Pub Date : 2022-07-01DOI: 10.4067/s0718-221x2022000100442
Rongrong Li, Chujun He, Wei-xing Xu, Xiaodong Wang
Due to the advantages of short treatment period, no wastewater and oil produced, the CO 2 laser is applied as an environment friendly thermal treatment for wood materials to improve the wood properties, such as ap-pearance, color and wettability, among others. However, the morphological features of treated wood surface are also changed, which have negative effects on wooden product properties. To reveal the change tendency of surface roughness during laser irradiation, the common indexes of average roughness (Ra) and mean peak-to-valley height (Rz) were chosen to evaluate the surface roughness. The response surface methodology was selected to arrange the experiments and analyze the influences of laser parameters on surface roughness. The results showed that the poplar wood got rougher with the increased laser power, but the surface roughness decreased with increased feed speed and path spacing, due to the total heat absorption varied under different com bination of laser parameters. The ANOVA results showed that the selected quadratic models for Ra , Rz , Ra and Rz were significant due to the values of probability value (“Prob>F”) less than 0,05. In this case, all the input laser parameters were also the significant model terms for variation of surface roughness. The values of correlation coefficient were very close to 1, which meant the selected quadratic models could give accurate prediction of surface roughness for laser treated wood. Therefore, it is of great significance to predict the surface roughness of the modified wood surface scientifically and to guide the selection of reasonable modifi cation process parameters.
{"title":"Prediction of surface roughness of CO2 laser modified poplar wood via response surface methodology","authors":"Rongrong Li, Chujun He, Wei-xing Xu, Xiaodong Wang","doi":"10.4067/s0718-221x2022000100442","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100442","url":null,"abstract":"Due to the advantages of short treatment period, no wastewater and oil produced, the CO 2 laser is applied as an environment friendly thermal treatment for wood materials to improve the wood properties, such as ap-pearance, color and wettability, among others. However, the morphological features of treated wood surface are also changed, which have negative effects on wooden product properties. To reveal the change tendency of surface roughness during laser irradiation, the common indexes of average roughness (Ra) and mean peak-to-valley height (Rz) were chosen to evaluate the surface roughness. The response surface methodology was selected to arrange the experiments and analyze the influences of laser parameters on surface roughness. The results showed that the poplar wood got rougher with the increased laser power, but the surface roughness decreased with increased feed speed and path spacing, due to the total heat absorption varied under different com bination of laser parameters. The ANOVA results showed that the selected quadratic models for Ra , Rz , Ra and Rz were significant due to the values of probability value (“Prob>F”) less than 0,05. In this case, all the input laser parameters were also the significant model terms for variation of surface roughness. The values of correlation coefficient were very close to 1, which meant the selected quadratic models could give accurate prediction of surface roughness for laser treated wood. Therefore, it is of great significance to predict the surface roughness of the modified wood surface scientifically and to guide the selection of reasonable modifi cation process parameters.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83513824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-01DOI: 10.4067/s0718-221x2022000100437
M. Akkuş, Çağlar Akçay, M. Yalçın
Wood vinegar is a natural organic pesticide that is effective against plant diseases and harmful insects and is used in agriculture in particular for the improvement of plant and soil quality.In different application areas, wood vinegar provides effective protection against various harmful bacteria, fungi, and insects. Based on its demonstrated protection as a pesticide and antifungal, this study aimed to use wood vinegar as an im pregnation agent in wood materials. For this purpose, using the full-cell process, ( Pinus sylvestris and Fagus orientalis ) samples were impregnated with concentrations of 1 %,5 %, 3 % and 6% oak wood vinegar, obtained via the pyrolysis of sessile ( Quercus petraea ) wood at 350 ° C.The samples were then subjected to tests for brown-rot ( Serpula lacrymans ) and white-rot ( Trametes versicolor ) fungi, for Hylotrupes bajulus (Coleoptera: Cerambycidae) larvae, and for three different mold fungi ( Aspergillus niger Tiegh JAG-04-1003, Penicillium brevicompactum Dierckx FS-31, and Trichoderma harzianum Rifai FS-19). According to the results, the wood vinegar was found to exhibit antifungal, antimold, and larvicidal properties and consequently, could be used effectively in wood protection.
