Browsing by Issue Date, starting with "2012-08-28"

Filter results by year or month

Now showing 1 - 20 of 18619

Programa de Aquisição de Alimentos (PAA) da agricultura familiar no município de São Carlos: impactos socioeconômicos nos agricultores familiares beneficiários
(Universidade Federal de São Carlos, 2012-08-28)
Rossi, Fabiana Ribeiro
;
Souza Filho, Hildo Meirelles de
;
https://lattes.cnpq.br/3203702000103304
The Food Acquisition Program from Family Farm (PAA) was created in 2003, within a group of policies with structural significance of the Zero Hunger Program, in order to promote actions in the scope of agricultural policies and food security. Its operation is made through modalities that purchase products from family farmers, without bidding. The PAA, since its institutionalization, has been the focus of several analyzes, as their impacts on the family farmers beneficiaries. This dissertation aimed to evaluate the impacts on family farmers beneficiaries of the Direct Purchase Local with Simultaneous Donation (CDLDS), executed since 2006, in the city of São Carlos, by the Municipal Agriculture and Food Supply (SMAA). The data collection was done by applying a structured questionnaire to a representative sample of 30 beneficiaries of the program in São Carlos and adjacent municipalities. The data were analyzed using descriptive statistics and hypothesis testing, which allowed the identification of positive impacts of the program in aspects related to their life conditions, land use, crop production, commercialization of products, agricultural income, association, family assets, investment properties, access to rural extension and information, agricultural practices, quality management, among others. No significant impacts were identified in aspects related to property management techniques and production, access to rural credit, participation of women, among others. The PAA can be considered an important program for family farmers beneficiaries because it is an alternative market channel to sale the production, collaborating, through its set of actions, with a more sustainable inclusion of its beneficiaries in other markets.
Reminiscência e dialética no diálogo Fedro de Platão
(Universidade Federal de São Carlos, 2012-08-28)
Müller, Nestor Reinoldo
;
Souza, Eliane Christina de
;
https://lattes.cnpq.br/5658382257368048
;
https://lattes.cnpq.br/7145572432457857
This dissertation aims to investigate, in Phaedrus text, the concepts of recollection and of dialectic, in order to explore some hypothesis of possible relation between them. The inquiry of the first concept is accomplished in the second section of the dialogue, where recollection reveals itself as an experience of access to the essential realities on the intelligible level. The research discriminates three aspects of recollection and seeks to analyze their implications to the main question represented by the connections between the sensible and the intelligible levels. The study of dialectic proceeds from de distinction among a wider and original sense of the word, denoting the conversation through questions and answers on any one subject, and the more precise and systematic sense developed by Plato, signifying the operation of synthesis and analysis. The research examines the entire dialog but privileges the six descriptions of dialectical technical procedures that can be found in the third section, presented as a new method to a real rhetorical art. Giving attention to some signs of approximation and some fields of convergence between recollection and dialectic, the dissertation raises four hypothesis aiming at possible intersections between the two concepts.
A função social e a refuncionalização do território ferroviário da Cia Mogiana em Ribeirão Preto
(Universidade Federal de São Carlos, 2012-08-28)
Zamboni, Débora Prado
;
Falcoski, Luiz Antonio Nigro
;
https://lattes.cnpq.br/3200660670856698
;
https://lattes.cnpq.br/5585378083851286
This paper investigates the relationship between the railroad present in Ribeirão Preto and urban organization of this township. Its principle the importance of the use of public assets in minimizing social inequalities from the use of part of the heritage of the Brazilian railway network, the non-operating properties, present in Ribeirão Preto in the perspective that all property should fulfill its function given the social regulation of urban policy in Brazil. Contrary to this end it is important the historical fact of the heritage railway in Ribeirão Preto have been mainly used for the consolidation of routes in the city, urban decision that gives value to certain areas of the municipality. This paper investigates the enhancement of areas of the county through the use of rail assets, whether public or private. Finally, it appears as if nowadays gives the relationship between the urban municipal legislation and the use of what is now public property rail in reducing social inequalities. As a goal, it is expected to act positively on the stage of understanding and minimizing social differences in urban space.
