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Caracterização ambiental, florística e fitossociológica de uma Unidade de Conservação. Caso de estudo: Estação Ecológica de São Carlos, Brotas, SP
(Universidade Federal de São Carlos, 1999-11-18)
Feliciano, Ana Licia Patriota
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Cavalheiro, Felisberto
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https://lattes.cnpq.br/0158443345380578
The present work was carried oput to develop na environmental characterization and diagnosis of the Ecologic Station of São Carlos and to estabilish a basic for the knowledge of the ecology of the arboreal species present in this fragment of semideciduous seasonal forest to support the planning and management of this conservation unit, and also to allow the maintenance and conservation of theirs existing natural resources. The Ecological Station of São Carlos, located between the municipalities of São Carlos and Brotas, São Paulo State, Brazil, with an area of 75,26 ha, it is a forest fragment constituted of a deciduous seasonal forest and is limitd by sugar-cane crops and the Santana dam. As one of the Conservation Units of the São Paulo State without scientific information, it deserves a study about its characterization and boundaries together whith the knowledge of its floristics and phytosociology, to elaborate its zoning, using the Geographic Information System (GIS/IDRISI). The use of GIS was important to the environmental characterization of the area and its boundaries, to provide information on its hydrography, altimetry, slopes, soil, municipalies boundaries, road system, use and soil cover, which resulted in the thematic maps (altimetric, hydrographic, etc) and the environmental zoning. To evaluate the consequences of the fragmentation process of the study area, in view of the unknown biologic diversity, specially vegetation, the floristic and phytosociologic surveys were carried out as a starting point for various works to be further developed in the area. The study of the floristics and phytosociology of the arboreal stratum was carried out by means of four transects, in which blocks of 10 x 10 m were established. In addition, the level of infestation by vines on the trees and dead trees was evaluated. The survey allowed the identification of 97 species distributed among 37 families, from which Fabaceae and Meliaceae contributed with the highest number of species. Fifteen individuais were not identified at species level. From this total, four were identified at family level, ten at genus level and one is unknown. The diversity index obtained for the species in the studied area was of 3.55 nats/species. Three of the species found, Zanthoxylum riedelianum Engl., Trichilia hirta L., and Astronium fraxinifolium Schott are included among the endangered species, in the vulnerable category. With the results of arboreal flora found in the survey. The richness of families and species was found to be quite similar when compared to studies of other fragments of the State of São Paulo. The need of elaborating and accomplishing a specific management plan for the area is assential for maintenance and conservation of the associeated genetic resources of this conservation unit, due to the agricultural use of its boundaries.
Desenvolvimento sustentável e a sociedade da informação: uma parceria natural?
(Universidade Federal de São Carlos, 2000-01)
Furnival, Ariadne Chloe Mary
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https://lattes.cnpq.br/1291482506649810
Na forma de uma revisão da literatura, é examinada a hipótese de que o advento da chamada "sociedade pós industrial" ou "sociedade da informação" tem dado lugar a um período de atividade socioeconômico que representa uma mudança radical do modo anterior de desenvolvimento. É discutido o consenso de que a dinâmica desta nova forma de sociedade favorece um tipo de desenvolvimento econômico e social ecologicamente mais sustentável, principalmente porque o novo paradigma tem como seu eixo a informação e atividades relacionadas a ela, o que promoveria uma suposta "desmaterialização" da sociedade. A questão das formas com as quais este novo paradigma de desenvolvimento pode, ou não, afetar os chamados "países recém desenvolvidos" é também discutida.
