Made available in DSpace on 2014-06-11T19:24:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-02-17Bitstream added on 2014-06-13T19:06:29Z : No. of bitstreams: 1 zhu_nxj_me_bauru.pdf: 4158261 bytes, checksum: bafc2c29b13e8c6fb309c4a1b184788a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Atualmente tem-se verificado crescente demanda por processos de fabricação capazes de produzir peças sob estreitas faixas de tolerâncias dimensionais e geométricas. Dentre os processos utilizados para conferir acabamento superficial e correção de forma destacam-se a retificação e a lapidação. Porém, muitas peças mostram-se suscetíveis ao calor gerado pela retificação, como no caso da deformação de peças delgadas ou então naquelas peças passíveis de mudanças microestruturais, recorrendo-se nestes casos à lapidação que, por sua vez, é um processo de difícil seleção de parâmetros. Neste trabalho é iniciado o desenvolvimento de um processo híbrido capaz de aliar algumas importantes características da retificação e da lapidação, no qual do primeiro é usado a operação de dressagem e do segundo o movimento cinemático. Dessa forma dotou-se uma... / Lately, one can verify that there has been a growing demand for manufacturing processes capable of producing workpieces under tight dimensional and geometric tolerance rangers. Among the processes used to assure surface finish and shape correction to the part, grinding and lapping arise as the most used. However, many parts show themselves sensitive to the heat generated during the grinding process, as in the case of thin ones, or those susceptible to micro-structural changes. On these cases, one can use lapping, even though being a more difficult parameter selection process. In these studies, the development of a hybrid process capable of binding some important grinding and lapping features is initiated; the dressing operation, for the case of grinding and, for the case of lapping, the cinematic movement... (Complete abstract click electronic access below)

Esta dissertação trata do tema desenho técnico do vestuário. O objetivo deste trabalho foi sistematizar diretrizes para a representação gráfica técnica de acabamentos, detalhes, linhas e cotas em produtos do vestuário do segmento de malharia circular com vistas à sua normalização. A pesquisa foi classificada como aplicada, qualitativa e exploratória. A coleta de dados ocorreu por meio de entrevistas semiestruturadas e coleta documental realizadas de forma presencial e por meio eletrônico (e-mail). Os participantes foram sete docentes de disciplinas de desenho técnico que atuam em instituições de ensino superior que possuem cursos de moda em nível bacharelado e, oito profissionais do desenvolvimento de produto de empresas de confecção do vestuário que trabalham com malha circular. Com isso, foi possível diagnosticar como é feita a representação de desenhos técnicos do vestuário nestes dois ambientes, o acadêmico e o industrial, localizados em diferentes regiões brasileiras. Os resultados das entrevistas foram apresentados através de quadros comparativos com cruzamento dos dados coletados. Como resultado, apresentam-se diretrizes para a construção do desenho e representação de cores, linhas, cotas/medidas. Outro produto deste trabalho é um catálogo dos principais acabamentos e detalhes utilizados em malha circular com descrições, imagens e representações técnicas dos mesmos. / This dissertation deals with the theme of technical drawing of clothing. The aim of this study was to propose guidelines for graphical representation technique of finishing, details, lines and quotas on clothing products of circular knitting segment to achieve its normalization. The research was classified as applied, exploratory and qualitative. Data collection occurred through semi-structured interviews and documentary collection both conducted face-to-face form and by electronic means (e-mail). Participants consisted of seven professors of technical drawing disciplines who work in institutions of higher education that have fashion courses in the Bachelor level. In addition to the professors, eight product development professionals of knitting clothing companies who work with circular mesh also participated. With this, it was possible to diagnose how is the representation of technical drawings of clothing in these two environments, the academic and the industrial, located in different regions of Brazil. The interview responses were presented through comparative tables including the collected data. As a result, guidelines are presented for the construction of the drawing and representation of colors, lines, dimensions/measurements. Another product of this work is a catalogue of the main finishing and details used in circular knit with descriptions, images and representations of the referred techniques.

