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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.
51

Genetic variation in wood properties of Pinus caribaea from Fiji

Nuevo, C. C. January 1982 (has links)
No description available.
52

Emprego da madeira do gênero Pinus na construção de estruturas de cobertura / Using Pinus timber in construction roof structures

Pinheiro, Roberto Vasconcelos 12 November 1996 (has links)
A redução e escassez das matas nativas nas regiões Sul/Sudeste se deu principalmente em virtude da contínua e descontrolada exploração das mesmas. Em vista disto e do incentivo fiscal, houve o aparecimento de grandes áreas de reflorestamento. Diante das circunstâncias, tomaram-se algumas espécies de Pinus como fonte alternativa para a obtenção de peças estruturais de madeira, com a recomendação do tratamento adequado para a preservação e classificação. O trabalho em questão tem como objetivo principal evidenciar a viabilidade técnica do emprego da madeira de Pinus na construção de estruturas treliçadas para cobertura. Como produto final da pesquisa, determinou-se também o consumo de madeira por metro quadrado de área coberta e o consumo de dispositivos de ligação. A utilização da madeira serrada de Pinus na construção civil, uma vez demonstrada sua viabilidade técnica, deverá se constituir em importante alternativa, considerando a implantação, a exploração e a possibilidade de manejo sustentados destas florestas artificiais, mantendo equilibrada a capacidade de oferta que, aliada à proximidade dos grandes centros consumidores, conduz a um custo final mais acessível. Finalmente, a plena utilização das florestas artificiais promove a desejada diminuição da pressão sobre as florestas nativas brasileiras. / The reduction and shortage of natives forests in south and south-east regions in Brasil happened specially because their continuous and incontrolled exploration. This fact and the governamental incentives provided large areas of planted forest. So, several Pinus species were taken as alternatives source for obtaining wooden structural pieces previously classified and preserved against biological attack. This work aims to demonstrate the technical viability of using Pinus timber in trussed roof structures. As final conclusion of the work, comparative tables related to wood comsuption per unit covered area and the joints comsuption are presented. The utilization of Pinus lumber in civil construction, demonstrated its technical and viability, will constitute an expressive alternative, taking in account the implantation, the exploration of these planted forest. So, it will keep equilibrated the wood deal that, in addition to the short distance related to the consumer centers, will conduct to a accessible final cost. At last, the full utilization of the planted forest permits desinable reduction of the extensive exploration of the brazilian native forests.
53

Critérios para classificação visual de peças estruturais de Pinus sp / Rules for visual grading of structural lumber of Pinus Sp

Carreira, Marcelo Rodrigo 22 April 2003 (has links)
A utilização estrutural da madeira serrada oriunda de florestas plantadas apresenta, no Brasil, um considerável potencial para expansão, pois as restrições sobre as florestas nativas são irreversíveis e o mercado se volta, em larga escala, para o uso das madeiras de reflorestamento, destacando-se o Pinus Sp como uma das espécies mais promissoras. Entretanto, como resultado do crescimento acelerado, a madeira proveniente destas espécies apresenta muitos defeitos, tornando-se imprescindível a realização da classificação para sua aplicação estrutural. Por outro lado, atualmente no Brasil não há procedimentos normatizados para a classificação de peças estruturais de madeira. Neste trabalho foi verificada a adequabilidade das regras de classificação visual do Southern Pine Inspection Bureau (SPIB) aplicadas à madeira de Pinus provenientes de florestas plantadas na região de Lages, Santa Catarina. Foi realizada a classificação visual de 600 peças de Pinus Sp. que tiveram a sua rigidez à flexão em relação ao eixo de menor inércia determinada por três métodos: ensaio estático de flexão, equipamento MSR, e equipamento de vibração transversal. Parte destas peças (96) distribuídas em igual número em quatro classes de resistência foi testada à flexão estática em relação ao eixo de maior inércia, com a finalidade de determinar a resistência e a rigidez à flexão de cada classe. O trabalho apresenta correlações entre propriedades de resistência, rigidez e a densidade. O método de classificação visual descrito nas regras do SPIB mostrou-se adequado para ser aplicado na madeira proveniente de florestas de Pinus Sp plantadas no Brasil. / The structural use of lumber from planted forests presents, in Brazil, a considerable potential for expansion, whereas the restrictions on the native forests are irreversible and the market turns, in wide scale, for the use of the reforestation lumber, standing out the lumber of Pinus Sp as one of the most promising species. However, as a result of the fast growth, the coming lumber of these species presents many defects, becoming indispensable the accomplishment of the grading for its structural application. On the other hand, now in Brazil there are not established procedures for the grading of structural lumber. In this work the adequability of Southern Pine Inspection Bureau (SPIB) grading rules applied to lumber of reforestation from city of Lages – SC, were verified. The visual grading of 600 pieces of Pinus Sp was accomplished. The flatwise bending stiffness was determined by three methods: static bending, MSR equipment, and equipment of transverse vibration. A part of these pieces (96) distributed in the same number in four structural grades it was tested to the static edgewise bending, with the purpose of determining bending strength and stiffness of each grade. This work presents correlations among strength properties, stiffness and the density. The method of visual grading described in the rules of SPIB was shown appropriate to be applied in the lumber from forests of Pinus Sp planted in Brazil.
54

