472 resultados para autothermal reforming
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Ni catalysts supported on gamma-Al(2)O(3) and Mg(Al)O were prepared with and without Rh as a promoter and tested in the reforming of methane in the presence of excess methane, simulating a model biogas. The effects of adding synthetic air on the methane conversion and the formation of carbon were assessed. The catalysts were characterized by X-ray spectroscopy (EDS), surface area (BET), X-ray diffraction (XRD), Temperature-programmed reduction (TPR), X-ray absorption near-edge structure (XANES) and XPD. The results showed that in catalysts without Rh, the Ni interacts strongly with the supports, showing high reduction temperatures in TPR tests. The addition of Rh increased the amount of reducible Ni and facilitated the reduction of the species interacting strongly with the support. In the catalytic tests, the samples promoted with Rh suffered higher carbon deposition. The in situ XPD suggested that on the support gamma-Al(2)O(3), the presence of Rh probably led to a segregation of Ni species with time on stream, leading to carbon deposition. On the support MgAlO, the presence of Rh improved the dispersion of Ni, by reducing the Ni(0) crystallite size, suggesting that in this case the carbon deposition was due to a favoring of CH(4) decomposition by Rh. (C) 2011 Elsevier B.V. All rights reserved.
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The major objective of this paper is to identify, in the light of economic theory and of recent Brazilian and foreign institutional experiences, the best alternative for the reform of the regulatory framework of the domestic financial system, encompassing capital markets, insurance and private complementary social welfare. This paper is divided into four sections: in the first part, we identify the changes in the international and domestic financial systems, currently in an accelerated process of integration (search for similar rules and standards) and convergence (leveling of operational procedures). Next, we evaluate the potential impact of this new environment upon Brazilian economic development. In the second part, we analyze the concept of financial markets efficiency, where a contractualist view of the relationship involving suppliers and consumers of financial services is exposed. We also identify the major differences of focus among the several trends of regulation of the capital markets, insurance and private complementary social welfare In the third part, we present the concepts and the functions of a typical regulatory agency and alternative models of market regulation. In particular, we explore the differences between a regulatory model in which there are several regulatory agencies, each acting in segmented markets, as opposed to one in which there is single agency that regulates, supervises and oversees ali the indicated markets. In the forth and last part, we analyze the Brazilian case, attempting to identify, in the view of economic theory and recent experiences in other countries of the world, the best alternative for reforming present legislation. The basic recommended conclusion is to undertake studies that lead to the establishment of a single regulatory agency, congregating the functions currently performed by the Brazilian Securities Commission (CVM), the Superintendency of Private Insurance (Susep) and the Secretariai of Complementary Welfare (SPC).
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The present study is focused on the analysis of the three main governmental measures occurred in 2000-2006 in Russian defense industry: the creation of the holding structures, the establishing of the state monopoly in arms export, and creation of the United Aviation Construction Corporation (Ob¿edinennaya Aviastroitel¿naya Corporatziya), which was initiated by the President and Government of Russian Federation in 2006. The last project assumes the consolidation and joining of all producers of civil and military aviation into one united corporation in order to save the technological and productive potential of the sector after serious crisis in 1990-s. On the other hand, this project can be considered as one of the measures to establish state control and hierarchy in the defense industry. The current project tries to analyze the necessity and the possible impacts of restructuring processes. In order to perform such analysis, I need to observe the evolution of the sector, which involves the description of the restructuring and reforming of the industry since the disintegration of the Soviet Union. The current situation in aviation sector was shaped by number of reforms performed by Government of Russian Federation, which I describe in phases: conversion, privatization, decentralization, followed by evident desire of the state to establish control over some companies. Later on, I am trying to understand the reasons lying behind all reforms of 2000-2006 and the integration of the industry. I also try to predict which impacts on the companies it will have. The last part presents the main conclusions of the paper.
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A dissertação que ora é apresentada procura identificar se há a adoção dos princípios norteadores da nova gestão pública na gestão dos recursos financeiros que são transferidos para as escolas públicas. Para o desenvolvimento da pesquisa foi feito um levantamento teórico-conceitual sobre o processo de reforma do estado e consultados os dados oficiais sobre administração financeira pública e proficiência dos alunos da rede estadual de Pernambuco. O estudo não identificou relação significativa entre o valor repassado para as escolas e a variação da proficiência dos alunos das escolas estudadas. O resultado do trabalho indica que ainda é muito incipiente a introdução das práticas do modelo gerencial na área de gestão dos recursos públicos para a educação, o que gera atrasos na transferência dos recursos financeiros que as escolas fazem jus. Para reverter esse quadro é necessário romper com os modelos tradicionais de administrar os recursos públicos e a introdução de uma nova cultura de gestão, que permita a atuação de forma ágil e eficiente dos diversos atores envolvidos nessa atividade. A introdução de práticas gerenciais extraídas da gestão privada, como preconiza a nova gestão pública, poderá ser um caminho.
