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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.
91

Technological Investigation of Prosopis leavigata Wood from Northeast Mexico / Technologische Untersuchung an Prosopis laevigata - Holz aus Nordosten Mexikos / Technological Investigation of Prosopis leavigata Wood from Northeast Mexico

Carrillo-Parra, Artemio 14 September 2007 (has links)
No description available.
92

Fungal Pigment Formation in Wood Substrate

Tudor, Daniela 14 January 2014 (has links)
A number of fungi produce spalted wood, which is characterized by accumulation of black pigment in fine demarcation lines, often accompanied by discoloration or staining on the wood fibers. Specific spalting fungi were identified by molecular analysis. From a total of 19 isolates and 140 clones studied, 11 fungal species were identified. The two Chlorociboria species from North America were investigated and their anamorphs were unambiguously identified for the first time. Fungal pigment formation under the influence of moisture content and pH variation was investigated in sugar maple, American beech and agar inoculated with spalting fungi. Maximum pigment production occurred at treatment with pH 4.5 for sugar maple and beech inoculated with Trametes versicolor. Xylaria polymorpha produced external pigmentation in beech treated with buffer at pH 5 and sugar maple at pH 4.5. Fungal pigmentation by Trametes versicolor and Xylaria polymorpha was stimulated at low moisture content in both wood species tested. Melanin production by Inonotus hispidus and Polyporus squamosus was stimulated above 22-28% and 34-38% moisture content in beech and in sugar maple respectively. Fomes fomentarius and Polyporus brumalis produced maximum pigmentation in beech at 26 - 41% and in sugar maple at 59 - 96% moisture content. The variation of the moisture content and pH values of wood substrates can stimulate the intensity of pigmentation of specific fungi in wood. To investigate melanin synthesis from a variety of melanin precursors, experimental research on three spalting fungi tested their reaction to catechol and L-Dopa melanin precursors in wood and agar substrate. The results indicate multiple biosynthesis pathways for melanin assembly in Trametes versicolor, Xylaria polymorha and Inonotus hispidus, and catechol produced most pigmentation in all spalting fungi investigated. Microscopic analysis by light, fluorescence, electron and confocal microscopy also indicates a bi- or multi-modal activity of melanin production and assembly by several spalting fungi. Possible variations of melanin assembly were identified based on fungal and wood species. Immunofluorescence and immunogold labelling with Mab 6D2 melanin antibody confirmed the melanin nature of the pigments produced by Oxyporus populinus, Trametes versicolor, Xylaria polymorpha, Fomes fomentarius, and Inonotus hispidus.
93

Fungal Pigment Formation in Wood Substrate

Tudor, Daniela 14 January 2014 (has links)
A number of fungi produce spalted wood, which is characterized by accumulation of black pigment in fine demarcation lines, often accompanied by discoloration or staining on the wood fibers. Specific spalting fungi were identified by molecular analysis. From a total of 19 isolates and 140 clones studied, 11 fungal species were identified. The two Chlorociboria species from North America were investigated and their anamorphs were unambiguously identified for the first time. Fungal pigment formation under the influence of moisture content and pH variation was investigated in sugar maple, American beech and agar inoculated with spalting fungi. Maximum pigment production occurred at treatment with pH 4.5 for sugar maple and beech inoculated with Trametes versicolor. Xylaria polymorpha produced external pigmentation in beech treated with buffer at pH 5 and sugar maple at pH 4.5. Fungal pigmentation by Trametes versicolor and Xylaria polymorpha was stimulated at low moisture content in both wood species tested. Melanin production by Inonotus hispidus and Polyporus squamosus was stimulated above 22-28% and 34-38% moisture content in beech and in sugar maple respectively. Fomes fomentarius and Polyporus brumalis produced maximum pigmentation in beech at 26 - 41% and in sugar maple at 59 - 96% moisture content. The variation of the moisture content and pH values of wood substrates can stimulate the intensity of pigmentation of specific fungi in wood. To investigate melanin synthesis from a variety of melanin precursors, experimental research on three spalting fungi tested their reaction to catechol and L-Dopa melanin precursors in wood and agar substrate. The results indicate multiple biosynthesis pathways for melanin assembly in Trametes versicolor, Xylaria polymorha and Inonotus hispidus, and catechol produced most pigmentation in all spalting fungi investigated. Microscopic analysis by light, fluorescence, electron and confocal microscopy also indicates a bi- or multi-modal activity of melanin production and assembly by several spalting fungi. Possible variations of melanin assembly were identified based on fungal and wood species. Immunofluorescence and immunogold labelling with Mab 6D2 melanin antibody confirmed the melanin nature of the pigments produced by Oxyporus populinus, Trametes versicolor, Xylaria polymorpha, Fomes fomentarius, and Inonotus hispidus.
94

