999 resultados para Modificação


Relevância:

10.00% 10.00%

Publicador:

Resumo:

The production of water has become one of the most important wastes in the petroleum industry, specifically in the up stream segment. The treatment of this kind of effluents is complex and normally requires high costs. In this context, the electrochemical treatment emerges as an alternative methodology for treating the wastewaters. It employs electrochemical reactions to increase the capability and efficiency of the traditional chemical treatments for associated produced water. The use of electrochemical reactors can be effective with small changes in traditional treatments, generally not representing a significant additional surface area for new equipments (due to the high cost of square meter on offshore platforms) and also it can use almost the same equipments, in continuous or batch flow, without others high costs investments. Electrochemical treatment causes low environmental impact, because the process uses electrons as reagent and generates small amount of wastes. In this work, it was studied two types of electrochemical reactors: eletroflocculation and eletroflotation, with the aim of removing of Cu2+, Zn2+, phenol and BTEX mixture of produced water. In eletroflocculation, an electrical potential was applied to an aqueous solution containing NaCl. For this, it was used iron electrodes, which promote the dissolution of metal ions, generating Fe2+ and gases which, in appropriate pH, promote also clotting-flocculation reactions, removing Cu2+ and Zn2+. In eletroflotation, a carbon steel cathode and a DSA type anode (Ti/TiO2-RuO2-SnO2) were used in a NaCl solution. It was applied an electrical current, producing strong oxidant agents as Cl2 and HOCl, increasing the degradation rate of BTEX and phenol. Under different flow rates, the Zn2+ was removed by electrodeposition or by ZnOH formation, due the increasing of pH during the reaction. To better understand the electrochemical process, a statistical protocol factor (22) with central point was conducted to analyze the sensitivity of operating parameters on removing Zn2+ by eletroflotation, confirming that the current density affected the process negatively and the flow rate positively. For economical viability of these two electrochemical treatments, the energy consumption was calculated, taking in account the kWh given by ANEEL. The treatment cost obtained were quite attractive in comparison with the current treatments used in Rio Grande do Norte state. In addition, it could still be reduced for the case of using other alternative energy source such as solar, wind or gas generated directly from the Petrochemical Plant or offshore platforms

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The resistance of aluminum and their alloys, to the corrosion phenomenon, in aqueous solutions, is a result of the oxide layer formed. However, the corrosion process in the aluminum alloy is associated with the presence a second phase of particles or the presence of chloride ions which promote the disruption of the oxide layer located producing the corrosion process. On the other hand, the term water produced is used to describe the water after the separation of the oil and gas in API separators. The volumes of produced water arrive around 5 more times to the volume of oil produced. The greatest feature of the water is the presence of numerous pollutants. Due to the increased volume of waste around the world in the current decade, the outcome and the effect of the discharge of produced water on the environment has recently become an important issue of environmental concern where numerous treatments are aimed at reducing these contaminants before disposal. Then, this study aims to investigate the electrochemical corrosion behavior of aluminum alloy 6060 in presence of water produced and the influence of organic components as well as chloride ions, by using the electrochemical techniques of linear polarization. The modification of the passive layer and the likely breakpoints were observed by atomic force microscopy (AFM). In the pit formation potential around -0.4 to -0.8 V/EAg/AgCl was observed that the diffusion of chloride ions occurs via the layer formed with the probable formation of pits. Whereas, at temperatures above 65 °C, it was observed that the range of potential for thepit formation was -0.4 to -0.5 V/EAg/AgCl. In all reactions, the concentration of Al(OH)3 in the form of a gel was observed

