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The aims of this work were to determine the color change and physical–mechanical properties of polystyrene glulam from three tropical wood species. Wood laminas were cut from logs harvested from a young plantation forest of manii (Maesopsis eminii), mangium (Acacia mangium), and rubber-wood (Hevea brasiliensis). The laminas were impregnated with monomer styrene that was polymerized using potassium peroxy-disulfate as a catalyst and heat. Three-layer glulam was constructed from the polystyrene laminas, using isocyanate glue and cold press. For comparison purposes, three-layer untreated glulam and solid wood samples were prepared. The results showed that the color change of polystyrene glulam was very small compared with untreated glulam. Polystyrene glulam had the highest density, while the density of untreated glulam did not differ from that of the solid wood. The moisture content of all products was matched to the environment, and fulfilled the Japanese standard. Compared with both types of glulams, solid wood had lower values for modulus of rupture (MOR), modulus of elasticity (MOE), and hardness, but higher shear strength. Meanwhile, polystyrene glulam had lower values for MOR and MOE, equal shear strength and wood failure, and higher hardness than the untreated glulam. All glulams had very little delamination in the hot water test. Only rubber-wood glulams fulfilled JAS 234-2003 for MOR, MOE, shear strength, and delamination. To obtain adequate physical–mechanical properties of glulams, medium-density wood is recommended for glulam manufacturing.

A new approach in wood preservative treatment using carbon dioxide (CO 2 ) as a carrier solvent has been developed and evaluated its effect on the physical, mechanical, and biological properties of treated tropical wood. It employs CO 2 at various combinations of temperatures and pressures in a treatment vessel at once and is called Multi-Phase Carbon Dioxide (MPCO 2 ) treatment. Three commercial tropical wood species ( Agathis sp., Palaquium sp., and Heritiera sp.) measuring 1.5 cm (T) x 1.5 cm (R) x 15 cm (L) were prepared for the treatment with a termiticide (silafluofen). A treatment cycle was performed by loading two specimens of each wood species, applying the temperature of 15⁰C and pressure of 60 kg/cm 2 , gradually increasing the temperature and pressure, respectively, to 35⁰C and 80 kg/cm 2 , and releasing the pressure to atmosphere. The treatment was conducted with five replicates. Untreated and treated specimens were then evaluated their physical, mechanical, and biological properties. Results show that the MPCO 2 treatment significantly enhanced the termite resistance of treated wood without any adverse effects on their physical and mechanical properties. A new approach in wood preservative treatment using carbon dioxide (CO 2 ) as a carrier solvent has been developed and evaluated its effect on the physical, mechanical, and biological properties of treated tropical wood. It employs CO 2 at various combinations of temperatures and pressures in a treatment vessel at once and is called Multi-Phase Carbon Dioxide (MPCO 2 ) treatment. Three commercial tropical wood species ( Agathis sp., Palaquium sp., and Heritiera sp.) measuring 1.5 cm (T) x 1.5 cm (R) x 15 cm (L) were prepared for the treatment with a termiticide (silafluofen). A treatment cycle was performed by loading two specimens of each wood species, applying the temperature of 15⁰C and pressure of 60 kg/cm 2 , gradually increasing the temperature and pressure, respectively, to 35⁰C and 80 kg/cm 2 , and releasing the pressure to atmosphere. The treatment was conducted with five replicates. Untreated and treated specimens were then evaluated their physical, mechanical, and biological properties. Results show that the MPCO 2 treatment significantly enhanced the termite resistance of treated wood without any adverse effects on their physical and mechanical properties.

In this article I interrogate the complex relationship between nature and culture by examining how tropical nature and raw materials were conceptualized and displayed in the nineteenth century. I do so by discussing a display of tropical wood mounted by the Empire of Brazil for the Exposition Universelle in Paris in 1867. The reception of this display in Europe is analysed through Karl Max’s ideas on the gendering of nature and commodity exchange, through the concept of tropicality, and through Claude Levi-Strauss’s binaries of the raw and the cooked, which help reveal how natural materials were commodified into things themselves. Broadly, I am interested in putting ‘nature in our official past’ and bringing key concerns from environmental history studies to the fore, to bear on studies in design history.

This paper presents a modeling of an instrumental indirect solar wood dryer less expensive functioning in a Cameroonian climate applied to the climate of Yaounde. The dryer is easy to build and electric energy is only used for the fan. Applications are done on Iroko wood (Chlorophora excelsa), a tropical wood 50mm thick most utilized in Africa. A satisfactory agreement between experimental and numerical results was found. Influences of thickness, wood initial water content and airflow rate were studied.

