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Influência da lesão condral na concentração de glicosaminoglicanas sulfatadas no líquido sinovial
(Universidade Federal de São Carlos, 2006-02-28)
Cintra Neto, Paulo Felix de Araujo
;
Rosa, Stela Márcia Mattiello Gonçalves
;
https://lattes.cnpq.br/1406279816228350
Objective. To evaluate the influence of sulfated glycosaminoglycan (GAG) concentration in synovial fluid from individuals with chondral injuries, either isolated or associated with anterior cruciate ligament injury or meniscal injury, and check for an association between time since injury and the degree of chondral injury. Material and Method. Twenty-nine adult subjects (25 men and 4 women, mean age 38.3 ± 10.9 years) were selected. Samples obtained from all subjects were quantified to determine the GAG concentration using dimethylmethylene blue dye. The degree of chondral damage was macroscopically evaluated by arthroscopy and rated according to the International Cartilage Repair Society (ICRS) classification. Results. Significant differences were found concerning the GAG concentration in the control group compared with the other groups (p<0.05). No significant differences were found between the studied groups concerning time since injury and degree of chondral damage according to the ICRS. A strong correlation was found between GAG concentration and time since injury in the chondral injury group (r= -1). Conclusion. Damage to articular structures seems to be the determining factor in the change of synovial fluid GAG concentration, being higher in isolated chondral injury. When associated with anterior cruciate ligament rupture and/or meniscal injury, it will promote a tendency to fall, and is not related to sex, age, time since injury and degree of chondral injury in all groups studied.
Estimativa da infiltração e do afluxo devidos à precipitação na rede de esgoto sanitário em município de pequeno porte
(Universidade Federal de São Carlos, 2006-02-28)
Festi, Aparecido Vanderlei
;
Barbassa, Ademir Paceli
;
https://lattes.cnpq.br/2979012440240781
The main purpose of this work was to identify and to estimate the rainfall derived infiltration and inflow (IADP) into the sewer in a small city and to do an analysis of their influence on this collection system. This work was composed by field measurements on the sewage flowrate output and volume arriving to the Sewage Pumping Plant Station, simultaneously to the collection and measurement of rainfall on the corresponding same urban watershed area of the Borborema, in São Paulo State. The existing methodologies were divided in the follow steps: choosing and characterization of the working field; data collection of the sewage volume and flowrate; collection of the rainfall data; choosing and characterization of the data collected; employment of existing models and methodologies useful to the present available data, in order to derive the underground water infiltration rate and the overflow occurring in the sewage colletion network. The volumetric and percentile IADP were quantified. The constant unitary rate (TUC) was also estimated, by several ways. The results allowed obtaining mathematical formulations to derive the IADP and TUC of the Borborema s sewage network. Such mathematical formulations are suitable to be applied in urban areas of cities of a similar to that of Borborema. It was estimated that the IADP can generate flowrates 2,5 times greater than the sewage flows in dry weather and infiltration rates in the sewage network similar to those adopted for system design. The work allowed to estimate how complex are the infiltration and inflow of stormwater in the sewer network. The methodologies applied were quite simple and may be easily applied in other cities.
Projeto, construção, testes e operação de um extrator de óleos vegetais
(Universidade Federal de São Carlos, 2006-03-02)
Tavares, Jaciomar Alves
;
Silveira, Ana Maria da
;
https://lattes.cnpq.br/4807254028571537
;
https://lattes.cnpq.br/3191021230710929
Brazil is a rich country in biodiversity holding a great variety of plants, being one of the main constituents - oil that has been searched by the industries, especially, pharmaceutic, food and cosmetic. Among the plants with these characteristics is the well -noted ginger, that has been used in treatments, from stomach to rheumatism problems, in culinary as condiments and also in perfumery. Depending on the importance and application of the essential oil, in literature, some types of extractors are found, being able to be cited the distillers of the types Clevenger, soxhlet and the one that uses supercritical CO2. Analyzing these extractors it was verified that these present advantages and disadvantages that motivated this work, that has as objective to develop, project, construct and operate an equipment that allows the extraction of the essential oils, using the principle of dragging through vapor and that makes it possible the manipulation of the variable pressure and temperature. The developed and constructed equipment is composed by a boiler, a chamber of extraction with three trays and a distiller, operating itself in the following conditions: pressure in boiler 1.2 kgf/cm² the 3,6 kgf/cm²; pressure in the chamber of extraction - 0,4 kgf/cm² the 3,6 kgf/cm²; temperature: 75°C 140°C; average outflow of distilled in 0,831l/h and a average outflow of water in the distiller of 125 l/h, trays - one, two and three and mass of ginger - 200g, 400g, 600g and 1200g. Optimum result gotten in this extractor was using three trays and mass of 400g of ginger, extracting a mass of 0,965g of oil, what it corresponds to a 1,7% text. In the comparison between these results and the gotten ones for the Clevenger, the extracted oil text was 2,77 and 1.70%, respectively, showing that the projected and constructed equipment extracted 63% more than the oil, in the same conditions and with 3 hours to less of operation.