Esta dissertação trata do tema desenho técnico do vestuário. O objetivo deste trabalho foi sistematizar diretrizes para a representação gráfica técnica de acabamentos, detalhes, linhas e cotas em produtos do vestuário do segmento de malharia circular com vistas à sua normalização. A pesquisa foi classificada como aplicada, qualitativa e exploratória. A coleta de dados ocorreu por meio de entrevistas semiestruturadas e coleta documental realizadas de forma presencial e por meio eletrônico (e-mail). Os participantes foram sete docentes de disciplinas de desenho técnico que atuam em instituições de ensino superior que possuem cursos de moda em nível bacharelado e, oito profissionais do desenvolvimento de produto de empresas de confecção do vestuário que trabalham com malha circular. Com isso, foi possível diagnosticar como é feita a representação de desenhos técnicos do vestuário nestes dois ambientes, o acadêmico e o industrial, localizados em diferentes regiões brasileiras. Os resultados das entrevistas foram apresentados através de quadros comparativos com cruzamento dos dados coletados. Como resultado, apresentam-se diretrizes para a construção do desenho e representação de cores, linhas, cotas/medidas. Outro produto deste trabalho é um catálogo dos principais acabamentos e detalhes utilizados em malha circular com descrições, imagens e representações técnicas dos mesmos. / This dissertation deals with the theme of technical drawing of clothing. The aim of this study was to propose guidelines for graphical representation technique of finishing, details, lines and quotas on clothing products of circular knitting segment to achieve its normalization. The research was classified as applied, exploratory and qualitative. Data collection occurred through semi-structured interviews and documentary collection both conducted face-to-face form and by electronic means (e-mail). Participants consisted of seven professors of technical drawing disciplines who work in institutions of higher education that have fashion courses in the Bachelor level. In addition to the professors, eight product development professionals of knitting clothing companies who work with circular mesh also participated. With this, it was possible to diagnose how is the representation of technical drawings of clothing in these two environments, the academic and the industrial, located in different regions of Brazil. The interview responses were presented through comparative tables including the collected data. As a result, guidelines are presented for the construction of the drawing and representation of colors, lines, dimensions/measurements. Another product of this work is a catalogue of the main finishing and details used in circular knit with descriptions, images and representations of the referred techniques.

Este trabalho discute as alterações micro-estruturais superficiais nos aços usinados por torneamento duro. Uma estrutura não aceita metalurgicamente, chamada de Camada Branca (\"White Layer\" - WL), é freqüentemente encontrada na superfície torneada. A presença desta camada branca depende dos parâmetros do processo de corte, especialmente do desgaste da ferramenta e da velocidade do corte. A formação da camada branca foi investigada no presente trabalho na face plana inferior de um anel de rolamento fabricada com o aço DIN 100Cr6, usinada por torneamento duro no estado temperado e revenido (dureza 60HRC). A profundidade foi medida usando as técnicas padrões metalográficas. As propriedades mecânicas da camada superficial (módulo de rigidez, E, e microdureza Vickers, HV) foram estimadas pelo método de microidentação instrumentada em uma amostra isenta da camada branca e em duas outras amostras, com camadas brancas de diferentes espessuras (respectivamente 7 e 12 mm de espessura). De acordo com a literatura a profundidade da camada branca aumenta de acordo com o desgaste da aresta da ferramenta. Este por sua vez aumenta com a velocidade de corte, mas atinge a saturação. Em outras palavras, a profundidade de corte tem pouco efeito sobre a profundidade da camada branca; porém aumentando o avanço da ferramenta de corte ocorre o aparecimento da mesma. Os presentes resultados confirmam um efeito do avanço da ferramenta sobre a espessura da WL, tal que quanto menor o avanço, maior é a espessura, porém não confirmam o efeito do desgaste da ferramenta. A formação desta camada é discutida no contexto da sua influência sobre a rugosidade das peças. / This work deals with the microstructural changes in the surface of steels machined by hard turning. A non-acceptable microstructure, called White Layer - WL, is usually found in the hard turned surface. The presence of the white layer depends on hard turning parameters, especially on the wear of the machining tool and cutting speed. The formation of the white layer was investigated in the present work by hard turning the inferior face of a roller-bearing ring fabricated with DIN 100Cr6 steel quenched and tempered (60 HRC hardness). The depth of the WL was measured by standard metallographic procedures. The mechanical properties (stiffness modulus, E, and Vickers hardness) of the surface layer were measured by intrumented indentation in three samples: one with no WL, and two containing a WL of respectively 7 and 12 mm. According to the literature the depth of the WL increases with the wear of the machining tool. This increased with cutting speed, but reaches saturation. The presentresults confirm an effect of tool advance upon the depth of the WL, such that decreasing the advance leads to an increase in its depth, but an effect of tool wear could not be recognized. The formation of the WL is discussed in the context of its effect on surface roughness.

