European Journal of Wood and Wood Products最新文献

{"title":"Structure and physical properties of high-density bamboo scrimber made from refined bamboo bundles","authors":"Caimei Liu, Wu Xizhi, Xianjun Li, Xiubo Liu","doi":"10.1007/s00107-024-02120-z","DOIUrl":"https://doi.org/10.1007/s00107-024-02120-z","url":null,"abstract":"<p>Bamboo is comprised of parenchyma and vascular bundles, which contain vessels, sieve tubes, and fiber cells exhibiting numerous cavities or loose structures. Bamboo bundles undergo a series of mechanical rolling and disintegration processes to transform them into longitudinally continuous and transversely separated bamboo bundles and there is still a significant amount of vascular bundles and parenchyma that remain undissociated. Partial vessels, sieve tubes, and a majority of the parenchyma cell cavities are still discernible in the bamboo scrimber through the process of hot pressing, which significantly diminishes properties of bamboo scrimber, such as the strength, rigidity, and the water resistance. Therefore, this paper presented a new type of bamboo scrimber made from refined bamboo bundles, which is called high-density bamboo scrimber. That is, based on conventional bamboo bundles, a small amount of NaOH was employed to selectively eliminate a portion of the hemicellulose and soften bamboo bundles. Subsequently, a mechanical hammering technique was employed to disintegrate the bamboo bundles into single vascular bundles and surrounding parenchyma. This process increased the resin infiltration pathways and a multi-scale bonding interface structure was formed, and the densification and physical properties of the bamboo scrimber were improved. In high-density bamboo scrimber, the fiber cells maintained their original structural morphology, while the vessel cells and parenchyma cells were completely compacted, resulting in indistinguishable cell contours, and there was no discernible demarcation between the vascular bundles and parenchyma. Compared to ordinary bamboo scrimber, the bending strength, bending modulus, and maximum displacement of high-density bamboo scrimber exhibited a significant increase of 40.1%, 37.3%, and 18.2% respectively. The water resistance, surface roughness after sanding, and mildew resistance of this particular bamboo scrimber were better than those of ordinary bamboo scrimber. High-density bamboo scrimber exhibited a broader spectrum of applications within architectural structures.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"16 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel thermally regenerated flexible cellulose-based films","authors":"Rui Moreira, Rafael C. Rebelo, Jorge F. J. Coelho, Arménio C. Serra","doi":"10.1007/s00107-024-02126-7","DOIUrl":"https://doi.org/10.1007/s00107-024-02126-7","url":null,"abstract":"<p>In this work, cellulose powder obtained by acid hydrolysis of industrial Eucalyptus kraft pulp was dissolved in NaOH/Urea/H₂O system (7/12/81 wt%) in a concentration of 6% (w/v). Cellulose films were prepared by spreading the dissolved cellulose over glass plates, followed by thermal regeneration – a novel approach reported here for the first time. To obtain final flexible films, plasticization was carried out by immersion in aqueous glycerol solutions of various concentrations (10 to 70 wt%) and hot-pressing (at 0.1 MPa and 105 ºC) was used to dry and compress the cellulose films. The resulting films were characterized by Attenuated Total Reflectance Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction, contact angle measurements, transparency analysis, and gas permeabilities (oxygen and water vapor). Highly flexible films containing up to 50 wt% of glycerol were successfully obtained, exhibiting no glycerol release upon manual handling. Overall, the produced films demonstrated dense and compact structure, good transparency, flexibility and malleability, and very low oxygen permeability.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"93 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141969328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigations on the behaviour of structural-sized wood-CFRP composite beams in local fire","authors":"Bartosz Kawecki, Michał Pieńko, Tomasz Lipecki, Andrzej Stachowicz","doi":"10.1007/s00107-024-02130-x","DOIUrl":"https://doi.org/10.1007/s00107-024-02130-x","url":null,"abstract":"<p>The study involved combustion of 24 structural-sized beams under three-point bending subjected to substantial loading prior to ignition, reaching 90% of characteristic load-carrying capacity. A localised fire exposure zone was established proximal to the region experiencing the highest bending moment. The specimens were categorised into