959 resultados para NARANJA DULCE


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In recent years, solid carriers suitable oxygen have been developed for use in different chemical processes recirculation. The success of this technology is directly related to the chemical reactivity and the oxygen storage capacity of the carrier. Thus, research into the development of new materials that can be applied to the process becomes extremely important. Possible candidates are the carriers based on nickel and copper for presenting favorable thermodynamic properties. In this work, aluminates type MAl2O4 (M = Mg and Ca) and M0,9B0,1Al2O4 (B = Ni and Cu) that are used as supports were synthesized by combustion reactions assisted by microwave and calcined at 900°C/2h. Then, the carriers were impregnated with 10% (m/m) of nickel or copper, and subsequently calcined at 600°C/2h to obtain the solid oxygen carriers, which were characterized by X-ray diffraction (XRD) Microscopy scanning electron microscopy (SEM) and temperature programmed reduction (TPR). Reactions simulating the combustion process by chemical recirculation were performed by cycles reduction/oxidation, in order to evaluate the reactivity of carriers. XRD analysis revealed diffraction peaks of the spinel type structures. In the doped substrates were verified the presence of secondary phases, suggesting that all the metal was incorporated into the spinel structure. In solid oxygen carriers, the NiO and CuO phases were observed after impregnation of active phases on different media. The results of evaluations of chemical cycles reduction/oxidation revealed that TSO's impregnated with nickel in various media were more active and are potential candidates for use in the chemical recirculation technology

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Natal has come through major changes in the last 150 years, since the actions of city beautification, in the 19th century, until the present day, when such transformations start to have the objective of including the city in the competition for the attraction of the capital flows and consumption, domestically and in a foreign sense. It is thought that the first initiatives aimed at increasing tourism in Natal occurred in the 1960s, however, it became apparent that only from the 1980s was there a significant increase in tourist activities in Natal and the Metropolitan Region, especially on the east coast of the state of Rio Grande do Norte, leading to an expansion of the labour market, the significant increase of foreign investment, territorial changes of great impact and the production of buildings primarily intended for the hotel industry and second residence for European tourists. Since then, the incentives for tourist activity in the state have been maintained and even increased, based on tourism aimed at natural beauties, local cuisine and events, which transformed the tourist activity in one of the main sources of foreign exchange for the city of Natal. In the early 21st century, the construction of high-rise condominiums, monuments (including the designer ones), such as the Parque da Cidade, designed by Oscar Niemeyer, were already established. Also, shopping centers and, in order to host the World Cup, the new football stadium, the Arena das Dunas, among others, which were aimed at local and foreign consumers, especially European, stood out in the city. It is understood that these new buildings, monuments and also renovations and restorations that were deployed in the city of Natal aimed at constructing a new identity for the city, within the process of capitalist development and urban spectacle. It is considered that the monuments and the iconic buildings are attributes of the cities aimed at selling locations as goods, establishing a new urban environment, a new role as cities, which aimed at seeking greater autonomy from the nation-state. In this research, it was sought to analyze the architectural object, that is, buildings and monuments built or restored in Natal and its relevance to the city marketing promoted by the city itself. It was found that, indeed, such buildings and monuments are inserted in contemporary architectural production as a basis for increasing the competitive nature of Natal. In addition, they reveal a capitalist mode of production, supported by public resources, operating in the production of urban space with a view to repeating the hegemonic model of a competitive city

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Compatibility testing between a drilling fluid and a cement slurry is one of the steps before an operation of cementing oil wells. This test allows us to evaluate the main effects that contamination of these two fluids may cause the technological properties of a cement paste. The interactions between cement paste and drilling fluid, because its different chemical compositions, may affect the cement hydration reactions, damaging the cementing operation. Thus, we carried out the study of the compatibility of non-aqueous drilling fluid and a cement slurry additives. The preparation procedures of the non-aqueous drilling fluid, the cement paste and completion of compatibility testing were performed as set out by the oil industry standards. In the compatibility test is evaluated rheological properties, thickening time, stability and compressive strength of cement pastes. We also conducted analyzes of scanning electron microscopy and X-ray diffraction of the mixture obtained by the compatibility test to determine the microstructural changes in cement pastes. The compatibility test showed no visual changes in the properties of the cement paste, as phase separation. However, after the addition of nonaqueous drilling fluid to cement slurry there was an increased amount of plastic viscosity, the yield point and gel strength. Among the major causative factors can include: chemical reaction of the components present in the non-aqueous drilling fluid as the primary emulsifier, wetting agent and paraffin oil, with the chemical constituents of the cement. There was a reduction in the compressive strength of the cement paste after mixing with this drilling fluid. Thickening test showed that the oil wetting agent and high salinity of the non-aqueous fluid have accelerating action of the handle of the cement paste time. The stability of the cement paste is impaired to the extent that there is increased contamination of the cement slurry with the nonaqueous fluid. The X-ray diffraction identified the formation of portlandite and calcium silicate in contaminated samples. The scanning electron microscopy confirmed the development of the identified structures in the X-ray diffraction and also found the presence of wells in the cured cement paste. The latter, formed by the emulsion stability of the drilling fluid in the cement paste, corroborate the reduction of mechanical strength. The oil wetting agent component of the non-aqueous drilling fluid, the modified cement hydration processes, mainly affecting the setting time.