Caracterização ambiental da reserva extrativista Chico Mendes (Acre-Brasil): subsídios ao plano de manejo
(Universidade Federal de São Carlos, 2000-02-25)
Costa, Suely de Souza Melo da
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Santos, José Eduardo dos
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https://lattes.cnpq.br/8533387365058570
The main objective of this work was the environmental characterization of 'Reserva Extrativista Chico Mendes , a Protected Area located in the state of Acre, Brazil. This analysis had a view to achieving a general diagnosis of the reserve environmental situation in the face of patterns of land and resource utilization and to providing an ecological basis for the planning of the sustainable exploitation of its natural resources. The methodology employed in this work involved the elaboration of a georeferenced digital data bank with thematic maps and morphometric information on hydrography, elevation, slope, soils, roads and human activities within the reserve area and in its surroundings (10 km buffer zone). Landscape structural elements were analyzed in 3 hydrographic basins identified in the hydrography map. These basins were further divided into 4 management units on which our study was focused. Our results show that RECM presents only 1% of its area modified by anthropic activities, heterogeneously distributed throughout the reserve and mainly associated to the location of colocações. The reserve surroundings have 16, 73% of its area modified by anthropic activities mainly located south and southeastern to the reserve. Predominant land uses in these areas constitute extensive cattle-raising and agriculture. We conclude from this analysis that the RECM has been playing its role as a Protected Area of sustainable use, particularly due to its great extension and low human demographic density. However its surroundings are fairly overtaken by various anthropic activities what suggests an urgent need for observing legal aspects of land utilization in the 10 km buffer zone around the reserve as well as constantly monitoring human activities within this zone and in its surroundings.
Programação da produção : uma abordagem por redes neurais artificiais.
(Universidade Federal de São Carlos, 2000-02-27)
Terra, Ana Rita Tiradentes
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Pereira, Neocles Alves
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https://lattes.cnpq.br/3744216524256924
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https://lattes.cnpq.br/2309862893058719
Production scheduling finds in the most detailed and complex level of production planning and control systems. Due to its nature combinatorial, several methods have been proposed to solve it. Among them there are the techniques of simulation systems and artificial intelligence approaches. This work presents a procedure of solution of production scheduling, through a hybrid model of simulation systems and artificial neural networks. In this procedure, the purpose of the artificial neural network is to learn the relationships between the priority rules designated to the machines of a production system, and the values of performance measures used to evaluate the scheduling. The objective is to analyze the differentiation among a group of combinations of priority rules through the evaluation of four performance measures. Results are presented and commented, highlighting the capacity of generalization of the hybrid model in prescribing priority rules to the machines, based on values of performance measures established by the user.
Avaliação do desenvolvimento do Camurim Centropomus parallellus (Poey, 1860) em água doce, submetido á alimentação artificial
(Universidade Federal de São Carlos, 2000-02-28)
Cavalheiro, José Marcelino de Oliveira
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Pereira, José Arlindo
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https://lattes.cnpq.br/7067270608207536
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https://lattes.cnpq.br/9600132550882670
Experiments with snook cultivation, Centropomus parallelus, aiming at increasing the continental pisciculture, mainly in northeast Brazil, were carried out in two stages. The first one was carried out at the laboratory of the Federal University of Paraíba, aiming to determine the optimum diet for increasing snook weight, in a 3 X 3 factorial treatment using feeds containing 35, 40, and 45% of crude protein and 3000, 3100, and 3200 kcal energy. The nine diets used here were prepared from ingredients obtained in the localities of the present study. They were added to 45 aquaria (50 L capacity each) with alevins obtained from spawning performed at a laboratory of the federal University of Santa Catarina, southern region of Brazil, presenting an initial average weight of 1.70g and stocked in a density ca 20 fish/m2, during a period of nine weeks. The best performance concerning the snook protein requirement was obtained by using 45% crude protein diet and with intermediary energy levels of 3100 kcal. On the second stage, fieldworks were performed in the municipalities of São Bento and Bananeiras, located in the mesoregion of sertão (microregion of Catolé do Rocha ) and mesoregion of agreste (microregion of Brejo ) in Paraíba State, respectively, where development of snooks obtained from spawning and fed with the best feed determined on the first stage, was estimated. The same management procedures were utilized in both localities. In São Bento, two aquaria (270m2 each) belonging to the fish farming Fazenda PROSAL Aquacultura S/A were utilized, from 26th May/1998 to 26th May/1999. In Bananeiras, two tanks (100m2 each) belonging to the Pisciculture Station of IBAMA (Insitute for the Environment and Natural Resources) were utilized, from 11th June/1998 to 11th June/1999. Both places were selected because they have the greatest number of pisicultures in Paraíba State. High fluctuations of limnological variables, mainly nutrients (ammonium, nitrite, and nitrate) occurred during the experiments acting upon snook, which showed to be a rough species. A positive and significant correlation (p (< ou =) 0.05) was obtained between zooplancton belonging to Other Organisms group (ostracods, chironomids, oligochaetes, insects larvae, etc) and the Weight Increase Rate. However, among the natural food occurring in the cultivation ponds (in São Bento) cladocerans were the snook favourite food, whereas in the tanks (in Bananeiras) Other Organisms group was its favourite food. Through the best adjusted values index (r2) obtained from several growth mathematical equations used here, the polynomial model showed to be noteworthy, despite significant differences between the snook groups development from the aquaria and from the tanks was not obtained.
