926 resultados para Recycling textiles


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The primary objective of this investigation has been to develop more efficient and low cost adhesives for bonding various elastomer combinations particularly NR to NR, NR/PB to NR/PB, CR to CR,NR to CR and NR to NBR.A significant achievement of the investigation was the development of solventless and environment friendly solid adhesives for NR to NR and NR/PB to NR/PB particularly for precured retreading. Conventionally used adhesives in this area are mostly NR based adhesive strips in the presence of a dough. The study has shown that an ultra accelerator could be added to the dough just before applying it on the tire which can significantly bring down the retreading time resulting in prolonged tire service and lower energy consumption. Further latex reclaim has been used for the preparation of the solid strip which can reduce the cost considerably.Another significant finding was that by making proper selection of the RF resin, the efficiency and shelflife of the RFL adhesive used for nylon and rayon tire cord dipping can be improved. In the conventionally used RFL adhesive, the resin once prepared has to be added to the latex within 30 minutes and the RFL has to be used after 4 hours maturation time maximum shelf life of the RFL dip solution being 72 hours. In this study a formaldehyde deficient resin was used and hence more flexibility was available for mixing with latex and maturing. It also has a much longer shelf life. In the method suggested in this study, formaldehyde donors were added only in the rubber compound to make up the formaldehyde deficiency in the RFL. The results of this investigation show that the pull through load by employing this method and the conventional method are comparable. This study has also shown that the amount of RF resin with RFL adhesive can be partially replaced by other modifying agents for cost reduction.Cashew nut shell liquid (CNSL) resin can be employed for improving the bonding of dipped nylon and rayon cord with NR.Since CNSL resin cannot be added in the dip solution since it is not soluble in water, it was added in the rubber compound. The amount of wood rosin in the rubber compound can be reduced by using CNSL resin.Another interesting result of the investigation was the use of CR based adhesive modified with chlorinated natural rubber for CR to CR bonding. Addition of chlorinated natural rubber was found to improve sea water resistance of CR based adhesive. In the bonding of a polar rubber like nitrile rubber or polychloroprene rubber to a non polar rubber like natural rubber, an adhesive based on polychloroprene rubber was found to be effective.