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The need to preserve the environment has led to the search for new materials for efficient disposal of chemical compounds that alter the stability of our natural resources. Among these resources, stands in first place the water, as a precious commodity and scarce, leading to the proper use and reuse. As a result, the World Health Organization has established maximum permissible values in drinking water, such as: 50 mg/L, 0, 1 mg/L and 0, 5 mg/L to at-3, at-2, NH 4, respectively. For these reasons, assesses the implementation of new materials and water treatment processes aiming at the removal of these compounds, such as alumina, in the form of powder or as a support for a catalytic system using inorganic membranes capable of supporting more severe conditions of temperature and pressure by opening new possibilities for applications of membrane reactors; and also for electrochemical treatments with doped diamond bobo electrodes (BDD) as anode and copper as cathode. For such purpose, was conducted the study of adsorption of nitrate in different times to assess the time required to achieve equilibrium by employing three commercial alumina called: acidic, basic and neutral alumina, with subsequent treatment only in the acidic alumina impregnating metals (PdCu/Al2O3) for the catalytic reaction. The materials were previously characterized by XRD, SEM techniques and ABET. Aluminas presented a considerable adsortive capacity of nitrate in the first thirty minutes, equivalent to 50% of removal reaching equilibrium in that time. After treatment, using alumina as catalyst for the reaction in batch reactor (Pd-Cu/Al2O3), the results were more favourable, totalling 64% reduction of ion NO3-at the end of three hours. On the other hand, the results for the catalytic reaction using the catalytic support Pd-Cu/TiO2 in membrane reactor proved to be low. -if, in this way, improve the conditions of catalytic system to optimize the process. Already, for the electrochemical tests using DDB1 electrodes as anode, and Cu, as cathode, there was a fairly significant nitrate reduction, approximately 80% of ion removal during three hours and cost viable applications.

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Increasing energy demand is being met largely by fossil fuel reserves, which emit CO2, SOx gases and various other pollutants. So does the search for fuels that emit fewer pollutants and have the same energy efficiency. In this context, hydrogen (H2) has been increasingly recognized as a potential carrier of energy for the near future. This is because the H2 can be obtained by different routes and has a wide application area , in addition to having clean burning, generating only H2O as a product of combustion , and higher energy density per unit mass . The Chemical Looping Reforming process (CLR) has been extensively investigated in recent years, it is possible to regenerate the catalyst by applying cycles of reduction and oxidation. This work has as main objective to develop catalysts based on nickel and cobalt to study the reactivity of reform with chemical recycling process. The catalysts were prepared by three different methods: combustion assisted by microwave, wet impregnation and co-precipitation. All catalysts synthesized have the same amount by weight of the active phases (60% w / w). The other 40 % m/m consists in La2O3 (8% w / w), Al2O3 (30% w / w) and MgO (2%). Oxygen carriers have been named as follows: N or C, nickel or cobalt, followed by the number 3 or 6, meaning 30 to 60% of active phase in the oxide form and C, CI or CP, which means self-combustion assisted by microwave, self-combustion assisted by microwave followed by wet impregnation and co-precipitation. The oxygen carriers were then characterized by the techniques of X-ray diffraction (XRD), surface area (BET), temperature programmed reduction (TPR) and scanning electron microscopy (SEM). The characterization results showed that the different synthesis methods have led to obtaining different morphologies and structures. Redox tests using CH4 as reducing agent and sintetic air as oxidant agent was done with N6C and C6C, N6CI and C6CI and N6CP and C6CP oxygen carriers. The tests revealed different behaviors, depending on active phase and on synthesis procedure. N6C oxygen carrier produced high levels of H2. The C6CI oxygen carrier produced CO2 and H2O without carbon deposits.

