55 research outputs found

    Influência das tensões de crescimento e da poda sobre a qualidade da madeira de Eucalyptus dunnii, Eucalyptus grandis e Eucalyptus saligna

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    Orientador : Prof. Dr. Jorge Luis Monteiro de MatosCoorientador: Prof. Dr. Marcio Pereira RochaCoorientador : Prof. Dr. José Guilherme PrataTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Engenharia Florestal. Defesa: Curitiba, 12/12/2014Inclui referênciasÁrea de concentração : Tecnologia e utilização de produtos florestaisResumo: No Brasil, as espécies do gênero Eucalyptus são as mais plantadas, sendo amplamente empregadas em diversos setores de base florestal e madeireira. Um dos problemas encontrados no uso da madeira para obtenção de produtos sólidos são as tensões de crescimento e a presença de nós. Neste contexto, a presente pesquisa teve como objetivo avaliar a influência das tensões de crescimento e da poda sobre a qualidade da madeira destinada à geração de produtos sólidos de espécies do gênero Eucalyptus, entre elas o Eucalyptus dunnii, Eucalyptus grandis e o Eucalytus saligna, através do uso de metodologias não destrutivas e convencionais. O material utilizado para o desenvolvimento da pesquisa foi proveniente de plantios florestais da empresa GRANFLOR, localizados na região de Rosário do Sul - RS, com 28, 40, 52 e 65 meses de idade. A avaliação da qualidade da madeira foi realizada em duas etapas: Capítulo 1: Avaliação das tensões de crescimento sobre a qualidade da madeira de Eucalyptus para geração de produtos sólidos. Neste capítulo, avaliaram-se as tensões de crescimento da madeira, através da deformação residual longitudinal (DRL), analisando, também, as variáveis de crescimento da árvore, bem como algumas propriedades físicas e mecânicas da madeira. As informações foram obtidas por métodos convencionais de acordo com normas já estabelecidas e por técnicas não destrutivas para mensuração da DRL e análise por espectroscopia de infravermelho próximo. Com base nos resultados foram realizadas analises estatísticas, com o intuito de determinar e agrupar as informações a respeito da qualidade tecnológica da madeira e suas perspectivas. Capítulo 2: Efeito da poda sobre a qualidade da madeira de Eucalyptus. Avaliou-se o sistema de poda empregado pela empresa, verificando a qualidade da cicatrização interna dos nós, bem como a extensão do núcleo nodoso e a estimativa da madeira limpa. De modo geral, os métodos utilizados, tanto convencionais quanto os não destrutivos, demostraram ser promissores e apresentaram-se como uma possível ferramenta para a caracterização da madeira. Os resultados colaboraram para a obtenção de infomações e na indicação de material que tendem a apresentar as caracterísiticas de maior interesse, visando à obtenção de uma madeira com maior valor agregado e livre de defeitos, destinada à geração de produtos sólidos. Palavras-chave: Eucalyptus. Deformação residual longitudinal. Nós. Produtos sólidos.Abstract: In Brazil, species of Eucalyptus are commonly grown, is widely employed in various sectors of based forest industries. One of the problems found in the use of wood to obtain solid products are growth stresses and the presence of knots. In this context, the present study aimed to evaluate of the influence of growth stresses and pruning on the wood quality of for the making of solid products of Eucalyptus species, among them the Eucalyptus dunnii, Eucalyptus grandis and Eucalyptus saligna using nondestructive and conventional methodologies. The material used for the development of the research came from forest plantations the GRANFLOR company located in the region of Rosário do Sul - RS, with 28, 40, 52 and 65 months of age. Evaluation wood quality was performed in two stages: Chapter 1: Evaluation of growth stress on quality of Eucalyptus wood for making of solid products. This chapter analized the growth stresses in wood by longitudinal residual strain, also analyzing the variables of tree growth, the physical and mechanical properties of wood. Information has been obtained by conventional methods according to established standards and through non-destructive techniques used to measure the longitudinal residual strain and analysis of near-infrared spectroscopy. Based on the results were performed statistical analyzes in order to determine and cluster the information about the technological quality of the wood and its perspectives. Chapter 2: Effect of pruning on quality of Eucalyptus wood. Evaluated the system of pruning employed by the company, checking the quality of the internal healing of the knots as well as the extent of the knotty core and the estimation of clear wood. In general, the methods used in both conventional and non-destructive be demonstrated promising and presented as a possible tool for characterization of timber. The results contributed to obtain information and indication of material that to present more characteristic tend to have higher interest, in order a superior wood with higher value addedand free from defects intended for making solid products. Keywords: Eucalyptus. Longitudinal residual strain. Knots. Solid products

