953 resultados para Conformação de metais
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The refractory metal carbides have proven important in the development of engineering materials due to their properties such as high hardness, high melting point, high thermal conductivity and high chemical stability. The niobium carbide presents these characteristics. The compounds of niobium impregnated with copper also have excellent dielectric and magnetic properties, and furthermore, the Cu doping increases the catalytic activity in the oxidation processes of hydrogen. This study aimed to the synthesis of nanostructured materials CuNbC and niobium and copper oxide from precursor tris(oxalate) oxiniobate ammonium hydrate through gas-solid and solid-solid reaction, respectively. Both reactions were carried out at low temperature (1000°C) and short reaction time (2 hours). The niobium carbide was produced with 5 % and 11% of copper, and the niobium oxide with 5% of copper. The materials were characterized by X-Ray Diffraction (XRD), Rietveld refinement, Scanning Electron Microscopy (SEM), X-Ray Fluorescence Spectroscopy (XRF), infrared spectroscopy (IR), thermogravimetric (TG) and differential thermal analysis (DTA , BET and particle size Laser. From the XRD analysis and Rietveld refinement of CuNbC with S = 1.23, we observed the formation of niobium carbide and metallic copper with cubic structure. For the synthesis of mixed oxide made of niobium and copper, the formation of two distinct phases was observed: CuNb2O6 and Nb2O5, although the latter was present in small amounts
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Textile production has been considered as an activity of high environmental impact due to the generation of large volumes of waste water with high load of organic compounds and strongly colored effluents, toxic and difficult biodegradability. This thesis deals with obtaining porous alumina ceramic membranes for filtration of textile effluent in the removal of contaminants, mainly color and turbidity. Two types of alumina with different particle sizes as a basis for the preparation of formulation for mass production of ceramic samples and membranes. The technological properties of the samples were evaluated after using sintering conditions: 1,350ºC-2H, 1,450ºC-30M, 1,450ºC-2H, 1,475ºC-30M and 1,475ºC-2H. The sintered samples were characterized by XRD, XRF, AG, TG, DSC, DL, AA, MEA, RL, MRF-3P, SEM and Intrusion Porosimetry by Mercury. After the characterization, a standard membrane was selected with their respective sintering condition for the filterability tests. The effluent was provided by a local Textile Industry and characterized at the entry and exit of the treatment plant. A statistical analysis was used to study the effluent using the following parameters: pH, temperature, EC, SS, SD, oil and grease, turbidity, COD, DO, total phosphorus, chlorides, phenols, metals and fecal coliform. The filtered effluent was evaluated by using the same parameters. These results demonstrate that the feasibility of the use of porous alumina ceramic membranes for removing contaminants from textile effluent with improved average pore size of 0.4 micrometre (distribution range varying from 0,025 to 2.0 micrometre), with total porosity of 29.66%, and average percentages of color removal efficiency of 89.02%, 92.49% of SS, turbidity of 94.55%, metals 2.70% (manganese) to 71.52% (iron) according to each metal and COD removal of 72.80%
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It is located in an area of increasing oil exploration, the region of the Lower Açu is at the mercy of a possible pollution generated by this economic activity, which includes various chemical substances harmful to health, such as metals. This thesis aims to, diagnose the areas of River Piranhas-Açu, a region of the Lower Açu, which are polluted by traces factors and more. In this study, it was determined the concentration of the chemica elements Al, CD, Cr, Cu, Fe, Mn, Ni, P, Pb, V and Zn, through the technique of ICP-OES analysis and the size of sediments and their contents organic matter. Were mapped by GPS, 12 points from collections. The interpretations of the results, together associating that allowed pollution to a possible contamination by oil activity. The results showed tha some regions have low concentrations of cadmium, lead, copper, manganese and zinc unable to promote damage to human health. However, there are places where the concentrations of certain metals chromium, iron and zinc are moderately polluted compared to the results with the reference values of literature and others that are highly polluted by iron. However, due to a greater number of wells in production in those locations, those higher concentrations, it can be suggested a possible influence of oi production in some areas with concentrations of chromium and lead are higher than the rest of the points of monitoring. Moreover, it is observed that the highest levels of metals found in sediment of finer texture and more organic matter content
