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Wood density and fibre morphology of Pinus caribaea var. hondurensis Barrett and Golfari from Fiji were studied in relation to pulp properties. Densitometry and anatomical measurement were examined using billets taken from a sub-sample of 20 12-13 year old trees, chosen as representative of the density range observed in a first sample of 120 trees. Pulping properties were examined at the Tropical Products Institute, London. Considerable differences between trees were found in all characteristics examined and all characteristics showed fairly marked tree to tree variation in development patterns in a radial direction though differences along the stem were small. Between ring differences for ring width, density, cell wall thickness and cell wall percentage were considerable but cell lumen width and cell diameter were fairly constant between rings. Tree morphological characteristics cannot be used for estimation of whole tree values for any of the features studied. Whole tree values for wood characteristics can be accurately predicted from samples taken at 5% height level. Characteristic patterns of wood density distribution classes and tracheid cross sectional dimension classes were found, resembling chi-squared, binomial and bimodal curves. Wood properties could be used to predict pulp yield percentage and tear factor accurately by simple regression, less precise estimates could be obtained in this way, for burst factor and breaking length, which were best indicated by cell wall thickness. The best indicators of variation in pulp total yield percentage were chemical properties. Density was the best indicator of tear factor whilst cell wall thickness was the most important factor in explaining burst factor and breaking length. Growth rate showed negative correlation with wood density; trees of lower density produce paper of a strength generally at least equal to that obtained with higher density trees, though tear factor was lower. Thus the selection of trees for fast growth rate is suggested as the most profitable course. The most desirable selection criteria are listed.

These (Ph. D.)--University of Queensland, 2001. / Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin-Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 132-136).

Made available in DSpace on 2014-06-11T19:31:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-12-15Bitstream added on 2014-06-13T19:42:05Z : No. of bitstreams: 1 aroni_as_dr_botfca.pdf: 7843042 bytes, checksum: 8ed479d2ab8480a3b560315182072192 (MD5) / Os principais objetivos são: a) Estudar as variações das densidades da madeira no sentido radial e longitudinal, utilizando a técnica de Atenuação da Radiação Gama do Amerício-241 e a técnica de Imersão; b) Avaliar a densidade média ponderada por árvore e por tratamento e, para isso, utilizará as espécies Seminal de Pinus caribaea var.hondurensise espécie híbrida de Pinus caribaea var.hondurensis x Pinus tecunumannii; c) Avaliar os índices de produtividade pelos Incrementos Médios Anuais de Volume (IMAV), Incrementos Médios Anuais de Massa (IMAM) e Incrementos Médios Anuais de Energia (IMAE) de cada tratamento, correlacionando-os com seus respectivos valores de densidade; d) Determinar o poder calorífico superior de cada tratamento pelo método da Bomba calorimétrica; e) Comparar os métodos Atenuação da radiação Gama do Amerício-241 e o de Imersão. Para o estudo foram selecionadas 45 árvores da empresa DURATEX S/A., na região de Agudos-SP., entre as espécies Seminal Pinus caribaea var.hondurensis e ahíbrida Pinus caribaea var.hondurensis x Pinus tecunumannii. Foram selecionados cinco tratamentos do híbrido de Pinus caribaea var.hondurensis x Pinus tecunumannii que mais se destacaram dentre os 12 híbridos existentes no povoamento, sendo denominados como 'H IND. 1', 'H IND. 2', 'H IND. 3', 'H IND. 4', 'H IND. 5' e um tratatamento de material Seminal do Pinus caribaea var.hondurensis, sendo denominado como S, espécie tropical de gênero Pinus proveniente de um ensaio vizinho equiâneo submetido às mesmas condições edafo-climáticas e submetido aos mesmo tratos culturais na implantação. A técnica de atenuação permite observar esses detalhes, o que não poderia ser feito com as técnicas tradicionais. Algumas árvores tiveram um comportamento mais uniforme para a densidade, demonstrando uma menor sensibilidade aos fatores climáticos... / The main objectives are: a) To study wood desity variations inthe radial and longidutinal directions, using the Americium-241 Gamma Radiation Attenuation technique and the immersion technique; b) To evaluate the average density mesaured per tree and per treatment and, for this, the Seminal species of Pinus caribaea var.hondurensis and the hybrid species of Pinus caribaea var.hondurensis x Pinus tecunumannii will be used; c) To evaluate the yield rates based on the Annual Average Volume Increments (AAVI), the Annual Average Mass Increments (AAMI) and the Annual Average Energy Increment (AAEI) of each treatment, correlating them to their respective density values; d) To determine the superior calorific power of each treatment by means of the calorimetric Bomb; e) To compare the Americium-241 Gamma Radiation Attenuation method and the Immersion method. For such study, 54 trees from the company DURATEX S/A were selected, in the region of Agudos-SP, among Seminal species of Pinus caribaea var.hondurensis and the hybird Pinus caribaea var.hondurensis x Pinus tecunumannii. Five treatments of the hybrid of Pinus caribaea var.hondurensis x Pinus tecunumannii were selected, which were the most important among the 12 ones which existed in the population, being named as 'H IND. 1', 'H IND. 2', 'H IND. 3', 'H IND. 4', 'H IND. 5' and a Seminal material treatment of Pinus caribaea var.hondurensis, beinh named as S, tropical species of the family Pinus coming from an equineous neighbor study which underwent the same edaphic-climatic conditions and which underwent the same cultural traits in their implantation. The attenuation technique allows the observation of such details, which could not be made with traditional techniques. Some trees had a more uniform behavior concerning density, demonstrating a lower sensitivity to climatic factors. The used methods for the basic wood density collection... (Complete abstract click electronic access below)