A aprendizagem cooperativa nas aulas de matemática : uma experiência nas turmas de 8º e 9º anos
(Universidade Federal de São Carlos, 2012-08-28)
Gouvêa, Mariangela Salviato Balbão
;
Sampaio, João Carlos Vieira
;
https://lattes.cnpq.br/8286887389013685
;
https://lattes.cnpq.br/6105754049240250
The objective of this study is to establish whether mathematical activities, prepared based on cooperative learning, produce changes in how students learn and confront with mathematics. Thus, were designed, developed and analyzed six math classes cooperatives, which occurred in an 8 and a 9 th grade of elementary education at a private school. The proposed group of activities consists of mathematical problems written in the form of clue cards. Each group receives an envelope containing six cards, which must be distributed among team members. To solve the problem all students must contribute explaining their clues and sharing ideas. The teacher provides various materials to support the activities such as ruler, squares, compasses, paper, scissors, calculators, colored cubes, dice, straws, beans, charts etc. The results obtained by each group are described in the answer sheets, previously prepared by the teacher. Before and after cooperative classes, a questionnaire was applied in order to know the opinion of students about group work and their skills in mathematics. The results achieved with the cooperative activities were fruitful discussions on mathematical concepts and their properties, greater clarity from teachers regarding students' mathematical difficulties, greater social involvement, respect for ideas and opinions of group members, ability to represent mathematical situations by using concrete materials, drawings, graphics and text.
Uma ontologia evolucionista: considerações sobre a noção de "desenvolvimento" na obra de Darcy Ribeiro
(Universidade Federal de São Carlos, 2012-08-28)
Moreira, João Paulo Aprígio
;
Lanna, Marcos Pazzanese Duarte
;
https://lattes.cnpq.br/8355559441138016
;
https://lattes.cnpq.br/5542752158910620
This work investigates possible relations between a modern anthropological theory and discourses about "development". These relations are presented in theories of cultural change which will be consider with focus on the role mediators play in the production of specific meanings to the notion of "development". The analysis focus on Darcy Ribeiro´s 'The Civilizing Process: stages of sociocultural evolution', published in 1968. In thhis book Ribeiro presents his theory articulating a neoevolucionist anthropological perspective with a project of development for the Brazilian nation based on the concept of "technological revolutions". This concept is one of the foundations of Ribeiro's idea of cultural change at the same time offers a critique of dependency theory in Latin America, in the form of placing in th epolitical field debates on the underdevelopment-"Development" constrast. From the concept of technological revolutions, Ribeiro returns to the issue of cultural dynamics, dear to the theories of modern anthropology and grounded in an evolutionary perspective, as well as to the values of the national-developmentalism defended by Labour politicians - values that reside in the critical dependence of Latin countries' economic and the search for political autonomy, as well as in the defense of nations "underdeveloped" as the path to development.
A política de governo eletrônico no Brasil: uma análise dos governos FHC e Lula
(Universidade Federal de São Carlos, 2012-08-28)
Mantovane, Solange Aparecida
;
Capella, Ana Cláudia Niedhardt
This dissertation is proposing to make an analysis on how Information Technology and Communications became part of the structure of state administration in Brazil, taking into account their different stages of merger and consolidation in the context of the restructuring of the state late twentieth century. Specifically, it is to examine how the use of Information Communication Technologies was incorporated into the routine of public administration and translated into the creation and development of a policy for electronic government (or e- Government) in the period extending from first mandate of Fernando Henrique Cardoso to the last term of the government of Luis Inacio Lula da Silva. This analysis is done through a historical reconstruction of what has to be such a policy, covering all phases of development, beyond the key actors for implementation. We assume that the analysis of influence of theses mechanisms is fundamental to understanding the path that takes politics in this country. From this we make a balance between the two government studied in order to check the continuities, innovations and setbacks of e-government policy in the period. This balance is organized from the checklist used by Chahin (2004), is based on best global practices of e-government, and includes the following dimensions: leadership and coordination, policy formulation and evaluation, cultural environment, infrastructure and standards.
