Bulletin of the Transilvania University of Brasov. Series II: Forestry • Wood Industry • Agricultural Food Engineering

Bulletin of the Transilvania University of Brasov. Series II: Forestry • Wood Industry • Agricultural Food Engineering https://webbut.unitbv.ro/index.php/Series_II <h2>Aims & Scope </h2> BULLETIN OF THE TRANSILVANIA UNIVERSITY OF BRASOV SERIES II publishes high-quality scientific articles and review papers on forestry, wood engineering, and agro-food processing. Studies may deal with interdisciplinary aspects of sustainable forest management, the wood processing sector, and food processing, and food safety. Attention is given to the originality of papers and their impact on policy and practice, as well as their contribution to the advancement of knowledge. The Journal is indexed by Scopus (<a href="http://www.scopus.com/source/sourceInfo.url?sourceId=21100218054&origin=resultslist">http://www.scopus.com</a>), since 2012, EBSCO Publishing DataBase (<a href="http://webbut.unitbv.ro/public/site/documents/admin/a9h-subject.xls">http://www.ebscohost.com/titleLists/a9h-subject.xls</a>), since 2009, CAB Direct (<a href="https://www.cabdirect.org/cabdirect/search/?q=do%3a%22Bulletin%20of%20the%20Transilvania%20University%20of%20Bra%C5%9Fov%2C%20Series%20II%20-%20Forestry%2C%20Wood%20Industry%2C%20Agricultural%20Food%20Engineering%22">http://www.cabdirect.org</a>), since 2008, ProQuest Central (<a href="https://search.proquest.com/central/publication/105973/citation/47DDC2C5B560443FPQ/2?accountid=7257">https://search.proquest.com/central/</a>), since 2008, Crossref (<a href="https://search.crossref.org/?q=Bulletin+of+Transilvania+Series+II%3A+Forestry+Wood+Industry+Agricultural+Food+Engineering&from_ui=yes">https://search.crossref.org</a>), since January 2019 and is accredited by the Romanian National Council of Scientific Research (CNCS) in the <a href="https://uefiscdi.gov.ro/userfiles/file/IC6%202011/Reviste%20romanesti%20recunoscute%20de%20CNCSIS-%20categoria%20B_plus.pdf">category B+</a> of the scientific magazine. Senior-editor, Alexandru Lucian CURTU <a href="http://webbut.unitbv.ro/index.php/Series_II/about" target="_blank" rel="noopener">Read more</a> Open Access Statement <div>This is an open-access journal. All its content is freely available to the user to read, download, copy, distribute, print, search, or link to the full texts. </div> en-US editor.but@unitbv.ro (Prof. dr. eng. Alexandru Lucian CURTU) biblioteca@unitbv.ro (Corina Monica Pop) Fri, 19 Dec 2025 00:00:00 +0000 OJS 3.3.0.3 http://blogs.law.harvard.edu/tech/rss 60 Influence of Wood Moisture Content on the Heat Balances and Efficiencies of Concrete Pits During Steaming or Boiling Unfrozen Veneer Logs https://webbut.unitbv.ro/index.php/Series_II/article/view/11172 A model-based approach for determining the heat balances and efficiencies of concrete pits during steaming or boiling of unfrozen veneer logs presented. With the help of a personal 1D model, the heating durations of beech logs with a diameter of 0.4 m, initial temperature of 10°C, and moisture content of 0.4, 0.6, and 0.8 kg∙kg-1 were calculated at operating temperature of 80°C in the pit. Using the determined logs' heating times and our own stationary model of the heat balances of concrete pits during steaming or boiling logs, the change in the heat balances and efficiencies of a pit with working volume of 20 m3 and loading level of 45, 60, and 75%, depending on the logs' moisture content was calculated. It was found that the change of the logs' moisture content from 0.4 to 0.8 kg∙kg-1 at maximum possible loading level of 75% leads to a rise in the energy consumptions and heat efficiencies of the pit from 104.3 to 125.2 kWh∙m-3 and from 34.3 to 42.9%, respectively, during the steaming process, and also from 143.5 to 161.8 kWh∙m-3 and 24.9 to 33.2%, respectively, during the boiling process. Reducing the pit load level from 75 to 45% at 0.6 kg∙kg-1 causes a decrease in the pit efficiencies from 39.0 to 28.5% during the log steaming process and from 29.3 to 16.1% during the log boiling process. N. Deliiski , L. Dzurenda, P. Niemz, M. Campean, D. Angelski, P. Vitichev Copyright (c) 2025 Bulletin of the Transilvania University of Brasov. Series II: Forestry • Wood Industry • Agricultural Food Engineering https://webbut.unitbv.ro/index.php/Series_II/article/view/11172 Fri, 19 Dec 2025 00:00:00 +0000 Improving Mechanical and Physical Properties of Wood-Plastic Composites Using Natural Rubber Latex Sludge Waste https://webbut.unitbv.ro/index.php/Series_II/article/view/11175 The disposal of synthetic materials and industrial by-products hasbecome a pressing environmental issue, particularly in the wood and polymersectors. This study investigated the feasibility of utilising natural rubber latexsludge waste as a reinforcing filler in wood-plastic composites (WPCs). Theinfluence of latex sludge content (20-40 wt%) and particle