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Technetium-99m (99mTc) has been used to obtain several radiobiocomplexes utilized to aid in the diagnosis of diseases. Blood constituents, as red blood cells (RBC) and plasma proteins, have been labeled with 99mTc. Natural and synthetic drugs can alter the labeling of these constituents. The aim of this work was to investigate the possibility of a Buzhong YiQi Wan extract to alter (i) the labeling of blood constituents with 99mTc, (ii) the RBC morphology, and (iii) osmotic fragility of RBC withdrawn from Wistar rats. The data showed that the BYQW extract (i) could affect labeling of blood constituintes with 99mTc, (ii) could affect the membrane integrity decreasing the osmotic resistance and (iii) could not alter the shape of RBC. Probably, these findings would be associated with properties of the substances present in the aqueous extract of BYQW. This study has multiple disciplinary aspects in knowledge areas: Radiobiology, Botanic, Phytotherapy and Haematology

Relevância:

10.00% 10.00%

Publicador:

Resumo:

To aureus α-HL channel, we used the cysteine-scanning mutagenesis technique. Twenty-four mutants were produced from the substitution of a single aminoacid of the primary structure of the α-HL pro this yzed after the incorporation of a mutant channel in planar lipid bilayer membranes. The modified proteins were studied in the absence and presence of watersoluble specific sulphydryl-specific reagents, in order to introduce a strong positive or negative harge at positions of substitution. The introduction of a negative charge in the stem region onverted the selectivity of the channel from weak anionic to more cationic. However, the troduction of a positive charge increased its selectivity to the anion. The degree of these alterations was inversely dependent on the channel radius at the position of the introduced harge (selectivity). As to the asymmetry of the conductance-voltage, the influence of the harge was more complex. The introduction of the negative charge in the stem region (the trans art of the pore) provoked a decrease. The intensity of these alterations depended on the radius, and on the type of free charge at the pore entrance. These results suggest that the free charge at surrounds the pore wall is responsible for the cation-anion selectivity of the channel. The istribution of the charges between the entrances is crucial for determining the asymmetry of e conductance-voltage curves. We hope that these results serve as a model for studies with other nanometric channels, in biological or planar lipid bilayer membranes or in iotechnological applications

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Bacterial cellulose (BC) has a wide range of potential applications, namely as temporary substitute skin in the treatment of skin wounds, such as burns, ulcers and grafts. Surface properties determine the functional response of cells, an important factor for the successful development of biomaterials. This work evaluates the influence of bacterial cellulose surface treatment by plasma (BCP) on the cellular behavior and its genotoxicity potential. The modified surface was produced by plasma discharge in N2 and O2 atmosphere, and the roughness produced by ion bombardment characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Cell adhesion, viability and proliferation on BCP were analysed using crystal violet staining and the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium (MTT) method. Genotoxicity was evaluated using the comet and cytokinesis block micronucleus assay. The results show that the plasma treatment changed surface roughness, producing an ideal cell attachment, evidenced by more elongated cell morphology and improved proliferation. The excellent biocompatibility of BCP was confirmed by genotoxicity tests, which showed no significant DNA damage. The BCP has therefore great potential as a new artificial implant

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Effects of a Cordia salicifolia (porangaba) extract on the labeling of blood cells (BCs) with technetium-99m ((99m)Tc) and on the morphology of red BCs were evaluated. Labeling of cellular and molecular structures with (99m)Tc depends on a reducing agent. Some physical characteristics, as visible absorbance spectrum, electric conductivity, and refractive index of this porangaba extract, were also determined. Blood samples from Wistar rats were incubated with porangaba extract or with 0.9% NaCl (control). Labeling of blood constituents with (99m)Tc was performed. Plasma (P) and BCs, both soluble (SF-P and SF-BC) and insoluble (IF-P and IF-BC) fractions, were separated. The radioactivity in each fraction was counted, and the percentage of radioactivity incorporated (%ATI) was calculated. Blood smears were prepared, fixed, and stained, and the morphology of the red BCs was evaluated. Data showed an absorbance peak at 480 nm and electric conductibility and refractive index concentration-dependent. Porangaba extract decreased significantly (P < .05) the BC, IF-P, and IF-BC %ATI, and no modifications were verified on the shape of red BCs. Analysis of the results reveals that some physical parameters could be useful to aid in characterizing the extract studied. Moreover, it is possible that chemical compounds of this extract could have chelating/redox actions or be capable of binding to plasma and/or cellular proteins

