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(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 version</a></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=0718-221X20200001&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> Universidad del Bio-Bio en-US Maderas. Ciencia y Tecnología 0717-3644 Efficacy of alternative copper-based preservatives in protecting decking from biodegradation <p>The above-ground performance of decking treated with two alternative copper-based preservative formulations is being evaluated at a test site near Madison, Wisconsin, USA. Southern pine sapwood lumber specimens (38 mm by 140 mm by 910 mm) were pressure treated with 0,93 %, 1,40 % or 2,34 % (oxide basis) actives concentrations of a boron-copper formulation (BC) composed of 7,2 % copper hydroxide and 92,8 % sodium tetraborate decahydrate. Similar specimens were pressure-treated with 0,66 % or 1,32 % actives concentrations of a copper-zinc formulation (CZDP) composed of 18 % copper (CuO basis), 12 % zinc (ZnO basis), 14 % dimethylcocoamine and 56 % propanoic acid. In both cases untreated specimens and specimens treated with a 1% concentration of chromated copper arsenate Type C (CCA-C) were included for comparison.&nbsp; The specimens were installed on racks approximately 760 mm above the ground and periodically evaluated for extent of fungal decay and surface microbial growth. After 18 years in test specimens treated with the lowest solution concentration of BC (0,93 %) suffered substantial degradation and all but three replicates have failed. Obvious decay has not yet been detected in specimens treated to the highest BC concentration (2,34 %), but decay is suspected in one of these specimens. Decking specimens treated with CZDP exhibited no evidence of decay until year 17 when a fruiting body was observed on one specimen treated with a 0,66 % solution concentration. There has been no evidence of decay in specimens treated with 1,32 % CZDP or in either set of specimens treated with 1 % CCA-C. Both BC and CZDP-treated specimens were at least as effective as 1 % CCA-C in minimizing noticeable surface microbial growth. These decking studies confirm that relatively low copper concentrations can provide substantial protection for decking exposed in a moderate climate, and that the CZDP formulation is potentially more effective than the BC formulation. However, caution is warranted in extrapolating these findings to more severe climates and to construction designs that are more likely to trap moisture.</p> Stan T. Lebow Katie M. Ohno Patricia K. Lebow Michael H. West ##submission.copyrightStatement## 2020-07-01 2020-07-01 22 3 Evaluation of the calorific values of wastes from some tropical wood species <p>The paper aims to analyze and classified some exotic wood species from tropical Africa, on regard to calorific features, in order to view the ability of their biomass to be a solid, natural and renewable fuel.&nbsp; The calorific values of wood wastes of eight tropical species were determined using an oxygen bomb calorimeter. The tested specimens were conditioned at a moisture content of 10%, 20%, and 50%. The influence of moisture content on calorific value and density, heat release rate and calorific efficiency were also analyzed. The biggest high calorific value and low calorific value were obtained by Guaiac and Rose species (21200-20700 kJ/kg). Acajou had the lowest values of high calorific value and low calorific value (18929 and 18456 kJ/kg, respectively). For higher wood density (Guaiac) the higher calorific density was obtained. The moisture content of specimens had negatively influenced the calorific efficiency and rate of energy release. The ash content was below 4% with highest values for Guaiac (3.6%) and the lowest for Acajou (0.5%). The results showed that the analyzed tropical wood species had a forest calorific capacity with 23-47% higher than of European beech, thus can be considered a good potential as renewable energy resources.</p> Aurel Lunguleasa Cosmin Spirchez Octavia Zeleniuc ##submission.copyrightStatement## 2020-07-01 2020-07-01 22 3