{"title":"Antifungal and larvicidal effects of wood vinegar on wood-destroying fungi and insects","authors":"M. Akkuş, Çağlar Akçay, M. Yalçın","doi":"10.4067/s0718-221x2022000100437","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100437","url":null,"abstract":"Wood vinegar is a natural organic pesticide that is effective against plant diseases and harmful insects and is used in agriculture in particular for the improvement of plant and soil quality.In different application areas, wood vinegar provides effective protection against various harmful bacteria, fungi, and insects. Based on its demonstrated protection as a pesticide and antifungal, this study aimed to use wood vinegar as an im pregnation agent in wood materials. For this purpose, using the full-cell process, ( Pinus sylvestris and Fagus orientalis ) samples were impregnated with concentrations of 1 %,5 %, 3 % and 6% oak wood vinegar, obtained via the pyrolysis of sessile ( Quercus petraea ) wood at 350 ° C.The samples were then subjected to tests for brown-rot ( Serpula lacrymans ) and white-rot ( Trametes versicolor ) fungi, for Hylotrupes bajulus (Coleoptera: Cerambycidae) larvae, and for three different mold fungi ( Aspergillus niger Tiegh JAG-04-1003, Penicillium brevicompactum Dierckx FS-31, and Trichoderma harzianum Rifai FS-19). According to the results, the wood vinegar was found to exhibit antifungal, antimold, and larvicidal properties and consequently, could be used effectively in wood protection.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83472542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-01DOI: 10.4067/s0718-221x2022000100441
J. Winandy, H. M. Barnes, J. Morrell
Southern pine lumber is often treated with preservatives, but issues related to initial kiln-drying conditions and geographic source across the wide southern pine growth range have been suspected to negatively affect subsequent permeability and treatability. These effects remain poorly understood. In this series of exploratory studies, southern pine from across part of the growing range subjected to different kiln-drying regimes was evaluated in three phases exploring the effects of geographic source and initial kiln-drying conditions on per -meability, pit structure and eventual preservative treatment of southern pine lumber. The results suggest that elevated temperatures coupled with poor humidity control at the start of the kiln drying process may negatively influence permeability and preservative penetration, but had only negligible effects on several other wood properties.
{"title":"Exploratory studies on effects of growth location and conditioning on treatability and permeability of southern pine lumber","authors":"J. Winandy, H. M. Barnes, J. Morrell","doi":"10.4067/s0718-221x2022000100441","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100441","url":null,"abstract":"Southern pine lumber is often treated with preservatives, but issues related to initial kiln-drying conditions and geographic source across the wide southern pine growth range have been suspected to negatively affect subsequent permeability and treatability. These effects remain poorly understood. In this series of exploratory studies, southern pine from across part of the growing range subjected to different kiln-drying regimes was evaluated in three phases exploring the effects of geographic source and initial kiln-drying conditions on per -meability, pit structure and eventual preservative treatment of southern pine lumber. The results suggest that elevated temperatures coupled with poor humidity control at the start of the kiln drying process may negatively influence permeability and preservative penetration, but had only negligible effects on several other wood properties.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76106055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-01DOI: 10.4067/s0718-221x2022000100439
Peter Niemz, Jacques Michel Njankouo, Marco Torres, E. Bachtiar
The sorption isotherms during adsorption and desorption of 25 wood species from Cameroon (included 3 species from plantation in Togo) were determined. In addition, the chemical compositions of these wood species were tested. The equilibrium moisture contents in a normal climate varied between 10,55 % and 15,6 %. A clear influence of the proportion of extractives can be seen. The maximum differences between adsorption and desorption varied between 2,3 % and 3,6 %. proportion of extractives. The total proportion of extractives varies from 3,3 % for ebiara to 20,3 % for doussie the proportion of hemicelluloses and lignin also varies greatly.
