Pub Date : 2023-03-01DOI: 10.4067/s0718-221x2023000100418
Elif Topaloglu
Identifying wood species of each wood element of a historical wooden building and investigating the changes in wood properties due to exposed outdoors during its service life are important prerequisites for the maintenance and renovation of historical wooden buildings. In the present study, the changes in wood properties occurring during natural aging of two facade elements taken from a traditional house, which has a service life of approximately 100 years, were investigated. Destructive tests were used for the experiments. The wood species, moisture content, wood density, water absorption rate and chemical structure of both facade elements were determined. Microscopic analysis revealed that the molding was made from the wood of Scots pine ( Pinus sylvestris ) and the window jamb was made from chestnut ( Castanea sativa ). It was found that the cellulose and lignin on the outer surface of aged woods of both facade elements were degraded according to the FTIR analysis. The moisture and density values of aged wood for both facade elements were smaller than those of recent wood. The water absorption rates of aged woods of both molding and window jamb increased with natural aging.
{"title":"Effect of natural aging on selected properties of wooden facade elements made of scots pine and chestnut","authors":"Elif Topaloglu","doi":"10.4067/s0718-221x2023000100418","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100418","url":null,"abstract":"Identifying wood species of each wood element of a historical wooden building and investigating the changes in wood properties due to exposed outdoors during its service life are important prerequisites for the maintenance and renovation of historical wooden buildings. In the present study, the changes in wood properties occurring during natural aging of two facade elements taken from a traditional house, which has a service life of approximately 100 years, were investigated. Destructive tests were used for the experiments. The wood species, moisture content, wood density, water absorption rate and chemical structure of both facade elements were determined. Microscopic analysis revealed that the molding was made from the wood of Scots pine ( Pinus sylvestris ) and the window jamb was made from chestnut ( Castanea sativa ). It was found that the cellulose and lignin on the outer surface of aged woods of both facade elements were degraded according to the FTIR analysis. The moisture and density values of aged wood for both facade elements were smaller than those of recent wood. The water absorption rates of aged woods of both molding and window jamb increased with natural aging.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"96 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81884107","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 : 2023-03-01DOI: 10.4067/s0718-221x2023000100417
A. Istek, Özgür Yiğittap, İsmail Özlüsoylu
In the production of particleboard, the chips emerging from the drying oven usually pass into the bonding process without sufficiently cooling down. Moreover, along with the effect of friction during the bonding process, the increased chip temperature boosts the consumption of resin/adhesive and affects the properties of the board. This study investigated the effect of chip temperature during the bonding process on the properties of particleboard. With this aim, the effects were determined for six different temperatures (25 °C, 30 °C, 35 °C, 40 °C, 50 °C, 55 °C) measured during the bonding of the chips. According to the results, optimum board properties were obtained from the groups in which the chip temperature measured during the bonding process was 30 °C - 40 °C. Furthermore, it was determined that chip temperatures of above 40 °C during the bonding process significantly reduced the mechanical properties .