size (≤149 μm, 149-400 μm, and 400-707 μm) on the mechanical, thermal and physical propertiesof WPCs were examined. The WPC panels were fabricated via twin-screwextrusion followed by hot compression moulding. The morphological analysisrevealed that finer sludge particles enhanced interfacial adhesion andhomogeneity. The thermal analysis demonstrated that the addition of latexsludge marginally improved the thermal stability of WPCs, with optimalperformance observed at intermediate particle size. Higher sludge contentincreased the modulus of rupture but reduced the stiffness and hardness,attributed to the elastic nature of the sludge. Using finer latex sludge particlessignificantly improved WPC flexural strength and hardness, while reducingwater absorption due to better matrix packing and decreased hydrophilicity.These findings highlighted the potential of latex sludge as a value-added fillerin WPCs, offering an innovative approach to waste valorisation and materialenhancement for sustainable industrial applications. C. Homkhiew, C. Srivabut, T. Ratanawilai, S. Rawangwong, U. Sookyung Copyright (c) 2025 Bulletin of the Transilvania University of Brasov. Series II: Forestry • Wood Industry • Agricultural Food Engineering https://webbut.unitbv.ro/index.php/Series_II/article/view/11175 Fri, 19 Dec 2025 00:00:00 +0000 Gluability of Thermally Modified Birch (Betula pendula Roth.), Aspen (Populus tremula), and Poplar (Populus x canadensis Moench) Veneers Using Commercial Adhesives https://webbut.unitbv.ro/index.php/Series_II/article/view/11177 With the increasing demand for renewable materials worldwide,the use of wood has become increasingly appealing. However, wood has somedrawbacks, and modification is the approach that tries to reduce them.Thermal modification of wood is a sustainable method that enhances itsbiological durability and dimensional stability. However, it results indiminished mechanical properties, posing challenges for its bondingapplications. This study focuses on determining the glueing quality of 3-plyplywood produced from thermally modified aspen (Populus tremula L.), birch(Betula pendula Roth.), and poplar (Populus x canadensis Moench) veneers.Plywood samples were prepared using commercially available adhesives -phenol formaldehyde, melamine urea formaldehyde, hybrid polymer, andpolyurethane. The thermal modification was carried out under vacuum(TERMOVUOTO process) and in a water steam environment (WTT –hydrothermal process). Adhesion quality was evaluated in accordance withthe EN 314 standard. Results indicated that plywood from the TERMOVUOTOprocess-modified veneers yielded higher tensile-shear strength than plywoodfrom WTT-modified veneers. Polyurethane and phenol-formaldehydeadhesives proved to be the most suitable for bonding thermally modifiedveneers, whereas the hybrid polymer is unsuitable for this purpose. The studycontributes to optimising the use of thermally modified veneers in producingplywood for outdoor applications or 3rd Service Class, as per EN 1995-1-1:2004/AC:2006 - Eurocode 5. A. Meija, U. Spulle, H. Sillers Copyright (c) 2025 Bulletin of the Transilvania University of Brasov. Series II: Forestry • Wood Industry • Agricultural Food Engineering https://webbut.unitbv.ro/index.php/Series_II/article/view/11177 Fri, 19 Dec 2025 00:00:00 +0000 Eco-Friendly Objects, Furniture and Lighting Fixtures Made of Recycled Wood Aiming at the Promotion of Eco- Friendly Practices Such as Closed-Cycle Economy Systems, while Focusing on the Energy Efficiency of the Interior Space https://webbut.unitbv.ro/index.php/Series_II/article/view/11179 The article presents a theoretical and practical study focused onenergy efficiency in interior, urban, and rural spaces through the reuse ofrecycled wood and the application of innovative and sustainable solutions fordesigning furniture and lighting objects. The study outlines fundamentalconcepts and research perspectives regarding the need to reduce the use ofprimary wood, a process aimed at minimising global deforestation and thedegradation of natural ecosystems. The paper also examines eco-friendlyobjects – furniture and lighting pieces – crafted from recycled wood, whichcombine both aesthetic and functional values and can be integrated intovarious types of interior spaces, whether residential or non-residential. Thesedesign concepts were developed by architecture students within theArchitecture of Interior Space course (fifth year, integrated studies),respecting the principles of the circular economy. The projects aim to reducewaste and extend the lifespan of products, while promoting national andEuropean policies of sustainability and energy efficiency in the architecturalfield. Furthermore, the article highlights the contexts in which the Republic ofMoldova can benefit from the support of the European Union in implementingsustainable development initiatives. These include projects andrecommendations