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The formulation of public policies, particularly those relating to social housing – SH -, follow a dialectical process of construction, which are involved in the figures of the State and tha Market.The combination of the State and Market remains in constant tension and struggle for power, which provides beyond products (policies, programs and projects), periods of crises and disruptions that can give rise to new institutional arrangements. It is possible to verify a change in the relationship between the State and the Market in the formulation of public policies of SH financing, justified by the context of the Brazilian economy growth, especially after 2003, year that began the first Lula Federal Government , and through the international financial crisis (in 2008). Thus, the State and the Real Estate Market has been undergoing a process of redefinition of their interrelations, articulating new arrangements, new scales of action and new logics of financial valorization of urban space. This peculiarity demanded the rapid thinning of speech and the proposals in the reformulation of housing policies, with the primary result within the pre-existing Growth Acceleration Program – PAC -, the release of My House , My Life – PMCMV -, established by Law 1.977 of the year 2009. Given the above, this research has as study object the relationship between financing public policies of SH, promoted by the State, and behavior of Formal Housing Market. It is believed that the established roles for each agent in the new housing finance model introduced with the PMCMV, have been adapted according to the needs of each location to make this a workable policy. It remains to identify the nature of these adaptations, in other words, what has changed in the performance of each agent involved in this process. Knowing that private capital remains where there is more chance of profit, we tend to believe that most of the adjustments were made on scale of State action. The recommendation of easing urban legislation taken by PMCMV points to how the State has been making these changes in activity to implement the production of social housing by this program. We conclude that in the change for PMCMV, the direct relationship for construction and housing projects financing began to be made between the Caixa Econômica Federal bank and the builders. The city was liberated from the direct interlocutor role between all actors involved in the production of SH and could concentrate on negotiating with the parties, focused on the effectiveness of SH public policies proposed by PMCMV. This ability and willingness for dialogue and negotiation of municipal government (represented by their managers), undoubtedly, represents a key factor for rapprochement between State and Real Estate Market in the City of Parnamirim.

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The public political investments of urban mobility financed by PAC of Cup 2014 have developed discussions and questions by the civil society in Brazil expecting positive results to the urban infrastructure referring to the possible human rights violation and, specially, rights of habitation related to the removing/expropriation noticed. Natal, capital of Rio Grande do Norte, is into this context, due to the urban mobility project linking North Zone of the city to the Arena das Dunas stadium, financed by the PAC of Cup 2014, named West Structural Corridor, that crosses a field of social interest and proposes almost 400 expropriations. This research analyzes how strategies and mechanisms of integration were presented between the mobility project of West Structural Corridor and the Social Interest Habitation affected by this project. We have as hypothesis those projects financed by PAC of Cup 2014/Urban Mobility to Natal/RN present many problems related to the integration of social interest to the housing project, however the National Politics of Urban Development has planned this integration. As a result we detach 3 strategies in the elaboration process about the integration of those politics: (i) integration between municipal secretaries involved in this project; (ii) urban integration of the city; and (iii) integration of public rules or public politics integrated. For each strategy were presented the main mechanisms used to establish the integration of the project. Those mechanisms, however, in this process of establishment/implementation of the empirical research, presented many contradictions and conflicts that compose problems to the integration between the mobility project and the housing area affected.

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Adsorption is a process that has become indispensable due to pollution caused by industrial activity. More economically viable adsorbents are being tested to replace the high cost of materials used. The clays can be used as adsorbents and are low cost materials, natural properties feasible for the application in the adsorption process, structural modifications are performed with ease promoting selective adsorption in these materials. The objective of this study was to synthesize and characterize adsorbents used in the adsorption of organic compounds. The adsorbents were characterized by the techniques of XRD, SEM, FTIR and TG. The results show that the studied materials have affinity to organic compounds and can be applied as adsorbents. The materials studied are viable and can be applied in the treatment of effluents contaminated in industrial scale.