{"title":"Effect of chip temperature during bonding on particleboard properties","authors":"A. Istek, Özgür Yiğittap, İsmail Özlüsoylu","doi":"10.4067/s0718-221x2023000100417","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100417","url":null,"abstract":"In the production of particleboard, the chips emerging from the drying oven usually pass into the bonding process without sufficiently cooling down. Moreover, along with the effect of friction during the bonding process, the increased chip temperature boosts the consumption of resin/adhesive and affects the properties of the board. This study investigated the effect of chip temperature during the bonding process on the properties of particleboard. With this aim, the effects were determined for six different temperatures (25 °C, 30 °C, 35 °C, 40 °C, 50 °C, 55 °C) measured during the bonding of the chips. According to the results, optimum board properties were obtained from the groups in which the chip temperature measured during the bonding process was 30 °C - 40 °C. Furthermore, it was determined that chip temperatures of above 40 °C during the bonding process significantly reduced the mechanical properties .","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"24 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78722991","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 : 2023-03-01DOI: 10.4067/s0718-221x2023000100413
Liao Xiaoping, Li Chunli, J. Morrell, He Haishan, Qiu Jian, Zhang Neng
Cryptomeria fortunei has been widely planted in many cities in southern China. Eventually some of this material may be utilized for timber, but there are relatively few studies of durability of this resource. There is also some question as to whether Cryptomeria fortunei is a synonym for Cryptomeria japonica or Japanese cedar (Sugi). Evaluating the durability of the Chinese resource will help ensure that the decay resistance of this urban plantation resource is properly categorized. The decay resistance of Cryptomeria fortunei wood was assessed in soil block and agar block tests against Trametes versicolor , Gloeophyllum trabeum and Rhodonia placenta . Hot water and ethanol extractive contents of the heartwood were determined on sections from various distances above ground and then FTIR spectroscopy was used to characterize the wood before and after fungal exposure. Weight losses in sapwood were consistent with the minimal decay resistance of this por-tion of the wood. Inner and outer heartwood weight losses were more variable suggesting that the heartwood of this species would be considered to be only moderately durable. Extractives were weakly correlated with decay resistance. FTIR results were more variable, although they suggested heavier attack of lignin components by the brown rot fungi. The results suggest that Cryptomeria fortunei would need to be protected from the weather unless supplemental preservative treatments were applied.
{"title":"Variations in decay resistance of Cryptomeria fortunei","authors":"Liao Xiaoping, Li Chunli, J. Morrell, He Haishan, Qiu Jian, Zhang Neng","doi":"10.4067/s0718-221x2023000100413","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100413","url":null,"abstract":"Cryptomeria fortunei has been widely planted in many cities in southern China. Eventually some of this material may be utilized for timber, but there are relatively few studies of durability of this resource. There is also some question as to whether Cryptomeria fortunei is a synonym for Cryptomeria japonica or Japanese cedar (Sugi). Evaluating the durability of the Chinese resource will help ensure that the decay resistance of this urban plantation resource is properly categorized. The decay resistance of Cryptomeria fortunei wood was assessed in soil block and agar block tests against Trametes versicolor , Gloeophyllum trabeum and Rhodonia placenta . Hot water and ethanol extractive contents of the heartwood were determined on sections from various distances above ground and then FTIR spectroscopy was used to characterize the wood before and after fungal exposure. Weight losses in sapwood were consistent with the minimal decay resistance of this por-tion of the wood. Inner and outer heartwood weight losses were more variable suggesting that the heartwood of this species would be considered to be only moderately durable. Extractives were weakly correlated with decay resistance. FTIR results were more variable, although they suggested heavier attack of lignin components by the brown rot fungi. The results suggest that Cryptomeria fortunei would need to be protected from the weather unless supplemental preservative treatments were applied.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"1 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82286339","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 : 2023-03-01DOI: 10.4067/s0718-221x2023000100416
Á. Rodríguez‐González, P. Casquero, J. A. Pereira, Ó. González‐López, M. Guerra, J. García-González, J. M. M. Pozo, A. Juan-Valdés
The cerambycid insect Xylotrechus arvicola is considered a pest that affects the wood of the grapevine ( Vitis vinifera ) in the major wine areas of the Iberian Peninsula. The larva of this insect perforates the grape - vine wood, resulting in structural and biomechanical failure of the vine plants. Vine samples from wood damaged by X. arvicola larvae were picked up from different vineyards and grape varieties. Compressive and flexural tests were performed in order to assess the mechanical behaviour of the wood samples. Total length of the cracks in wood samples (TLCWS) that appeared on the surface of the grapevine wood samples after the mechanical tests was measured. Compressive strength (CS) and flexural strength (FS) decreased with the increase of the cross-sectional area (CSA) of both branches and trunks, regardless