Estudo da qualidade de madeiras de árvores caídas em área de manejo florestal para o desenvolvimento de produtos

Silva, Mirella Sousa e 10 December 2013 (has links)
Made available in DSpace on 2015-04-13T12:17:18Z (GMT). No. of bitstreams: 1 Mirella Sousa e Silva.pdf: 4348220 bytes, checksum: 2d704f24c4db705f03cb6de47906f926 (MD5) Previous issue date: 2013-12-10 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / This paper presents a study of technological characteristics and of use for the development of products from some species from naturally fallen trees in the Amazon. The research is bounded by the analysis of their physical properties and application of the proposal based on the study of the wood quality. Taking as reference to the experiments the determination of the basic density and dimensional stability of the species, as also procedures related to their processing. In addition to the fundamental principles adopted by forest management in this context, the paper also reports the participation of design as a strategic tool for the conception of products, of which its main attributes such as shape, function and ergonomics has been used. From the results achieved , the research highlights that many of the physical properties of the studied species has showed good indication for the manufacture of products, although this wood is not used commercially by unfamiliarity of its potential. In conclusion, we observed that the use of wood of fallen tree in the design of products is a viable alternative and may represent an excellent opportunity of economic return. Coupled with the knowledge of wood technology and design methodology for the development of good projects, which can also help reduce the pressure around the living forest. / Este trabalho apresenta um estudo das características tecnológicas e de uso para o desenvolvimento de produtos a partir de algumas espécies oriundas de árvores naturalmente caídas da Amazônia. A pesquisa é delimitada pela análise de suas propriedades físicas e aplicação da proposta com base no estudo da qualidade da madeira. Tendo como referencia para a realização dos experimentos a determinação da densidade básica e estabilidade dimensional das espécies; como também procedimentos relacionados ao seu processamento. Além dos princípios fundamentais adotados pelo manejo florestal para este contexto, o documento também relata a participação do design como um instrumento estratégico para a concepção de produtos, dos quais se utilizou os seus principais atributos como forma, função e ergonomia. Dos resultados alcançados, a pesquisa ressalta que as propriedades físicas de muitas das espécies estudadas apresentaram boa indicação para a confecção de produtos, ainda que esta madeira não seja utilizada comercialmente pelo desconhecimento deste potencial. Como conclusão, observou-se que o uso da madeira caída para o design de produtos é uma alternativa viável e pode representar uma excelente oportunidade de retorno econômico. Aliado ao conhecimento da tecnologia da madeira e a metodologia de design para o desenvolvimento de bons projetos, o que também pode contribuir para minimizar as pressões exercidas em torno da floresta viva.
95

Agrupamento das espécies madeireiras ocorrentes em pequenas áreas sob manejo florestal do projeto de colonização Pedro Peixoto (AC) por similaridade das propriedades físicas e mecânicas. / Grouping of the wood species occurring in small farms under forest management on the Pedro Peixoto colonization project (AC), by similarity of the physical and mechanical properties.

