994 resultados para industrial residue


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The ceramics industry generates waste at various stages of that process, defective products, waste from burning solid fuels, among others. This waste is dumped in landfills, garbage dumps or directly on roads, which has a negative environmental impact. This paper presents a study to incorporate the waste of algaroba wood and chamote (scrap pieces of ceramic already sintered), in to the ceramic material for making sealing blocks. The methodological procedures consist in the characterization of chemical and mineralogical residues, raw materials, and physical-mechanical of the formulations of mixes with clay, silt and waste. By pressing test pieces were produced using a pressure of 200 kgf/cm², varying compositions in the range of 0%, 5%, 10% and 15% by weight of residue. The sintering was performed in a muffle furnace, with the temperature levels of 850 ° C, 900 ° C, 950 ° C, 1000 ° C and 1050 ° C. The evaluated physical and mechanical properties were: Water Absorption, Linear Shrinkage Burning, Apparent Porosity, Apparent Density and Mechanical Resistance to Flexion. Analysis was carried out by Scanning Electron Microscopy on fracture surfaces of the specimens. Evaluation of linear shrinkage property drying and firing , water absorption and mechanical resistance to compression of the sealing blocks 5% wood ash residue, sintered at 900 °C hold temperature in the laboratory the products manufactured on an industrial scale. The main results, it was found on the viability of using the residues of algaroba wood and to confer refractory properties of the ceramic product. The main results, it was concluded feasibility of using the ash residues algaroba wood to impart refractory properties to the ceramic product and the residue of chamote, being derived from the own ceramic product not interfere with the properties, when used in a percentage of up to 5%.Since the residue of chamote being derived from the ceramic product itself had no effect on the properties. Studies in the laboratory have shown that the incorporation of up to 5% of these residues may be adopted as an alternative technology to reduce the environmental impact caused by the industrial sector, without compromising the final properties of the material, since the results on an industrial scale showed absorption values 11.66 and 11.74 of water and waste products respectively, within the parameters of NBR - 15,270, since the mechanical strength was 1.25 MPa and 0.94 MPa respectively for products with and without residue, lower than the minimum required by the technical standard that is 1.5 MPa.

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A multi-residue gas chromatography-mass spectrometry method was developed in order to evaluate the presence of 39 pesticides of different chemical families (organophosphorus, triazines, imidazole, organochlorine), as well as some of their transformation products, in surface water samples from Ria de Aveiro. Ria de Aveiro is an estuarine coastal lagoon, located in the northern west region of Portugal, which receives inputs from agriculture, urban and industrial activities. The analytical method was developed and validated according international guidelines and showed good linearity, with correlation coefficients higher than 0.9949 for all compounds, adequate precision and accuracy, and high sensitivity. Pesticides were chosen from the priority pollutants list of the Directive 2008/105/EC of the European Parliament and of the Council (on environmental quality standards in the field of water policy), or were selected due their common use in agricultural practices. Some of these 39 pesticides are, or are suspected to be, endocrine disruptor compounds (EDCs), being capable of altering the endocrine system of wildlife and humans, causing form malfunction and ultimately health problems. Even those pesticides which are not EDCs, are known to be awfully toxic and have a recognised impact in human health. The aquatic environment is particularly susceptible to pollution due to intentional and accidental release of chemicals to water [3]. Pesticide contamination of surface water is a national issue as it is often used as drinking water. This concern is especially important in rural agricultural areas where population uses small private water supplies, regularly without any laboratory surveillance. The study was performed in seven sampling points and the results showed a considerable concern pesticide contamination of all samples.

