796 resultados para Green Star,


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Implantable devices must exhibit mechanical properties similar to native tissues to promote appropriate cellular behavior and regeneration. Herein, we report a new membrane manufacture method based on the synthesis of polyelectrolyte complexes (PECs) that exhibit saloplasticity, i.e. variable physical-chemistry using salt as a plasticizer. This is a Green Chemistry approach, as PECs generate structures that are stabilized solely by reversible electrostatic interactions, avoiding the use of harmful crosslinkers completely. Furthermore, natural polyelectrolytes - chitosan and alginate - were used. Upon mixing them, membranes were obtained by drying the PECs at 37ºC, yielding compact PECs without resorting to organicsolvents. The plasticizing effect of salt after synthesis was shown by measuring tensile mechanical properties, which were lower when samples were immersed in high ionic strength solutions.Salt was also used during membrane synthesis in different quan- tities (0 M, 0.15 M and 0.5 M in NaCl) yielding structures with no significant differences in morphology and degradation (around 15% after 3 months in lysozyme). However, swelling was higher (about 10x) when synthesized in the presence of salt. In vitro cell studies using L929 fibroblasts showed that cells adhered and proliferated preferentially in membranes fabricated in the presence of salt (i.e. the membranes with lower tensile strength). Structures with physical-chemical properties controlled with precision open a path to tissue engineering strategies depending on fine tuning mechanical properties and cellular adhesion simply by changing ionic strength during membrane manufacture

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Marine ecosystem can be considered a rather exploited source of natural substances with enormous bioactive potential. In Mexico macro-algae study remain forgotten for research and economic purposes besides the high amount of this resource along the west and east coast. For that reason the Bioferinery Group of the Autonomous University of Coahuila, have been studying the biorefinery concept in order to recover high value byproducts of Mexican brown macro-algae including polysaccharides and enzymes to be applied in food, pharmaceutical and energy industry. Brown macroalgae are an important source of fucoidan, alginate and laminarin which comprise a complex group of macromolecules with a wide range of important biological properties such as anticoagulant, antioxidant, antitumoral and antiviral and also as rich source of fermentable sugars for enzymes production. Additionally, specific enzymes able to degrade algae matrix (fucosidases, sulfatases, aliginases, etc) are important tools to establish structural characteristics and biological functions of these polysaccharides. The aims of the present work were the integral study of bioprocess for macroalgae biomass exploitation by the use of green technologies as hydrothermal extraction and solid state fermentation in order to produce polysaccharides and enzymes (fucoidan and fucoidan hydrolytic enzymes). This work comprises the use of the different bioprocess phases in order to produce high value products with lower time and wastes.

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Graphics based systems of Augmented and Alternative Communication are widely used to promote communication in people with Autism Spectrum Disorders. This study discusses an integration of Augmented Reality in communication interventions, by relating elements of Augmented and Alternative Communication and Applied Behaviour Analysis strategies. An architecture for an Augmented Reality based interactive system to assist interventions is proposed. STAR provides an Augmented Reality tool to assist interventions performed by therapists and support for parents to join in and participate in the child’s intervention. Finally we report on the usage of the Augmented Reality tool in interventions with children with Autism Spectrum Disorders.

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A Zero waste management is believed to be one of methods to gain sustainability in urban areas. Take advantages of resources as enough as the needs and process it until the last part to be wasted is a contribution to take care the environment for the next generation. Reduce, reuse, and recycle are three simplesactivities which are until nowadays consideredas the back bone of zero waste. Jonggolgreen city is a new urban area in Indonesia with a 100 ha of surface area zoned as education tourism area. It is an independent area with pure natural resources of water, air, and land to be managed and protected. It is planned as green city through zero waste management since2013. In this preliminary period, a monitoring tool is being prepared by applying a Life Cycle Analysis (LCA) for urban areas [1]. This paper will present an explanatory assessment ofthe zero waste management for Jonggolgreen city. The existing situation will be examined through LCA and afterwards,the new program and the proposed green design to gain the next level of zero waste will be discussed. The purpose is to track the persistence of the commitment and the perception of the necessary innovationsin order to achieve the ideal behavior level of LCA.