{"title":"Mechanical behaviour of grapevine wood affected by Xylotrechus arvicola","authors":"Á. Rodríguez‐González, P. Casquero, J. A. Pereira, Ó. González‐López, M. Guerra, J. García-González, J. M. M. Pozo, A. Juan-Valdés","doi":"10.4067/s0718-221x2023000100416","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100416","url":null,"abstract":"The cerambycid insect Xylotrechus arvicola is considered a pest that affects the wood of the grapevine ( Vitis vinifera ) in the major wine areas of the Iberian Peninsula. The larva of this insect perforates the grape - vine wood, resulting in structural and biomechanical failure of the vine plants. Vine samples from wood damaged by X. arvicola larvae were picked up from different vineyards and grape varieties. Compressive and flexural tests were performed in order to assess the mechanical behaviour of the wood samples. Total length of the cracks in wood samples (TLCWS) that appeared on the surface of the grapevine wood samples after the mechanical tests was measured. Compressive strength (CS) and flexural strength (FS) decreased with the increase of the cross-sectional area (CSA) of both branches and trunks, regardless","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"338 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84034755","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 : 2023-03-01DOI: 10.4067/s0718-221x2023000100415
N. A. Sadiku, Abdulazeez Faruq Yusuph
Bamboo biomass was pulped using organosolv methods: Acetic acid and formic acid; hydrogen peroxide and formic acid; ethanol and water and kraft process with varying concentrations of the cooking chemicals. The properties of the isolated lignin were influenced by the black liquor pH as well as the pulping method. Highest pH (12,8) was recorded for kraft at 70:30 liquor concentration while lowest pH of 2,5 was recorded for both Aceticformic (70:30) and Ethanol/water (70:30 and 60:40). There were obvious differences in the characteristic colours, shapes and sizes of the lignin samples. Bamboo kraft lignin samples formed large pieces much easier than that of Organosolv. Aceticformic (70:30) had the best filteration properties (FC) while Etha - nol/water had the poorest. Generally, kraft recorded the highest lignin yield while all the organosolv processes recorded reduced yield. Highest yield (119,25 g/L) was gotten from kraft (50:50) while Peroxyformic (60:40) had the lowest yield of 8,20 g/L. The results showed that higher liquor pH favours total dissolved solid as well as lignin precipitation. As the pH increases, total dissolved solid, yield, Klason and low molecular weight (LMW) lignin content increases while FC decreases. The Klason and LMW lignin content increased with incresing lignin yield.
{"title":"Characterisation of lignins isolated from Bamboo organosolv and kraft black liquor","authors":"N. A. Sadiku, Abdulazeez Faruq Yusuph","doi":"10.4067/s0718-221x2023000100415","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100415","url":null,"abstract":"Bamboo biomass was pulped using organosolv methods: Acetic acid and formic acid; hydrogen peroxide and formic acid; ethanol and water and kraft process with varying concentrations of the cooking chemicals. The properties of the isolated lignin were influenced by the black liquor pH as well as the pulping method. Highest pH (12,8) was recorded for kraft at 70:30 liquor concentration while lowest pH of 2,5 was recorded for both Aceticformic (70:30) and Ethanol/water (70:30 and 60:40). There were obvious differences in the characteristic colours, shapes and sizes of the lignin samples. Bamboo kraft lignin samples formed large pieces much easier than that of Organosolv. Aceticformic (70:30) had the best filteration properties (FC) while Etha - nol/water had the poorest. Generally, kraft recorded the highest lignin yield while all the organosolv processes recorded reduced yield. Highest yield (119,25 g/L) was gotten from kraft (50:50) while Peroxyformic (60:40) had the lowest yield of 8,20 g/L. The results showed that higher liquor pH favours total dissolved solid as well as lignin precipitation. As the pH increases, total dissolved solid, yield, Klason and low molecular weight (LMW) lignin content increases while FC decreases. The Klason and LMW lignin content increased with incresing lignin yield.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"38 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88277665","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 : 2023-03-01DOI: 10.4067/s0718-221x2023000100411
Arthur B. Aramburu, D. Gatto, R. Beltrame, R. Delucis
Based on most recently published studies, there is a large variability in both the mechanical properties of wood and sample sizes selected to evaluate them. This study aims to define sampling sufficiency for some mechanical properties of wood, which were bending strength, bending modulus, compressive strength, compressive modulus, hardness, and shear strength. The mechanical tests were carried out according to an American standard procedure on wood samples cut from clonal Eucalyptus planted in southern Brazil. Sampling sufficiency was determined by an intensive computational method based on resampling of original data using Monte Carlo simulations. The experimental tests data conformed to the normal distribution and most of the obtained sufficient sample sizes determined by Monte Carlo simulation were above those sample sizes used in most already published studies. Furthermore, properties related to wood stiffness presented smaller variabilities than their respective properties associated with wood strength, leading to smaller sample sizes for the former cases.