{"title":"Investigations on the sorption behaviour of selected wood species from Cameroon","authors":"Peter Niemz, Jacques Michel Njankouo, Marco Torres, E. Bachtiar","doi":"10.4067/s0718-221x2022000100439","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100439","url":null,"abstract":"The sorption isotherms during adsorption and desorption of 25 wood species from Cameroon (included 3 species from plantation in Togo) were determined. In addition, the chemical compositions of these wood species were tested. The equilibrium moisture contents in a normal climate varied between 10,55 % and 15,6 %. A clear influence of the proportion of extractives can be seen. The maximum differences between adsorption and desorption varied between 2,3 % and 3,6 %. proportion of extractives. The total proportion of extractives varies from 3,3 % for ebiara to 20,3 % for doussie the proportion of hemicelluloses and lignin also varies greatly.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77603400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-01DOI: 10.4067/s0718-221x2022000100436
Mehmet Yüksel, Halil Kılıç, T. Kuşkun, Ali Kasal
The objective of this study was to develop predictive expressions for estimating the withdrawal force capacity of various size of beech ( Fagus orientalis ) dowels from medium density fiberboard (MDF) and parti cleboard (PB). Furthermore, effects of the base material type, dowel diameter, dowel penetration and adhesive type on withdrawal force capacity were investigated. Polyurethane (PU), polyvinyl acetate based D2, and polyvinyl acetate (PVA) adhesives were utilized for gluing of dowels. A total of 540 specimens were prepared for edge and face withdrawal force capacity tests including two material types (MDF, PB), three dowel diameters (6 mm, 8 mm, 10 mm), three dowel penetration depths (15 mm, 20 mm, 25 mm for edge, 6 mm, 9 mm, 12 mm for face), three adhesive types and five replications for each group. Specimens were tested under static withdrawal forces. Based on results of tests, predictive expressions that allow furniture engineers to es timate edge and face dowel withdrawal force capacity as a function of dowel diameter and dowel penetration were developed. Calculations showed that the expressions developed provided reasonable estimates for withdrawal force capacity of dowels. As a result of statistical analyses, material type, dowel diameter, dowel pene -tration, adhesive type and their four-way interaction have significantly affected the withdrawal force capacity of dowels. Test results also indicated that PU adhesive and MDF ranked the highest withdrawal force capacity among the adhesive and material types. Increasing either dowel diameter or penetration tended to have a positive effect on withdrawal force capacity. Dowel diameter was found to have a higher effect on withdrawal force capacity than dowel penetration. orientalis ), bonded parallel and vertical to the surface of MDF and PB with polyvinylacetate (PVAc) and Polyurethane (PU) adhesives. They obtained the highest withdrawal strength in beech dowels bonded ver-tically with PVAc adhesive to the surface of MDF at 7,91 MPa. Uysal and Kurt (2007) investigated the effects of edge banding thickness, dowel dimension, type of material and type of adhesive used for edge banding on the withdrawal strength of dowel. Results showed that the highest withdrawal strength (7,019 MPa) was obtained in beech dowels with 6 mm diameter for MDF with solid wood edge banding of white oak with 10 mm thickness bonded with the hot-melt adhesive. In a similar study carried out by Yapıcı et al . (2011), it was determined that the edge banding thickness, dimension of dowels, material type. and adhesive type used for edge banding have significant effect on withdrawal strength of dowels. They obtained the highest withdrawal strength in beech dowels (6,68 MPa) with 8 mm diameter for MDF with 5 mm thickness of solid wood edge banding of bonded beech with PU adhesive. Kurt et al . (2009), determined the withdrawal strengths of 6 mm, 8 mm, 10 mm diameter beech dowels with respect to edge of MDF or PB edged with 5
