Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.908918
Honghai Liu, Xiaokai Zhang, Jing-Wen Zhang
Wood collapse is a major defect for their applications in solid wood production. Supercritical CO2(ScCO2) dewatering can quickly remove water in wood and effectively reduce the capillary tension leading to collapse of wood structure. In this study, Eucalyptus exsertaF.V. Muellwoodwas dewatered using ScCO2at 35,45,55°Cand 15,20,25 MPa, separately. The dewatering characteristics and wood deformationwere statistically analyzed and compared after dewatering. The results show that the dewatering rateof ScCO2isaffected by moisture content (MC)of wood, showing the higher the MC, the faster the dewatering. Itisalso affected significantly by pressure, indicating increased dewatering ratewith thepressure. The effect of temperature on dewatering rate is not apparent as the pressure is less than 25MPa, but it becomes significantat 25MPacondition, showing an increased dewatering rate with temperature. In this experiment, the greatest dewatering rate was 19.8%·h-1at 55°Cand 25MPa. The transversal shrinkage of all specimens after 5 cycles dewatering waslower than1.5%, indicating the ScCO2dewatering could effectively inhibit collapse of eucalyptus wood structure. Thetransversal shrinkage decreases with the pressure, and is not affected significantly by temperature.
{"title":"STUDY OF DEWATERING CHARACTERISTICS OF EUCALYPTUS WOOD BY SUPERCRITICAL CO2","authors":"Honghai Liu, Xiaokai Zhang, Jing-Wen Zhang","doi":"10.37763/wr.1336-4561/67.6.908918","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.908918","url":null,"abstract":"Wood collapse is a major defect for their applications in solid wood production. Supercritical CO2(ScCO2) dewatering can quickly remove water in wood and effectively reduce the capillary tension leading to collapse of wood structure. In this study, Eucalyptus exsertaF.V. Muellwoodwas dewatered using ScCO2at 35,45,55°Cand 15,20,25 MPa, separately. The dewatering characteristics and wood deformationwere statistically analyzed and compared after dewatering. The results show that the dewatering rateof ScCO2isaffected by moisture content (MC)of wood, showing the higher the MC, the faster the dewatering. Itisalso affected significantly by pressure, indicating increased dewatering ratewith thepressure. The effect of temperature on dewatering rate is not apparent as the pressure is less than 25MPa, but it becomes significantat 25MPacondition, showing an increased dewatering rate with temperature. In this experiment, the greatest dewatering rate was 19.8%·h-1at 55°Cand 25MPa. The transversal shrinkage of all specimens after 5 cycles dewatering waslower than1.5%, indicating the ScCO2dewatering could effectively inhibit collapse of eucalyptus wood structure. Thetransversal shrinkage decreases with the pressure, and is not affected significantly by temperature.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126739670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.10171031
J. Malik, Erlina NURUL AINI, Deazy RACHMI TRISATYA, S. Suhartana, I. Wahyudi, S. Augustina
In this study, sandwich panels made from oil palm lumber, sengon, and gmelina wood were impregnated with a boron-alum solution to improve their water andtermite resistance. Waterresistance testing was evaluated using a thickness swelling test following the method in SNI03-2105. The sandwich panelwasalso tested for its durability against dry wood termites,according to SNI 01-7207. Theweight loss, mortality,and attack degree were used as theparametersfor evaluating termite durability. The results showedthat the treatment with aboron-alum solution can increase the stability, water resistance, and weight loss properties up to 73%, 41%, and 100%, respectively. The best properties of the sandwich panel were obtained by the sengon-isocyanate panel with 8% boric acid-borax and 5% alum treatment which has thickness swelling of 2.37%, water absorptionof 49.04%, weight loss of 0.0124%, termite mortality of100%,and attack degree of 0.