The physiology of pinus patula seedlings in response to water stress and the implications for plantation regeneration in South Africa.

Rolando, Carol Ann. January 2008 (has links)
Pinus patula Schiede ex Schlect. & Cham. is the most widely planted softwood species for both pulpwood and saw timber in the South African forestry industry. High mortality of this species, often in excess of 20%, following planting is currently of major concern and has the potential to limit future deployment for commercial timber. Water stress is often reported to be a cause of mortality during regeneration in commercial forestry plantations yet, prior to 2007, there was no published research on the water relations of P. patula during regeneration in South Africa. This, together with questions raised by the industry as to the role of using water in the planting operation, initiated the series of studies conducted for this thesis. Water planting (application of water into the planting hole at the time of planting) of P. patula seedlings has been used commercially to reduce post-planting water stress and buffer against potentially extreme weather conditions immediately after planting. However, the primary role of the water, as well as its success in increasing survival following planting, has never been critically assessed. Since the use of water in the planting operation is expensive, it was essential that the benefits to using water were quantified, in terms of survival and growth, and justified, in terms of any monetary investment. In addition, there was a lack of local studies investigating the physiological characteristics of P. patula seedlings, particularly their tolerance to low soil water availability. To understand the role of water during the regeneration of P. patula in terms of plantation management and seedling physiology, a variety of research methodologies were used that included: applied field trials, multivariate methods (a retrospective investigation), pot trials and the development of a simple financial model. Four field trials were implemented to test the response in P. patula survival to water applied at planting. Two trials each were situated in the KwaZulu-Natal (KZN) Midlands and Mpumalanga Escarpment. The first trial at each site was planted in spring (October) and the second in summer (February). Watering treatments consisted of different quantities of water used in the planting operation and included 0.5 litres, 2 litres, 4 litres and no water (dry plant). Only at the spring planted trial in the KZN Midlands was survival of the dry planted seedlings significantly lower than that of the seedlings planted with water, at 90 days after planting. This may have been due to low rainfall during the week before and two weeks after planting, or the small size of the seedlings used in the trial. Application of 0.5 litres of water to the planting pit was sufficient to increase survival to a level equivalent to that where 2 or 4 litres of water was used, yet only increased soil moisture in the area immediately surrounding the seedling. This suggested that the role of the water applied during planting was increased root to soil contact. Overall, these four trials indicated that planting with water had the potential to increase survival only when soil water availability was low and rainfall sporadic. There was no effect of water applied at planting on early tree growth. While the results of the four field trials provided an indication of the effect of planting with water on subsequent survival of P. patula seedlings, there was concern that the results of the four trials may not be a true reflection of a dynamic situation. Survival in response to water applied at planting may vary from year to year and across forestry regions due to the unpredictable nature of rainfall and high air temperatures during the planting season, as well as the wide range of forestry sites across which P. patula seedlings are planted. To improve our understanding, a database of 58 trials was compiled where water and dry planting had been carried out. In this way it was possible to investigate whether the results from the four field trials were reflected in a range of previously conducted field trials implemented across time and space. The trials incorporated into the dataset were all planted to P. patula between 1990 and 2005 in the summer rainfall region of southern Africa. Data related to the climate, local weather, physiography and site management at each trial were also included. Summary statistics, linear correlation and multiple regression were used to determine if site-associated variables were related to an increase in survival in the water relative to the dry planted treatments. The analyses indicated that for all 58 trials, survival was lowest during the summer months, regardless of planting treatment. Planting with water was