{"title":"Predictive expressions for withdrawal force capacity of various size of dowels from particleboard and medium density fiberboard","authors":"Mehmet Yüksel, Halil Kılıç, T. Kuşkun, Ali Kasal","doi":"10.4067/s0718-221x2022000100436","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100436","url":null,"abstract":"The objective of this study was to develop predictive expressions for estimating the withdrawal force capacity of various size of beech ( Fagus orientalis ) dowels from medium density fiberboard (MDF) and parti cleboard (PB). Furthermore, effects of the base material type, dowel diameter, dowel penetration and adhesive type on withdrawal force capacity were investigated. Polyurethane (PU), polyvinyl acetate based D2, and polyvinyl acetate (PVA) adhesives were utilized for gluing of dowels. A total of 540 specimens were prepared for edge and face withdrawal force capacity tests including two material types (MDF, PB), three dowel diameters (6 mm, 8 mm, 10 mm), three dowel penetration depths (15 mm, 20 mm, 25 mm for edge, 6 mm, 9 mm, 12 mm for face), three adhesive types and five replications for each group. Specimens were tested under static withdrawal forces. Based on results of tests, predictive expressions that allow furniture engineers to es timate edge and face dowel withdrawal force capacity as a function of dowel diameter and dowel penetration were developed. Calculations showed that the expressions developed provided reasonable estimates for withdrawal force capacity of dowels. As a result of statistical analyses, material type, dowel diameter, dowel pene -tration, adhesive type and their four-way interaction have significantly affected the withdrawal force capacity of dowels. Test results also indicated that PU adhesive and MDF ranked the highest withdrawal force capacity among the adhesive and material types. Increasing either dowel diameter or penetration tended to have a positive effect on withdrawal force capacity. Dowel diameter was found to have a higher effect on withdrawal force capacity than dowel penetration. orientalis ), bonded parallel and vertical to the surface of MDF and PB with polyvinylacetate (PVAc) and Polyurethane (PU) adhesives. They obtained the highest withdrawal strength in beech dowels bonded ver-tically with PVAc adhesive to the surface of MDF at 7,91 MPa. Uysal and Kurt (2007) investigated the effects of edge banding thickness, dowel dimension, type of material and type of adhesive used for edge banding on the withdrawal strength of dowel. Results showed that the highest withdrawal strength (7,019 MPa) was obtained in beech dowels with 6 mm diameter for MDF with solid wood edge banding of white oak with 10 mm thickness bonded with the hot-melt adhesive. In a similar study carried out by Yapıcı et al . (2011), it was determined that the edge banding thickness, dimension of dowels, material type. and adhesive type used for edge banding have significant effect on withdrawal strength of dowels. They obtained the highest withdrawal strength in beech dowels (6,68 MPa) with 8 mm diameter for MDF with 5 mm thickness of solid wood edge banding of bonded beech with PU adhesive. Kurt et al . (2009), determined the withdrawal strengths of 6 mm, 8 mm, 10 mm diameter beech dowels with respect to edge of MDF or PB edged with 5","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89495267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-01DOI: 10.4067/s0718-221x2022000100435
M. Aquino, M. Rugolo, Gerardo Robledo, F. Kuhar
Mycelium composites consist of particulate lignocellulosic materials, e.g., sawdust from the timber industry structured as a solid matrix resulting from the mycelial growth. Many protocols have been proposed based on different strains and substrates. However, the influence of intrinsic elements, such as the structure of the hyphal system on the main parameters required by the industry still needs to be researched. The main goal of this work is to assess the performance of five Patagonian lignocellulolytic fungal species for producing mycelium composites. Strains of these species were studied in order to assess the relation between basidiome hyphal structure and the hyphal structure of mycelium-based materials. Comparisons of the hardness in the Janka scale were performed with commercial expanded polystyrene. Composites resulting from the growth of Pleurotus ostreatus , Nothophellinus andinopatagonicus and Funalia trogii successfully formed composites, showing a lower quality than Ganoderma austral. Ryvardenia cretacea in turn completely failed to colonize the substrate. The material resulting from the growth of Ganoderma australe on pine sawdust (a substrate chosen based on its local availability) is proposed as a good substitute with improved resistance. hyphal system, patagonia strains, sawdust substrate.