{"title":"DIMENSIONAL STABILITY AND DURABILITY OF HYBRID SANDWICH PANEL MADE FROM OIL PALM LUMBER, SENGON AND GMELINA WITH BORON-ALUM IMPREGNATION","authors":"J. Malik, Erlina NURUL AINI, Deazy RACHMI TRISATYA, S. Suhartana, I. Wahyudi, S. Augustina","doi":"10.37763/wr.1336-4561/67.6.10171031","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.10171031","url":null,"abstract":"In this study, sandwich panels made from oil palm lumber, sengon, and gmelina wood were impregnated with a boron-alum solution to improve their water andtermite resistance. Waterresistance testing was evaluated using a thickness swelling test following the method in SNI03-2105. The sandwich panelwasalso tested for its durability against dry wood termites,according to SNI 01-7207. Theweight loss, mortality,and attack degree were used as theparametersfor evaluating termite durability. The results showedthat the treatment with aboron-alum solution can increase the stability, water resistance, and weight loss properties up to 73%, 41%, and 100%, respectively. The best properties of the sandwich panel were obtained by the sengon-isocyanate panel with 8% boric acid-borax and 5% alum treatment which has thickness swelling of 2.37%, water absorptionof 49.04%, weight loss of 0.0124%, termite mortality of100%,and attack degree of 0.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121752399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.10051016
Matúš Neusch, J. Sandanus, Klara Freudenberger
The paper deals with theoretical and experimental research of the timber connections using modern timber connectors Rothoblaas Alumidi. These connectors allow for semi-rigid behaviourof the connections. The paper describes the theoretical background of semi-rigid connections, explains themethods used in the numerical analysis and the design of test connections. Thethesis continues with the experimental verification of the designed specimens. Theexperimental results are compared with the numerical analysis. The findings obtained from theexperiment and recommendations for practice are summarized in the conclusion.
{"title":"EXPERIMENTAL VERIFICATION OF THE MODERN SEMI-RIGID TIMBER CONNECTIONS","authors":"Matúš Neusch, J. Sandanus, Klara Freudenberger","doi":"10.37763/wr.1336-4561/67.6.10051016","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.10051016","url":null,"abstract":"The paper deals with theoretical and experimental research of the timber connections using modern timber connectors Rothoblaas Alumidi. These connectors allow for semi-rigid behaviourof the connections. The paper describes the theoretical background of semi-rigid connections, explains themethods used in the numerical analysis and the design of test connections. Thethesis continues with the experimental verification of the designed specimens. Theexperimental results are compared with the numerical analysis. The findings obtained from theexperiment and recommendations for practice are summarized in the conclusion.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"194 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124319214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.919928
Endre Magoss, R. Rozs, S. Tatai
The main aim of this study is to define the usability of the confocal scanning optical microscope (CSOM) to evaluate the wood surface roughness. Therefore, systematic investigation was carried out to define the influences of CSOM on the acquisition of 2D surface roughness parameters. Mahr Perthometer was applied to get reference data to estimatetheapplicability of the CSOM. Because wood roughness parameters measured with stylus and optical methods are not always comparable a calibration method was conducted on a metal calibration etalon. After the calibration process, the roughness profiles taken with the optical and stylus units were much closer to each other and only the optical Rpkparameter was definitely higher due to artificial peaks generated by the optical system. In order to eliminate this measuringfailure, the morphological filter option of the optical apparatus may be activated. Thesurface roughness parameters were measured on planed Scotch pine samples. The planed surface plains were produced with 0.2 mm parallel offset to investigate thestructural influence of the single cutting plains. The obtained results show that the average values for Ra, Rq, Rz, Rk, and Rvkare close to each other for both measuring systems, only theoptically measured Rpkvalues must be corrected. The standard deviations, however, are systematically slightly higher for optical system. This may be explained by the higher resolution of the optical system giving more fine profile details. The earlier developed and introduced dimensionless quantities, such as Abbott ratio, are also fully comparable for both systems provided that the optically measured Rpkvalues are also correct.