most likely to increase survival when used during spring, autumn and winter planting, although (as with the four applied field trials) there was no overall significant relationship between water planting and survival. Based on these results it was anticipated that an understanding of the water stress physiology of P. patula seedlings was required to explain the observed trends from a more fundamental perspective; if planting with water did not always increase survival, why not? Three pot trials were conducted to increase the understanding of the water relations of P. patula seedlings. These trials were also used to provide benchmark physiological data related to stressed (water) and unstressed seedlings. The first pot trial highlighted the importance of root plug moisture at the time of planting for increasing subsequent survival. The subsequent two pot trials were aimed at investigating the interaction between planting stock quality (as determined by measures of size) and soil water availability and the effect on survival, growth and physiology of P. patula seedlings. These results indicated that P. patula seedlings were not as sensitive to high air and soil temperatures (above 30°C) and low soil water availability (below -1.5 MPa) as previously thought. The seedlings were able to tolerate low soil water availability for several weeks and, following rewatering, were able to recover from moderate and severe water stress (a shoot water potential of below -1.5 MPa). This data supported the results from the four applied field trials and retrospective study of 58 trials, where the application of water to the seedlings at planting did not substantially increase survival. In the pot trials, stomatal conductance started to decrease when shoot water potential approached -0.8 to -0.9 MPa. Stomatal closure occurred at a shoot water potential between -1.2 MPa to -1.5 MPa. Mortality due to water stress occurred only in response to extended periods of low soil water and was associated with a shoot water potential of below -3.0 MPa. There was variability between seedlings in their potential for survival and growth. Inherently bigger seedlings had a greater capacity for new root growth following planting. New root growth, as well as a greater mass of new roots, was associated with higher shoot water potentials and higher rates of transpiration under conditions of low soil water availability. This indicated that seedling quality, as determined by size, may play a role in sensitivity to water stress. The field trials, retrospective study and pot trials indicated that the practice of planting with water was not always critical to the survival of P. patula seedlings. A simple financial model was developed to estimate whether planting with water represented a cost that could be used as a decision criterion, given certain growth parameters and management scenarios. The data projected by the model were also compared to actual research data for water versus dry planting (and the inclusion of an insecticide in the water). While these comparisons were specific to the parameters included in the model for this study, as well as the results of the research trials used in the benchmarking exercises, the model indicated that; 1) costs for planting with water were likely to be recovered only when no blanking (replacing of dead trees) was carried out, with capital invested at a low return rate (3%), 2) including an insecticide in the water increased the likelihood of cost recovery, and 3) site quality had an impact on the increase in survival required to recover planting method costs, with a greater percentage increase in survival required on lower quality sites. Lower quality sites often have a lower mean annual precipitation (associated with higher rainfall variability), or shallow soils (associated with lower soil water availability) and therefore are also likely to be sites where foresters may want to use water to reduce (drought related) mortality. The impact of site quality is thus also an important factor to include in any decisions regarding planting methods (i.e. using water) and their costs. Further investigations should be aimed at examining; 1) the interaction of root plug size (as determined by container type) and soil water availability on growth and physiology of P. patula seedlings, 2) the methods of grading seedlings within a population to select those that have a high potential for survival and growth, and 3) the effects of soil water availability on the physiology, survival and growth of P. patula cuttings, as well as other pine species and hybrids grown in South Africa, such as P. elliottii, P. elliottii x P. caribaea and P. patula x P. tecunumanii. It is likely that the proportion of forestry regions planted to these hybrids will increase in the future. / Thesis (Ph.D.)-University of KwaZulu-Natal, 2008.
55

