insecticidal activity, with 64,0 and 64,4 % of mortality, respectively. The bioassay-guided study of the methanol extract of seeds from T. claussenii led to identification of ��-phenylalkyl and alkenyl fatty acids, active substances in this extract. The flavonoid ent-catequin was isolated from the methanol extract of inflorescence from T. catigua and it was associated with the insecticidal activity found in this extract. Fatty acids with the methylene chains ranging from C-5 to C-16 were assayed against S. frugiperda. Tests showed that the hexanoic, nonanoic and decanoic acids, displayed the highest rate of mortality at concentration of 10,0 mg/mL. The study of the three species allowed isolating and identifying the following compounds: a mixture of ��-phenylalkyl and alkenyl fatty acids, ��-lactonas, 4-hydroxy-N-methylproline, N-methylproline, uridine, uracile, entcatequin, 5-O-cafeoylquinic acid and the steroids 3-��-O-��-Dglucopyranosilsitosterol, ��-sitosterol, campesterol, estigmasterol e sitostenone. The limonoids 11��-acetoxyobacunone and 1,2-dihiyro-1��-acetoxy-11��-acetoxy-14,15-epoxycneorin R were isolated for the first time from a Trichilia species.
Modificação superficial de óxidos : proposta de um modelo simples e sua aplicação em sistema aluminazircônia
(Universidade Federal de São Carlos, 2008-07-18)
Dalmaschio, Cleocir José
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Leite, Edson Roberto
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https://lattes.cnpq.br/1025598529469393
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https://lattes.cnpq.br/5209978120430790
In this study a model that makes possible to foresee the limit of modifier oxide of surface that results in the complete support coating with a unit cells monolayer was proposed. From such limit, the lattice of the modifying material should be formed. According to the proposal, the identification of the crystalline phase of the modifier for coating levels lower than the delimited can be an indication that the deposition method adopted does not result in high dispersion. The model s applicability was demonstrated in aluminas coating with zirconium oxide by using a resin obtained through the polymeric precursors method for dispersion of modifier. The characterization results for X-ray diffraction (DRX) presented excellent correlation with the diagram built from the model. Concentrations maps obtained by energy dispersive x-ray spectroscopy (EDS) evidenced that the modifier deposition occurs on the support. Through high resolution transmission electron microscopy (HRTEM) analysis a monophase material (alumina) without indication of amorphous phase was observed below the saturation limit. Above the limit, two different lattice parameters were observed in the images, being one associated to the alumina and other to the tetragonal zirconium oxide. X-ray photoelectron spectroscopy (XPS) analyses proved that the increase in the zirconium oxide concentration is accompanied by enrichment of the surface by the modifier due to the coating formation. With this technique a strong support-coating interaction, with formation of Al-O-Zr bonds, was also detected. X-ray absorption spectroscopy (XAS) analyses reinforced the argument that the lattice was formed for concentrations above the saturation limit proposed in the model. A better dispersion was evidenced using multiple steps for dispersion of the modifier. Zeta potential measurements indicated attractive interactions more intense between support and resin than between modifier and resin, which explain the better dispersion possible when multiple steps were used.
O que é, o que é?: um ambiente de co-autoria de jogos educacionais baseados em cartas contextualizadas usando conhecimento de senso comum
(Universidade Federal de São Carlos, 2008-07-21)
Pereira, Eliane Nascimento
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Silva, Junia Coutinho Anacleto
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https://lattes.cnpq.br/6200743168568684
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https://lattes.cnpq.br/1779566969221196
Computer use as a mediating tool in education has been discussed and researched in different areas. The aims are to promote knowledge building, to motivate and to engage students and teachers in it. It also increases their digital literacy. However, several factors should be considered in implementing computers at school, for instance, how to involve teachers so they accept computer to change how they teach. Teachers training program should aim at helping them to include computer in their class activities and also to help them to choose software suitable to pedagogic aims defined in school syllabus. This research fulfills the latter aim concerning developing and evaluating an online system which allows teachers to be co-author of an educational online game. Teachers can contextualize it to students' reality, exploring the transversal themes proposed in the Parameters National Syllabus Standards for primary education, allowing teachers to create, even if partially, a computer tool to promote significant learning or to reinforce concepts presented in class. The content card is an outcome of the use of a filtering process of a semantic net generated from the knowledge base of common sense of the Open Mind Common Sense Brasil (OMCS-Br) project. To accomplish the research aims, a step-by-step guide was developed to help teachers to elaborate of the game content. This online game is a guessing game based on contextualized cards, which request players to discover which is secret word from a specific given topic, using some clues presented to him. This game system was developed according to international usability parameters. Then an evaluation test was conducted to evaluate users' satisfaction (in this case specific teachers and students) when they interacted with the game system. In general it can be considered objectives were fulfilled. First, a game system was developed integrated knowledge base. Second, evaluation test reported teachers satisfaction in being co-author a computer game for their students and students are looking forward to using this computer game as support to pedagogic activities at school.