{"title":"Sampling sufficiency for mechanical properties of wood","authors":"Arthur B. Aramburu, D. Gatto, R. Beltrame, R. Delucis","doi":"10.4067/s0718-221x2023000100411","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100411","url":null,"abstract":"Based on most recently published studies, there is a large variability in both the mechanical properties of wood and sample sizes selected to evaluate them. This study aims to define sampling sufficiency for some mechanical properties of wood, which were bending strength, bending modulus, compressive strength, compressive modulus, hardness, and shear strength. The mechanical tests were carried out according to an American standard procedure on wood samples cut from clonal Eucalyptus planted in southern Brazil. Sampling sufficiency was determined by an intensive computational method based on resampling of original data using Monte Carlo simulations. The experimental tests data conformed to the normal distribution and most of the obtained sufficient sample sizes determined by Monte Carlo simulation were above those sample sizes used in most already published studies. Furthermore, properties related to wood stiffness presented smaller variabilities than their respective properties associated with wood strength, leading to smaller sample sizes for the former cases.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"4 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85590709","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 : 2023-03-01DOI: 10.4067/s0718-221x2023000100414
Fernando Rusch, É. Hillig, Erick Chagas Mustefaga, R. Trevisan, José Guilherme Prata, G. M. Miranda
Particleboard can be produced from a mixture of different lignocellulosic materials, which can be chosen depending on the density required for the panel and its applications. The aim of this study was to evaluate the mechanical properties of particleboard with bamboo, pine and mate for a new product of high density for the special applications currently served by HDF. Particles of bamboo ( Phyllostachys aurea ) finely chopped sticks of mate ( Ilex paraguariensis ) and commercial particles of southern pine ( Pinus taeda ) wood were used. These particles used 100 % by weight in the panel or in mixtures of 50 % each (three mixtures) or in a triple mixture of one third each, were glued in a drum-type rotary mixer with melamine-urea-formaldehyde (MUF) resin,
{"title":"Particleboard experimental production with bamboo, pine and mate for one product of new applications","authors":"Fernando Rusch, É. Hillig, Erick Chagas Mustefaga, R. Trevisan, José Guilherme Prata, G. M. Miranda","doi":"10.4067/s0718-221x2023000100414","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100414","url":null,"abstract":"Particleboard can be produced from a mixture of different lignocellulosic materials, which can be chosen depending on the density required for the panel and its applications. The aim of this study was to evaluate the mechanical properties of particleboard with bamboo, pine and mate for a new product of high density for the special applications currently served by HDF. Particles of bamboo ( Phyllostachys aurea ) finely chopped sticks of mate ( Ilex paraguariensis ) and commercial particles of southern pine ( Pinus taeda ) wood were used. These particles used 100 % by weight in the panel or in mixtures of 50 % each (three mixtures) or in a triple mixture of one third each, were glued in a drum-type rotary mixer with melamine-urea-formaldehyde (MUF) resin,","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"49 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77621824","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 : 2022-12-01DOI: 10.4067/s0718-221x2023000100408
A. Apsari, Takashi Tanaka
An optimum adhesive penetration is needed to provide satisfactory bonding strength at the veneer-veneer interface. The effect of veneer density and glue spreading rate on the phenol formaldehyde adhesive penetra - tion plot profile was determined. An X-ray apparatus was used to visualize the adhesive penetration of the ply - wood. The heartwood and sapwood veneer of Cryptomeria japonica with low, medium, and high veneer densi - ties were made into plywood. The glue spreading rate was applied from 75 g/m 2 to 225 g/m 2 for the heartwood plywood and up to 300 g/m 2 for the sapwood plywood (plus 75 g/m 2 at every level of glue spreading rate). An X-ray apparatus with a low tube voltage successfully visualized the adhesive penetration plot profile. Based on the half-width calculation, the adhesive penetration depth ranged from 0,3 - 0,9 mm. The mean half-width was 0,5 mm. The adhesive concentration increased with increasing glue spreading rate. In contrast, it also showed that using different veneer densities and increasing glue spreading rates does not affect the half-width value as the adhesive penetrates deeper.