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Stress/strain sensors constitute a class of devices with a global ever-growing market thanks to their use in many fields of modern life. They are typically constituted by thin metal foils deposited on flexible supports. However, the low inherent resistivity and limited flexibility of their constituents make them inadequate for several applications, such as measuring large movements in robotic systems and biological tissues. As an alternative to the traditional compounds, in the present work we will show the advantages to employ a smart material, polyaniline (PANI), prepared by an innovative environmentally friendly route, for force/strain sensor applications wherein simple processing, environmental friendliness and sensitivity are particularly required.

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This paper provides an overview of properties and application of natural fibre composites. Natural fibre market, merits and demerits, surface treatment techniques, properties of some recently developed natural fibre composites and applications have been discussed.

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Multiarm star polymers are attractive materials due to their unusual bulk and solution properties. They are considered analogues of dendrimers with a wide range of applications, such as drug delivery, membranes, coatings and lithography.1 The advent of controlled polymerization made possible the existence of this unique class of organic nanoparticles (ONPs).2 Two major synthetic strategies are usually employed in the preparation of star polymers, the core-first and arm-first approaches. The core-first approach involves a controlled living polymerization using a multiarm initiator core while the arm-first methodology is based in the quenching of living polymers with multifunctional coupling agent or bifunctional vinyl compounds. Herein, we present the synthesis and characterization of a new star polymer, the multiarm star poly(2-hydroxyethyl methacrylate). The tetra-armed star polymer was prepared by reversible addition fragmentation chain-transfer (RAFT) polymerization using the core-first approach. The RAFT chain-transfer agent (RAFT CTA) pentaerythritol tetrakis[2-(dodecylthiocarbonothioylthio)-2-methylpropionate] was used as multiarm initiator core were 2-hydroxyethyl methacrylate (HEMA) was polymerized using AIBN as radical initiator. Structural characterization was performed by 1H NMR and FTIR. The new polymer is able to uptake large quantities of organic solvents, forming gels. The rheological behavior of these gels was also investigated.

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The present paper is devoted to the study of linear maps preserving certain relations, such as the sharp partial order and the star partial order in semisimple Banach algebras and C*-algebras.

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Radical cyclization continues to be a central methodology for the preparation of natural products containing heterocyclic rings. Hence, some electrochemical results obtained by cyclic voltammetry and controlled-potential electrolysis in the study of electroreductive intramolecular cyclization of ethyl (2S, 3R)-2-bromo-3-propargyloxy-3-(2’,3’,4’,6’-tetra-O-acetyl-beta-D-glucopyranosyloxy) propanoate (1a), 2-bromo-3-allyloxy-3-(2’,3’,4’,6’-tetra-O-acetyl-beta-D-glucopyranosyloxy)propanoate (1b), 2-bromo-[1-(prop-2-yn-1-yloxy)propyl]benzene (1c) and [1-bromo-2-methoxy-2-(prop-2’-yn-1-yloxy)ethyl]benzene (1d) promoted by (1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane)nickel(I), [Ni(tmc)]+, electrogenerated at glassy carbon cathodes in ethanol and ethanol:water mixtures containing tetraalkylammonium salts, are presented. During controlled-potential electrolyses of solutions containing [Ni(tmc)]2+ and bromoalkoxylated compounds (1) catalytic reduction of the latter proceeds via one-electron cleavage of the carbon–bromine bond to form a radical intermediate that undergoes cyclization to afford the substituted tetrahydrofurans.

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Let V be an infinite-dimensional vector space and for every infinite cardinal n such that n≤dimV, let AE(V,n) denote the semigroup of all linear transformations of V whose defect is less than n. In 2009, Mendes-Gonçalves and Sullivan studied the ideal structure of AE(V,n). Here, we consider a similarly-defined semigroup AE(X,q) of transformations defined on an infinite set X. Quite surprisingly, the results obtained for sets differ substantially from the results obtained in the linear setting.

