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Avaliação da compatibilidade entre Y-TZP e BICUVOX para obtenção de compósitos condutores de íons de oxigênio
(Universidade Federal de São Carlos, 2013-09-27) Piva, Roger Honorato; Morelli, Márcio Raymundo; https://lattes.cnpq.br/0172837599844991; https://lattes.cnpq.br/0515321727144523
The BICUVOX is a potential candidate for devices that require materials with high ionic conductivity at intermediate temperatures. However, deficiencies such as low mechanical resistance and thermodynamic stability in reducing atmospheres have been introducing unsolved obstacles for technological appliance of this material. Unlike BICUVOX, the Y-TZP phase presents high mechanical resistance and high stability under reducing atmospheres. However, it does not display high ionic conductivity at intermediate temperatures. In this work we studied the compatibility between the BICUVOX and Y-TZP for the development of composites oxygen ion conductors. The composites were prepared by liquid phase and solid-state sintering. All characteristics were determined by XRD, SEM, DSC, diametral compression, impedance spectroscopy and treatments in H2 atmosphere. Using the BICUVOX as liquid phase additive, destabilization of tetragonal zirconia and formation of YVO4 take place. However, the solid state sintering enables the development of dense composite with up to 26% of Y-TZP. The composite with 26% of Y-TZP exhibited α = 10.10-6 ºC-1, which is a lower value than the one found for the BICUVOX, in addition to 144% higher mechanical resistance than for the BICUVOX. Also, for this composite a deleterious order-disorder transformation, γ ↔γ, was inhibited. All these improvements are attributed to the effect of Y-TZP both in the inhibition of grain growth, as well as in the preferential location among the grain boundaries of the BICUVOX matrix. However, the increase of grain boundaries and the Y-TZP as an additional phase, reduced the total electrical conductivity in composites. No resistance to γ-Bi4V1,8Cu0,2O10,7 phase decomposition was observed after exposure to H2. A general assessment indicates that the best properties are found in composite with 13 and 26% of Y-TZP, showing some improved properties in relation to each isolated materials.
Efeitos do treinamento de força no músculo esquelético de ratos jovens e senis
(Universidade Federal de São Carlos, 2013-09-27) Lopes, Giselle Nunes; Araújo, Heloísa Sobreiro Selistre de; https://lattes.cnpq.br/4065824911933203; https://lattes.cnpq.br/0104203971575071
Introduction: The skeletal muscle is the largest tissue present in vertebrates and is involved in locomotion, posture and breathing movements. It is composed of elongated, cylindrical and multinucleated muscle fibers with fat droplets in the sarcoplasma, known as intramyocellular lipid (IMCL) used as energy during exercise. Another source of energy used by the muscle is the carbohydrate stored in the body as glycogen, which is stored in the liver and muscle fibers. Muscle fibers are also surrounded by an extracellular matrix (ECM) formed, among other components, by collagen, mainly types I, III, IV and V. The aging process is associated with loss of muscle mass, muscle strength and function, increase of IMCL, reduction in glycogen synthesis with consequent insulin resistance, and also fibrosis and deposition of ECM. On the other hand, strength training (TF) is considered appropriate intervention to modify, minimize or reverse some physiological changes in skeletal muscle, as a result of aging. Thus, this study aimed to assess the cross section area of skeletal muscle fibers, amount of IMCL, glycogen content and MEC properties of the gastrocnemius (GAM) and soleus (SO) of young and senile rats after TF protocol. Methods: 28 rats were randomly divided into 4 groups: Youth (J); Old(S); Youth who underwent strength training (JT); Old who underwent strength training (ST). The animals performed strength training protocol consisting in climb a vertical ladder with weight strapped in their tails of 65%, 85%, 95% and 100% of the maximum load of the animal 3x a week for 12 weeks. CSA of muscle fibers, detection of collagen and identification of adipocytes in the GAM and SO muscles, beyond determinations of glycogen in the liver and skeletal muscle were performed. Results: Senile animals had lower CSA values, greater amount of IMCL, as well as of connective tissue in both muscles, but did not change the glycogen content in liver and muscle. After TF, the CSA increased in young and old animals in both muscles, the reduced IMCL in SO muscle of old animals, connective tissue decreased in young and old animals in both muscle and, finally, the glycogen content increased in liver and muscle of young and old animals. Conclusion: The strength training protocol in old rats was able to increase the CSA, decrease IMCL, increase of stored glycogen and decrease the connective tissue present in GAM and SO muscles. These results showed that there are changes in muscle fiber size, in the quantity of IMCL, in glycogen storage and in properties of the ECM of the GAM and SO muscle after intervention, indicating that strength training minimizes some deleterious effects inherent aging.