{"title":"Effects of glue spreading rate and veneer density on sugi (Cryptomeria japonica) plywood adhesive penetration","authors":"A. Apsari, Takashi Tanaka","doi":"10.4067/s0718-221x2023000100408","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100408","url":null,"abstract":"An optimum adhesive penetration is needed to provide satisfactory bonding strength at the veneer-veneer interface. The effect of veneer density and glue spreading rate on the phenol formaldehyde adhesive penetra - tion plot profile was determined. An X-ray apparatus was used to visualize the adhesive penetration of the ply - wood. The heartwood and sapwood veneer of Cryptomeria japonica with low, medium, and high veneer densi - ties were made into plywood. The glue spreading rate was applied from 75 g/m 2 to 225 g/m 2 for the heartwood plywood and up to 300 g/m 2 for the sapwood plywood (plus 75 g/m 2 at every level of glue spreading rate). An X-ray apparatus with a low tube voltage successfully visualized the adhesive penetration plot profile. Based on the half-width calculation, the adhesive penetration depth ranged from 0,3 - 0,9 mm. The mean half-width was 0,5 mm. The adhesive concentration increased with increasing glue spreading rate. In contrast, it also showed that using different veneer densities and increasing glue spreading rates does not affect the half-width value as the adhesive penetrates deeper.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"6 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89902056","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 : 2022-12-01DOI: 10.4067/s0718-221x2023000100407
Osman Çamlıbel
In this study, Its the influence of according to press, particleboards produced in two different press types which were multiday and continuous hot press, the thickness, density, bending strength, modulus of elasticity, internal bond, surface soundness, withdrawal of screw resistance, moisture, thickness swelling, water absorp - tion, formaldehyde emission content were researched. 18 mm x 2100 mm x 2800 mm size particleboards were manufactured on the production line which was using urea-formaldehyde (F:U;1,07 moles), and 30 % pine, 40 % oak, 20 % beech and 10 % poplar waste mixture of the wood materials. According to results of the tests performed after the multiday and continuous hot press production of the boards; thickness (0,63 %), bending strength (1,27 %), moisture content (0,47 %), thickness swelling (37 %), and water absorption (39,9 %), modu - lus of elasticity (11,35 %), internal bond (7,22 %) were increased according to multiday hot press while density (2,7 %), surface soundness (18,81 %), withdrawal of screw resistance (14 %) and formaldehyde (57,12 %) decreased. Formaldehyde content,surface soundness, withdrawal of screw resistance are the most prominent properties influenced by continuous hot press.