Efeito da imunização com enzimas recombinantes do metabolismo de nucleotídeos de Schistosoma mansoni sobre o desenvolvimento da esquistossomose mansônica experimental
(Universidade Federal de São Carlos, 2012-08-29)
Neris, Débora Meira
;
Anibal, Fernanda de Freitas
;
https://lattes.cnpq.br/4918261968772806
;
https://lattes.cnpq.br/8420021026488937
Schistosimiasis mansoni is a neglected chronic parasitic disease that affects thousands of people worldwide, caused by the trematode Schistosoma mansoni. In the infected host the disease is characterized by the presence of granuloma, imunnopathological response of the cellular infiltration against egg antigens. Thus, the host-parasite relation favors hepatosplenomegaly, acite and hepatic fibrosis. Current chemotherapy is based on the use of Praziquantel (PZQ), used against all species of Schistosoma spp for over 30 years. The main issue is that the PZQ is practically inactive against immature schistosomula and favors the resistance growth of the existent lineages, which makes the study for new drugs and vaccines that can contribute to the control of this disease even more urgent. One of the paths on the search for new therapeutic targets is the study of essential enzymes to the S. mansoni. In particular, it is known that the enzymes Adenylate Kinase 1 and 2 (ADK), Uridine cytidine Kinase 1 and 2 (UCK), Hypoxanthine guanine phosphoribosyltransferase (HGPRT) e Purine nucleoside phosphorilase 1 (PNP) are found on the metabolic pathways of the parasite s nucleotide, participating in the metabolism of purines and pyrimidines. Our goals in this study were to assess the immunization with these enzymes, using the S. mansoni cercariae infected murine model, and subsequently analyze the acting in oviposition and growth of adult worms. Our results showed that the immunization in Balb/c mice with the UCK enzyme was capable of inducing a specific immune response, which favored a significant reduction of the parasitic load (adult worms). However, it was not possible to observe significant reduction in the number of eliminated eggs. Regarding the immunization with PNP and HGPRT enzymes, the mice had a reduction in the number of eggs per gram of feces. The data obtained are considered interesting and can be new targets for immunotherapy against schistosomiasis mansoni. Thereby, new assays must be made with different dosages of the enzymes for a better assessment on how these enzymes modulate the parasitic load through the eggs reduction, reduction in the adult worms retrieving, as well as the antibody levels during the murine infection by the S.mansoni.
Internacionalização e mudança na gestão: um estudo de caso na indústria de eletrodomésticos de linha branca
(Universidade Federal de São Carlos, 2012-08-29)
Milaneze, Kleber Luiz Nardoto
;
Rachid, Alessandra
;
https://lattes.cnpq.br/6981682198988902
;
https://lattes.cnpq.br/1273696629694839
The purpose of this study is to analyze the process of ownership change in an appliance company, checking the impacts brought by this process in its management. For this study, it was performed a case study, during which were conducted interviews with managers from different areas of the company. It was also based on a literature in academic journals, economic analysis and sector and public agencies publications on the process of internationalization, the Brazilian economic indicators, and the appliance industry. The 1990s was a period remarkable for the internationalization of the economy, with the rise in trade, finance and information between countries. Brazil was integrated through this process by the trade liberalization for imports, which, together with the macroeconomic and political stability, have made the country more attractive for foreign investment. This context coincided with a period of an overvalued exchange rate, which, together with high domestic interest rates, led to the acquisition of national capital companies in various industries, including appliance industry. Since then, this industry has become an oligopoly, dominated by a few large multinational companies with significant consequences for the management of companies in Brazil. In the studied company, there have been significant changes in the management staff, in the organizational structure, as well as its strategic position, with implications for the operations and human resources management.
Estudo de mise-en-bande : a dinâmica do som em Last Days, de Gus Van Sant
(Universidade Federal de São Carlos, 2012-08-29)
Silveira, Juliana Panini
;
Miranda, Suzana Reck
;
https://lattes.cnpq.br/8566012598222563
This research is an analysis of Gus Van Sant s Last Days (2005) soundtrack. From the concept of mis-en-bande, that emphasizes the interactions between the different sounds of the film narrative, we propose to consider the details of the Last Days s sound organization and its crucial contribution to the proposed narrative discourse.
A morte de Vladimir Herzog e a luta contra a ditadura: a desconstrução do suicídio
(Universidade Federal de São Carlos, 2012-08-29)
Kleinas, Alberto
;
Grün, Roberto
;
https://lattes.cnpq.br/6028266827740491
;
https://lattes.cnpq.br/7899663984177059
The case Herzog had a strong impact on the recent political history of Brazil. A journalist killed on the premises of the 2nd. Army, in Sao Paulo, which was imposed by the establishment of suicide. Suicide wrought was challenged by his peers journalists, the Journalists' Union, the Archdiocese of St. Paul and in view of the pressures, the Jewish community of Sao Paulo. His burial was in an appropriate place for those who attempted against his life, and this burial and then act on Ecumenical Cathedral, are objects of this dissertation which seeks to clarify the reasons for this fact. As a Jewish collectivity could break with the collaboration and submission to the military regime, common in immigrant communities, and attest to the murder through the burial site of Vladimir Herzog. The contradictions and institutional pressures of Sao Paulo Jewish community demonstrate how external influence, Brazilian society was important in this episode, without underestimating the importance of individual people who were exposed to the truth and the struggle for democracy and human rights.