A thesis submitted in partial fulfillment of the academic requirements for the Degree of M-Tech in Chemical Engineering, Durban University of Technology Durban, 2008. / The waste generated by metal finishers is rated as the most toxic and harmful to the environment. Metal finishing wastewater consists of heavy metals, cyanides, acids and alkalis. Formal treatment of waste generated has not been of primary importance to metal finishers. It would be ideal to develop a generic model to assist finishers to predict the effectiveness of wastewater treatment. The model must be able to predict effectiveness of treatment based on a variety of equipment, chemicals and concentrations. / M

Esta dissertação trata do tema desenho técnico do vestuário. O objetivo deste trabalho foi sistematizar diretrizes para a representação gráfica técnica de acabamentos, detalhes, linhas e cotas em produtos do vestuário do segmento de malharia circular com vistas à sua normalização. A pesquisa foi classificada como aplicada, qualitativa e exploratória. A coleta de dados ocorreu por meio de entrevistas semiestruturadas e coleta documental realizadas de forma presencial e por meio eletrônico (e-mail). Os participantes foram sete docentes de disciplinas de desenho técnico que atuam em instituições de ensino superior que possuem cursos de moda em nível bacharelado e, oito profissionais do desenvolvimento de produto de empresas de confecção do vestuário que trabalham com malha circular. Com isso, foi possível diagnosticar como é feita a representação de desenhos técnicos do vestuário nestes dois ambientes, o acadêmico e o industrial, localizados em diferentes regiões brasileiras. Os resultados das entrevistas foram apresentados através de quadros comparativos com cruzamento dos dados coletados. Como resultado, apresentam-se diretrizes para a construção do desenho e representação de cores, linhas, cotas/medidas. Outro produto deste trabalho é um catálogo dos principais acabamentos e detalhes utilizados em malha circular com descrições, imagens e representações técnicas dos mesmos. / This dissertation deals with the theme of technical drawing of clothing. The aim of this study was to propose guidelines for graphical representation technique of finishing, details, lines and quotas on clothing products of circular knitting segment to achieve its normalization. The research was classified as applied, exploratory and qualitative. Data collection occurred through semi-structured interviews and documentary collection both conducted face-to-face form and by electronic means (e-mail). Participants consisted of seven professors of technical drawing disciplines who work in institutions of higher education that have fashion courses in the Bachelor level. In addition to the professors, eight product development professionals of knitting clothing companies who work with circular mesh also participated. With this, it was possible to diagnose how is the representation of technical drawings of clothing in these two environments, the academic and the industrial, located in different regions of Brazil. The interview responses were presented through comparative tables including the collected data. As a result, guidelines are presented for the construction of the drawing and representation of colors, lines, dimensions/measurements. Another product of this work is a catalogue of the main finishing and details used in circular knit with descriptions, images and representations of the referred techniques.

Objective: To assess the effect of finishing and polishing direction on the marginal adaptation of resin-based composite restorations. Methods: Forty human molars were collected and sectioned along their mesio-distal axis. Buccal and lingual enamel surfaces were flattened and a triangular preparation (0.87mm deep and 3mm wide) representing two 30° bevels was achieved. Specimens (n=20/per group) were randomly assigned in groups and restored with two resin-based composite materials: a nanofilled (Filtek Supreme Ultra)(FSU) and a microhybrid (Point4)(PT4) and two finishing/polishing techniques: a series of Sof-Lex discs (SL) and a sequence of diamond bur/dark-orange SL/rubber polishers (HiLuster). On each specimen, both margins were finished and polished with the same technique, one from the resin-based composite to the tooth structure (C-T) and the other from the tooth structure to the resin-based composite (T-C). Replicas were made for FeSEM observation (200X) and quantitative margin analysis was performed based on four defined marginal quality criteria. Comparisons were made between polishing directions (paired-samples t-test, Wilcoxon signed-rank test), between resin-based composites and between polishing techniques (two-sample t-test and Wilcoxon rank sum test) Results: Significant differences were found between polishing directions (p<0.05). Data showed more continuous margins, less marginal irregularities and less gaps with the polishing direction C-T than T-C except for one group (FSU/SL) with marginally significant difference in gaps (p=0.0537). Differences between the two resin-based composites and the two polishing techniques seemed to be dependent on certain combinations of resin-based composite, polishing technique and polishing direction. Conclusion: Within the limitations of this in vitro study, polishing from resin-based composite to tooth structure (C-T) leads to better marginal adaptation than polishing from tooth structure to resin-based composite (T-C).