Estudo de procedimentos analíticos para determinação de Cr(III) e Cr(VI) em amostras sólidas
(Universidade Federal de São Carlos, 2006-03-02)
Matos, Wladiana Oliveira
;
Nóbrega, Joaquim de Araújo
;
https://lattes.cnpq.br/8833989058164529
The legislation is evolving towards the establishment of restrictions to the concentration of Cr(VI), the most toxic redox form of chromium, in solid materials. This aspect has stimulated the development of sample preparation procedures for redox speciation analysis of chromium in solid samples. In the work here described it was studied procedures for Cr(VI) extraction in solid samples using alkaline solutions. Molecular absorption spectrophotometry based on 1,5 - diphenylcarbazide as chromogenic reagent was used for the determination of Cr(VI). The quantification of Cr(III) was carried out by the subtraction of the total chromium concentration and the concentration of Cr(VI). The samples employed were: soils, cements, cementrelated materials, nutritional complements and metallic components. The extractor solution composed by 0.10 mol L-1 Na2CO3 presented good performance for solid samples. Tests of stability of Cr(VI) indicated that reduction of Cr(VI) to Cr(III) did not occur in the adopted extraction conditions, even in the presence of significant amounts of Cr(III). The diphenylcarbazide method presents good sensitivity for the determination of Cr(VI) in extracts, however the presence of organic matter in the soil samples caused interferences. The total chromium concentrations were determined using either FAAS or ICP OES after complete decomposition of the samples. Sample preparation procedure for total chromium determination was implemented according to the type of sample. Cement samples and cement-related materials were decomposed by fusion. On the other hand, all the other samples were microwave-assisted digested using high pressure vessels. The main limitation of the studied procedures is the evaluation of accuracy because of the lack of standard reference materials.
O conceito de n-varifold e EDP
(Universidade Federal de São Carlos, 2006-03-03)
Paula, Fernanda Gonçalves de
;
Nascimento, Arnaldo Simal do
;
https://lattes.cnpq.br/6609243657130387
The goal of this work is the detailed study of some topics of Geometric Measure Theory, giving special attention to the n-varifold concept and illustrating its use in the asymptotic behavior of critical points of the energy functional for the van der Waals-Cahn-Hilliard theory of phase transitions.
Análise química de materiais argilosos e refratários modificados durante moagem por espectrometria de emissão óptica com plasma acoplado indutivamente
(Universidade Federal de São Carlos, 2006-03-03)
Santos, Mirian Cristina dos
;
Nóbrega, Joaquim de Araújo
;
https://lattes.cnpq.br/8833989058164529
The main goal of this thesis was the investigation of alternative procedures for chemical analysis of refractory materials and clays using an inductively coupled plasma optical emission spectrometry (ICP OES) with axial view by direct analysis of slurries and microwave-assisted alkaline digestion. The preliminary experiments of this work focused the introduction of slurries into the ICP OES with axial view and evaluated the effects caused by the particle size distribution on the intensities emission signals. Afterwards, a grinding method in which solid samples were ground together with chemical modifiers was developed. The chemical modifiers studied were LiBO2 and Na2CO3, since they are frequently used as fluxes in fusion procedures, and NH4Cl, ascorbic acid, and graphite. The effects of the chemical modification on the intensities of emission signals and the grinding time required for obtaining greater intensities emission signals were evaluated. The chemical modification procedure was implemented in order to promote the formation of new compounds with thermal properties different of the original materials. The synthesis of less refractory compounds would favor the process of atomization-excitation of the chemically modified materials in the direct analysis of slurries, and it would also facilitate the digestion of these materials. The effects of the chemical modification were also evaluated by using X-ray diffraction and thermogravimetric analysis. The direct analysis of chemically modified materials by ICP OES required the investigation of several calibration methods based on different approaches: use of aqueous reference solutions, calibration with slurries prepared using certified reference materials, and calibration using the generalized standard addition method. The calibration is the most critical aspect in the direct analysis of slurries by ICP OES, because is critically dependent on the particle sizes and of the thermal behavior of the several mineralogical phases of each material. On the other hand, microwave -assisted digestion was investigated in two alkaline media: KOH and NaOH. Applying a paired t-test it was shown that results were in agreement at 95% confidence level with those obtained by microwave-assisted acid digestion. The values of the detection limits and signal-to-background ratio obtained for the two microwave -assisted procedures were compared, and the alkaline digestion has shown adequate performance for the digestion of the chemically modified materials.