{"title":"Evaluation of mycelium composite materials produced by five Patagonian fungal species","authors":"M. Aquino, M. Rugolo, Gerardo Robledo, F. Kuhar","doi":"10.4067/s0718-221x2022000100435","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100435","url":null,"abstract":"Mycelium composites consist of particulate lignocellulosic materials, e.g., sawdust from the timber industry structured as a solid matrix resulting from the mycelial growth. Many protocols have been proposed based on different strains and substrates. However, the influence of intrinsic elements, such as the structure of the hyphal system on the main parameters required by the industry still needs to be researched. The main goal of this work is to assess the performance of five Patagonian lignocellulolytic fungal species for producing mycelium composites. Strains of these species were studied in order to assess the relation between basidiome hyphal structure and the hyphal structure of mycelium-based materials. Comparisons of the hardness in the Janka scale were performed with commercial expanded polystyrene. Composites resulting from the growth of Pleurotus ostreatus , Nothophellinus andinopatagonicus and Funalia trogii successfully formed composites, showing a lower quality than Ganoderma austral. Ryvardenia cretacea in turn completely failed to colonize the substrate. The material resulting from the growth of Ganoderma australe on pine sawdust (a substrate chosen based on its local availability) is proposed as a good substitute with improved resistance. hyphal system, patagonia strains, sawdust substrate.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90899490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-01DOI: 10.4067/s0718-221x2022000100434
Ritesh Kumar, Jayshree Gunjal, S. Chauhan
Wood fiber filled high density polyethylene composites (WPCs) were prepared using twin screw extruder and maleated polyethylene as a coupling agent. Bamboo fibers were initially treated with alkali (NaOH), boric acid - borax (Ba-Bx) and borax (Bx). The treated and untreated fibers were used in combination with ammo nium polyphosphate (APP) to investigate their synergistic effects on thermal stability, flame retardancy and mechanical properties. Alkali pretreatment (5 % NaOH) of fibers showed significant improvement in perfor mance of APP by increasing thermal stability in WPCs. The derivative thermogravimetric (DTG) results indi cate significance of Ba-Bx in promoting char induction at lower temperatures (340 ºC) and thereby, improved the thermal stability in WPCs. Flammability decreased with addition of flame retardant additives. As compared to pure WPCs, composites containing APP 10 % / Ba-Bx 5 % exhibited maximum reduction in average heat release rate (HRR) by 69 %, peak heat release rate (PHRR) by 59 %, total heat released rate (THR) by 48 % and also increased time to ignition (TTI) by 62 %. However, no significant difference was found among the combinations i.e., APP with or without compounds towards reducing the flammability of WPCs. The strength properties also reduced significantly when boron compounds were added along with APP. In general, APP alone (15 %) is enough for imparting thermal stability and flame retardancy in WPCs.
{"title":"Effect of borax-boric acid and ammonium polyphosphate on flame retardancy of natural fiber polyethylene composites","authors":"Ritesh Kumar, Jayshree Gunjal, S. Chauhan","doi":"10.4067/s0718-221x2022000100434","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100434","url":null,"abstract":"Wood fiber filled high density polyethylene composites (WPCs) were prepared using twin screw extruder and maleated polyethylene as a coupling agent. Bamboo fibers were initially treated with alkali (NaOH), boric acid - borax (Ba-Bx) and borax (Bx). The treated and untreated fibers were used in combination with ammo nium polyphosphate (APP) to investigate their synergistic effects on thermal stability, flame retardancy and mechanical properties. Alkali pretreatment (5 % NaOH) of fibers showed significant improvement in perfor mance of APP by increasing thermal stability in WPCs. The derivative thermogravimetric (DTG) results indi cate significance of Ba-Bx in promoting char induction at lower temperatures (340 ºC) and thereby, improved the thermal stability in WPCs. Flammability decreased with addition of flame retardant additives. As compared to pure WPCs, composites containing APP 10 % / Ba-Bx 5 % exhibited maximum reduction in average heat release rate (HRR) by 69 %, peak heat release rate (PHRR) by 59 %, total heat released rate (THR) by 48 % and also increased time to ignition (TTI) by 62 %. However, no significant difference was found among the combinations i.e., APP with or without compounds towards reducing the flammability of WPCs. The strength properties also reduced significantly when boron compounds were added along with APP. In general, APP alone (15 %) is enough for imparting thermal stability and flame retardancy in WPCs.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89310152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-01DOI: 10.4067/s0718-221x2022000100429
Alia Syahirah Yusoh, F. A. Sabaruddin, Paridah Md Tahir, Seng Hua Lee, M. K. A. Uyup, H. Husain, A. Ghani, S. Hiziroglu
The aim of this study was to evaluate the effect of heat treatment on surface roughness, shear strength and hardness of two tropical wood species, namely batai ( Paraserainthes falcataria ) and sesendok ( Endospermum malaccensis ). Samples were exposed to temperature levels of 120 ºC and 180 ºC for 3 h and 6 h. The surface quality of the control and heat-treated samples were determined using a stylus technique. Hardness and shear strength of the samples were evaluated using Janka hardness and block-shear test, respectively. The results reveal that the surface roughness of batai improved 3 % for 80-grit and 5 % for 180-grit samples while surface roughness of sesendok improved 7 % and 10 % for 80-grit and hardness. Overall, the hardness and shear of both species were adversely influenced by heat exposure.
