114 resultados para Analise por diluição isotopica
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Cashew-nut-shell-liquid (CNSL) is a phenolic oil that hás been due its their antioxirsion properties for use in fuels. The present work develops a method to the conversion of hidrogenated cardanol, that is the main component of the CNSL, in a compound with similar chacteristics to antioxidants used in products from petroleum. The antioxidants wasd obtained by exhaustive alkylation of the compound with tert-butyl chloride. After completing the optimization of several reaction steps, the product 2,4,6 tri-tert-butyl (pentadecylphenol) was obtained for the first tima. Characteeization and determination of physico-chemical properties were realized too, as well as wasd developed a study for check your application as an oxidative inhibitor by the molecular modeling. Estimation of process evalution was executed as well, where a rapid and practical computational methodology was utilizated in projects of the fine chemistry. The research showed satisfactory results and it could be concluded that the commercialization of this chemical products is feasible
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This work presents the incorporation of an industrial polymeric waste into a petroleum asphalt cement with penetration grade 50-60 (CAP 50-60). The main goal of this research is the development of a polymer-modified asphalt, with improvements in its physical properties, in order to obtain a more resistant material to the traffic loads. Furthermore, the use of this polymeric waste will result in economic and environmental benefits. The CAP 50-60 used in this research was kindly supplied by LUBNOR Lubrificantes e Derivados de Petróleo do Nordeste (produced in Fazenda Belém Aracati - Ceará) and the industrial polymeric waste was provided by a button manufacturer industry, located in Rio Grande do Norte state. This polymeric waste represents an environmental problem due to its difficulty in recycling and disposal, being necessary the payment by the industry to a landfill. The difficulty in its reuse is for being this material a termofixed polymer, as a result, the button chips resulting from the molding process cannot be employed for the same purpose. The first step in this research was the characterization of the polymeric waste, using Differential Scanning Calorimetry (DSC) Infrared spectroscopy (IR spectroscopy), and Thermogravimetric analysis (TGA). Based on the results, the material was classified as unsaturated polyester. After, laboratory experiments were accomplished seeking to incorporate the polymeric waste into the asphalt binder according to a 23 experimental factorial design, using as main factors: the polymer content (2%, 7% and 14%), the temperature of the mixture (140 and 180 oC) and the reaction time (20 and 60 minutes). The characterization of the polymer-modified asphalt was accomplished by traditional tests, such as: penetration, ring and ball softening point, viscosity, ductility and flash point temperature. The obtained results demonstrated that the addition of the polymeric waste into the asphalt binder modified some of its physical properties. However, this addition can be considered as a feasible alternative for the use of the polymeric waste, which is a serious environmental and technological problem.
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Biosurfactants are amphiphilic molecules synthesized by microorganisms such as bacteria, yeast or filamented fungi cultivated in various carbon sources among sucrose and hydrocarbons. These molecules are composed by a hydrophilic and hydrophobic part. They operate mostly at interfaces of fluids of different polarities. Because of this characteristic, they are potentially employed in numerous industries, such as the textile, medical, cosmetics, food and mainly in the petrochemical ones. Therefore industry has interest in developing new biosurfactant production processes in high scale, in order to become them economically competitive when compared to synthetic biosurfactants. This work aims to evaluate the biosurfactant production applying a non-conventional substrate sugar cane molasses proceeding from the sugar industry thus reducing the production costs. The strain identified as AP029/GLIIA, isolated from oil wells in Rio Grande do Norte state and used in these experiments belongs to the culture collection of Antibiotics Department of UFPE. The fermentation were carried out using different conditions according to a factorial planning 24 with duplicate at center point, in which the studied factors were molasse concentration, nitrate concentration, agitation and aeration ratio. The experiments were performed in a shaker at 38ºC of temperature. Samples were withdrawn in regular periods of time of up to 72 hours of fermentation in order to analyze substrate consumption, cellular concentration, superficial tension, critical micelle dilution (CMD-1 e CMD-2) as well as extracelullar protein production. The results showed a production of 3,480 g/L of biomass, a reduction of 41% on superficial tension, 67% of substrate consumption and 0,2805 g/L of extracellular protein
