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Paulo Fernando Trugilho,José Tarcísio Lima,Fábio Akira Mori,Ana Luiza Lino
CERNE , 2001,
Abstract: Charcoal is economically representative in the Brazilian economy, specially in Minas Gerais, the main producer, and consumer of this product. A problem related to the charcoal utilization is its heterogeneous quality, which is influenced both for the wood and the production process. This variability causes waste of material and make it difficult to handle the blast furnaces. The objective of this work was to evaluate the wood of ten clones: seven of Eucalyptus grandis and three of Eucalyptus saligna: both directed to charcoal production. Also, it was looked for to select clones with highercapacity for the establishment of a forestry improvement program. During the assessment it was considered the quantitative and qualitative characteristics of the charcoal. According to the results it was verified that there exists a large variation among the assessed clones, which is higher in Eucalyptus grandis. The production of dry mass, associated to the estimation of mass of both lignin and charcoal proportionate a classification of the clones considered as the superior (clones number five, six and two), median (clones number ten, three, one and eight) and inferior (clones number nine, four and seven). Clone seven was the worsen for the charcoal production due to its low growth rate. The classification of the clones based on both the wood chemical characteristics and charcoal yield was not satisfactory. The growth rate was fundamental for the clones classification, being recommendable to incorporate it in future assessment of wood quality. Eucalyptus grandis clones were superior to Eucalyptus saligna clones.
Paulo Fernando Trugilho,José Reinaldo Moreira da Silva,Fábio Akira Mori,José Tarcísio Lima
CERNE , 2005,
Abstract: Wood presents great variation in longitudinal, transversal, radial and tangential direction. The variation in the radialdirection is the most perceptible and important for wood uses. This research aimed at evaluating the influence of the wood radialsampling position in the charcoal quality of six Eucalyptus clones. For evaluating the experiment it was adopted the randomized designdisposed in split plot, where clone represented the effect of the plot and radial position the effect of the split. The results indicated thatthe clone effect was significant for charcoal and fixed carbon yield, apparent relative density and fixed carbon content. The effect ofradial position was significant for apparent relative density, volatile materials and fixed carbon content. The effect of clone x radialinteraction position was significant for charcoal yield, volatile materials and fixed carbon content. The significance of the interactionindicates that the clone effect depends on the levels of the effect of the radial position, evidencing dependence between the two factors.
Cláudia Lopes Selvati de Oliveira Mori,José Tarcísio Lima,Fábio Akira Mori,Paulo Fernando Trugilho
CERNE , 2005,
Abstract: Due to the importance of wood characterization and standardization, this research evaluated the variability of woodcolor inside and among Eucalyptus spp clones, as well as radially and longitudinally inside the trunk through the quantitativecolorimetric color determination of clones of Eucalyptus wood., using CIELAB 1976 system, , through chromatic coordinates L*, a*,b*, C* e h. Eleven clones of natural Eucalyptus clones hybrids, cultivated at the Northwest of Minas Gerais State, were used. Theresults showed that: all colorimetric parameters were statistically different among clones, and among radial position of samples; itwas possible to identify both clones and samples position along the ray, producing wood of different colours, but tending to yellowishand reddish tonalities.
Thermogravimetric analysis of eucalyptus clones as a subside for charcoal production  [PDF]
Rosimeire Cavalcante dos Santos,Angélica de Cássia Oliveira Carneiro,Paulo Fernando Trugilho,Lourival Marin Mendes
CERNE , 2012,
Abstract: In Brazil, the use of wood for energy generation has been related to the charcoal production, due to the existing demand for the product by the steelworks sector. The tree species used in its great majority, are of the genus Eucalyptus. Nevertheless, regarding the variations that occur in the wood quality of the above cited genus, it is necessary to study them, since that fact can bring about negative consequences in both the quality and yield of charcoal, which will reflect negatively on the operations of the iron and steel industries blast furnaces. The work investigated the quality of the wood from different genetic materials of eucalyptus for charcoal production by means of thermogravimetric analysis. In the study, the resistance to the thermal degradation of wood and the qualitative and quantitative features of charcoal were taken into consideration. It was found that the highest peaks of thermal degradation occurred in the range of temperature between 300 and 4000C, the genetic material was the one which presented the lowest loss of total mass and the three was the less stable, having those presented, respectively, higher and lower gravimetric yield in charcoal; all the tested genetic materials presented satisfactory gravimetric results both in yield and in quality.