O presente estudo teve como objetivo avaliar o comércio madeireiro no estado de Mato Grosso, analisando as principais espécies madeireiras comercializadas e os seus principais produtos gerados. Os dados foram coletados a partir dos relatórios de Beneficiamento e Comércio de Produtos da Madeira por Espécie Florestal e disponibilizados pela Secretaria de Estado do Meio Ambiente de Mato Grosso (SEMA-MT). O diagnóstico foi realizado no período entre 2007 e 2014, onde foram analisados o volume total, os valores comercializados das dez espécies mais comercializadas e dos seus produtos gerados. As dez espécies mais comercializadas (Erisma uncinatum Warm., Goupia glabra Aubl, Qualea albiflora Warm., Qualea paraensis Ducke, Mezilaurus itauba, Qualea sp., Hymenolobium sp., Apuleia sp., Trattinnickia sp. e Vochysia sp.) obtiveram um valor de 5,6 bilhões e um volume aproximado de 10,42 milhões de metros cúbicos no período, que corresponde a 48,60% do volume total comercializado. Os produtos analisados corresponderam a quase 36% de todos os produtos comercializáveis pelas principais espécies em volume, e em valor corresponderam a cerca de 70% do total.Palavras-chave: indústria madeireira; madeira tropical; comércio de madeiras. DIAGNOSIS OF THE COMMERCIALIZATION OF SAWN TIMBER IN THE STATE OF MATO GROSSO ABSTRACT: The present study aimed to evaluate the timber trade in the state of Mato Grosso, analyzing the main timber species traded and its main products generated. The data were collected from the reports of Beneficiation and Trade of Madeira Products by Forest Species and made available by the State Secretariat of Environment of Mato Grosso (SEMA-MT). The diagnosis was made between 2007 and 2014, where the total volume, the commercialized values of the ten most traded species and their products were analyzed. The ten most commercialized species (Erisma uncinatum Warm., Goupia glabra Aubl, Qualea albiflora Warm., Qualea paraensis Ducke, Mezilaurus itauba, Qualea sp., Hymenolobium sp., Apuleia sp., Trattinnickia sp. e Vochysia sp.) obtained a value 5.8 billion and an approximate volume of 10.42 million cubic meters in the period, which corresponds to 48.60% of the total volume traded. The products analyzed corresponded to almost 36% of all products traded by the main species in volume, and in value corresponded to about 70% of the total.Keywords: timber industry; tropical wood; timber trade.

International audience; Wood is a widely used material in the construction sector, both in structural and non-structural applications. Tropical species are appreciated for their high quality and durability in furniture, outdoor and indoor claddings and floors. However, limited information exists about fire reaction of tropical wood. Density is one of the factors that influence the rate of pyrolysis reactions and consequently the charring rate. However, other wood characteristics such as the mineral content also exert an influence on the pyrolysis combustion of wood. Hardwoods present a complex morphological structure and a significant amount of minerals, extracts and exudates. In this work, we study the fire reaction of seven species of tropical hardwood using various fire tests. Results are compared from one test to other one and are discussed in relation with physicochemical properties of wood species. The results show that although there is some correlation between high density and ignition time, parameters such as morphology and mineral content are also relevant.

In countries like Costa Rica, there is an interest in developing wooden trusses in a versatile and light way. However, there is a key aspect in the behavior of truss connections in this product. Therefore, the present study determines the structural behavior of the truss connections and the displacement, the resistance, the stiffness values and the failure mode of truss connections made with Gmelina arborea and Tectona grandis timber for angles of 0° and 90°; and three types of truss connectors (metal plates, screws and nails), subject to tension and compression loads. The results showed that metal plates show the highest load values with respect to the nails and screws in both species. Likewise, in the design and critical displacement stress, metal plates surpass the nails and screws in both species; and in the two angles. From these stress values, we proposed a model for the prediction of the stiffness for the truss connections of the intermediate angles (30°, 45° and 60°) and the test showed that the prediction was low, the bias was 3%.

Recently, more wood species are gaining space in market. Hence, it is important to enlarge the utilization of non-traditional woods, which shall be able to replace the most popular species, provided that similar performances are respected. In contrast, the sustainable exploitations of natural resources by timber producers demand alternatives to exchange the use of restricted or blocked tropical wood species (e.g. Araucaria angustifolia) by other timbers, which are liable for commercial certification. This research, based on the test results obtained according to the Brazilian Standard prescriptions (NBR-7190 - Annex B), aimed at evaluating the influence of the apparent density on radial and tangential shrinkages, considering the results for forty-three Brazilian tropical wood species. Usually, this parameter is regarded as necessary to define the timber species to different applications. The results showed low dependence among those variables, considering the information from the literature.

Studies on root wood anatomy are scarce, mainly due to the lack of commercial interest and the difficulty to collect. In Brazilian Cerrado, local craftsmen use root wood for marquetry, the manufacture of such small items as lampshades or ornaments, and table bases. However, taxonomy based on root wood can serve as a guide toward the conservation and management of tree stocks in urban environment. Therefore, we herein describe the root wood anatomy of 14 tree species that occur in the Brazilian Cerrado. To accomplish this, we studied samples from main sinker root, at a depth of about 20 cm, from 37 trees aged 5 to 10 years. Anatomical procedures followed the standard techniques for preparation and analyses of wood samples. We used stem or branch samples from other studies to carry out anatomical description and comparison. However, we encountered some problems, such as: difficulty to distinguish growth rings, sample processing and, in some cases, sample description, since quantity, distribution and type of axial parenchyma differed substantially from that of the main stem. Nonetheless, we did find a variation in the presence/absence of septate fibers among the samples, and noted differences in ray composition., Los estudios sobre la anatomía de la madera de raíz son escasos, principalmente por la falta de interés comercial y la dificultad de recolección. En el Cerrado brasileño, los artesanos locales utilizan la madera de raíz para la marquetería, la fabricación de objetos pequeños como pantallas de lámparas o adornos, y la base de la mesa. Sin embargo, la taxonomía basada en la madera de raíz puede servir como una guía para la conservación y el manejo de las reservas de árboles en entornos urbanos. Por lo tanto, se describió la anatomía de la raíz de la madera de 14 especies de árboles que se encuentran en el Cerrado brasileño.Se estudiaron muestras de la raíz principal, a una profundidad de aproximadamente 20 cm, de 37 árboles de 5 a 10 años. Los procedimientos anatómicos siguieron las técnicas estándar para la preparación y el análisis de muestras de madera. Se utilizaron muestras de tallo o rama de otros estudios para llevar a cabo la descripción anatómica y la comparación. Sin embargo, se encontraron algunos problemas, tales como: los anillos de crecimiento difíciles de distinguir; además, era problemático procesar la muestra y, en algunos casos, describirla dado que la cantidad, distribución y tipo de parénquima axial difería sustancialmente de la del tallo principal. No obstante, se encontró una variación en la presencia/ausencia de fibras septadas entre las muestras, y también diferencias en la composición de los radios.