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Today a major responsibility for the contamination of soil and groundwater and surface water are establishments known as gas stations of fuel which has attracted increasing attention from both the general population as the state agencies of environmental control due to leaks in storage tanks and mainly to disruption of pipe corrosion of tanks and pumping. Other services, like oil changes and car wash are also causes for concern in this type of establishment. These leaks can cause or waste produced, and the contamination of aquifers, serious health problems and public safety, since most of these stations located in urban areas. Based on this, the work was to evaluate soil contamination of a particular service station and fuel sales in the city of Natal, through the quantification of heavy metals like Cd, Cu, Cr, Ni, Pb, Zn of total organic carbon (TOC) and organic matter using different techniques such as optical emission spectrometry with inductively coupled plasma source (ICP OES), Total Organic Carbon analyzer and gravimetric analysis respectively. And also to characterize the soil through particle size analysis. Samples were taken in 21 georeferenced points and collected in the same period. The soils sampled in sampling stations P3, P5, P6, P10, P11, P12, P13, P14, P15, P17, P18 and P20 showed the smallest size fractions ranging from fine sand to medium sand. The other study sites ranged from fine sand to medium sand, except the point P8 showed that only the type size medium sand and P19, indicating a particle size of the coarse type. The small correlation of organic matter with the elements studied in this work suggests that these are not of anthropogenic origin but geochemical support
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The decoction of Brazilian pepper tree barks (Schinus terebinthifolius, Raddi), is used in medicine as wound healing and antiinflamatory. Once extracts from this plant are used for acceleration of scar s process, it is important to study their mutagenic and genotoxic potential. In previous works in our laboratory, it was observed mutagenicity caused by the decoction when in high concentrations. Among the chemical compounds of this plant that could be able to induce mutation, the flavonoids were the only group that was referred to have either an oxidant or antioxidant potential. The flavonoids were isolated, purified and quantified by adsorptive column chromatography under silica gel, bacterial and in vitro genotoxic tests were realized to determine if the flavonoids were the responsible agents for this mutagenicity found. The tests realized with plasmidial DNA were indicative that the flavonoids are probably genotoxic, due to the presence of correlation between increase of the flavonoid concentration and in plasmidial DNA double strand breakage visualized in agarose gel, as well as they were capable to generated abasic sites shown by the in vitro treatment with exonuclease III. The same tests with plasmidial DNA in the presence of copper [10 µM] and of a Tris-HCl pH 7.5 [10 µM] buffer were realized with the isolated flavonoids to determine if there would be or not participation of reactive oxygen species (ROS). The transformation of plasmidial DNA in different bacterial strains proficient and deficient in DNA repair enzymes in the presence or not of a Tris-HCl buffer, suggests that the enzymes that repair oxidative lesions are necessary to repair the lesions generated by the flavonoids and that ROS are generated and are necessary to promote the lesions. Bacterial tests with Escherichia coli strains of the CC collection (deficient or not for DNA repair enzymes), showed that the flavonoids are able to increase the frequency of mutations, mainly in strains mutated in repair enzymes (MutM, MutY-glicosylases and double mutant), suggesting that these agents are responsible for the enhancement in the mutation rate. In order to determine the mutation spectrum caused by the flavonoids of the Brazilian pepper tree stem bark, plasmidial DNA previously treated with the flavonoids were transformed in bacterial strains deficient and proficient in the DNA repair enzymes, followed by a blue-white selection with X-gal, DNA amplification by PCR and sequencing the positive mutant clones. Analysis of the mutants obtained from strains CC104, CC104mutM, CC104mutY, CC104mutMmutY, BW9101, BW9109 indicated a predominance of some mutations like G:C to C:G that can be correlated with the origin of 8-oxoG, due to oxidative lesions caused by the flavonoids. So it can concluded that the flavonoid isolated or in fractions enriched on them are genotoxic and mutagenic, and their mutations are predominantly oxidative, mediated by ROS, and the lesions are recognized by the BER system. In this way it is proposed that the flavonoids can act in two different ways to generate the DNA lesion: 1. in a Fenton-like reaction, when the flavonoid are in the presence of metal ions and that together with the water generate ROS that promotes the DNA lesions; 2. in another way the lesions can be generated by the formation of ROS due to the internal chemical structure of the flavonoid molecule due to the quantity and location of hydroxyl groups, and so producing the DNA lesions, those lesions can be directly (suggested by the in vitro experiments) or indirectly done (supported by the experiments using the CC