Evaluation of Eucalyptus clones in different places seeking to the production of vegetal charcoal Avalia o de clones de Eucalyptus em diferentes locais visando à produ o de carv o vegetal
Thiago Andrade Neves,Thiago de Paula Protásio,Allan Motta Couto,Paulo Fernando Trugilho
Pesquisa Florestal Brasileira , 2011, DOI: 10.4336/2012.pfb.68.319
Abstract: This research aim to evaluate the wood and charcoal quality of three Eucalyptus clones planted at different places and to verify the existent functional relations between the basic density and the depth of penetration of the Pilodyn pin. Three Eucalyptus clones were evaluated and four trees were sample for each clone and place. It was determined the depth of penetration of a Pilodyn pin at 1.30 m of height of the soil (DBH), average basic density (DBm), the basic density at DBH, the calorific value, lignin, total extractive, ashes and holocellulose contents and elemental chemical analysis (C, H, N and O). The wood was carbonized and the charcoal produced was evaluated quantitatively and qualitatively. In the evaluation of the wood characteristics a completely randomized design disposed in a factorial scheme 3 x 2 was used. A linear model was adjusted between DBm and the depth of penetration of the Pilodyn pin. It was possible to conclude that the clones present potential to be used for energy. The charcoal produced may be used in siderurgy. The linear model adjusted between DBm and the penetration of the Pilodyn pin was satisfactory. doi: 10.4336/2011.pfb.31.68.319 Os objetivos desse trabalho foram avaliar a qualidade da madeira e do carv o vegetal de três clones de Eucalyptus plantados em diferentes locais e verificar a rela o funcional existente entre a densidade básica e a profundidade de penetra o do pino do Pilodyn. Foram avaliados três clones de Eucalyptus e amostradas quatro árvores por clone em cada local. Determinou-se a profundidade de penetra o de um pino de a o do Pilodyn a 1,30 m de altura do solo (DAP), a densidade básica média (DBm), a densidade básica no DAP, o poder calorífico superior e os teores de lignina, extrativos totais, cinzas, holocelulose e a análise química elementar (C, H, N e O). A madeira foi carbonizada e o carv o produzido foi avaliado quantitativamente e qualitativamente. Na avalia o das características da madeira, utilizou-se um DIC em um esquema fatorial 3 x 2. Foi ajustado um modelo linear entre a DBm e a profundidade de penetra o do pino do Pilodyn. Foi possível concluir que os clones apresentaram potencial para o uso energético. O carv o vegetal produzido pode ser utilizado na siderurgia. O modelo linear ajustado entre a DBm e a penetra o do pino do Pilodyn mostrou-se satisfatório. doi: 10.4336/2011.pfb.31.68.319
Celiana Kátia Pereira Lima,Fábio Akira Mori,Lourival Marin Mendes,Angélica de Cássia Oliveira Carneiro
CERNE , 2007,
Abstract: Wood is a heterogeneous and complex material made up from different elements distributed along the trunk in several proportions. Associated with hygroscopicity, they have an influence on wood processing, including bonding. Therefore the present study sought, not only through the anatomic characterization and measurement but also through the total extractive content in Eucalyptus clones wood, to find out the correlation between the quality and the bonding junctions. Pearson correlations were used, considering 39 and 26 clones in interaction with the urea- formaldehyde sticker. The anatomic characteristics, relative to frequency and size of conducting vessels, radial parenchyma and its total extractive content presented correlation with the evaluation of clone’s bonding quality as well as with the percentage of wood failure and glue-line shear.
Paulo Fernando Trugilho,José Tarcisio Lima,Fábio Akira Mori
CERNE , 2003,
Abstract: The analysis of canonical correlation measures the existence and the intensity of the association between two groups of variables. The research objectified to evaluate thecanonical correlation between chemical and physical characteristics and fiber dimensional ofwood of Eucalyptus grandis and Eucalyptus saligna clones, verifying the interdependenceamong the groups of studied variables. The analysis indicated that the canonical correlationswere high and that in two cases the first and second pair were significant at the level of 1% ofprobability. The analysis of canonical correlation showed that the groups are notindependent. The intergroup associations indicated that the wood of high insoluble lignin contentand low ash content is associated with the high radial and tangential contraction and highbasic density wood.