O fundamento da moral: Schopenhauer critico de Kant
(Universidade Federal de São Carlos, 2000-02-29)
Santos Junior, Renato Nogueira dos
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Ferraz Júnior, Bento Prado de Almeida
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https://lattes.cnpq.br/7589245190503189
The aim of this dissertation is to present Schopenhauer's Metaphysics with a view to analysing the categorical imperative, a key concept of kantian morality. Our analysis shall indicate that the reason is merely an instrument of the will, which demands a refusal of the categorical imperative and the recognition of compassion as the cornerstone of morals.
Secagem de gel ágar
(Universidade Federal de São Carlos, 2000-02-29)
Moreira, Marcos Flávio Pinto
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Sartori, Dermeval José Mazzini
Agar-agar is a hydrofilic colloid extracted from seaweed, mainly from algae Gelidium. It s used as culture medium in microbiology and as emulsificant, stabilizer and gelling in foods. Drying is an important operation in the extractive process to obtain Agar-agar, because it defines the form, color and final moisture content of product. In order to study the drying of agar gel, equilibrium and drying experiments are needed. The equilibrium of agar-water-air was investigated using the static gravimetric method and drying experiments were performed in a forced convection dryer. To determine equilibrium moisture content values, the static method was used with saturated saline solutions where operational conditions of temperature and relative humidity ranged from 25.0°C to 50.0°C and 11.0% to 84.0%, respectively. The determination of moisture content was based on Lees method. The drying experiments were performed with temperatures from 30.0°C to 50.0°C and superficial air velocities from 1.0 to 4.0 m/s. Based on the experimental procedure above, the equilibrium of agar-water-air could be reasonable described by the G.A.B. (Guggenheim-Anderson-de Boer) model. It was verified, using Lewis equation, that temperature and velocity of air influence the drying operation. Finally, at a constant drying rate, the drying of agar gel and water are very similar. The constant drying rate of agar gel has been represented by a relationship for evaporation of water. The decreasing drying rate of agar gel was represented by the characteristic curve. All results obtained in this work serve as contribution to the process to obtain the agar, which utilizes the drying.
Desenvolvimento e caracterização de blendas Poli(tereftalato de etileno) - PET/ Poli(naftalato de etileno)- PEN
(Universidade Federal de São Carlos, 2000-03-03)
Nunes, Edilene de Cássia Dutra
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Agnelli, José Augusto Marcondes
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https://lattes.cnpq.br/7592090152400440
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https://lattes.cnpq.br/8361322278754916
The scientific and technological development of food packaging polymers has increased considerably over the last years, especially in relationship to packaging for beverages such as carbonated soft drinks and beer. As for carbonated soft drinks polyethylene terephthalate PET has been the most widely investigated polymer in virtue of its favorable intrinsic properties, and in recent years polyethylene naphthalate - PEN has attracted increasing interest as a result of its superior performance in relationship to PET in applications that demand higher technical requirements, however its major drawback is the high cost. One way of making PEN applications economically feasible is by blending with PET. Nonetheless, as these polymers are immiscible, conditions of process that enable an effective mixture should be looked for and, in some cases mixing of polyesters may lead to transesterification which favors miscibility between the polymers. In the current work four polymer blends were prepared from two types of PET and two types of PEN, both supplied by Eastman Chemical Company and Mitsui Co. Ltd. The premixing and processing conditions were studied, assessing the best combinations of pressure, temperature, cooling time. After specimen preparation all blends were characterized as to structural (FTIR, NMR), thermal (DSC, TGA, DMTA), mechanical (tensile test) and thermomechanical (HDT, Vicat) properties. NMR enabled confirmation and quantification of the transesterification reactions between the blend constituents responsible for blend miscibility and compatibility, notably the PET Eastman / PEN Eastman blend, which was the combination decided upon to be tested on industrial scale by injection molding of the parisons and posterior blow molding of 600 ml bottles, these were characterized in DCS, NMR and as to gas permeability.