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Discussions about pollution caused by vehicles emission are old and have been developed along the years. The search for cleaner technologies and frequent weather alterations have been inducing industries and government organizations to impose limits much more rigorous to the contaminant content in fuels, which have an direct impact in atmospheric emissions. Nowadays, the quality of fuels, in relation to the sulfur content, is carried out through the process of hydrodesulfurization. Adsorption processes also represent an interesting alternative route to the removal of sulfur content. Both processes are simpler and operate to atmospheric temperatures and pressures. This work studies the synthesis and characterization of aluminophosphate impregnate with zinc, molybdenum or both, and its application in the sulfur removal from the gasoline through the adsorption process, using a pattern gasoline containing isooctane and thiophene. The adsorbents were characterized by x-ray diffraction, differential thermal analysis (DTG), x-ray fluorescence and scanning electron microscopy (SEM). The specific area, volume and pore diameter were determined by BET (Brunauer- Emmet-Teller) and the t-plot method. The sulfur was quantified by elementary analysis using ANTEK 9000 NS. The adsorption process was evaluated as function of the temperature variation and initial sulfur content through the adsorption isotherm and its thermodynamic parameters. The parameters of entropy (ΔS), enthalpy variation (ΔH) and free Gibbs energy (ΔG) were calculated through the graph ln(Kd) versus 1/T. Langmuir, Freundlich and Langmuir-Freundlich models were adjusted to the experimental data, and the last one had presented better results. The thermodynamic tests were accomplished in different temperatures, such as 30, 40 and 50ºC, where it was concluded the adsorption process is spontaneous and exothermic. The kinetic of adsorption was studied by 24 h and it showed that the capability adsorption to the adsorbents studied respect the following order: MoZnPO > MoPO > ZnPO > AlPO. The maximum adsorption capacity was 4.91 mg/g for MoZnPO with an adsorption efficiency of 49%.
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The green bean has organoleptic and nutritional characteristics that make it an important food source in tropical regions such as the Northeast of Brazil. It is a cheap source of protein and important for nutrition of rural population contributing significantly in subsistence farming of the families from Brazil s northeast. It is consumed in entire region and together with the dry meat and other products composes the menu of typical restaurants, being characterized as an important product for economy of Northeast. The green bean is consumed freshly harvested and has short cycle, being characterized as a very perishable food, which hampers your market. The drying method is an alternative to increase the lifetime and provide a reduction volume of this product making easier your transportation and storage. However is necessary to search ways of drying which keep the product quality not only from the nutritional standpoint but also organoleptic. Some characteristics may change with the drying process such as the coloring, the rehydration capacity and the grains cooking time. The decrease of drying time or of exposure of the grains to high temperature minimizes the effects related with the product quality loss. Among the techniques used to reduce the drying time and improve some characteristics of the product, stands out the osmotic dehydration, widely used in combined processes such as the pretreatment in drying food. Currently the use of the microwaves has been considered an alternative for drying food. The microwave energy generates heat inside of materials processed and the heating is practically instantaneous, resulting in shorter processing times and product quality higher to that obtained by conventional methods. Considering the importance of the green beans for the Northeast region, the wastefulness of production due to seasonality of the crop and your high perishability, the proposal of this thesis is the study of drying grain by microwaves with and without osmotic pretreatment, focusing on the search of conditions of processes which favor the rehydration of the product preserving your organoleptic characteristics. Based on the analysis of the results of osmotic dehydration and dielectric properties was defined the operating condition to be used in pretreatment of the green bean, with osmotic