Estudo da fusão de superfície da prata por dinâmica molecular
(Universidade Federal de São Carlos, 2008-07-23)
Gonçalves, Luis Gustavo Vieira
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Rino, José Pedro
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https://lattes.cnpq.br/6801067322823031
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https://lattes.cnpq.br/6801297606724628
A study about surface melting on silver using equilibrium molecular dynamics simulation is the proposal of this work. We applied the Embedded Atom Method as the many-body interaction potential to describe Ag properties. Simulations were done in the microcanonical ensemble, for the study of bulk properties, and in the canonical ensemble, for simulations of the solid with surfaces. As a preliminary result, we obtained the equilibrium melting point Tm equal 1264(12)K from solid-liquid coexistence configurations. Surfaces were simulated using repeated slabs separated by vacuum in the z direction, while keeping periodic boundary conditions in the remaining directions. Results showed that Ag[110] is the lone orientation that has surface melting. Ag[111] maintains its crystalline structure even after reaching Tm, while it could be overheated by 100K. Other properties like density of states, thermal expansion and surface relaxation were in good agreement with experimental data.
Caracterização genética e biométrica das populações de camarão rosa Farfantepenaeus brasiliensis de três localidades da costa do Rio Grande do Norte
(Universidade Federal de São Carlos, 2008-07-25)
Pinheiro, Allysson Pontes
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Galetti Júnior, Pedro Manoel
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https://lattes.cnpq.br/7398754661670478
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https://lattes.cnpq.br/6694712411033380
Shrimp catch is one of the main fishing activities in the world, mostly for the high value of commercialization reached by shrimp meat. Biological characteristics of penaeids make this group of shrimps aspirant to show different levels of population structure. Penaeid species like Farfantepenaeus brasiliensis are dependent of the estuary to complete its life cycle. Thus, the aim of this work was to evaluate if populations of F. brasiliensis, from the coast of Rio Grande do Norte, are structured by morphometrical and molecular analysis. Several measurements (Lt, Lc, La and weight) were recorded for each specimen. Divergence between places has been evaluated by univariate (ANOVA) and multivaried (Discriminant Analysis) techniques. FSTAT and GENEPOP were used to get the molecular levels of genetic variability in each population, as well as, comparisons between populations. The frequentist and bayesian methods were used to detect migrants in GENECLASS software. The results of the 3 morphometric analysis pointed out differences between sex-ratio in all analyzed localities. These results probably are related with differences in growth rate between sex and/or spatial stratification. Significant morphometric differences were obtained between populations by the univariate and multivaried methods. These differences could be consequence of the estuary necessity to complete the life cycle in F. brasiliensis. Likewise, local differences could contribute for these results. Females were more divergent among different areas than males. This result also could be a reflex of the biological characteristics of this species, due to the great relation between the spawning places and the females. The interval between insemination and spawning in shrimp females can be of 10 to 20 days. The molecular results showed medium levels of genetic variability in the analyzed localities. When compared with other species from the same family Ho varied between 0,471 and 0,540. The FST values did not showed genetic structure. However, these results could reflect the low number of analyzed loci, or the predominance of females in the samples, a characteristic inherent of the penaeids. The procedure used to detect migrants did not support the existence of migrants among evaluated populations; however some individuals had been excluded from all populations, probably belonging to other populations not sampled. In such a way, the set of results obtained, plus the biological characteristics of this species, and the distinct environmental characteristics among areas allow us to infer an existence of at least two F. brasiliensis stocks in Rio Grande do Norte coast.