bacterial strains)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The occurrence of human cancer in the municipality of Lucrécia (RN, Brazil) has shown high frequencies (INCA, 2007). Tests of micronucleus (MN) and nuclear abnormalities (NA) were performed to assess the genotoxic potential of water from the Lucrécia dam, which is located in a semi-arid region under the influence of crop irrigation and irregular rainfall. Water samples were collected in this source for analyzing the concentration of cyanobacteria, metals and radioactivity. Erythrocytes of Nile tilapia (Oreochromis niloticus) were collected in dam and cells of human oral mucosa in the urban area of this municipality for the bioassays of MN and NA. In fish were also analyzed concentrations of metals in samples of liver and gills. The genotoxicity tests with biological samples of fish and humans have shown significant increases in the frequencies of MN and NA (p ≤ 0.05) and are indicative of increased DNA damage in relation to the control groups. In conclusion, the results obtained from water samples and biological municipality of Lucrécia indicates that the presence of chemical and microbiological pollutants, and increase of genotoxic in human of this municipality. We suggest the implementation of advanced water treatment, to prevent further degradation of the aquatic environment and decrease in the life quality. This research of environmental quality assessment was performed in order to contemplate a multi and interdisciplinary character of this water resource and that can induce genotoxic damage in the organisms in this study region
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The Caatinga is the predominant vegetation type in semi-arid region of Brazil, where many inhabitants depend on hunting and gathering for survival, obtaining resources for: food and feed, folk medicine, timber production, etc. It‟s the dry ecosystem with highest population density in the world. The early stages of development are the most critical during the life cycle of a flowering plant and they‟re primordial to its establishment in environments exposed to water stress. Information about adjustments to the growth of the species, correlated with their studies of distribution in Seridó oriental potiguar, are an important ecological and economic standpoint, because they provide subsidies for the development of cultivation techniques, to programs of sustainable use and recovery of degraded areas. This thesis aimed to study the initial growth and foliar morphology in plants like Enterolobium contortisiliquum (Vell.) Morong. (tamboril) and Erythrina velutina Mart. ex Benth (mulungu), species of occurrence in the Caatinga, under water stress. After sowing and emergency, the seedlings were exposed to three water regimes: 450 (control), 225 (moderate stress) and 112.5 (severe stress) mm of water slide for 40 days. Seeding occurred in bags of 5 kg and after the establishment of seedlings thinning was carried out leaving a plantlet per bag. At the beginning the waterings occurred daily with distilled water, passing to be on alternate days after thinning. Twenty and forty days after the thinning seedlings collections were held to be done analysis of growth and biomass partition. When compared to the control group, the treatments with water stress showed reduction in the growth of the aerial part, growth of the greater root, number of leaves and leaflets, dry leaf area and total phytomass in both species, but in general, this effect was most marked for E. velutina. Regarding the partition of biomass, there were few changes throughout the experiment. Morphological changes in the leaves as a function of stress were not significant, however, there was a trend, in both species, to produce narrower leaves, that facilitate heat loss to the environment. It has not been possible to establish a positive relationship between inhibition of growth and distribution of species, whereas E. velutina is a species of most common occurrence in Seridó oriental potiguar. In this way, other aspects should be taken into account when studying the adaptation of species the dry environments, such as salinity, presence of heavy metals, wind speed, etc
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The relation between State and civil society is not a very recent discussion, but it does not mean that debate is exhausted, since is in the historical context that the novelty is seized. Thinking like this, we may analyze how the relation between state and civil society happened in Acre during the decade of 1970. But, to understand how this relation is established in faraway Acre, we have available to the reader historical analyses, in a tireless attempt to clarify minimally aspects that characterize acreana society. To do this, we take on as a departure point, in general not differentiating of the given structure at national level, the conformation of this society was guided in a passive revolution, in another way, by high transformismo, relegating to the civil society, which is incipient, pífia a simple participation in the hegemonic policy direction. All this brings us to the thought that both state bureaucracy structure and the civil society organization, were