concentration in saline solution containing 12,5% of sodium chloride, at 40°C for 20 minutes. The drying of green bean by microwave was performed with and without osmotic pretreatment on the optimized condition. The osmotic predehydration favored the additional drying, reducing the process time. The rehydration of dehydrated green bean with and without osmotic pretreatment was accomplished in different temperature conditions and immersion time according to a factorial design 22, with 3 repetitions at the central point. According to results the better condition was obtained with the osmotically pretreated bean and rehydrated at a temperature of 60°C for 90 minutes. Sensory analysis was performed comparing the sample of the green bean in natura and rehydrated in optimized conditions, with and without osmotic pretreatment. All samples showed a good acceptance rate regarding the analyzed attributes (appearance, texture, color, odor and taste), with all values above 70%. Is possible conclude that the drying of green bean by microwave with osmotic pretreatment is feasible both in respect to technical aspects and rehydration rates and sensory quality of the product
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The Pitimbu River Basin is concern reason, therefore this is one of the mains freshwater sources for the Natal city supplying. The Pitimbu waters river flow into Jiqui pond, as the main supplier of this, that supplies 16% of Natal population and there is a bigger importance despite the supplying of a parcel of Natal city made joining underground waters with the water proceeding from the Jiqui pond, being used for dilution waters of contaminated wells with nitrate. Even with the importance of the Pitimbu, there is a strong pressure of occupation of its edge according to a critical urban growth, becoming the situation worse and increasing the necessity of management of the use and occupation of the ground and keeping the control of the prompt pollution, as punctual as diffuse. There are many studies about Pitimbu River Basin, however they summarize themselves to some months or even in a few years. This work, that gathers these information, increasing the amplitude and making possible an evaluation of the attitude of the water in a period extended for an evaluation of values of variable quality of water referring to the standards, that usually happens about the variable frequency distribution, central tendency and measures of dispersion, as the coefficient of variation, coefficient of skewness and the coefficient of determination of certain variable on another one. This work to evaluates the quality conditions of the Pitimbu river waters by analyzing thirty five (35) variables Physical, chemical and biological in eight (8) points of water course since 1993 to 2007. Given this situation, all knowledge about the waters quality conditions obtained in this work, is a strong subsidy for management of use and ground occupation, considering the river basin as territorial unit of management, and as the water is public good domain, being a priority human use, It is necessary to guarantee to current and the future generations available water resources in appropriate standards of quality as the established standard and identifying possible reasons of pollution through statistics analysis
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Urban growth of metropolitan areas has produced impacts of considerable importance on environment and water resources. Such impacts are in general associated with human activities, such as basin area uncontrolled development. In this context, Pitimbu river watershed, located at Natal metropolitan area, has been affected by uncontrolled development caused by urban expansion. Indeed, such effects have been reflected on water quantity and quality, which may produce social consequences. Pitimbu river is an important water supplier for human consumption, actually supplying a 2600 m3/h water discharge. This study aims to analyze the qualitative and quantitative aspects of water and sediment on Pitimbu river lowland portion. For this purpose, physical-chemical water properties were analyzed, and sediment macro invertebrates benthonic were monitored in two cross sections in a period between November 8th, 2007 and October 3rd, 2008. Monitoring methodology consisted of water and sediment sampling for laboratory analysis. Water quality analysis included Dissolved Oxygen, Oxygen Biochemical Demand, Nitrate, pH and Alkalinity, Suspended and Total Solids. The analysis of heavy metals in the sediment included Cadmium, Cobalt, Copper, Chrome, Silver and Nickel. Dry season water discharge data were measured and used to adjust recession function parameters, whose values reveal quick recession and strong river-aquifer unconfined interaction. Water quality analysis revealed the absence of degradation by organic composites. However, DO and BOD levels indicate that more consistent results could be provided if sampling time interval were reduced. Biomonitoring showed signs of aquatic ecosystem degradation by the absence of sensitive and abundance of resistant benthic organisms. Obtained results demonstrate the urgent need of effective management measures to provide environmental protection. The increase of environmental degradation will certainly make impracticable the use of water for human consumption