Histórias infantis e matemática: a mobilização de recursos, a apropriação de conhecimentos e a receptividade de alunos de 4ª série do ensino fundamental
(Universidade Federal de São Carlos, 2008-07-28)
Souza, Ana Paula Gestoso de
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Oliveira, Rosa Maria Moraes Anunciato de
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https://lattes.cnpq.br/3064136997342775
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https://lattes.cnpq.br/2662760426985944
Considering a teaching/learning environment where literature and mathematics were connected, this research tried to investigate the ways by which the students of a fourth grade elementary school class acquired the school content, managed it and accepted the proposed methodology. In the theoretical reference, we discuss concepts and ideas such as: the perspectives of some authors on knowledge fragmentation and how it takes place in school; the means by which knowledge can be addressed in school; and the relationship of the students with such knowledge and with the teaching/learning context in which they are placed. We also discuss the impregnation of language with mathematics, the potential of reading, and the possibilities of developing a methodology that connects education, language, literature and mathematics. This research was developed in a fourth grade class of a public school in São Carlos (São Paulo State) according to a pedagogical sequence that articulated mathematics and children s literature the books chosen were The duck s lollipop and Sweet Fractions . The mathematical content developed was: fraction concept of part-whole, comparison and equivalence of fractions. The classes were recorded on video. Other information includes the number of students 33 and the fact that all of them participated in the pedagogical intervention, although only 13 had their learning processes and exercises analysed: the ones who had authorized us to do so. During the development of the pedagogical intervention, we could notice that many students were receptive to the work proposed i.e., the connection between literature and mathematics and acted as active subjects, taking part in the activities. Another aspect to point out is the importance of the use of manipulative materials for the students learning, because they allowed the children to come up with their own thoughts, and to produce and test hypotheses and strategies, getting involved in the process of understanding the material presented. By investigating the learning process of these students, we emphasize the educator s role as a mediator who, being aware of the previous knowledge of the students about certain subjects and understanding the strategies used by them to solve a situation, will be able to use some conditions and effective interventions in order to enable the students reasoning. Therefore, the students developed assumptions, strategies and interacted with the narratives, constructed mathematical notions, established a relationship of interiority with the knowledge, and the process itself involved the personal knowledge, life stories and experiences, i.e, the uniquenesses of each human subject who is part of the educational process and who creates himself/herself in daily school life, also creating the whole environment.
Avaliação química de solos tratados com vinhaça e cultivados com alfafa
(Universidade Federal de São Carlos, 2008-07-29)
Bianchi, Silmara Rossana
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Nogueira, Ana Rita de Araújo
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https://lattes.cnpq.br/7034773971317045
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https://lattes.cnpq.br/8503338877948315
It is fundamental the presence of nutrients in the soil to assure its good quality and performance. If the soil is not able to supply the adequate levels of nutrients that the plants need to survive, these nutrients have to be added in the form of salts or organic fertilizers. Vinasse, the main residue produced during alcoholic distillation (13 liters of vinasse to 1 liter of produced alcohol), is mainly constituted of organic matter, elevate amount of nitrate and potassium, and it has been used as a substitute of mineral fertilizers. In this work, the use of sensors that select chemical such as nitrate, ammonium, potassium and phosphate and its associated instrumentation was evaluated in the soil s ions monitoring throughout growing doses of vinasse in an alfalfa culture by using in situ analyses. The vinasse additions effects in the soil s chemical characteristics, in the alfalfa production, and in the ions leaching were evaluated. The use of vinasse to replacement mineral fertilizer in the alfalfa production was also evaluated. During the experiments, performed in a greenhouse, vinasse doses corresponding to 0, 300, 400, 600, and 750 m3 ha-1 were applied in the clay soil (Orthic Ferralsol), and 0, 150, 300, 450, and 600 m3 ha-1 were applied in the sandy soil (Ustoxix Quatzipamment). Doses of 150 mg kg-1 of K as KCl and K2SO4 were provided as mineral fertilizers. The results indicated the viability of the use of sensors installed in the probe in the ions soil monitoring, except of ammonium, which sensor suffers interference of the high amount of potassium present in the vinasse. Multiparametric analysis of the results allowed the view of the qualitative effects of the different treatments. Soils treated with vinasse presented an increase in the potassium, calcium, and magnesium amount, in the exchanged cations capacity, in the bases saturation and in the pH. The foliar amount of potassium harvest in the two kinds of soils also increased, and the vinasse fertilization produced more dry matter when compared with the mineral KCl and K2SO4 treatments. The amount of nitrate and ammonium presented in the leached solution were higher than the allowed by the Conama 357.