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Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-07-26T16:32:18Z No. of bitstreams: 1 2016 - Marcelly Alves da Silva.pdf: 1109436 bytes, checksum: cf0918f898aa3347f3dda630016df417 (MD5) / Made available in DSpace on 2016-07-26T16:32:18Z (GMT). No. of bitstreams: 1 2016 - Marcelly Alves da Silva.pdf: 1109436 bytes, checksum: cf0918f898aa3347f3dda630016df417 (MD5) Previous issue date: 2016-02-26 / SILVA, Marcelly Alves da. Using of calcium and magnesium lignosulfonate in mixtures with phenol-formaldehyde in particleboard manufacturing. 2016. 33 p. Dissertation (Master in forest and Environmental Sciences). Instituto de Florestas, Universidade Federal Rural do Rio de Janeiro, Serop?dica, RJ, 2016. The purpose of this study was to evaluate the feasibility of using calcium and magnesium lignosulfonate (LS) in the production of Pinus caribaea var. caribaea particleboard panels, used pure and in mixtures with phenol-formaldehyde (FF). It was determined the basic and apparent density of the wood, as well as the physical and chemical properties of adhesives. In order to evaluate the effect of FF replaced by LS on the physical and chemical properties, panels were produced with different concentrations of these adhesives. The experiment consisted of two phases. The first phase was performed under temperature of 160?C and pressing time of 10 mitutes with the following compositions: 100% FF, and LS substitutions in the proportions of 20, 40, 60, 80 and 100%, with three replications each. In the second phase, the first phase of the three treatments with lower performance in the mechanical properties were tested at a temperature of 180?C and to 7 minutes. The results of basic and apparent wood density were 0.54 and 0.60 g/cm?, respectively. In the second stage the temperature increased and decreased of the pressing time were not sufficient to consolidate the panel, becoming not possible to analyze the results of this phase. In respect to the thickness swelling and water absorption, increases in the proportion of lignosulfonate in the mixture also raise up these values. The substitution of the phenol-formaldehyde adhesive of lignosulfonate was satisfactory in attendance the specific norm for mechanical properties by 80%. The lignosulfonate showed efficiency in the use as an adhesive in the production of particleboard in mixtures with phenol formaldehyde, suggesting that this is an alternative of the use of synthetic adhesives. / SILVA, Marcelly Alves da. Utiliza??o de lignosulfonato de c?lcio e magn?sio em misturas com fenol-formalde?do na produ??o de pain?is aglomerados. 2016. 33 p. Disserta??o (Mestrado em Ci?ncias Ambientais e Florestais). Instituto de Florestas, Universidade Federal Rural do Rio de Janeiro, Serop?dica, RJ, 2016. O objetivo deste estudo foi avaliar a viabilidade da utiliza??o do lignosulfonato de c?lcio e magn?sio (LS) na produ??o de pain?is aglomerados de Pinus caribaea var. caribaea, na forma pura e em misturas com fenol-formalde?do (FF). Foram determinadas a densidade b?sica e aparente da madeira, bem como as propriedades f?sicas e qu?micas dos adesivos. De modo a avaliar o efeito da substitui??o de FF por LS sobre as propriedades f?sicas e qu?micas, foram produzidos pain?is com diferentes concentra??es desses adesivos. O delineamento experimental foi constitu?do de duas fases. A primeira fase foi realizada sob a temperatura de 160?C e tempo de prensagem de 10 minutos, com as seguintes composi??es: 100% de FF, e as substitui??es por LS nas propor??es de 20, 40, 60, 80 e 100%, com tr?s repeti??es cada. Na segunda fase, os tr?s tratamentos da primeira fase com desempenho inferior nas propriedades mec?nicas foram testados na temperatura de 180?C em tempos de prensagem de 5 e 7 minutos. Os resultados m?dios da densidade b?sica e aparente da madeira foram de 0,54 e 0,60g/cm?, respectivamente. Na segunda fase, o aumento da temperatura e a diminui??o do tempo de prensagem n?o foram suficientes para consolidar o painel, n?o sendo poss?vel analisar os resultados desta fase. Com rela??o ao inchamento em espessura e absor??o de ?gua, ? medida que aumentou a propor??o de lignosulfonato na mistura elevaram-se tamb?m esses valores. Em at? 80%, a substitui??o do adesivo fenol-formalde?do por lignosulfonato foi satisfat?ria no atendimento a NBR 14810-2 (ABNT,2013) para propriedades mec?nicas. O lignosulfonato apresentou efici?ncia na utiliza??o como adesivo na produ??o de pain?is aglomerados em misturas com fenol-formalde?do, evidenciando que esta ? uma alternativa ? utiliza??o de adesivos sint?ticos.

