Abstract This work evaluated the influence of impregnation of boron compounds, in three concentrations, on Pinus sp. veneers, and its effect on the properties of plywood. The experiment was carried out in a completely randomized design, in a 3 × 3 + 1 factorial scheme, with three boron compounds (boric acid, borax, and disodium octaborate tetrahydrate) and three solution concentrations (1%, 3%, and 5%) plus the control. The panels were produced with three or five veneers, depending on the test, impregnated by dipping in boron compound solutions for 15 min and bonded with urea-formaldehyde adhesive. The apparent density, water absorption, thickness expansion, hygroscopicity, resistance to static bending (parallel and perpendicular to the grain) and shear strength were evaluted. All tests were carried out following the European Committee for Standardization, and the results were compared to the Brazilian Association of Mechanically Processed Wood requirements. Based on the results, it is recommended to use boric acid at a concentration of 1% or 3% or the other compounds tested at a concentration of 1%. sp veneers plywood design scheme borax tetrahydrate 1%, (1% 5% 5 control test ureaformaldehyde urea formaldehyde adhesive density absorption expansion hygroscopicity parallel grain evaluted Standardization requirements (1 (

Resumo Objetivou-se avaliar a influência da impregnação de compostos de boro, em três concentrações, em lâminas de Pinus sp., e seu efeito nas propriedades de compensados. O experimento foi realizado em delineamento inteiramente casualizado, em esquema fatorial 3 × 3 + 1, sendo três compostos de boro (ácido bórico, bórax e octaborato dissódico tetrahidratado) e três concentrações (1%, 3% e 5%) mais o controle. Os painéis foram produzidos com três ou cinco lâminas, encolados com uréia-formaldeído, com as lâminas impregnadas por imersão nas soluções de compostos de boro por 15 min. Foram avaliadas a densidade aparente, absorção de água, expansão de espessura, higroscopicidade, resistência à flexão estática (paralela e perpendicular à grã) e resistência ao cisalhamento. Todos os testes foram realizados de acordo com o Comitê Europeu de Padronização. Para o controle de qualidade, os resultados foram comparados com as exigências da Associação Brasileira de Madeira Processada Mecanicamente. Com base nos resultados, recomenda-se usar ácido bórico na concentração de 1% ou 3% ou os demais compostos testados na concentração de 1%. Objetivouse Objetivou se sp sp. compensados casualizado 1 tetrahidratado 1%, (1% 5% 5 uréiaformaldeído, uréiaformaldeído uréia formaldeído, formaldeído uréia-formaldeído min aparente água espessura higroscopicidade paralela grã cisalhamento Padronização qualidade Mecanicamente recomendase recomenda (1 (

Abstract: Thermal modification of wood is an environmentally friendly method to improve wood durability, mainly against microorganisms. By employing a process similar to the ThermoWood®, various Gmelina arborea (gamhar) wood specimens were thermally modified at 180 °C, 200 °C, and 220 °C for 3 hours. The effects of the thermal modification process on the resistance to decay by rot-fungi, and attack by subterranean, arboreal, and dry-wood termites were determined. Generally, the thermal modification improved the resistance of Gmelina arborea (gamhar) to decay by Trametes versicolor with increasing process temperature. However, the effect of the process was null on the resistance to biodeterioration by the brown-rot fungus Coniophora puteana and the dry-wood termites Cryptotermes brevis. Even so, the visual damage caused by Cryptotermes brevis was slight. Untreated and thermally modified woods recorded higher resistance to Coniophora puteana than Trametes versicolor. Mass loss caused by Nasutitermes corniger also decreased with increasing thermal modification temperature. According to the visual damage rating values, the attack by Nasutitermes corniger was slight. However, the thermal modification inversely impacted Gmelina arborea (gamhar) attack by Macrotermes sp., as its resistance in the field to the termites decreased with increasing modification temperature. Thus, the thermal modification process contributed to improving the decay resistance of the modified wood to white-rot fungus Trametes versicolor and attack by the arboreal termites Nasutitermes corniger exposed indoors. On the other hand, thermally modified Gmelina arborea (gamhar) wood was very susceptible to Macrotermes sp. in the field. This work would provide a reliable reference document to guide wood industry stakeholders in assessing the performance of untreated and thermally modified Gmelina arborea (gamhar) wood in situations exposed to fungi and termite species adopted.