Estudo da interação de elétrons com moléculas relevantes à atmosfera
(Universidade Federal de São Carlos, 2008-07-30)
Sugohara, Renato Takeshi
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Iga, Ione
;
https://lattes.cnpq.br/8934634344275868
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https://lattes.cnpq.br/8807948509480699
In this work, we present Absolute Elastic Differential (SCDE), Integral Elastic (SCIE) and Momentum-Transfer (SCTM) Cross Sections for electron scattering by n-Butane (C4H10), Benzene (C6H6), Methanol (CH3OH), Ethanol (C2H5OH), 1-propanol (C3H7OH) and 2-propanol (C3H7OH). The measurements were performed for incident energies of electron in the range of 200 eV to 1000 eV. The methodology used is based in the crossed electron beammolecular beam geometry. The technique used for the normalization of measurements is the Relative Flow Technique. For better understanding of the kinetics involved in the gas flow rate, a systematic study was performed for the noble gases: He, Ne, Ar, Kr e Xe at various pressures, determining how to obtain these data through the decay of pressure as a function of time. The absolutes values of DCS, ICS and MTCS obtained experimentally were compared with values calculated by the Independent-Atom Model (MAI) and the Additivity Rule (RA).
Desenvolvimento de método analítico com emprego da espectrometria de absorção atômica para a determinação de Cd, Fe, Pb e Zn em amostras de interesse alimentício
(Universidade Federal de São Carlos, 2008-07-31)
Col, José Augusto da
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Pereira Filho, Edenir Rodrigues
;
;
https://lattes.cnpq.br/2190255150658571
Analytical chemistry plays a fundamental role in proposing fast and reliable procedures to analyze food samples. Proper selection and introduction of complementary foods reduces the vulnerability to micronutrient deficiencies. This study aimed to propose a sensitive approach for the promotion of adequate food supplements regarding Cd, Fe, Pb and Zn contents. For the development of this method, factorial design was used for experimental conditions optimization. These metals were determined using Flame Atomic Absorption Spectrometry - FAAS (Fe and Zn) and Thermospray Flame Furnace AAS (Cd and Pb). In TS-FF-AAS, a nickel tube is used as atomizer; since the sample is totally introduced into the tube, an increase in method sensitivity is obtained. Besides, flame residence time is extended, increasing efficiency of atomizing processes. Additionally, a simple procedure mixing the sample (100 mg) with 0.1 mol/L HCl was proposed. In food analysis, limits of detection (LOD) of 0.6, 100, 6.0 and 32 µg/L for Cd, Fe, Pb and Zn were obtained, respectively. Standard Relative Deviations (RSD) for elements Cd (n = 14), Fe (n = 3) and Zn (n = 19) were of 7.0, 5.5 and 6.0%, respectively. Analytical frequency of the method was of 28 determinations per hour with an analytical speed of 8 samples per hour (from sample preparation to determination). All determinations were performed with the same atomizing tube, which, even after 2270 determinations (around 76 h), did not present sensitivity losses. Cadmium and Zn showed suitable results when a bovine liver certified sample (SRM 1577b) was studied and the Fe content was strongly correlated to the size of the particle. Toxic metals Cd and Pb were not detected in the studied food samples. Regarding the essential elements, there was no increase in the Fe and Zn when the supplement is used. Information about food quality could be obtained, and the proposed method fits the purpose.
Sistemas logísticos : estudos de caso em três cadeias de suprimentos no segmento de motores para automóveis
(Universidade Federal de São Carlos, 2008-07-31)
Bonadio, Patricia Viera Grizola
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Alves Filho, Alceu Gomes
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https://lattes.cnpq.br/7885557554922569
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https://lattes.cnpq.br/6645440914763919
The worldwide (and thus Brazilian) automotive industry has undergone a process of important changes. Specifically in Brazil, the set up of new automakers, the consolidation and denationalization of the auto parts, and phenomena like the lowdisplacement engines have brought major strategic implicates to those companies, as well as to the supply chain to which they belong. Considering such implications, it is plausible to accept that several organizational elements were strongly impacted, including Supply Chain Management and Logistics. In this sense, the work has the prime objective to identify and analyze the logistics of three car-engine assemblers and some of their first and second- tier suppliers, discussing the relations between the logistics of each assembler and its suppliers in each supply chain studied. The hypothesis was formulated through literature review on the issues concerning this theme was carried out, as wells as a field research. Such research comprised case studies in three chains, led by assemblers with distinct strategies, with different levels of vertical interaction, representing distinct configurations. The case studies were conducted in the three assemblers and some of their suppliers (from the first and second tiers, in each chain), base don semi-structured interviews. The results indicate that, in general, the chain in function the structure and relations with supply implement logistics systems different.
