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Estratégias para a síntese de compósitos moleculares derivados de poliuretanas
(Universidade Federal de São Carlos, 2009-02-20) Libanori, Rafael Augusto Nicolosi; Leite, Edson Roberto; https://lattes.cnpq.br/1025598529469393; https://lattes.cnpq.br/5871415628285343
In this work, we investigated strategies to obtain polyurethanebased molecular composites containing metal oxide nanoparticles chemically attached to polyurethane polymeric chain. In Strategy 1, nanoparticles functionalized with OH organic groups were added in a typical reaction to obtain thermoplastic polyurethane. The obtained materials were transparent, presented brown-color and typical characteristics of thermoplastic polymers. The results revealed that the addition of functionalized nanoparticles plays an important role in the chain growth process, suggesting that nanoparticles OH organic groups are consumed during the polymerization process, forming a primary bond between the material components. However, it was not possible to identify that primary bond by the characterization methods used in this work. On the other hand, in the Strategy 2, efforts were spent on the development of methods to obtain functional organic molecules constituted by linear chains with silane groups in both ends (called here as connecting agents). The connecting agents were used as nanobuilding blocks in a condensation reaction with metal oxide nanoparticles in order to obtain a linear hybrid chain with alternated organic and inorganic blocks. Despite it was not possible obtain linear hybrid chain molecular composite, the results contributed to a better comprehension of the mechanism involved in that method, suggesting that the use small nanoparticles (< 10 nm) and large organic molecules (molar mass between 10.000 e 50.000 g/mol) is necessary to synthesize the linear hybrid chain. Furthermore, bifunctional nanoparticles must be used to avoid the formation of a tridimensional network by cross-linking processes.
Estrutura e funcionamento de copas em espécies arbóreas de cerrado com distintas fenologias foliares
(Universidade Federal de São Carlos, 2009-02-20) Souza, João Paulo de; Prado, Carlos Henrique Britto de Assis; https://lattes.cnpq.br/7561749470600567; https://lattes.cnpq.br/6366723862615278
The relationships among shoot inclination, light interception, photosynthetic capacity along shoot, biomass partitioning in leaves and shoots and the canopy structure were investigated in deciduous, semideciduous and evergreen tree species in Cerrado vegetation. The principal aim was to investigate the functioning and the structure of the canopies in cerrado tree species. The central hypotheses was that deciduousness is a trait strongly related to both canopy structure and functioning, and this relation could be revealed by morphological features of shoots, leaves, and by means of photosynthetic capacity along the shoot. Deciduous species produces only one cohort of leaf during the year at the end of the dry season. Slanting (plagiotropic) shoots in deciduous species could be one way to avoid the foliage self-shading since the bud unfold. One specific hypothesis was that deciduous species have plagiotropic shoots and the irradiance intensity and the photosynthetic capacity would be similar along shoot. The plagiotropic shoots in deciduous would allow high individual leaf area, high leaf area per shoot and one relationship between shoot-leaf in favor of leaves. On the other hand, the high leaf exposition to intense irradiance along shoot probably is one factor that imposes the shedding of the whole foliage at the dry season. Semideciduous and evergreen species produce leaves continuously during the year. The retention of the half of the foliage as in semideciduous even at the peak of dry season demands protection as the foliage self-shading along the shoot. Therefore, semideciduous and evergreen species have erect (orthotropic) shoots with evident foliage self-shading along the shoot. The light extinction along the orthotropic shoots could be one protection against excessive input of energy, especially in dry season. On the other hand, the dissimilar irradiance distribution along the shoot could result in significant difference about photosynthetic capacity between shaded basal and sunlit distal leaves on shoots. Semideciduous and evergreen species have higher number of canopy ramification than the deciduous species by reason of greater shoot emission at every season. This high canopy ramification in semideciduous and evergreen species could be revealed from one network representation with basic components as nodes and links. We supposed that links could be the shoots and nodes the nodal region where the shoots are emitted from the parental shoots. This representation could reveal structural differences in canopies of deciduous, semideciduous and evergreen species. These differences could be uncovered by the number of ramification and by the number of nodes in each leaf phenological group. Therefore, the link/node ratio and the frequency of shoots per node could reveal structural aspects significantly different across leaf phenological groups in 15 tree species studied here growing in a cerrado stricto sensu physiognomy.