Orientador: Marcos Antonio de Rezende / Banca: Marcelo Agenor Pavan / Banca: Angelo Cataneo / Banca: Isabel Cristina Buttignon / Banca: João Alberto Borges de Araujo / Resumo: Os principais objetivos são: a) Estudar as variações das densidades da madeira no sentido radial e longitudinal, utilizando a técnica de Atenuação da Radiação Gama do Amerício-241 e a técnica de Imersão; b) Avaliar a densidade média ponderada por árvore e por tratamento e, para isso, utilizará as espécies Seminal de Pinus caribaea var.hondurensise espécie híbrida de Pinus caribaea var.hondurensis x Pinus tecunumannii; c) Avaliar os índices de produtividade pelos Incrementos Médios Anuais de Volume (IMAV), Incrementos Médios Anuais de Massa (IMAM) e Incrementos Médios Anuais de Energia (IMAE) de cada tratamento, correlacionando-os com seus respectivos valores de densidade; d) Determinar o poder calorífico superior de cada tratamento pelo método da Bomba calorimétrica; e) Comparar os métodos Atenuação da radiação Gama do Amerício-241 e o de Imersão. Para o estudo foram selecionadas 45 árvores da empresa DURATEX S/A., na região de Agudos-SP., entre as espécies Seminal Pinus caribaea var.hondurensis e ahíbrida Pinus caribaea var.hondurensis x Pinus tecunumannii. Foram selecionados cinco tratamentos do híbrido de Pinus caribaea var.hondurensis x Pinus tecunumannii que mais se destacaram dentre os 12 híbridos existentes no povoamento, sendo denominados como 'H IND. 1', 'H IND. 2', 'H IND. 3', 'H IND. 4', 'H IND. 5' e um tratatamento de material Seminal do Pinus caribaea var.hondurensis, sendo denominado como S, espécie tropical de gênero Pinus proveniente de um ensaio vizinho equiâneo submetido às mesmas condições edafo-climáticas e submetido aos mesmo tratos culturais na implantação. A técnica de atenuação permite observar esses detalhes, o que não poderia ser feito com as técnicas tradicionais. Algumas árvores tiveram um comportamento mais uniforme para a densidade, demonstrando uma menor sensibilidade aos fatores climáticos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The main objectives are: a) To study wood desity variations inthe radial and longidutinal directions, using the Americium-241 Gamma Radiation Attenuation technique and the immersion technique; b) To evaluate the average density mesaured per tree and per treatment and, for this, the Seminal species of Pinus caribaea var.hondurensis and the hybrid species of Pinus caribaea var.hondurensis x Pinus tecunumannii will be used; c) To evaluate the yield rates based on the Annual Average Volume Increments (AAVI), the Annual Average Mass Increments (AAMI) and the Annual Average Energy Increment (AAEI) of each treatment, correlating them to their respective density values; d) To determine the superior calorific power of each treatment by means of the calorimetric Bomb; e) To compare the Americium-241 Gamma Radiation Attenuation method and the Immersion method. For such study, 54 trees from the company DURATEX S/A were selected, in the region of Agudos-SP, among Seminal species of Pinus caribaea var.hondurensis and the hybird Pinus caribaea var.hondurensis x Pinus tecunumannii. Five treatments of the hybrid of Pinus caribaea var.hondurensis x Pinus tecunumannii were selected, which were the most important among the 12 ones which existed in the population, being named as 'H IND. 1', 'H IND. 2', 'H IND. 3', 'H IND. 4', 'H IND. 5' and a Seminal material treatment of Pinus caribaea var.hondurensis, beinh named as S, tropical species of the family Pinus coming from an equineous neighbor study which underwent the same edaphic-climatic conditions and which underwent the same cultural traits in their implantation. The attenuation technique allows the observation of such details, which could not be made with traditional techniques. Some trees had a more uniform behavior concerning density, demonstrating a lower sensitivity to climatic factors. The used methods for the basic wood density collection... (Complete abstract click electronic access below) / Doutor

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Programa Doctoral conjunto "Desarrollo Sostenible Conservativo de Bosques Tropicales: manejos Forestal y Turístico".