Tendências das perspectivas Ciência, Tecnologia e Sociedade (CTS) nas áreas de educação e ensino de ciências: uma análise a partir de teses e dissertações brasileiras e portuguesas
(Universidade Federal de São Carlos, 2012-08-29)
Miranda, Elisangela Matias
;
Freitas, Denise de
;
https://lattes.cnpq.br/3330976062026878
;
https://lattes.cnpq.br/2093003152737149
Nowadays, Science and Technology developments and influences on humanistic, social, cultural and economic dimensions have raised discussions about the nature, potential and limits of those areas. Science teaching according to STS (Science-Technology-Society) education comes out as an approach that aims to integrate scientific, technological and social themes in a given content. This approach stimulates students to develop skills that enhance their ability to play their role in society in an active and mindful manner, and hence contributes to the rise of a larger number of scientifically and technologically literate citizens. In that regard, the main objective of the present study is to analyze academic studies master s and doctoral theses produced between 1992 and 2009 that have focused on the STS education field, seeking to identify STS education perspectives pointed out in those studies during that time span. The secondary objectives of this study are: (i) to identify master s and doctoral theses in Education, Science and Mathematics Teaching or related graduate programs of Brazilian and Portuguese federal or state universities, all of the works dating from 1992 to 2009 and investigating approaches related to STS education; and (ii) to characterize the thematic focuses, methodological and STS approaches in those theses. Therefore, this is a state of knowledge research conducted according to a theoretical, bibliographical, and quantitative-qualitative approach, for which the Qualitative Content Analysis method was used. Among the most relevant results, it has been found that 14% of the investigated Brazilian theses were directed towards the college level, whereas none of the Portuguese theses had the same intent. On the other hand, 79% of the Portuguese theses were aimed to the first years of school, whereas only 21% of the Brazilian theses were devoted to that education level. Analyses were also carried out in order to identify and discuss which STS approaches and/or perspectives are present in doctoral theses finished at both Brazilian and Portuguese universities. Such analyses have indicated that the main STS education model observed in the theses is Logical reasoning (40% of the theses, i.e., 10 out of 24 theses), followed by Sociocultural (39% of the theses, i.e., 9 out of 24 theses), Historical (3 theses), Socio-ecojustice (2 theses), and Application/Design (1 thesis). In general, the analyzes revealed that, even though there is a consensus among the academic community involved with studies on STS education, different interpretations of STS-based Science education have been emerging along decades, which reveals a field under construction and reconstruction.
Banco de dados georreferenciado para apoio à gestão de trânsito em cidades de pequeno e médio portes
(Universidade Federal de São Carlos, 2012-08-29)
Vendrametto, Larissa Lenharo
;
Raia Junior, Archimedes Azevedo
;
https://lattes.cnpq.br/6413793013018019
;
https://lattes.cnpq.br/2276864795974596
The modernization of the cities has brought an improvement in the lives of the urban population, although the negative consequences weigh considerably. In any kind of transformation, the negative effects are not always considered and treated to abolish them or less minimize them. Traffic is a clear example of this fact. The significant increase in the fleet of vehicles has generated several urban problems such as high rates of occurrence and severity of traffic accidents, congestion and degradation of the urban environment, influencing the quality of life. With the enactment of the Brazilian Traffic Code (CTB) in 1988, municipalities assumed the responsibility to manage their traffic, adding to his responsibilities the authority to act in this area taking into account the interests and local peculiarities. In this sense, each municipality must municipalise directly assuming the powers specified in Article 24 of the CTB. However, municipalities have been reluctant to take charge of decentralization of traffic. According to data DENATRAN (2012), only 1,221 municipalities have effectively assumed the management of their traffic, which corresponds to 29% of 5,563 Brazilian municipalities. Many factors can be pointed as responsible for this reluctance, and one of them is the lack of knowledge of the reality of local traffic. It is important that the institutions, who are competent to intervene on the county road system and its maintenance, to know the dynamics of the space on which they intend to launch campaigns, a quality management includes the selection, acquisition, integration and use of information so systematized. The management and analysis of information associated with meaningful comparisons must adequately support the decision making process within the organization. Given this, the Geographic Information Systems - GIS become an effective tool and capable of helping the management, providing a modern and agile tool for specialized studies, with the recognition of the traffic situation as a whole. Therefore, this paper aims to contribute to the management of municipal public transit in cities small and medium-sized Brazilian, through the development of a tutorial to support the implementation of a geographic information system free - Free GIS, showing that it is not always necessary high investment amount for the production of quality information for management of a city road.