Henrique José Borges de Araújo 04 September 2002 (has links)
O manejo florestal sustentado mostra-se uma solução tecnológica adequada para a região amazônica. A exploração seletiva das espécies madeireiras tradicionais vem ocasionando a escassez dessas espécies. É necessário melhorar o aproveitamento dos recursos florestais amazônicos, aproveitando o máximo de suas potencialidades. As espécies de madeira exploradas para fins comerciais são poucas, sendo que há muitas outras com potencial de uso. Vários fatores mostram que o estado do Acre tem aptidão para atividades florestais. O objetivo do presente trabalho é agrupar, por similaridade das propriedades físicas e mecânicas, as madeiras ocorrentes em áreas sob manejo florestal, identificando espécies com potencial de uso e comercialização. A revisão bibliográfica abordou aspectos relacionados ao mercado internacional de madeiras, ao consumo da produção madeireira amazônica, ao uso sustentado dos recursos florestais, a novas espécies de madeira, à caracterização geral do material Madeira, e, à análise estatística multivariada. A área do estudo é composta por 12 pequenas propriedades localizadas no estado do Acre. A área total sob manejo florestal das propriedades é de 431 ha. O plano de manejo florestal prevê a exploração de 8,0 m 3 .ha -1 de madeira em um compartimento de 3,6 ha ao ano em cada propriedade. As espécies do estudo foram as ocorrentes no inventário florestal a 100% em 206,8 ha das propriedades. Os parâmetros dendrométricos (totais e por hectare) foram: número de árvores (N), volume (V), área basal (ABs) e Índice de Importância da Espécie (IND). Neste estudo foram utilizadas três propriedades físicas e nove mecânicas, e os dados foram obtidos por meio de consultas bibliográficas. Às propriedades físicas e mecânicas das madeiras foram realizadas análises de correlações e ajustadas equações de regressão para estimativas a partir da densidade básica (DEb). Foram três os agrupamentos das espécies: o primeiro com base em DEb; o segundo com base em todas as propriedades; e, o terceiro com base apenas nas principais propriedades para diferentes usos finais. O segundo e o terceiro agrupamento foram por meio da análise multivariada. Os cálculos estatísticos foram no programa SAS. O segundo agrupamento foi analisado em termos de importância estatística das propriedades, composição e uso final das madeiras e importância pelo parâmetro IND (Índice de Importância da Espécie). Os resultados do inventário foram: N total de 3.871; AB (abundância) de 18,7 árvores.ha -1 ; V total de 22.244,44 m 3 ; V hectare de 107,56 m 3 ; ABs total de 1.461,96 m 2 ; e, ABs hectare de 7,07 m 2. Foram reconhecidas na área do estudo 204 espécies, pertencentes a 136 gêneros e a 43 famílias. O total das espécies para os agrupame ntos foi 187, sendo que 113 (60,4%) foram localizadas na literatura por coincidência de gênero e 74 (39,6%) foram localizadas ao nível de espécie. Houve expressiva correlação entre as propriedades, sendo que os maiores CCORR médios foram CPpar, DUtr e DEb. As equações de regressão apresentaram coeficientes de determinação (R 2 ) satisfatórios, em geral, acima de 0,8. O agrupamento com base na DEb revelou que 84% das espécies são das classes Média, Leve e Pesada, e 16% são das classes Muito Leve e Muito Pesada. O segundo agrupamento revelou a formação de cinco grupos de espécies, sendo que a quantidade de cada grupo foi 33, 46, 19, 46 e 43. As propriedades de maior importância estatística para os agrupamentos foram DUtr, FEe, DUpa, DEb, TRper e CPpel. O IND dos grupos mostrou que todos possuem espécies com bom potencial para o manejo florestal. Os agrupamentos por meio da análise multivariada apresentaram resultados coerentes, e, portanto, válidos. Os resultados obtidos neste trabalho permitem admitir que a massa específica da madeira é o melhor indicativo para usos dependentes da resistência a esforços mecânicos. / The sustained forest management is accepted as an appropriate technological solution for the Amazon Region. The selective explotation of the traditional wood species is causing the shortage of those species. It is necessary to improve the use of the Amazon forest resources, taking the maximum advantage of their potentialities. The wood species explored for commercial uses are few, and there are many others with use potential. Several factors show that the state of Acre has the aptitude for forest activities. The objective of the present work is to group, by similarity of their physical and mechanical properties, the woods that occur in areas under forest management, identifying species with use and marketing potentiality. The bibliographical revision focused on aspects related to the international market of wood, the consumption of the wood produced in the Amazon, the sustained use of forest resources, new wood species, the general characterization of the Wood material and the statistical analysis. The study area is composed of 12 small farms located in the state of Acre. Their total area under forest management 431 hectares. The forest management plan estimates the extraction of 8.0 m 3 .ha -1 of wood from a compartment of 3.6 hectares per year in each property. The species of the study are the ones that occurred in the forest inventory to 100% in 206.8 hectares. The mensuration parameters selected (total and per hectare) were: number of trees (N), volume (V), basal area (ABs) and Index of Importance of the Specie (IND). In this study three physical properties and nine mechanical properties were used, the data being obtained from bibliographic consultations. Correlation analyses among the wood properties were carried out and the regression equations were adjusted for estimates starting from the basic density (DEb). Three were the groupings of species obtained: the first based on DEb; the second based on all other properties; and the third based on the main properties for different final uses. The second and third groupings were by multivariate analysis. The statistical calculations were done by the SAS program. The second grouping was analyzed in terms of statistical importance of the properties, by composition and final use of the wood, and importance by the parameter IND (Index of Importance of the Species). The results of the inventory were: N total 3,871; AB (abundance) 18.7 trees.hectare -1 ; V total 22,244.44 m 3 ; V hectare 107.56 m 3 ; ABs total 1,461.96 m 2 ; and, ABs hectare 7.07 m 2 . In the area of the study 204 species were recognized, belonging to 136 botanical genera and 43 familiae. The total species for grouping were 187; 113 (60.4%) were located in the literature by coincidence of genera and 74 (39.6%) species level. High correlation among properties was detected, with the highest average CCORR being CPpar, DUtr e DEb. The regression equations showed satisfactory determination coefficients (R 2 ), in general, above 0.8. The grouping based on DEb revealed that 84% of the species belong to the Middle, Light and Heavy weight classes, and 16% to the Very Light and Very Heavy classes. The second grouping revealed the formation of five groups of species, and the numbers in each group were 33, 46, 19, 46 e 43. The properties of larger statistical importance for the groupings were DUtr, FEe, DUpa, DEb, TRper e CPpel. The IND of the groups showed that all contain species with good potential for the forest management. The groupings by multivariate analysis presented coherent results, and, therefore, valid. The results obtained in this work allow to admit that the specific gravity of the wood is the best indicative for dependent uses of the resistance to mechanical efforts.
96