Abstract The objective of this work was to evaluate the potential of native species used in ecological restoration in Brazil (Peltophorum dubium - canafístula, Hymenaea courbaril - jatobá, Jacaranda cuspidifolia - jacarandá, and Enterolobium contortisiliquum - timboril) as raw material for the supply of sawmills. Due to the difficulties in sampling trees of native species, four trees per species were collected, at age of 12 years, in a legal reserve area. The sampled trees were evaluated as being quite characteristic of trees of the same genetic material. The trees’ diameter was measured, the percentage of bark and the taper were measured, and the lumber yield of each species was calculated. The boards were air-dried. Based on the DBH, timboril had the greatest potential for biomass production, but its wood quality was unsatisfactory. To supply raw material for sawmills, in addition to jatobá, we suggest investing in plantations of canafístula and jacarandá. Peltophorum jatobá jacarandá sawmills collected 1 years area measured calculated airdried. airdried air dried. dried air-dried DBH production unsatisfactory

Abstract The use of tropical species in forest plantations is an alternative to supply the demand of good quality wood. However, information regarding the performance of planted tropical species is scarce. The aim of this study was to provide an assessment of the lumber potential of Cariniana legalis (“jequitibá-rosa”), Zeyheria tuberculosa (“ipê-felpudo”) and Cordia trichotoma (“louro-pardo”) in a forest plantation. Three trees per species were sampled at age of 50 months, planted in a mixed stand with 2 x 4 m spacing in Porto Seguro, Bahia, Brazil. We assessed characteristics of the trees, the logs, lumber yield, and partial volumetric shrinkage of wood. Total volumetric shrinkage of ipê-felpudo, jequitibá-rosa and louro-pardo would be around 12.80%, 13.40% and 11.58%, respectively. Among the three species analyzed, louro-pardo had the best performance, followed by ipê-felpudo, while jequitibá-rosa had the worst performance. All species had good performance regarding log quality and dimensional stability of wood.

Resumo As pesquisas brasileiras sobre o processo que tem sido denominado de retificação térmica, termorretificação, tratamento térmico, tratamento com calor e modificação térmica vêm crescendo desde o ano 2000. Como a padronização de conceitos é algo importante para o desenvolvimento científico de uma determinada área, o objetivo deste trabalho foi realizar uma revisão bibliográfica sobre esse processo com a finalidade de se propor a nomenclatura técnica mais adequada para o mesmo em Língua Portuguesa, com fins de padronização. Foram revisados os artigos publicados no tema em 2015, em dez revistas científicas internacionais e em sete brasileiras. Também foi verificado um livro didático estrangeiro, o maior evento científico do tema e informações de empresas europeias detentoras de patentes de processo e que comercializam produtos. Com base análise de todas as fontes, para a padronização do processo e da madeira processada/produto originado, recomenda-se o uso das nomenclaturas técnicas modificação térmica e modificada termicamente, respectivamente. Tecnicamente, não está errado o uso dos termos tratamento térmico e tratada termicamente e seus equivalentes tratamento com calor e tratada com calor (apesar destas serem formas mais raras). Contudo, para não incorrer em erros de interpretação, essas nomenclaturas devem ser evitadas porque são genéricas e tradicionalmente empregadas para o consagrado processo de secagem artificial da madeira. Não se estimula o uso das nomenclaturas retificação térmica e termorretificação, bem como seus derivados retificada termicamente e termorretificada.

Abstract Brazilian studies of a process that has been variously called in Portuguese retificação térmica, termorretificação (both with no English correspondent), tratamento térmico (thermal treatment), tratamento com calor (heat treatment) or modificação térmica (thermal modification) have been increasing since 2000. Because the standardization of concepts is important for the scientific development of any subject, the aim of this article was to provide a literature review about this process, to propose the most appropriate technical nomenclature for it in Portuguese, aiming at standardization. We reviewed articles about this process, published in 2015, in ten international scientific journals and seven Brazilian journals. We also verified a foreign textbook, the largest scientific event on the subject and information on European companies that have process patents and products on the market were also verified. Based on all the verified sources, it is recommended the technical nomenclature ‘modificação térmica’ (thermal modification) for the process and ‘modificada termicamente’ (thermally modified) for the wood/products. Technically, it is not wrong to use the terms ‘tratamento térmico’ (thermal treatment) and ‘tratada termicamente” (thermally treated) and their equivalents ‘tratamento com calor (heat treatment) and ‘tratada com calor’ (heat treated). However, in order to avoid errors of interpretation, these nomenclatures should be avoided because they are generic and traditionally used for the well-established process of artificial drying of wood. It is also strongly discouraged the use of ‘retificação térmica’ and ‘termorretificação’ as well as their derivatives ‘retificada termicamente’ and ‘termorretificada’.