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Uma grande quantidade de informações dá suporte à relação existente entre inatividade física e processos inflamatórios latentes em distúrbios metabólicos. O objetivo deste trabalho foi acessar criticamente o corpo de evidências existentes na literatura sobre a associação entre programas de exercícios físicos e os níveis de biomarcadores inflamatórios em mulheres entre 18 e 82 anos de idade. Foram realizadas buscas bibliográficas sistemáticas usando as bases de dados PubMed Medline, Cochrane Central Register of Controlled Trials, Web of Science, LILACS e SciELO de publicações entre janeiro de 1993 e janeiro de 2012 usando os seguintes termos: inflamação, citocinas, exercícios, treinamento físico, treinamento aeróbico, treinamento cardiovascular, treinamento de força, treinamento contra resistência, treinamento intervalado, reabilitação cardíaca e gerenciamento/modificação terapêutica de estilo de vida. Do total de estudos incluídos na revisão, três deles reportaram mudanças não significativas nos níveis de biomarcadores inflamatórios, um estudo documentou um aumento nos biomarcadores e 12 estudos reportaram decréscimos nos níveis de biomarcadores inflamatórios associados com exercício. Características secundárias do estilo de vida, como trabalho físico extenuante e fumo, afetaram os níveis de biomarcadores inflamatórios. Intervenções integrativas incluindo dieta, exercício aeróbico moderado (60% a 80% da frequência cardíaca máxima ou 50% a 60% do VO2Máx), treinamento contra resistência em circuito (8 a 10 exercícios, 8 a 12 repetições), aconselhamento e educação voltados para a saúde, usados conjuntamente, se apresentaram como possíveis estratégias efetivas na melhoria nos níveis de biomarcadores inflamatórios em mulheres

Relevância:

10.00% 10.00%

Publicador:

Resumo:

As florestas secundárias e plantações de espécies exóticas estão se expandindo nas paisagens tropicais. No entanto, nossa compreensão sobre o valor destas florestas para a conservação da biodiversidade de invertebrados ainda é incipiente. Neste trabalho, usamos a fauna de formigas de serapilheira para avaliar a diversidade desses insetos entre três florestas de Eucalyptus, sendo uma comercial (quatro anos de idade) e duas abandonadas em diferentes idades de regeneração (16 e 31 anos) e uma área de Mata Atlântica secundária. A riqueza total foi mais alta na floresta secundária e nos plantios de Eucalyptus abandonados há mais tempo. A densidade de espécies na floresta secundária foi significativamente maior quando comparado as plantações de Eucalyptus, mas não difere entre eucaliptais; análise de ordenação revelou diferenças na composição de espécies entre as plantações de Eucalyptus com subbosque ausente e com subbosque desenvolvido ou em desenvolvimento. Ainda, foi constatada uma sobreposição acentuada entre amostras de serapilheira das florestas de eucaliptos abandonadas há mais tempo e a floresta secundária. em geral, plantações de eucalipto foram caracterizadas pela presença de espécies generalistas e de ampla distribuição. Nossos resultados indicam que embora o subbosque de plantações de eucaliptos com maior idade de regeneração suporte um conjunto relativamente alto de espécies generalistas de formigas, é improvável que eucaliptais conservem a maioria das espécies de florestas primárias, especialmente predadores especializados, Dacetini e espécies nômades.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coeficientes de correlações genéticas e fenotípicas foram estimados entre os caracteres: altura da planta (AP); altura da espiga (AE); peso de espigas (PE) e teor de óleo (TO). As estimativas foram obtidas para duas populações braquíticas de milho (Piranão VD-2 e Piranão VF-1), baseado em espiga por fileira, utilizando-se testemunha intercalar, onde a cada duas progênies plantava-se uma fileira do híbrido simples AG 305-B. Os valores das correlações genéticas aditivas encontradas entre os caracteres altura da planta, altura da espiga e peso de espigas, foram todos positivos. Para o caráter teor de óleo, quando correlacionado com os demais caracteres, os valores das correlações obtidos foram negativos nas duas populações, exceção feita ao peso de espiga correlacionada com teor de óleo, na população Piranão VD-2, cujo valor foi positivo e próximo de zero. As respostas correlacionadas obtidas entre os caracteres, quando a seleção é praticada para o caráter teor de óleo e vice versa, independente do método de seleção empregado, mostram que a seleção para teor de óleo leva a modificação na estrutura da planta, para as duas populações.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

