888 resultados para polymers in dispersed form
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The processes involved in the Se electrodeposition, mainly the one related to the formation of H2Se species on Au electrode in perchloric acid solutions, have been investigated through cyclic voltammetry, electrochemical quartz crystal microbalance (EQCM), rotating ring-disc electrode (RRDE), and atomic force microscopy (AFM) techniques. In the experiments performed with the EQCM, with the potential sweep in the negative direction, the responses for the mass variation were divided in three well-defined potential regions: A (from 1.55 to 0.35 V), B (from 0.35 to -0.37 V), and C (from -0.37 to -0.49 V). It was verified that the following processes can occur, respectively: the species (AuO)(2)H2SeO3 was desorbed during the AuO reduction, the reduction of Se(IV) to Se(0), and the formation of H2Se. When the potential was swept in the positive direction, the responses for the mass variation were divided in four well-defined potential regions: D (from -0.49 to 0.66 V), E (from 0.66 to 0.99 V), F (from 0.99 to 1.26 V), and G (from 1.26 to 1.55 V), and the described processes in these regions were, respectively: the Se deposition and adsorption of water molecules and/or perchlorate ions, the Se dissolution, the Se incorporating mass in the form of HO-Se, and the Au oxidation (all potentials are referred to the Ag/AgCl electrode). Making use of the RRDE, using the collection technique, the formation of H2Se species during the Se electrodeposition was investigated. Therefore, it was confirmed that this species is formed on the disc electrode between -0.3 and -0.55 V vs the Ag/AgCl potential range (collecting the oxidized compound onto the ring electrode). AFM images also indicated that the surface topography of the Se-massive deposit on Au is different from the images registered after the formation of H2Se species, confirming the cathodic stripping of Se.
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This paper aims to show how letters, as a genre of literacy, are used in Karagwe in Tanzania, in relation to authority and secrecy. It is shown that literacy, in the form of letters, plays an important role in the negotiation of authority. Authorities as well as ordinary people use letters according to official norms to claim or manifest authority, while grassroots forms of literacy, dominated forms, are used to resist authorities. Through secret messages and letters people find opportunities to resist that are less dangerous than open rebellion, although the effects may be limited because of the secrecy. It is also shown how children are socialized into this pattern of secrecies through literacy as they are used as messengers. When delivering secret letters and messages, they may be said to exercise a passive voice through literacy.
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In this article, we discuss strategies for interaction in spoken discourse, focusing on ellipsis phenomena in English. The data comes from the VOICE corpus of English as a Lingua Franca, and we analyse education data in the form of seminar and workshop discussions, working group meetings, interviews and conversations. The functions ellipsis carries in the data are Intersubjectivity, where participants develop and maintain an understanding in discourse; Continuers, which are examples of back channel support; Correction, both self- and other-initiated; Repetition; and Comments, which are similar to Continuers but do not have a back channel support function. We see that the first of these, Intersubjectivity, is by far the most popular, followed by Repetitions and Comments. These results are explained as consequences of the nature of the texts themselves, as some are discussions of presentations and so can be expected to contain many Repetitions, for example. The speech event is also an important factor, as events with asymmetrical power relations like interviews do not contain so many Continuers. Our clear conclusion is that the use of ellipsis is a strong marker of interaction in spoken discourse.
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In order to explicate Murakami's version of the official culture, I have analyzed the novel with the works of several different theorists. Primarily, I drew my own understanding of the official culture from Raymond Williams's examination of culture in Marxism and Literature. His terminology became helpful in writing about the operation of the System and the Town, though it did not define that operation precisely. Williams's work also introduced me to the theory behind the official culture's manipulation and exclusion of historical aspects in order to create their "official" version of history, from which the official culture draws its identity. For further analysis of the treatment of history, I turned to Friedrich Nietzsche's On the Advantage and Disadvantage of History for Life. Though it examines the official culture's manipulation of history in a much more in-depth manner, it seems to have influenced Murakami's treatment of individual memories and cultural histories. For instance, the herd ofunicoms in the End of the World resembles Nietzsche's description of the ''unhistorical herd," or has the potential to resemble it. With these theories I was able to access the mechanisms of cultural control that Murakami depicts in the form of the System and the Town, and from there I was able to develop a model for how the narrator struggles to subvert that control. Both sides of that struggle are depicted and re-imagined many times throughout Hard-Boiled Wonderland and the End of the World.
