Maderas. Ciencia y Tecnología <p>&nbsp;</p> <p>&nbsp;</p> <table style="margin-top: -250px; width: 1025px; height: 672px;"> <tbody> <tr> <td style="width: 30%;"><strong><span style="color: #ffffff; text-align: center;"><img src="/public/site/images/visepul/cover-3d-22(2)1.png"></span></strong></td> <td style="width: 30%;"> <div class="issueCoverDescription"> <div class="description"> <p><img style="width: 30px;" src="" alt=""> <a href="">Full Text PDF</a></p> <p><img style="width: 30px;" src="" alt=""> <a href="">e-book versio</a>n</p> <p><a href=""><img style="width: 30px;" src="" alt=""></a> <a href="">mobile version</a></p> <p><img style="width: 30px;" src="" alt="">&nbsp; <a href=";pid=0718-221X20200050&amp;lng=es&amp;nrm=iso">XML</a></p> </div> </div> </td> <td style="width: 30%;"> <p>Editor-in-Chief: <a href="" target="_self">Rubén A. Ananias</a><span id="result_box" class="short_text" lang="en"><br>Technical Editor</span>: <a href="">Linette Salvo S.<br></a>Digital Manager: <a href="">Victor Sepúlveda V.</a><br>E-mail :<a href=""></a><br>E-mail :<a href=""></a><br><br>2018 Journal Impact Factors:<br> 2-years: 1.4<br>5-years: 1.5<br> Frequency: 4 issues by year.<br>January, April, July, October<br>ISSN 0718-221X online version.<br>ISSN 0717-3644 printed version.</p> </td> </tr> </tbody> </table> en-US (Ruben A. Ananias.) (Victor Sepulveda Villarroel) Thu, 01 Oct 2020 00:00:00 -0300 OJS 60 Variability in the physico-chemical properties of wood from Eucalyptus robusta depending on ecological growing conditions and forestry practices: The case of smallholdings in the Highlands of Madagascar <p>This study set out to determine which environmental factors of growth and silvicultural practices can affect the properties of <em>Eucalyptus robusta</em> coppice wood and also to study variability in those properties depending on the factors. Hundred and thirty-five coppice logs aged 2 to 10 years were collected from five zones in the Highlands of Madagascar. Wood density at 12% moisture content was measured by X-ray microdensitometry. Chemical properties, such as the total extractives, Klason lignin and holocellulose contents were predicted using near infrared spectrometry prediction models. The results significantly showed (p-value&lt;0.001) that wood density (0.543 – 0.836<sup>-3</sup>), total extractives (3.1 – 9.8%) and Klason lignin content (24.6 – 35.3%) increased with age, with the</p> <p>opposite occurring for holocellulose (63.8 – 69.9%). Wood density also varied significantly (p-value&lt;0.001) depending on the zones, which was not the case for chemical properties. The densest woods were found at the hottest zones with less acid soils. Woods were less dense in zones, characterized by high rainfall and a soil rich in nitrogen and organic carbon. The plantation spacing, elevation of the zone and soil texture did not significantly affect wood properties.</p> Zo Elia Mevanarivo, Tahiana Ramananantoandro, Mario Tomazello Filho, Alfredo Napoli, Andriambelo Radonirina Razafimahatratra, Herintsitohaina Ramarson Razakamanarivo, Gilles Chaix ##submission.copyrightStatement## Thu, 01 Oct 2020 00:00:00 -0300 Hydrothermal treatments to promote surface inactivation and increased flexibility in three hardwoods <p>In the present study, three juvenile hardwoods (namely sycamore, pecan and london plane) were treated by boiling, steaming and microwave. Trees from <em>Platanus</em> x <em>acerifolia</em> (sycamore), <em>Carya illinoinensis</em> (pecan) and <em>Luehea divaricata</em> (london plane) were selected in homogeneous forests located in southern Brazil. Each hydrothermal treatment was performed for 60 min. In general, the hydrothermal treatments caused a certain surface inactivation effect, which was marked by decreased surface roughness, increased hydrophobic character and darkened colour patterns. Also, both decreased stiffness and strength, as well as increased deflectibility were obtained. These mechanisms were attributed to degradation in fine segments from amorphous polysaccharides, leaching of some organic extractives and fragmentation of lignin, as indirectly indicated by infrared spectra.