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The study that resulted in this dissertation was developed at OU RNCE PETROBRAS, in Natal, which implemented a project of rational use and reuse of water, including use of wastewater from a Sewage Treatment Plant (STP) already in place, diluted with water from own wells for irrigation of green area of the building complex corporate enterprise. Establish a methodology that can serve as guidelines for future projects controlled reuse of water like this was the objective of this research. Been proposed, implemented and evaluated three instruments of sanitary and environmental control: 1) adaptation of sewage treatment plant and quality control of the treated effluent 2) analysis of soil-nutrient interaction in the irrigated area, 3) knowledge of the local hydrogeology, especially with regard to the direction of flow of the aquifer and location of collection wells of Companhia de Águas e Esgotos do Rio Grande do Norte (CAERN) situated in the surroundings. These instruments have proven sufficient and appropriate to ensure the levels of sanitary and environmental control proposed and studied, which were: a) control of water quality off the STP and the output of the irrigation reservoir, b) control of water quality sub surface soil and assessment of progress on soil composition, c) assessment of water quality in the aquifer. For this, we must: 1) establishing the monitoring plan of the STP and its effluent quality sampling points and defining the parameters of analysis, improve the functioning of that identifying the adequacy of flow and screening as the main factors of operational control, and increase the efficiency of the station to a relatively low cost, using additional filters, 2) propose, implement and adapt simple collectors to assess the quality of water percolating into the soil of the irrigated area, 3) determine the direction of groundwater flow in the area study and select the wells for monitoring of the aquifer.
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The growing accumulation of people in urban centers caused chronic problems of the cities to begin to take an increasingly unsustainable. Primarily related to lack of infrastructure coupled with sanitation and lack of investment in critical sectors such as health, education, housing and transportation, these problems start to deteriorate markedly the quality of life of city dwellers and put into test management policies of the spaces urbanized. To reverse this situation, shows is essential to the use of tools (highlighting this harvest rates and environmental indicators) that help in assessing the current conditions and may assist in predicting future scenarios. From the information listed above, now put the research seeks to present an index called ISBA Environmental (Sanitation Index) which looks at the four urban systems (water, sewer, solid waste and urban drainage) from the viewpoint of application in a geographical cutout specific - in this case the Drainage Basin XII, defined by the Plan of Urban Drainage Stormwater in the city of Natal, capital of Rio Grande do Norte. This index, together with analysis of other factors sought to trace the current conditions of the basin and thus, assist in proposing the best solutions. For the preparation of the index was applied a questionnaire with a sample of 384 (three hundred eighty-four) households that aimed to study two variables: access to services and satisfaction of the population in relation to these. The ISBA has shown that the system is the most deficient collection and disposal of effluents (ICE = 47.66%), followed by the drainage of rainwater (IDAP = 54.17%), water supply (AAI = 61, 36) and solid waste collection (IRS = 78.28). With the ISBA was possible to verify that the qualitative data shows whose subjectivity is evident (as is the case of user satisfaction) can be of great importance when an assessment, since we obtained the correlation coefficient between the variables "Access" and " Satisfaction "equal to 0.8234, showing a strong correlation between the existence / quality of service offered and the impressions of the population that receives them