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We report results on the optimal \choice of technique" in a model originally formulated by Robinson, Solow and Srinivasan (henceforth, the RSS model) and further discussed by Okishio and Stiglitz. By viewing this vintage-capital model without discounting as a speci c instance of the general theory of intertemporal resource allocation associated with Brock, Gale and McKenzie, we resolve longstanding conjectures in the form of theorems on the existence and price support of optimal paths, and of conditions suÆcient for the optimality of a policy rst identi ed by Stiglitz. We dispose of the necessity of these conditions in surprisingly simple examples of economies in which (i) an optimal path is periodic, (ii) a path following Stiglitz' policy is bad, and (iii) there is optimal investment in di erent vintages at di erent times. (129 words)
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This article investigates the existence of contagion between countries on the basis of an analysis of returns for stock indices over the period 1994-2003. The economic methodology used is that of multivariate GARCH family volatility models, particularly the DCC models in the form proposed by Engle and Sheppard (2001). The returns were duly corrected for a series of country-specific fundamentals. The relevance of this procedure is highlighted in the literature by the work of Pesaran and Pick (2003). The results obtained in this paper provide evidence favourable to the hypothesis of regional contagion in both Latin America and Asia. As a rule, contagion spread from the Asian crisis to Latin America but not in the opposite direction
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Romantic English literature – written at a time when prose fiction was predominantly a medium for sheer entertainment – is rooted in poetry. One or two novelists may exceptionally be granted the adjective “Romantic”, but Mary Shelley is not ranked among them. For centuries, her work has been restricted to that section in handbooks reserved for exotic Gothic literature. This thesis argues that literary criticism has failed to recognize Frankenstein’s obvious relation with the movement. The argument will be fostered by a brief look at such handbooks, and developed through the analysis of the imagery of the novel, so as to trace the Romantic elements there contained. The analysis relies mainly on the frame developed by Northrop Frye concerning the nature and function of imagery in literature. The concept of intertextuality will also be useful as a tool to account for the insertion of images in the novel, and for the novel’s insertion within the Romantic context. The work is divided into three parts. The first contextualizes the main issues set forth by Frankenstein, establishing connections with the life of the author and with the Romantic movement. The second exposes the theoretical basis on which the thesis is grounded. The last presents my reading of the novel’s web of images. In the end, I hope to validate the thesis proposed, that Frankenstein embodies the aesthetic and philosophical assessments of the English Romantic agenda, and therefore deserves to be situated in its due place in the English Literary canon as the legitimate representative of Romanticism in prose form.
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A presente pesquisa foi conduzida na forma de um estudo de caso de duas instituições culturais no contexto francês e brasileiro. O Centro Pompidou é um projeto presidencial de museu financiado pelo Estado, com a missão de tornar a arte moderna em todas as suas expressões acessíveis ao público em geral. O Sesc Pompeia é um centro multidisciplinar de cultura e esporte - financiado pelo dinheiro dos impostos e administrado pela Federação do Comércio . O Sesc Pompéia é dedicado à oferta de educação informal através do cultivo da mente e do corpo. O estudo examina se as teorias de dependência de recursos e de poder podem ser utilizadas para conceituar a relação que o Centro Pompidou e do Sesc Pompéia tem com seus stakeholders financeiros. Mais especificamente, será discutido em que medida o grau de dependência influencia a estratégia de gestão das instituições. O objetivo é de responder a pergunta seguinte: quais são as estratégias que as instituições adotam para reduzir sua dependência com relação a seus principais stakeholders financeiros? Finalmente algumas implicações práticas de gestão serão elaboradas a partir do paralelo entre as estratégias das duas instituições.