Monitoramento in-line da formação de nanocompósitos PP/MMT via intercalação no estado fundido
(Universidade Federal de São Carlos, 2008-08-04)
Bertolino, Marcelo Koga
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Canevarolo Júnior, Sebastião Vicente
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https://lattes.cnpq.br/4153664441338178
The aim of this work is to monitor in-line, using an optical detector fitted at the extruder die exit, the formation of PP/MMT nanocomposites during polymer melt compounding. The intensity of the detector´s signal is dependent of the clay type (organofilization treatment), concentration and particle size, and so it is possible to monitor the presence of the clay tactoids due to their light extinction. The MMT clay is added as a pulse with constant weight into the PP extrusion flow and its presence is followed by the optical detector at the die exit. The data comes out as the common residence time distribution curves having its maximum intensity dependent upon the clay average particle size. On clay exfoliation the size of the tactoids are reduced to levels below the minimum particle size for producing light extinction and so the signal intensity reduces as the nanosize composite is formed. X-Ray diffraction analyses are used as offline monitoring of the nanocomposite formation. The results show that it is possible to use the optical detector to monitoring in-line the formation of nanocomposites.
A mídia impressa na promoção de discursos sobre políticas de igualdade racial : o negro e a revista Raça
(Universidade Federal de São Carlos, 2008-08-04)
Braga, Amanda Batista
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Sargentini, Vanice Maria Oliveira
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https://lattes.cnpq.br/1406919572611392
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https://lattes.cnpq.br/6466537417099357
Notre recherche problématise les discours qui soutiennent la construction de l égalité raciale au Brésil (ou bien, l effort pour), représentés par des énoncés sur les Politiques d Actions Positives transmis par les médias imprimées. Ces politiques represéntent une nouvelle façon de combat au préjugé au Brésil grâce à l adoption, a partir 1996, des politiques d identité, au détriment des politiques d intégration. Ainsi, le combat au racisme est mené selon une optique affirmative, en ratifiant de manière positive, les différences par les biais du discours de la fierté noire. Nous avons comme objectif débattre la trajectoire discoursive des ces politiques, en analysant comment ces discours sont produits, soutenus ou modifiés, par de médias imprimée et de quelle façon ils construisent des identités. Le corpus de notre recherche est constitué, plus particulièrement, par les discours qui sont inscrit dans le magazine Raça Brasil. Ce magazine a été publié, pour la première fois, en septembre 1996, à l apogée de toutes les discussions sur la question raciale au Brésil. Il se présente comme Le magazine des noires brésiliens, dont le but est celui de redonner aux noirs l estime de soi et de visibilité dans le marché médiatique et de la mode, donc, ouvrir une voie pour la valorisation des races qui ne soient que basée sur le combat au racisme, mais sur l affirmation de l identité. Avec le but de comprendre et de discuter de la production de ces identités dans les médias, surtout dans le magazine Raça, nous avons essayé de lancer quelques lumières sur le rapport établi par le biais du discours entre les noires et son esthétique. Dans ce context-là, nous trouvons dans le signe du cheveu crépu, frisé, un symbole producteur des signifiés pluriel, variable en accord avec les conditions de production discursifs. Basées sur ce contexte de pouvoir dans lequel s inscrit dans les discours médiatiques les rapports de gens noirs avec son cheveu, nous voulons démontrer comment les discours sur les usages des cheveux, et ainsi les sens qui lui sont attribués, font partie du processus de construction d une certaine identité. Notre recherche est, donc, une analyse des discours des politiques affirmatives, des rapports de pouvoir qui les traversent et des modes de production d identité qui sont inscrit dans les médias imprimées.
