992 resultados para Extractive industry


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Novos processos fermentativos, designados por processos de Fermentação Extractiva, são caracterizados por apresentarem etapas de produção e extracção em simultâneo. A extracção líquido-líquido como técnica de separação é amplamente usado na indústria química pela sua simplicidade, baixo custo e facilidade de extrapolação de escala. No entanto o uso de solventes orgânicos nestes processos potencia os riscos ocupacionais e ambientais. Neste contexto, o uso de sistemas de duas fases aquosas baseados em líquidos iónicos, apresenta-se como uma técnica eficaz para a separação e purificação de produtos biológicos. Este trabalho apresenta um estudo integrado sobre o uso de líquidos iónicos não aromáticos foram determinados. A capacidade para a formação de sistemas de duas fases foi estudada para uma vasta gama de líquidos iónicos hidrofílicos com diferentes aniões, catiões e cadeias alqúilicas. A capacidade de separação e purificação de um largo conjunto de líquidos iónicos foi posteriormente investigada, recorrendo-se ao uso de várias biomoléculas modelo de diferentes graus de complexidade, um amino-acido (L-triptofano) e duas enzimas lipolíticas (enzima produzida pela bactéria Bacillus sp. e Candida antarctica lipase B – CaLB). Esta última foi ainda usada para um estudo de biocompatibilidade, tendo sido determinado o efeito de diferentes LIs hidrofílicos na sua actividade enzimática. Este trabalho mostra um estudo ecotoxicológico duma vasta gama de líquidos iónicos e espécies aquáticas, inseridas em diversos níveis tróficos. A bioacumulação foi investigada através do estudo dos coeficientes de distribuição 1-octanol-água (Dow).

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This article critically examines the nature and quality of governance in community representation and civil society engagement in the context of trans-national large-scale mining, drawing on experiences in the Anosy Region of south-east Madagascar. An exploration of functional relationships between government, mining business and civil society stakeholders reveals an equivocal legitimacy of certain civil society representatives, created by state manipulation, which contributes to community disempowerment. The appointment of local government officials, rather than election, creates a hierarchy of upward dependencies and a culture where the majority of officials express similar views and political alliances. As a consequence, community resistance is suppressed. Voluntary mechanisms such as Corporate Social Responsibility (CSR) and the Extractive Industries Transparency Initiative (EITI) advocate community stakeholder engagement in decision making processes as a measure to achieve public accountability. In many developing countries, where there is a lack of transparency and high levels of corruption, the value of this engagement, however, is debatable. Findings from this study indicate that the power relationships which exist between stakeholders in the highly lucrative mining industry override efforts to achieve "good governance" through voluntary community engagement. The continuing challenge lies in identifying where the responsibility sits in order to address this power struggle to achieve fair representation.

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Nowadays, processing Industry Sector is going through a series of changes, including right management and reduction of environmental affections. Any productive process which looks for sustainable management is incomplete if Cycle of Life of mineral resources sustainability is not taken into account. Raw materials for manufacturing are provided by mineral resources extraction processes, such as copper, aluminum, iron, gold, silver, silicon, titanium? Those elements are necessary for Mankind development and are obtained from the Earth through mineral extractive processes. Mineral extraction processes are operations which must take care about the environmental consequences. Extraction of huge volumes of rock for their transformation into raw materials for industry must be optimized to reduce ecological cost of the final product as l was possible. Reducing the ecological balance on a global scale has no sense to design an efficient manufacturing in secondary industry (transformation), if in first steps of the supply chain (extraction) impact exceeds the savings of resources in successive phases. Mining operations size suggests that it is an environmental aggressive activity, but precisely because of its great impact must be the first element to be considered. That idea implies that a new concept born: Reduce economical and environmental cost This work aims to make a reflection on the parameters that can be modified to reduce the energy cost of the process without an increasing in operational costs and always ensuring the same production capacity. That means minimize economic and environmental cost at same time. An efficient design of mining operation which has taken into account that idea does not implies an increasing of the operating cost. To get this objective is necessary to think in global operation view to make that all departments involved have common guidelines which make you think in the optimization of global energy costs. Sometimes a single operational cost must be increased to reduce global cost. This work makes a review through different design parameters of surface mining setting some key performance indicators (KPIs) which are estimated from an efficient point of view. Those KPIs can be included by HQE Policies as global indicators. The new concept developed is that a new criteria has to be applied in company policies: improve management, improving OPERATIONAL efficiency. That means, that is better to use current resources properly (machinery, equipment,?) than to replace them with new things but not used correctly. As a conclusion, through an efficient management of current technologies in each extractive operation an important reduction of the energy can be achieved looking at downstream in the process. That implies a lower energetic cost in the whole cycle of life in manufactured product.

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This paper traces the evolutions of a new generation of students who are predominantly the ‘online generation’; explores the emerging impact of this generation on industry; identifies the changing role of education from traditional classroom to an online environment; and explores the contribution related to integrated marketing communications (IMC). Educational requirements from a business perspective must incorporate global business demands; virtual learning environments progress the online generation towards a post-modern learning state. The central proposition of this paper is that the emergence of IMC in evolving industry practices is influenced by student generations who are producing a new paradigm of alignment between education and industry. This is purely a conceptual exploration using limited examples to provide some context and illustrate the questions raised for consideration.