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L'industrie du ciment est l'une des principales sources d'émission de dioxyde de carbone. L'industrie mondiale du ciment contribue à environ 7% des émissions de gaz à effet de serre dans l'atmosphère. Afin d'aborder les effets environnementaux associés à la fabrication de ciment exploitant en permanence les ressources naturelles, il est nécessaire de développer des liants alternatifs pour fabriquer du béton durable. Ainsi, de nombreux sous-produits industriels ont été utilisés pour remplacer partiellement le ciment dans le béton afin de générer plus d'économie et de durabilité. La performance d'un additif de ciment est dans la cinétique d'hydratation et de la synergie entre les additions et de ciment Portland. Dans ce projet, deux sous-produits industriels sont étudiés comme des matériaux cimentaires alternatifs: le résidu de silice amorphe (RSA) et les cendres des boues de désencrage. Le RSA est un sous-produit de la production de magnésium provenant de l'Alliance Magnésium des villes d'Asbestos et Thedford Mines, et les cendres des boues de désencrage est un sous-produit de la combustion des boues de désencrage, l'écorce et les résidus de bois dans le système à lit fluidisé de l'usine de Brompton située près de Sherbrooke, Québec, Canada. Récemment, les cendres des boues de désencrage ont été utilisées comme des matériaux cimentaires alternatifs. L'utilisation de ces cendres comme matériau cimentaire dans la fabrication du béton conduit à réduire la qualité des bétons. Ces problèmes sont causés par des produits d'hydratation perturbateurs des cendres volantes de la biomasse quand ces cendres sont partiellement mélangées avec du ciment dans la fabrication du béton. Le processus de pré-mouillage de la cendre de boue de désencrage avant la fabrication du béton réduit les produits d'hydratation perturbateurs et par conséquent les propriétés mécaniques du béton sont améliorées. Les approches pour étudier la cendre de boue de désencrage dans ce projet sont : 1) caractérisation de cette cendre volante régulière et pré-humidifiée, 2) l'étude de la performance du mortier et du béton incorporant cette cendre volante régulière et pré-humidifiée. Le RSA est un nouveau sous-produit industriel. La haute teneur en silice amorphe en RSA est un excellent potentiel en tant que matériau cimentaire dans le béton. Dans ce projet, l'évaluation des RSA comme matériaux cimentaires alternatifs compose trois étapes. Tout d'abord, la caractérisation par la détermination des propriétés minéralogiques, physiques et chimiques des RSA, ensuite, l'optimisation du taux de remplacement du ciment par le RSA dans le mortier, et enfin l'évaluation du RSA en remplacement partiel du ciment dans différents types de béton dans le système binaire et ternaire. Cette étude a révélé que le béton de haute performance (BHP) incorporant le RSA a montré des propriétés mécaniques et la durabilité, similaire du contrôle. Le RSA a amélioré les propriétés des mécaniques et la durabilité du béton ordinaire (BO). Le béton autoplaçant (BAP) incorporant le RSA est stable, homogène et a montré de bonnes propriétés mécaniques et la durabilité. Le RSA avait une bonne synergie en combinaison de liant ternaire avec d'autres matériaux cimentaires supplémentaires. Cette étude a montré que le RSA peut être utilisé comme nouveaux matériaux cimentaires dans le béton.

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Ethnography has gained wide acceptance in the industrial design profession and curriculum as a means of understanding the user. However, there is considerable confusion about the particularities of its practice accompanied by the absence of an interoperable vocabulary. The consequent interdisciplinary effort is a power play between disciplines whereby the methodological view of ethnography marginalises its theoretical and analytical components. In doing so, it restricts the potential of ethnography suggesting the need for alternative methods of informing the design process. This article suggests that activity theory, with an emphasis on human activity as the fundamental unit of study, is an appropriate methodology for the generation of user requirements. The process is illustrated through the adaptation of an ethnographic case study, for the design of classroom furniture in India.

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There is a large and growing body of research to show that human resource (HR) practices affect individual performance, organisational productivity and organisational performance. Academic findings about effective HR practices, however, have not readily been adopted by practitioners. A variety of theoretical and practical explanations have been advanced about the research-practice gap. Research by Rynes, Colbert, and Brown (2002) suggested that the research-practice gap is due to a lack of knowledge, but the extent to which these findings apply to the Australian context is unknown. The sample consisted of 102 industrial/organisational (I/O) psychologists and 89 HR practitioners. The main aim of the present study was to replicate and extend the work of Rynes et al. by examining and comparing the knowledge of I/O psychologists and HR practitioners. It was found that overall I/O psychologists were better informed about HR research than HR practitioners; in particular, they were more knowledgeable about management practices and recruitment and selection. In both groups, of the five content areas examined (Management Practices; General Employment Practices; Training and Development; Recruitment and Selection; and Compensation and Benefits), the greatest gaps were in Recruitment and Selection.

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A simple mimetic of a heparan sulfate disaccharide sequence that binds to the growth factors FGF-1 and FGF-2 was synthesized by coupling a 2-azido-2-deoxy-D-glucosyl trichloroacetimidate donor with a 1,6-anhydro-2-azido-2-deoxy--D-glucose acceptor. Both the donor and acceptor were obtained from a common intermediate readily obtained from D-glucal. Molecular docking calculations showed that the predicted locations of the disaccharide sulfo groups in the binding site of FGF-1 and FGF-2 are similar to the positions observed for co-crystallized heparin-derived oligosaccharides obtained from published crystal structures.