Ground contact speeds up timber decay because of the large number of microorganisms in soil. This study, we assessed the natural durability of seven tropical species using the European standard EN-807 (2001). We embedded samples of Dalbergia granadillo, Cordia elaeagnoides, Swietenia humillis, Tabebuia donell-smithii, Hura polyandra, Enterolobium cyclocarpum and Tabebuia rosea and temperate species Fagus sylvatica (as a control) in sandy, clay-sandy-loam and clay-loam for 8, 16, 24 and 32 weeks. We evaluated durability of the samples by determining the mass loss and modulus of elasticity (MOE) loss. The results varied significantly (p < 0,001) depending on timber species and soil type considered. The D. granadillo and C. elaeagnoides were the most durable, with mass losses of 4,5%; 6,5% and MOE losses of 4,5%; 20,5%; respectively. F. sylvatica, T. rosea and E. cyclocarpum samples were the least durable, with mass losses of 22,3-25% and MOE losses of 35,8-59,8% respectively. Decay was most aggressive in sandy-clay-loam soil followed by the clay-loam soil and finally the sandy soil.

Resumo A procura intensa por essências madeireiras nativas consolidadas, que apresentam elevado uso, pode ocasionar a superexploração de espécies e diminuição do seu estoque na floresta. Uma alternativa para essa situação é a substituição dessas espécies por outras com propriedades da madeira semelhantes e com suficiente estoque de crescimento na floresta. O objetivo deste trabalho foi agrupar as espécies da Amazônia através das propriedades físico-mecânicas da madeira e realizar a análise discriminante para identificar quais características tecnológicas são mais importantes para o agrupamento. As espécies estudadas foram provenientes de oito localidades distintas da região amazônica. As propriedades físico-mecânicas utilizadas obtidas da literatura especializada nacional foram: densidade básica, contração (tangencial, radial e volumétrica), flexão estática, compressão paralela e perpendicular às fibras, dureza Janka paralela e transversal, tração perpendicular às fibras, fendilhamento e cisalhamento. Foi utilizada a técnica de análise multivariada de Cluster (distância euclidiana simples e o método de Ward) e a análise discriminante para avaliar o agrupamento. A análise de Cluster foi eficiente para agrupar as espécies, que foram separadas em três grupos distintos. As espécies que se destacaram foram a Helicostylis pedunculata Benoist. e Tachigali chrysophylla (Poepp.) Zarucchi & Herend., por se agruparem com as espécies mais comercializadas. Os menores valores de Wilks’Lambda foram da densidade da madeira (0,759053), cisalhamento (0,802960) e compressão paralela às fibras (0,825594). Essas características foram as mais determinantes para discriminar os grupos. A análise de agrupamento é eficiente para indicar a substituição de espécies consolidadas na Amazônia. Abstract The intense search for consolidated native wood essences, which are highly used, can lead to the overexploitation of species and decrease their stocks in the forest. An alternative to this situation is the replacement of these species by others with similar wood properties and with sufficient forest growing stock. The objective of this work was to cluster the Amazon species through wood physical-mechanical properties and perform the discriminant analysis to identify which technological characteristics are more important for the clustering. The species studied came from eight different locations in the Amazon region. The properties used were: basic density, contraction (tangential, radial and volumetric), static flexion, compression parallel and perpendicular to the fibers, Janka hardness parallel and transversal, traction perpendicular to the fibers, cracking and shearing, all obtained from the national specialized literature. Multivariate Cluster analysis (simple Euclidean distance and Ward’s method) and the discriminant analyses were used to evaluate the clustering. Cluster analysis was efficient to cluster the species, which were separated into three distinct groups. The species that stood out were Helicostylis pedunculata Benoist. and Tachigali chrysophylla (Poepp.) Zarucchi & Herend., f or clustering with the most commercialized species. The lowest values of Wilks’Lambda were wood density (0.759053), shearing (0.802960) and compression parallel to the fibers (0.825594). These characteristics were the most determinant to discriminate the clusters. The clustering analysis was efficient for the separation of the species into marketing clusters.

RESUMO Esse trabalho teve como objetivo avaliar o potencial de uso da madeira de quatro espécies tropicais da Amazônia na produção de compósitos madeira-cimento pelo método de adensamento por vibro compactação. As partículas de madeira foram produzidas a partir de costaneiras das espécies Murici (Byrsonima crispa), Ingá vermelho (Inga paraensis), Ingá (Inga alba) e Mata-Matá (Eschweilera odora). Todas as espécies foram consideradas aptas para a produção de compósitos de acordo com o teste Fator CA . Foram testadas as propriedades físicas (densidade, absorção de água e inchamento em espessura) e mecânicas (ligação interna, flexão estática e resistência à compressão) dos compósitos. A densidade da madeira e o tamanho de suas partículas influenciaram a densidade final do compósito e suas propriedades de absorção de água e o módulo de elasticidade. A área superficial da partícula também afetou negativamente a resistência à compressão do material. Tanto o método quanto a madeira apresentaram potencial para fabricação de compósitos com possíveis aplicações como materiais de preenchimento na construção civil ABSTRACT The aim of this work was evaluate the potential use of timbers from four tropical Amazonian species for production of wood-cement composites by vibro-compaction densification method. Wood particles were made from slab wood of Murici (Byrsonima crispa), Red Inga (Inga paraensis), Inga (Inga alba) e Mata-Mata (Eschweilera odora). All species were considered suitable for composites production according to the CA Factor test. Composites physical (density, water absorption and thickness swelling) and mechanical (internal bond, static bending and compressive strength) properties were evaluated. Wood density and particle size influenced the composites final density and their water absorption and modulus of elasticity properties. The particle surface area also affected negatively the material's axial compressive strength. Method and wood showed potential for production of composites with possible application as filling materials in civil construction.