Influência da incorporação de aditivos nas propriedades do Poli (Hidroxibutirato-co-hidroxivalerato) - PHBV
(Universidade Federal de São Carlos, 2008-08-05)
Brunel, Daiane Gomes
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Agnelli, José Augusto Marcondes
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https://lattes.cnpq.br/7592090152400440
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https://lattes.cnpq.br/3739421391346977
The concept of environmentally correct products has been exhaustively discussed and, today, the use of biodegradable polymers appears as a feasible alternative for the problem of inadequate disposal of plastic waste products. Poly(hydroxybutyrate) PHB and the copolymer poly(hydroxybutyrate-cohydroxyvalerate) PHBV are among the main members of the class of biodegradable polymers, which are thermoplastic polymers produced from a renewable source and 100% biodegradable. However, PHB and PHBV still present several limitations, such as stiffness and brittleness, low thermal stability, and a narrow process window. However, the thermal and mechanical performance of PHB and PHBV can be improved through the use of additives. In view of this fact, the objective of this study was to produce materials with properties optimized through the incorporation of a plasticizer, nucleant and thermal stabilizer to the PHBV copolymer. The formulations were subjected to the following tests: tensile and notched Izod impact tests, melt flow index, differential exploratory calorimetry (DSC) and thermogravimetry (TG). Additivation of the copolymers proved effective, usually resulting in adequate processability due to the presence of the nucleant and the improved physicomechanical properties provided by the plasticizer. The thermal stabilizer proved dispensable since the stability of the PHBV was not improved. A comparison was made of the results obtained in some properties for the two copolymers with different hydroxyvalerate contents. The copolymer containing more HV proved better than the other, even displaying greater compatibility with the most efficient additives. The biodegradability was evaluated based on mass loss, alterations in the mechanical tensile properties, and SEM analysis after 180 days in organic soil. The additivated formulations presented higher mass loss than the pure copolymer, indicating the feasibility of producing a copolymer with adequate physical and mechanical properties combined with the desired biodegradability.
Modelagem fuzzy usando agrupamento condicional
(Universidade Federal de São Carlos, 2008-08-06)
Nogueira, Tatiane Marques
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Camargo, Heloisa de Arruda
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https://lattes.cnpq.br/0487231065057783
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https://lattes.cnpq.br/0851148137941240
The combination of fuzzy systems with clustering algorithms has great acceptance in the scientific community mainly due to its adherence to the advantage balance principle of computational intelligence, in which different methodologies collaborate with each other potentializing the usefulness and applicability of the resulting systems. Fuzzy Modeling using clustering algorithms presents the transparency and comprehensibility typical of the linguistic fuzzy systems at the same time that benefits from the possibilities of dimensionality reduction by means of clustering. In this work is presented the Fuzzy-CCM method (Fuzzy Conditional Clustering based Modeling) which consists of a new approach for Fuzzy Modeling based on the Fuzzy Conditional Clustering algorithm aiming at providing new means to address the topic of interpretability of fuzzy rules bases. With the Fuzzy-CCM method the balance between interpretability and accuracy of fuzzy rules is dealt with through the definition of contexts defined by a small number of input variables and the generation of clusters induced by these contexts. The rules are generated in a different format, with linguistic variables and clusters in the antecedent. Some experiments have been carried out using different knowledge domains in order to validate the proposed approach by comparing the results with the ones obtained by the Wang&Mendel and conventional Fuzzy C-Means methods. The theoretical foundations, the advantages of the method, the experiments and results are presented and discussed.
Contribuição do sistema de gestão empresarial (SGE) à efetivação da estratégia de produção
(Universidade Federal de São Carlos, 2008-08-06)
Gonzalez, Cleber Camacho
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Nogueira, Edemilson
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https://lattes.cnpq.br/4528400534946550
This work assumes that the success of an enterprise can be reached out more easily if the strategic hierarchies are respected. Thus, the decisions referring to the operational area ought to follow the paths proposed by the operation strategy, which should be subordinated to and coherent with the corporative strategy. Having this as a main basis, this study focuses on the strategic objectives of operations and, by means of case studies, it aims at verifying the contribution of enterprise management system (EMS) to its elaboration. The cases were studied aiming at knowing the performance objectives most valued by the company administration and the production function too. Next, this work studies in the operational area which traits of a EMS can mostly contribute in the effectiveness of these strategic objectives. Finally, an inventory about the utilization of the EMS is elaborated and a comparative analysis is carried out so that it is possible to identify the adequacy level existent. In order to get the reader acquainted to the themes discussed a bibliographical review was made and it covers Operation Strategy, Enterprise Management System and the Strategic Alignment between them. By the end of this study, it was possible to observe that the enterprise strategy has been communicating efficiently with the operational area and that the utilization of EMS contributes to the strategic effectiveness of operation. Nevertheless, it can be realized that this contribution could be more relevant in case the alignment between Operational areas and IT were worked out more elaboratedly. In relation to the alignment level, analyses did not show significant differences neither among the companies researched in spite of the fact they belong to different action areas, nor among different EMS or their versions.