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Ship recycling has been considered as the best means to dispose off an obsolete ship. The current state of art of technology combined with the demands of sustainable developments from the global maritime industrial sector has modified the status of erstwhile ‘ship breaking’ involving ship scrap business to a modern industry undertaking dismantling of ships and recycling/reusing the dismantled products in a supply chain of pre owned product market by following the principles of recycling. Industries will have to formulate a set of best practices and blend them with the engineering activities for producing better quality products, improving the productivity and for achieving improved performances related to sustainable development. Improved performance by industries in a sustainable development perspective is accomplished only by implementing the 4E principles, ie.,. ecofriendliness, engineering efficiency, energy conservation and ergonomics in their core operations. The present study has done a comprehensive investigation into various ship recycling operations for formulating a set of best practices.Being the ultimate life cycle stage of a ship, ship recycling activities incorporate certain commercial procedures well in advance to facilitate the objectives of dismantling and recycling/reusing of various parts of the vessel. Thorough knowledge regarding these background procedures in ship recycling is essential for examining and understanding the industrial business operations associated with it. As a first step, the practices followed in merchant shipping operations regarding the decision on decommissioning have been and made available in the thesis. Brief description about the positioning methods and important preparations for the most feasible ship recycling method ie.,. beach method have been provided as a part of the outline of the background information. Available sources of guidelines, codes and rules & regulations for ship recycling have been compiled and included in the discussion.Very brief summary of practices in major ship recycling destinations has been prepared and listed for providing an overview of the global ship recycling activities. The present status of ship recycling by treating it as a full fledged engineering industry has been brought out to establish the need for looking into the development of the best practices. Major engineering attributes of ship as a unique engineering product and the significant influencing factors on her life cycle stage operations have been studied and added to the information base on ship recycling. Role of ship recycling industry as an important player in global sustainable development efforts has been reviewed by analysing the benefits of ship recycling. A brief synopsis on the state of art of ship recycling in major international ship recycling centres has also been incorporated in the backdrop knowledgebase generation on ship recycling processes.Publications available in this field have been reviewed and classified into five subject categories viz., Infrastructure for recycling yards and methods of dismantling, Rules regarding ship recycling activities, Environmental and safety aspects of ship recycling, Role of naval architects and ship classification societies, Application of information technology and Demand forecasting. The inference from the literature survey have been summarised and recorded. Noticeable observations in the inference include need of creation of a comprehensive knowledgebase on ship recycling and its effective implementation in the industry and the insignificant involvement of naval architects and shipbuilding engineers in ship recycling industry. These two important inferences and the message conveyed by them have been addressed with due importance in the subsequent part of the present study.As a part of the study the importance of demand forecasting in ship recycling has been introduced and presented. A sample input for ship recycling data for implementation of computer based methods of demand forecasting has been presented in this section of the thesis.The interdisciplinary nature of engineering processes involved in ship recycling has been identified as one of the important features of this industry. The present study has identified more than a dozen major stake holders in ship recycling having their own interests and roles. It has also been observed that most of the ship recycling activities is carried out in South East Asian countries where the beach based ship recycling is done in yards without proper infrastructure support. A model of beach based ship recycling has been developed and the roles, responsibilities and the mutual interactions of the elements of the system have been documented as a part of the study Subsequently the need of a generation of a wide knowledgebase on ship recycling activities as pointed out by the literature survey has been addressed. The information base and source of expertise required to build a broad knowledgebase on ship recycling operations have been identified and tabulated. Eleven important ship recycling processes have been identified and a brief sketch of steps involved in these processes have been examined and addressed in detail. Based on these findings, a detailed sequential disassembly process plan of ship recycling has been prepared and charted. After having established the need of best practices in ship recycling initially, the present study here identifies development of a user friendly expert system for ship recycling process as one of the constituents of the proposed best practises. A user friendly expert system has been developed for beach based ship recycling processes and is named as Ship Recycling Recommender (SRR). Two important functions of SRR, first one for the ‘Administrators’, the stake holders at the helm of the ship recycling affairs and second one for the ‘Users’, the stake holders who execute the actual dismantling have been presented by highlighting the steps involved in the execution of the software. The important output generated, ie.,. recommended practices for ship dismantling processes and safe handling information on materials present onboard have been presented with the help of ship recycling reports generated by the expert system. A brief account of necessity of having a ship recycling work content estimation as part of the best practices has been presented in the study. This is supported by a detailed work estimation schedule for the same as one of the appendices.As mentioned earlier, a definite lack of involvement of naval architect has been observed in development of methodologies for improving the status of ship recycling industry. Present study has put forward a holistic approach to review the status of ship recycling not simply as end of life activity of all ‘time expired’ vessels, but as a focal point of integrating all life cycle activities. A new engineering design philosophy targeting sustainable development of marine industrial domain, named design for ship recycling has been identified, formulated and presented. A new model of ship life cycle has been proposed by adding few stages to the traditional life cycle after analysing their critical role in accomplishing clean and safe end of life and partial dismantling of ships. Two applications of design for ship recycling viz, recyclability of ships and her products and allotment of Green Safety Index for ships have been presented as a part of implementation of the philosophy in actual practice.

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The paper identifies twelve elements of ship recycling and highlights their respective roles and duties in a proposed ship recycling system. The source and items of knowledgebase for ship recycling have been brought out. A new philosophy focusing clean and safe ship recycling namely design for ship recycling has been introduced based on principles such as ecofriendliness, engineering efficiency, energy conservation and ergonomics. The role of naval architects in ship recycling industry has been described based on the above factors. The paper brings out the role of naval architects in ship recycling the way it has been practiced worldwide and proposed by regulatory bodies. The authors have brought out the new concept of design for ship recycling and various aspects of it. The role of naval architects in the practice of this new design philosophy which is ready to be embraced by the maritime industry has been reiterated.