influenced decisively for a traditional political elite. In addition, we begin the work with the lifting bibliographic reference searching and then we analyze the empirical reality, such as newspapers, official media publications and private, a few documents and last, interviews with political actors associated with the process consolidation of civil society in the 1970 decade. The interviewees were selected, firstly for their location in the region, and for their outstanding contribution to the consolidating process of recent Acre history. Thus, the interviews followed up on a semi-structured way, leading up, also, for the informations that the interviewees would have to pass on. The systematization and analysis of these surveys have shown us that, in the period before of the Acre Federal State lifting had, of course, a transformismo by high, but at 1970decade, the society with a more heterogeneous social formation, is not allowed, or at least, organize itself, to counter a systematic imposition. Thus, the hegemonic area of dispute between State and civil society occurs from the "reconciliation" with the adoption of public policies that amenizasse the dispute between both spheres, and to build up some bodies, settling a acreana civil society.
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Estudaram-se os efeitos da idade da vaca ao parto e da idade do animal à desmama, bem como os efeitos genéticos aditivo direto e materno e da heterozigose individual, sobre os escores visuais de conformação, precocidade e musculatura e ganho de peso do nascimento à desmama, de animais formadores da raça Brangus. Foram analisados 53.683, 45.136, 52.937 e 56.471 dados de conformação, precocidade e musculatura à desmama e ganho de peso do nascimento à desmama, respectivamente, de animais nascidos entre 1986 e 2002, provenientes do arquivo zootécnico da empresa Gensys Consultores Associados S/C Ltda. Os efeitos de ambiente e genéticos sobre as características em estudo foram analisados pelo método de quadrados mínimos usando modelos matemáticos que incluíram grupo de contemporâneos como variável classificatória e a idade da vaca ao parto, a idade do animal à desmama e os efeitos aditivo direto e materno e da heterozigose individual como co-variáveis. Todos os efeitos incluídos nos modelos afetaram significativamente as características avaliadas, com exceção do efeito da idade da vaca ao parto sobre o ganho de peso do nascimento à desmama e do efeito aditivo materno sobre todas as características estudadas. Os efeitos ambientais e genéticos revelaram-se importantes fontes de variação para as características estudadas e devem, pois, ser considerados na distinção e comparação dos animais para seleção.
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This dissertation deals with the possibility of build an effective social control of the judiciary Brazilians. The theme was bounded by a cut geographic and secular: the experience of the Center of Justice and Citizenship in the state of Rio Grande do Norte (OJC/RN), which begins formally in august 2003. The research approach and leave of experience in judicial practice and policy specific substrates to theorize about the subject. We collected documents about cases, the judicial diagnoses, reports, news material, in addition to lifting bibliographic. Therefore, it is working with about notions of a democratic state of right in the light of the Brazilian Constitution of 1988, in order to contextualize the insertion of the judicial system, by the prospect of legitimacy, which is considered by a look formal and material. It is a brief analysis of the system of official control of the judiciary (internal and external), is emphasizing its shortcomings functional and its corporate character, which suffers from poor conformation democratic. Then there is a discussion about the need to establish the social control of the judiciary, through the prism of relations of power that are locked in the judiciary, the lack of formal criteria for the guarantee of obtaining the correct judgment (laws, precedents and conscience of the judge), the problems of impunity and justice class, and from the examination of some cases, as the body of search. From this conjuncture, prepares to be an outline of shapes and the limits of social control, consonant the proposal erected in certain sectors of organized civil society, represented by the movement s social OJC. In the end, considerations are made on the legitimacy and constitutionality of OJC
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PETROBRAS, a Brazilian oil company, follows principles of public administration and from the Constitutional Amendment 9/95 in Brazil began to compete with other companies with the flexibility of the oil monopoly. In this new model started to use the simplified procedure for bidding so that could compete on equal terms. The ordinance that adopted a simplified procedure for bidding has been the subject of some criticism and lawsuits especially under the Court of Audit and the Supreme Court in Brazil. The analysis of their constitutionality, and the possibility of their use by other group companies is the theme of this work, and for this purpose, permeates through the notions of judicial review in the Brazilian law on the stage of law and economics analysis of the norm, and the principles applicable to PETROBRAS and the devices most frequently asked about the implementation of 2745/98 Decree. For this, the basic issue that should be investigated further is the regulatory power of the Federal Executive and the delegation of powers within the legislature and its conformation to the constitutional regency