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O objetivo do trabalho é compreender a configuração atual da administração pública brasileira a partir da identificação dos seus atributos caracterizadores, tomando como ponto de partida a rejeição da ideia de modelos rígidos e de ruptura entre esses modelos. Os caminhos teóricos percorridos, e que culminaram com a construção de um quadro teórico preliminar, contemplaram inicialmente: a análise histórico-conceitual das relações entre sociedade, Estado e administração pública; a análise da formação do Estado brasileiro desde o período colonial até os dias atuais; a apresentação das configurações da administração pública brasileira, consagradas pela literatura e seus respectivos atributos. Em seguida, foram resgatadas as bases teóricas da administração pública patrimonial, desde a ideia weberiana de dominação patrimonial até as contribuições de alguns interpretes do pensamento social brasileiro à luz da experiência nacional. Foram apresentadas as bases teóricas da administração pública burocrática, desde o tipo ideal weberiano de dominação racional-legal até a releitura do seu processo de implementação e desenvolvimento no Brasil. Também foram expostas as bases teóricas da administração pública gerencial, desde sua origem a nível mundial até os efeitos de seu marco inaugural no Brasil, o Plano Diretor da Reforma do Aparelho do Estado. A pesquisa, predominantemente qualitativa, assumiu três tipologias: bibliográfica, documental e de campo, permitindo o emprego da triangulação. A pesquisa de campo processou-se por meio de nove entrevistas, com roteiro semi-estruturado, com experts em administração pública brasileira. Para a pesquisa documental, foram selecionadas, primordialmente fontes primárias, com ênfase em documentos oficiais, mas também matérias e reportagens em sites, jornais e revistas. Após a análise do conteúdo das entrevistas e dos documentos, chegou-se a quatro eixos temáticos, cada qual com suas respectivas unidades de significado, que permitiram identificar os atributos presentes na administração pública brasileira e definir sua configuração, são eles: a) heranças patrimonialistas, sendo elas o mandonismo (a personalização do poder), o clientelismo, o favoritismo e a cultura da corrupção; b) (dis)funções burocráticas, sendo elas o formalismo, a hierarquia de cargos e funções, a profissionalização do quadro administrativo e a (im)pessoalidade); c) práticas gerenciais, sendo elas a busca da efetividade, as técnicas do management, a governança e a gestão transparente e participativa; e d) novos arranjos do Estado em rede, sendo elas o Estado Global, a cultura da virtualidade, a lógica das redes e o governo eletrônico. Esses eixos permitiram a construção de um quadro final de interpretações que demonstra a presença de atributos patrimonialistas, burocráticos e gerenciais na administração pública brasileira, e também atributos do que se chama de administração pública em rede, principal achado da pesquisa, o que explica a sua configuração múltipla.
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This paper argues the euro zone requires a government banker that manages the bond market and helps finance country budget deficits. The euro solved Europe’s problem of exchange rate speculation by creating a unified currency managed by a single central bank, but in doing so it replaced the exchange rate speculation problem with bond market speculation. Remedying this requires a central bank that acts as government banker and maintains bond interest rates at sustainable levels. Because the euro is a monetary union, this must be done in a way that both avoids favoring individual countries and avoids creating incentives for irresponsible country fiscal policy that leads to “bail-outs”. The paper argues this can be accomplished via a European Public Finance Authority (EPFA) that issues public debt which the European Central Bank (ECB) is allowed to trade. The debate over the euro’s financial architecture has significant political implications. The current neoliberal inspired architecture, which imposes a complete separation between the central bank and public finances, puts governments under continuous financial pressures. That will make it difficult to maintain the European social democratic welfare state. This gives a political reason for reforming the euro and creating an EPFA that supplements the economic case for reform.