two groups: the first consisted of tituted by glued-laminated timber (B), and the second comprised wood-CFRP (carbon fibre reinforced polymer) composite (BW). Initial measurements encompassed pre-ignition static deflection and load. Subsequently, the specimens underwent controlled combustion, during which parameters including burning duration and deflection up to failure, were documented. Following cooling with sand, two cross-sectional slices were extracted from each fractured beam, enabling to find vector-based contours of the remaining cross-section. The charring rate and the approximate heat flux density for each test were determined, enabling a direct comparison of the results. A statistically significant number of specimens was examined, facilitating a comparative analysis between reinforced and unreinforced beams concerning failure time and form. Incorporating CFRP tapes among wooden constituents was found to increase the fire resistance of the structure, however, the thickness of the wooden material enveloping the CFRP composite emerges as a pivotal determinant. This issue needs thorough testing under standard fire in the future. Nevertheless, the fact is that adding CFRP tapes engenders a distinct form of beam collapse, transitioning from instantaneous cracking in B-beams to ductile failure in BW-beams.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"374 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141969268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of wood chips terminal velocity and some morphological properties in a wind tunnel experiment","authors":"Gábor Németh, Zoltán Kocsis, Endre Magoss","doi":"10.1007/s00107-024-02123-w","DOIUrl":"https://doi.org/10.1007/s00107-024-02123-w","url":null,"abstract":"<p>The removal of wood dust and chips from the work area is also important for occupational health safety regulation and to avoid the risk of fire and dust explosion. Knowledge of the terminal velocity is an important condition for the effective and economical operation of commonly used wood dust-chip extraction systems. While the largest particles are important from the point of view of the operation of the extraction system, knowledge of the terminal velocity of small particles (under 1 mm) is desirable from the point of view of separation and occupational health safety. New measuring and calculation method is developed in order to determine the terminal velocity of wood particles. We built an experimental device to measure the terminal velocity of wood dust-chip particles, and using the experimental results, we modified the calculated terminal velocity based on the modified equivalent particle density (100–130 kg/m³) in the 1–150 μm size range. The terminal velocity of wood particles under 150 μm more and more deviates from the theoretical values. As a result of mechanical processing, the resulting wood particles’ shape is in most cases flat. The average thickness of the wood particles is mainly determined by the sawing parameters. The flat shape of particles increases the specific surface area in a certain extent depending on the distribution parameters.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"6 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on surface creation and wettability of bamboo through abrasive belt sanding","authors":"Jian Zhang, Weiyu Jiang, Yunhao Cui, Jun Qian","doi":"10.1007/s00107-024-02128-5","DOIUrl":"https://doi.org/10.1007/s00107-024-02128-5","url":null,"abstract":"<p>In manufacturing bamboo products, sanding is an important method to make surface modification. In this study, mechanical sanding experiments were carried out to investigate the resultant surface creation and wettability. Electrostatic sand-planting abrasive belts with meshes of P60, P80, P120 were selected as abrasive tools. Dimensional bamboo strips were used to prepare workpieces with wax layer and pith film completely removed. Here, we carefully considered structural characteristics of bamboo, including internode and node areas at bamboo skin (BS) and pith ring (BP) sides. Dynamic contact angles were measured to evaluate surface wettability. In contrast with the unsanded surfaces, contact angles of sanded bamboo surfaces significantly declined at the end moment of 12s. Interestingly, node areas at BS and BP sides basically exhibited lower contact angles after sanding than internode areas. Surface morphology is a key component of surface creation, the impact of which on the wettability was studied. Specifically, mechanical sanding caused noticeable plowed ridges and much micro-fibrillation, leaving anatomical cavities like fractured vessels and pits exposed. Surface roughness was measured by a non-contact 3D profilometer with parameters of <i>S</i>a, <i>S</i>sk, <i>S</i>ku, <i>S</i>tr, <i>S</i>dr, <i>S</i>pc. The quantitative analysis presented that the <i>S</i>a and <i>S</i>dr values of sanded surfaces can be sorted as P60 &gt; P80 &gt; P120. Importantly, the results indicate that a rougher bamboo surface with greater <i>S</i>a does not definitely result in better wettability. Detailed information on surface creation should be taken into account.