972 resultados para advanced process oxidation
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Since molecularly imprinted polymers (MIPs) are designed to have a memory for their molecular templates it is easy to draw parallels with the affinity between biological receptors and their substrates. Could MIPs take the place of natural receptors in the selection of potential drug molecules from synthetic compound libraries? To answer that question this review discusses the results of MIP studies which attempt to emulate natural receptors. In addition the possible use of MIPs to guide a compound library synthesis towards a desired biological activity is highlighted. © 2005 Elsevier B.V. All rights reserved.
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Purpose – Developing countries are heavily dependent on the resources and commitment of foreign providers to ensure successful adoption of advanced manufacturing technology (AMT). The purpose of this paper is to describe the important role of buyer-supplier relationships (BSRs) in the process of technology selection, acquisition and implementation. Design/methodology/approach – A survey of 147 Malaysian manufacturing firms is the main instrument used in the research investigations and data analysis is carried out by the structured equation modelling (SEM) technique. In particular, the authors examine the impact on performance of different patterns of relationship between technology buyers and suppliers. Findings – Although the majority of the firms reported improvements in their performance since the acquisition of AMT, closer investigation reveals that those demonstrating a closer relationship with their suppliers are more likely to achieve higher levels of technology and implementation performance (IP) than those that do not. Research limitations/implications – The paper only assesses the strength of BSR from the buyers' perspective and they may have limited experience of acquisition, whereas suppliers may have more experience of selling AMT. Also, the research is undertaken in Malaysia and the findings may be different in other countries, especially where the technology being acquired is not imported but sourced locally. Practical implications – The findings relating to BSR, technology acquisition and IP have important implications both for customers and supplier firms as well as for industrial policy makers in developing countries. Originality/value – The result of the research provides useful insights that are especially pertinent to an improved understanding of BSRs in the procurement of capital equipment, about which the current research literature is limited.
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As levels of investment in advanced manufacturing systems increase, effective project management becomes ever more critical. This paper demonstrates how the model proposed by Mintzberg, Raisinghani and Theoret in 1976, which structures complicated strategic decision processes, can be applied to the design of new production systems for both descriptive and analytical research purposes. This paper sets a detailed case study concerning the design and development of an advanced manufacturing system within the Mintzberg decision model and so breaks down the decision sequence into constituent parts. It thus shows how a structured model can provide a framework for the researcher who wishes to study decision episodes in the design of manufacturing facilities in greater depth.
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In recent years, technologically advanced methodologies such as Translog have gained a lot of ground in translation process research. However, in this paper it will be argued that quantitative research methods can be supplemented by ethnographic qualitative ones so as to enhance our understanding of what underlies the translation process. Although translation studies scholars have sometimes applied an ethnographic approach to the study of translation, this paper offers a different perspective and considers the potential of ethnographic research methods for tapping cognitive and behavioural aspects of the translation process. A number of ethnographic principles are discussed and it is argued that process researchers aiming to understand translators’ perspectives and intentions, how these shape their behaviours, as well as how translators reflect on the situations they face and how they see themselves, would undoubtedly benefit from adopting an ethnographic framework for their studies on translation processes.
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Wastewater treatment coupled with energy crop cultivation provides an attractive source of cheap feedstock. This study reviews an advanced, closed-loop bioenergy conversion process [biothermal valorisation of biomass (BtVB)], in which pyroformer is coupled to a gasifier. BtVB process was developed at European Bioenergy Research Institute (EBRI), Aston University, UK and demonstrates an improved method for thermal conversion of ash-rich biomass.
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This thesis reports the results of research into the connections between transaction attributes and buyer-supplier relationships (BSR) in advanced manufacturing technology (AMT) acquisitions and implementation. It also examines the impact of the different patterns of BSR on performance. Specifically, it addresses the issues of how the three transaction attributes; namely level of complexity, level of asset specificity, and level of uncertainty, can affect the relationships between the technology buyer and suppler in AMT acquisition and implementation, and then to see the impact of different patterns of BSR on the two aspect of performance; namely technology and implementation performance. In understanding the pohenomena, the study mainly draws on and integrates the literature of transaction cost economics theory,buyer-supplier relationships and advanced manufacturing technology as a basis of theoretical framework and hypotheses development.data were gathered through a questionnaire survey with 147 responses and seven semi-structured interviews of manufacturing firms in Malaysia. Quantitative data were analysed mainly using the AMOS (Analysis of Moment Structure) package for structural equation modeling and SPSS (Statistical Package for Social Science) for analysis of variance (ANOVA). Data from interview sessions were used to develop a case study with the intention of providing a richer and deeper understanding on the subject under investigation and to offer triangulation in the research process. he results of the questionnaire survey indicate that the higher the level of technological specificity and uncertainty, the more firms are likely to engage in a closer relationship with technology suppliers.However, the complexity of the technology being implemented is associated with BSR only because it is associated with the level of uncertainty that has direct impact upon BSR.The analysis also provides strong support for the premise that developing strong BSR could lead to an improved performance. However, with high levels of transaction attribute, implementation performance suffers more when firms have weak relationships with technology suppliers than with moderate and low levels of transaction attributes. The implications of the study are offered for both the academic and practitioner audience. The thesis closes with reports on its limitations and suggestions for further research that would address some of these limitations.