SUMMARY: Studies on root wood anatomy are scarce, mainly due to the lack of commercial interest and the difficulty to collect. In Brazilian Cerrado, local craftsmen use root wood for marquetry, the manufacture of such small items as lampshades or ornaments, and table bases. However, taxonomy based on root wood can serve as a guide toward the conservation and management of tree stocks in urban environment. Therefore, we herein describe the root wood anatomy of 14 tree species that occur in the Brazilian Cerrado. To accomplish this, we studied samples from main sinker root, at a depth of about 20 cm, from 37 trees aged 5 to 10 years. Anatomical procedures followed the standard techniques for preparation and analyses of wood samples. We used stem or branch samples from other studies to carry out anatomical description and comparison. However, we encountered some problems, such as: difficulty to distinguish growth rings, sample processing and, in some cases, sample description, since quantity, distribution and type of axial parenchyma differed substantially from that of the main stem. Nonetheless, we did find a variation in the presence/absence of septate fibers among the samples, and noted differences in ray composition. RESUMEN: Los estudios sobre la anatomía de la madera de raíz son escasos, principalmente por la falta de interés comercial y la dificultad de recolección. En el Cerrado brasileño, los artesanos locales utilizan la madera de raíz para la marquetería, la fabricación de objetos pequeños como pantallas de lámparas o adornos, y la base de la mesa. Sin embargo, la taxonomía basada en la madera de raíz puede servir como una guía para la conservación y el manejo de las reservas de árboles en entornos urbanos. Por lo tanto, se describió la anatomía de la raíz de la madera de 14 especies de árboles que se encuentran en el Cerrado brasileño. Se estudiaron muestras de la raíz principal, a una profundidad de aproximadamente 20 cm, de 37 árboles de 5 a 10 años. Los procedimientos anatómicos siguieron las técnicas estándar para la preparación y el análisis de muestras de madera. Se utilizaron muestras de tallo o rama de otros estudios para llevar a cabo la descripción anatómica y la comparación. Sin embargo, se encontraron algunos problemas, tales como: los anillos de crecimiento difíciles de distinguir; además, era problemático procesar la muestra y, en algunos casos, describirla dado que la cantidad, distribución y tipo de parénquima axial difería sustancialmente de la del tallo principal. No obstante, se encontró una variación en la presencia/ausencia de fibras septadas entre las muestras, y también diferencias en la composición de los radios.

The evaluation of forest composition is a very important stage of forest management. This evaluation is done through forest inventories. The objective of this work is to present the results of a 100% forest inventory make in areas of forest exploitation of small farmers under logging management, located in the municipality of Senador Guiomard, in the state of Acre, in the Brazilian Amazon. The inventoried area (206.8 ha), in which all the trees with DBH  50.0 cm were measured, revealed a total number of trees (NT) of 3,518, abundance (AB) of 17.01 trees ha-1, total volume (VT) of 21,667.41 m3, volume per hectare (V) of 104.77 m3 ha-1, total basal area (ABsT) of 1,413.77 m2 and basal area per hectare (ABs) of 6.84 m2 ha-1. A total of 204 species belonging to 136 genera and 43 botanical families were recognized in the field. The five species of highest Index of Importance of Species (IND) were: Brazil nut (Bertholletia excelsa Bonpl.), Tauari (Couratari macrosperma A.C. Sm.), Cumaru-cetim (Apuleia molaris Spruce ex Benth.), Rubber tree (Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg.) and Cumaru-ferro (Dipteryx odorata (Aubl.) Willd.). The sum of the IND of these five represents a third (33.6%) of the total IND (all species). Most of the 20 species with the highest IND are loggers of commercial use and represents for about 60% of the total IND. This study showed a significant concentration of the dendrometric elements, that is, few species unit most of the adult trees and, consequently, most of the timber volume. Entre as etapas fundamentais do manejo florestal está a avaliação da composição da floresta. Essa avaliação é feita por meio de inventários florestais. Este trabalho tem como objetivo apresentar resultados de um inventário florestal a 100% realizado em talhões de colheita de pequenas áreas sob manejo florestal madeireiro, localizadas em Senador Guiomard-AC. A área inventariada, de 206,8 ha, em que foram abordadas todas as árvores com DAP  50,0 cm, revelou um número total de árvores (NT) de 3.518, abundância (AB) de 17,01 árvores ha-1, volume total (VT) de 21.667,41 m3, volume por hectare (V) de 104,77 m3 ha-1, área basal total (ABsT) de 1.413,77 m2 e área basal por hectare (ABs) de 6,84 m2 ha-1. Foram reconhecidas 204 espécies, pertencentes a 136 gêneros e a 43 famílias botânicas. As cinco espécies de maior Índice de Importância da Espécie (IND) foram: Castanheira (Bertholletia excelsa Bonpl.), Tauari (Couratari macrosperma A.C. Sm.), Cumaru-cetim (Apuleia molaris Spruce ex Benth.), Seringueira (Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg.) e Cumaru-ferro (Dipteryx odorata (Aubl.) Willd.). Estas cinco espécies representaram um terço (33,6%) do IND total. A maioria das 20 espécies com maior IND são madeireiras de uso comercial e responderam por cerca de 60% do IND total. Os resultados mostraram expressiva concentração dos elementos dendrométricos, ou seja, poucas espécies reúnem a maior parte das árvores adultas e, conseqüentemente, a maior parte do volume madeireiro. Made available in DSpace on 2019-04-17T01:12:32Z (GMT). No. of bitstreams: 1 26792.pdf: 762605 bytes, checksum: 4ced4b598f127d0f9cc230bc20be15e0 (MD5) Previous issue date: 2019

