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Esboço de uma rede de cooperação em um arranjo produtivo local na indústria calçadista paulista
(Universidade Federal de São Carlos, 2012-09-14) Queiroz, Timóteo Ramos; Côrtes, Mauro Rocha; https://lattes.cnpq.br/6281411676195221
Clusters of companies have been widely studied by gains from the actors that compose them. However, the strong bias for such studies still fall on the economic benefits and very little to address the attributes of social relationships that constitute, integrate and maintain such networks. So, we decided to studies and surveys of clusters, choosing to focus on Local Productive Arrangements (APLs), among the many possible configurations. In order to advance this work in this area has focused on design, characterize and analyze the networks of cooperation between industrial companies in a Local Productive Arrangement (APL) are the footwear of Sao Paulo. It then took the footwear cluster at Jaú, State of São Paulo. The method used for data collection was a questionnaire on the spot for the key players that made up the network and then sending structured questionnaires to companies. The data generated were converted into ordinal qualitative variables, so that it is possible to use the software UCINET version 6.283, to design and measurement network. The analysis provided an understanding and measurement of the relationship networks of enterprises and the network present in APL. It turned out that the social motives for cooperative action by the companies were classified as the same weight as economic reasons.
Desenvolvimento de borracha termoplástica por vulcanização dinâmica. TPV-(NBR+PP)
(Universidade Federal de São Carlos, 2012-09-14) Herrera, Julio César Alzate; Pessan, Luiz Antonio; https://lattes.cnpq.br/8276650236213537
The union of technology of thermoplastic and rubber has contributed to the development of thermoplastic elastomers (TPE), which was evidenced through the study of patents in TPE in the last 20 years, where Japan and the United States are the leaders. Trends in TPE are: modification to polymer structure in styrenic TPEs in order to employ the dynamic vulcanization, use of nanofibres and nanoclays, and resists oil TPEs using hydrogenated nitrile rubber to improve the properties of hot air and aging. The main variables in the development of TPE should take into account the surface energy the thermoplastic and elastomer, the elastomer entanglement, crystallinity of thermoplastic, proportions of the thermoplastic and compatibilizer. Typically the articles produced with nitrile, may be obtained using the technology or conventional rubbers (vulcanized), and not having possibility of recycling of defective products and materials vulcanizates. The purpose is to develop a thermoplastic nitrile rubber by dynamic vulcanization (TPV-(NBR + PP)) using conventional techniques for mixing between nitrile rubber and polypropylene. The development of nitrile rubber thermoplastic by dynamic vulcanization, TPV (NBR+PP) were studied with variation of vulcanization system, variation of proportion of NBR/PP and type of compatibilizer. The main results on development of TPV-(NBR+PP) were obtained with the use of system of vulcanization type phenolic resin, with compatibilizer Ph-PP and with 4,0phr of amine (6PPD). Developed a nitrile rubber thermoplastic by dynamic vulcanization (TPV-(NBR + PP)) with good performance in reprocessabilidade, using equipment and techniques conventional thermoplastic processing, which will help to satisfy the demands of industry.
Condutividade iônica e atividade termodinâmica em vidros x AgI (1-x) AgPO3, 0 ≤ x ≤ 0,5
(Universidade Federal de São Carlos, 2012-09-14) Bragatto, Caio Barca; Rodrigues, Ana Candida Martins; https://lattes.cnpq.br/4499231813051400; https://lattes.cnpq.br/5833076761496241
The ionic conductivity in solids is known since the 19th century, but the mechanisms of charge carriers transportation in amorphus solids is not yet fully known. The control of ths property is especially important for the development of fast ionic conductors (FICs) that can be applied in cell storage in electrochemical cells or in selective membranes. Through the dissolution of halogenate salts in a vitreous matrix, we can observe an increase of up to five orders of magnitude in the ionic conductivity of some glasses. To investigate this great variation of ionic conductivity, we propose a model based in the “weak electrolyte theory”. This theory, that says that the glass is a solution where the modifier (solute) is weakly dissociated in the vitreous matrix (solvent), was proposed in the 70’s to explain the non-linear increase of ionic conductivity in glasses with the increase of network modifiers (alkaline oxides). Were sintetized glasses from the family x AgI (1-x) AgPO3. The characterization showed interesting results, specially in the x ray diffraction, with the detection of a second amorfous halo for compositions with higher AgI content. Also, were realized impedance spectroscopy measurements, with a wide range of temperature, to determine the conductivity of the samples. To verify the proposed model, we proposed an experiment based in electrochemical cells, in wich we relate the electromotive force with chemical activity of AgI in the glass. We tested two methods to measure the activity of AgI: the first uses two batteries – one wich is a reference, using pure AgI, and the second with the glasses x AgI (1-x) AgPO3 . The second method is a concentration cell.