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"363 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141880846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical and thermal analysis of basalt grid reinforced particleboards containing flame retardants","authors":"Aaron Kilian Mayer, Sascha Brinker, Carsten Mai","doi":"10.1007/s00107-024-02127-6","DOIUrl":"https://doi.org/10.1007/s00107-024-02127-6","url":null,"abstract":"<p>Flame retardants and other additives can reduce the performance of adhesives used to produce wood-based panels such as particleboards (PB). Basalt reinforcement was evaluated to compensate for the loss of bending strength to allow the panels to be used in the construction sector. A basalt grid with a grammage of 200 g m⁻² was used to reinforce PB containing 15 m% nitrogen-phosphate based flame retardant. The modulus of rupture (MOR) and modulus of elasticity (MOE) of the reinforced panels were higher (69% and 24%, respectively) than those of corresponding reference panels. The thermal analysis revealed that the addition of the flame retardant could result in the PB being upgraded to Euroclass B with a reduced crack formation, as identified via 3D-microscopy. Consequently, the use of basalt grid as a reinforcement material could be a way to reinforce panels that contain strength-reducing additives.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"18 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141880848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lipophilic and polar extracts in the cork-rich bark of the Miombo species Parinari curatellifolia","authors":"Abílio Santos Malengue, Rita Simões, Isabel Miranda, Helena Pereira","doi":"10.1007/s00107-024-02119-6","DOIUrl":"https://doi.org/10.1007/s00107-024-02119-6","url":null,"abstract":"<p>The Miombo species <i>Parinari curatellifolia</i> has a bark with a cork-rich rhytidome that was studied here for the first time regarding extract yields and composition, using the complete rhytidome and also the separated cork fraction. The objective was to analyse their potential as sources of extracts with antioxidant activities aiming at increasing the species’ valorization and our knowledge on cork-rich barks.The content in total extractives was 6.1% and 8.4% in rhytidome and cork, respectively, with the lipophilic extracts soluble in dichloromethane corresponding to 23% and 38% of the total extracts, respectively. In cork, triterpenes and sterols were the main families of lipophilic components (58.9% and 20.8% of all compounds, respectively) while the rhytidome lipophilic extracts had a much higher content of long-chain lipids, including alkanoic acids and ɑ,ω-diacids (28.8% and 7.0%, respectively), with terpenes representing 27.7% and sterols 8.4% of all compounds. Aromatics were also present in significant amounts of 12.1%. Triterpenes included compounds known for various therapeutic properties, e.g. betulinic acid, corosolic acid, maslinic acid and ursolic acid, thereby explaining the use of <i>P. curatellifolia</i> in traditional medicine. Ethanol-water extracts contained phenolics, flavonoids, and tannins, and showed low (cork) or good (rhytidome) antioxidant properties. The outerbark of <i>P. curatellifolia</i> is therefore a potential source of bioactive compounds.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"6 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141880842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance of treated wooden electricity distribution poles in service in Uganda","authors":"E. Otuko, P. Mugabi, T. Nabatanzi, P. Kityo, P. Kakeeto, I. Kinhonhi, F. Kansiime","doi":"10.1007/s00107-024-02104-z","DOIUrl":"https://doi.org/10.1007/s00107-024-02104-z","url":null,"abstract":"<p>Chromated Copper Arsenate (CCA) and Creosote-treated eucalypts are the preferred material for wooden electricity distribution poles in Uganda despite their susceptibility to biodegradation. This study assessed the extent of premature pole failure, its causes, and the service life of poles in Uganda. A mixed-methods approach was used to collect and analyse data including: (i) Secondary data extraction (ii) stakeholder interviews (iii) focus group discussions, and (iv) field observations. The results showed that over 8.3% of poles supplied between 2017 and 2021 failed prematurely translating to over USD. 8.8 million in replacement costs. Fungal decay and termite damage were the leading causes of pole failure accounting for 85.3% of CCA-treated poles and 67% of creosote-treated poles. Further analysis indicated that the average service life of poles in Uganda was about 10 years. The cause of pole failure, point of failure and geographic location of the pole in service were identified as the main factors to explain premature pole failure. To minimise failure, it is recommended that pole sourcing, handling, seasoning, and preservative treatment are conducted according to applicable country and regional standards.