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In this work, ceramic powders belonging to the system Nd2-xSrxNiO4 (x = 0, 0.4, 0.8, 1.2 and 1.6) were synthesized for their use as catalysts to syngas production partial. It was used a synthesis route, relatively new, which makes use of gelatin as organic precursor. The powders were analyzed at several temperatures in order to obtain the perovskite phase and characterized by several techniques such as thermal analysis, X-rays diffraction, Rietveld refinement method, specific surface area, scanning electron microscopy, energy dispersive spectroscopy of X-rays and temperature programmed reduction. The results obtained using these techniques confirmed the feasibility of the synthesis method employed to obtain nanosized particles. The powders were tested in differential catalytic conditions for dry reforming of methane (DRM) and partial oxidation of methane (POM), then, some systems were chosen for catalytic integrals test for (POM) indicating that the system Nd2-xSrxNiO4 for x = 0, 0.4 and 1.2 calcined at 900 °C exhibit catalytic activity on the investigated experimental conditions in this work without showing signs of deactivation
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Ionic oxides with ABO3 structure, where A represents a rare earth element or an alkaline metal and B is a transition metal from group VIII of the periodic table are potential catalysts for oxidation and good candidates for steam reforming reaction. Different methods have been considered for the synthesis of the oxide materials with perovskite structure to produce a high homogeneous material with low amount of impurities and low calcination temperatures. In the current work, oxides with the LaNiO3 formula had been synthesized using the method of the polymeric precursors. The thermal treatment of the materials took place at 300 ºC for 2h. The material supported in alumina and/or zirconia was calcined at 800 ºC temperature for 4h. The samples had been characterized by the following techniques: thermogravimetry; infrared spectroscopy; X-ray diffraction; specific surface area; distribution of particle size; scanning electron microscopy and thermo-programmed reduction. The steam reforming reaction was carried out in a pilot plant using reducing atmosphere in the reactor with a mixture of 10% H2-Argon, a mass about 5g of catalyst, flowing at 50 mL.min-1. The temperature range used was 50 - 1000 oC with a heating rate of 10 oC.min-1. A thermal conductivity detector was used to analyze the gas after the water trapping, in order to permit to quantify the consumption of hydrogen for the lanthanum nickelates (LaNiO3). The results showed that lanthanum nickelate were more efficient when supported in alumina than when supported in zirconia. It was observed that the methane conversion was approximately 100% and the selectivity to hydrogen was about 70%. In all cases were verified low selectivity to CO and CO2
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The production of synthesis gas has received renewed attention due to demand for renewable energies to reduce the emissions of gases responsible for enhanced greenhouse effect. This work was carried out in order to synthesize, characterize and evaluate the implementation of nickel catalysts on MCM-41 in dry reforming reactions of methane. The mesoporous molecular sieves were synthesized using as silica sources the tetraethyl orthosilicate (TEOS) and residual glass powder (PV). The sieves were impregnated with 10% nickel to obtain the metallic catalysts (Ni/MCM-41). These materials were calcined and characterized by Thermogravimetric Analysis (TG), Infrared spectroscopy (FTIR), X-ray Diffraction (XRD), Temperature-Programmed Reduction (TPR) and N2 Adsorption/Desorption isotherms (BET/BJH). The catalytic properties of the samples were evaluated in methane dry reforming with CO2 in order to produce synthesis gas to be used in the petrochemical industry. The materials characterized showed hexagonal structure characteristic of mesoporous material MCM-41 type, being maintained after impregnation with nickel. The samples presented variations in the specific surface area, average volume and diameter of pores based on the type of interaction between the nickel and the mesoporous support. The result of the the catalytic tests showed conversions about 91% CO2, 86% CH4, yelds about 85% CO and 81% H2 to Ni/MCM-41_TEOS_C, and conversions about 87% CO2, 82% CH4, yelds about 70% CO and 59% H2 to Ni/MCM-41_PV_C. The similar performance confirms that the TEOS can be replaced by a less noble materials