O preparo do solo é um dos processos que aceleram a decomposição da matéria orgânica, transferindo carbono para atmosfera, principalmente na forma de CO2. Neste trabalho, investigou-se o efeito do preparo com enxada rotativa sobre as emissões de CO2 do solo durante 02 semanas após o preparo do solo, incluindo-se a presença de resíduos vegetais sobre a superfície. As emissões foram avaliadas por 15 dias após preparo em 3 parcelas: 1) sem preparo e sem palha superficial (SPs); 2) preparo com enxada rotativa sem a presença de palha na superfície (ERs), e 3) preparo com enxada rotativa com a presença de palha superficial (ERc). As emissões provenientes da ERc foram superiores às demais (0,777 g CO2 m-2 h-1), sendo as menores emissões registradas na parcela SPs (0,414 g CO2 m-2 h-1). As emissões totais indicaram que a diferença de C-CO2 emitida à atmosfera corresponde a 3% do total de carbono adicional presente na palha, na parcela ERc, quando comparado à parcela ERs. O aumento da emissão da parcela SPs para ERs foi acompanhado de uma modificação na distribuição do tamanho de agregados, especialmente aqueles com diâmetro médio inferior a 2 mm. O aumento da emissão da parcela ERs para ERc esteve relacionado a uma diminuição da massa de palha na superfície, com fragmentação e incorporação da mesma no interior do solo. Quando se analisa a correlação linear entre emissão de CO2 versus temperatura e umidade do solo, somente a emissão da ERc foi significativamente correlacionada (p<0,05) à umidade do solo.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

As can be inferred by the title of its study The constitutional principle of sustainable development and the utilization of hidrical resources in the oil industry the transcribed pages are dedicated to the approach of the mentioned subjects which, despite being apparently different, will be shown intrinsically connected as goes by the study. The superation of this first step by the reader will lead to an important perception of the title: that the situation requires, urgently, a defined posture, a complete conduct change and, therefore, a modification of the paradigms currently establisheds. To brake barriers, modifying what is lived by, is the ultimate goal. For that, there is no unique path, linear, but there were broached the development themes, the hidrical resources theme and oil and natural gas industry at the necessary points to achieve, by the end, a comprehension for the Brazilian Federal Republic goals in the search for the application of these juridical norms. The ones whom lay down over this study shall notice that, more than a simple approach over these themes (which are still less worked and searched in Brazil), the heavy critic of an instituted and pacifically accepted reality, directly offensive of the constitutional principles. The debate evolves from punctual and specific aspects, it gains life, flies, searching how the juridical order equalizes the economic model to the environment defense. Standing by the possibility of conciliation among constitutional principles, the remodeling of an economic segment is defended, aligning it to the sustainable limits. Development, sustainable, becomes means and goals to the implementation of liberty, capacitating everyone to achieve their goals of life, their libertments, fruit of the inherent antagonism of the Constitution the sustainable development offers, while an axiological vector, a new reality to the economic order, turning it into a motriz element to the fortification of constitutional normative force and for the national development