Características tecnológicas do vergamento das madeiras de Luehea divaricata, Carya illinoinensis e Platanus x acerifolia como subsídios para o manejo florestal. / Technological characteristics of bending of the wood ofLuehea divaricata, Carya illinoinensis and Platanus x acerifolia as subsidies for the forest handling.

Gatto, Darci Alberto 27 April 2006 (has links)
The present work was developed with the objective of investigating the characteristics of bending of the wood of Sycamore (Platanus x acerifolia), açoita-cavalo (Luehea divaricata), and pecan (Carya illinoinensis) coming from forests non managed for this end from the area of the Depressão Central and Encosta Superior do Nordeste of the state Rio Grande do Sul/Brasil. There were cut down five representative trees of each species and study area. There were determined the characteristics such as log as taper and idiosyncrasy. In the study there was defined the year of segregation of juvenile/adult wood by means of the radial variation of anatomical characteristics and basic density. The wood was bent in rays of 16 and 21 cm, with wood initial moisture of 14%, and after water boiling for 35 minutes. For the qualification of the defects of the bending wood, the methodology described by Vorreiter (1958) was followed. The most probable year of segregation is the defined by the radial variation of fiber length that was determined, respectively as, 21, 16 and 14 years for açoita-cavalo, pecan and sycamore. With relationship to the quality of the wood bending, the juvenile wood was surprisingly better than the adult wood for the rays and tested species. In this resard, there are not great needs of a forest handling that decreases the amount of juvenile wood. Nevertheless, trunk breakdown should be made respecting the direction of the fibers; thus, avoiding the main defect of the wood bending (splintering by tension). The best results of the bending wood were observed for the wood of pecan. Possibly, the ring porous wood, characteristic of the species, contributed in the result. Meanwhile, açoita-cavalo and sycamore, wood with diffuse porosity and of high parenchyma proportion, presented a great amount of defective pieces. / O presente trabalho foi desenvolvido com o objetivo de investigar as características do vergamento da madeira de plátano (Platanus x acerifolia), açoita-cavalo (Luehea divaricata) e nogueira-pecã (Carya illinoinensis) procedentes de florestas não-manejadas para este fim das regiões da Depressão Central e Encosta Superior do Nordeste do estado do Rio Grande do Sul/Brasil. Foram abatidas cinco árvores adultas representativas de cada espécie e Região de estudo, das quais foram determinadas as características da forma do tronco como conicidade e índice de circularidade. No estudo definiu-se o ano de segregação dos lenhos juvenil/adulto por meio da variação radial de características anatômicas e de massa específica básica. As madeiras das espécies testadas foram vergadas em raios de 16 e 21 cm, com teor de umidade inicial de aproximadamente 14%, após cozimento em água fervente por 35 minutos. Para a qualificação dos defeitos de vergamento, foi seguida metodologia descrita por Vorreiter (1958). Os principais resultados indicam que o ano de segregação mais provável é o definido pela variação radial do comprimento da fibra que foi, respectivamente, 21, 16 e 14 anos para açoita-cavalo, nogueira-pecã e plátano. Quanto à qualidade do vergamento, os corpos-deprova do lenho juvenil vergaram surpreendentemente melhor que os corpos-de-prova do lenho adulto para os raios e espécies testadas. Dessa forma, não há grandes necessidades de um manejo florestal que diminua a quantidade de lenho juvenil. No entanto, o desdobro das toras deve ser feito respeitando a direção das fibras, assim evitando o principal defeito do vergamento observado (estilhaço). Na madeira de nogueira-pecã, foram observados os melhores resultados do vergamento independentemente do raio. Aparentemente, a porosidade em anel, característica da espécie, contribuiu para o resultado. Já as madeiras de açoita-cavalo e plátano, com porosidade difusa e com grande proporção de parênquima, apresentaram uma grande quantidade de peças defeituosas.
97

Avaliação da qualidade da madeira das espécies Acacia crassicarpa, Acacia mangium, Eucalyptus nitens, Eucalyptus globulus e Populus tremuloides / Evaluation of the wood quality of species Acacia crassicarpa, Acacia mangium, Eucalyptus nitens, Eucalyptus globulus and Populus tremuloides