A formação do educador reflexivo: um olhar sobre a construção de sua prática pedagógica
(Universidade Federal de São Carlos, 2000-03-15)
Lima, Paulo Gomes
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https://lattes.cnpq.br/5109357037661496
A finalidade deste artigo, longe de apresentar “receitas prontas” para a reversão de intervenções pedagógicas sem planejamento, preocupa-se em problematizar a formação do educador do ponto de vista de suas proatividade reflexiva. Esse exercício dá-se no decorrer da formação inicial e dos processos formativos ao longo da carreira, como veremos neste artigo.
A consciência na primeira tópica freudiana
(Universidade Federal de São Carlos, 2000-03-23)
Cossu Junior, Franco
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Monzani, Luiz Roberto
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https://lattes.cnpq.br/2036732603638197
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https://lattes.cnpq.br/8871513367560163
The principal aim of this entire work is to clarify the theorical statue about the counsciousness concept in the first freudian topography. In spite of the Uncounscious discovery and its central importance in the mental apparatus theory to the comprehension about pathologies as much as normality, the counsciousness never let to be a Freud`s constant worry, since the Studies on Histeria until the Metapsychology elaboration. If the counsciousness phenomenon, which is no longer central, may be considered an efect of surface and no more equivalent to the general psychism, it doesn`t renounce to be, although, the only way to the knowledge of the uncounscious phenomena.
Lacan e o estruturalismo
(Universidade Federal de São Carlos, 2000-03-23)
Felizola, Maria Cristina Merlin
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Simanke, Richard Theisen
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https://lattes.cnpq.br/5431145327759147
The present work has arisen of the need to understand the Lacan statement "the unconscious is structuralized as language". With this affirmation Lacan has pointed to two important directions: His incursion to the structuralism movement and the adoption of the Linguistics as reference. First we feel the necessity to know the structuralism movement and its bigger contributors. The structuralists have had much concern in searching a model which could explain the biggest possible number of aspects of a phenomenon, in a simpler and economic. In relation to the Linguistics the contribution came from the Fonology, this served as model for considering the terms in its internal relations, for introducing the structure notion and also searching the general laws construction. The formalization degrees that the Linguistics reach was such that it started to serve as influence for others disciplines of human being sciences, in their intention to ascend to the category of rigorous sciences. The structuralism brought a new method to approach the societies and the man. The unconscious, the primitive society and everything that had been depressed in the occidental History has found a place in the movement that searched the grammar of the human being thought.