Simulação computacional, projeto, construção e análise do desempenho de uma matriz para extrusão em canal angular dedicada ao processamento de chapas
(Universidade Federal de São Carlos, 2012-08-29)
Springer, Phillip
;
Ferrante, Maurizio
;
https://lattes.cnpq.br/6067173982945625
;
https://lattes.cnpq.br/2504572620929191
The present work describes the design, construction and testing of an equal channel angular pressing (ECAP) die characterized by rectangular cross section channels. The main parameter of the ECAP dies is the geometry of the channels, given by the angle trough which they meet, and the curvature radii at this point. The material employed in the experiments was an Al AA1050, 7 mm thick plate. The main motivation of the project is to produce the tooling necessary for the production of samples to be employed in future studies, directed to the crystallographic texture change of the above named material so as to improve its deep drawing behavior. Indeed, there are indications that both asymmetrical rolling and ECAP processing can minimize unfavorable textures. This present investigation is composed by two sequential and complementary subprojects: (i) Numerical analysis by finite elements (FEM) of the simultaneous and independent variation of the external (R) and internal (r) curvature radii at the channels intersection, plus experimental validation, a procedure that seeks to minimize the deformation heterogeneity of the billet. Using a Pb-62% alloy twelve R-r combinations were tested and simulated, keeping constant the angle at the channels intersection. Also, the phenomenon known as "corner gap" (a detachment of the billet from the outer channel wall) was analyzed and its influence on the billet equivalent deformation determined. (ii) From the results obtained on subproject (i), and additional considerations, an ECAP die for flat billet processing was designed and constructed HAVING R =3 AND r = 0. Using FEM simulation the equivalent strain distribution was mapped for plates subjected to one and four passes. Experimental validation of such maps was carried out employing Vickers microhardness measurements of the viii plate cross section. The evolution of the tensile properties and grain size confirmed the good performance of the ECAP die design.
Simulação de um alimentador Venturi em trecho ascendente no transporte pneumático de sólidos
(Universidade Federal de São Carlos, 2012-08-30)
Padua, Thiago Faggion de
;
Freire, José Teixeira
;
https://lattes.cnpq.br/2270677706718167
;
https://lattes.cnpq.br/8909812973749651
The radial and axial distributions of coarse solids when fed directly in a riser are unknown, despite this type of feeding is very important for drying and preheating of solids during conveying. In this context, this thesis focused on studying the diluted conveying of coarse solids in a riser that was fed by a Venturi feeder in vertical orientation. Experiments were done with particles of 1mm averaged diameter conveyed in a riser (5.32cm of diameter) to obtain the mass loading ratio used in simulations. The assays also made pressure data available to verify the simulations. Eulerian simulations using models based on kinetic granular theory were done. The main goal was to evaluate solids distribution in gas-solid flow for this type of system. The 2D simulations were used to get a stable pattern downstream the feeder after the development length. However, the solid feeding structures generated near feeding percolated the entire riser and, as a consequence, there was no stable pattern. As a consequence, no pattern was found to represent solid phase behavior, since the axial symmetric assumption is invalid for the Venturi feeder. Therefore, only 3D simulations can be used to study asymmetric feeding for the conditions applied, even for a relatively long riser with small diameter. Experimental pressure data was approximately predicted by 3D simulations and prediction was better as the mesh was refined. However, the refined meshes applied in shorter risers to decrease computational effort showed the same solid flow behavior that was seen in the coarser mesh. The 3D simulations showed that there were clusters in the entire experimental riser. Moreover, clusters were generated by solid phase flow near feeding and some of them percolated the entire riser while mixing others. In addition, simulations showed that the bypass region on feeding is in the opposite side from feeding pipe.
