923 resultados para Ceramic industries
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Advanced ceramic materials constitute a mature technology with a very broad base of current and potential applications and a growing list of material compositions. Within the advanced ceramics category, silicon nitride based ceramics are wear-resistant, corrosion-resistant and lightweight materials, and are superior to many materials with regard to stability in high-temperature environments. Because of this combination the silicon nitride ceramics have an especially high potential to resolve a wide number of machining problems in the industries. Presently the Si3N4 ceramic cutting tool inserts are developed using additives powders that are pressed and sintered in the form of a cutting tool insert at a temperature of 1850 °C using pressureless sintering. The microstructure of the material was observed and analyzed using XRD, SEM, and the mechanical response of this array microstructure was characterized for hardness Vickers and fracture toughness. The results show that Si3N4/20 wt.% (AlN and Y 2O3) gives the best balance between hardness Vickers and fracture toughness. The Si3N4/15 wt.% (AlN and Y 2O3) composition allows the production of a very fine-grained microstructure with low decreasing of the fracture toughness and increased hardness Vickers. These ceramic cutting tools present adequate characteristics for future application on dry machining. © (2010) Trans Tech Publications.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Identifying new uses for residues of industries that process large quantities of biomass, as in bioethanol production, is essential for a sustainable development with reduced impact on the environment, which is the reason why many efforts have been devoted to find noble uses for lignins. in this study, a lignin obtained from sugarcane bagasse in a bioethanol producing plant was carboxymethylated to yield the water-soluble carboxymethyl lignin (CML), which was then used as stabilizing agent in aqueous alumina (Al2O3) suspensions. CML had a degree of substitution 0.46 +/- 0.01, in relation to the C9 unit of lignin, and behaved as a polyelectrolyte in a large pH range owing to the dissociation of carboxylic groups. The action of CML as stabilizing agent of alumina aqueous suspensions was investigated using viscometry, zeta potential, and photon correlation spectroscopy (PCS) measurements, mainly as a function of pH and time. Overall, the results showed that CML had a good performance as a deflocculating agent, because it led to dispersions with low viscosity and small change in particle size as a function of time. The positive effect from the addition of CML was confirmed in the morphological features of the material obtained from the alumina suspensions after elimination of water, as indicated by scanning electron microscopy. The stabilization of alumina suspensions afforded by CML opens the way for similar applications of modified lignins, whose electrical and structural properties may be tuned for specific uses in various industries, including the ceramic industry. (C) 2011 Elsevier B.V. All rights reserved.
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The development of the creative industries “proposition” has caused a great deal of controversy. Even as it has been examined and adopted in several, quite diverse, jurisdictions as a policy language seeking to respond to both creative production and consumption in new economic conditions, it is subject to at times withering critique from within academic media, cultural and communication studies. It is held to promote a simplistic narrative of the merging of culture and economics and represents incoherent policy; the data sources are suspect and underdeveloped; there is a utopianization of “creative” labor; and a benign globalist narrative of the adoption of the idea. This article looks at some of these critiques of creative industries idea and argues against them.
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In studies of media industries, too much attention has been paid to providers and firms, too little to consumers and markets. But with user-created content, the question first posed more than a generation ago by the uses & gratifications method and taken up by semiotics and the active audience tradition (‘what do audiences do with media?’), has resurfaced with renewed force. What’s new is that where this question (of what the media industries and audiences did with each other) used to be individualist and functionalist, now, with the advent of social networks using Web 2.0 affordances, it can be re-posed at the level of systems and populations as well.
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This paper introduces the special issue “China: Internationalizing the Creative Industries”, describing the Australian Research Council funded “MATE” project which provides the conceptual background for the questions the issue explores. The MATE project began with the expectation that as China evolves from its status as a developing country with an emphasis on primary industries and manufacturing, to a mature, market-driven economy benefiting from high levels of international investment, it will become more actively engaged with the global “knowledge economy” and “information society”. In this context, developments in the “creative industries”, which are playing such an important role in developed economies, might reasonably be expected in China. Although China continues to be characterised by strong central-policy settings, as the domestic consumer market matures there is greater scope for consumer-led creative business development. The “MATE” project aimed to capture some of these changes as they began to gain momentum across a range of services: Media, Advertising, Tourism and Education. This special issue continues this theme with papers that explore the theoretical challenges, economic questions and implications, and practical instantiations of creative industries growth in China. All papers contained in this special issue have been peer-reviewed.
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As the 21st century progresses, the most successful economies and societies will be creative ones. Worldwide, governments are producing strategies to encourage the development of creative industries and to strengthen the role of knowledge cities nationally and internationally. There is a significant policy discussion regarding the role of creative clusters in strengthening local economies and significant energy has been expended discussing the many positive outcomes of such developments. This article takes these issues as a starting point and considers the role of creative industries within broader concerns regarding uneven metropolitan development. By developing a typology of jobs across Australia’s metropolitan regions, the article will consider the broad social and economic impacts of uneven development of creative industry jobs between metropolitan regions and also the implications for individual metropolitan regions and policy outcomes.