Histamina facilita a aprendizagem em uma tarefa de escolha espacial em Carassius auratus
(Universidade Federal de São Carlos, 2006-03-03)
Santos, Fernanda Romaguera Pereira dos
;
Mattioli, Rosana
;
https://lattes.cnpq.br/5694498670428619
This work intended to investigate in forebrain ablated Carassius auratus the effect of the H1 receptor blockade in a spatial choice task using a T-maze test with positive reinforcement. Sixty-nine goldfish were submitted to surgery for removal of both telencephalic lobes five days before the beginning of the experiment. A T-shaped glass aquarium, which had two feeders located at the extremities of the long arm, was employed. One of the two feeders was blocked. The experimental trials were performed in nine consecutive days. Each fish was individually placed in the short arm and confined there for thirty seconds, then it was allowed to swim through the aquarium to search for the food for ten minutes (maximum period). Time to find food was analysed in seconds. Animals were injected intraperitoneally with chlorpheniramine (CPA) at 16 mg/kg of body weight or saline after every trial, ten minutes after it had been replaced at house aquarium. Data were analyzed via a three-way analysis of variance (ANOVA) with repeated measures, and post hoc comparisons were analyzed using the Student Newman-Keuls test (p<0.05). All the training latencies of A-SAL group were significantly higher than latencies of S-SAL group (p<0.05). S-SAL group showed a significative decrease in latencies at the second trial and maintained that reduction until the end of the experiment (p<0.05), S-CPA group demonstrated a decrease only after the fourth trial (p<0.01), A-SAL group showed reduced latencies after the fifth trial (p<0.05), and ACPA group did not showed any difference between training latencies. Thus, our results showed that CPA seems to impair the consolidation of memory either on telencephalon ablated animals and in sham-operated ones. Furthermore, this work supports evidence that histamine plays a facilitatory role in learning and memory processes of a spatial task through its action in primitive structures of the brain in teleost fish.
Germes de funções sobre variedades analíticas
(Universidade Federal de São Carlos, 2006-03-03)
Silva, Marcela Duarte da
;
Tomazella, João Nivaldo
;
https://lattes.cnpq.br/0051564735964760
The study of analytic germs of functions (Cn, 0) → (C, 0) under R - equivalence relation is a central point in Singularity Theory and the information we have in this direction is very rich. In this dissertation we have a study similar for an equivalence relation which preserve certain analytic variety X, the RX - equivalence.
Uso de métodos bayesianos em testes de vida acelerados no controle da qualidade de produtos industriais
(Universidade Federal de São Carlos, 2006-03-03)
Vieira, Denilton da Silva
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Achcar, Jorge Alberto
;
https://lattes.cnpq.br/3125027713681936
In this work, we introduce a Bayesian approach for quality control of industrial products, assuming units in test under stress levels higher than the usual level. We assume di¤erent distributions for the lifetimes of the units under a type II censoring mechanism and a general stress-response model that includes the usual accelerated life test models. Using a predictive density of a future observation, we present some criteria to be used by engineers in the quality control of a batch of industrial products. These criteria permit a choise for the best time in test or for the best stress level in the quality control test. The quality control procedure is based on the observed proportion of failures tested during a specified time and a specified stress level. We use the software WinBugs (Spiegelhalter et al, 1999) to obtain the posterior summaries of interest. keywords: Accelerated lifetime test, Bayesian Inference, Markov Chain Monte Carlo, Quality Control.