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O presente trabalho consiste em uma investigação acerca das concepções de estudantes sobre o que é um inseto. Partiu-se do pressuposto de que os alunos expressam concepções errôneas no momento de identificar os representantes do táxon Insecta e que isso é consequência das experiências do cotidiano e de erros conceituais oriundos da formação escolar incorreta. Os objetivos deste trabalho foram investigar sobre concepções alternativas acerca dos insetos com alunos do ensino fundamental II e propor situações para promoção de uma aprendizagem mais ativa. Os dados para analise foram coletados em três turmas de escolas diferentes: uma escola em Nova Parnamirim, da rede privada, e duas da rede pública municipal de ensino: uma do município de Natal/RN e a outra do município de Parnamirim/RN. Utilizou-se como instrumento um questionário aplicado em duas fases. Na primeira etapa foram feitas três questões abertas e duas fechadas. Na segunda, aplicaram-se mais três questões. Nesta oportunidade foram apresentados aos alunos uma lista com imagens de insetos e animais considerados não insetos. Os resultados dos questionários mostraram que os alunos apresentaram na sua maioria, 62%, sentimentos negativos sobre os insetos, expressos por palavras depreciativas, entre elas: nojentos, feios, asquerosos, perigosos, sendo estes mais da metade dos alunos da amostra. Sentimentos positivos representaram 20%: fazem bem ao homem, Deus criou, são bons, são bonitos, e 18% apresentaram neutralidade nessas categorias. Outro resultado apresentado foi que 82% generalizaram os animais artrópodes como sendo insetos. Como forma de resolver problemas relacionados as concepções uma unidade didática foi aplicada em uma das escolas envolvidas na pesquisa, validando assim um instrumento pedagógico que incluiu atividade lúdica constituída de um jogo de tabuleiro proporcionador de uma vivência de aprendizagem focada em conceitos científicos sobre os insetos fáceis de serem apreendidos
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A disciplina Física do Meio Ambiente (FMA) foi criada em 1976 no Departamento de Física Teórica e Experimental da UFRN e, atualmente, faz parte da estrutura curricular do curso de Licenciatura em Física da UFRN e é de caráter obrigatório. Tal caráter se justifica, dentre outros motivos, pelo fato de que esta disciplina representa uma boa oportunidade dos licenciandos estudarem de que forma a Física pode contribuir para a compreensão de fenômenos relativos ao nosso Meio Ambiente, sejam eles relacionados às atividades humanas ou aos fenômenos naturais propriamente ditos e que, de uma forma ou de outra, afeta a sociedade. O nosso trabalho de pesquisa teve como objetivo principal elaborar um novo programa de ensino para a disciplina de Física do Meio Ambiente adequado às necessidades da educação científica para o século XXI. A pesquisa foi conduzida inicialmente com um levantamento histórico da disciplina desde sua origem no Departamento de Física ate os dias atuais, analise dos Projetos Pedagógicos do curso de Licenciatura em Física da UFRN, revisão bibliográfica sobre as definições de competências e habilidades em um contexto de ensino e segundo o pensamento de vanguarda nesse campo de pesquisa, acompanhamento do curso durante um semestre através de aulas observacionais, aplicação de questionário para a coleta de dados e análise de alguns livros didáticos de Física do Ensino Médio. A partir do perfil ou modelo profissional para o licenciado em Física da UFRN definimos os objetivos gerais para a disciplina de FMA em termos de habilidades gerais relacionadas com as atividades que um futuro professor de Física irá desempenhar no seu dia a dia. O nosso programa de ensino foi pensado no sentido de introduzir conteúdos de didática específica ao longo da disciplina, isto é, familiarizar os professores em formação com investigação e inovação didáticas voltadas para o ensino de temas que envolvam a conexão entre Física e Meio Ambiente. Como resultado de nossa pesquisa foi proposto um novo Programa de Ensino para FMA que pode ser útil aos futuros professores desta disciplina e foi elaborado segundo uma metodologia de organização científica do processo ensino
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This work has risen from the researcher s pedagogical practice at a technical school in Natal, and it aims to observ how affectiveness is noticed by the students in their English classes, since we can have an idea of technicist teaching, which foccus on the acquisition of technical abilities. As cognition and affectiveness are considered indivisible elements in this research, we tried to identify the linguistic signs that express the students representations about affectiveness in their English classes. We used the Systemic Functional Linguistics approach to study the Ideational metafunction of Halliday (1994), by means of the transitivity system, to show how the clauses are used to illustrate these representations, and the interpersonal metafunction, that deals with the relationship between