Inserção, atuação e ascensão profissional: o papel do capital social em usinas sucroalcooleiras do interior paulista
(Universidade Federal de São Carlos, 2012-08-30)
Zanarotti, Vanessa Regina Cenedezi
;
Donadone, Julio César
;
https://lattes.cnpq.br/7643906508178259
;
https://lattes.cnpq.br/2862944241973678
From the financial logic that changes the investment outlook favoring capital dispersion and fragmentation of control of the business, many industries and businesses have been directly affected by the entry of new capital. In several cases the entry of new capital is not restricted to purely investment of resources, but influence the management of companies, for example, prioritizing the adoption of Corporate Governance as a necessary instrument to regulate the relations among more actors. As a result of these new practices, values, structures and culture are modified starting to integrate new models of standardization of organizational action. Through research conducted in the field in two sugarcane industries, one of family fully control and another of mixed control, aimed from the analysis of the results pertaining to two specific organizational actions: professionalization and dispersion of capital verify the value of the Social Capital in organizational environments surveyed focusing on the importance of this concept in the processes of insertion, performance and career advancement. In the surveyed companies, strong correlations were observed between new organizational processes and revaluation of Social Capital contradicting the initial expectations that the professionalization and dispersion of capital could undermine its importance. Moreover, the concept also showed his productive character in relation to the processes of insertion, performance and career advancement valuing the importance of it in the sugar and alcohol sector. Although the Social Capital is present in both surveyed professional environments, is apprehended differently in the two companies.
Preparação de catalisadores Fe/FER e Fe2O3/FER: avaliação na redução de NO com CO
(Universidade Federal de São Carlos, 2012-08-30)
Soares, Magmir Metzker
;
Urquieta-González, Ernesto Antonio
;
https://lattes.cnpq.br/3201421189723555
;
http://lattes.cnpq.br/2389975677904655
Due to the development of society, industrial processes and transportation (cars, buses, trucks, etc.) that emit pollutants are used, which affect the environment and consequently human health, flora and fauna. Among these contaminants, air pollution is the most complex, since it is becoming increasingly difficult to control, despite the efforts of more restrictive laws and the growing number of agencies for its regulation. Among the most worrisome issues stand out nitrogen oxides (NOx) generated throughout the combustion process of hydrocarbons. In the abatement of NOx, various catalytic processes are applied today. However, there is a need for them to be improved and upgraded, as to increase the activity and selectivity of the catalysts used for the conversion of NOx to N2. Thus, the air quality is preserved and the impacts of these contaminants in the environment are minimized. In this context, and considering the recent results in the literature and the Group of Catalysis UFSCar, this study aimed the preparation of catalysts based on cations Fen+ exchanged in zeolite ferrierite (|Nax| [SiyAlwOz]) or based on iron oxide supported and evaluated in the same reduction of NO to N2 by using CO as reducing agent. For purposes of comparison, catalysts were prepared based on commercial zeolites USY-type and mordenite under the same conditions of impregnation. Were also verified the effect of activity in the presence of O2, H2O(v) or SO2. The research included: i) preparation of ferrierite zeolite by ion exchange and impregnation of Mordenite and USY zeolite, ii) characterization via energy dispersive spectrometry of X-rays, atomic absorption spectroscopy, X-ray diffraction, scanning electron microscopy , diffuse reflectance spectroscopy in the ultraviolet visible reduction with H2 temperature-programmed and Mössbauer spectroscopy, iii) evaluating the reduction of NO with CO; iv) evaluation of the catalytic performance fronts interfering O2, H2O(v) and SO2. The catalytic tests showed that the samples with iron content close to 9% (FERtroca80 and FERimpr10) were the most active in the reduction of NO by using CO as reducing agent. The reaction was selective to the formation of desired products, even for high temperatures. The tests indicated that the sample interfering FERimpr10, which was more active in reducing the catalytic activity was not affected by the presence of SO2 or O2, being affected by the presence of O2 and H2O, which promoted a competition for active sites of the catalyst.