Uma modificação da extensão do algoritmo AID para modelos lineares generalizados usando reamostragem Bootstrap
(Universidade Federal de São Carlos, 2006-03-03)
Presotti, Cátia Valéria
;
Barreto, Maria Cecília Mendes
;
https://lattes.cnpq.br/2218053283392257
One of the most frequently situation found by researchers is to find groups of similar individuals. The cluster analysis is a set of statistical techniques that identify mutually exclusive subgroups or classes over individuals, based on their similarity. When then main is to group means of treatments we can use contrasts, multiple comparitions or clustering techniques as the SCOTT-KNOTT test and AID (Automatic Interaction Detector) technique. In this work we focus on the comparition of the simulated power function of the asymptotic test and also of the bootstrap test for the extension of the AID algorithm for generalized linear models. The bootstrap power function over main the asymptotic power when the number of binomial sample is equal to one, and the number of treatments is equal to 8 and 12, in a completed randomized experiment with a single factor for binomial variables.
Auto-relato de erros em tarefas de leitura: efeitos de um treino de correspondência
(Universidade Federal de São Carlos, 2006-03-06)
Domeniconi, Camila
;
Rose, Julio Cesar Coelho de
;
https://lattes.cnpq.br/3386857761295187
When children with a history of school failure report on the outcomes of reading responses, most of them tend to report mostly correct responses, even after they make mistakes. This study investigated variables influencing correspondence in these reports and attempted to train correspondence to ensure accurate reports of errors, as well as of correct responses. Experimental sessions presented series of words on a computer screen. The computer dictated the correct word and children selected a green or a red window to report that the response had been correct or wrong. Baseline sessions showed that reports of errors as correct responses increased as a function of error probability. Training sessions then reinforced correspondence, providing points contingent to selections of the green window after a correct response and selections of the red window after an error. Correspondence quickly increased and was maintained in subsequent baseline sessions. Correspondence training was effective to establish accurate reports of errors in these children.
Aprender a ensinar Geografia: a visão de egressos do curso de Pedagogia da UEFS (Univerisdade Estadual de Feira de Santana)
(Universidade Federal de São Carlos, 2006-03-06)
Braga, Maria Cleonice Barbosa
;
Tancredi, Regina Maria Simões Puccinelli
The present study is at the scope of investigation which search to understand how it s been developed the teaching and learning processes of the specific didactics in Pedagogy Training Course for experienced teachers. More effectively, its is directed to the understanding of teaching and learning at the subject Geography on the Pedagogy First Initial Series of Primary School course, at the Universidade Estadual de Feira de Santana (UEFS). Even though many courses have been implanted in the past few years involving this public, its still rare the researches dedicated to the understanding of its contributions to these teachers practices. These scarcity, together with a particular interest in contribute with the deepness of the question, is the reason for me to do this work, guided for the following question: How do the egresses from the degree in Pedagogia Séries Iniciais do Ensino Fundamental at UEFS, describe and analyze the Geography teaching developed at the course, considering the contributions to the development of their practices inside the classrooms? The theoretical references adopted were: to discuss teaching learning and professional teaching knowledge, we considered the contributions from Maurice Tardif, Marcelo Garcia, Pérez Gómez and, to discuss the different approaches in Geography we adopted the works of William Vesentini, Helena Callai, Lana Cavalcanti, Nídia Pontushcka. In order to do the investigation, we selected seven egresses who were teaching the subject Geography at the first initial series of Primary School since they have finished their degree. The main data collection instrument was the individual interview together with a questionnaire, using a qualitative approach as a research reference in their paths as students of the Basic Teaching and in the course of Pedagogy, in UEFS. It was clear the change in the way of to understand and to teach Geography. The first was the one of the book, of the copy, of the "decoreba"; it was the learned Geography, just, to answer the subjects of the proof. The second was developing of another perspective, characterized essentially by his/her relationship with the concrete life, with the reality of a world that is unequal and unjust. Besides, the data revealed some changes in practice of the current participants of the multiple relationships with the knowledge locked in the degree, besides in the discipline Ensino de Geografia. But they had disclosed also that not learning had of contents specific (concepts, facts, methods of education) and nor of a conception of formation based in the theorypractical relation that they allowed them to develop an education of analysis, critical and reconstruction of the proper teaching exercise.