This dissertation concerns the development of simulation and optimization technology for industrial, hydrolytic nylon-6 polymerizations. The significance of this work is that it is a comprehensive and fundamental analysis of nearly all of the pertinent aspects of simulation. It steps through all of the major steps for developing process models, including simulation of the reaction kinetics, phase equilibrium, physical properties, and mass-transfer- limited devolatization. Using this work, we can build accurate models for all major processing equipment involved in nylon-6 production. Contributions in this dissertation are of two types. Type one concerns the formalization of existing knowledge of nylon-6 polymerization mixtures, mainly for documentation and teaching purposes. Type two, on the other hand, concerns original research contributions. Formalizations of existing knowledge include reaction kinetics and physical properties. Original research contributions include models for phase equilibrium, diffusivities of water and caprolactam, and devolatization in vacuum-finishing reactors. We have designed all of the models herein to be fundamental, yet accessible to the practicing engineer. All of the analysis was done using commercial software packages offered by Aspen Technology, Cambridge, MA. We chose these packages for two reasons: (1) These packages enable one to quickly build fundamental steady-state and dynamic models of polymer trains; and (2) These packages are the only ones commercially available for simulating polymer trains. / Ph. D.

The excellent particulate removal efficiency of ceramic candle filters has prompted efforts to develop a more durable and economical alternative to existing ceramic candle filters. Porous ceramic candle filter elements were successfully fabricated from calcium aluminate cement, calcined fireclay aggregate, and organic pore formers using refractory concrete casting techniques. Methods used to characterize the porous ceramic filter elements included determination of pore size and distribution, permeability, resistance to alkali attack, and mechanical strength. Various pore formers and casting, curing, and sintering conditions were examined to produce highly permeable and structurally sound filter elements. The optimized fabrication procedure produced porous ceramic candle filter elements with pore diameters between 20.3 to 43.1 tlm, porosities of 38 to 60%, and pressure drops of 3 to 24 mbars at a face velocity of 100 mjh. These characteristics are comparable to existing ceramic filters which are noted for their > 99% collection efficiencies of submicrometer-sized particles, but short-term durability in advanced coal combustion clean-up systems. Test specimens of the alumino silicate refractory concrete proved more durable by showing no severe attack following exposures to alkali-containing atmospheres at 700-1000°C. The strength of the cast samples ranged from 200 to 1139 psi depending on the relative densities and pore formers. Porous fliter elements with different porous structures, permeabilities, and shapes can be easily produced with this technique. / Master of Science

Ethoxyl capped hydroxypropyl lignin (IIP-EL) was used as a finishing agent for cotton fabric to impart the property of crease recovery to the fabric. The synthesis of the finish involved two steps: Synthesis of phenyl N( 3 - cyanato 4 methyl phenyl) carbamate by reacting phenol and Tolylene diisocyanate (TDI) in a 1:1 mole ratio. Reaction of the above prepolymer with the modified lignin (HP- EL) using a mole ratio of 1:20 to form a lignin carbamate. The lignin carbamate finish was crosslinked to cotton cellulose fabric through carbamoyl linkages when the fabric was cured. There is emperical evidence for the chemical crosslinking of cellulose with lignin. The effects of the finish on the fabric physical properties like durable press rating, dimensional stability, tensile strength, abrasion resistance, warp and weft recovery angle were investigated. Analysis of the results showed improvement in the durable press rating and excellent retention of tensile strength and abrasion resistance. The results of warp and weft recovery angle tests which relate to durable press properties, suggest the need to further investigate the possibility of using a different chain-extended lignin to achieve improved results. / Master of Science