Abstract This study intended to assess the effect of weather on the air-drying process of messassa wood (Brachystegia spiciformis Benth) in two areas of Mozambique (Machipanda and Beira city). First, the logs were sawn into 27 mm thick boards. Every five days the moisture content of the wood was determined by the control samples. For each region, the drying rate and wood quality post sawing and drying were estimated. The drying time differed between the regions under investigation, with Machipanda revealing the higher value. Messassa wood, which revealed a low drying rate (0.33% U/day), was categorized as slow drying wood. Both regions showed average final moisture content of 15.3% in the boards, with only slight variations in moisture inside the stacks. After outdoor drying, only a few defects were noted and as it was free from tensions, hence it was classified as good quality wood.

Abstract: A study of colour assessment, using the CIEL*a*b* system, was conducted with samples of Eucalyptus grandis wood thermally treated by the Brazilian industrial process of thermal modification, VAP HolzSysteme®, at three different temperatures, i.e. 140, 160 and 180 °C. Previous to the treatment, the samples were classified into three groups according to their distance to the wood pith, on the radial direction. All thermally modified samples presented a noticeable colour change, confirmed by high values of ΔE*. As the intensity of the treatment increased, the eucalypt samples presented an increase of red colour tone (a*) (up to 160 ºC) and a decrease of colour lightness (L*). Significant colour differences were found among the classified groups, for both untreated and thermally modified samples. The eucalypt samples groups showed different colour responses when thermally treated at 140 and 160 ºC. At 180 ºC the groups didn’t show a significant colour response variation.

Abstract: This study is a continuation of a previous study published in this journal, with the aim of evaluating the effect of the Brazilian industrial thermal modification process on some physical properties of Eucalyptus grandis juvenile wood. Flatsawn boards of juvenile wood were tested for four treatment levels: untreated and thermally modified wood at final cycle temperatures of 140 °C, 160 °C and 180 °C. Physical properties were assessed according to a standard of the Comisión Panamericana de Normas Técnicas and a method proposed by the specialized literature encompassing equilibrium moisture content (a measure of wood’s hygroscopicity), density (oven-dried and air-dried) and radial, tangential and volumetric swelling (from oven-dried to green moisture content). Thermally modified Eucalyptus grandis wood became less hygroscopic, more dimensionally stable (tangential and volumetric swelling) and less dense, even at the lowest temperature tested (140 °C), except for radial swelling, which did not differ from untreated wood.

ABSTRACT The objective of this study was to identify eucalyptus clones for the production of sawed timber based on dendrometric variables and longitudinal residual deformation (LRD), analyzing the correlation between these characteristics. 20 Eucalyptus grandis x Eucalyptus urophylla clones with 13 years of age were analyzed. The crown size, diameter at breast height (DBH) and bark thickness were measured. There was a significant difference between the clones for DBH, LRD and bark thickness. There was no significant correlation between DBH and DRL. The correlation was significant between DBH and crown size, its being possible to affirm that crown size affects the diametrical growth of trees. DBH and bark thickness were also significantly correlated, in so far as trees with a wider diameter possess thicker bark. It was possible to select clones with better potential for sawed timber production, that is to say, elevated DBH with a reduced LRD.

RESUMO A determinação dos gradientes de umidade é uma das etapas mais importantes na avaliação da qualidade da secagem da madeira. O objetivo geral do trabalho foi estudar a qualidade da secagem natural de tábuas de teca utilizando os gradientes de umidade na espessura e no comprimento. Seis tábuas representativas (40 × 180 × 2.300 mm) foram amostradas de uma pilha de secagem natural sob cobertura, divididas em 30 partes iguais no comprimento e medidas com um medidor elétrico de umidade resistivo, resultando em quatro tratamentos: duas profundidades (1/4 e 1/2 da espessura) e duas superfícies (interna e externa) de medição. Dentre as principais conclusões, a qualidade da secagem natural pôde ser considerada boa, principalmente por dois motivos: i) os gradientes de umidade médios na espessura foram comparáveis àqueles reportados na literatura para secagem artificial de tábuas menos espessas; ii) a amplitude da umidade média entre tábuas (2,5 p.p.) foi satisfatória para um processo de secagem conduzido sem controle das variáveis ambientais. O gradiente de umidade no comprimento foi completamente diferente daqueles reportados na literatura, nos quais o topo de nenhuma tábua apresentou menor umidade do que as porções compreendidas entre os topos.

