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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Efeito da vaporiza??o e impregna??o de nanopart?culas nas vari?veis do processo de secagem da madeira de Eucalyptus pellita F Muell / Effect of Vaporization and Impregnation of Nanoparticles on the variables of the drying process of Eucalyptus pellita F Muell

Pace, Jos? Henrique Camargo 24 February 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-10-16T12:49:06Z No. of bitstreams: 1 2016 - Jos? Henrique Camargo Pace.pdf: 2091527 bytes, checksum: ecdf1580f5a32680699ae7f0489c44fb (MD5) / Made available in DSpace on 2017-10-16T12:49:06Z (GMT). No. of bitstreams: 1 2016 - Jos? Henrique Camargo Pace.pdf: 2091527 bytes, checksum: ecdf1580f5a32680699ae7f0489c44fb (MD5) Previous issue date: 2016-02-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The aim of this study was to evaluate the effect of steaming and impregnation of nano silver particle, the drying rate of Eucalyptus pellita. The effect of the treatments was evaluated on wood in three different radial regions (inward heartwood (CIN), Intermediate heartwood (CIT) and external (TCA)). Two steaming time (12 and 24h) and soaking the wood in nanoparticle solution silver with or without application of vacuum were investigated. The effect of these treatments were assessed using the anatomical analysis (area and vessel diameter), chemical (content of extractives) and physical (density and permeability to gas) of the timber. The drying process was carried out in a climatized room with a temperature of 20 ? C ? 2 and relative humidity 65% ? 5. The analysis rate of drying was targets in humidity levels before and after the fiber saturation point (FSP). The results show that the treatments did not affect the density and area and vessel diameter. The vaporization for 24 h caused a decrease in the extractives content and an increase in permeability to gas within and between three radial regions of the wood. This results contributed to that gains in drying rate before and after the FSP were obtained. In general, the impregnating silver nanoparticles in the timber, through the two immersion methods have not yielded significant results in drying rate, except when combined with the prior application of steam (24 hours) and vacuum in the outer radial region / O objetivo desse estudo foi avaliar o efeito da vaporiza??o e da impregna??o de nano part?culas de prata nas vari?veis do processo de secagem da madeira de E. pellita. O efeito dos tratamentos foi avaliado na madeira de tr?s distintas regi?es radiais (Cerne Interno (CIN), Cerne Intermedi?rio (CIT) e Externa (TCA). Dois tempos de vaporiza??o (12 e 24 hs) e imers?o da madeira em solu??o de nanopart?culas de prata com e sem aplica??o pr?via de v?cuo foram estudados. O efeito desses tratamentos foram avaliados atrav?s de an?lises anat?micas (?rea e di?metro de vaso), qu?micas (teor de extrativos totais) e f?sicas (densidade e permeabilidade a g?s) da madeira. O processo de secagem se deu em ambiente climatizado com temperaturas de 20?C ?2 e umidades relativas de 65%?5. A an?lise da taxa de secagem foi realizada em faixas de umidade antes e depois do ponto de satura??o das fibras (PSF). Os resultados mostram que os tratamentos n?o afetaram a densidade e a ?rea e di?metro dos vasos. A vaporiza??o por 24 h promoveu um decr?scimo no teor de extrativos e um aumento na permeabilidade ? g?s dentro e entre as tr?s regi?es radiais da madeira. Esse resultados contribuiu para que ganhos na taxa de secagem antes e depois do PSF fossem obtidos. Em geral a impregna??o de nanopart?culas de prata na madeira, atrav?s dos dois m?todos de imers?o, n?o produziram resultados significativos na taxa de secagem, exceto quando combinada com a aplica??o pr?via de vapor (24 hs) e v?cuo na regi?o radial mais externa

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