    Resíduos da colheita florestal e do processamento da madeira na Amazônia – uma análise da cadeia produtiva

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    The sustainable management of the Amazon forest is of great importance for the conservation of the biome, minimizing ecological impacts and through the rational use of its resources, without totally destroying the habitat. An alternative sustainable forestry is the use of residues which occur during the harvesting and mechanical processing of wood. Residues from the forest are wasted, often due to not knowing how to leverage them or lack of technological options. In order to minimize waste, new technologies must be developed and employed for the use of forest residues according to local conditions, adding value to the raw material, and consequently raising the economic return and social significance, ensuring the preservation and sustainability of natural resources. The objective of this paper is the review of existing literature and the attempt to quantify residues from forest harvesting and wood processing to encourage the best use of the same.O manejo sustentável da floresta Amazônica é de grande importância para a conservação do bioma, através da utilização racional dos seus recursos, sem levar a total destruição da mesma, minimizando os impactos ecológicos. Uma alternativa de atividade florestal sustentável é o aproveitamento dos resíduos da colheita florestal e do processamento mecânico da madeira. Resíduos oriundos da floresta são desperdiçados, muitas vezes em função de não saberem aproveitá-los ou por falta de opções tecnológicas. A fim de minimizar o desperdício, novas tecnologias devem ser desenvolvidas e empregadas para o aproveitamento e utilização dos resíduos florestais conforme as condições locais, agregando valor à matéria prima, e consequentemente com retorno econômico e social significativo, assegurando a preservação e sustentabilidade dos recursos naturais. O objetivo deste trabalho é de revisar a literatura existente e tentar quantificar os resíduos florestais e da indústria da madeira para incentivar o melhor aproveitamento do mesmo

    CHEMICAL CHARACTERIZATION OF BARK COMPOUNDS FROM CAATINGA SPECIES

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    This study aimed to chemically characterize the bark extracts from three tree species: Anacardium occidentale L., Ziziphus joazeiro Mart. and Mimosa caesalpiniaefolia Benth., in addition to obtaining the soluble extract content in water, alcohol and hexane from the bark of these species. The bark was collected from branches of the three species and subsequently pre-dried and milled. The extract content was then determined using the Sohxlet method aiming to quantify the total extractives in the samples, and determine the extract content soluble in water, ethyl alcohol and hexane. The extracts were further analyzed by Near Infrared Spectroscopy (NIRS) analysis to determine their chemical composition. The extract contents in the three species behaved in a similar way, with hexane being the solvent which extracted more compounds and juazeiro the species that displayed the highest total extract content. With the chemical characterization of the extracts, it was possible to identify the presence of functional groups characteristic of carbohydrates and proteins in the aqueous extracts; the presence of characteristic hydroxyl group, for example in alcohols, aldehydes, ketones and ethers in the ethanolic extracts; and the presence of fatty acids and aromatic compounds (essential oils) in hexanolic extracts. The essential oils were the compounds which presented larger quantities, and can be exploited by the pharmaco-chemical industry

    PATTERNS OF SEED DISPERSAL SYNDROMES AT DIFFERENT ALTITUDES IN THE SEMIARID REGION

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    The objective of this study was to assess the patterns of seed dispersal syndromes of woody plants from nine forest fragments distributed at different altitude levels on the Araripe plateau, in Pernambuco, Brazil. For data collection, we divided the altitudes within the region into three categories: lower level (altitudes ≤600 m); intermediate level (600< altitudes <750 m); and higher level (altitudes ≥750 m). We registered nine fragments, three per altitude level. In each of them, we distributed 20 rectangular sampling units with 250 m², totaling a sampling area of 4.5 ha. We quantified, collected, and identified woody plants with a diameter at breast height higher than or equal to 0.1 m (DBH 1.30 m ≥0.10 m). We characterized the dispersal syndrome according to the characteristics of the fruits and seeds and based on a literature review. In the whole region, we sampled 6,987 individuals, distributed in 35 families, 82 genera, and 153 species. Approximately 41% of all individuals are dispersed by animals, 37% by the plant’s own mechanisms, and 21% by the wind. In terms of dispersal, 47% of species were classified as zoochorous, 23% as autochorous, and 14% as anemochorous. Seed dispersal patterns vary according to altitude levels, with higher regions tending to present greater representativeness of biotic dispersers and lower ones, abiotic