the teacher and the students. We tried to identify the most common processes (HALLIDAY, 1994) mentioned by the 68 students who participated in this work. We used learning narratives (BARCELOS, 2006) submitted to Wordsmith Tools computing program (SCOTT, 2009), whose results indicate the most frequent lexical items found in their narratives. The lexical choices seem to indicate that affectiveness is noticed as a composing element of the English classes in that school. There are representations of interacting classes, where the students needs are considered. These representations are built in the relationship of the students and the teacher, and they are grammatically realized by means of the polarity adjunct no , the intensity adjunct very , and the nominal group the teacher . The relational and mental processes (be) and (like) are the most used in their narratives, and we also observe that affectiveness and disponibility to help the students are considered the most important attitudes in their representations. The Appraisal system is used to analise the choices related to the attitudes and judgement of the students, that show appreciation for interacting classes, but there is still authorithary berhavior from the teacher in the English classes
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Diese These besteht aus der Analyse der Enteignungsverhältnisse und der Misselung, welche in den Texten der Ursprung des Kunstwerkes und die Hymnen Hölderlins vorkommen. Germanien und der Rhein sind in den 30en-Jahren letzten Jahrhunderts von Martin Heidegger verfasst worden. Ab anwendung der kritischen Methodologia von Harold Bloom und der starken Texgestaltung von Richard Rorty wird es deutlich, dass die Heideggers Lesungen der Hölderlins Poesia als ei Ersatzversuch der von Hegel entwickelte Kulturgeschichte ab deutescher Überlieferung klassicher Studien, die das tragische Erlebnis der alten Griechen als grundlegender Punkt des Westen Daseins vorbringen, verstanden werden können. So verlegt Heidegger die Aufbauachse der Entstehungserzälung des Abendlandes in Richtung Dichtkunst, indem er in seiner Wendung zum Dichterischen gleichzeitig auf der Suche nach einer abweichenden Feststellung der vorherrschaftlichen These ist, in welcher die Tragödie das grosse Antrittsereignis der westlichen Zivilisation darstellt, und darüber hinaus noch der Herstellung einer innigen Verbindung zwischen der Poesie von Hölderlin und Hesiudus, um die Enge der dichterischen Überinstimmung zu zeigen, welche die alten Griechen und die zeitegemässigen Deutschen verbrände. Dieser geistige Aufbau Heideggers hat man somit als ein überholungsversuch Hegels Einfluss und Denkungsart zur Vollendung der von Nietzsche begonnenen Überwindungsaufgabe des Hegelianismus´zu verstehen
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This piece focuses on the issue of media in the contemporary context, taking for its object the sociocultural phenomenon of mediatization‟, understood as the dilution of media culture in the everyday life, according to the perspective from Fausto Neto (2008) e Sodré (2002). This phenomenon is viewed from the angle of reception, that is, one that considers the individuals as pro-actives in this dynamic. The media culture is perceived as a fundamental element in the process of social structuring, and also is taken as a symbolic arm of great importance for the elaboration of the notion of reality as it interferes with the flow of information. Thus, we emphasize the process of symbolic consumption that we do with media content (Canclini, 1999), through a dynamic of appropriation and reframing, given from the interweaving of the meanings proposed with extra-media elements, recaptured from the perspective of mediations, by Barbero (2006), which concerns the articulation of the contents we appropriate from media with interactions from other social practices. We also consider the dimension of memory according to Sarlo (2007) and Halbwachs (2004) in order to, through speeches made in its scope, reach empirically the phenomenon of mediatization‟, and overlapping it, the media consumption on a specific theme, "science". Nevertheless, in terms of field work, we use the technique of in-depth interviews, so that the speech of our interviewers was our corpus. Through their narratives, speeches considered by us as memory-related, we visualize the dynamics of media consumption on given topic. At the level of conclusions, we realize that mediatization‟ as a phenomenon occurred, but its flows and orders showed discontinuities and pluralities not initially conceived; regarding the consumption of science through media, we see hybrid perceptions by our respondents, that is, one that include both elements aligned with the positivist conception of science - which we consider to be the view of science proposed by the media and elements that would contradict this view