{"title":"Shear strength and hardness of two tropical wood species as function of heat treatment","authors":"Alia Syahirah Yusoh, F. A. Sabaruddin, Paridah Md Tahir, Seng Hua Lee, M. K. A. Uyup, H. Husain, A. Ghani, S. Hiziroglu","doi":"10.4067/s0718-221x2022000100429","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100429","url":null,"abstract":"The aim of this study was to evaluate the effect of heat treatment on surface roughness, shear strength and hardness of two tropical wood species, namely batai ( Paraserainthes falcataria ) and sesendok ( Endospermum malaccensis ). Samples were exposed to temperature levels of 120 ºC and 180 ºC for 3 h and 6 h. The surface quality of the control and heat-treated samples were determined using a stylus technique. Hardness and shear strength of the samples were evaluated using Janka hardness and block-shear test, respectively. The results reveal that the surface roughness of batai improved 3 % for 80-grit and 5 % for 180-grit samples while surface roughness of sesendok improved 7 % and 10 % for 80-grit and hardness. Overall, the hardness and shear of both species were adversely influenced by heat exposure.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86316935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-01DOI: 10.4067/s0718-221x2022000100430
Flávia Maria Silva Brito, G. Bortoletto, J. Paes
This study aimed to evaluate the chemical composition of wood particles (control and treated), and the effects of thermal modification and adhesive levels on the wettability and biological resistance of particleboards made of sugarcane residue and bamboo (Dendrocalamus asper). Therefore, 75% bamboo particles and 25% sugarcane residue (bagasse) were used for producing the particleboards. The particles were treated at 220 °C for 3h35min. Urea formaldehyde (UF) adhesive was used in three solid contents (10%, 12% and 14%) based on the dry mass of the particles. The mat was cold pre-consolidated (pressure of 0,5 MPa for 5 min) and after hot consolidated (3,45 MPa, 180 oC, 10 min). Water and ethylene glycol and two measurement times were used to measure the contact angle. Gloeophyllum trabeum and Rhodonia placenta (brown rot) and Trametes versicolor (white rot) fungi were used for the biological resistance test. There was a change in the chemical composition of the treated particles such as a reduction in the levels of lignin (bagasse and bamboo), total extracts and holocellulose (bagasse). The thermal treatment increased the final contact angles obtained with water. The particleboard surfaces were classified as non-wettable and partially wettable to the tested solvents. The thermal treatment provided biological resistance improvements in the particleboards to the tested fungi, being classified as very resistant to Rhodonia placenta, resistant to very resistant to Gloeophyllum trabeum, and moderate to resistant to Trametes versicolor.
