994 resultados para elementos de transición


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This work presents the analysis of an antenna of fractal microstrip of Koch with dielectric multilayers and inclinations in the ground plane, whose values of the angles are zero degree (without inclinations), three, seven and twelve degrees. This antenna consists of three dielectric layers arranged vertically on each other, using feeding microstrip line in patch 1, of the first layer, which will feed the remaining patches of the upper layers by electromagnetic coupling. The objective of this work is to analyze the effects caused by increase of the angle of inclination of the ground plane in some antenna parameters such as return loss, resonant frequency, bandwidth and radiation pattern. The presented results demonstrate that with the increase of the inclination angle it is possible to get antennas with characteristics multiband, with bigger bandwidth, and improving the impedance matching for each case analyzed, especially the larger angle

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This work proposes a formulation for optimization of 2D-structure layouts submitted to mechanic and thermal shipments and applied an h-adaptive filter process which conduced to computational low spend and high definition structural layouts. The main goal of the formulation is to minimize the structure mass submitted to an effective state of stress of von Mises, with stability and lateral restriction variants. A criterion of global measurement was used for intents a parametric condition of stress fields. To avoid singularity problems was considerate a release on the stress restriction. On the optimization was used a material approach where the homogenized constructive equation was function of the material relative density. The intermediary density effective properties were represented for a SIMP-type artificial model. The problem was simplified by use of the method of finite elements of Galerkin using triangles with linear Lagrangian basis. On the solution of the optimization problem, was applied the augmented Lagrangian Method, that consists on minimum problem sequence solution with box-type restrictions, resolved by a 2nd orderprojection method which uses the method of the quasi-Newton without memory, during the problem process solution. This process reduces computational expends showing be more effective and solid. The results materialize more refined layouts with accurate topologic and shape of structure definitions. On the other hand formulation of mass minimization with global stress criterion provides to modeling ready structural layouts, with violation of the criterion of homogeneous distributed stress

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The corpus of this work constitutes an analysis the literary work As Filhas do Arco-Íris, by Eulício Farias de Lacerda, considering object of study myths, legends and popular stories as estruturant elements of the romance. The unchainment of this reading considers aspects of the oral tradition as starting point for the rupture tradition. In that perspective, it became fundamental to describe aspects of the popular culture that consolidated the Brazilian Literature during the 20th century. Like this, it was necessary to understand the development of oral elements and the structuring of the folk-tales, pointing out that As Filhas do Arco-Íris was built in a especial way with regionalist characteristics, following the parameters of the romances published among the years 1930 and 1950. In the researched work, it was noticed a narrative that gathers stories, legends, myths, proverbs and oral locutions. In this, it reveals that the Brazilian literary production grew in aesthetics and thematic. Like this, As Filhas do Arco-Íris is an exercise of the experience regionalist inserted in the contemporary novel, because even with your first publication in 1980, the narrative is configured to the molds of a Romance de 30

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This dissertation aims to present a elementar vision of thomistic thought about human sexuality from knowledges of vices and virtues. Introduce the notion of vice as otherwise to human nature and seek its etymological meaning, approaching with the neotestamentary perspective of sin and malice. This notion is based in aristotelian and augustinian notion, used by Thomas Aquinas. Also present two virtues inside of the christian thought about the sexuality. They are temperance and chastity. The temperance is a virtue that orders the pleasures of tact, and regulates the chastity. Finally, we show that is possible in thomistic thought admit the legitimacy of sexual pleasure and also the natural necessity in relations, and this relations just can be designed inside of legitimate marriage