ABSTRACT The determination of moisture content gradients is one of the most important steps for assessing the quality of wood drying. The general aim of this work was to study the quality of air-dried teakwood boards according to the gradients of moisture content in thickness and length. Six representative boards (40 × 180 × 2,300 mm) were sampled from a stack air-dried under shelter, divided into 30 equal parts in length and measured with a resistance moisture meter, resulting in four treatments: two depths (1/4 and 1/2 thickness) and two surfaces (inner and outer) of measurement. As main results, we can conclude that the air-drying quality can be considered good, mainly for two reasons: i) the average moisture content gradients in thickness were comparable to those reported in literature for kiln-drying of less thick boards; ii) the range of average moisture content among boards (2.5 p.p.) was satisfactory for a drying process carried out without environment control. Length moisture content gradient was completely different from that reported in literature, in which no board tops had smaller moisture content than the parts comprehended in between the tops.

RESUMO Existem atualmente cinco principais processos de modificação térmica em operação na Europa, que aumentam a estabilidade dimensional e a resistência da madeira à biodeterioração, porém, não são eficientes contra o ataque de térmitas. Na verdade, existe pouca pesquisa a respeito do efeito da modificação térmica da madeira na resistência à biodeterioração por térmitas, sejam subterrâneas ou de madeira seca. O objetivo desta pesquisa foi avaliar o efeito do processo brasileiro de modificação térmica VAP HolzSysteme(r) na resistência da madeira de Eucalyptus grandis ao ataque de térmitas de madeira seca Cryptotermes sp. Para tanto, foram testados cinco tratamentos: madeira não tratada de eucalipto, madeira de eucalipto modificada termicamente a três temperaturas finais (140, 160 e 180°C) e madeira de pinus (controle). O ataque foi avaliado em termos de perda de massa, escore médio das notas do desgaste, número de orifícios e mortalidade das térmitas, de acordo com o método proposto pelo Instituto de Pesquisas Tecnológicas de São Paulo. Semelhante aos processos europeus de modificação térmica, o processo brasileiro VAP HolzSysteme(r) também não foi eficaz para melhorar a resistência da madeira de eucalipto ao ataque das térmitas de madeira seca, pelo menos nas condições avaliadas.

ABSTRACT There are currently in operation five major European industrial processes for wood thermal modification. They improve wood's dimensional stability and decay resistance, but are not efficient against termites attack. In fact, there is little research about the effect of thermal modification on wood resistance to termites, whether subterranean or dry-wood termites. The aim of this study was to evaluate the effect of the Brazilian process of thermal modification (VAP HolzSysteme(r)) on the resistance of Eucalyptus grandis wood to attack by Cryptotermes sp. dry-wood termites. Five treatments were tested: untreated eucalypt wood, thermally modified eucalypt wood at three final temperatures (140, 160 and 180 °C) and pine wood (control). The attack was evaluated in terms of mass loss, mean score of wear grades, number of holes and termites mortality, according to a Brazilian method proposed by the Technological Research Institute of São Paulo. Similarly to the European processes of thermal modification, the Brazilian VAP HolzSysteme(r) was not effective to improve wood resistance to dry-wood termites attack, at least in the evaluated conditions.

This article reports the first study of the influence of the Brazilian process of thermal modification called VAP HolzSysteme® on the chemical composition of Eucalyptus wood. Flatsawn boards of Eucalyptus grandis juvenile wood were tested for four treatment levels: untreated and thermally modified at final cycle temperatures of 140, 160 and 180 °C. Chemical analyses were carried out according to the standards of the Technical Association of the Pulp and Paper Industry and encompassed total extractives, insoluble lignin, holocellulose (cellulose + hemicelluloses) and solvent soluble extractives in water (cold and hot) and ethanol:toluene (1:2 v.v.) mixture. The chemical composition of thermally modified Eucalyptus grandis juvenile wood was significantly changed by the VAP HolzSysteme® process compared to untreated wood. Only the wood thermally modified at final cycle temperature of 180 °C was significantly different for all the chemical analyses performed compared to untreated wood.

This article reports continuation of a study of the influence of the Brazilian process of thermal modification called VAP HolzSysteme® on the chemical composition of Eucalyptus wood. Flatsawn boards of Eucalyptus grandis juvenile wood were tested for four treatment levels: untreated, and thermally modified at final cycle temperatures of 140 °C, 160 °C or 180 °C. Chemical analyses were carried out according to the standards of the Technical Association of the Pulp and Paper Industry and encompassed 1% NaOH solubility and ash content. The 1% NaOH solubility increased in the wood thermally modified at 140 °C and 160 °C in relation to the untreated wood, but did not increase further 180 °C, indicating that the treatment at 180 °C was not enough to cause more degradation of hemicelluloses. In practice, the thermal modification process had no effect on the ash content of wood. The statistical difference observed between the treatment levels untreated and 160 °C (0,04 percentage points) can be attributed to the heterogeneity of wood as a material.