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Esta tese é composta por três ensaios sobre o mercado de crédito e as instituições que regem bancarrota corporativa. No capítulo um, trazemos evidências que questionam a ideia de que maiores níveis de proteção ao credor sempre promovem desenvolvimento do mercado de crédito. Desde a publicação dos artigos seminais de La Porta et al (1997,1998), a métrica de proteção ao credor que os autores propuseram -- o índice de proteção ao credor -- tem sido amplamente utilizada na literatura de Law and Finance como variável explicativa em modelos de regressão linear em forma reduzida para determinar a correlação entre proteção ao credor e desenvolvimento do mercado de crédito. Neste artigo, exploramos alguns problemas com essa abordagem. Do ponto de vista teórico, essa abordagem geralmente supõe uma relação monotônica entre proteção ao credor e expansão do crédito. Nós apresentamos um modelo teórico para um mercado de crédito com seleção adversa em que um nível intermediário de proteção ao credor é capaz de implementar equilíbrios first best. Este resultado está de acordo com diversos outros artigos teóricos, tanto em equilíbrio geral quanto em equilíbrio parcial. Do ponto de vista empírico, tiramos proveito das reformas realizadas por alguns países durante as décadas de 1990 e 2000 para implementar uma estratégia inspirada na literatura de treatment effects e estimar o efeito sobre o valor de mercado e sobre a dívida de: i) permitir automatic stay a firmas em recuperação; e ii) conceder aos credores o direito de afastar os administradores. Os resultados que obtivemos apontam para um impacto positivo de automatic stay sobre todas as variáveis que dependem do valor de mercado da firma. Não encontramos efeito sobre dívida, e não encontramos efeitos significativos do direito de afastar administradores sobre valor de mercado ou dívida. O capítulo dois avalia as consequências empíricas de uma reforma na lei de falências sobre um mercado de crédito pouco desenvolvido. No início de 2005, o Congresso Nacional brasileiro aprovou uma nova lei de falências, a lei 11.101/05. Usando dados de firmas brasileiras e não-brasileiras, nós estimamos, usando dois modelos diferentes, o efeito da reforma falimentar sobre variáveis contratuais e não-contratuais de dívida. Ambos os modelos produzem resultados similares. Encontramos um aumento no volume total de dívida e na dívida de longo prazo, e uma redução no custo de dívida. Não encontramos efeitos significativos sobre a estrutura de propriedade da dívida. No capítulo três, desenvolvemos um modelo estimável de equilíbrio em search direcionado aplicado ao mercado de crédito, modelo este que pode ser usado para realizar avaliações ex ante de mudanças institucionais que afetem o crédito (como reformas em leis de falência). A literatura em economia há muito reconhece uma relação causal entre instituições (como leis e regulações) e desenvolvimento dos mercados financeiros. Essa conclusão qualitativa é amplamente reconhecida, mas há pouca evidência de sua importância quantitativa. Com o nosso modelo, é possível estimar como contratos de dívida mudam em resposta a mudanças nos parâmetros que descrevem as instituições da economia. Também é possível estimar o impacto sobre investimentos realizados pelas firmas, bem como caracterizar a distribuição do tamanho, idade e produtividade das firmas antes e depois da mudança institucional. Como ilustração, realizamos um exercício empírico em que usamos dados de firmas brasileiras para simular o impacto de variações na taxa de recuperação de créditos sobre os valores médios e totais de dívida e capital das firmas. Encontramos dívida crescente e capital quase sempre também crescente na taxa de recuperação.
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O Brasil sempre foi um lugar conveniente para se visitar em termos de cultura, diversão e entretenimento. No entanto, este estudo visa o lado educacional do país, particularmente, os estudantes estrangeiros que escolhem o Brasil para programas de intercâmbio. Fins e razões por trás das escolhas dos estudantes foram identificados através de pesquisas quantitativas e qualitativas, juntamente com a revisão da literatura já existente. A pesquisa primária foi feita por meio de entrevistas com estudantes de intercâmbio já no Brasil. Os dados coletados foram analisados e são apresentados de forma estatística, juntamente com a representação gráfica. O seguinte estudo apontou que os denominados “turistas” e, assim chamados, “money seekers”, serem os principais fatores por trás da escolha de estudantes. A pesquisa também mostra que os alunos mais satisfeitos foram os que escolheram o Brasil por causa da qualidade da universidade sede, assim como para explorar as perspectivas de emprego, juntamente com iniciar uma carreira no Brasil.
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This paper examines the extent of rent-sharing in Brazil, between 1988 and 1995, combining two different data sets: annual industrial surveys (pIA) and annual household surveys (PNADs). The aim is to use the trade liberalization policies that took place in Brazil in the early 1990s as a "natural experiment" to examine the impact ofproduct market rents on wages. We first estimate inter-industry wage differentials in Brazil, using the household surveys, afier controlling for various observable workers' characteristics. In a reduced form fixed effects equation, these controlled inter-industry differentials are seen to depend on the industries' rate of effective tariff. We also find that LSDV estimates of the effect of value-added per worker (computed using the industrial surveys) on the wage differentials are positive, but somewhat small. However, we find that instrumenting the valued-added with the effective tariffs more than doubles the estimated rent-sharing coefficient. The paper concludes that rent-sharing is prevalent in the Brazilian manufacturing sector, and this mechanism transferred part of the productivity gains due to trade liberalization to manufacturing workers in the form ofhigher (controlled) wage premium.