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This study aims to determine the amount of nutrients and toxic elements in aquatic macrophytes of species Eichhornia crassipes present in River Apodi/Mossoró - RN and check some of the possibilities of using the biomass produced, based on the influence of space - temporal and physiological absorption of nutrients by plants. For this, was determined: Leaf area, Leaf wet mass, Leaf dry mass, Real humidity, Apparent humidity, Ash, Total nitrogen, Crude protein, Calcium, Magnesium, Potassium, Total phosphorus, Sodium, Iron, Copper, Manganese, Zinc, Nickel, Cobalt, Aluminum, Cadmium, Lead and Total chromium at different times, 2 sampling points and 2 parts of plants (leaves and roots). The results show that the levels of nutrients, protein and toxic elements present in plant tissue of Eichhornia crassipes are influenced by spatial, temporal and physiological variability. In general, because the maximum values in the dry matter for total nitrogen (4.4088 g/100g), crude protein (27.5549 g/100g), total phosphorus (0.642 g/100 g), calcium (1.444 g/100g), magnesium (0.732 g/100 g), potassium (7.51 g/100 g), copper (4.4279 mg/100g), manganese (322.668 mg/100g), sodium (1.39 g/100g), iron (194.169 mg/100g) and zinc (3.5836 mg/100g), there was the possibility of using biomass of Eichhornia crassipes for various purposes such as in food animal, products production for human consumption, organic fertilizers, fabrication of brick low cost, and crafts. For all these applications requires a control of the levels of substances in plant tissue. Based on the levels of nutrients and crude protein, the younger plants (0 Month) would be best to have their biomass used. Moreover, one factor that contributes to the use of larger plants (6 Months), the levels of toxic elements which have significantly small or below the detection limit. Therefore, further studies quantifying the biomass produced/m2 at 0 and 6 months are needed for a more correct choice for the best time of harvest

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This study aimed to identify and review of the conceptual differences presented by authors of books, focusing on the theme of electronic configuration. It shows the changing concepts of electronic configuration, its implications for the cognitive development of students and their relations with the contemporary world. We identified possible obstacles in books generated in the search for simplifications, situations of different concepts of energy in the electron configuration for sublevels. For this analysis was carried out in several books, and some other general chemistry and inorganic chemistry without distinguishing between level of education, whether secondary or higher. It was found that some books for school books corroborated with higher education, others do not. To check the consistency of what was discussed, it was a survey of 30 teachers, it was found divergent points of responses, particularly with respect to the energy sublevels and authorship of the diagram which facilitated the electron configuration. It was found that the total 22professores, ie, 73,33% answered correctly on the energy sublevel more calcium (Ca) and 80%, ie, 24 teachers responded incorrectly on the iron. As for the authorship of the diagram used to facilitate the electronic configuration, we obtained 93, 33% of teachers indicated that they followed a diagram, and this was called "Diagram of Linus Pauling," teacher 01, 3,33%, indicated that the diagram was authored by Madelung and 01, 3,33%, did not respond to question. Was observed that it is necessary a more detailed assessment of ancient writings, as the search for simplifications and generalizations, not so plausible, lead to errors and consequences negative for understanding the properties of many substances. It was found that quantum mechanics combined with spectroscopic data should be part of a more thorough analysis, especially when it extends situations atoms monoelectronicpolieletrônicos to describe atoms, because factors such as effective nuclear charge and shielding factor must be taken into consideration, because interactions there is inside an atom, described by a set ofquantum numbers, sometimes not taken into account