O que dizem os professores das 4as séries do ensino fundamental sobre o ensino de ciências neste nível de escolaridade
(Universidade Federal de São Carlos, 2006-03-06)
Guzzi, Igor de Souza
;
Pierson, Alice Helena Campos
;
https://lattes.cnpq.br/4959438463921122
More and more, the society has required citizens to act in a world which scientific and technology knowledge is extremely worth. The evolution of these knowledges works as a modern world´s mirror, which, indeed, reflects all the progress that conduced to the development of the actual society, consisted by the amazing velocity the information is spread, and by the incredible science dynamism. In this way, make people get closer from informations about science takes an important and challengeable role. Important since it leads you to a world comprehension and its information; challengeable because of the complexity that involves the teaching and learning task. The science studies has to act as a contributor to the reality comprehension, mainly in understanding the natural events, stimulating questions about the differents ways the interventions can modify them. In that case, the investigation of the questions that covers the learning process of teaching modality since basic grades becomes indispensable, as we think about the developments coming from critical people who are acting directly on the society. The main purpose of the present work was to obtain elements that could bring possibilities of proofs, reflections and discussions around the science teaching in basic grades, especially on the fourth grade, which is the focus of this research. For that, it was necessary an approximation to science teaching history and to the different sources teachers acquire to be able to get the knowledges which state their praticals, involving questions about the science curriculum, materials used within the classes and others aspects that leaded to a bigger approximation to the process of teaching and learning. The investigation started from a theoretical reference based on teacher s knowledges. Therefore, a better comprehension of how teachers relate with the knowledges that are used within their science classes and how those knowledges are acquired were better understood.
Paradoxos do homem: um estudo sobre a condição humana em Pascal
(Universidade Federal de São Carlos, 2006-03-06)
Nascimento, Juçara dos Santos
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Ferraz Neto, Bento Prado de Almeida
;
https://lattes.cnpq.br/0084436724293824
Desenvolvimento de filmes nanoestruturados de polímeros condutores aplicados a sensores gustativos para avaliação de cafés
(Universidade Federal de São Carlos, 2006-03-08)
Paula, Gustavo Figueira de
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Mattoso, Luiz Henrique Capparelli
;
https://lattes.cnpq.br/5839043594908917
;
https://lattes.cnpq.br/0634496933960503
This work aimed the investigation of ultra thin, polymeric film compositions made by the layer-by-layer deposition technique capable of coffee quality classification accordingly to stablished standards, using electrical impedance measurements and the statistical method Principal Component Analysis. Films made of polyaniline, poly(o-ethoxyaniline), polypyrrole, poly(3,4- ethylenedioxythiophene), poly(hexamethylene biguanide), poly(sodium methacrylate), fatty acids and derivatives, and other materials were studied. Films were grown showing the applicability of these materials to self-assembly of sensors based on polymeric materials. It was verified that PANI and DBSA has a great potential as materials for sensor construction by such process due to high rates of film growing. Itl was also observed that PEDOT(PSS) alternated with PHMB(HCl) was the better material combination for coffee evaluation. Impedance measurements in broad spectrum and use of variance-based ranking factors allowed selection of optimum operation frequency for each sensor, aiming the classification of brewed coffee by Global Quality and bean type. With this strategy, it was also possible to determine those materials that presented the best responses. Experimentally, it was shown that coffee deposition occurs on the electrode surface during the time of measurements, and proved that the usual washing procedure was not efficient to remove all adsorbed coffee compounds, being necessary the washing with detergents. The results of this work allows the construction of a sensor array to classify commercial coffees by Global Quality, and the optimization of a sensor array specialized on defective beans, which previously could not be determined on commercial samples of roasted coffees.