Provenance variation in wood characteristics of Pinus caribaea Morelet and P. oocarpa Scheide

Wright, Jeffery Alan January 1987 (has links)
Densitometric, volumetric and paper-making traits of provenances of Pinus caribaea Morelet, P. oocarpa Schiede and P. patula SchiedeariclDeppe ssp. tecunumanii (Eguiluz and Perry) Styles were evaluated. Provenance mean values of densitometric density (DEN) and within tree density variation (VAR) were significantly different (p<0.05) at seven of the fourteen P.caribaea and at one of the seven of P. oocarpa and P. patula ssp. tecunumanii trials. Provenance mean valuesor volume under bark (VUB)and dry matter index (DMI) were significantly (p<0.05) different at all of the P. caribaea and at five of the P. oocarpa and P. patula ssp. tecunumanii trials. The inland provenances of P. caribaea were generally Higher for DEN and VAR than the coastal provenances, he Camelias, Mountain Pine Ridge, Rafael and Yucul provenances of P. patula ssp. tecunumanii were superior to P. oocarpa provenances for VUB and DMI in all of these trials and were superior to P. caribaea at two sites where the species were growing under similar conditions. Evaluation of densitometric races revealed large differences between species, provenances and sites for the width and density of latewood; this could explain much of the variation in VAR between these sources. The analysis of variance was used to assess genotype by environment interaction of DEN and VAR from eleven provenances of P. caribaea var. hondurensis Barrett and Golfari at eleven sites and from five provenances of P. oocarpa and four provenances of P. patula ssp. tecunumanii at sfx sites. Sites and provenances were significantly different for DEN and VAR in both series of trials out the site by provenance term was not statistically significant in either. Indications were that P. caribaea would be expected to have lower values of DEN and VAR at higher altitude. Provenances of P. oocarpa and P. patula ssp. tecunumanii were lower for VAR at sites of lower latitude but there were no individual site factors which could be correlated with DEN in these provenances. The comparison of full-scale pulping with micropulping of small wood samples from felled trees of six pine species in the Eastern Transvaal, South Africa, revealed positive and significant correlations for the pulp yield and paper strength traits. The correlation of tear index and VAR in these trees was positive and significant. Evaluation and analyses of a number of pine species and provenances by micropulping of cores from standing trees revealed significant differences for certain of the paper strength traits. The Caftas provenance of P. oocarpa was unusual in having high values for both tear index and burst index when grown in Zululand. Similar conclusions were reached for provenances of P. patula ssp. tecunumanii grown in the Eastern Transvaal. The conclusions of this thesis were: 1. Site climatic factors did not affect DEN and VAR of the different species and provenances in the same way; 2. The VAR term varied as a result of site, species and provenance; 3. There was no genotype by environment interaction for DEN«*rJ VAR; 4. The correlation of VAR with pulp and paper-making traits indicated that trees with high VAR were superior for tear index to trees with low VAR; 5. Micropulping of small wood samples could be used to assess the paper-making traits of individual trees.
56

Properties and distortion of Douglas-fir with comparison to radiata pine : a thesis submitted in partial fulfilment of the requirement for the degree of Masters [i.e. Master] of Engineering in Chemical and Process Engineering, University of Canterbury /

Wang, Eric Yunxin. January 2009 (has links)
Thesis (M.E.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (p. 117-125). Also available via the World Wide Web.
57

Pinheiros no Cerrado : estrutura das populações invasoras e efeitos da ocupação sobre nutrientes e microbiota do solo