RESUMO Este trabalho é a continuação da pesquisa de Klitzke & Batista (2010), e teve como objetivo principal avaliar se a qualidade da madeira na metodologia da secagem drástica a 100 °C corresponde àquela da secagem convencional. Utilizou-se madeira de 11 anos de Eucalyptus saligna, Eucalyptus grandis e Eucalyptus dunnii, que foram secas conjuntamente em uma câmara-piloto convencional, realizando-se três repetições. Os defeitos de secagem avaliados foram rachaduras de superfície e de topo, encanoamento e colapso, dos quais foi produzido um escore médio por espécie, que foi comparado com o escore de defeitos do ensaio de secagem drástica, e também com a densidade básica e a contração volumétrica total da madeira. Eucalyptus grandis e Eucalyptus saligna tiveram a melhor qualidade de secagem. Foi rejeitada a hipótese de se poder utilizar o escore de defeitos do ensaio de secagem drástica como forma de prever a qualidade da secagem convencional das espécies estudadas.

ABSTRACT This research is a continuation of Klitzke & Batista (2010) work. The main objective was to assess whether the wood quality in the methodology of drastic drying test at 100 °C corresponds to that of conventional kiln drying. It was used 11 years old Eucalyptus saligna, Eucalyptus grandis and Eucalyptus dunnii woods, which were kiln dried together in the same batch in a pilot scale kiln, doing three repetitions. Drying defects evaluated were end and surface cracks, cupping and collapse, which generated a mean score by species, which was compared to the score of defects of the drastic drying test, as well as to the basic density and the total volumetric shrinkage. Eucalyptus grandis and Eucalyptus saligna had higher wood quality in conventional drying than Eucalyptus dunnii. It was rejected the hypothesis of using the score of defects in drastic drying test as a way of predicting the quality of conventional kiln drying.

RESUMO A indústria brasileira comumente seca diferentes espécies de eucalipto em uma mesma carga de secagem convencional, seja pela dificuldade de identificação das espécies, híbridos e clones, seja para melhor utilizar o equipamento. No entanto, essa prática não é recomendada na literatura específica. O objetivo deste estudo foi verificar a qualidade da secagem convencional conjunta da madeira de Eucalyptus saligna, Eucalyptus grandis eEucalyptus dunnii oriundas de plantios clonais. Para tal, foi realizada a secagem de três cargas com as três espécies conjuntamente em uma câmara-piloto de secagem convencional. Os critérios utilizados para analisar-se a qualidade da secagem foram: umidade final, rachaduras de topo, rachaduras de superfície, encanoamento, colapso, gradiente de umidade e tensões de secagem.Eucalyptus grandis apresentou a melhor qualidade de secagem, seguido pelo Eucalyptus saligna, e ambas as espécies possuem potencial para serem secas conjuntamente. Eucalyptus dunnii apresentou baixa qualidade de secagem, esta espécie não deve ser seca conjuntamente com Eucalyptus grandis eEucalyptus saligna. A densidade básica e a retratibilidade foram bons critérios para a expectativa de qualidade da secagem de Eucalyptus spp., em que espécies menos densas e mais estáveis dimensionalmente apresentaram melhor qualidade de secagem. O programa de secagem utilizado deve ser modificado para a secagem futura dessas espécies, notadamente no tocante aos períodos de uniformização e condicionamento, que foram considerados insuficientes.

ABSTRACT The Brazilian industry commonly dries different species of eucalypt in a same load because of the difficulty of identifying the species, hybrids and clones, and also by optimizing the use of the kiln. However, this practice is not recommended in the literature. The aim of this work was to verify the quality of grouped conventional drying of Eucalyptus saligna, Eucalyptus grandisand Eucalyptus dunnii from clonal plantations. To this end, three loads were dried with the three species together in a pilot conventional dry kiln. The criteria used to analyze the quality of dried wood were final moisture content, end checks, cupping, collapse, moisture gradient and drying stresses. Eucalyptus grandis showed the best quality of drying, followed by Eucalyptus saligna, and both species have potential to be kiln dried together. Eucalyptus dunnii had the worst quality of drying, and should not be kiln dried together withEucalyptus grandis and Eucalyptus saligna.The basic density and shrinkage were good parameters for the expected quality of the drying of eucalyptus species, in which less dense and more dimensionally stable species had better quality of drying. The drying schedule used must be modified to further drying of these species, especially regarding to uniformity and conditioning periods, which were considered insufficient.