Ecologia molecular, variabilidade genética, química e cultivo in vitro de Hesperozygis ringens Benth
(Universidade Federal de São Carlos, 2006-03-08)
Fracaro, Fernando
;
Echeverrigaray, Sergio
;
https://lattes.cnpq.br/5630031784004533
Hesperozygis ringens, belongs to Lamiaceae s family, it is an aromatic plant native from the South Brazil with its occurrence restrict south fields mainly in Caçapava do Sul, Alegrete and São Francisco de Assis. Due some activities agropastoris like continuous cleanness and burning to the renovation of grassland associate with some factors like low seed efficiency propagation, these spices are in extinction process. In order to evaluate the effect of these activities at the extinction process of this plant were used molecular markers RAPD and ISSR to evaluate the genetic variability, chemical variability of the essential oils and effect of the growing regulators in the micropropagation. With molecular markers we check a low gene flow between studied populations, with distinct genetic entities, sharing the samples in isolated clusters from Alegrete, São Francisco de Assis and Caçapava do Sul, the last one was evaluate in two populations A and B witch showed a larger gene flow between samples. The chemical variability data were confirmed by markers RAPD and ISSR, because they shared the populations in two isolated groups, characterized for to present compounds with low frequency like limonene and linalool in the São Francisco de Assis population, and the others were not present as sabinene in Caçapava do Sul. In the in vitro propagation the MS medium showed the best results supplemented with 13.2µM of benzyladenine and 2mg/l of silver nitrate, witch were used to avoid ethylene accumulation effect. The rooting showed limitation with low efficiency, but was obtained with carbonized rice back, with ¼ MS supplemented with IBA. Even with hardness the micropropagation can be an alternative for the propagation and preservations of this endangerous species. Based in this results of this work were discussed about environmental, evolution and conservation aspects.
A informática e a educação continuada de professores: analisando aprendizagens e processos
(Universidade Federal de São Carlos, 2006-03-08)
Simião, Lucélio Ferreira
;
Reali, Aline Maria de Medeiros Rodrigues
This research, of a qualitative nature, investigates aspects of the learning process of the teaching staff, in order to contribute to the continued in-service learning for teachers in the use of computers in their teaching practice. The preparation of teachers to work with computers in education has been occurring, usually, by means of courses given outside of the context of their work. However, this study seeks to analyze the possible contribution of a proposal of continuing education in the work place, to make possible new competence and abilities in the use of computers in the classroom. The study was carried out in a private school in the city of São Carlos, SP, and its central focus was the development of activities within the context of the reality of school and teacher, using software applications as teaching tools in the construction of projects. The methodology adopted is associated with a constructive-collaborative model of research and intervention, in which the people involved, teacher and pupil, play roles of a collaborative nature, as partners, in a multi-faceted relationship. The theoretic contribution established a relation among computer science, education and teacher training, emphasizing the advance of technology in education and the roll of the school and the teacher in relation to new and growing educational demands, in a constantly evolving technological scene. The data obtained indicated a concern on the part of the investigated teachers to appropriate for themselves skills that makes it possible for them to use computers in the classroom. They recognize the usefulness of the computer in teaching, however they point out some limitations, such as the lack of ability and the difficulty of developing educational activities using the computer, the lack of time available to learn to use the computer in view of other teaching demands, and the lack of equipment and educational software for use in the class room. It was evident that, in the training environment, the production of innovative educational practices came about through reflection on shared experiences. It was indicated that there is a need for the training programs for teachers to have as their axis the context of their use, and and for the creation of a culture that permits the teacher to become a critical user of technology, using it in her teaching, and becoming her own agent of change.
Influência de práticas de manejo de solo sobre os macroinvertebrados aquáticos de córregos: ênfase para o cultivo de cana-de-açucar em áreas adjacentes
(Universidade Federal de São Carlos, 2006-03-09)
Corbi, Juliano José
;
Strixino, Susana Trivinho
;
https://lattes.cnpq.br/1804083229761186
Brazilian colonization occurred without a specific planning and, as a consequence, natural resources, particularly forests, were greatly affected specially by economic interests. In the Brazilian history, the native land cover vegetation was removed, and substituted by agriculture, mainly of sugar cane and also pastures. In the State of São Paulo, the sugar cane culture has also being enlarged, with the annual production of the about 200x106 tons covering an area of 2.5x106 ha. The use of herbicides and fertilizers containing different concentrations of the metals Pb, Ni, Cr, Cd and Zn, during different periods of cultivation of sugar cane, in addition to the deforestation of riparian vegetation, have caused impacts on the hydric resources of the adjacent areas. In the present work, the influence of the agricultural activity, in particular, sugar cane culture, on stream macroinvertebrate communities was studied. Macroinvertebrates, sediments and water were surveyed in three periods: March/April, 2002; June/July/August, 2002; October/November, 2002. Thirty three samples were collected: 15 in streams with sugar cane culture, 12 in streams with riparian vegetation and 6 in pasture areas. The concentration of the dissolved oxygen was low in streams without riparian vegetation (sugar cane and pasture) when compared to preserved areas. The concentration of the metals Cu, Fe, Cd, Zn, Mn, Cr e Ni of the sediment were high in streams with sugar cane cultivation, with significant differences to Cu and Zn, when compared to forested streams. The streams located in the adjacent areas with sugar cane cultivation also present high concentration and frequency of occurrence of the 15 organochlorine compounds analyzed. In this study, 3365 organisms were collected, in which 54 Chironomidae taxa and 42 of other aquatic macroinvertebrates. The streams located in areas of sugar cane culture and pasture (opened areas) presented low taxa and a great participation of Chironomidae (78% of the total). In contrast, the streams located in areas with riparian vegetation presented a rich aquatic fauna with less participation of Chironomidae (60% of the total). The community index, in addition to other measurements, applied to the stream macroinvertebrates community of the 11 streams pointed out to major values of richness, diversity and biotic index to the streams located on forested areas, when compared to the streams located on areas with sugar cane cultivation and pasture. Overall our results indicated that deforestation of the riparian vegetation was the principal aspect that influenced the stream macroinvertebrate communities. The loss of the riparian vegetation in the streams located adjacent of the agriculture areas establish an environmental impact that results in a poor taxa richness and shows clearly the necessity of a suitable management of the hydric resources of the southeast region of Brazil.