Purificação de penicilina G por adsorção em resinas hidrofóbicas
(Universidade Federal de São Carlos, 2008-08-06)
Barros, André Nogueira Castro de
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Giordano, Raquel de Lima Camargo
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https://lattes.cnpq.br/8455531675596427
The separation of biotechnological products is an area of great economic importance once it represents the majority of the cost of this product. On industrial production of penicillin G (penG), the separation of the antibiotic has been made by extraction on organic solvent. However the decrease on the use of these solvents has become imperative in many chemical processes, caused mainly by environmental issues, which has motivating the pharmaceutical company PRODOTTI S/A, penG producer, on the research of new and less environmental aggressive ways to obtain this substance. Adsorption is one of the methods of concentration/purification most used by the chemical industry and it is based on the attraction exercised over the product (liquid phase) by a solid phase. The project sponsored by UFSCar/Prodotti/FINEP in progress has as one of its aims the study of the technical availability of substitution of extraction of penG by solvents for extraction by adsorption in hydrophobic resins. The penG, which is a weak acid, has therefore a favorable adsorption in low pH values. Nevertheless, penG can degrade itself under such conditions of pH, being required, in this way, adequate conditions for the operation. Therefore, the objective of this assignment was evaluate the influence of pH and temperature on the efficiency on adsorption of penG by hydrophobic resins, seeking conditions for maximum efficiency that do not result in degradation. Initially, it was necessary to develop the methodology that could allowed that analysis of a huge amount of penG samples in culture medium, which means that the penG could be analyzed in the presence of other nutrients and also could be distinguished between the intact and the degradated form. Some methods such as CLAE, iodometric and bioassay were analyzed and the conclusion was the CLAE method was necessary and also was able to quantify the penG s degradation rate. This features allowed the studies of penG s stability when exposed to different value pH and temperatures, the maximum half-life that it was stable in each condition and the time of growth, which means that it was possible to determine the time that the variation in the medium s concentration that did not affect the quantification of penG. Nevertheless, the CLAE method is very expensive to be applied to a large number of samples originated from culture medium. With this in mind, a new methodology was developed based on the complete hydrolysis of penG catalyzed by the penicillin G acilase, and this reaction proved to be precise and reproducible, reasons for being chosen in the later steps of this study. The efficiency of adsorption of penG was evaluated in the resins XAD-4, XAD-7, XAD-761 and activated carbon, and the XAD-4 resin has shown to be the most efficient with little increment of efficiency at pH 4.0 (44%) when compared to pH 6.0 (36%). Therefore, the XAD-4 resin was studied for parameters such as adsorption kinetics and the isotherms of adsorption were determined in different value of pH and temperatures. The Langmuir s isotherm had the best fit into the data collected in all the conditions, with maximum value of qmax = 595.06±51.54 mg penG/g resin, at pH 4 and 4°C. In order to analyze the adsorptions in value of pH lower than 4.0 without the occurrence of penG s degradation that usually occurs at high concentrations of this molecule and at value of pH lower than 4.0, two strategies referring to the adsorption conditions were studied. For the first one, the fermentative broth s pH is adjusted and right after this same broth is maintained in contact with the adsorbent. For the second method, the adsorbent was add to the fermentative broth at a pH of 7.0 and with the adsorption process the pH was reduced until reach the complete adsorption of the penG. The last process showed a better efficiency of adsorption of 0.77g penG/g resin and productivity of 0.31 g penG/g resin/hour at pH 4.0, meanwhile the direct adsorption at pH 4.0 had an efficiency of 0.548g penG/g resin (0.548 g penG/g resin/hour). The second strategy with the gradient is better since it increases the efficiency and decreases the productivity of the process. The results showed that the ideal situation would be to work with pH values even lower than 4, but elevated concentrations of penG will lead to the degradation of the antibiotic in this pH range. The desorption of penG was studied using a technique of experimental planning and analysis such as pH, temperature and composition of mixture water/ethanol. The results showed that to obtain a maximum desorption, the process must be effectuated at 8°C and utilizes as eluent a mixture of 82.5% ethanol and 17.5% water on a pH of 6.2.