本文研究了在多日热压和连续热压两种不同压型下生产的刨花板的厚度、密度、抗弯强度、弹性模量、内部粘结、表面硬度、脱螺阻力、吸湿性、厚度膨胀性、吸水率、甲醛释放量等对压型的影响。18mm x 2100 mm x 2800 mm尺寸的刨花板在生产线上生产，该生产线使用脲醛(F:U;1,07摩尔)和30%的松木，40%的橡木，20%的山毛榉和10%的杨木废料混合物的木材材料。根据多日连续热压生产后的试验结果;经过多日热压处理后，材料的厚度(0.63%)、抗弯强度(1.27%)、含水率(0.47%)、厚度膨胀(37%)、吸水率(39.9%)、弹性模量(11.35%)、内部粘结(7.22%)均有所增加，而密度(2.7%)、表面健康度(18.81%)、拔螺阻力(14%)和甲醛(57.12%)均有所下降。连续热压对甲醛含量、表面稳健性、脱螺阻力等性能的影响最为显著。
{"title":"Influence of the multiday and continuous hot press on the physical, mechanical and formaldehyde emission properties of the particleboard","authors":"Osman Çamlıbel","doi":"10.4067/s0718-221x2023000100407","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100407","url":null,"abstract":"In this study, Its the influence of according to press, particleboards produced in two different press types which were multiday and continuous hot press, the thickness, density, bending strength, modulus of elasticity, internal bond, surface soundness, withdrawal of screw resistance, moisture, thickness swelling, water absorp - tion, formaldehyde emission content were researched. 18 mm x 2100 mm x 2800 mm size particleboards were manufactured on the production line which was using urea-formaldehyde (F:U;1,07 moles), and 30 % pine, 40 % oak, 20 % beech and 10 % poplar waste mixture of the wood materials. According to results of the tests performed after the multiday and continuous hot press production of the boards; thickness (0,63 %), bending strength (1,27 %), moisture content (0,47 %), thickness swelling (37 %), and water absorption (39,9 %), modu - lus of elasticity (11,35 %), internal bond (7,22 %) were increased according to multiday hot press while density (2,7 %), surface soundness (18,81 %), withdrawal of screw resistance (14 %) and formaldehyde (57,12 %) decreased. Formaldehyde content,surface soundness, withdrawal of screw resistance are the most prominent properties influenced by continuous hot press.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"32 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87943541","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 : 2022-12-01DOI: 10.4067/s0718-221x2023000100401
Szabolcs Koman
Besides the continuously increasing demand for wood, the significant increase in its price also contributes to the increasingly broader use of fast-growing wood species and cultivars. Newer variants are continue to be cross-bred as a result. In case of a new variant within a species, it is questionable how it would adapt to a particular climatic environment and the quality of wood it would yield. The characteristics of the Paulownia tomentosa (Robust4) wood obtained from Hungarian plantations of are generally identical to those of the Paulownia tomentosa . The value of the air dry density - as typically for paulownia species- are very low i.e. 273 kg/m 3 . Its strength values (compressive strength: 9,6 MPa; tensile strength: 39,3 MPa; bending strength: 41,7 MPa; modulus of elasticity: 4116 MPa; impact bending strength: 1,4 J/cm 2 ) also reach, and in some cases, exceed those of the Paulownia tomentosa (Thunb.) Steud. and the Paulownia Clone in vitro 112 variant. Based on these, we can expect the same wood quality from the Robust4 version as from the other paulownia variants.
{"title":"Quality characteristics of the selected variant of Paulownia tomentosa (Robust4) wood cultivated in Hungary","authors":"Szabolcs Koman","doi":"10.4067/s0718-221x2023000100401","DOIUrl":"https://doi.org/10.4067/s0718-221x2023000100401","url":null,"abstract":"Besides the continuously increasing demand for wood, the significant increase in its price also contributes to the increasingly broader use of fast-growing wood species and cultivars. Newer variants are continue to be cross-bred as a result. In case of a new variant within a species, it is questionable how it would adapt to a particular climatic environment and the quality of wood it would yield. The characteristics of the Paulownia tomentosa (Robust4) wood obtained from Hungarian plantations of are generally identical to those of the Paulownia tomentosa . The value of the air dry density - as typically for paulownia species- are very low i.e. 273 kg/m 3 . Its strength values (compressive strength: 9,6 MPa; tensile strength: 39,3 MPa; bending strength: 41,7 MPa; modulus of elasticity: 4116 MPa; impact bending strength: 1,4 J/cm 2 ) also reach, and in some cases, exceed those of the Paulownia tomentosa (Thunb.) Steud. and the Paulownia Clone in vitro 112 variant. Based on these, we can expect the same wood quality from the Robust4 version as from the other paulownia variants.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"62 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90201866","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}
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