As condições subjetivas e objetivas do trabalho docente no processo de inclusão de crianças na educação infantil : uma análise sob a perspectiva da Defectologia de Vigotsky
(Universidade Federal de São Carlos, 2009-02-20) Barreto, Selva Maria Guimarães; Mello, Maria Aparecida; https://lattes.cnpq.br/8338726751746542; https://lattes.cnpq.br/1495382719551990
The present study aimed identify and analyze the conceptions expressed by Early Childhood Education professors on the inclusion process of children with special teaching needs in the Basic Education Level based on the Defectology Theory structured by Vigotsky (1997) and recognize, analyze and comment the subjective and objective working conditions that subsidize the thoughts and actions executed by professors during the inclusion process of children with special teaching needs in Early Childhood Education in the city of Sao Carlos. Thus, primary retrospective document researches and contemporary writings were conducted, along with the association of secondary data gathering and analysis. Documentary sources were public (official documents and parliamentary publication) and particular documents, associated with the qualitative and quantitative descriptive exploratory field research. Data gathering occurred with the recording and transcription of two interviews conducted with six Early Childhood Education professors from the city of Sao Carlos. All interviewers graduated in Pedagogy and present a teaching assignment position for more than five years. They were examined with three analysis guidelines established upon the goals determined for the present research: guideline 1 -subjective working conditions of the interviewed professors; guideline 2 objective working conditions of the interviewed professors; guideline 3 subjective and objective working conditions of the interviewed professors regarding the Inclusion-Exclusion of Children with Special Teaching Needs in Early Childhood in the city of Sao Carlos. The answers provided by the professors seemed to indicate a resistance to such process motivated by the lack of required information and knowledge regarding the professional performance, a personal feeling in synchrony with social meaning of the teaching profession manifested in the interviews, and an urgent need to review the salary policy of education professionals.
Aluminato de lantânio puro e dopado: obtenção e caracterização elétrica
(Universidade Federal de São Carlos, 2009-02-20) Villas-Bôas, Lúcia Adriana; Souza, Dulcina Maria Pinatti Ferreira de; https://lattes.cnpq.br/4100119317525940; https://lattes.cnpq.br/5196590498448169
In the attempt to find new electrolyte materials for Solid Oxide Fuel Cells (SOFC) that works at low temperature, perovskite-type materials have been intensively investigated. These materials have favorable crystal structure for the creation of oxygen vacancies since a variety of elements can be accommodate in the crystal lattice. Among these materials stands out LaAlO3-based perovskite which, when adequately doped, presents considerable ionic conductivity. However, in spite of doped LaAlO3 presents high ionic conductivity, it also presents p-type electronic conductivity under oxidizing conditions, which would limit his use as electrolyte. In this work, powders of pure LaAlO3 and Sr, Ca and Ba-doped individually and, in the case of Sr, also Pr and Mn-co-doped, were prepared by oxide mixture through successive calcinations. Samples, obtained via isostatic pressing, were sintered at 1500 and 1600 °C in air during 6 h of soaking time. Sintered samples were characterized by X-ray diffraction, scanning electron microscopy and impedance spectroscopy. Among the different kind of dopants (Ca, Ba and Sr), the Sr-doped sample was that one which had the higher conductivity, both the grain (σgrain = 1,8x10-2 S/cm at 800 °C) and total (σtotal = 9,3x10-3 S/cm at 800 °C) conductivity. Sr- and Pr-doped samples presented higher ionic conductivity than Pr-undoped samples (σtotal = 2,3x10-2 S/cm at 800 °C). This increase was attributed to the highest oxygen vacancy mobility since the presence of Pr+3 in crystal lattice did not introduce additional oxygen vacancies. The Mn co-doping generated samples with high electronic conductivity. It was also observed that all of the samples presented two common features: the total conductivity is controlled by the grain boundary, i. e., the grain boundary is more resistive than the grain, and the microstructures are two-phase and the majority phase is dopant depend.