Antunes, Fernanda Schablatura 10 June 2009 (has links)
As madeiras utilizadas para produção de polpa celulósica podem ser divididas em dois grupos em função da fibra: folhosas (fibra curta) e coníferas (fibra longas), as espécies de folhosas são destinadas especialmente a papéis de escrita e impressão. As principais espécies de folhosas utilizadas para produção de polpa de fibra curta em outros países são o Eucalyptus globulus (Península Ibérica e Chile), Eucalyptus nitens (Chile), Populus tremuloides (Canadá), Acacia mangium, Acacia crassicarpa (Indonésia). Este projeto tem por objetivo: avaliar e comparar o desempenho de madeiras utilizadas mundialmente para produção de polpa celulósica de fibra curta considerando parâmetros de qualidade da madeira tais como composição química, densidade básica, características anatômicas da madeira; com objetivo de fornecer informações estratégicas para o setor nacional de celulose e papel, visando o conhecimento e posicionamento em competitividade destas madeiras no mercado mundial. Para a realização deste trabalho foram coletadas 5 árvores de cada espécie as quais foram utilizados cavacos cortados manualmente obtidos de discos; com relação à madeira foram determinadas densidade básica, composição química e dimensões de fibras. Os resultados foram analisados estatisticamente sendo comparadas as diferentes espécies referentes à qualidade da madeira. / Wood used for pulp production may be divided in two major groups regarding fiber function: hardwood (short fiber) and softwood (long fibers). Hardwood species are mainly designated to writing and printing papers. Hardwood principal species used for production of short fiber pulp in other countries are Eucalyptus globulus (Iberian Peninsula and Chile), Eucalyptus nitens (Chile), Populus tremuloides (Canada), Acacia mangium and Acacia crassicarpa (Indonesia). This study aimed to evaluate and compare the performance of the main woods used worldwide for short fiber pulp production regarding wood quality parameters such as chemical composition, basic density and wood anatomical properties, in order to provide strategic information for national pulp and paper industry, aiming the knowledge and competitiveness of these woods at worldwide market. To accomplish this study, 5 trees from each species were collected and wood chips were manually cut. In relation to the wood, basic density, chemical composition and fiber lengths were determined. The results were statistically analyzed and the different species were compared regarding wood quality.
98

Avaliação da qualidade da madeira das espécies Acacia crassicarpa, Acacia mangium, Eucalyptus nitens, Eucalyptus globulus e Populus tremuloides / Evaluation of the wood quality of species Acacia crassicarpa, Acacia mangium, Eucalyptus nitens, Eucalyptus globulus and Populus tremuloides

Fernanda Schablatura Antunes 10 June 2009 (has links)
As madeiras utilizadas para produção de polpa celulósica podem ser divididas em dois grupos em função da fibra: folhosas (fibra curta) e coníferas (fibra longas), as espécies de folhosas são destinadas especialmente a papéis de escrita e impressão. As principais espécies de folhosas utilizadas para produção de polpa de fibra curta em outros países são o Eucalyptus globulus (Península Ibérica e Chile), Eucalyptus nitens (Chile), Populus tremuloides (Canadá), Acacia mangium, Acacia crassicarpa (Indonésia). Este projeto tem por objetivo: avaliar e comparar o desempenho de madeiras utilizadas mundialmente para produção de polpa celulósica de fibra curta considerando parâmetros de qualidade da madeira tais como composição química, densidade básica, características anatômicas da madeira; com objetivo de fornecer informações estratégicas para o setor nacional de celulose e papel, visando o conhecimento e posicionamento em competitividade destas madeiras no mercado mundial. Para a realização deste trabalho foram coletadas 5 árvores de cada espécie as quais foram utilizados cavacos cortados manualmente obtidos de discos; com relação à madeira foram determinadas densidade básica, composição química e dimensões de fibras. Os resultados foram analisados estatisticamente sendo comparadas as diferentes espécies referentes à qualidade da madeira. / Wood used for pulp production may be divided in two major groups regarding fiber function: hardwood (short fiber) and softwood (long fibers). Hardwood species are mainly designated to writing and printing papers. Hardwood principal species used for production of short fiber pulp in other countries are Eucalyptus globulus (Iberian Peninsula and Chile), Eucalyptus nitens (Chile), Populus tremuloides (Canada), Acacia mangium and Acacia crassicarpa (Indonesia). This study aimed to evaluate and compare the performance of the main woods used worldwide for short fiber pulp production regarding wood quality parameters such as chemical composition, basic density and wood anatomical properties, in order to provide strategic information for national pulp and paper industry, aiming the knowledge and competitiveness of these woods at worldwide market. To accomplish this study, 5 trees from each species were collected and wood chips were manually cut. In relation to the wood, basic density, chemical composition and fiber lengths were determined. The results were statistically analyzed and the different species were compared regarding wood quality.
99