</p> Matheus Lemos de Peres, Rafael de Avila Delucis, Rafael Beltrame, Darci Alberto Gatto ##submission.copyrightStatement## Thu, 01 Oct 2020 00:00:00 -0300 Durability of eucalypts wood in soil bed and field decay tests <p>This evaluated the natural resistance of wood from seven <em>Eucalyptus </em>trees in field decay and soil bed tests. Two 12-year-old trees were randomly sampled per species, with 2,2 m logs being obtained from the &nbsp;basal section of each tree. The samples were taken in two positions in the radial direction of the stem (middle heartwood and transition zone; containing heartwood and sapwood). The field decay tests were installed in three municipalities in the southern state of Espírito Santo, and the soil utilized soil from the three field decay test areas. The field decay tests were evaluated after six, 12 and 18 months after installation and the soil bed tests after six months. The Scott-Knott test (p ≤ 0,05) was used in the analysis and evaluation of the tests. The sapwood-heartwood (transition region) exhibited the greatest mass losses for the field decay and soil bed tests. On average, for the soil bed test the lowest mass losses were observed for the soil of Vargem Alta (5,00 %), with greater mass losses observed for São José do Calçado (7,05 %) and Jerônimo Monteiro (9,90 %). In the field decay test the organisms present in the soil of São José do Calçado and related to the organic matter content <em>Eucalyptus grandis</em> and <em>Eucalyptus saligna</em> more intensely.</p> Pedro Nicó de Medeiros Neto, Juarez Benigno Paes, José Tarcísio da Silva Oliveira, João Gabriel Missia da Silva, José Clailson Franco Coelho, Libânia da Silva Ribeiro ##submission.copyrightStatement## Thu, 01 Oct 2020 00:00:00 -0300 The efficiency of Pistacia atlantica gum for increasing resistance of rapeseed oil-heat treated wood to fungal attacks <p>In this research, we used <em>Pistacia atlantica</em> gum during cooling phase of oil-heat treatment of poplar wood (<em>Populus deltoids</em>) to improve its resistance to the white-rot fungus <em>Trametes versicolor</em> and growth of the mold fungus <em>Penicillium expansum</em>. Thermal modification was carried out using rapeseed oil at 180 °C, 200 °C and 220 °C for 2 hours and 4 hours. The modified wood specimens were then directly cooled in the oil containing 0 %, 5 % and 10 % (w/w) of the gum at 25 °C for 30 minutes. The chemical constituents of the essential oil extracted with a Clevenger type apparatus were determined by chromatography–mass spectrometry&nbsp;(GC-MS). The amounts of α-pinene, β-pinene and α-terpinolene of the essential oil were 60,2 %, 8,7 % and 3,9 %, respectively. The mold resistance was greatly improved, while the improvement against the decay fungus was only observed for the specimens modified at 180 °C. Our results confirmed that the enhanced fungal resistance was not only due to the presence of monoterpenes in the essential oil, but also to a further reduction in the hygroscopicity of the treated wood.</p> Morad Mahmoud Kia, Asghar Tarmian, Ali Naghi Karimi, Hadi Gholamiyan, Ali Abdulkhani, Mohamad Reza Mastri Farahani ##submission.copyrightStatement## Thu, 01 Oct 2020 00:00:00 -0300 Enhancing mechanical and surface properties of eucalyptus wood <p><em>Eucalyptus</em> is one of the most fast-growing trees. Therefore, in the last decades it has been extensively planted and harvested so that nowadays <em>Eucalyptus</em> is one of the most popular trees of the planet. There are many genres of this plant and they are often treated as a large bunch of the same timber characterized by moderate mechanical and surface properties which hinder their usage for any sight application (e.g. flooring, cladding, ceiling). In this study four species of <em>Eucalyptus</em>: <em>E. grandis</em>, <em>E. dunnii</em>, <em>E. cloeziana</em> and <em>E. tereticornis</em> were undergone to densification through hydro-thermo-mechanical treatment (HTM) first and then to oil heat-treatment (OHT) in order to improve their mechanical properties and hydrophobicity. It was observed that low density species (<em>E. grandis</em>) reaches higher compression degrees while heavier species (<em>E. tereticornis</em>) reach densities over 800 kg/m³; however, HTM decrease the variability of the properties. Treatments at higher temperature (160 °C) involves higher compression degree, lower set-recovery and higher surface hydrophobization, but also weaker mechanical properties. The hot oil post- treatment helps to contain the springback effect and to reduce the wettability of each specimen. Densified samples present similar surface hardness. The tailored application of the two treatments improves the properties of every <em>Eucalyptus</em> which can gain market also for nobler end-usages.</p> Anderson Pertuzzatti, Gianluca Tondi, Rodrigo Coldebella, Henrique W. Dalla Costa, Darci A. Gatto, André L. Missio ##submission.copyrightStatement## Thu, 01 Oct 2020 00:00:00 -0300