Miragem da conquista: a religião na teoria freudiana da cultura
(Universidade Federal de São Carlos, 2000-03-24)
Carone, André Medina
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Simanke, Richard Theisen
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https://lattes.cnpq.br/5431145327759147
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https://lattes.cnpq.br/5392166032777488
Indicadores de sustentabilidade urbana: as perspectivas e as limitações da operacionalização de um referencial sustentável
(Universidade Federal de São Carlos, 2000-04-05)
Silva, Sandra Regina Mota
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Shimbo, Ioshiaqui
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https://lattes.cnpq.br/6315114291031702
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https://lattes.cnpq.br/9973870842834947
The complexity of the problems deriving from urban environments has required a deeper and more integrated understanding of the reality of these environments as an essential step toward solutions. The main purpose of this study is to investigate the applicability of principles of sustainability in the process of monitoring the socioenvironmental conditions of this medium. To gain a better understanding of the ideas surrounding the perspective of sustainability, the different meanings ascribed to the term, as well as the complementary issues and aspects that interact in this world of considerations are discussed. Thus, basic conceptual elements were sought that would contribute to build aproper definition for use within the context of this work, which in turn allowed for an outline to be made of its essential characteristics and general guiding principles that were then employed to analyze a given set of indicators. Different reflections and proposals regarding the instruments used to evaluate urban conditions were examined to identify a set of variables defining the basic characteristics of projects and implementation. A critical systematization of three previously selected experiences the Agenda 21 Indicators, the Seattle Indicators and the Belo Horizonte Urban Life Quality Index led to the elaboration of an analysis based on the general principles of sustainability and on the set of variables existing in the process of creating, formulating and monitoring these indicators. This analytical repertoire allowed for a definition of the potential represented by these instruments, offering the basic references for its development and implementation in different contexts.
Limnologia comparativa de três lagoas neotropicais da Bacia do Magdalena Médio Santandereano (Colômbia), com ênfase no estudo da diversidade da comunidadezooplanctônica e sua relação com a dinâmica hidrológica do sistema regional
(Universidade Federal de São Carlos, 2000-04-14)
Diaz, Rosa Aura Gavilán
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Tundisi, Takako Matsumura
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https://lattes.cnpq.br/7789295211200946
Few studies have been developed regarding zooplankton diversity in Neotropical Region, particularly in Colombia. Regarding the diversity in the Tropical region still there are a great controversy, despite the relevance of this community as indicator of climate or hydrological, physical and chemical changes. A limnological study was performed during the period between January, 1998 and January 1999, in three shallow lakes ( ciénagas ) belonging to Rio Magdalena Basin, Middle Santandereano,-Colômbia. At monthly intervals a set of physical, chemical and biological variables were measured in a sampling station at the central region of the lakes. The effects of rainfall and water level on Shannon-Wiener zooplankton diversity index were analyzed. Also analyses of taxonomical composition and relative abundance of zooplankton community as a whole or for the Rotifera, Cladocera and Copepoda were performed showing differences among the lakes. A similar thermal structure with microstratification in surface layers and gradual decreases with depth was observed. Maximum temperature value found was 38º C in the surface and 26.8ºC at the bottom. Physical and chemical conditions varied along the hydrological cycle, although there was not a defined pattern except regarding nutrient concentrations that was observed to be higher in the lowest water level and suffering dilution in the wet period for all lakes. The highest values of Chlorophyll a (229.2 µg.L-1) and net primary production (3203 mg C m2d-1) were found in Ciénaga of Chucuri Lake. It appears that there is an inverse relationship between total zooplankton densities and chlorophyll a concentrations. The highest richness of taxa was observed in Ciénaga El Llanito. Rotifers had the highest annual numerical relative abundance and also the highest taxonomical richness in all lakes, throughout the hydrological cycle. There appears to be an alternation in the dominance of species for each particular group of zooplankton in the three ciénagas However it does not appear to be a succession pattern. The highest Shannon-Wiener índices were obtained for Ciénaga de Paredes (4.12 bits.ind-1) and the smallest for Ciénaga de Chucurí (1.24 bits.ind-1) and simultaneously a higher equitability was found, suggesting that the highest diversity indices were related to uniformity. There was no correlation found among water level fluctuation and zooplankton density as a whole, but this exists when the component groups were considered alone, as it was found for Cladocera in Ciénaga de Paredes. The absence of correlation among zooplankton diversity indices and water level fluctuations suggest that each group probably responds to multiple interacting factors in each lake.