Les supports de peintures en bois dans les anciens Pays-Bas méridionaux de 1450 à 1650 : analyses dendrochronologiques et archéologiques / Wood painting supports in the southern part of the ancient Low Countries from 1450 to 1650 : dendrochronological and archaeological analyses

Fraiture, Pascale 05 July 2007 (has links)
Résumé L'examen archéologique et dendrochronologique des panneaux peints permet dappréhender les caractéristiques techniques relatives à la fabrication des supports de peinture. Puisque le corpus duvres couvre deux siècles de peinture dans les anciens Pays-Bas méridionaux, les analyses mettent en évidence les permanences ou les évolutions techniques de la mise en uvre du bois, et peuvent dès lors contribuer à une histoire matérielle de lart. Parallèlement, il est indispensable dintégrer la confection des supports dans un cadre plus large de production, en relation avec le contexte politique, économique et religieux de la région et de la période couvertes par notre étude. Le corpus duvres sur lequel repose cette thèse compte 143 peints datés entre 1450 et 1650. Quil sagisse de retables ou de panneaux de chevalet, tous ont été confectionnés et peints sur le territoire des Pays-Bas méridionaux, principalement dans des centres tels que Bruges, Bruxelles ou Louvain, aux XVe et XVIe siècles, ainsi quAnvers, aux XVIe et XVIIe siècles. La majeure partie des tableaux est issue du marché libre qui se développe dès la fin du XVe siècle dans les différents centres urbains ; quelques peintures de commande sy ajoutent. À lépoque qui nous occupe, le marché des panneaux peints est en pleine expansion. Au XVIe siècle, la demande en peintures de chevalet explose : posséder des tableaux fait partie des préoccupations de la bourgeoisie, même modeste. Au long de la période envisagée, le statut du panneau peint est ainsi passé de produit dexception (uvres de commande) à celui de produit usuel (panneaux de chevalet disponibles en grandes quantités sur le marché libre). Au XVIIe siècle, Anvers devient le fournisseur en peintures pour toutes les grandes villes dEurope. Au-delà dune meilleure compréhension ponctuelle de la chaîne opératoire de la fabrication des supports de peinture, des investigations dordre plus général ont été menées, pour replacer la réalisation du panneau destiné à être peint dans un contexte de production en pleine mutation. Laccroissement de la production de peintures sur bois dans les Pays-Bas méridionaux principalement au nord du pays soulève la question de lapprovisionnement en chêne, essence exclusive pour la confection des supports, dautant que la couverture forestière régionale est clairsemée et compte peu dindividus aux qualités requises pour la production de planches de panneaux. Ce constat conduit à sinterroger sur les sources qui ont permis de répondre à la demande en planches par les villes flamandes et brabançonnes. Dans ce contexte, il convenait également de prendre en considération les conséquences éventuelles sur lapprovisionnement en bois allochtone des bouleversements politiques et religieux qui secouèrent lEurope entière, à partir du troisième tiers du XVIe siècle et jusquaux traités de Westphalie au milieu du XVIIe siècle. Comme la période couverte par notre recherche (de la fin du moyen âge au début de lépoque moderne) est marquée par dimportantes évolutions techniques, il était intéressant de mesurer limpact que ces progrès ont pu avoir dans le domaine de la production des panneaux peints, et en particulier sur le débitage des planches nécessaires à leur confection. Dès lors, il était utile de sinterroger sur les conséquences de la scission survenue entre les Pays-Bas du Nord, grands spécialistes du sciage des planches, et ceux du Sud, qui dépendaient en grande partie de leurs voisins hollandais pour leur approvisionnement. Le développement considérable de la demande en peintures de chevalet a nécessairement conduit à une augmentation tout aussi importante de la demande en supports prêts à être peints. Des documents darchives attestent dailleurs que les artisans du bois ne parvenaient plus à honorer les innombrables demandes. Il était donc justifié de sinterroger sur les moyens quils ont mis en uvre pour améliorer leur productivité et leur rentabilité. À côté de ces constatations dordre contextuel, et plus concrètement, le matériel détude a nécessité le développement dune méthodologie propre à lexamen dendrochronologique des panneaux peints. Les résultats enregistrés et discutés tout au long de ce travail ont permis déclairer les apports et les limites de lapplication