    ANTIFUNGAL POTENTIAL OF BARK EXTRACTS FROM BRAZILIAN SEMI-ARID TREE SPECIES AGAINST Ganoderma spp.

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    Tree native species of the Caatinga (a Brazilian semi-arid biome) have characteristics of interest for the use of their wood and non-wood products, especially regarding their natural chemical compounds. The aim of this study was to evaluate the antifungal action of different bark extracts of Anacardium occidentale, Ziziphus joazeiro and Mimosa caesalpiniifolia against Ganoderma lobatum and G. multiplicatum by in vitro mycelial inhibition. The extractions from the bark of the trees were carried out with a Soxhlet extractor, using water, ethanol and hexane as solvents. The potential of mycelia inhibition of each extract was tested against fungi of the Ganoderma genus. The hexane extracts of the bark had activity against G. multiplicatum, unlike the aqueous and ethanol extracts. Even though the hexane-based extracts had a small mycelial inhibition effect against G. lobatum, there were no satisfactory results of extracts against this fungus species

    Wood-cement boards of Eucalyptus saligna with different chemical additives and methods of formation.

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    The aim of this work was evaluate the potential use of different chemical additives and methods of formation for wood-cement composites with Eucalyptus saligna clones. Portland cement type II-Z was used as mineral bonding and Calcium chloride (CaCl2) and Magnesium chloride (MgCl2) as accelerator of the cement hydration. The wood-cement panels were produced by the cold press method with dimensions of 50.5 x 38.5 x1.5 cm, and by vibro-compaction densification with 35 x 7 x 1.5 cm. Both methods used a nominal density of 1.0 g/cm3 and wood: cement ratio of 1:2.75. Main results: (I) Hydration tests showed that E. saligna wood is compatible with Portland cement type II; (II) Use of Calcium and magnesium chlorides at 3% in relation of the cement dry weight improve physical and mechanical properties of wood-cement composites produced by studied methods; (III) Composites produced by vibro-compaction densification presented lower density, higher dimensional stability and higher internal bond than composites produced by the traditional cold press method.Keywords: Cement-wood composites; vibro-compaction; chemical accelerators.Este trabalho teve como objetivo avaliar o potencial de uso de diferentes aditivos químicos e métodos de formação na produção de compósitos cimento-madeira com clone de Eucalyptus saligna. Utilizou-se o cimento Portland tipo CP II-Z, como aglutinante mineral, e cloreto de cálcio (CaCl2) e cloreto de magnésio (MgCl2),como aceleradores de cura do cimento. Os painéis cimento-madeira foram produzidos pelo método de prensagem na prensa de pratos de 50,5 x 38,5 x1,5 cm, e pelo método de adensamento por vibrocompactação em dimensões de 35 x 7 x1,5 cm. Os painéis foram formados com densidade nominal de 1 g/cm³ e relação cimento:madeira de 2,75:1. Com base nos resultados, pode-se concluir que: (I) os testes de hidratação mostraram que a madeira é compatível com o cimento Portland tipo II; (II) o uso de cloreto de cálcio e de magnésio na proporção de 3% em relação à massa do cimento proporcionou incremento nas propriedades físicas e mecânicas dos painéis produzidos pelos dois métodos de formação avaliados; (III) os painéis produzidos pelo método de adensamento por vibrocompactação apresentaram menor densidade média, maior estabilidade dimensional e melhor tração perpendicular do que os painéis produzidos pelo método tradicional de prensa de pratos.Palavras-chave: Compósito cimento-madeira; vibro compactação; aceleradores de cura. AbstractWood-cement boards of Eucalyptus saligna with different chemical additives and methods of formation. The aim of this work was evaluate the potential use of different chemical additives and methods of formation for wood-cement composites with Eucalyptus saligna clones. Portland cement type II-Z was used as mineral bonding and Calcium chloride (CaCl2) and Magnesium chloride (MgCl2) as accelerator of the cement hydration. The wood-cement panels were produced by the cold press method with dimensions of 50.5 x 38.5 x1.5 cm, and by vibro-compaction densification with 35 x 7 x 1.5 cm. Both methods used a nominal density of 1.0 g/cm3 and wood: cement ratio of 1:2.75. Main results: (I) Hydration tests showed that E. saligna wood is compatible with Portland cement type II; (II) Use of Calcium and magnesium chlorides at 3% in relation of the cement dry weight improve physical and mechanical properties of wood-cement composites produced by studied methods; (III) Composites produced by vibro-compaction densification presented lower density, higher dimensional stability and higher internal bond than composites produced by the traditional cold press method.Keywords: Cement-wood composites; vibro-compaction; chemical accelerators