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The nanostructures materials are characterized to have particle size smaller than 100 nm and could reach 1 nm. Due to the extremely reduced dimensions of the grains, the properties of these materials are significantly modified relatively when compared with the conventional materials. In the present work was accomplished a study and characterization of the molybdenum carbide, seeking obtain it with particles size in the nanometers order and evaluate its potential as catalyst in the reaction of partial methane oxidation. The method used for obtaining the molybdenum carbide was starting from the precursor ammonium heptamolybdate of that was developed in split into two oven, in reactor of fixed bed, with at a heating rate of 5ºC/min, in a flow of methane and hydrogen whose flow was of 15L/h with 5% of methane for all of the samples. The studied temperatures were 350, 500, 600, 650, 660, 675 and 700ºC and were conducted for 0, 60, 120 and 180 minutes, and the percent amount and the crystallite size of the intermediate phases were determined by the Rietveld refinement method. The carbide obtained at 660ºC for 3 hours of reaction showed the best results, 24 nm. Certain the best synthesis condition, a passivating study was accomplished, in these conditions, to verify the stability of the carbide when exposed to the air. The molybdenum carbide was characterized by SEM, TEM, elemental analysis, ICP-AES, TG in atmosphere of hydrogen and TPR. Through the elemental analysis and ICP-AES the presence carbon load was verified. TG in atmosphere of hydrogen proved that is necessary the passivating of the molybdenum carbide, because occur oxidation in room temperature. The catalytic test was accomplished in the plant of Fischer-Tropsch of CTGAS, that is composed of a reactor of fixed bed. Already the catalytic test showed that the carbide presents activity for partial oxidation, but the operational conditions should be adjusted to improve the conversion
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Various reports concerning catalytic reaction of glycerol for hydrogen production is available. However, economic analyses of this activity are not found yet. The objective of this work is to evaluate the process of hydrogen production via steam reforming of glycerol obtained through transesterification process of bio-oils. The thermochemical process of steam reforming process was determined due to high efficiency, feasibility and lower cost of design, development, operation and maintenance. These bio-oils come from feedstocks largely encountered in Brazil such as soybean, palm, castor bean, peanut and cotton seed as also come from residues such as defective coffee, tallow beef, wastewater (scum) and others. Various findings were obtained such as potential of production of glycerol utilizing residues (considering available amounts in the Brazilian states) and some vegetable feedstocks (considering production of harvested feedstock per hectare). Subsequently, production of hydrogen via steam reforming of generated glycerol, and foreseen electricity production via fuel cells were also determined. An additional estimation was paid for production of H-BIO, an innovative fuel developed by PETROBRAS (Petroleo Brasileiro S.A.), where hydrogen and bio-fuel are utilized and generates propane as co-product. About this work, it was concluded that high amounts of hydrogen and electricity could be produced considering an enormous potential from each cited feedstock being an attractive alternative as distributed electricity source and as an additional source for some activities, inclusively those that produce their own feedstocks such as abattoirs (beef tallow), and wastewater treatment plants. (C) 2010 Elsevier Ltd. All rights reserved.
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The purpose of this paper is to describe the benefits of sugar cane ethanol in Brazil, appointing the productivity of this type of fuel based on hectares of plantation, its carbon dioxide cycle and the contribution to reduce the greenhouse effect. In the following step the uses of ethanol for hydrogen production by steam reforming is analyzed and some comparison with natural gas steam reforming is performed. The sugar cane industry in Brazil, in a near future, in the hydrogen era, could be modified according to our purpose, since besides the production of sugar, and ethylic and anhydric alcohol, Brazilian sugar cane industry will also be able to produce biohydrogen.Fuel cells appear like a promising technology for energy generation. Among several technologies in the present, the PEMFC (proton exchange membrane fuel cell) is the most appropriate for vehicles application, because it combines durability, high power density, high efficiency, good response and it works at relatively low temperatures. Besides that it is easy to turn it on and off and it is able to support present vibration in vehicles. A PEMFC's problem is the need of noble catalysts like platinum. Another problem is that CO needs to be in low concentration, requiring a more clean hydrogen to avoid fuel cell deterioration.One part of this paper was developed in Stockholm, where there are some buses within the CUTE (clean urban transport for Europe) project that has been in operation with FC since January 2004. Another part was developed in Guaratingueta, Brazil. Brazil intends to start up a program of FC buses. As conclusion, this paper shows the economical analysis comparing buses moved by fuel cells using hydrogen by different kinds of production. Electrolyze with wind turbine, natural gas steam reforming and ethanol steam reforming. (C) 2009 Elsevier Ltd. All rights reserved.