During the 16th and 17th century wood species used for woodwind instruments were plum, cherry, pearwood, ebony, boxwood, lignum vitae, and maple for larger instruments. During the 18th century fruitwood species were chemically treated with dyes or acids to have darker color and to be a substitute of ebony. Since the beginning of the 19th century tropical woods such as rosewood, cocuswood, satinwood were used for very fine small instruments rather then maple which was used mostly for bassoon made in Germany. In France, for the bassoon, rosewood was preferred to maple. Boxwood of British and Turkish origins having a high dimensional stability was employed for fine quality flutes. Early clarinets were made of plumwood, pearwood and maple. African blackwood was accepted as the best material of manufacture for oboe, clarinets, wooden flutes and piccolos. Giving the limited resources of tropical wood species for wind instruments, some efforts were oriented toward other substitutive species. This chapter summarizes physical, mechanical and acoustical properties of species commonly used for woodwind instruments.

This aim of this work is to present an analysis of the influence of impregnation against biological demand, realized with saline solution of CCB (Chromated Copper Borate preservative) by vacuum-pressure process, on physical-mechanical properties of tropical wood species Simarouba sp., Cedrelinga catenaeformis and Erisma uncinatum Warm. In theory, such process could increase the number of surface defects in wood pieces and reduce its strength properties. To investigate this influence, the complete species characterization was carried out in two conditions (without treatment and CCB treated wood). Tukey’s multiple comparisons test (5% significance level) was applied. In addition, scanning electron microscopy (SEM) photomicrographs were obtained with the energy dispersive spectroscopy (EDS) to investigate preservative presence at the cellular level. Results permitted to conclude that CCB impregnation process did not affect physical-mechanical properties of the studied species.

O objetivo do estudo foi analisar a predição da distribuição de espécies florestais madeireiras, em escala local, utilizando dados de ocorrência agrupados por classe diamétrica. Para estimar a distribuição foi utilizado o método de máxima entropia (Maxent) e as ocorrências são de inventário florestal de planos de manejo. As variáveis preditoras dos modelos foram:altitude, declividade, distância vertical à drenagem mais próxima (HAND), índice de vegetação por diferença normalizada (NDVI) e densidade de pontos das espécies florestais. Foram selecionadas seis variáveis preditoras, por espécie, pelo método de todas as regressões possíveis. Os modelos tiveram em média bom desempenho (AUC = 0,7; taxa de omissão = 8,8%), demonstrando a viabilidade de se predizer a distribuição de espécies por classe diamétrica. As variáveis mais importantes foram altitude, NDVI e densidade. De acordo com os modelos, as árvores de Astonium lecointei, Clarisia racemosa e Ceiba pentandra com diâmetro a altura do peito (DAP) ? 100 cm têm maior probabilidade de ocorrer em ambientes localizados em altitudes mais elevadas do terreno. Esse procedimento de modelagem é eficiente para ampliar o conhecimento sobre as preferências de habitat e a distribuição geográfica de espécies na paisagem em função do DAP. The aim of the study was to analyze the prediction of the distribution of forest tree species, on a local scale, using occurrence data grouped by diameter class. To estimate the distribution of species the maximum entropy method (Maxent) and the occurrence data are forest management plan was used. The predictor variables were: elevation, slope, height above the nearest drainage (HAND), and normalized difference vegetation index (NDVI) and dot density of forest species. Six predictor variables were selected by species by method of all possible regressions. The models, by species and diameter class, had an average good performance (AUC = 0.7; omission rate = 8.8%), demonstrating the viability of predicting the distribution of species by diameter class. The most important predictor variables were altitude, NDVI, densities Amburana acreana and Clarisia racemosa. However, further studies are needed to clarify whether there is an interaction between forest species or share the same habitat. According to the models, trees of the species Astonium lecointei, Clarisia racemosa and Ceiba pentandra with diameter at breast height (DBH) ? 100 cm are more likely to occur in localized higher elevations. This modeling procedure is efficient to increase knowledge about habitat preferences and geographical distribution of species in the landscape by DBH. Made available in DSpace on 2019-12-19T00:34:52Z (GMT). No. of bitstreams: 1 26929.pdf: 1357616 bytes, checksum: d00dd34d8f673078ec0ae75017034169 (MD5) Previous issue date: 2019