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Although there are many studies on urban dust contamination by heavy metals in developed countries, little attention has been paid to this type of study in developing countries, including Brazil. Therefore, a series of investigations were performed to provide signatures of heavy metals in urban dust and assess the potential sources in the city of Natal - RN-Brazil. The fraction of these sediments was studied to pass through a sieve of 63 micrometers. For the study analyzed two groups of samples, one collected in September 2009 at the end of the rainy season (9 samples) and one collected in January 2010 in the dry season (21 samples). So in all, thirty sediment samples were collected from the street. Then, in Fluorescence Spectrometry X-rays were determined major elements SiO2, Na2O, K2O, Al2O3, MgO, P2O5, Fe2O3, MnO, TiO2 and CaO, and trace Rb, Cr, Ni, Cu, Zn, Sr and Pb by an ICPOES was determined Zn, V, Na, K, Ni, Mn, Mg, P, Fe, Cr, Cu, Pb, Ba, Ca and Al from leaching HCl 0.5 mol L-1 . The results of the concentrations of elements show that the greater presence of these occurs in the dry season, except for Si which is higher in the rainy season. Analyses by geoaccumulation Index (IGEO) Enrichment Factor (EF), Contamination Factor (CF), analysis correlation and Hierarchical Cluster, confirm that Zn, Cu and Pb is anthropogenic character. Zinc may be derived from various sources related to motor vehicles or the road signs and street grids. The elements Na, K, Mg and Ca may be related to droplets suspended in air containing cations and anions present in seawater (salty), common in Christmas throughout the year, brought by winds SE-NW. The elements Na, Mg, Ca and K are the most abundant in seawater and were analyzed in this study. This indicates that the source of these additional elements detected by analyzing the contamination factor may be the very sea. Moreover, Ni, Fe, Cr and Ba can be either as a source of anthropogenic geogênica. The source of Ca is different, because it comes in lime and paint (painting guides of buildings and streets) in construction materials, but may also be present in sediments in the fragments of shells or carbonate bioclasts common in the coastal area

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This study contributes to a critical synthesis of the principle of literary warrant, initially formulated by Hulme in 1911. Hulme proposed that the terms of a classification system should be derived from the literature to be classified, rather than based on purely theoretical considerations. Founding literary warrant on literature which is actually documented rather than on scientific or philosophical classifications or on the supposed authority of the first classificationists implied a clear departure from the conceptions of Harris and Dewey, who had used the classifications of Bacon and Leibniz as models. The validity of this principle over the past century is studied by means of diverse documental data (entries in dictionaries, retrieval by Google, etc.), as it is recognized as a main methodological element for classification standards and systems. This study also discusses the situation with respect to the top-down or bottom-up methodologies of system design. Three traditional applications of literary warrant are described as well as three new applications are suggested, in light of its methodological potential. It is possible to conclude that this principle will find increasing applications in other contexts, within and beyond Information Science.

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Specificity and updating of the bibliographic classification systems can be considered a determinant factor to the quality of organization and representation of the legal documentation. In the specific case of Brazil, the Brazilian Law Decimal Classification, does not foresee specific subdivisions for Labor Law procedures. In this sense, it carries out a terminological work based on table of contents of doctrinal Labor Law books of the mentioned area, which are compared to the conceptual structure of the Brazilian Law Decimal Classification. As a result, it presents an extension proposal for Labor Procedures as well as a methodological background for further extensions and updates.

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This study analyzes the perceptions of technical and administrative UFPA, in relation to the insertion of the components and assumptions of DBP in evaluation practice. Addresses the history, concepts, meanings, about AD methods, skills, evaluation skills, the APF and AD UFPA and Programme itself. The research is characterized as a hypothetical-deductive, descriptive and applied, using the case study. Data were analyzed using a quantitative approach, using the descriptive and inferential statistics. Data were collected through the application of questionnaires to 222 technical and administrative searched IFES, not occupants of FG and CD. The results indicate that the factors perceived in relation to the constituent elements such as: evaluation practice, measurement of competence, program management, timing, individual skills and fundamentals of the program and those related to assumptions such as: democratic process, integrative perspective, character development and pedagogical continuous evaluation practices are perceived in the evaluation process. The study concludes that comparing the results of the constituent elements and assumptions of the PAD of thechnical-administrative UFPA, it can be said about a tendency to change, though subtle, compared to the traditional model of AD, directed only to the granting of career progression for a new logic based on the results, showing an early effectiveness of the program evaluation practice by law and by the Institution. The results are confirmatory of advance evaluation practice in the institution, more so than has previously been expected, which demonstrates the value of scientific criteria of scientific research