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Searches using organoclays have been the subject of great interest due to its wide application in industry and removal of environmental pollutants. The organoclays were obtained using bentonite (BEN) and cationic surfactants: hexadecyltrimethyl ammonium bromide (HDTMA-Br) and trimethyloctadecyl ammonium bromide (TMOA-Br) in ratios of 50 and 100 % of its ion exchange capacity. The materials were characterized by the techniques of X-ray diffraction (DRX), infrared spectroscopy (IR), X-ray fluorescence (FRX), thermal analysis (TA) and scanning electron microscopy (SEM). The bentonite and organobentonite were used on the adsorption of dyes, Remazol Blue RR (AZ) and Remazol Red RR (VM) in aqueous solution. The adsorption models of Langmuir and Freundlich were used for mathematical description of sorption equilibrium data and obtain the constants of the isotherms. The Freundlich model fit to the data for adsorption equilibrium of bentonite, on the other hand both the model fit to the Langmuir adsorption test of organoclays. The adsorption processes using adsorbents with both dyes interspersed with HDTMA-Br show endothermic and exothermic nature, respectively.

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In Brazil, the discussion about the urban voids appear related to the capitalist urban expansion process, when the urban growth act the cities were expanding toward the periphery, leaving in the interstices vacant land, kept out of the market waiting for the real estate valuation. In Natal, the formation of voids was triggered by the process of fragmentation of space promoted mainly by the urban sprawl with the emergence of new neighborhoods, lots of openings, housing developments and the emergence of new lines of commercial centrality. In this sense, this study aims to understand the role played by urban voids in the real estate dynamics and the production process of the Natal city space. For this, it was adressed the concept building on the conception of different authors and were characterized four types of gaps that best explained the phenomenon in the context of the work proposal addressed, such as idle, empty expectant, empty-brownfield areas and institutional areas. For each of these events were considered an example in the general context of the city through semi-structured interviews with technicians, managers and public officials in promoting the city and /or related to management of urban voids.

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This research aims to provide a reflection on the preservation practices of Brasilia as Cultural Heritage in four analytical/political dimensions: conceptual, urban, political-institutional and legal. In order to do that, the preparation process for the Plan for the Preservation of Brasilia Urban Set (PPCUB) was taken as research object. This preservation plan is representative of the context which determines the relation between goals and preservation practices in the social production process of urban space. Designed by Lucio Costa in 1957, Brasilia received the Cultural Heritage title 27 years later, in 1987. It was recognized a World Heritage Site by the United Nations Educational, Scientific and Cultural (UNESCO) in the same year as it "represents a unique artistic piece of work, a masterpiece of creative genius"; and "an outstanding example of a type of construction or architectural compound that illustrates a significant stage in history" (SILVA, 2003). Brasilia’s urban conception, also recognised in the district and federal levels, gives prominence to the 'urban scales' – monumental, residential, gregarious and bucolic – as the main aspects to be preserved. Despite being an undoubted representative, Brasilia seemingly displays a contradiction. On the one hand, the essential value of the city’s urban design is acknowledged as cultural heritage at international, national and district levels. On the other hand, numerous ways of urban interventions disregard the principles of that conception. In 2012, the international Monitoring Report raised some issues which highlight the following main needs: primary need for clear definition of the urban scales’ characteristics and boundaries; definition of a legal framework that conciliates national and district laws of occupation and use of land; creation of inter-sectors executive authority with both decision-making and financial autonomy; and promotion of heritage educational programs. This report also proposes "to cancel the current process of approval conducted by PPCUB and establish a formal consultation process through a committee made up by GDF and IPHAN, which will enable the active participation of University of Brasilia, the Architects Association, ICOMOS and local organizations" (SEDHAB, 2010). Already in its drafting process, the international recommendations evidence that preserving Brasilia’s urban design conception is not among the goals to be achieved. Thus, this research highlights that the intentional nature of PPCUB’s plans does little towards realizing the current proposals.

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Pozzolanic materials such as rice husk ash are widely used to substitute part of cement, because they react with calcium hydroxide (CH) producing calcium silicate hydrate (C-S-H), which aggregate better physical, chemical and mechanical properties to the cement slurry. The usage of rice husk biomass ash from agribusiness in addition to or partially replacing cement is a noble purpose and a good way of sustainable development which currently is an obsession around the world. The ashes utilized in this study were characterized by: scanning electron microscopy technique (SEM), Fourier transform infrared spectroscopy (FTIR), Energy-dispersive X-ray spectroscopy (EDX) and BET method. The pozzolanic activity of RHA and WRHA in cement slurries was evaluated by: thermal-gravimetric technique and derivative thermogravimetry (TGA/DTG), X-ray diffraction (XRD) and Compressive Strength. The slurries formulated with additions of 10% and 20% of RHA and WRHA were cured for 28 days at 58 °C. The results of thermal analysis demonstrated that a 20% WRHA addition caused a reduction of approximately 73% of Portlandite (calcium hydroxide – CH) phase related to standard slurry (STD). The XRD scans also demonstrated the reduction of the Portlandite peaks’ intensity for each slurry compared with STD slurry. The RHA and WRHA react chemically with Portlandite producing calcium silicate hydrate (C-S-H), confirming their effect as a pozzolanic agent. The WRHA presented the best results as a pozzolanic material.