{"title":"EVALUATION OF WOOD SURFACE ROUGHNESS BY CONFOCAL MICROSCOPY","authors":"Endre Magoss, R. Rozs, S. Tatai","doi":"10.37763/wr.1336-4561/67.6.919928","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.919928","url":null,"abstract":"The main aim of this study is to define the usability of the confocal scanning optical microscope (CSOM) to evaluate the wood surface roughness. Therefore, systematic investigation was carried out to define the influences of CSOM on the acquisition of 2D surface roughness parameters. Mahr Perthometer was applied to get reference data to estimatetheapplicability of the CSOM. Because wood roughness parameters measured with stylus and optical methods are not always comparable a calibration method was conducted on a metal calibration etalon. After the calibration process, the roughness profiles taken with the optical and stylus units were much closer to each other and only the optical Rpkparameter was definitely higher due to artificial peaks generated by the optical system. In order to eliminate this measuringfailure, the morphological filter option of the optical apparatus may be activated. Thesurface roughness parameters were measured on planed Scotch pine samples. The planed surface plains were produced with 0.2 mm parallel offset to investigate thestructural influence of the single cutting plains. The obtained results show that the average values for Ra, Rq, Rz, Rk, and Rvkare close to each other for both measuring systems, only theoptically measured Rpkvalues must be corrected. The standard deviations, however, are systematically slightly higher for optical system. This may be explained by the higher resolution of the optical system giving more fine profile details. The earlier developed and introduced dimensionless quantities, such as Abbott ratio, are also fully comparable for both systems provided that the optically measured Rpkvalues are also correct.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"2000 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125731255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.10461055
I. Mezghani
In this study, the effects of exotic and native shrubs Acacia salicinaand Retama raetamon understory vegetation and soil properties were assessed. Two sub-habitats, acanopied and anun-canopied sub-habitat (open grassland), were distinguished for each shrub species. Soil moisture was measured in both sub-habitats at 10 cm depth, and soil samples collected from theupper 10 cm soil, excluding litter and stones. Aboveground biomass, species density and species richness were also estimated. The soil organic matter, total N and extractable P were significantly higher under shrubs than open areas at all soil water contents. Soil water content did not differ significantly between studied shrubs. Aboveground biomass, species richness and the density of perennial species were significantly higher under shrub canopiesthan open areas. Among the two studied shrubs species, Retama raetamdisplayed the strongest positive effect, but without significant differences, on the understory vegetation. From this perspective, exotic shrubs can be regarded as a powerful and promising candidate that can be invested in not only theelaboration of multiple restoration programs but also in the generation of islands of resources.
{"title":"USING EXOTIC SHRUBS AS A RESTORATION TOOL IN TUNISIAN ARID AREAS: EFFECTS ON UNDERSTOREY VEGETATION AND SOIL NUTRIENTS","authors":"I. Mezghani","doi":"10.37763/wr.1336-4561/67.6.10461055","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.10461055","url":null,"abstract":"In this study, the effects of exotic and native shrubs Acacia salicinaand Retama raetamon understory vegetation and soil properties were assessed. Two sub-habitats, acanopied and anun-canopied sub-habitat (open grassland), were distinguished for each shrub species. Soil moisture was measured in both sub-habitats at 10 cm depth, and soil samples collected from theupper 10 cm soil, excluding litter and stones. Aboveground biomass, species density and species richness were also estimated. The soil organic matter, total N and extractable P were significantly higher under shrubs than open areas at all soil water contents. Soil water content did not differ significantly between studied shrubs. Aboveground biomass, species richness and the density of perennial species were significantly higher under shrub canopiesthan open areas. Among the two studied shrubs species, Retama raetamdisplayed the strongest positive effect, but without significant differences, on the understory vegetation. From this perspective, exotic shrubs can be regarded as a powerful and promising candidate that can be invested in not only theelaboration of multiple restoration programs but also in the generation of islands of resources.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133039913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.966978
G. Qin, Ming Li, Saiyin Fang, Tingting Deng, Changli Huang, Zhouling Yang, Feilong Mao, Yue Zhao
Artificial AE sources were generated on the surfaces of Ulmus pumila, Zelkova schneideriana, Cunninghamia lanceolata, and Pinus sylvestris var.mongolicaLitv. specimens. The AE transverse wave signal was decomposed into 3-layers detail signalsby wavelet decomposition and reconstructed, and it was calculated based on correlation analysis. Then thelongitudinal wave speed was calculated according to the time-difference-of-arrival (TDOA) method, and the wood dispersion phenomenon was studied. The results showed that thedispersion phenomenon of Ulmus pumilawas obvious. The propagation speed of high-frequency signal was 2.38 times that of low-frequency signal. The ratio of high and low frequency propagation speed of soft wood was 1.72 and 1.73. The dispersion degree of Zelkova schneideriana was the weakest, and the propagation speed of the high frequency was 1.25 times of the low one. The ratios of longitudinal and transverse wave speedsof the four specimens were 4.59, 4.07, 4.24 and 4.2, respectively.