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Under the circumstances of the desestatization that penetrate Brazilian economy in the 90‟s, new features in the monopoly of oil by the Union were designed by the constitutional amendment number 9. of 1995. This deep change in the legal regime of oil sector brought the possibility of entrance to small and medium size producers in this industry, especially through the production activities developed in mature and marginal fields of oil, which are located mainly in northeast region of Brazil. Considering that the intervention of state over the economy finds its guidelines and limits in Federal Constitution disposals, the present work investigated in which way states regulation, mainly through taxation rules, has obeyed the constitutional regime in force, and specially, the reduction of regional inequalities principle. By mean, firstly, of an analysis of central concepts (mature fields, marginal fields, small and medium size producers) we observed that the imprecision over the conceptual aspect has constituted an obstacle to a specific states‟ regulation, directed to this newborn class of producers, whose growth has been pursuit by the state. That is verified in the case of concession procedures, and also, concerning the taxation system applied to small and medium size producers. Examining the main constitutional principles related to this universe which are the legality, equality, privileged treatment to small enterprises, contributive capacity, and reduction of regional inequalities we conclude that it is legally possible, a truly specific regulation, including a special taxation regime, to the small and medium size producers whose activities are concentrate over mature-marginal fields, aiming the concretization of the Brazilian state main goals

Relevância:

10.00% 10.00%

Publicador:

Resumo:

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

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The main goal of this work is to verify the presence of the principle of human dignity, determined by the Constitution of 1988, when Socio Educational Acts from the Statute of Children and adolescent were put in practice, focusing on the treatment designated to the youth whose acts were against the law in the city of Natal, as well as the difficulties to match the legal texts and its reality. It is common knowledge that the law for children and adolescent was based in the principle of human dignity, for its institutes say so. But would the Law match the practice of Socio Educational Acts? Or this law would be an example of good intentions that never left the paper and became reality? First there is an approach on the human dignity principle, with its definition and limitation, according to a theory about the theme. Afterwards it is made a connection between human rights and the principle of human dignity considering historical and social features, for the law is also a reflect of these transformations, we try to show the different laws the country had until today, concerning the children inflicted by poverty and those whose acts were against the law, since the rodas dos expostos, the phase of irregular situation, in which the children were arrested simply because they were beggars, until present time. The theory aspects are shown beside a field research made with the adolescent and staff from CEDUC/Natal, producing a critical view about the subject and showing some solutions for the problems found. At last, it is made a critical analyses of the problems detected on the field research, and, in some cases, a suggestion is given to change the reality

Relevância:

10.00% 10.00%

Publicador:

Resumo:

As an effect of the growing interdependence in international relations, regional integration was conceived to face globalization, with a remarkable influence in politics and law, since the first steps of the European experience. In Latin America, regional integration ideas have blossomed in the 60 s. Among its experiences, MERCOSUL is the one with the most advanced objectives. However, MERCOSUL has not managed to achieve the objectives planned nor moved forward the integration process. Differently of what happened in Europe, in MERCOSUL the common market projected is concluded. It faced many disappointments throughout its brief history. As it matters to law, those were caused by the absence of supranationality, a mechanism that would allow MERCOSUL s decisions to be directly binding in the States with no need of bureaucratic proceedings to incorporate them to national legal systems. Among Latin American States, Brazil is probably the most resistant to integration process, due to Federal Constitution 1988 rigidity and legal professionals conservadorism towards opening legal system to international law. In Brazil hermeneutical standards are always based on national sovereignty and international law is referred as less important. The problems become more visible relating to taxation, a subject that plays an enormous role in integration process for its economic impact, demanding the execution of tax harmonization policies compatible to the integration levels aspired. However, because of the large number of tax rules in the Federal Constitution, structural changes initiatives face difficulties in order to be implemented. Actually, after two Constitutional Reforms on taxation, Brazil has not yet succeeded on promoting the necessary adaptations to regional integration. The research has confirmed the hypothesis that supranationality has indispensably to be adopted if Brazil really desires to move forward the integration process. But it has also been demonstrated that there are hermeneutical paths suitable to the constitutional profile which allow the adoption of supranationality, through the revision of the sovereignty traditional concept