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O advento da internet causou uma revolução na forma como a sociedade se relaciona. A consolidação das mídias sociais na ambiência digital acentuou o poder das mudanças e forçou a comunicação a rever paradigmas. O imediatismo e a velocidade com que a informação se propaga num processo simétrico de mão dupla – emissor e receptor – mudou a forma de trabalhar, pensar e planejar. O presente trabalho traz uma pesquisa com profissionais de comunicação e analisa como o fator prazo tem impactado no processo do planejamento de longo prazo – tradicionalmente anual – das ações voltadas para o ambiente digital. A pesquisa baseou-se em amplo referencial teórico das áreas de comunicação, marketing, redes e mídias sociais, tecnologia, administração, além de institutos de pesquisas e empresas. A fim de descrever as experiências vividas pelos profissionais, empreendemos ainda uma pesquisa qualitativa com entrevistas em profundidade, com amostra não probabilística, com foco nas disciplinas de marketing e propaganda e relações públicas. Os resultados apontam para um aprendizado ainda sendo conquistado, dia após dia, a partir de tentativas e erros, onde a preocupação dos profissionais fica dividida entre o prazo de antecedência com que é feito um planejamento e a obrigatoriedade de sua revisão contínua.

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À medida que a sociedade evolui, também as profissões evoluem com ela. Uma profissão que tem crescido de forma notável é a de consultor na área das tecnologias de informação. De facto, há alguns anos atrás, esta profissão não tinha o relevo que tem na actualidade, pois com a evolução das tecnologias da informação, as ferramentas ao dispor das empresas diversificaram-se e como tal, a mão-de-obra vai-se especializando nestas ferramentas. As empresas, na impossibilidade de contratar mão-de-obra para instalar, manter e evoluir todas as suas ferramentas, recorrem cada vez mais à experiência de consultores externos; estes são contratados para realizar tarefas específicas que as empresas não têm capacidade de executar com os próprios recursos e a sua ligação com estas entidades termina após a conclusão destas tarefas. Cada vez mais as empresas procuram tirar o máximo partido das ferramentas informáticas à sua disposição e os sistemas de Enterprise Resource Planning não são excepção. À medida que os utilizadores vão usufruindo dos sistemas, surgem novas necessidades que, depois de colmatadas, permitem a sua optimização. Além disso, com a alteração das leis, é preciso adaptar os sistemas para que estes evoluam e possam reflectir os novos requisitos legais. Com o aumento da regulação bancária, as entidades bancárias são obrigadas a comunicar informação sobre as suas finanças ao Banco de Portugal, de modo a que o banco possa analisar a saúde financeira das entidades e emitir recomendações sobre a sua forma de actuar. Esta nova forma de comunicação será efectuada por meio de relatórios em eXtended Business Reporting Language (XBRL). Pretende-se caracterizar a profissão de consultor e apresentar alguns projectos realizados enquanto consultor numa consultora de grande dimensão.

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The growing interest in quantifying the cultural and creative industries, visualize the economic contribution of activities related to culture demands first of all the construction of internationally comparable analysis frameworks. Currently there are three major bodies which address this issue and whose comparative study is the focus of this article: the UNESCO Framework for Cultural Statistics (FCS-2009), the European Framework for Cultural Statistics (ESSnet-Culture 2012) and the methodological resource of the “Convenio Andrés Bello” group for working with the Satellite Accounts on Culture in Ibero-America (CAB-2015). Cultural sector measurements provide the information necessary for correct planning of cultural policies which in turn leads to sustaining industries and promoting cultural diversity. The text identifies the existing differences in the three models and three levels of analysis, the sectors, the cultural activities and the criteria that each one uses in order to determine the distribution of the activities by sector. The end result leaves the impossibility of comparing cultural statistics of countries that implement different frameworks.