International audience; Variability in the chemical composition of 614 species is described in a database containing measurements of wood polymers (cellulose, lignin andpentosan), as well as overall extraneous components (ethanol-benzene, or hot water extracts and ash, with a focus on silica content). These measurements were taken between 1945 and 1990 using the same standard protocol. In all, 1,194 trees belonging to 614 species, 358 genera and 89 families were measured. At species level, variability (quantified by the coefficient of variation) was rather high for density (27%), much lower for lignin and cellulose (14% and 10%) and much higher for ethanol/benzene extractives, hot water extractives and ash content (81%, 60% and 76%). Considering trees with at least five different specimens, and species with at least 10 different trees, it was possible to investigate within-tree and withinspecies variability. Large differences were found between trees of a given species for extraneous components, and more than one tree should be needed per species. For density, lignin, pentosan and cellulose, the distribution of values was nearly symmetrical, with mean values of 720 kg/m3 for density, 29.1% for lignin, 15.8% for pentosan, and 42.4% for cellulose. There were clear differences between species for lignin content. For extraneous components, the distribution was very dissymmetrical, with a minority of woods rich in this component composing the high value tail. A high value for any extraneous component, even in only one tree, is sufficient to classify the species in respect of that component. Siliceous woods identified by silica bodies in anatomy have a very high silica content and only those species deserve a silica study.; La variabilité de la composition chimique de 614 espèces est décrite dans une base de données contenant des mesures de polymères du bois (cellulose, lignine et pentosane), ainsi que de l’ensemble des composants externes (extraits éthanolbenzéne ou à l’eau chaude et cendres, en particulier la teneur en silice). Ces mesures ont été effectuées entre 1945 et 1990 selon le même protocole standard. Au total, 1 194 arbres appartenant à 614 espèces, 358 genres et 89 familles ont été mesurés. La variabilité entre les espèces (quantifiée par le coefficient de variation) était plutôt élevée pour la densité (27 %), beaucoup plus faible pour la lignine et la cellulose (14 % et 10 %) et beaucoup plus élevée pour les extractibles éthanol/benzène, les extractibles à l’eau chaude et les cendres (81 %, 60 % et 76 %). En considérant des arbres avec au moins cinq spécimensdifférents et des espèces avec au moins 10 arbres différents, il a été possible d’étudier la variabilité intra-arbre et intraespèce. De grandes différences ont été constatées entre les arbres d’une espèce donnée pour les composants externes, et plus d’un arbre devrait être nécessaire par espèce. Pour la densité, la lignine, le pentosane et la cellulose, la distribution des valeurs était presque symétrique, avec des valeurs moyennes de 720 kg/m3 pour la densité, 29,1 % pour la lignine, 15,8 % pour le pentosane et 42,4 % pour la cellulose. La teneur en lignine variait nettement d’une espèce à l’autre. Pour les composants externes, la distribution était très dissymétrique, avec une minorité de bois riches en ce composant constituant la queue de valeurs élevées. Une valeur élevée pour tout composant externe, même dans un seul arbre, est suffisante pour classer l’espèce à l’égardde ce composant. Les bois siliceux identifiés par les cristaux de silice en anatomie ont une teneur très élevée en silice et seules ces espèces méritent une étude sur la silice.

The lack of use of the residues generated by the mechanical processing of wood and their inadequate disposal are challenges for the timber industry. They have potential for products with higher value. The purpose of this research was to evaluate the use of residues generated by the mechanical processing of Amazonian woods Caryocar villosum, Hymenolobium excelsum, Mezilaurus lindaviana, Erisma uncinatum, Tachigali myrmecophyla and Qualea paraensis in the high-density particleboard production. The panels produced had nominal density of 850 kg.m-3, nominal thickness of 15.7 mm and 8% of phenol formaldehyde adhesive. The physical-mechanical properties of the panels produced from each species and with a mixture of all of them in equal parts were evaluated. The specimens from the panels were prepared for physical tests (apparent density, moisture content, water absorption and thickness swelling) and mechanical tests (static bending - modulus of elasticity and modulus of rupture, and internal bond) according to the standard ABNT NBR 14810-3. The mechanical properties of the particleboards manufactured with the C. villosum, H. excelsum and T. myrmecophyla residues were generally superior than those of the other species and met one or more of the minimum requirements indicated by the ANSI A208.1 standard for (H-1 classification) and for floors production (PBU classification). RESUMO A falta de aproveitamento dos resíduos gerados pelo processamento mecânico da madeira e seu descarte inadequado são desafios para a indústria madeireira. Esses poderiam ser utilizados em produtos de maior valor agregado. O objetivo deste trabalho foi avaliar a utilização de resíduos gerados pelo processamento mecânico das madeiras amazônicas Caryocar villosum, Hymenolobium excelsum, Mezilaurus itauba, Erisma uncinatum, Tachigali myrmecophyla e Qualea paraensis na produção de painéis aglomerados de alta densidade. Os painéis foram produzidos com massa específica nominal de 850 kg.m-3, espessura nominal de 15,7 mm e adesivo fenol-formaldeído na proporção de 8%. As propriedades físico-mecânicas dos painéis produzidos a partir de cada espécie e de uma mistura entre todas elas em partes iguais foram avaliadas em sete tratamentos. Corpos- de-prova, retirados dos painéis produzidos, foram confeccionados para ensaios físicos (massa específica, teor de umidade, absorção de água e inchamento em espessura) e mecânicos (flexão estática - MoR e MoE, e ligação interna) de acordo com a norma ABNT NBR 14810-3. As propriedades mecânicas dos painéis aglomerados, manufaturados com os resíduos de C. villosum, H. excelsum e T. myrmecophyla foram, de maneira geral, superiores às das demais espécies e atenderam um ou mais dos requisitos mínimos indicados pela norma ANSI A208.1 para painéis de alta densidade (classificação H-1) e destinados a produção de pisos (classificação PBU).