de cette discipline à des objets tels que les supports de peinture. Ils ont également mené à la constitution dun nouveau référentiel dendrochronologique adapté à la datation de peintures sur bois des anciens Pays-Bas. Abstract Archaeological and dendrochronological analyses of panel paintings yield results with respect to the technical characteristics related to the fabrication of the painting supports. Since the corpus of works studied covered two centuries of painting in the southern part of the ancient Low Countries, such analyses demonstrate persistence or technical development in woodworking, and thus contribute to the material history of art. Similarly, it is indispensable to integrate the production of supports within the broader framework of production, in relation to the political, economic and religious context of the region during the period covered by this study. The corpus of works on which this thesis is based comprises 143 panel paintings dated between 1450 and 1650. Whether altarpieces or easel paintings, all were created and painted in the southern Low Countries, principally in centres such as Bruges, Brussels and Leuven, during the 15th and 16th centuries, as well as in Antwerp, during the 16th and 17th centuries. The majority of the paintings are the result of the open market which developed at the end of the 15th century in different urban centres; several paintings made on order have also been studied. During the period of interest, the market for panel painting was in full expansion. In the 16th century, the demand for easel painting exploded: to own paintings was one of the interests of the bourgeoisie, even if modest. During this period, the status of the panel painting thus changed from being a rare commodity (works by order) to widespread (easel paintings available in large quantities on the open market). In the 17th century, Antwerp became the source of paintings for all of the large cities in Europe. Beyond a better, but episodic, understanding of the production sequence to prepare painting supports, investigation at a broader scale has also been carried out in order to place the production of panels destined to be painted within the context of production in full transformation. The rise in the production of paintings on wood in the southern Low Countries mainly in the northern part of the country raises the questions of procurement of oak, the exclusive material for supports, since the regional forest cover was sparse and had few trees with the qualities required for the production of panel planks. This observation led to investigation of the sources of wood responding to the demand for planks by Flemish and Brabant towns. In this context, it was also appropriate to consider the possible consequences of political and religious upheavals on non-local wood procurement from the last third of the 16th century to the Westphalia treaties in the middle of the 17th century. As the period examined in this research (end of the Middle Ages to the beginning of the Modern Era) is marked by significant technological developments, the impact of this progress in the area of panel painting production, and in particular on the cutting techniques of planks needed for their supports, was addressed. As a result, it was useful to examine the consequence of the scission between the northern Low Countries, specialists in sawing planks, and the southern part, which depended in large part on their Dutch neighbours for procurement. The considerable development in the demand for easel paintings necessarily led to an equally important increase in the demand for supports ready to be painted. Archival documents also show that wood artisans were no longer able to meet the innumerable requests. It was thus relevant to investigate the means they employed to improve their productivity and profitability. Next to these contextual observations, and more concretely, the material studied required the development of a methodology specific to the dendrochronological analysis of panel paintings. The results recorded and discussed throughout this thesis allow clarification of the contribution and limits of the application of this discipline to objects such as painting supports. They have also led to the construction of a new dendrochronological frame of reference adapted to the dating of paintings on wood in the ancient Low Countries.
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Anatomia ecol?gica e potencial econ?mico da madeira de esp?cies nativas da Mata Atl?ntica, Serra da Jiboia, Bahia, Brasil

