172 resultados para Scrap


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Halogen-containing aromatics, mainly bromine-containing phenols, are harmful compounds contaminating pyrolysis oil from electronic boards containing halogenated flame retardants. In addition, theirformation increases the potential for evolution of polybrominated dibenzo-p-dioxins (PBDDs) and dibenzofurans (PBDFs) at relatively low temperature (up to 500 °C). As a model compound, 2,4-dibromophenol (DBP) was pyrolyzed at 290-450 °C. While its pyrolysis in a nitrogen flow reactor or in encapsulated ampules yields bromine-containing phenols, phenoxyphenols, PBDDs, and PBDFs, pyrolysis of DBP in a hydrogen-donating medium of polypropylene (PP) at 290-350 °C mainly results in the formation of phenol and HBr, indicating the occurrence of a facile hydrodebromination of DBP. The hydrodebromination efficiency depends on temperature, pressure, and the ratio of the initial components. This thermal behavior of DBP is compared to that of 2,4-dichlorophenol and decabromodiphenyl ether. A treatment of halogen-containing aromatics with PP offers a new perspective on the development of low-environmental-impact disposal processes for electronic scrap. © 2005 American Chemical Society.

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This paper investigates the main strategies automotive companies adopt to address the issue of dealing with end-of-life vehicles and spare parts. Furthermore, it investigates the reasons behind take-back strategies, i.e how and why automotive companies undertake initiatives in reverse logistics. The research findings indicate that companies are trying to respond to the end-of-life legislation based on cost-effective approaches as well as corporate environmental responsibility. Outsourcing is used when expertise is found to extract value from scrap and there is cooperation with suppliers and vendors to facilitate the dismantling of cars and recycling of parts.

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Five axis machine tools are increasing and becoming more popular as customers demand more complex machined parts. In high value manufacturing, the importance of machine tools in producing high accuracy products is essential. High accuracy manufacturing requires producing parts in a repeatable manner and precision in compliance to the defined design specifications. The performance of the machine tools is often affected by geometrical errors due to a variety of causes including incorrect tool offsets, errors in the centres of rotation and thermal growth. As a consequence, it can be difficult to produce highly accurate parts consistently. It is, therefore, essential to ensure that machine tools are verified in terms of their geometric and positioning accuracy. When machine tools are verified in terms of their accuracy, the resulting numerical values of positional accuracy and process capability can be used to define design for verification rules and algorithms so that machined parts can be easily produced without scrap and little or no after process measurement. In this paper the benefits of machine tool verification are listed and a case study is used to demonstrate the implementation of robust machine tool performance measurement and diagnostics using a ballbar system.

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Culturally responsive instruction refers to the identification of relevant cultural aspects of students' lives and infusion of these into the curriculum. This instructional approach assumes that a culturally appropriate curriculum can potentially motivate, engage, and lead students to higher rates of achievement. This quasi-experimental study (N=44) investigated the relationship of culturally responsive instruction and the reading comprehension and attitude of struggling urban adolescent readers. The study incorporated the use of culturally responsive instruction using culturally relevant literature (CRL), the Bluford Series Novels, as authentic texts of instruction. Participants were seventh grade reading students at a Title I middle school in South Florida. After a baseline period, two different classes were taught for 8 weeks using different methods. One class formed the experimental group ( n=22) and the other class formed the comparison group (n =22). The CRI curriculum for the experimental group embraced the socio-cultural perspective through the use of small discussion groups in which students read and constructed meaning with peers through interaction with the Bluford Series Novels; gave written responses to multiple strategies according to SCRAP - Summarize, Connect, Reflect, Ask Questions, Predict; responded to literal and inferential questions, while at the same time validating their responses through evidence from the text. The Read XL (basal reader) curriculum of the comparison group utilized a traditional form of instruction which incorporated the reading of passages followed by responses to comprehension questions, and teacher-led whole group discussion. The main sources of data were collected from the Gates-MacGinitie Reading Tests, the Florida Assessments for Instruction in Reading (FAIR), and the Rhody Secondary Reading Attitude Assessment. Statistical analyses were performed using Repeated Measures ANOVAs. Findings from the study revealed that the experimental participants' reading attitudes and FAIR comprehension scores increased when compared to the comparison group. Overall, the results from the study revealed that culturally responsive instruction can potentially foster reading comprehension and a more positive attitude towards reading. However, a replication of this study in other settings with a larger, more randomized sample size and a greater ethnic variation is needed in order to make full generalizations.

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The field of experience and reflection in this dissertation is the Pau and Lata: Artisticpedagogical project and its activities in the field of music education It was created in 1996, by the Community School Sementes da Luz, located on Tabuleiro do Martins district, Maceió / AL. The work extended to the Rio Grande do Norte and later returned to Alagoas, keeping their activities in both states, involving approximately 280 people. The issues that moved us front the experience of Pau e Lata were: What are the main references and theoretical-methodological elements that constitute the formation of the musician in Pau e Lata? How members perceive this project and include themselves in the educational process of music formation? How it works and what is the meaning of the use of instruments and the learning of musical writing and reading? These questions lead us to undertake this dissertation, in order to deepen reflection on the processes of musical training on Pau e Lata, relating the experiences of its members in the process and the theoretical references governing their educational practice. In this sense, we outline the research objectives, which are: describe the Pau e Lata project, focusing on their context of action and their methodological processes; investigate the relationship between the effective participation of its members in the process of composition of the artistic and pedagogical repertoire and its performance in the field of cultural militancy in the environment where it operates. The writing process of this research is based on the phenomenological perspective. Therefore constitute our methodological research path two roads that communicate: 1) the organization and description of historical record of Pau e Lata (supporting documents, certificates, posters, etc.) and memories of the researcher and from other members of the group. 2) the formation of focal groups and writing and sending, via online, testimonials the participants of Pau and Lata relating to issues scrap and onomatopoeia, respectively. Participated in this process 11 components, adding the presence of the researcher, with the age between 21-45 years, all members of Pau e Lata, Core UFRN. The results of this research are focused on the discussion of three axes that describe and guide the work of the Pau e Lata: collective work, the use of the scrap as instrument and the onomatopoeia as base of a methodological process of musical training. This score was composed of three parts. The first part is presented from a collection of references from Pau e Lata, composed of printed and videographic records. The second part refers to the instrument used by Pau e Lata, and the perception of group members on these instruments, which occurs so that they are integrated in the training of the musician.The third axis tells how and what it means learning of music writing and reading, that occurs in two related aspects: the teaching-learning process and the body as a musical element in this process, associated with other actions characterized as studies and theoretical deepening