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This thesis is concerned with the management processes concerned with complex strategic decision in organisations. The research has sought to explore these processes by taking as its focus the reconstruction of decision processes a) on the basis of an historical study of an industry and in particular a major company in that industry; and b) the perception and understanding of strategic decision processes and change by managers involved in companies in that industry. The main body of analysis and theoretical contributions arise from the detailed analysis of extended depth interviews with managers carried out in 1980 and 1983 which trace thirteen years of the strategic development of a firm. In so doing, extensive use is made of verbatim accounts by managers of events and their interpretation of events. This is then compared with data gathered from.similar interviews with managers of two other companies and examined in the light of existing research and theory in the field. The thesis both provides a detailed insight into the processes associated with the identification and resolution of complex strategic issues and also generates a body of theory concerning the mechanisms by which strategic decisions and the processes of strategic change are interwoven with the cultural and political fabric of organisations. The thesis is divided into four parts. The first part deals with the background to the research, provid1ng a fuller summary of the purpose, structure and content of the thesis and a discussion of relevant previous research and the methodology employed herein. The second part mainly provides case studies of the industry and the main company studied. The third part is a detailed presentation and analysis of data. The fourth part is a synthesis of the findings and consolidation of the theoretical interpretation advanced in the thesis.
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High velocity oxyfuel (HVOF) thermal spraying is one of the most significant developments in the thermal spray industry since the development of the original plasma spray technique. The first investigation deals with the combustion and discrete particle models within the general purpose commercial CFD code FLUENT to solve the combustion of kerosene and couple the motion of fuel droplets with the gas flow dynamics in a Lagrangian fashion. The effects of liquid fuel droplets on the thermodynamics of the combusting gas flow are examined thoroughly showing that combustion process of kerosene is independent on the initial fuel droplet sizes. The second analysis copes with the full water cooling numerical model, which can assist on thermal performance optimisation or to determine the best method for heat removal without the cost of building physical prototypes. The numerical results indicate that the water flow rate and direction has noticeable influence on the cooling efficiency but no noticeable effect on the gas flow dynamics within the thermal spraying gun. The third investigation deals with the development and implementation of discrete phase particle models. The results indicate that most powder particles are not melted upon hitting the substrate to be coated. The oxidation model confirms that HVOF guns can produce metallic coating with low oxidation within the typical standing-off distance about 30cm. Physical properties such as porosity, microstructure, surface roughness and adhesion strength of coatings produced by droplet deposition in a thermal spray process are determined to a large extent by the dynamics of deformation and solidification of the particles impinging on the substrate. Therefore, is one of the objectives of this study to present a complete numerical model of droplet impact and solidification. The modelling results show that solidification of droplets is significantly affected by the thermal contact resistance/substrate surface roughness.
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The development of an advanced outdoor valve requires coordinated research in the areas of light-triggered self-protecting thyristors, light triggering systems, insulation, cooling and mechanical design aspects. This thesis addresses the first two areas primarily, with a conceptual discussion of the remainder. Using the experience gained from evaluation of a prototype thyristor and computer IKdelling of turn-on behaviour, a light-triggered thyristor with immunity to damage from weak optical triggering and dv/dt triggering was designed, manufactured and evaluated. The optical turn-on process was investigated by measuring currents and voltages in the gate structure during turn-on, and this yielded insights not obtained through conventional measurement techniques. The mechanism by which the thyristor was immune to weak triggering damage is explained, and techniques for optimising the design of the gate structure are proposed. The most significant achievement, however, was the first demonstration of the feasibility of self-protection against forward recovery failure onditions. Furthermore, this was achieved without the need for complex structures or high levels of irradiation. The perfomance of the devices was limited by the inrush capability of the Zones, but it is believed that this can be improved by conventional means. A light triggering system was developed using sem~conductor lasers, and this incorporated several improvements over prior art In terms of optical performance and flexibility.