    Physical and mechanical properties of wood of Toona ciliata at different ages

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    O presente trabalho teve como objetivo caracterizar a madeira de árvores de Toona ciliata (cedro australiano) aos 6, 12 e 18 anos de idade, provenientes de um plantio florestal na região de Venda Nova do Imigrante, ES. Foram avaliadas as propriedades físicas quanto à densidade básica e à retratibilidade e as propriedades mecânicas quanto à resistência à compressão axial e ao módulo de ruptura e módulo de elasticidade à flexão estática da madeira. Foram utilizadas três árvores para cada idade, das quais foram retiradas toras, que foram desdobradas em pranchas radiais para retirada de corpos de prova, ensaiados de acordo com as normas MB 26/40 (ABNT, 1940) e NBR 7190 (1997). Observou-se o aumento da densidade básica e a redução das contrações tangencial e volumétrica e do fator anisotrópico em função do aumento da idade. O uso da madeira deve ser limitado em situações que exijam elevada resistência mecânica e na fabricação de produtos com elevada estabilidade dimensional. Deve-se optar por árvores com idades superiores, viabilizando a aplicabilidade da madeira com qualidade para diversos fins.Palavras-chave: Cedro australiano; resistência da madeira; estabilidade dimensional. AbstractPhysical and mechanical properties of wood of Toona ciliata at different ages. The objective of the present study was to characterize the wood of trees Toona ciliata at 6, 12 and 18 years old, coming from forest plantations in the region of Venda Nova do Imigrante at Espírito Santo State in Brazil. We evaluated the physical properties as the specific gravity and shrinkage, and the mechanical parameters in relation to the compressive strength and modulus of rupture and elasticity in static bending. We use tree logs that were sawed and prepared the samples for analysis according to standards MB 26/40 (ABNT, 1940) e NBR 7190 (1997). We observed an increase in specific gravity and decrease of tangential and volumetric shrinkages and the anisotropic factor with the increase for the age. The use of this wood should be limited in situations which high mechanical strength is required and manufacture of products with high dimensional stability. We should opt for more aged trees, allowing the applicability of quality wood for various purposes.Keywords: Australian cedar; wood resistance; dimensional stability.AbstractThe objective of the present study was to characterize the wood of trees Toona ciliata at 6, 12 and 18 years old, coming from forest plantations in the region of Venda Nova do Imigrante at Espírito Santo State in Brazil. We evaluated the physical properties as the specific gravity and shrinkage, and the mechanical parameters in relation to the compressive strength and modulus of rupture and elasticity in static bending. We use tree logs that were sawed and prepared the samples for analysis according to standards MB 26/40 (ABNT, 1940) e NBR 7190 (1997). We observed an increase in specific gravity and decrease of tangential and volumetric shrinkages and the anisotropic factor with the increase for the age. The use of this wood should be limited in situations which high mechanical strength is required and manufacture of products with high dimensional stability. We should opt for more aged trees, allowing the applicability of quality wood for various purposes.Keywords: Australian cedar; wood resistance; dimensional stability