Processos estocásticos de reação e difusão na rede e cadeias quânticas
(Universidade Federal de São Carlos, 2000-06-02)
Mendonça, José Ricardo Gonçalves de
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Alcaraz, Francisco Castilho
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https://lattes.cnpq.br/9538405812117662
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https://lattes.cnpq.br/8792749813872106
In this work we investigate some reaction-difusion stochastic processes on the lattice. In particular, we determine the universality classes of critical behavior of a nonequilibrium surface growth process and of the basic contact process. Our main tools of investigation are exact numerical diagonalizations and finite-size scaling ideas. We also present an application of the Bethe ansatz in the exact diagonalization of the infinitesimal generator of a di_usion process of particles without exclusion known as the zero range process.
Caminhos da universidade rumo ao século XXI: pontos e estratégias para a sua orientação na visão de educadores brasileiros
(Universidade Federal de São Carlos, 2000-08)
Lima, Paulo Gomes
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https://lattes.cnpq.br/5109357037661496
A principal preocupação desse estudo é, através das reflexões nele contidas, apontar caminhos que poderão contribuir para que as nossas universidades, face à inevitável globalização, possam se instrumentalizar de forma coesa, de modo a cumprir sua missão na formação e transformação do homem. Para tal, organizamos esse trabalho sobre a universidade partindo de sua gênese, passando pelo momento atual e chegando até as perspectivas que se tem da universidade pretendida para o próximo milênio; para isso foram coletados dados que permitiram analisar alguns de seus problemas e, através dessa análise levantar possíveis soluções frente ao emergente século XXI.
La formación del educador reflexivo: notas para la orientación de sus prácticas
(Universidade Federal de São Carlos, 2000-09)
Lima, Paulo Gomes
;
https://lattes.cnpq.br/5109357037661496
La práctica pedagógica es el termómetro que esclarece la realidad del aula, revelando inequívocamente la relación de compromiso (o la falta de él) del educador con sus estudiantes y con la educación. Nótese que no usé la palabra “involucramiento”, pero sí “compromiso”, pues la primera denota una relación superficial, “un entregarse por la mitad”, “un jugarse” sin creer verdaderamente en su misión, en sus efectos reales para la transformación del hombre y del mundo; “para conformar el sentido de la obligación que la docencia conlleva”. La segunda palabra por la cual personalmente tengo preferencia, infiere la acción concreta de “abrazar la educación totalmente”, de “rendirse a ella”, no sólo por el sentido de la obligación de la profesión o por el significado literal que la propia palabra “compromiso” trae consigo, sino porque establece una perennidad que es la fuerza motriz del pensar y vivir de la educación.
Controle da volatilização de inibidores voláteis de corrosão através de suporte de alumina
(Universidade Federal de São Carlos, 2000-10-20)
Panza, Luciana Paula
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Kuri, Sebastião Elias
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https://lattes.cnpq.br/6842072916153866
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https://lattes.cnpq.br/6443072583987507
During the process of the fabrication, storage and transport of equipments, the control of metallic corrosion can make though vapor phase corrosion inhibitors (VCI). These inhibitors are, generally, organic salts deriving from powerless acids and moderate powerful bases and posses, how principal characteristic, high vapor pressure, that for them confer great volatily. Meantime, the majority of the volatile inhibitors utilized contain in these compositions nitrite ion that accordant the new ecologic legislation, is a harmful agent to nature and human. This work discusses the principals polemics created to ISO 14000 and propose a comparative study between traditionally and news inhibitors free of nitrite ion. So, the VCIs were submitted to the thermogravimetric analysis tests and were verify the mass detriment with the changes of the temperature. Following, isothermic tests was realized and was computed the linear volatization velocity constants to the different inhibitors. The efficiency of the inhibitors was verified through the systems containing the different VCIs and the accompanying of the corrosion happened since the beginning for the optical microscopy.