Braga, Emilia Pinto 11 December 2015 (has links)
Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Ecologia, 2015. / Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2016-05-11T20:30:02Z No. of bitstreams: 1 2015_EmiliaPintoBraga.pdf: 2282932 bytes, checksum: 03552fd7e8030d7d5c0c98f65e9bb5d7 (MD5) / Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2016-12-20T12:24:53Z (GMT) No. of bitstreams: 1 2015_EmiliaPintoBraga.pdf: 2282932 bytes, checksum: 03552fd7e8030d7d5c0c98f65e9bb5d7 (MD5) / Made available in DSpace on 2016-12-20T12:24:53Z (GMT). No. of bitstreams: 1 2015_EmiliaPintoBraga.pdf: 2282932 bytes, checksum: 03552fd7e8030d7d5c0c98f65e9bb5d7 (MD5) / Os objetivos foram descrever as estruturas das populações invasoras de Pinus caribaea e Pinus oocarpa, avaliar impactos sobre os nutrientes do solo e de serapilheira e na diversidade funcional do solo e propor manejo para controle e exclusão. No JBB foram realizados dois levantamentos para descrever as populações e montar uma matriz de transição dos estágios de vida de cada população. Para P.caribaea foram definidos 7 estágios de vida: P, J1, J2,J3,J4,I e A;P. oocarpa teve 8 estágios, 7 iguais aos de P. caribaea e mais T. O manejo simulou a exclusão dos indivíduos das classes com maiores valores de sensibilidade. Amostras de serapilheira e de solos foram coletados para quantificar nutrientes e perfil fisiológico. Em 2013, a população amostrada de P caribaea possuiu 208 indivíduos, aumentando para 233 em um ano (λ=1,09). P.oocarpa teve uma população amostrada de 834 indivíduos em 2013, indo para 890 em 2014 (λ=1,07). A simulação das matrizes resultou em populações de 82.570 indivíduos deP.caribaea e 220.478 de P.oocarpaem 22 anos. Com manejo de exclusão de Imaturos e Adultos, as populações de P.caribaea e P.oocarpa teriam, respectivamente, 2.117 e 12.482 indivíduos. Pinheiros adensaram o dossel e produziram mais serapilheira que Cerrado, mas não afetou a qualidade nutricional da serapilheira nem nos nutrientes do solo. Não foi observada relação entre nutrientes de serapilheira e de solo com a comunidade bacteriana. Não houve influência da presença de pinheirosno perfil fisiológico do solo. O perfil fisiológico mudou sob influência do regime pluviométrico. Este é o primeiro relato da invasão das espécies P. caribaea e P. oocarpa e seus efeitos, e também são inéditas as propostas e projeções de manejo para o JBB das duas espécies invasoras estudadas. / The objectives of this study were to: describe the population structure of these species, evaluate their impacts on litter and soil nutrients, evaluate their impacts on the functional diversity in the soil and 4) propose a solution for control and exclusion of these species over time. To study the populations, two surveys were done to provide data for a transition matrix for each species. For P.caribaea the following life stages were defined: P, J1, J2, J3, J4, I, A. For P.oocarpa another stage was included: T. A management proposal for these species was made based on the transitions with the highest values of sensitivity. In 2013, the P. caribaea population in the transects had 208 individuals and this increased to 233 in after one year (λ=1,09). The initial population size of P. oocarpa was 834 and this increased to 890 iin 2014 (λ=1,07). The projection of population growth over a 22 year period indicated an increase in the total number of individuals to 82,570 for P. caribaea and to 220,478 for P. oocarpa. However, if all adult individuals of each species were actively removed, the final estimate for population sizes of each species was 2,117 and 12,482 individuals, respectively. The presence of pine species resulted in greater crown closure and a higher quantity of litter on the soil surface comparing sites with and without pines, but there was no difference in the nutrient content of the litter and in soil. There was no relation between nutrient concentration in the litter and soil and the soil bacterial community. A difference in the preference of carbon sources between the rainy and dry season was observed. This is the first report of invasion of these pine species in the Cerrado, their effects, and also of proposals for their management in the JBB.
58

Influencia do espaçamento sobre a qualidade e o rendimento da madeira serrada de Pinus taeda L.