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The Curimataú estuary is located in the oriental coast of Rio Grande do Norte State in Brazil. Its importance resides in the fact that this region possesses one of the last portions of preserved mangrove in the Rio Grande do Norte State. Nevertheless, it has been severely affected by many anthropogenic activities, as sugarcane monoculture and shrimp farming. Former works demonstrated that an accumulation of heavy metals is occurring in oysters in this estuary, and perhaps it could be explained by the input of metals in this ecosystem deriving from the shrimp farming. To better understanding the origin of these metals, bottom sediment samples, cores and suspended particulate matter were collected for a characterization of metal concentrations (Al, Ba, Cd, Cu, Cr, Fe, Mn, Ni, Pb, Zn) and to determine the potentially bioavailable metals. Additionally, the enrichment ratio for each element analyzed was calculated. The mineralogical composition of sediment samples and cores were obtained by X-ray diffraction. Moreover, data of orbital remote sensing were used in order to detect and quantify suspended matter by applying a logarithmic algorithm. Geochemical data of bottom sediments and cores revealed that, excepting Ba and Pb, the elements analyzed presented concentrations characteristic of an unpolluted ecosystem (Al: 0,25 - 8,76 %; Ba: 3,03 - 870 µg.g-1; Cd: < 0,25 µg.g-1; Cr: 1,72 - 82,4 µg.g-1; Cu: 0,12 -25,3 µg.g-1; Pb: 0,38 - 23,7 µg.g-1; Fe: 0,10 - 5,82 %; Mn: 15,1 - 815 µg.g-1; Ni: 0,14 - 36,1 µg.g-1; Zn: 1,37 - 113 µg.g-1). During the dry season a distribution pattern was observed, with higher metal concentrations in the margins, decreasing toward the central portion of the channel. These metal concentrations were well correlated with mineralogical compositions, with clay minerals prevailing at the margins, and quartz and feldspar in the center. However, this pattern was not observed during the wet season, probably because of the high water flux that disturbed bottom sediments. But, as observed for the dry season, a good correlation between metal concentrations and mineralogical composition was also observed for the wet season, with high metal concentrations where there were high quantities of clay minerals. Low enrichment ratios were obtained for the majority of elements analyzed, excepting for Mn, Ba and Pb. Manganese presented the higher ratios downstream for both seasons, and it can be an evidence of anthropogenic impact by shrimp farming. As barium and lead concentrations in sediment samples presented analytical problems during the total sample digestion, one cannot be sure that the ratios obtained correspond to the reality. The highest metal concentrations in particulate matter were obtained in the portion dominated by fluvial transport for all metals analyzed, excepting for copper. Barium and zinc were the only elements that presented elevated concentrations that are not common of unpolluted ecosystems (Ba: 5730 - 8355 µg.g-1; Zn: 3899 - 4348 µg.g-1). However, these high concentrations could not be related to the shrimp farming and waste waters from the town of Canguaretama, once they were obtained from the fluvial particulate matter, that is upstream from the activities above mentioned. The application of the logarithmic algorithm to the processed LANDSAT image was well succeeded, although the acquired image does not correspond exactly to the field campaigns. The IKONOS image provided very detailed views of the suspended sediment concentration at the estuary, as the mixture of distinct water flows at the confluence of Cunhaú and Curimataú rivers, with more turbid waters from Cunhaú river, that is directly affected by effluents from shrimp farming and urban waste waters deriving from the town of Canguaretama