Os efeitos da adaptação do PECS associada ao Curriculum funcional natural em pessoas com autismo infantil
(Universidade Federal de São Carlos, 2000-11-16)
Walter, Catia Crivelenti de Figueiredo
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Almeida, Maria Amélia
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https://lattes.cnpq.br/4061818490832341
Communication disorders in persons diagnosed with autism, generally are severe and bring difficulties to their interpersonal relationships, putting them apart, being not comprehended by the majority of other people. The main objective of this study was to evaluate the effects of the adaptation of the Picture Exchange Communication System (PECS) applied in the context of a natural functional curriculum (adapted PECS) in the communication of persons diagnosed as autistic, who do not presented oral language and/or functions speech at the beginning of the study. As a secondary objective, the study had the intention to verify if the adapted PECS would help the participants to begin to use of speech. The study was conducted at Centro Ann Sullivan do Brasil (CASB), located in Ribeirão Preto City São Paulo State. In order to verify the effects of the intervention, an AB simple subject research design was applied and replicated within four boys with ages varying from 5 to 8 years old, diagnosed as autistic. The study involved two phases: baseline and intervention. In order to train the 5 phases of the adapted PECS, the PCS (Picture Communication System) pictures was used. The training and data collection sessions were held during 2 years. The results showed that all participants presented changes in their communicative behavior and acquired an expressive vocabulary in some words, some sounds and in the use of pictures, that varied from 25 to 61, all being used with communicative function. The obtained data suggests that the use of pictures with interaction and solicitation objective of something very much desired, seems to contribute to the emission of speech, sounds and gestures, used with communicative function by the participants. However, other studies must be encouraged, as well as the adapted PECS extension to persons with different diagnoses, who are able to benefit from any alternative communication system. The study concludes, since the PECS communication system has a basic element the interested picture exchanging by the participants through an interactive action, could contribute, in the future, to the inclusion process, not only at school environment, but also to home and community
Estudo de pós cerâmicos de PbTiO3 utilizando-se o método dos precursores poliméricos
(Universidade Federal de São Carlos, 2000-11-30)
Paris, Elaine Cristina
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Longo, Elson
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https://lattes.cnpq.br/9848311210578810
THE STUDY OF PbTiO3 (PT) CERAMIC POWDERS USING THE POLYMERIC PRECURSOR METHOD was started by the preparation of a precursor solution of metallic cations. Citric acid was used as quelation agent and ethylene glycol as esterification and polymerization agent. This solution was submitted to thermal treatment at temperatures about 300°C for the pyrolysis of the obtained polyester. PT crystalline powders were obtained starting from amorphous precursors, varying the calcination conditions as the temperature, the time and the furnace atmosphere. The evolution of the crystallization process of the PT was accompanied by X-ray diffraction (XRD), Raman spectroscopy and infrared spectroscopy (FTIR). It was verified that the beginning of the crystallization of the PT occurs at a temperature below the Curie temperature of the material (~ 490°C). Heat treatments for one hour at 400°C yields PT crystalline and free of secondary phases. It was observed that the formation of the PT phase takes place without the formation of an intermediary carbonate phase that can occur in perovskites obtained by the polymeric precursor method. It was verified that there was no formation of pyrochlore or fluorite intermediary crystalline phase, and the only intermediary phase found was cubic PT in some calcination stages. This indicates that the polymeric precursor method provides the homogenization of the ions at the molecular level, during the synthesis process. Aiming at a better understanding of the crystallization process, a comparison was performed between the amorphous and crystalline powders by means of X-ray absorption, using EXAFS (Extended X-Ray Absorption Fine Structure) and XANES (X-Ray Absorption Near Edge Structure) spectra. It was thus verified that the amorphous powders present a short distance structure formed by sixfold oxygen titanium coordination coexisting with fivefold oxygen titanium coordination. Photoluminescent property at room temperature was detected in the amorphous powders. It was verified by reflectance spectra the presence of a tail and of optical exponential borders which are characteristic of amorphous semiconductors. It was also verified that these tail and borders are sensitive to the temperature and to the time of calcination. With the increase of the degree of crystallization of the material and the consequent ordering of the crystalline phase, this luminescent property disappears. By means of theoretical calculations it was possible to verify that the amorphous powder induces electronic levels in the area of the band gap of the material. This fact favors the recombination of the electron-hole pair, which is possibly the responsible for the photoluminescence.