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During synaptic transmission, NT-filled synaptic vesicles are released by Ca2+-triggered exocytosis at the active zone. Following exocytosis, SV membrane is immediately re-internalized and synaptic vesicles (SVs) are regenerated by a local recycling mechanism within the presynaptic terminal. It is debated whether an endosomal compartment is involved in this recycling process. In contrast, it is well known from cultured mammalian cells, that endocytic vesicles fuse to the early sorting endosome. The early endosome is a major sorting station of the cell where cargo is send into the degradative pathway to late endosome and lysosome or towards recycling. Each trafficking step is mediated by a certain protein of the Rab family. Rab proteins are small GTPases belonging to the Ras superfamily. They accumulate at their target compartments and have thereby been used as markers for the different endocytic organelles in cultured mammalian cells. Rab5 controls trafficking from the PM to the early endosome and has thereby been used as marker for this compartment. A second marker is based on the specific binding of the FYVE zinc finger protein domain to the lipid PI(3)P that is specifically generated at the early endosomal membrane. This study used the Drosophila NMJ as a model system to investigate the SV recycling process. In particular, three questions were addressed: First, is an endosomal compartment present at the synapse? Second, do SVs recycle through an endosome? Third, is Rab5 involved in SV recycling? We used GFP fusions of Rab5 and 2xFYVE to visualize endosomal compartments at the presynaptic terminal of Drosophila third instar larval NMJs. Furthermore, the endosomes are located within the pool of recycling SVs, labeled with the styryl-dye FM5-95. Using the temperature-sensitive mutation in Dynamin, shibirets, we showed that SV recycling involves trafficking through an intermediate endosomal compartment. In cultured mammalian cells, interfering with Rab5 function by expressing the dominant negative version, Rab5SN causes the fragmentation of the endosome and the accumulation of endocytic vesicles. In contrast, when Rab5 is overexpressed enlarged endosomal compartments were observed. In Drosophila, the endosomal compartment was disrupted when loss of function and dominant negative mutants of Rab5 were expressed. In addition, at the ultrastructural we observed an accumulation of endocytic vesicles in Rab5S43N expressing terminals and enlarged endosomes when Rab5 was overexpressed. Furthermore, interfering with Rab5 function using the dominant negative Rab5S43N caused a decrease in the SV recycling kinetics as shown by FM1-43 experiments. In contrast, overexpression of Rab5 or GFP-Rab5 caused an increase in the FM1-43 internalization rate. Finally, standard electrophysiological techniques were used to measure synaptic function. We found that the Rab5-mediated endosomal SV recycling pathway generates vesicles with a higher fusion efficacy during Ca2+-triggered release, compared to SVs recycled when Rab5 function was impaired. We therefore suggest a model in which the endosome serves as organelle to control the SV fusion efficacy and thereby the synaptic strength. Since changes in the synaptic strength are occuring during learning and memory processes, controlling endosomal SV recycling might be a new molecular mechanism involved in learning and memory.

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Urban authorities in Europe are confronted with increasing demands by urban dwellers for allotment gardens, but vacant urban soil tends to be scarce and/or polluted by past industrial activities. A possible solution for local authorities could therefore be to promote rooftop gardening. However little technical information exists on certain forms of rooftop urban agriculture, called Z-Farming. In 2012, a pilot experiment was run in Paris (France). Simple and cheap systems of rooftop gardening were tested on a rooftop using as crop substrates only local urban organic waste so as to contribute to the urban metabolism. Production levels and heavy metal contents in cropping substrates and edible vegetables were measured. Available results show (i) high levels of crop production with limited inputs compared to land professional gardening, (ii) low levels of heavy metal pollutants in the edible parts of the crops, especially for Cd and Pb with respect to EU norms for vegetables and (iii) positive influence on yields on organizing the substrate in layers and enhancing the biological activity through earthworm inoculation. These encouraging results allow us to consider that rooftop gardening is feasible and seem to have a great potential to improve urban resiliency. It will nevertheless be necessary to identify more precisely the types of roof that can be used and to assess more fully the generic result of the low level of pollution, as well as the global sustainability of these cropping systems.

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Training on techniques needed to use the textile screen printing facilities at WSA. Please note that watching these videos does not mean you are authorised to use these machines, this is for reference after a formal in person induction.

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En esta medida, el propósito de la investigación es identificar el impacto de la IED en el desarrollo económico colombiano durante el periodo 1991-2003 en el marco del sector textil-confección, a la vez que intenta explicar las condiciones necesarias y el rol que deben asumir los diferentes actores involucrados para atraer de una manera más efectiva la IED en el sector textiles y confecciones.

