973 resultados para wood use
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X-rays were initially used for the inspection of special-purpose wood pieces for quantitative evaluation properties of different species. X-ray densitometry has had its use expanded ill dendroclimatology of Picea engelmannii trees. Subsequent laboratories developed applications of X-ray densitometry for environmental, wood science and technology, and related areas. This paper describes the basic methodology of X-ray densitometry applied to the eucalypt wood analysis, as well its presenting the results of applications in three areas: (i) evaluation of wood biodegradation by white rot fungi, (ii) detection of sapwood and heartwood, and (iii) determination of the effect of management oil wood properties. The wood decayed by white rot fungi was detected by X-ray densitometry with it decreasing wood density due to the biodegradation of cell wall components. The sapwood and heartwood of eucalypts were separated in response to the attenuation of X-rays, reflected by the wood anatomical structure and chemical composition. Also, Ill eucalypt trees after the application of irrigation and i characteristic wood density profiles were detected. Ill addition, the significant potential of X-ray densitometry for eucalypt wood research and analysis is discussed.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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More than 130 organic substances in dichloromethane-methanol (4: 1) extracts of particulate matter and the gaseous phase from wood burning for the production of charcoal have been identified by capillary gas chromatography coupled with low-resolution mass spectrometry (GC-MS), use of GC retention indices, and comparison with authentic standards. Many of the substances identified are methoxyphenols (derivatives of syringol and guaiacol), polycyclic aromatic hydrocarbons (PAH), oxidized PAH (oxy-PAH), and levoglucosan, the last being a monosoccharide derivative from the thermal breakdown of cellulose. The amount of unsubstituted PAH was greater than that of methyl- and dimethyl-substituted homologs.
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The quantity and distribution of vegetal biomass are important aspects to consider in ecosystem studies. However, little information is available about Brazil's Pantanal woodland savannas. This work involved the development of regression equations of the aerial biomass and wood volume of native tree species in a region of woodland savanna on Rio Negro farm in the Pantanal of Nhecolandia, Brazil. Samples were taken from 10 trees of each of five species: Protium heptaphyllum (Aub1.) Marchand, Magonia pubescens A. St.-Hil., Diptychandra aurantiaca Tul., Terminalia argentea Mart. and Zucc. and Licania minutiflora (Sagot) Fritsch and from a miscellaneous group of I I different species. Linear and nonlinear regression analyses were developed relating the diameter at breast height to the dry weight of wood, branches and leaves, wood volume and total aerial biomass. All the regressions showed a significance of P < 0.05 and an R-2 close to or above 0.8. The biomass curve predicted by linear regression analysis of the studied species was similar to the nonlinear regression, with the exception of L. minutiflora and the miscellaneous group. The breast height diameter proved a good choice for estimating biomass and wood volume. The estimated wood volume and biomass of the Pantanal woodland savanna is crucial information for understanding the carbon cycle and for ensuring the region's conservation and sustainable use. (c) 2006 Elsevier B.V. All rights reserved.
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The majority of the Brazilian schools of Civil Engineering have taught the subject works with wood in the traditional only by disciplines of Metallic Structures and Wood at a topic in the content of the program on disciplines at the Materials of Civil Construction. To extend of the wood studies is being made possible that all the pupils have a wider understanding of this material and its adapted use is the goal of the proposal, that by the means of the education modality e-learning, disclosing the first one: Module I - Introduction to the Study of the Wood. This methodology tries to use the theoretical beddings in projects that are related to the pupil daily tasks and its practical professional. The article presents the theoretical bases of the conception proposal and its structure, and at the conclusions, the problems found during its application are displayed. Basically, the methodology considers that the professor and the pupil must share the learning, and adopt it as main in the interdisciplinary.
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Two discussions are imposed to the designers of wood constructions. The first one deals with the technical knowledge to project and execute buildings; the second one is concerned with the preservation of the environment, use of the wood in a sustainable way. The work presents the tendencies of the wood used in the Brazilian habitation architecture characterizing the used woods; how the construction technical solutions have developed and discusses about the necessity of using the wood in a conscious way, knowing its origin and control, sustainable use of the forests resources. It focalizes, mainly, the search of the designers to harmonize the use of the wood and the preservation of the forest biodiversity, when it deals with the native forest.
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More than 80% of the 29600 km of the Brazilian railroad mesh employs wooden sleepers. The problem of hard availability of native wood for this purpose leads to the alternative use of reforestation species to produce sleepers. Considering the great difficulty to, in field condition, evaluate characteristics that are of major importance to define its suitability to sleeper production the Research Group on Forest Products from FCA/UNESP - Brazil had developed equipment for field evaluation of hardness in wood - Portable Hardness Tester. This paper reports the functional validation tests, performed with different species of Eucalyptus. Results revealed the equipment great functionality, easy-to-use characteristics and applicability to Eucalyptus wood. Moderate to strong relationships between laboratory and validated values of hardness were found. The best validation model was obtained using the data provided by the experimental dispositive 3 (R2=0.74 and SSE= 7.71 kJ/m2) while the experimental dispositive 1 gave the worse validation (R2=0.55 and SSE= 13.46 kJ/m2).