Secagem de sementes de Arachis hipogae L. com capa protetora
(Universidade Federal de São Carlos, 2009-02-20) Nascimento, Bruna de Souza; Sartori, Dermeval José Mazzini; https://lattes.cnpq.br/9084263442212447
Arachis hipogae L. peanut is an orthodox seed that must go through a drying process to become free from aflatoxin. The fruit is formed by a system made up by a nucleus and a resistant involucre that constitutes a heterogeneous mixture. So as to contribute to the improvement of those seeds drying, the objective of this study is to analyze the drying of the compound system and its subsystems in relation to moisture transport and shrinkage, as well as the influence on physiological and physical characteristics. In order to do so, the fruit, the seeds with and without endocarp, as well as the pericarp were placed in a forced convection dryer. To approach the problem, the idea of fluid flow on submerged bodies was adopted. The experiments were conducted based on a 32 experimental planning with temperatures of 30, 40 e 50°C and velocities of 0,5; 1,0 e 1,5 m/s. The intermittent method was used to measure the samples mass and to obtain the images. Analysis of the physical and physiological characteristics was performed from observations during the experiments. The results showed that the diffusive transport of moisture was predominant when the fruit and seed with and without the endocarp are concerned. The convective mechanism was also observed for the pericarp. As far as the physical barriers effect is concerned, it was verified that the pericarp and the endocarp cause resistance to mass transport. It was possible to verify the development of the seed s (with and without the endocarp) superficial concavity through image analyses with the aid of IMAGE PRO PLUS® software. However this deformation was not observed for the fruit or for the pericarp. The dimension reductions demonstrate the presence of the shrinkage phenomenon for the seed with and without the endocarp. The results regarding the physiological and physical characteristics showed dependency on operational conditions used when the seeds are processed outside the pericarp. Analysis concerning the process interaction with the product characteristics demonstrated that convective drying is a promising technique having a better relation between the process and quality for the product. Due to the results obtained, the discrimination of the equations that represent drying kinetics with focus on the improvement of seeds production was performed. The advancements obtained contribute to the drying studies of seeds that present protective cover under the perspective of seeds drying engineering.
Influência do ciclo menstrual na atividade eletromiográfica e na cinemática do joelho durante a aterrissagem do salto
(Universidade Federal de São Carlos, 2009-02-20) Cesar, Guilherme Manna; Serrão, Fábio Viadanna; https://lattes.cnpq.br/8137335642635433; https://lattes.cnpq.br/9023799568207801
Habilidades sociais educativas na interação professor-aluno
(Universidade Federal de São Carlos, 2009-02-20) Manolio, Carina Luiza; Del Prette, Almir; https://lattes.cnpq.br/2191226494887247; https://lattes.cnpq.br/8954629444758162
The interaction between students and teacher-student are considered a basic aspect of the education-learning process. The nature and the quality of this interaction will play a decisive role on this process s characteristics and on the products of the school. The present study intends to verify in a larger sample based on the System of Educative Social Skills, which classes and subclasses teachers have in the interactions with their students and demands observed; characterize possible patterns of behaviors teachers and check the influence of sociodemographic characteristics in issuing these standards and to analyze the frequency and the quality of teacher interaction and students with low academic performance and students with good academic performance. In this research, the sample was twenty teachers from Elementary School in interaction with its pupils. The pupils were selected by Protocol of teacher evaluation and formed a group with four learning difficult students and four good academic performance students. The correlational method was used to check the relations between variables. The study was conducted in classrooms of three basic education municipal schools of a town from São Paulo state. The instruments were: 1) Instrument of socioeconomic status evaluation ( Critério Brazil ); 2) a Protocol for teacher s characterization; 3) a Protocol of evaluation by the teacher and 4) Educative Social Skill s System (ESS). There was a pilot study to define aspects as adaptation time, demands to be made, the length of videotaping and the positioning of equipments in the classroom. Data collection was registered in thirds of 30 minutes each. The first part of time was adaptation and the other two were the videotaping of demands (Portuguese and Mathematic classes).The filming analysis was done through systematic observation and the frequencies was registered in a protocol based in ESCS. For reliability of observation data, three judges of prior knowledge of Social Skills were trained to analyze 20% of data collected. Descriptives and inferential analysis were used (Mann-Whitney test and ANOVA Kruskal-Wallis test). The results indicated: (a) the existence of a stable pattern, because the participants showed little flexibility and variability of behavior; (b) the influence of variables such as age, degree and range in issuing behavior considered ESS, (d) was not statistically significant difference between groups of students, but it was observed that the teachers the most positive responses from students with good academic performance of students. These results led to a characterization of the teachers repertoire and showed the need for implementation of programs of intervention in social skills for these teachers.
Efeitos do exercício resistido de membros superiores na força e na funcionalidade do paciente com DPOC
(Universidade Federal de São Carlos, 2009-02-20) Ike, Daniela; Jamami, Maurício; https://lattes.cnpq.br/4274129560250050; https://lattes.cnpq.br/0661715884992529
The aim of this study was assess the effect of the resistance exercise in upper limb on the strength and functionality in COPD patients moderate to very severe. Methods: Twelve patients with clinical diagnosis of COPD were distributed into 2 groups: control (GC) and trained (GT). During 6 weeks, with frequency of 3 times a week, the GT carried out strength training with load of 80% of one repetition maximum (1RM) and GC performed bronchial hygiene sessions and functional respiratory reeducation. Before and after the treatment were carried out the 1RM test and the Pegboard and Ring Test (PBRT) in both groups. Results: After treatment observed significant increase of the strength muscular only in GT (increase of 52% in the supine and 22% in the pulley), and in the PBRT there were not significant difference in the number of moved rings in both groups. Conclusion: The upper limb strength training during 6 weeks was be able to improve the upper limb muscle strength, but not the functionality of COPD, assessed by PBRT, in patients with COPD moderate to very severe.