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The oxidation of lipids has long been a topic of interest in biological and food sciences, and the fundamental principles of non-enzymatic free radical attack on phospholipids are well established, although questions about detail of the mechanisms remain. The number of end products that are formed following the initiation of phospholipid peroxidation is large, and is continually growing as new structures of oxidized phospholipids are elucidated. Common products are phospholipids with esterified isoprostane-like structures and chain-shortened products containing hydroxy, carbonyl or carboxylic acid groups; the carbonyl-containing compounds are reactive and readily form adducts with proteins and other biomolecules. Phospholipids can also be attacked by reactive nitrogen and chlorine species, further expanding the range of products to nitrated and chlorinated phospholipids. Key to understanding the mechanisms of oxidation is the development of advanced and sensitive technologies that enable structural elucidation. Tandem mass spectrometry has proved invaluable in this respect and is generally the method of choice for structural work. A number of studies have investigated whether individual oxidized phospholipid products occur in vivo, and mass spectrometry techniques have been instrumental in detecting a variety of oxidation products in biological samples such as atherosclerotic plaque material, brain tissue, intestinal tissue and plasma, although relatively few have achieved an absolute quantitative analysis. The levels of oxidized phospholipids in vivo is a critical question, as there is now substantial evidence that many of these compounds are bioactive and could contribute to pathology. The challenges for the future will be to adopt lipidomic approaches to map the profile of oxidized phospholipid formation in different biological conditions, and relate this to their effects in vivo. This article is part of a Special Issue entitled: Oxidized phospholipids-their properties and interactions with proteins.
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Purpose - This "research note" sets out to fuel the debate around the practices and technologies within operations that are critical to success with servitization. It presents a study of four companies which are delivering advanced services and reports on the organisation and skill-sets of people within these. Design/methodology/approach - This has been case-based research at four manufacturers leading in their delivery of services. Findings - It describes the desirable behaviour of people in the front-line of service delivery, identifies the supporting skill-sets, how these people are organised, and explains why all these factors are so important. Originality/value - This paper contributes to the understanding of the servitization process and, in particular, the implications to broader operations of the firm. © 2013 Emerald Group Publishing Limited. All rights reserved.
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Purpose: This paper aims to explore practices and technologies successfully servitised manufacturers employ in the delivery of advanced services. Design/methodology/approach: A case study methodology is applied across four manufacturing organisations successful in servitization. Through interviews with personnel across host manufacturers, their partners, and key customers, extensive data are collected about service delivery systems. Analyses identify convergence in their practices and technologies. Findings: Six distinct technologies and practices are revealed: facilities and their location, micro-vertical integration and supplier relationships, information and communication technologies (ICTs), performance measurement and value demonstration, people deployment and their skills, and business processes and customer relationships. These are then combined in an integrative framework that illustrates how operations are configured to successfully deliver advanced services. Research limitations/implications: The analyses are reductive and rationalising. Future studies could identify other technologies and practices. Case study as a method is inherently limited in the extent to which findings can be generalised. Practical implications: Awareness and interest in servitization is growing, yet adoption of a servitization strategy requires particular organisational capabilities on the part of the manufacturer. This study identifies technologies and practices that underpin these capabilities. Originality/value: This paper contributes to the understanding of the servitization process and, in particular, the implications to broader operations of the firm. © Emerald Group Publishing Limited.
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Fischer-Tropsch synthesis (FTS) is a process which converts syn-gas (H2 and CO) to synthetic liquid fuels and valuable chemicals. Thermal gasification of biomass represents a convenient route to produce syn-gas from intractable materials particularly those derived from waste that are not cost effective to process for use in biocatalytic or other milder catalytic processes. The development of novel catalysts with high activity and selectivity is desirable as it leads to improved quality and value of FTS products. This review paper summarises recent developments in FT-catalyst design with regards to optimising catalyst activity and selectivity towards synthetic fuels. © 2014 the Partner Organisations.
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Servitization is the process by which manufacturers add services to their product offerings and even replace products with services. The capabilities necessary to develop and deliver advanced services as part of servitization are often discussed in the literature from the manufacturer’s perspective, e.g., having a service-focused culture or the ability to sell solutions. Recent research has acknowledged the important role of customers and, to a lesser extent, other actors (e.g., intermediaries) in bringing about successful servitization, particularly for use-oriented and results-oriented advanced services. The objective of this study is to identify the capabilities required to successful develop advanced services as part of servitization by considering the perspective of manufacturers, intermediaries and customers. This study involved interviews with 33 managers in 28 large UK-based companies from these three groups, about servitization capabilities. The findings suggest that there are eight broad capabilities that are important for advanced services; 1) personnel with expertise and deep technical product knowledge, 2) methodologies for improving operational processes, helping to manage risk and reduce costs, 3) the evolution from being a product- focused manufacturer to embracing a services culture, 4) developing trusting relationships with other actors in the network to support the delivery of advanced services, 5) new innovation activities focused on financing contracts (e.g., ‘gain share’) and technology implementation (e.g., Web-based applications), 6) customer intimacy through understanding their business challenges in order to develop suitable solutions, 7) extensive infrastructure (e.g., personnel, service centres) to deliver a local service, and 8) the ability to tailor service offerings to each customer’s requirements and deliver these responsively to changing needs. The capabilities required to develop and deliver advanced services align to a need to enhance the operational performance of supplied products throughout their lifecycles and as such require greater investment than the capabilities for base and intermediate services.
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We present recent results on femtosecond microfabrication of key components for integrated optics such as highly curved low-loss waveguides in glasses, depressed cladding waveguides in crystals. Details of microfabrication and characterisation are discussed. © 2009 Optical Society of America.