Síntese da zeólita Beta usando planejamento experimental e emprego na isomerização do n-hexano
(Universidade Federal de São Carlos, 2012-09-14) Oliveira, Kátia Dionísio de; Cardoso, Dilson; https://lattes.cnpq.br/2462847535959232; https://lattes.cnpq.br/6620016276509499
This work aimed to apply the Design Of Experiment (DOE) methodology as an auxiliary tool to evaluate the conditions of synthesis of the aluminum-rich zeolite Beta. Bimetallic catalysts with 50% platinum and 50% nickel (50Pt50Ni) supported on zeolites with various Si/Al ratios were synthesized, characterized and evaluated in the isomerization of n-hexane. In the first part of this work, five variables related to the synthesis of zeolite Beta were evaluated by a series of statistical designs, in which the response variables were the relative intensities of the X-ray patterns and the yield of phase BEA. The results of the t-test showed that the ratio TEAOH/SiO2 is not significant for the formation and crystallization of zeolite Beta. However, the interaction of this variable with the Si/Al ratio was statistically significant. In order to obtain the aluminum-rich zeolite Beta, the samples were synthesized with partial substitution of cations TEA+ by cations Na+. The XRD patterns of these samples showed that BEA phase was formed using a Si/Al ratio of 5,0 and 7.5. These low values of Si/Al ratio were confirmed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and energy-dispersive X-ray spectroscopy (EDS). Information about the main properties of the 50Pt50Ni catalysts such as activity, conversion and selectivity to di-branched isomers in the isomerization of n-hexane were obtained by performing catalytic tests. Concerning these properties, the catalysts supported on the synthesized zeolite Beta (Si/Al = 7.5) showed better catalytic performance compared with catalysts supported on commercial zeolite Beta (Si/Al = 9.0). Additionally to these tests, a study on the kinetics of reduction of ions Pt2+ and Ni2+ on these catalysts was conducted using X-ray absorption spectroscopy (XAS). The combination of XAS analysis and catalytic tests showed the importance of maintaining a bimetallic platinum and nickel system in order to obtain satisfactory performance of catalysts applied to the isomerization of n-hexane. The XAS results suggested that Pt2+ ions are reduced in lower temperatures compared to Ni2+ ions, and that the addition of platinum to the nickel-based samples promoted the reduction of Ni2+ ions. The catalytic results suggested that equilibrium between acid and metal sites exists during the isomerization of n-hexane. The understanding of this equilibrium is of major importance to increase the yield and selectivity to di-branched isomers.
Seções de choque da interação de elétrons de energias intermediárias com moléculas poliatômicas e constituintes do DNA
(Universidade Federal de São Carlos, 2012-09-14) Sugohara, Renato Takeshi; Iga, Ione; https://lattes.cnpq.br/8934634344275868; https://lattes.cnpq.br/8807948509480699
Elastic Differential Cross Sections (EDCS) were measured for the interaction of electrons in the incident energy range of 100-1000 eV, with several polyatomic molecules, namely: ethane (C2H6), propane (C3H8), methanol (CH3OH), ethanol (C2H5OH), sulfur dioxide (SO2), tetramethylsilane - TMS (C4H12Si), tetrahydrofuran - THF (C4H8O), trimethylphosphate - TMP (C3H9O4P) and ethyl acetate (C4H8O2). Crossed beam geometry is used and the intensities of elastically scattered electrons selected by a retarding field analyzer are measured as function of the scattering angles. The covered angular range is from 5to 130and the relative flow technique is used to normalize experimental scattered intensities to absolute scale. The secondary standards are Ar and N2. Only for TMP the normalization to absolute scale relied on theoretical values calculated with the Independent Atom Model (IAM). The EDCS curve was manually extrapolated to generate data in the forward and backward directions that were not covered experimentally. The full curve of EDCS from 0º to 180º was then integrated to give the Integral Elastic Cross Sections (IECS) and Momentum Transfer Cross Section (MTCS) in the 100 1000 eV interval. Part of results of this study has already appeared in scientific articles in the specialized literature. The results are new for TMP and ethyl acetate. The present experimental values of EDCS, IECS and MTCS are reported in comparison with available data. There was no experimental data in the literature to be compared with our measurements, in the 200 1000 eV except for THF. The theoretical data used for comparison are based on the Schwinger Variational Iterative Method (SVIM) and the Pade Approximant with the computer code EpolyScatD. In addition, the IAM and the Additivity Rule (AR) were also used to generate theoretical EDCS values. In general, a good agreement was seen between theoretical and experimental values. This study points out the importance of inclusion of the absorption effects in the optical potential, especially for intermediate energy electrons and scattering angles above 20º.