Chies, Daniel 19 June 2013 (has links)
Foram confeccionadas chapas de partículas que se caracterizaram pelo uso de partículas com espessura e comprimento controlados, maiores que aquelas usadas nas chapas convencionais. A matéria-prima foi proveniente de três espécies de Pinus, isto é, P. taeda, P. elliottii e P. patula, com 17 anos respectivamente. As chapas, num total de 30 para cada espécie, foram prensadas a quente, com temperatura de 160°C e pressão de 35 kg/cm². As densidades nominais foram de 0,60 e 0,75 g/cm³ para chapas com 1,3 cm de espessura. A resina usada foi fenol-formaldeido (FF) em dois níveis, 4 e 8 porcento (peso/peso). As chapas foram avaliadas pelos seguintes testes: Flexão estática (Módulo de Ruptura (MOR) e Módulo de Elasticidade (MOE)), Estabilidade Dimensional (Expansão Linear (EL), Inchamento em Espessura (IE e Absorção de Água (AA), Ligação Interna (LI) e Resistência ao Arrancamento de Parafuso (RAP) Os valores mínimos e máximos obtidos, considerando-se as três espécies, foram os seguintes: MOR = 245,16 e 550,18 kg/cm², MOE 52017 e 105503 kg/cm² EL = 0,036 e 0,109%; IE (2hs) 23,09 e 59,41% (24hs) 30,16 e 65,33%; AA (2hs) 34,73 e 112,49%, (24hs) 49,18 e 122,07%; LI = 9,32 e 24,49 kg/cm² e RAP = 130,2 e 269,8 kg. Esses resultados obtidos foram considerados excelentes, uma vez que corresponderam e no raramente ultrapassaram os valores mínimos exigidos pela norma comercial CS 236-66, normalmente utilizados nos EUA para este tipo de chapa. Cabe uma ressalva para teste Inchamento em Espessura que primeira vista parece ser muito elevado, mas deve-se considerar que as condições foram bastante drásticas, isto é, imersão em água por 2 e 24 horas, sem nenhum 'tratamento superficial para proteção das chapas.
59

Viabilidade técnica e econômica da poda em plantações de Pinus Taeda e Pinus Elliottii

Cardoso, Denise Jeton 05 June 2013 (has links)
Brazil first began concerning about producing pine clearwood 30 years ago, even though it has been quite a common activity in other countries for several years. The wood originated from the first pruned pine plantations began to be harvested in recent years. However, the procedures used in the pruning operation vary from region to region, as well as the thinning regime and quality of the site, which directly affect the growth of the trees and the amount of knot-free wood produced at the end of the rotation. The expected price for this product is equal to or greater than 100% of the wood value for the same grade, without pruning. However, due to the increasing production of composition boards and other changes taking place in the market, clearwood prices have been decreasing, coming close to the prices of unpruned wood. One of the objectives of this study was to quantify the clearwood volumes effectively and potentially generated from pruned logs. Another objective was to establish the minimum price to be charged for the pruned wood so that the same economic result from an unpruned stand could be achieved, considering the costs of pruning and yield in commercial volume in each situation. Yet, the maximum price to be asked for was calculated in order to make it an advantage to buy pruned logs rather than buying clearwood veneer in the market. The cost of pruning only the first log and pruning the first two logs of each tree was considered. The data were taken from eight stands located in the regions of Jaguariaíva, Sengés and Ibaiti, all in Paraná State, and the region of Itapeva, in São Paulo State. The ages of the plantations range between 18 and 24 years old, seven stands being of Pinus taeda and one of Pinus elliottii. The log batches were processed in veneer companies located in Sengés and Ibaiti. The log processing was efficient, for it was possible to measure the diameter of the knotty core as the first knot was shown. The results show that on average 52.9 % of the volume of the batch from the first logs corresponds to the volume of potentially clearwood against 50.1 %, obtained in the batches containing second logs. However, 10.8 % of the volume of these logs was turned into clearwood veneer, whereas in the batches from unpruned stands, this percentage did not exceed 2.3 %. It was observed that the second log has a better shape than the first, both in pruned and unpruned batches, although the volume of the second log is smaller. The pruned trees have a better shape than the unpruned trees and they achieved, on average, 6.5 % more volume than the latter, for the same dbh (diameter at breast height) and height. Regarding the price, the pruned logs must have, in relation to the value of the same grade unpruned, a minimal additional of 53.9 %, so as the same economic result from an unpruned stand and a maximum additional of 77 % can be achieved, so that the buyer might prefer to purchase these logs instead of purchasing the veneers. It is recommended that pruning be performed only on the first log, preferably in very productive sites, due to the uncertainty about the demand for clearwood. Performing pruning on the second log is considered important to make up for the small amount of clearwood in stands of low and medium productivity.
60