Utilization potential of wood clones of Eucalyptus urophylla in the production of wood-cement panels  [PDF]
Lourival Marin Mendes,Fernanda Alvarenga Pomarico Loschi,Luana Elis de Ramos e Paula,Rafael Farinassi Mendes
CERNE , 2011,
Abstract: The objective of this study was to evaluate the potential of using clones of Eucalyptus urophylla in the production of wood-cement panels. The study used six clones of Eucalyptus urophylla with 8 years of age, from the Companhia Mineira de Metais, located in Paracatu - MG. For the formation of the panels it was used Portland cement CP V - ARI / Plus, possessing high initial resistance to mineral binder and calcium chloride (CaCl2) as accelerator for the cement curing. The panels were produced with the following parameters: dimensions of 49.5 x 49.5 x 1.5 cm, nominal density of 1.2 g/cm 3, relation wood: cement (1:2.5) and relation water: cement (1:1.5). The results can showed that: (1) for thickness swelling in two and twenty-four hours, only clones 19.28 and 58 attended the specifications, (2) for water absorption, clone 62 showed the best results, (3) to internal bond, only clone 58 didn`t attend specifications, (4) for the compression, clones 19.36 and 58 showed the best results, (5) for MOE and MOR, none of the clones presented values compatible to the bison process. It is suggested the continuation of this line of research, including the manipulation of variables of production, so that all properties be compatible to the minimum required standards.
Characterization of lipophilic wood extractives from clones of Eucalyptus urograndis cultivate in Brazil  [cached]
Siverio, F. O.,Barbosa, L. C. A.,Maltha, C. R. A.,Silvestre, A. J. D.
BioResources , 2007,
Abstract: The chemical compositions of the lipophilic extractives from four clones of Eucalyptus urograndis cultivated in Brazil were studied by gas chromatography-mass spectrometry (GC-MS) before and after alkaline hydrolysis. The four E. urograndis clones showed similar amounts of dichloromethane soluble (lipophilic) extractives (0.38-0.55% w/w). The major groups of compounds identified in the lipophilic fraction of extractives consisted mainly of fatty acids (mainly palmitic linoleic and oleic acids and small amounts of - and -hydroxyacids), steroids (mainly -sitosterol, -sitostanol), followed by minor amounts long chain aliphatic alcohols, hydrocarbons and aromatic compounds. The relative abundances of these groups were similar for three of the clones with exception of the clone Ugc, which was shown to have much higher amounts of fatty acids and sterols. The high amounts of extractives found in these clones, and particularly of Ugc, when compared with other Eucalyptus species, suggests an increased risk of pitch formation during bleached pulp production.
Cláudio Roberto Thiersch,José Roberto Soares Scolforo,Ant?nio Donizette de Oliveira,Gabriel Dehon Sampaio Pe?anha Rezende
CERNE , 2006,
Abstract: This study aimed at identifying at what point in the stem, in the longitudinal and cardinal direction, the pylodin penetration depth should be measured, for determining wood basic density, envisaging forestry inventory Data base used in compassed 36 parcels of 400 m2. Around the parcels 216 trees were sealed. Two clones (hybrid of E. grandis and E. urophylla), at the ages of 3; 4, 5 and 6 years, belonging to three different sites in East Brazil, encompassing East and Northeast of Espirito Santo state and south of Bahia state. In each measuring height of diameters it was also measured the penetration depth of the pylodin (in mm). The average basic density of scaled trees, was determined, departing from the cheaps, using the immersion method. The main conclusions were: The density equation, as function of the pylodin measures, age, site, diameters at 1.3m of ground and total height, was more precise, exact and stable than the density equation as function of pylodin, age, site and diameter, which in turn was more exact and stable than the density equation, as function of pylodin measures, age, site, diameter at a 1.3m of the ground and of total height, was precise and exact for all ages and sites, in dependent on if the pylodin measurements were taken in the South or in North fares, or in the average position between them. The height for measurement with pylodin can also be taken in the more ergonomic position of 1.3m. The density estimation, as a function of the measures with the pylodin, or as a function of the use of the pylodin, age, average dominant tree height an diameter at 1.3m of the ground, for both clones, was more precise when the measure with the pylodin was taken at the North face. The average tree basic density must always be taken by a specific equation for each clone, given that these equations differ statistically.
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