Estudo da fluidodinâmica em leito fixo utilizando-se métodos numéricos de solução: escoamento monofásico de ar
(Universidade Federal de São Carlos, 2006-03-09)
Béttega, Rodrigo
;
Corrêa, Ronaldo Guimarães
Studies accomplished in the structure of tubular fixed beds proved that the porosity in these systems presents an oscillatory behavior along the radial direction. The non-uniformity of the porosity generates a behavior of the velocity profile, inside the bed, characterized by oscillations in the central region and a peak of larger width in the region close to the wall. This velocity profile determines the residence time of the reactants, for example, and presents a strong influence in the heat and mass transfer coefficients of these systems. In spite of the progress obtained in that subject, it is still difficult to obtain the measure of flow velocity inside the bed without causing disturbances in its structure. Due to this restriction, indirect forms of experimental measure of the velocity distribution in these systems have been proposed to evaluate the fluid dynamics inside the bed. The most common way to obtain, experimentally, the velocity distribution inside the bed is to measure it outside the bed, at a certain distance from its exit, and then infer it inside the bed by considering that the flow measured at this point maintains the fluid dynamics characteristics at the interface. Looking for an alternative way to infer the velocity profile inside the fixed bed, this work proposes a measure of the change in flow characteristics from the exit of the fixed bed to the point of experimental measurement. The measure proposed before takes into account the change in the radial mean velocity evaluated over an area close to the central part of the flow. This measure is based on simulated results accomplished between these two points, located outside the fixed bed, from an appropriated boundary condition at the interface. This boundary condition at interface is the result of other simulations performed inside the fixed bed, from a convenient model proposed for this region. Both simulations were accomplished by using a simulator developed in FORTRAN language, based on a CFD numeric technique for outside and a standard finite difference method for inside the fixed bed. The validity of the proposed procedure was verified by comparing the velocity distribution simulated at a position pointed out in an experimental measurement of the velocity distribution obtained in the literature, and with similar operational conditions. By doing this validation, it was established a relationship between the change in flow characteristics and the axial position of measurement. As a result, it was possible to infer how much of the flow characteristics in the interface are observed from the position chose for measurement along the axial direction of the flow. Better results were observed in systems with a high dimensionless D/Dp relation and low values of Reynolds number for the flow simulations accomplished in the exit area of the bed. Deviations from experimental data, varying between 2,97% and 30,23%, were verified for different operational conditions of the system. Through the central velocity simulation along in the empty tube axial position, were possible to map the empty tube influences on the flow in the fixed bed exit area, evaluating the difference of that central medium velocity with the calculated for the bed exit.
Existência global de soluções para uma classe de leis de conservação e algumas considerações sobre um sistema de leis de conservação
(Universidade Federal de São Carlos, 2006-03-09)
Ferreira, Ricardo Edem
;
Kondo, Cezar Issao
;
https://lattes.cnpq.br/0900348462714778
;
https://lattes.cnpq.br/1696477429814262
In this work, we will construct global solutions for a conservation law, due to C. M. Dafermos. Also we will discuss some properties for a class of systems of conservation laws, due to B. Rubino.