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"213 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141871641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of wood particles polyesterification with sorbitol and citric acid on the properties of particleboard produced with the use of PF/pMDI adhesive","authors":"Jakub Kawalerczyk,&nbsp;Marcin Kuliński,&nbsp;Andrea Majlingová,&nbsp;Dorota Dukarska,&nbsp;Radosław Mirski","doi":"10.1007/s00107-024-02124-9","DOIUrl":"10.1007/s00107-024-02124-9","url":null,"abstract":"<div><p>This study investigated the effect of pine particle polyesterification with the mixture of sorbitol and citric acid (SCA) on the properties of particleboard bonded with the PF/pMDI hybrid resin. The use of SCA with a concentration of 35% contributed to improvement in the internal bond of the particleboards, their water resistance and dimensional stability. However, lowering the concentration to 25% resulted in a deterioration of the properties of produced materials. The effect of different loadings of pMDI in the PF/pMDI resin (0%, 5%, 15%, 25%) was also investigated and the outcomes showed a positive effect of the share of 15% and 25%. Furthermore, boards made of treated particles were characterized by slightly better flammable properties (lower mass loss, flashing point temperature and delayed ignition), and the visibility of the effect increased with the increase in the concentration of the impregnate. The results also indicate that the introduction of pMDI may also influence the ignition of the board.</p></div>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"82 5","pages":"1725 - 1737"},"PeriodicalIF":2.4,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00107-024-02124-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141871455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Incorporation of oxidized paraffin into a composite with modified polyethylene wax improves the surface coating and interfacial properties of hot-waxed wood","authors":"Kangren Niu,&nbsp;Liangliang Zhang,&nbsp;Shuning Li,&nbsp;Zhenming Chen,&nbsp;Zhipeng Sun,&nbsp;Kuiyan Song,&nbsp;Xiaozhou Song","doi":"10.1007/s00107-024-02117-8","DOIUrl":"10.1007/s00107-024-02117-8","url":null,"abstract":"<div><p>Modified polyethylene wax (MPEW) has an excellent performance in wood hot-waxing. However, MPEW hot-waxed wood still has deficiencies in terms of hydrophobicity, wax coating adhesion, and thermal stability. Here we prepared a composite wax by combining the oxidized paraffin wax (OPW) with MPEW in the hot-waxing treatment of wood to enhance the performance of MPEW hot-waxed wood. The impact of the amount of OPW on the surface/interface properties of the hot-waxed wood was investigated and compared with those of wood treated with MPEW alone during hot waxing. Our results demonstrate that the inclusion of OPW endows the wax coating with higher surface roughness and lower surface energy. It also enhances the penetration of MPEW into the wood and promotes the wax filling in the lumen of wood cells, resulting in a more uniform distribution of wax deposited in the cell lumina and an increased surface water contact angle of the hot-waxed wood. Additionally, this inclusion slows down the water absorption. On the other hand, there is the inhibitory effect of OPW on the thermal decomposition of MPEW, thereby enhancing the thermal stability of hot-waxed wood. By introducing more active groups, it improves the reaction probability between MPEW and the hydroxyl groups in the wood, which further strengthens the bond at the wax-wood interface, leading to a reduction in the amorphous wood components. At a mass ratio of 70/30 for MPEW to OPW, composite wax hot-waxed wood with better hydrophobicity, adhesion, and thermal stability can be obtained.</p></div>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":"82 5","pages":"1697 - 1711"},"PeriodicalIF":2.4,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141871642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}