O ensino-aprendizagem de probabilidade em uma escola pública de Sorocaba/SP
(Universidade Federal de São Carlos, 2013-09-27) Canaveze, Leila; Oliveira, Paulo César; https://lattes.cnpq.br/7516513469811353; https://lattes.cnpq.br/0524706686441957
This qualitative work aims to describe and analyze a scenario of teachinglearning of the concept of Probability in three classes of the second grade of high school, a public school in the municipality of Sorocaba, State São Paulo. The look on this scenario of investigation was guided by the following research question: as occurs the teaching and learning in a context of tasks involving different probabilistic conceptions? For to answer this problem we developed a research field work where the researcher also played the role of teacher of such survey classes. With the help of the theory of semiotic representation records, analysis of the fieldwork revealed that the need to emphasize to students, through the application of tasks, the need for an adequate appropriation of terms pertinent to probabilistic language. The term that generated conflict in terms of meaning was the word luck. The option for minimizing the use of formulas has meant that students should use natural language and numerical registry as predominant forms of express written protocols of its activities. The use of products from records such as tree diagram and double-entry table had a supporting role in students ' writing process, getting restricted to set out the tasks explicitly demanded the student's activity using such forms of expression; or by the encouragement of a teacher-researcher. The educational intervention in support of the mobilization of different forms of semiotic registers, as the theoretical assumption of Raymond Duval, contributed to the learning of the concept of probability.
Planejamento da produção na indústria de embalagens em polpa moldada
(Universidade Federal de São Carlos, 2013-09-27) Martínez, Karim Yaneth Pérez; Toso, Eli Angela Vitor; https://lattes.cnpq.br/6014128945023344; Araujo, Silvio Alexandre de; http://lattes.cnpq.br/9919773182316062; Morabito Neto, Reinaldo; Alem Júnior, Douglas José; http://lattes.cnpq.br/0744448264150067
This research deals with the production planning and scheduling problem in the molded pulp packing industry, studying particularly a plant of molded pulp packages for eggs. The production process can be subdivided into two processes: molding process and printing process. The main challenge for production planning activities is on the molding process, where products are produced through tooling that have several molds. These tooling are called "Molding Patterns" or " Conformation Patterns". Each one of the molding patterns can contain one, two, until three kind of molds, allowing to produce several products simultaneously. Producing several products at the time can generate large inventory for low demand products and also null inventory for high demand products. Thus, different inventory levels are defined for each product based on their demand behavior, in order to control inventory quantities. In this way, decisions related to the production planning and scheduling in this production process involve deciding which molding patterns should used, how much time they should be used, and how they should be sequenced. All these should be make taking into account a parallel machine system and sequenced-dependent setups time and costs, in order to minimize inventory and setups costs, as well as penalties associated to inventory out of the specified inventory levels of each product. To represent this problem we proposed two formulations: the first one based on the Capacitated Lot Sizing and Scheduling Problem (CLSP), and the second one based on the General Lot Sizing and Scheduling Problem (GLSP). The results from the models were compared in a set of real word instances of a plant, in order to check the adequacy to represent the decisions involved in the studied production process, as well as the main differences between their production plans and performance of the models. The proposed formulations were also adapted for a particular instance, in order to compare their productions plans against the production plan implement by the studied plant. Results show that the proposed models represent rightly decisions involved in the production planning and scheduling in the molded pulp. Furthermore, the solutions obtained by the proposed models represent production plans with costs significantly lower than the schedule implemented by a real plant in this kind of industry.