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The study area is inserted in Ponta do Tubarão region, Macau City, setentrional littoral of Rio Grande do Norte State, composed of Tertiary and Quatemary sedimentary rocks and sediments. This region is characterized for the intense action of the coastal processes, causing the morphologic instability in part of the area, beyond the interference of human activities, as the Petroliferous Industrial Polo, salt companies and shrimp farms. This justifies the integration of multidisciplinary and multitemporal detailed scientific studies dealing with the evaluation of the changing behavior of this coastal environment by geoenvironments elements characterization, identifying protected and recuperation areas, mainly those under socioeconomic intervention. The main objective was the coastal monitoring using geoprocessing techniques to prepare thematic maps useful for oil spilling environment risk areas survey. The methodology was based on multitemporal interpretation of remote sensing images and field checking, integrated in a Geographical Information System (GIS). The Geologic, Geomorphologic, Vegetation, Soil and Land Use maps were prepared, and later on they allowed the generation of the Natural Vulnerability and Environmental Vulnerability maps. These maps had been classified in accordance with vulnerability degrees: very low, low, medi um, high and very high. Beyond these maps the GIS allowed the analysis of the shoreline evolution for 10 distinct dates, using Landsat 5 TM and 7 ETM+ and SPOT-HRVIR images. This analysis made possible the attendance of the coastal morphodynamic evolution, where the results had been represented by areasof erosion and accretion (or deposition) of sediments, pointing critical areas under erosive process to the petroliferous industry (Macau and Serra fields). The GIS also provided to prepare the Environmental Sensitivity Maps of Oil Spill (SAO Maps) in operational scale (1: 10.000), according to the norms ofthe Ministério do Meio Ambiente (MMA 2002). The SAO Map in operational scale was based on IKONOS images mosaic where the ESI (Environmental Sensitivity Index) was represented according with two tides phases of theregion. Therewere recognizedfiveESI (3, 4,7,9, 1O) for the low tide; to the high tide the ESI number increased to seven (3, 4, 5, 7, 8, 9, 10). All these information are necessary to the decisions making about oi! spill and its derivatives containment. These techniques application makes possible the optimization and implantation ofnew socioeconomics activities of low environmental impact, indicates areas for better productivity and security exploration, and benefits local communities with fauna and flora preservation. The development of these activities is inserted in the scope of Monitoramento Ambiental de Áreas de Risco a Derrames de Petróleo e Seus Derivados Cooperation Project (Rede 05/01 - PETRORISCO, FINEP/CTPETRO/PETROBRAS) of multidisciplinary and interinstitucional characteristics dealing with subjects involving the environmental monitoring and the petroliferous activity

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This study aims at analysing the (re) prodction of urban space in the south sone of Natal city, in particular the influence of the shopping-centers in this process. In this respect, it also analyses the changes of habits and constumes for part of the society, when those entreprizes were built in better-off areas of the south zone Natal as well as the transformations in the surroundings of the thre main shopping-centers. A sother commercial establishments of the same size, two out of the three main shopping-centers in the city are targered towards the better-off population. However, if compared to the others, one these has, for some time, sought to target a lower in come population. In spite of being an important element in the (re)production of urban space as well as in the cities modern commercial sector, these large commercial entreprizes reinforce capitalisms contradctions in so far as they constitute semi-public space whit an exclusionary and segregatory vatune

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Opossum is considered one of the most primitive mammals, with transition evolutive characteristics. In mammals, the aorta artery is referred as the main body blood vessel. The arteries wall structural organization follows a basic pattern, being contituted of three tunics: Intima, Median and Adventicial. After euthanasia, three samples of opossum had segments from the aorta artery ascendent, thoracic descending and abdominal descending portions removed, fixed in phormalin at 10% for 48 hours. Then, the material was washed in alcohol 70% several times, dehydrated in alcohois of growing concentrations, diafanized in xylol and included in "paraplast". Cuts with 5 to 7 mu m of thickness were placed in histological laminae and submitted to color methods of Hematoxilin-Eosin, Masson, Mallory and Calleja Tricromics. It was observed that in the different portions ascendent, thoracic and abdominal descending of aorta, the intima tunic presents much thick, made up of a layer of smooth muscular cells and elastic fibers, forming a limiting internal elastic membrane. In the three portions studied, the median tunic was the most evident layer, constituted of colagen fibers, smooth muscular cells arranged in a circular manner and elastic fibers, showing a variation in the mural elements proportion. It was evidenced the presence of a external elastic lamina, marking the transition between the median and adventicial tunic, formed by elastic fibers condensation. The aortic adventicial tunic showed to be little organized, having in its structure predominantely colagen fibers beans with some isolated smooth muscular fibers or in small fascicules among a few elastic fibers.