O manejo florestal deve estar apoiado no entendimento da dinâmica da floresta, a fim de garantir a melhor tomada de decisão. A estrutura diamétrica é uma ferramenta adequada, que fornece informações sobre uma determinada espécie ou para a floresta em geral. Assim, neste trabalho, foi avaliada a estrutura diamétrica de três espécies amazônicas: Bertholletia excelsa Bonpl. (Castanheira), Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg (Seringueira) e Swietenia macrophylla King (Mogno) na Floresta Estadual do Antimary, estado do Acre, Brasil. Também foram ajustadas funções de densidade de probabilidade mais comumente utilizadas para representar as distribuições diamétricas de espécies florestais. A espécie B. excelsa apresentou estrutura bimodal com uma grande amplitude diamétrica. H. brasiliensis apresentou distribuição unimodal assimétrica positiva. A baixa ocorrência de S. macrophylla na área de estudo não garante que a distribuição observada seja representativa. A estrutura diamétrica das três espécies é similar às reportadas em outros estudos. Na avaliação das funções de densidade probabilística, os modelos Normal e Weibull foram aderentes para as três espécies. Forest management should be based on understanding the forest dynamics in order to ensure better decision making. The diameter structure is an adequate tool, which provides information about a particular species or the forest in general. Thus, diameter structure of three Amazonian species were evaluated: Bertholletia excelsa Bonpl. (Castanheira), Hevea brasiliensis (Willd. Ex A.Juss.) Müll.Arg (Seringueira) and Swietenia macrophylla King (Mahogany) at Antimary State Forest, Acre State, Brazil. We also fitted probability density functions commonly used to represent the diameter distributions of forest species. B. excelsa presented bimodal structure with a great diameter amplitude. H. brasiliensis presented a unimodal distribution positively skewed. The low occurrence of S. macrophylla in the study area does not guarantee that the observed distribution is representative. The diameter structures of three species are similiar to those reported in other studies. In the evaluation of probabilistic density functions, Normal and Weibull models were adherent to the three species. Made available in DSpace on 2019-11-06T18:09:41Z (GMT). No. of bitstreams: 1 26898.pdf: 688650 bytes, checksum: 5796411eeb6fa3c1f7980a8a0549e4ac (MD5) Previous issue date: 2019

The objective of this study was to evaluate the volumetric lumber yield of four native species of the Amazon Region: Cedrinho (Erisma uncinatum Warm), Cumaru ( Dipteryx odorata Aublet), Garapeira (Apuleia leiocarpa Voguel), and Cambará (Qualea paraensis Ducke). Twelve logs of each species with different diameters were randomly selected from different sawmills in northern Mato Grosso state, Brazil. Additionally, the influence of diameter on the yield of each species was evaluated through regression analysis. Among the evaluated species, Cedrinho obtained the highest yield values, followed by Garapeira. Cumaru and Cambará showed the lowest yields, and did not differ statistically. Log diameter negatively influenced lumber yield, except for Cumaru wood, which did not present a clear relation between these parameters.

Esta pesquisa teve como objetivo avaliar a qualidade de painéis aglomerados produzidos com seis espécies de madeiras tropicais da Amazônia: Byrsonima crispa, Eschweilera coriacea, Eschweilera odora, Manilkara amazonica, Pouteria guianensis e Swartzia recurva. Foram produzidos painéis experimentais com densidade nominal de 0,75 g/cm3, utilizando a resina uréia-formaldeído na proporção de 8% de sólidos - base peso seco das partículas. Os painéis foram prensados com pressão específica de 4,0 MPa, temperatura de 160 ºC e tempo de prensagem de oito minutos. Os painéis foram avaliados com base nas seguintes propriedades: razão de compactação, absorção de água e inchamento em espessura 2 horas e 24 horas, módulos de elasticidade e de ruptura, tração perpendicular, resistência ao arrancamento de parafusos na superfície e topo. A baixa razão de compactação dos painéis produzidos comas espécies tropicais não afetou de forma significativa os resultados de suas propriedades físicas e mecânicas. Avaliações comparativas dos resultados obtidos com os requisitos da norma EN 312 (2003) e espécie referencial - Pinus taeda, demonstraram que as espécies Byrsonima crispa, Eschweilera coriacea, Eschweilera odora e Pouteria guianensis apresentam grande potencial para produção de painéis aglomerados.

Las curvas laminadas fabricadas con chapas vaporizadas permiten obtener radios de curvatura más pequeños que cuando no se aplica este proceso. En este estudio, se presentan el comportamiento de madera de Alnus acuminata, Tectona grandis, Gmelina arborea, Terminalia oblonga, Alnus acuminata y Swietenia macrophylla provenientes de plantaciones de rápido crecimiento en la fabricación de curvaturas con radios de (4, 6, 8, 10, 12 y 14) cm. Fue posible obtener radios de curvaturas de 4 cm, a excepción de T. grandis de donde solo fue posible obtener radio de 6 cm. El proceso de vaporizado aumentó el contenido de humedad de la chapa en un rango de 3.3% a 10.2%. El adhesivo permite que el radio de la curva fabricada se mantenga en radios menores a 10 cm y en radios de 12 cm y 14 cm la curva tiende a abrirse (máximo 1%), para todas las especies, no obstante, la abertura se estabiliza al día 4 luego de fabricada. Las delaminaciones de las chapas se producen principalmente en los radios de 4 cm a 8 cm y se presentan con mayor incidente en la T. grandis y T. oblonga. La resistencia en cizallamiento de 7,5 MPa-11,2 MPa y no se alteró al someter a pruebas de envejecimiento, pero hay una mayor delaminación en todas las especies.