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The purpose of this study was to evaluate the physical and mechanical properties of particleboard made with pruning wastes from Ipê (Tabebuia serratifolia) and Chapéu-de-Sol (Terminalia catappa) trees. Particleboards were prepared with both wood species, using all the material produced by grinding the pruning wastes. The particleboards had dimensions of 45×45 cm, a thickness of approximately 11.5 mm and an average density of 664 kg/m3. A urea-formaldehyde adhesive was used in the proportion of 12% of the dry particle mass. The particleboards were pressed at a temperature of 130 C for 10 mins. The physical and mechanical properties analyzed were density, moisture content, thickness swelling, percentage of lignin and cellulose, modulus of resilience, modulus of elasticity and tensile strength parallel to the grain, accordingly to the standards NBR 14810 and CS 236-66 (1968). The particleboards were considered to be of medium density. The particle size significantly affected the static bending strength and tensile strength parallel to the grain. Ipê presented better results, demonstrating a potential for the production and use of particleboard made from this species. © The Author(s) 2013.
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The inadequate and indiscriminate disposal of sugarcane vinasse in soils and water bodies has received much attention since decades ago, due to environmental problems associated to this practice. Vinasse is the final by-product of the biomass distillation, mainly for the production of ethanol, from sugar crops (beet and sugarcane), starch crops (corn, wheat, rice, and cassava), or cellulosic material (harvesting crop residues, sugarcane bagasse, and wood). Because of the large quantities of vinasse produced, alternative treatments and uses have been developed, such as recycling of vinasse in fermentation, fertirrigation, concentration by evaporation, and yeast and energy production. This review was aimed at examining the available data on the subject as a contribution to update the information on sugarcane vinasse, from its characteristics and chemical composition to alternatives uses in Brazil: fertirrigation, concentration by evaporation, energy production; the effects on soil physical, chemical and biological properties; its influence on seed germination, its use as biostimulant and environmental contaminant. The low pH, electric conductivity, and chemical elements present in sugarcane vinasse may cause changes in the chemical and physical-chemical properties of soils, rivers, and lakes with frequent discharges over a long period of time, and also have adverse effects on agricultural soils and biota in general. Thus, new studies and green methods need to be developed aiming at sugarcane vinasse recycling and disposal. © 2013 Elsevier Ltd. All rights reserved.
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This paper presents a research on the environmental impacts of particleboards produced from wastes, based on a comparative Life Cycle Assessment study. The particleboards were manufactured in laboratorial scale from the following residues: sugarcane bagasse (Saccharum spp.) and pine wood shavings (Pinus elliottii). The study was developed following the methodological guidelines of ISO 14040. The functional unit adopted was the m2 of the particleboards produced and the impacts were evaluated by the Environmental Development of Industrial Products method. The results indicated that pine particleboard present the highest environmental impact potential. Our findings suggested that the factors that mostly aggravated the environmental impacts were: the distance between the raw materials and the production site, and formaldehyde emissions (FE). The first is related to the combustion of fossil fuel during the acquisition of raw material, which achieved the values of 2185.94 g/m2 for consumption of non-renewable resources for pine particleboard and 893.53 g/m2 for bagasse particleboard. The second is related to the use of urea-formaldehyde resin, responsible for the FE into the air during production. The FE is accountable for the contamination of approximately 7,800,000.00 m3 of air per m2 of particleboard produced, and was the factor with the greatest impact in human toxicity potential. © 2013 Elsevier Ltd. All rights reserved.
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The identities and quantities of the phenolic compounds and coumarins in twelve samples of sugar cane spirit aged in Quercus sp., Amburana cearensis, Cariniana legalis, Castanea sativa Mill, Ocotea sp., Cotyledon orbiculata L., and Hymenaea sp. casks were determined. These compounds have a direct influence on the sensory characteristics of aged beverages; some of them are considered to be markers for the aging process. The analysis of phenolic compounds was performed by HPLC. Solid phase extraction (SPE) was also used for the determination of coumarins. The concentrations of the principal compounds extracted varied according to the species of wood. The concentrations of total phenolic compounds ranged from 0.08 for a sample stored in a 4000-L jatobá barrel for a period of six months to 40.9 mg · L−1 for a sample aged in a 50000-L oak barrel for a period of 48 months. The use of the SPE technique removed interfering compounds from the samples, thereby improving the detection of coumarin.
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Recycled polymer matrix composites reinforced with wood flour can be a viable alternative for the replacement of wood and virgin polymers in materials used in floors, door frames, windows and external cladding. The objective of this research was to determine some physical and mechanical parameters of composite made with Pinus taeda and elliottii wood flour (WF) and recycled polypropylene (PP), without the use of compatibilizers or additives. The composites were separated into four traits, namely 100% PP, 90% PP with 10%, WF 80% PP with 20% WF and 70 % PP with 30% WF. The characterization of the composite followed the standards ASTM D-638-10, ASTM D256-00, ASTM D570 -98, ASTM D1238 -10 and ASTM G 155-05, it was also employed the surface analysis by scanning electron microscopy. The dimensional stability tests showed satisfactory results. Even the composite with a higher percentage of wood flour (30%) had a flow index of 10 MFI, considered compatible with that observed for PP (polypropylene) virgin by standard ASTM D 1238-10. The inclusion of wood flour (FM) afforded composites with good mechanical characteristics which can be applied in manufacture of different materials, specifically employed outdoors.
Production and Use of Heteroptera Predators for the Biological Control of Eucalyptus Pests in Brazil
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The need for housing in Brazil is very large, and despite government efforts to address this issue, the housing deficit is too large. When analyzing markets without this problem, it is concluded that one of the factors that influence this model is the construction adopted by Brazilian society that is in masonry. Alternatively, the system can be used in constructive Wood-frame. To apply this system in Brazil, one can say that the workmanship and the materials available to meet the demand would be created in a short period of adjustments and capabilities, but identifies himself as one of the biggest problems the planning and management of works. And one of the tools for solving this problem is to use a checklist of the activities of constructive process, avoiding forgetting or not aware of the activities necessary to complete the project