targeting environmental protection, energy efficiency, andthe promotion of eco-conscious educational practices. The researchemphasises the dual role of such initiatives: to provide innovative designsolutions and to strengthen environmental responsibility within architecturaleducation and practice. A. Munteanu, T. Filipski Copyright (c) 2025 Bulletin of the Transilvania University of Brasov. Series II: Forestry • Wood Industry • Agricultural Food Engineering https://webbut.unitbv.ro/index.php/Series_II/article/view/11179 Fri, 19 Dec 2025 00:00:00 +0000 Evaluation of Hybrid Composite Materials for Cribbing Applications in Train Derailment Recovery https://webbut.unitbv.ro/index.php/Series_II/article/view/11181 Railway systems play a crucial role for transporting goods andpassengers. When derailments occur, cranes need a stable base to lift traincars, often relying on wooden sleepers arranged in cribbing structures.However, wood is heavy, susceptible to rot, and raises environmental issues.This study introduces a sustainable alternative through sandwich compositestructures featuring hybrid face sheets composed of recycled plastics (rHDPE,rLDPE, rPE) and wood flour from both softwood and hardwood. Ten differentmaterial ratios were prepared using twin-screw extrusion and compressionmolding to assess their mechanical properties. The optimal performing blendconsisted of 70% recycled plastic and 30% softwood flour, showing superiorstrength, surface hardness, and water resistance. The softwood plasticcomposite sheets exhibit higher flexural and compressive strength comparedto materials made from hardwood flour, suggesting that the type of woodflour used influences the overall strength of the composites. Additionally,using rHDPE as the core material further improves the mechanical properties.The sandwich structure with an HDPE plastic core layer showed superiorperformance in terms of parallel compression, bending resistance, and surfacehardness when compared to structures with core layers made of other typesof plastics. When compared to conventional wood, the newly developedcomposite material is lighter in weight, more durable, and exhibits much lowerwater absorption. This innovative material provides an eco-friendly andeffective substitute for traditional wooden sleepers, promoting a moresustainable and robust railway infrastructure. T. Ratanawilai, M. Teh, M.A. Hayimasae, P. Soasuwan, N. Patthamin, N. Jaturonlux Copyright (c) 2025 Bulletin of the Transilvania University of Brasov. Series II: Forestry • Wood Industry • Agricultural Food Engineering https://webbut.unitbv.ro/index.php/Series_II/article/view/11181 Fri, 19 Dec 2025 00:00:00 +0000 Mechanical, Physical, and Sound Absorption Properties of Wood-Based Composites Made from Krajood (Lepironia articulata) Using Isocyanate as Binder https://webbut.unitbv.ro/index.php/Series_II/article/view/11183 This study investigates the mechanical, physical, acoustic, andmorphological properties of composites prepared from Krajood (Lepironiaarticulata) fibers bonded with isocyanate binder. The wood-based werefabricated with different fiber lengths (10 mm, 20 mm, and mixed lengths)and varied fiber-to-binder ratios of 80:20, 85:15, and 90:10 wt% using acompression molding process. The results showed that tensile strength andsurface hardness significantly improved in composites with mixed fiberlengths, especially at an optimized fiber-to-binder ratio of 85:15 wt%.Additionally, water absorption and thickness swelling tests showed thathigher binder content and shorter fibers effectively reduced moisture uptake,enhancing dimensional stability. Composites containing mixed fiber lengthsshowed the lowest water uptake and swelling values due to improved fiberpacking density. Sound absorption analysis revealed superior acousticperformance at mid-range frequencies (500–2000 Hz) for composites with 20mm fibers and mixed fibers, attributed to increased internal porosity and fiberscattering. Optical microscopy analysis demonstrated that composites withmixed fiber lengths displayed the most uniform and compact surfacestructures, with minimal fiber pull-out and porosity, suggesting enhancedfiber dispersion and matrix encapsulation. These findings highlight the criticalrole of fiber length distribution and binder ratio in tailoring compositeproperties. The optimized Krajood composites demonstrated a favorablebalance between mechanical integrity, dimensional stability, and acousticefficiency, highlighting their potential for sustainable applications such as ecofriendlyinterior components, elderly-supportive furniture, and acousticpanels. C. Srivabut, P. Pantamanatsopa, C. Homkhiew, W. Boonchouytan, S. Rawangwong Copyright (c) 2025 Bulletin of the Transilvania University of Brasov. Series II: Forestry • Wood Industry • Agricultural Food Engineering https://webbut.unitbv.ro/index.php/Series_II/article/view/11183 Fri, 19 Dec 2025 00:00:00 +0000