{"title":"Wettability and decay of particleboards manufactured with thermally treated sugarcane residue and bamboo (Dendrocalamus asper) particles","authors":"Flávia Maria Silva Brito, G. Bortoletto, J. Paes","doi":"10.4067/s0718-221x2022000100430","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100430","url":null,"abstract":"This study aimed to evaluate the chemical composition of wood particles (control and treated), and the effects of thermal modification and adhesive levels on the wettability and biological resistance of particleboards made of sugarcane residue and bamboo (Dendrocalamus asper). Therefore, 75% bamboo particles and 25% sugarcane residue (bagasse) were used for producing the particleboards. The particles were treated at 220 °C for 3h35min. Urea formaldehyde (UF) adhesive was used in three solid contents (10%, 12% and 14%) based on the dry mass of the particles. The mat was cold pre-consolidated (pressure of 0,5 MPa for 5 min) and after hot consolidated (3,45 MPa, 180 oC, 10 min). Water and ethylene glycol and two measurement times were used to measure the contact angle. Gloeophyllum trabeum and Rhodonia placenta (brown rot) and Trametes versicolor (white rot) fungi were used for the biological resistance test. There was a change in the chemical composition of the treated particles such as a reduction in the levels of lignin (bagasse and bamboo), total extracts and holocellulose (bagasse). The thermal treatment increased the final contact angles obtained with water. The particleboard surfaces were classified as non-wettable and partially wettable to the tested solvents. The thermal treatment provided biological resistance improvements in the particleboards to the tested fungi, being classified as very resistant to Rhodonia placenta, resistant to very resistant to Gloeophyllum trabeum, and moderate to resistant to Trametes versicolor.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73219440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-01DOI: 10.4067/s0718-221x2022000100431
E. Güray, Erkan Ceylan, Ali Kasal
Weight-strength optimization of wooden household chairs was performed based on the member section size in this study. Member section sizes of the Scotch pine ( Pinus sylvestris ) and Oriental beech ( Fagus orientalis ) chairs were optimized and resulting re-manufactured optimized chairs were tested under the cyclic “front to back”, “back to front” and “backrest” loads according to American Library Association (ALA) specification. Finite element method (FEM) and MATLAB nonlinear programming were utilized for the opti -mization. Firstly, the internal forces and moments acting on each member were analyzed by FEM in order to obtain the maximum critical stresses in each type of member; then, optimized cross-sectional sizes of the members were determined by Gradient Descent method, and all constraints were treated with Logarithmic Barrier Functioning. As a result, the minimum section sizes of members were determined, and cyclic performance tests were performed to determine whether the optimized chairs were strong enough to carry the acceptable loads. According to the results, member section size of both beech and pine chairs could be significantly reduced. The reduction was 32 % in the total weight and volume for beech chairs while 16 % for pine chairs without sacrificing the performance required for domestic usage by ALA. In conclusion, the method used is suitable for the optimization of furniture frames, making it lighter and reducing the material costs.
{"title":"Weight-strength optimization of wooden household chairs based on member section size","authors":"E. Güray, Erkan Ceylan, Ali Kasal","doi":"10.4067/s0718-221x2022000100431","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100431","url":null,"abstract":"Weight-strength optimization of wooden household chairs was performed based on the member section size in this study. Member section sizes of the Scotch pine ( Pinus sylvestris ) and Oriental beech ( Fagus orientalis ) chairs were optimized and resulting re-manufactured optimized chairs were tested under the cyclic “front to back”, “back to front” and “backrest” loads according to American Library Association (ALA) specification. Finite element method (FEM) and MATLAB nonlinear programming were utilized for the opti -mization. Firstly, the internal forces and moments acting on each member were analyzed by FEM in order to obtain the maximum critical stresses in each type of member; then, optimized cross-sectional sizes of the members were determined by Gradient Descent method, and all constraints were treated with Logarithmic Barrier Functioning. As a result, the minimum section sizes of members were determined, and cyclic performance tests were performed to determine whether the optimized chairs were strong enough to carry the acceptable loads. According to the results, member section size of both beech and pine chairs could be significantly reduced. The reduction was 32 % in the total weight and volume for beech chairs while 16 % for pine chairs without sacrificing the performance required for domestic usage by ALA. In conclusion, the method used is suitable for the optimization of furniture frames, making it lighter and reducing the material costs.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86633839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：