    CONDIÇÕES DE TRABALHO EM UMA MADEIREIRA EM BELO JARDIM, PERNAMBUCO

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    O setor madeireiro, apesar de possuir destaque dentro do cenário industrial brasileiro, caracteriza-se como um setor com grande potencial de ocorrência de acidentes e desencadeamento de doenças ocupacionais, mostrando que este não gera impacto somente na natureza, mas na qualidade de vida. O objetivo desse trabalho foi identificar as condições de trabalho em uma indústria de beneficiamento de madeira em Belo Jardim, Pernambuco, sob o ponto de vista da salubridade e da segurança, a fim de propor melhorias e adequações a serem realizadas de acordo com a legislação trabalhista vigente. A partir das metodologias das Normas de Higiene Ocupacional, verificou-se a necessidade de mudanças pontuais no layout da empresa, além da necessidade de trocar o protetor auricular e desenvolver um projeto para otimizar a iluminação da fábrica de maneira geral. Para atendimento à legislação trabalhista, existe a necessidade de elaboração de laudo técnico de condições ambientais do trabalho, formação de comissão interna de prevenção de acidentes e desenvolvimento de um programa de controle médico e saúde ocupacional, incentivando a prática de realização de exames periódicos nos funcionários.Palavras-chave: salubridade; ergonomia; segurança do trabalho; legislação trabalhista. WORKING CONDITIONS IN A WOOD INDUSTRY IN BELO JARDIM, PERNAMBUCO ABSTRACT: The timber industry in general has a great prominence within the Brazilian industrial scenario, is still a sector with great potential for accidents and triggering of occupational diseases, showing that this does not only impact on nature, but on the quality of life This study aimed to identify the working conditions in a wood processing industry in Belo Jardim, Pernambuco, from the point of view of health and safety, in order to adapt them according to the current labor legislation. Based on the methodologies of Occupational Hygiene Standards, it was verified the need for specific changes in the company layout, change the hearing protector and develop a project to optimize the lighting of the factory. In order to comply with labor legislation, there is a need for the preparation of a technical report on environmental conditions of work, formation of an internal accident prevention committee, and development of a medical control and occupational health program, encouraging the practice of periodic exams for employees.Keywords: health; ergonomics; workplace safety; labor legislation

    Vegetação lenhosa de regiões semiáridas em diferentes altitudes

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    This work aimed to evaluate the floristic diversity at different altitudes in the Araripe region of Pernambuco state, Brazil. For method purposes, the region was stratified into three levels of altitude: inferior (until 600 m), intermediate (&gt;600 and &lt;750) and superior (≥750 m). Nine forest fragments were inventoried, three by altitudinal stratum. Twenty rectangular sampling units of 250 m² each were distributed for each fragment, totaling a sampling area of 4.5 ha. All woody individual’s quantification, collection, and identification were performed with respect to the Circumference at Breast Height (CBH) greater than or equal to 0.10 m (CBH at 1.30m ≥ 0.10m). The richness and the floristic similarity among the fragments and altitude levels were analyzed. A total of 6,987 individuals were sampled and distributed in 35 botanical families, 82 genera and 153 species. The region presented great floristic richness, with variation among and within the three altitudinal levels and the diversity demonstrated to increase with the altitude. Most species exhibited little phenotypic plasticity, with occurrence and abundance restricted to the fragment or the altitude level. At short geographical distances, relevant phyto-physiognomic variations were diagnosed, which corroborates with the importance of altitude stratification and fragment replication in the sampling procedures. Due to the level of anthropogenic degradation and the intensification of forest activities in the region, it is, therefore, necessary and urgent to create public policies aiming sustainable practices in forest use and its conservation process. To this end, the negligence of this problem puts at risk of extinction a large representation of the Brazilian northeastern vegetation diversity.O objetivo deste trabalho foi avaliar diversidade florística em diferentes altitudes na região do Araripe em Pernambuco, Brasil. Metodologicamente, a região foi estratificada em três níveis de altitude: inferior (até 600 m), intermediário (maior que 600 e menor que 750 m) e superior (igual ou maior que 750 m). Foram inventariados nove fragmentos florestais, três por estrato altitudinal. Em cada fragmento, distribuíramse 20 unidades amostrais retangulares, de 250 m² cada, totalizando área amostral de 4,5 ha. Nas áreas amostrais foram quantificados, coletados e identificados todos os indivíduos lenhosos com nível de inclusão de circunferências a altura do peito (CAP) maior ou igual a 0,10 m (CAP a 1,30 m ≥ 0,10 m). Analisou-se, riqueza e similaridade florística entre fragmentos e níveis de altitudes. Foram amostrados 6.987 indivíduos, distribuídos em 35 famílias botânica, 82 gêneros e 153 espécies. A região apresenta grande riqueza florística, com variação entre e dentro dos três níveis altitudinais, com tendência de aumento na diversidade com a elevação da altitude. A maioria das espécies apresentaram pouca plasticidade fenotípica, com ocorrência e abundância restrita ao fragmento ou altitude. Em pequenas distâncias geográficas foram diagnosticadas relevantes variações fitofisionômicas, o que corrobora a importância da estratificação de altitudes e replicação de fragmentos na amostragem. Pelo nível de degradação antropogênica e a intensificação das atividades florestais da região, faz-se necessário e urgente a criação de políticas públicas voltadas para práticas sustentáveis no uso da floresta e seu processo de conservação. Para tanto, o negligenciamento a esta problemática, coloca em risco de extinção uma grande representação da diversidade vegetacional do nordeste brasileiro