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The economic regional integration is a phenomenon observed in numerous occasions inside the global economic reality. Watchful to that phenomenon, the 1988 s Brazilian constitutional order establish in its 4th article, single paragraph, the commitment to seek for the Latin- American integration, as a Fundamental Principle to the Brazilian Federative Republic. Regarding the mentioned constitutional disposition s realization, the Brazilian State celebrated, specially, the 1980 s Montevideo Treaty, creating the Latin-American Integration Association, and the 1991 s Asuncion Treaty, performing the duty to establish a common market, in sub regional level, with Argentina, Paraguay and Uruguay, called Mercado Comum do Sul. However, due to an addiction to a wrong comprehension of State s Sovereignty Principle, the Constitution imposes to the international rules an incorporation process, without providing any privilege to those ones regarding the integration constitutional disposition s realization, whether original or derived. The Brazilian s Supreme Court, as matter of fact, affirmed that it is not possible, facing the actual constitutional order, to grant any character of preference. Also in the controversies solution mechanism, responsible for the law s execution in case of its noncompliance, where found malfunctions, most notably the system s open character and its excessive procedural flexibility, in addiction to restricting the access of individuals. It follows from these findings, then, the lack of legal certainty provided by the Mercosul s legal system, considering its effects both international and within the Brazilian state. Among the possible solutions to reduce or eliminate the problem are using the practice of the so-called executive agreements in the Mercosul s original rules incorporation to the Brazilian state, the creation of a Mercosul s court of law and/or a constitutional reform
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The conceptions of the judicial function, the process and the factors of legitimacy of the norm of decision are changed according to the model of State (liberal, social democratic and constitutional). The right of access to justice, likewise, follows the ideals present in constitutional movements experienced in different historical moments. The deficit of legitimacy of the judiciary is recurring subject of study in the doctrine, especially in the face of democratic standards that permeate the current paradigm of state. Under the process law, the essential element for the distinction of the states based on the rule of law (formal and material) and the democratic constitutional state lies in the democratic guarantee of participation to the litigants in the process of elaborating the norm of decision. The concern about the participatory democracy and the concretion of fundamental rights has as presupposition the conception of popular sovereignty. Keeping this effort in mind, the civil procedure cannot be oblivious to such considerations, especially when it justifies its constitutional conformation from the institutionalization of discourse within the procedural field (democratic principle) and of the democratization of access to justice, leading to the necessary contestation of the theory of instrumentality of the process. The democratic prospects of civil procedure and the concern about the legitimacy of the rule of decision cannot be moved away from the analysis of the judicial function and the elements that influence the legal suit s progress. The computerization of the judicial process entails extensive modification in the way the judicial function is developed, in view of automation of activities held, of the eliminating of bureaucratic tasks, manual and repetitive, and of streamlining the procedure. The objective of this study is to analyze the dogmatic changes and resulting practices from the implementation of the Judicial Electronic Process (JEP), prepared by the National Council of Justice, under the parameters of procedural discourse and democratic access to justice. Two hypotheses are raised, which, based on a bibliographic-documentary, applied and exploratory research, are contested dialectically. The expansion of publicity of procedural acts and the facilitating of communication and practice of such acts are elements that contribute to the effective participation of the recipients of the norm of decision in its making process and, therefore, the democratic principle in the procedural field. Ensuring access (to the parts) to the case files and reasonable duration of the process along with the preservation of its founding principles (contradictory, legal defense and isonomy) are essential to ensure democratic access to justice within the virtual system