Silva, Marcelo dos Santos 25 March 2013 (has links)
Submitted by Natalie Mendes (nataliermendes@gmail.com) on 2015-11-18T00:32:31Z No. of bitstreams: 1 Disserta??o - Marcelo dos Santos Silva - 2013.pdf: 7962051 bytes, checksum: 4e7968dec1d69dfb701ea5b5c43215dd (MD5) / Made available in DSpace on 2015-11-18T00:32:31Z (GMT). No. of bitstreams: 1 Disserta??o - Marcelo dos Santos Silva - 2013.pdf: 7962051 bytes, checksum: 4e7968dec1d69dfb701ea5b5c43215dd (MD5) Previous issue date: 2013-03-25 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / This study aimed to contribute to the knowledge of wood anatomy of the Atlantic Forest woody species, discussing their ecological/functional value, in addition to qualifying these species for energy generation and/or papermaking, based on derived values from measurements of the fibers and the bulk density. Serra da Jiboia is one of the areas indicated as priority for conservation of the Atlantic Forest and considered of extreme biological importance in terms of vegetation. Three to ten samples of 25 species were collected in the Serra da Jiboia, El?sio Medrado, Bahia. The portion from 1 to 3 cm from the bark was considered for making a macerate, histological slides, and measurement of the bulk density. The results are shown in two chapters and two appendices. In chapter 1, the existence of ecological trends for the Atlantic Forest of Serra da Jiboia was examined. The high frequency for growth rings boundaries distinct, diffuse porosity, absence of vessel arrangement, simultaneous presence of multiple and solitary vessels, simple perforation plates, tangential diameter of vessel larger than 350 ?m, nonseptate fibers, fiber length between 900-1600 ?m, fibers with simple to minutely bordered pits, rays per millimeter: 4-12, rays and/or axial elements irregularly storied and presence of inorganic inclusions. Most of these characteristics were interpreted as ecological trends for the Atlantic Forest of Serra da Jiboia, based on an analysis of the literature about their functional meanings and their correlation with the environmental characteristics of this environment. A smaller amount was assessed as arising from general evolutionary trends for the angiosperms. The conduction area, mesomorphy and vulnerability index, showed wide variation. More integrated studies involving wood anatomy which consider other aspects of the plants should be developed for a better understanding of the ecologic trends as well as its contrasting variations. In chapter 2, in which the anatomical and physical qualification of the wood for paper and/or energy production was made, four derived values ? wall fraction, flexibility coefficient, Runkel ratio and slenderness ratio ? and bulk density were measured. None of the species displayed all of the derived values optimal for paper production, although if each derived value is considered separately many of them could be qualified for this purpose. Most of the species were considered appropriate for power generation because they exhibit high wall fraction, Runkel ratio and high bulk density, and low flexibility coefficient. Aspidosperma discolor, Helicostylis tomentosa, Miconia amoena and Myrsine guianensis stand out from the rest. In conclusion, Serra da Jiboia proves to be a potential area for sustainable management studies of economically viable timbers. / Esse trabalho teve como objetivo contribuir para o conhecimento da anatomia do lenho de esp?cies arb?reas da Mata Atl?ntica, discutindo seu valor ecol?gico/funcional, al?m de qualificar estas esp?cies para gera??o de energia e/ou fabrica??o de papel, baseando-se nos valores derivados das dimens?es das fibras e na densidade aparente. A Serra da Jiboia ? uma das ?reas indicadas como priorit?rias para conserva??o da Mata Atl?ntica e classificada como de extrema import?ncia biol?gica no quesito vegeta??o. Foram coletadas de tr?s a dez amostras de 25 esp?cies nesta ?rea, localizada no munic?pio de El?sio Medrado, Bahia. Considerou-se a por??o entre 1-3 cm a partir da casca para confec??o de macerado, das l?minas histol?gicas e aferi??o da densidade aparente. Os resultados est?o apresentados em dois cap?tulos, e dois ap?ndices. No cap?tulo 1, examinou-se a exist?ncia de tend?ncias ecol?gicas para a Mata Atl?ntica da Serra da Jiboia, registrou-se alta frequ?ncia para an?is de crescimento distintos, porosidade difusa, aus?ncia de arranjo dos vasos, presen?a simult?nea de vasos solit?rios e m?ltiplos, placa de perfura??o simples, comprimento dos elementos de vasos maior que 350 ?m, fibras com ar?ola das pontoa??es simples a reduzida, presen?a de fibras n?o septadas, comprimento da fibra entre 900-1600 ?m, 4-12 raios por mil?metro, raios e elementos axiais n?o estratificados e presen?a de inclus?es inorg?nicas. A maioria destas caracter?sticas foi interpretada como tend?ncias ecol?gicas para a Mata Atl?ntica atrav?s da discuss?o com a literatura sobre seus significados funcionais e a correla??o destes com as caracter?sticas ambientais desse ambiente. Uma menor quantidade foi avaliada como decorrente das tend?ncias evolutivas gerais para as angiospermas. A ?rea de condu??o, ?ndice de vulnerabilidade e mesomorfismo apresentaram grande varia??o, trabalhos mais integrativos, envolvendo a anatomia da madeira, que considerem outros aspectos das plantas, devem ser desenvolvidos para uma melhor compreens?o das tend?ncias ecol?gicas, bem como da varia??o que se contrap?em a esta. No cap?tulo 2, no qual ? feita a qualifica??o anat?mica e f?sica da madeira para fabrica??o de papel e/ou produ??o de energia, quatro valores derivados ? fra??o parede, coeficiente de flexibilidade, ?ndice de Runkel e ?ndice de enfeltramento ? e a densidade aparente foram mensurados. Nenhuma esp?cie apresentou todos os valores derivados ?timos para a produ??o de papel, embora se considerado cada valor derivado isoladamente muitas delas podem ser qualificadas positivamente para este fim. A maioria das esp?cies apresentou-se aptas ? gera??o de energia por exibirem fra??o parede, ?ndice de Runkel e densidade aparente alta e baixo coeficiente de flexibilidade, destacando-se Aspidosperma discolor, Helicostylis tomentosa, Miconia amoena e Myrsine guianensis. Conclui-se, portanto, que a Serra da Jiboia apresenta-se como uma ?rea em potencial para estudos de manejo sustent?vel de madeiras economicamente vi?veis.

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