Indicadores de qualidade na Educação : um estudo a partir do PISA e da TALIS
(Universidade Federal de São Carlos, 2012-09-14) Corradini, Suely Nercessian; Tancredi, Regina Maria Simões Puccinelli; https://lattes.cnpq.br/1218621185470217
International Student Assessment) and the results presented by TALIS (Teaching and Learning International Survey), considering the configuration of schools highly evaluated and the practices developed in those institutions. Concerning that matter, two questions were designed as guidelines for the research process: (1) What is the configuration of the schools that performed well in PISA 2009, in São Paulo, according to the TALIS / PISA? (2) What kind of practices are developed in those schools? Considering those questions as a starting point, the procedures of one public and two private schools in the State of Sao Paulo were examined. Those institutions were chosen due to their good scores in PISA 2009. Matching the PISA 2009 modus operandi, the results obtained in reading were selected as the core of our analysis. Three specific objectives were established to shape the procedures followed in this research: (1) analyze the elements that influence the educational performance of students by focusing essentially on the features of their formation, (2) identify the characteristics of teachers and schools by assessing TALIS results, and (3) analyze the opinion of teachers and institution managers on PISA, TALIS and students performance. The current objectives are accomplished by adopting a quantitative-qualitative methodological research approach. The data consist of interviews with the general coordinator of PISA 2009 in Brazil and with directors / coordinators of the selected schools; visits to the focus schools; analysis of a collection of questions from PISA answered by students and directors and analysis of TALIS questionnaires answered by the director and teacher participants. This investigation is justified, therefore, by the potentiality it offers to the understanding of the contributions of PISA and TALIS results to the formulation of public policy and education management in Brazil and its implications for the educational system and schools. It was attainable by analyzing the organization of schools with good performance in PISA in Sao Paulo, considering such aspects as components of quality indicators. Within this context, the results of those large-scale measurement instruments raise important issues, since they acknowledge only a small number of "high quality schools" contrasted with a great number of units, especially public, marked by insufficient and below expectation performance. Further than analyzing the schools based on the results from PISA and TALIS, the outcome of this research invites for reflection on the practices adopted by schools and their relation to the results verified by the focused instruments.
Efeitos da alimentação/digestão e do jejum prolongado sobre a função cardíaca de cascavéis, Crotalus durissus terrificus
(Universidade Federal de São Carlos, 2012-09-14) Paula, Gabrielle Silveira de; Kalinin, Ana Lúcia; https://lattes.cnpq.br/5493936744279888
Some snakes have the ability to survive long periods without food and are capable to ingest large meal size. The ingestion of proportionally large preys triggers an expressive increase on the oxidative metabolic demand (SDA Specific Dinamic Action) which can become several times higher than the resting metabolic rate. The two described extreme situations might lead to cardiac changes to adapt structure and function in order to afford these two opposite physiological demands. During long food deprivation (Phase III), the depletion of the body structure may affect the heart muscle. That should be reverted to the SDA and prevent an overload on cardiovascular system. The standard cardiac function of South-american Rattlesnake, Crotalus durissus terrificus, was described as well as the changes caused by long term food deprivation and SDA. The importance of sodium-calcium exchanger (NCX), functionality of sarcoplasmic reticulum, extracellular calcium dependence and the effect of adrenergic stimulation were tested in adult animals at 30°C, under three different metabolic states: postabsorptive, SDA peak and food deprivation. The ventricular mass does not change after food deprivation and SDA. The force of contraction was higher in the base of the heart if compared to the apex, but there is no difference among the experimental groups and it is probably reflex of the fiber orientation in each region of the ventricle. The sarcoplasmatic reticulum is functional in all groups, but the dependence of reticular calcium is lower during starvation compared to the other groups. Muscle contraction is mostly supported by the extracellular Ca2+. The NCX have minor contribution to force generation (20%) but has a major role pumping calcium out of the cell (faster than SERCA). The increase in extracellular Ca2+ concentration during digestion can augment twitch force and would represent a contractile advantage to support the increased cardiac work without the development of hypertrophy. The adrenergic stimulation produced sustained increase in Fc for a wide range of stimulation frequencies in all the tested groups.