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This paper presents a methodology to estimate and identify different kinds of economic interaction, whenever these interactions can be established in the form of spatial dependence. First, we apply the semi-parametric approach of Chen and Conley (2001) to the estimation of reaction functions. Then, the methodology is applied to the analysis financial providers in Thailand. Based on a sample of financial institutions, we provide an economic framework to test if the actual spatial pattern is compatible with strategic competition (local interactions) or social planning (global interactions). Our estimates suggest that the provision of commercial banks and suppliers credit access is determined by spatial competition, while the Thai Bank of Agriculture and Agricultural Cooperatives is distributed as in a social planner problem.
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The Brazilian luxury goods market has been registering substantial growth with many international brands establishing presence in the country. When entering the market, the perfect location seems for most of them to be found in Iguatemi Group’s Shopping Malls. This research focuses the topic of Luxury Market and Retail, in the form of a case study on Iguatemi Group, which tries to understand How is Iguatemi Group creating opportunities for International Luxury Brands in Brazil? To understand the context of the case, the text explores the Brazilian market evolution, its attraction factors and challenges, the location choice methodology used by international luxury brands, and finally, how is the Iguatemi Group creating opportunities for these brands in Brazil. For doing so, a multiple-methods approach was followed so to achieve a non-biased result. In-depth interviews were conducted with Iguatemi’s managers, international luxury brands’ managers and experts in luxury market and retail; non-participant observation was held, and documentation was examined. The research found that the entry of International Luxury Brands in Brazil started about 20 years ago, mainly explained by the positive structural economic reforms Brazil experienced in this period. 60% of the studied brands chose São Paulo’s Iguatemi malls as first location, in particular Iguatemi São Paulo and JK Iguatemi. The preference over these locations relies mainly on the reputation of the Iguatemi brand and on its positioning in the market which seems to be aligned to that of these brands. From its side, Iguatemi has started actively gathering international luxury brands into the market since 15 years ago, and has intensified its action by creating iRetail, an internal company to the group representing some international luxury brands in Brazil, which have, thus, exclusive locations in its malls. The role of Iguatemi, hence, goes beyond that of a real estate company, by approaching the market with a 360° strategy. These findings contribute for academic purposes, in the extent to which they propose a so far rather unexplored topic, and for managerial purposes by describing a best practice in the shopping center sector. However, the study does not mean to be generalized. Consumers’ perspectives on Iguatemi Group were not addressed; rather, the research took a business to business approach.
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Steel is an alloy EUROFER promising for use in nuclear reactors, or in applications where the material is subjected to temperatures up to 550 ° C due to their lower creep resistance under. One way to increase this property, so that the steel work at higher temperatures it is necessary to prevent sliding of its grain boundaries. Factors that influence this slip contours are the morphology of the grains, the angle and speed of the grain boundaries. This speed can be decreased in the presence of a dispersed phase in the material, provided it is fine and homogeneously distributed. In this context, this paper presents the development of a new material metal matrix composite (MMC) which has as starting materials as stainless steel EUROFER 97, and two different kinds of tantalum carbide - TaC, one with average crystallite sizes 13.78 nm synthesized in UFRN and another with 40.66 nm supplied by Aldrich. In order to improve the mechanical properties of metal matrix was added by powder metallurgy, nano-sized particles of the two types of TaC. This paper discusses the effect of dispersion of carbides in the microstructure of sintered parts. Pure steel powders with the addition of 3% TaC UFRN and 3% TaC commercial respectively, were ground in grinding times following: a) 5 hours in the planetary mill for all post b) 8 hours of grinding in the mill Planetary only for steel TaC powders of commercial and c) 24 hours in the conventional ball mill mixing the pure steel milled for 5 hours in the planetary mill with 3% TaC commercial. Each of the resulting particulate samples were cold compacted under a uniaxial pressure of 600MPa, on a cylindrical matrix of 5 mm diameter. Subsequently, the compressed were sintered in a vacuum furnace at temperatures of 1150 to 1250 ° C with an increment of 20 ° C and 10 ° C per minute and maintained at these isotherms for 30, 60 and 120 minutes and cooled to room temperature. The distribution, size and dispersion of steel and composite particles were determined by x-ray diffraction, scanning electron microscopy followed by chemical analysis (EDS). The structures of the sintered bodies were observed by optical microscopy and scanning electron accompanied by EDS beyond the x-ray diffraction. Initial studies sintering the obtained steel EUROFER 97 a positive reply in relation to improvement of the mechanical properties independent of the processing, because it is obtained with sintered microhardness values close to and even greater than 100% of the value obtained for the HV 333.2 pure steel as received in the form of a bar
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)