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El presente proyecto de grado se inscribe bajo el proyecto de Responsabilidad Social Empresarial de la línea de investigación de Realidad Empresarial de la Facultad de Administración de la Universidad del Rosario. El problema de investigación surge de dos problemas actuales, que convergen en la insostenibilidad a largo y mediano plazo de la manera en que se hacen la mayoría de los negocios hoy en día. El primer problema, es el de suficiencia, se evidencia desde el punto de vista del consumidor, el cual pareciera estar diseñado para comprar y acumular objetos y cosas que luego de un tiempo irán a parar a la basura. El segundo problema es el modelo de negocio que extrae recursos, los transforma, los comercializa de manera repetitiva y obliga al cliente a seguir comprando, olvidando que la mayoría de cosas que produce, terminan en el basurero. La deficiencia actual del consumismo insostenible y del diseño que no piensa en las generaciones futuras son dos caras de la misma moneda. Por eso es que se estudia el problema desde la perspectiva tanto del consumidor, como del productor. Las tendencias internacionales relacionadas con la sostenibilidad están llevando a los negocios por una nueva senda, la cual les dará ventajas competitivas a los adoptadores tempranos. A raíz de los problemas planteados y con el objetivo de encontrar la sostenibilidad empresarial, se estudia una posible solución para cada actor del problema. Por el lado del consumidor, se analiza la teoría que gira alrededor del consumo responsable y de cómo los consumidores tienen el poder de causar un efecto positivo con lo que mejor saben hacer: comprando (y eligiendo que comprar). Por el lado del productor se estudia un nuevo modelo de negocios llamado el sistema producto-servicio, el cual se enfoca a satisfacer necesidades de los clientes por medio de una combinación de prestación de servicios y facilitación de productos, en vez de la comercialización de estos. Es decir que en vez de vender cosas que los consumidores quieran acumular (problema de suficiencia), se les vende soluciones que satisfagan sus necesidades, reteniendo la compañía la propiedad sobre los productos que integran al servicio. Se estudia también de que maneras este modelo particular de sistemas producto-servicio puede ser recibido por los consumidores de hoy en día, tan acostumbrados al modelo actual. Se quiere explorar el sistema de productos y servicio como una alternativa empresarial perdurable que solucione los retos ambientales del siglo XXI. Para poder probar la viabilidad de este hipotético modelo que cambia los patrones de interacción de las empresas con los usuarios, se plantea una idea de negocio que integre productos y servicios para satisfacer las necesidades del cliente. Se escogió un área viii caracterizada por ser de las más consumistas y acumuladoras en cuanto al volumen de compras anual de los clientes: el negocio de la ropa. Y no solo cualquier tipo de ropa, sino el de la moda rápida, un modelo que obliga a los consumidores a comprar ropa con una frecuencia aún mayor. Se hizo esto con el objetivo de probar que el modelo propuesto puede funcionar inclusive bajo los supuestos más “consumistas” que existen hoy en día.

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Ofrece a los estudiantes de nivel elemental los recursos para aprender y practicar el inglés y preparar el certificado Cambridge Key English Test (KET). Abarca cuatro áreas principales: situaciones, para el uso del idioma en la vida cotidiana; vocabulario; gramática; y escritura, que incluye consejos para estudiar, ayuda con la ortografía, corrección de errores y expresiones útiles.

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Ofrece a los estudiantes de nivel intermedio-bajo a intermedio los recursos para mejorar su inglés general y preparar el certificado Cambridge Preliminary Test (PET). Abarca cuatro secciones: gramática; vocabulario; situaciones para el uso del idioma en la vida cotidiana; y escritura, que incluye modelos de escritos, ayuda con la ortografía, consejos sobre técnicas de redacción y expresiones útiles.

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Ofrece a los estudiantes de nivel avanzado los recursos para mejorar su inglés general o preparar el Cambridge Certificate in Advanced English (CAE) o el Cambridge Certificate of Proficiency in English (CPE). Abarca cinco secciones: gramática; frases verbales; vocabulario; estudio de palabras, modismos, frases hechas para profundizar en las áreas lingüísticas que causan dificultades al estudiante avanzado; y escritura, que incluye estilos, frases, ejercicios prácticos y los tipos de composiciones exigidas en el CAE y en el CPE.