Aplicações de resíduo de bauxita e cinza pesada da indústria do alumínio na fabricação de cimento Portland
(Universidade Federal de São Carlos, 2009-02-20) Montini, Marcelo; Rodrigues, José de Anchieta; https://lattes.cnpq.br/4000441989868775; https://lattes.cnpq.br/7001466550550811
Presently, a sustainable development is considered fundamental for the success and competitivity company s. Believing in such, the major Brazilian aluminum manufactures have invested, over the last two years, more than U$S 50 millions on programs focused at sustainability. With this in mind, the aluminum industry is not saving efforts to find applications ecologically and economically feasible for its main waste. Thus, the target of the present research work was to investigate the possibility of adding red mud (in natura and calcinated) and bottom ash, solid wastes resulting from the aluminum production on Portland cement, as pozzolanic additive to the cement. Additionally, was evaluated the use of red mud on the raw meal for the production of Portland cement clinker. In order to study the pozzolanic properties (according to NBR 5752/92 e NBR 5751/92) from these wastes, tests on determination of the pozzolanic activity were carried out and one further step were prepared Portland cement samples with 6%, 14%, 30% and 50% of residue. Besides that, clinkers Portland cement were produced with 5.9 and 12% by sintering the raw meals at 1450oC. The results of the pozzolanic activity and physical and mechanical essays (setting time, expansibility and compressive strength) showed the addition of up to 46% of bottom ash did not affect negatively the quality of the produced cement. However, the red mud couldn t be considered a pozzolanic material because it has presented pozzolanic activity below the demanded limits from the Brazilian Cement Standards. The clinkers produced with red mud presented chemical and mineralogical characteristics similar to the clinker from a cement plant industry. In addition, the mortar (clinker from red mud + gypsum) presented a good compressive strength after 7 and 28 days of curing.
Investigação do efeito de injeção de líquido por orifícios múltiplos na formação de gotas em um lavador Venturi
(Universidade Federal de São Carlos, 2009-02-20) Guerra, Vádila Giovana; Coury, José Renato; https://lattes.cnpq.br/0752059622240208
Venturi scrubbers are widely used in industrial plants in the cleaning of gases. In these scrubbers, the cleaning elements are the droplets formed at the injection of a liquid in the gas containing pollutants. The droplets act as collectors, incorporating the element to be removed. The liquid is usually injected through several orifices that promote a distribution of the droplets in the gas duct. The number of experimental studies in the formation of droplets in the Venturi scrubber is scarce, especially those concerned with the variation of the droplet size with the number of orifices of liquid injection. Therefore, the present work focused on the experimental investigation of the effects of the liquid injection in multiple jets in the formation and distribution of droplets in a Venturi scrubber. A laboratory scale scrubber, with a throat of 27 by 40 mm of cross-sectional, horizontally placed, was investigated. The data on droplet size was obtained with the Malvern Spraytec analyser, that makes possible in situ measurements by the passing a laser beam through the throat of the scrubber. The droplet size was analyzed varying the number of orifices of injection of the liquid from 1 to 4, the liquid flow rate between 300 and 1200 mL/min and the gas velocity in the throat of 59, 64, 69 and 74 m/s (L/G between 0.07 and 0.3 L/m3). The axial positions for measurements along the scrubber were varied between 120 and 240 mm. The effect of the formation of liquid film in scrubber walls was also analyzed. The experimental results showed that the increase of the liquid flow rate allowed a better distribution of the liquid inside the throat and also caused a stronger interaction among the jets. The number of injection orifices showed significant influence in the measured droplet size inside the throat, with the increase of the drop size with the increase of the number of orifices in operation. The interaction between jets and their droplets showed to have influence in the final size of the measured drop, since these sizes were larger in jets with larger interactions. The increases in the liquid jet and in the gas velocities favored the atomization process, causing decrease in the droplet sizes. The fraction of liquid film deposited in the walls of the scrubber varied significantly with the number of orifices in operation and consequently with the different penetrations of the jets. In general, jets with excessive penetrations generated a larger film fraction deposited in the walls of the scrubber and a smaller size of droplets. Through the analysis of dimensionless parameters, it was possible to quantify the influence of each operational condition in the size of the droplets generated inside of the studied Venturi scrubber.