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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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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 recuperação de metais a partir de resíduos é uma actividade ligada à valorização de resíduos que se afigura essencial à preservação de recursos naturais. O tratamento de resíduos metálicos é essencial para o sucesso da reciclagem. O tratamento permite diminuir contaminações com outros materiais, melhorar a valorização e diminuir os custos de transporte. Ao tratamento encontram-se associadas diferentes operações, cuja finalidade é preparar os metais de acordo com os requisitos de processo dos recicladores. A fragmentação é uma das operações de pré-tratamento mais relevantes pela sua capacidade de processamento e pela possibilidade de permitir separar resíduos contaminados com outros materiais. O presente trabalho efectua uma análise inicial ao sector e às tecnologias existentes permitindo introduzir posteriormente o caso de estudo, a instalação em Vila Nova de Gaia da empresa Constantino Fernandes Oliveira & Filhos, SA. O enfoque ao caso de estudo aborda o tema da eficiência energética, um dos principais custos de produção. Nesta perspectiva identifica pontos críticos e estabelece medidas de eficiência energética que permitam reduzir o consumo energético. As medidas propostas foram a colocação de um variador electrónico de velocidade no ventilador principal da fragmentadora e no compressor e a substituição da iluminação existente por iluminação LED. As medidas propostas permitem a redução do consumo específico de energia de 9,39 kgep/t para 8,81 kgep/t. Sendo a fragmentação uma das operações mais relevantes na actividade da instalação estudada, no presente trabalho, efectuou-se a análise do modelo operatório com recurso à aplicação STAN de análise de fluxos de materiais. O procedimento de análise envolveu a criação de vários cenários de exploração no tratamento de resíduos. O objectivo das simulações é a contabilização dos custos referentes ao tratamento dos resíduos permitindo melhorias na vertente operacional, ambiental e económica. Um dos cenários simulados foi a remoção dos veículos em fim de vida dos resíduos a fragmentar, onde se constatou que apesar de uma redução dos resíduos processados, os proveitos por quantidade processada não alteram relativamente ao modelo operatório de base. Este facto deve-se sobretudo aos custos elevados de tratamento de resíduos gerados no processo de fragmentação dos veículos em fim de vida.

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The Recycling Market Development Advisory Council is comprised of 14 governor-appointed members representing the recycling industry, government, higher education, solid waste industry and citizen affiliations. The Council is staffed by the South Carolina Department of Commerce. This report also provides information on RMDAC’s work plan, economic development data, resources and market information for the glass, paper, plastics, scrap tires, used oil, nonferrous aluminum and ferrous scrap metal industries.

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The Recycling Market Development Advisory Council is comprised of 14 governor-appointed members representing the recycling industry, government, higher education, solid waste industry and citizen affiliations. The Council is staffed by the South Carolina Department of Commerce. This report also provides information on RMDAC’s work plan, economic development data, resources and market information for the glass, paper, plastics, scrap tires, used oil, nonferrous aluminum and ferrous scrap metal industries.

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The Recycling Market Development Advisory Council is comprised of 14 governor-appointed members representing the recycling industry, government, higher education, solid waste industry and citizen affiliations. The Council is staffed by the South Carolina Department of Commerce. This report also provides information on RMDAC’s work plan, economic development data, resources and market information for the glass, paper, plastics, scrap tires, used oil, nonferrous aluminum and ferrous scrap metal industries.

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The Recycling Market Development Advisory Council is comprised of 14 governor-appointed members representing the recycling industry, government, higher education, solid waste industry and citizen affiliations. The Council is staffed by the South Carolina Department of Commerce. This report also provides information on RMDAC’s work plan, economic development data, resources and market information for the glass, paper, plastics, scrap tires, used oil, nonferrous aluminum and ferrous scrap metal industries.

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The Recycling Market Development Advisory Council is comprised of 14 governor-appointed members representing the recycling industry, government, higher education, solid waste industry and citizen affiliations. The Council is staffed by the South Carolina Department of Commerce. This report also provides information on RMDAC’s work plan, economic development data, resources and market information for the glass, paper, plastics, scrap tires, used oil, nonferrous aluminum and ferrous scrap metal industries.

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The Recycling Market Development Advisory Council is comprised of 14 governor-appointed members representing the recycling industry, government, higher education, solid waste industry and citizen affiliations. The Council is staffed by the South Carolina Department of Commerce. This report also provides information on RMDAC’s work plan, economic development data, resources and market information for the glass, paper, plastics, scrap tires, used oil, nonferrous aluminum and ferrous scrap metal industries.

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The Recycling Market Development Advisory Council is comprised of 14 governor-appointed members representing the recycling industry, government, higher education, solid waste industry and citizen affiliations. The Council is staffed by the South Carolina Department of Commerce. This report also provides information on RMDAC’s work plan, economic development data, resources and market information for the glass, paper, plastics, scrap tires, used oil, nonferrous aluminum and ferrous scrap metal industries.