{"title":"STUDY ON THE DISPERSION CHARACTERISTICS OF WOOD ACOUSTIC EMISSION SIGNAL BASED ON WAVELET DECOMPOSITION","authors":"G. Qin, Ming Li, Saiyin Fang, Tingting Deng, Changli Huang, Zhouling Yang, Feilong Mao, Yue Zhao","doi":"10.37763/wr.1336-4561/67.6.966978","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.966978","url":null,"abstract":"Artificial AE sources were generated on the surfaces of Ulmus pumila, Zelkova schneideriana, Cunninghamia lanceolata, and Pinus sylvestris var.mongolicaLitv. specimens. The AE transverse wave signal was decomposed into 3-layers detail signalsby wavelet decomposition and reconstructed, and it was calculated based on correlation analysis. Then thelongitudinal wave speed was calculated according to the time-difference-of-arrival (TDOA) method, and the wood dispersion phenomenon was studied. The results showed that thedispersion phenomenon of Ulmus pumilawas obvious. The propagation speed of high-frequency signal was 2.38 times that of low-frequency signal. The ratio of high and low frequency propagation speed of soft wood was 1.72 and 1.73. The dispersion degree of Zelkova schneideriana was the weakest, and the propagation speed of the high frequency was 1.25 times of the low one. The ratios of longitudinal and transverse wave speedsof the four specimens were 4.59, 4.07, 4.24 and 4.2, respectively.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122216277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.929940
Nduduzo Khumalo, S. Mohomane, S. Motloung, L. Koao, Malevu D. Thembinkosi, T. Motaung
The main objective of the study was to investigate the effect of mixed acid concentration on the morphology, crystallinity and thermal properties of cellulose nanocrystals (CNCs). Acid hydrolysis using mixture of sulphuric (H2SO4)acid and perchloric (HClO4) acid was used to extract CNCs from sugarcane bagasse (SCB). The properties of the raw SCB, extracted cellulose,45% H2SO4 hydrolysed CNCs,45% H2SO4/HClO4 hydrolysed CNCs, 55% H2SO4/HClO4 hydrolysed CNCs and 65% H2SO4/HClO4 hydrolysed CNCs were analysed using Fourier transmission infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Thecrystallinity of SCB was significantly increased after bleaching and acid hydrolysis. Acid hydrolysis using 55% H2SO4/HClO4 showed the highest crystallinity. The TGA results showed significant increase in thermal stability of 55% H2SO4/HClO4. The lowest thermal stability was observed with 45% H2SO4 hydrolysed CNCs. The order of thermal stability was raw SCB < extracted cellulose < 45% H2SO4hydrolysed CNCs < 65% H2SO4/HClO4 hydrolysed CNCs < 45% H2SO4/HClO4 hydrolysed CNCs < 55% H2SO4/HClO4 hydrolysed CNCs. The SEM results showed fibre breakage for 65% H2SO4/HClO4 hydrolysed CNCs. Thefibre breakage seemed to be acid concentration dependent.