Características morfológicas de celuloses branqueadas de pinus e eucalyptus em analisador óptico automático de fibras /

Menegazzo, Miguel Lara, 1985- January 2012 (has links)
Orientador: Cláudio Angeli Sansígolo / Banca: Elias Taylor Durgante Severo / Banca: Gustavo Ventorim / Resumo: Buscando alternativas para o aperfeiçoamento dos recursos florestais nas indústrias de celulose e papel, o presente trabalho teve como objetivo analisar as características morfológicas de celuloses branqueadas de Pinus e Eucalyptus em analisador óptico automático de fibras devido a grande importância nas características e propriedades do papel. Foram comparadas a morfologia de três amostras de celulose fofa ("fluff pulp") Kraft branqueada de fibra longa de mercado procedente dos Estados Unidos e duas amostras de celulose branqueadas do híbrido de E urophylla x E. grandis, sendo uma amostra obtida de clone de menor densidade básica da madeira, e a outra amostra de clone de maior densidade básica da madeira, utilizando o analisador óptico de fibras Kajaani FS-200. Em seguida foram comparadas as diferenças de morfologia de fibras entre celuloses branqueadas de fibra longa (Pinus) e fibra curta (E. urophylla x E. grandis). Utilizando equipamento Kajaani FS-300, foi analisada a influência do refino (0, 15 e 30 minutos) em amostras de celulose branqueadas integral e classificada em equipamento Bauer McNett de E. globulus em relação à morfologia de fibras e propriedades de resistências físico-mecânicas da celulose. Nas amostras de celulose branqueada de Pinus, houve uma variação nos valores das dimensões em relação comprimento, espessura da parede e diâmetro do lume; a largura foi à dimensão mais estável. Obteve-se relação positiva entre espessura da parede, fração parede e "coarseness", e relação negativa destes parâmetros com o índice de curvatura da fibra. O comprimento da fibra relacionou positivamente com a espessura da parede, índice de enfeltramento e "coarseness", e negativamente com o... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Seeking alternatives for the improvement of forest resources in the industries of pulp and paper, this study aimed to analyze the morphological characteristics of bleached pulps from Pinus and Eucalyptus in analyzer automatic optical fiber due to the great importance of the characteristics and properties of paper. Compared the morphology of three samples of pulp fluff bleached softwood kraft market from the United States and two samples of bleached pulp and the hybrid E. urophylla x grandis, and a sample obtained from clone lower basic density, and another sample of clone high basic density of wood, using the analyzer optical fiber Kajaani FS-200. Following the differences were compared in morphology of pulp fibers from bleached softwood (pine) and hardwood (E. urophylla x E. grandis). Using equipment Kajaani FS-300, we analyzed the effect of beating (0, 15 and 30 minutes) in full samples of bleached pulp and classified pulp in equipment Bauer McNett of the E. globulus in relation to morphology and properties of pulp physical and mechanical resistance. Samples of pine pulp bleached, there was a variation in the values of the dimensions in relation length, wall thickness and lumen diameter, the width of the scale was more stable. Positive relation was obtained between wall thickness, wall fraction and coarseness, and negative relationship of these parameters with the index of curvature of the fiber. The fiber length correlated positively with the thickness of the wall, felting index and "coarseness", and negatively associated with lumen diameter and fiber population. The dimensions of fibers varied in two samples of Eucalyptus pulp from wood of different densities basic. The pulp fibers in wood from the lower basic density showed... (Complete abstract click electronic access below) / Mestre

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