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Este proyecto estudiará las estrategias de vida implementadas por familias productoras fruti hortícolas que viven en Colonia Tirolesa y Chacra de la Merced, lugares que forman parte del cinturón verde de la Ciudad de Córdoba; y su relación con los procesos de diferenciación social, asociados a cambios productivos, económicos, culturales y sociales que están condicionados por el modelo de expansión capitalista. A partir del análisis del capital económico, social, cultural y simbólico se identificará en un contexto rural las motivaciones, logicas productivas y conocimientos agrícolas que incidieron en las decisiones asumidas ante problematicas emergentes, tales como limitaciones para adquirir nuevos paquetes tecnológicos, el impacto ambiental causados por la no conservación y sustentabilidad de los recursos y las consecuencias sociales vinculadas a los laxos de familia, el trabajo y la calidad de vida.Se plantean las siguientes hipótesis: 1)Algunas familias productoras implementaron estrategias de vida que se relacionan con criterios de autosustentabilidad, conocimientos agrícolas tradicionales y pautas culturales.2) Los nuevos espacios productivos no son compatibles con agroecosistemas sustentables. 3) Las nuevas tecnologías causaron impactos en la actividad productiva e incidieron en la economía, calidad de vida y vinculos familiares. 4)El modo de producción familiar fue reemplazado por el modo de producción capitalista lo que incidió en la producción agrícola y en la conservación de los recursos.El objetivo principal es descubrir las estrategias de vida implementadas por un grupo de familias, trabajadoras fruti hortícolas, en respuesta a las transformaciones productivas, tecnológicas y socio económicas impuestas por el modelo de acumulación vigente.Para ello se caracterizará los ambitos productivos de trabajo a campo, identificando la disponibilidad de capital y los conocimientos técnicos y de manejo. También se analizarán las pautas y valores culturales, el impacto de las nuevas tecnologías y la incidencia social, vinculada a los cambios en los modos de producción.El abordaje será de tipo cualitativo, recavando información para elaborar una descripción detallada de las estrategias de vida adoptadas a partir de la década de los noventa. Se tomará como unidad de análisis a las familias que trabajaron o trabajan en la producción de hortalizas o frutales. Se realizarán combinaciones entre procedimientos Tipológicos a Priori; Históricos Comparativos y casos Unitarios. Se analizará las normativas vigentes en relación al uso y calidad del agua y del suelo; también imágenes satelitales para analizar los procesos de cambio en el uso del territorio y del recurso suelo. Se pretende realizar un aporte relacionado con el conocimiento de: la sustentabilidad de los sistemas productivos, la pobreza y los modos de vida de los productores fruti hortícolas que persistencia en ambientes degradados; en una franja intermedia entre el campo y la ciudad.

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This thesis presents the research and development of sustainable design guidelines for the furniture and wood products industry, suitable for sustainably enhancing design, manufacturing and associated activities. This sustainable guideline is based on secondary research conducted on subject areas such as ‘eco’ design, ‘green’ branding and ‘green’ consumerism, as well as an examination of existing certifications and sustainable tools techniques and methodologies, national and international drivers for sustainable development and an overview of sustainability in the Irish furniture manufacturing context. The guideline was further developed through primary research. This consisted of a focus group attended by leading Irish designers, manufacturers and academics in the area of furniture and wood products. This group explored the question of ‘green branding’ saturation in the market and the viability of investing in sustainability just yet. Participants stated that they felt the market for ‘green’ products is evolving very slowly and that there is no metric or legal framework present to audit whether or not companies are producing products that really embody sustainability. All the participants believed that developing and introducing a new certification process to incorporate a sustainable design process was a viable and necessary solution to protecting Irish furniture and wood manufacturers going forward. For the purposes of the case study, the author investigated a ‘sustainable’ design process for Team woodcraft, Ltd., through the design and development of a ‘sustainable’ children’s furniture range. The case study followed a typical design and development process; detailing customer design specifications, concept development and refinement and cumulating in final prototype, as well as associated engineering drawings. Based on this primary and secondary research, seven fundamental core principles for this sustainable guideline have been identified by the author. The author then used these core principles to expand into guidelines for the basis of proposed new Irish sustainable design guidelines for the furniture and wood products industry, the concept of which the author has named ‘Green Dot’. The author suggests that the ‘Green Dot’ brand or logo could be used to market an umbrella network of Irish furniture designers and manufactures who implement the recommended sustainable techniques.