    Production of plywood using veneers of Sequoia sempervirens and urea-formaldehyde resin

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    ResumoEsta pesquisa teve por objetivo avaliar a qualidade dos painéis compensados multilaminados produzidos com lâminas de madeira de Sequoia sempervirens (D. Don) Endl. Foram produzidos em laboratório compensados com cinco lâminas de 2,0 mm de espessura, colados com resina ureia-formaldeído (UF), com duas diferentes formulações de batida de cola e gramaturas. Os painéis foram prensados com pressão específica de 10 kgf/cm², temperatura de 110 ºC e tempo de prensagem de 10 minutos. Foram avaliadas as propriedades de resistência da linha de cola aos esforços de cisalhamento (RLC) e flexão estática paralelo e perpendicular (MOE e MOR). De uma forma geral, as diferentes formulações da batida de cola e gramaturas não afetaram significativamente os resultados das propriedades dos painéis, o que representa um aspecto importante sob o ponto de vista econômico. Os valores médios de RLC e percentagem de falhas na madeira atendem aos requisitos mínimos da norma EN 314-2 (1993). Os resultados obtidos nesta pesquisa indicam a possibilidade de uso de lâminas de sequoia para o miolo de painéis compensados para uso interior e de forma associada com lâminas de espécies com maior resistência mecânica nas capas.AbstractProduction of plywood using veneers of Sequoia sempervirens and urea-formaldehyde resin. This research was carried out to evaluate the quality of plywood made from wood veneer of Sequoia sempervirens. It was produced in laboratory plywood composed by five veneers with 2.0 mm thick, bonded with urea-formaldehyde resin (UF) with two different formulations of glue and amount of glue spread. The panels were pressed with specific pressure of 10 kgf/cm², temperature of 110 °C and pressing time of 10 minutes. It was evaluated the properties of the glue line shear strength (RLC) and static bending (MOE and MOR) parallel and perpendicular. In general, the different adhesive formulations and amount of spread glue did not significantly affect the results of the properties of the panels, which represent an important aspect on the economic point of view. The mean values of RLC and percentage of wood failure meet minimum requirements of standard EN 314-2 (1993). The results of this research revealed the possibility to using the veneers of sequóia for the core of internal use plywood associated with greater strength species on the faces.Keywords: Wood veneer; sequoia; plywood; urea-formaldehyde.This research was carried out to evaluate the quality of plywood made from wood veneer of Sequoia sempervirens. It was produced in laboratory plywood composed by five veneers with 2.0 mm thick, bonded with urea-formaldehyde resin (UF) with two different formulations of glue and amount of glue spread. The panels were pressed with specific pressure of 10 kgf/cm², temperature of 110 °C and pressing time of 10 minutes. It was evaluated the properties of the glue line shear strength (RLC) and static bending (MOE and MOR) parallel and perpendicular. In general, the different adhesive formulations and amount of spread glue did not significantly affect the results of the properties of the panels, which represent an important aspect on the economic point of view. The mean values of RLC and percentage of wood failure meet minimum requirements of standard EN 314-2 (1993). The results of this research revealed the possibility to using the veneers of sequóia for the core of internal use plywood associated with greater strength species on the faces
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