Desempenho de filmes soprados multicamada de blendas de polipropileno e copolímeros de etileno
(Universidade Federal de São Carlos, 2012-08-30)
Elias, Marcelo Brasil
;
Canevarolo Júnior, Sebastião Vicente
;
https://lattes.cnpq.br/4153664441338178
Polypropylene (PP) and polyethylene (PE) are widely used in the flexible packaging market individually as mono or multilayer films. Blending PP and PE in coextruded films has shown limited commercial applications due to the poor adhesion. On this work we made three layer coextruded blown films with ascendant flow and air cooling. The thicknesses were kept constant at 50m, having the external layers made of metallocene ethylene-octene copolymers (m-PE) to provide sealability. The internal layer (structural) was produced with rich blends of polypropylene homopolymer and ethylene-octene copolymers made by metallocene (m-PE and POP) and by Ziegler-Natta (U-PE) catalytic systems. These films were characterized by their mechanical, thermal, optical and morphological properties. Based on the results it is proposed a morphological model of the core layer, in which the matrix phase of PP has a shish kebab crystalline structure, and the disperse phase and the external layers composed by fragmented lamellar crystallites blended with small spherulites. The epitaxial crystallization of the polyethylene copolymer on the shishes of the polypropylene allows good adhesion between the external and internal layers of the multilayered structure. The internal structure formed with the dispersed phase of m-PE and U-PE has shown similar mechanical behavior with better properties at the concentration of 30%.On the other hand, when the dispersed phase of the internal layer is POP elastomer, the Tg and Tm of the matrix PP decrease due the compatibility between the matrix and the dispersed phase, generating shish kebab structures with lower crystallinity. These morphological characteristics guarantee a balanced film regarding the thermomechanical properties, in order to achieve a high performance flexible packaging.
Síntese, sinterização em forno de micro-ondas e caracterização da Fe-Ni, PZT e do sistema multifuncional magnetoelétrico PZT/Fe-Ni
(Universidade Federal de São Carlos, 2012-08-30)
Muñoz Hoyos, José Rodrigo
;
Kiminami, Ruth Herta Goldschmidt Aliaga
;
https://lattes.cnpq.br/7643216999108223
;
https://lattes.cnpq.br/4742056034033702
The production of multifunctional magnetoelectric materials today is potentiated in the manufacture of particulate (0-3 connectivity) or multilayer (2-2 connectivity) composites comprising a phase with magnetic properties and another with piezoelectric properties. The magnetoelectric response of this type of material depends on factors such as the properties of each of the phases in the composite, the microstructure and the homogeneity of the mixture of phases. The topic of this dissertation is a study of powder synthesis by the Pechini method and of the microwave sintering of ceramic bodies made of magnetic materials such as nickel ferrite and ferroelectric materials such as lead zirconate titanate, as well as an evaluation of their ferromagnetic and ferroelectric properties. This study includes an evaluation of the influence of microwave sintering on the microstructural, ferroelectric and magnetoelectric properties of particulate composites of the PZT/Fe-Ni (80/20) system. To this end, the powders were synthesized by the Pechini method in solutions at different levels of pH in order to evaluate the effect of this parameter on their particle size. The structural and microestructural characterization indicated that crystalline powders of both PZT and Fe-Ni phases were obtained, with nanometric particle sizes which decreased as the pH of synthesis increased. Dense Fe-Ni, PZT and PZT/Fe-Ni ceramic bodies were obtained by microwave and conventional sintering and analyzed by XRD, SEM and EDS. Fe-Ni and PZT samples showing high phase density and integrity were characterized by magnetic and electric hysteresis cycles, which elicited the typical responses of ferroelectric and ferromagnetic materials. The magnetoelectric coupling coefficient of samples of PZT/Fe-Ni composites with densities of >90 % and adequate phase integrity showed a value of 0.7 mV/cmOe for the microwave sintered sample and of 2.2 mV/cmOe for the conventionally sintered sample.