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Oxygen carriers are metal oxides which have the ability to oxidize and reduce easily by various cycles. Due to this property these materials are widely usedin Chemical-Looping Reforming processes to produce H2 and syngas. In this work supports based on MCM-41 and La-SiO2 were synthesized by hydrothermal method. After the synthesis step they were calcined at 550°C for 2 hours and characterized by TG, XRD, surface area using the BET method and FTIR spectroscopy. The deposition of active phase, in this case Nickel, took place in the proportions of 5, 10 and 20% by weight of metallic nickel, for use as oxygen carriers.The XRD showed that increasing in the content of Ni supported on MCM-41 resulted in a decrease in spatial structure and lattice parameter of the material. The adsorption and desorption curves of the MCM-41 samples exhibited variations with the increase of Ni deposited. Surface area, average pore diameter and wall density of silica showed significant changes , due to the increase of the active phase on the mesoporous material. By other hand, in the samples with La-SiO2 composition was not observed peaks characteristic of hexagonal structure, in the XRD diffractogram. The adsorption/desorption isotherms of nitrogen observed are type IV, characteristic of mesoporous materials. The catalytic test indicates that the supports have no influence in the process, but the nickel concentration is very important, because the results for minor concentration of nickel are not good. The ratio H2/O2 was close to 2, for all 15 cycles involving the test storage capacity of O2, indicating that the materials are effective for oxygen transport
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Topics of research related to energy and environment have significantly grown in recent years, with the need of its own energy as hydrogen. More particularly, numerous researches have been focused on hydrogen as energy vector. The main portion of hydrogen is presently obtained by reforming of methane or light hydrocarbons (steam, oxy, dry or auto reforming). During the methane steam reforming process the formation of CO2 undesirable (the main contributor to the greenhouse effect) is observed. Thus, an oxide material (sorbent) can be used to capture the CO2 generated during the process and simultaneously shifting the equilibrium of water gas shift towards thermodynamically more favorable production of pure hydrogen. The aim of this study is to develop a material with dual function (catalyst/sorbent) in the reaction of steam reforming of methane. CaO is well known as CO2 sorbent due to its high efficiency in reactions of carbonation and easy regeneration through calcination. However the kinetic of carbonation decreases quickly with time and carbonation/calcination cycles. A calcium aluminate (Ca12Al14O33) should be used to avoid sintering and increase the stability of CaO sorbents for several cycles. Nickel, the industrial catalyst choice for steam reforming has been added to the support from different manners. These bi-functional materials (sorbent/catalyst) in different molar ratios CaO.Ca12Al14O33 (48:52, 65:35, 75:25, 90:10) were prepared by different synthesis methodologies, among them, especially the method of microwave assisted self-combustion. Synthesis, structure and catalytic performances of Ni- CaO.Ca12Al14O33 synthesized by the novel method (microwave assisted selfcombustion) proposed in this work has not being reported yet in literature. The results indicate that CO2 capture time depends both on the CaO excess and on operating conditions (eg., temperature and H2O/CH4 ratio). To be efficient for CO2 sorption, temperature of steam reforming needs to be lower than 700 °C. An optimized percentage corresponding to 75% of CaO and a ratio H2O/CH4 = 1 provides the most promising results since a smaller amount of water avoids competition between water and CO2 to form carbonate and hydroxide. If this competition is most effective (H2O/CH4 = 3) and would have a smaller amount of CaO available for absorption possibly due to the formation of Ca(OH)2. Therefore, the capture time was higher (16h) for the ratio H2O/CH4 = 1 than H2O/CH4 = 3 (7h) using as catalyst one prepared by impregnating the support obtained by microwave assisted self-combustion. Therefore, it was demonstrated that, with these catalysts, the CO2 sorption on CaO modifies the balance of the water gas-shift reaction. Consequently, steam reforming of CH4 is optimized, producing pure H2, complete conversion of methane and negligible concentration of CO2 and CO during the time of capture even at low temperature (650 °C). This validates the concept of the sorption of CO2 together with methane steam reforming
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Health policies in Brazil, the decentralization of SUS management responsibilities for the three spheres of government has driven the creation and regulation of the audits of health services in the National Audit Office, this is a trend of neoliberal policies imposed by international bodies like the World Bank and IMF to peripheral countries characterized by productive restructuring and reforming the state focuses on the presence of two competing projects in the area of health: Health Sector Reform Project which is based on the democratic rule of law with the assumption of health as social right and duty of the State in defending the extension of the conquest of rights and democratization of access to health care guaranteed through the public financing strategies and the effective decentralization of decisions pervaded by social control and privatized Health Project which is based on the state minimum, with a reduction in social spending or in partnerships and privatization, stronger nonprofit sector, subject to capitalist interests, is made effective through strategies targeting health policy and refilantropização actions. In this context, the present study is an analysis on the work of social audits of public health in infants from a qualitative and quantitative approach, embodied by the critical method of dialectical Marxist social theory that enabled us to unveil the characterization, the demands, challenges and outline the profile of Social Work in teams inserted audits of SUS in RN, but also provided evidence to demonstrate the prospects and possibilities of this area of activity of social workers. It was also found that through the audit work that the state fulfill its role as bureaucratic and regulator of health services with efficiency, effectiveness and economy. Yet, paradoxically, the audits of SUS may provide a vehicle for enforcing rights and ensuring the fundamental principles contained in the project of health reform, because it can be configured in a space of political struggle as representing a new field of knowledge production that needs to be appropriate for a theoretical critic able to redirect the social interests in favor of the user. From this perspective, it is concluded that the work of social audits of public health in infants despite the social relevance that prints, as they constitute an activity study of reality and its transformation proposition requires a transformative political action guided the discussion Marxist theory holds that the ethical project professional politician of Social Work