EFICIENCIA DO OLEO QUEIMADO COMO PRESERVATIVO DE MADEIRAS SUBMETIDAS A ENSAIOS DE DETERIORACAO DE CAMPO O objetivo desse estudo foi avaliar a eficiencia do oleo queimado como preservativo de madeiras de Trattinnickia rhoifolia Willd. submetidas a ensaios de deterioracao de campo. Os tratamentos preservativos com oleo queimado foram realizados pelo metodo de imersao simples considerando dois fatores de variacao: viscosidade do oleo (SAE 10 e SAE 15) e tempo de imersao (3 min, 3 h e 24 h). A eficiencia dos tratamentos preservativos foi avaliada por meio da taxa de retencao do produto oleoso, quantificacao da lixiviacao apos exposicao em campo e perda de massa causada pela deterioracao biologica. Adicionalmente, foi empregada a tecnica de colorimetria para avaliacao do escurecimento causado pelo tratamento preservativo e no monitoramento da alteracao da cor superficial da madeira devido a lixiviacao pela exposicao a campo. Com base nos resultados pode-se concluir que o tratamento preservativo com oleo queimado foi eficiente, de modo a proporcionar as madeiras uma maior resistencia biologica, com destaque para o uso do oleo de menor viscosidade (SAE 10). As maiores taxas de retencao e menores perdas de massa devido a deterioracao biologica foram obtidas ao empregar o oleo queimado SAE 10, por outro lado tambem apresentaram as maiores taxas de lixiviacao. Palavras-chave: preservacao da madeira, imersao simples, preservativo oleoso, madeira tropical. ABSTRACT The objective of this study was to evaluate the efficiency of oil burned as a wood preservative of Trattinnickia rhoifolia Willd submitted to field deterioration tests. The preservatives treatments with burnt oil were performed by the simple immersion method considering two variation factors: oil viscosity (SAE 10 and SAE 15) and immersion time (3 min, 3 h and 24 h). The effectiveness of the preservative treatments was evaluated through oily product retention rate, quantification of leaching after exposure in the field and mass loss caused by biological deterioration. Additionally, the colorimetric technique was used to assess the darkening caused by preservative treatment and monitoring of the change of surface color of the wood due to leaching by exposure to the field. Based on the results, it can be concluded that the preservative treatment with burnt oil was efficient, to provide the woods a greater biological resistance, especially the use of the oil with lower viscosity (SAE 10). The higher retention rates and low mass loss due to biological deterioration were obtained when employing the burnt oil SAE 10, and on the other hand also showed the highest rates of leaching. Keywords: wood preservation, simple immersion, oily preservative, tropical wood. DOI: http://dx.doi.org/10.14583/2318-7670.v04n03a04

Wood is a renewable material, presenting wide use in building construction. For its better employability, it is necessary to perform physical and mechanical characterization of the several species available for application. In this respect, Brazilian Code ABNT NBR 7190:1997 - Timber Structures Design, in its Annex B, prescribes the proper tests and adds some relations between properties and strength classes for coniferous and dicotyledonous. The strength classes are function of characteristics values of strength in compression parallel to grain (fc0). However, density is a more easy-determination property and the cited Code presents the mean value of density for each strength class. Therefore, this research aimed to evaluate the possibility of inferring fc0 based on density obtained on tests of three Brazilian tropical wood species: Canafistula (Cassia ferruginea); Angelim araroba (Vataireopsis araroba) e Castelo (Gossypiospermum sp.). Statistical procedures shown it is possible to conclude that, in some cases, density is not a good estimator of fc0.

Acoustic properties such as specific dynamic Young’s modulus (Ed/γ), internal friction (Q-1), and acoustic conversion efficiency (ACE) of wood are important properties frequently examined using free-free flexural vibration. This study determined the suitability for making musical instrument soundboards and frameboards from four tropical wood species; namely Syzygium, Dialium, Gymnostoma, and Sindora. The results show that (Ed/γ), (Q-1), and ACE were in the range of 20.0 to 28.9 GPa, 0.0031 to 0.0085, and 3.41×107 to 10.83×107, respectively. Based on the results, Syzygium was preferred for making the frameboard of violins and guitars. The outer sapwood (outer part) of Syzygium was the most suitable for making frameboard by considering the lowest ACE and highest Q-1. Based on Ed/γ, the inner sapwood (middle part) in Dialium was the most suitable for making soundboard, but based on Q-1 and ACE, heartwood (inner part) was the most preferred for making soundboard. Gymnostoma was also preferred for making soundboard of violins and guitars (inner sapwood) because it yields the highest mean value of Q-1 and ACE. Considering ACE and Q-1, the outer sapwood in Sindora was the best for making frameboard. When considering Ed/γ and Q-1, the heartwood is the most suitable for making the frameboard of violins and guitars.

Wood is a natural resource that is renewable and available in various species in tropical countries. Its abundancy in nature makes it easy to obtain, thus making it a nature friendly material for use in construction. Indonesia is the most important source of tropical wood in the world after Brazil, making the use of wood for structural elements very desirable. It is estimated that 4000 different varieties of wood exist in Indonesia. This estimate is based on the herbarium species collected by the Forestry Research Institute, currently counting nearly 4000 types of trees with a diameter of more than 40 cm. In the Indonesian wood structure code, the strength of woods is divided into 3 grades (grade I, II and III). This paper presents an evaluation of the mechanical properties of glulam wood sourced from native Indonesian timber: Bengkirai wood (grade I), Kamper wood (grade II), and Nyatoh wood (grade III), thus proving the potential for Indonesian wood as industrial structural elements in wooden constructions.