Distribuição e orientação dos quimiorreceptores de O2 branquiais em tilápia-do-Nilo (Oreochromis niloticus): controle das respostas cardiorrespiratórias à hipóxia
(Universidade Federal de São Carlos, 2012-08-31)
Zeraik, Vivian Maria
;
Rantin, Francisco Tadeu
;
https://lattes.cnpq.br/3546242299713690
;
https://lattes.cnpq.br/8434310797992303
In fish the O2 chemoreceptors are mainly found in the gill arches and monitor the O2 tensions (PO2) of the inspired water (externally oriented) and/or the arterial blood (internally oriented). During hypoxia these receptors trigger cardiorespiratory adjustments in order to maintain an adequate O2 transfer to the tissues. The aim of the present study was to determine the O2 chemoreceptors distribution through the gill arches of Nile tilapia and the role of these receptors on the cardiorespiratory responses to hypoxia in this species. One buccal and two opercular canullae, and a pair of ECG electrodes were implanted in a group of intact fish (control group, n = 10; Wt = 258.4 ± 7.4 g). This procedure served to measure the following cardiorespiratory variables: respiratory frequency - fR, ventilatory tidal volume - VT, gill ventilation - VG , O2 extraction from the ventilatory current EO2, oxygen uptake - VO2 , and heart rate fH. After an overnight recovery period from surgery fish were subjected to the following O2 tensions during 40 min each: 140 (normoxia), 100, 70, 50, 30 e 20 mmHg. To verify the O2 receptors distribution in the gills, the first pair of gill arches was surgically extirpated (operated group, n = 10; Wt = 232.5 ± 8.8 g). After a recovery period of 4 days, operated fish were subjected to the same procedures described above for the intact ones. To examine the orientation of these receptors, other intact (n = 10; Wt = 259.6 ± 6.2 g) and operated (n = 10; Wt = 248.7 ± 6.5 g) groups had a PE catheter implanted into the buccal cavity, another catheter implanted inside the caudal vein and fitted with ECG electrodes to measure the following variables: ventilatory amplitude (Vamp), fR, and fH. Two internal injections (administered through the cannula into the caudal vein): a) 0.5 mL intravenous saline (0.9%), b) 0.5 mL intravenous NaCN (750 μg.mL-1 of NaCN in saline) and two external injections (injected by oral cannula): c) 1 mL H2O, d) 1 mL NaCN (750 μg.mL-1 of NaCN in water) were administered in both groups. The VO2 of operated fish was significantly lower only in severe hypoxia. Both bradycardia, and respiratory parameters were not abolished by ablation of the first pair of gill arches. EO2 of operated group remained about 18% lower than that of control group. The responses to internal and external NaCN included decreases in fH and increases in fR and Vamp. The cardiorespiratory parameters were attenuated in the operated group, indicating the presence of chemoreceptors, but not limited to the first gill arch. In Nile tilapia the O2 chemoreceptors are distributed beyond the first gill arch, probably through the four gill arches. Furthermore, these receptors are internally and externally oriented, possibly along all gill arches, triggering the cardiorespiratory adjustments necessary to face the hypoxic conditions at which the species is frequently subjected in its natural environmental conditions.
Obtenção de inseticida e fungicida contra formigas cortadeiras e seu fungo simbionte em Myracrodruon urundeuva e de complexos de coordenação com metais de compostos ativos para controle desta praga
(Universidade Federal de São Carlos, 2012-08-31)
Sarria, André Lúcio Franceschini
;
Fernandes, João Batista
;
https://lattes.cnpq.br/2691336077459602
;
https://lattes.cnpq.br/9263468171419159
Insects are the major competitors for food in relation to humans. Ants ("sauvas" and "quenquéns") are the major pests of several culture and in reforestation areas in Brazil represent more than 75% of the time and financial expenditure in the control of forest pests and obviously limit the full development of agriculture and forestry. The technology involved in the search for pesticides for the control of pests is in the frontiers of science, which involves different aspects of multidisciplinary and can contribute greatly to the agriculture advancement. One of these aspects is related to natural products, where new molecules isolated from plants can serve as prototypes for new insecticides. The aim of this study was the phytochemical study of Myracrodruon urundeuva in order to search for compounds with insecticidal activity and the synthesis of metal complexes of copper with molecules that present biological activity. The phytochemical study led to the isolation and structural identification/caracterization of 34 secondary metabolites, being seven unique and among them, are the dimeric chalcones, only identified in two species of Anacardiaceae. 31 compounds were synthesized: eight of them have the ligands obtained by Mannich reaction with 2-hydroxy-1,4-naphthoquinone; eight complexes from these ligands; two iminic derived from the flavonoid naringine and naringenine; two complex from these ligands; four complexes of the type Cu(FLAV)2 and seven complexes of the type Cu(X)(FLAV) where X is 2,2´-Bipyridine our 1,10´- Phenanthroline. The extracts of M. urundeuva, isolated compounds and metal complexes were tested in nests of Atta sexdens rubropilosa (test of toxicity by ingestion), enzyme inhibition in AChE and fungicide test in ants symbiotic fungus (Leucoagaricus gongylophorus) withsignificative results.