{"title":"EFFECT OF H2SO4/HCLO4 MIXTURE ON PROPERTIES OF SUGARCANE BAGASSE CELLULOSE CRYSTALS","authors":"Nduduzo Khumalo, S. Mohomane, S. Motloung, L. Koao, Malevu D. Thembinkosi, T. Motaung","doi":"10.37763/wr.1336-4561/67.6.929940","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.929940","url":null,"abstract":"The main objective of the study was to investigate the effect of mixed acid concentration on the morphology, crystallinity and thermal properties of cellulose nanocrystals (CNCs). Acid hydrolysis using mixture of sulphuric (H2SO4)acid and perchloric (HClO4) acid was used to extract CNCs from sugarcane bagasse (SCB). The properties of the raw SCB, extracted cellulose,45% H2SO4 hydrolysed CNCs,45% H2SO4/HClO4 hydrolysed CNCs, 55% H2SO4/HClO4 hydrolysed CNCs and 65% H2SO4/HClO4 hydrolysed CNCs were analysed using Fourier transmission infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Thecrystallinity of SCB was significantly increased after bleaching and acid hydrolysis. Acid hydrolysis using 55% H2SO4/HClO4 showed the highest crystallinity. The TGA results showed significant increase in thermal stability of 55% H2SO4/HClO4. The lowest thermal stability was observed with 45% H2SO4 hydrolysed CNCs. The order of thermal stability was raw SCB < extracted cellulose < 45% H2SO4hydrolysed CNCs < 65% H2SO4/HClO4 hydrolysed CNCs < 45% H2SO4/HClO4 hydrolysed CNCs < 55% H2SO4/HClO4 hydrolysed CNCs. The SEM results showed fibre breakage for 65% H2SO4/HClO4 hydrolysed CNCs. Thefibre breakage seemed to be acid concentration dependent.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"106 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120968626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.10561073
Yang Wu, Jiangang Zhu, Q. Qi, Lina Cui
The softening process of wood bending has a very important influence on theperformance, forming shape, and yield of bentwood. The paper reviewed the typical softening processes in solid wood bending by analyzing the various softening mechanism and softening processes. Themain influencing factors of the softening technology on the bending properties were summarized based on the comparative analysisof the related research progress of wood softening. In view of the lack of systematic analyses of the cost and environmental factors associated with the softening process, this paper goes in detail analyzing themajor softening technologies with comprehensive comparisonof the economic and environmental advantages and disadvantages.The paper also draws light on thedevelopment trends of softening technology that can be implemented in wood industry which can hence improve the added value of wood. Under the background of green development, the authors believe that the softening technology should not only benefit theeconomic efficiency but also meet the social needs of low-carbon and environment-friendly.
{"title":"RESEARCH PROGRESS OF SOLID WOOD BENDING SOFTENING TECHNOLOGY. REVIEW","authors":"Yang Wu, Jiangang Zhu, Q. Qi, Lina Cui","doi":"10.37763/wr.1336-4561/67.6.10561073","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.10561073","url":null,"abstract":"The softening process of wood bending has a very important influence on theperformance, forming shape, and yield of bentwood. The paper reviewed the typical softening processes in solid wood bending by analyzing the various softening mechanism and softening processes. Themain influencing factors of the softening technology on the bending properties were summarized based on the comparative analysisof the related research progress of wood softening. In view of the lack of systematic analyses of the cost and environmental factors associated with the softening process, this paper goes in detail analyzing themajor softening technologies with comprehensive comparisonof the economic and environmental advantages and disadvantages.The paper also draws light on thedevelopment trends of softening technology that can be implemented in wood industry which can hence improve the added value of wood. Under the background of green development, the authors believe that the softening technology should not only benefit theeconomic efficiency but also meet the social needs of low-carbon and environment-friendly.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124407804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.941952
Chao Deng, Yang Liu, Junxiang Xu, Xiangyu Li, Mingyu Wen, Xixin Duan, Hee-Yeol Park
In this paper, ammonium phosphate polymer (APP), guanidinium phosphate urea (GUP), phosphonic acid, and a small number of additives that confer flame retardant properties were prepared as a new composite flame retardant. Cedar (Cryptomeria japonica) and hinoki (Chamaecyparis obtuse) penetrate and absorb the solution into the inner wall of the wood by vacuum pressurization, thus obtaining fire-retardant woods. The flame retardant effectsat different absorption amounts were investigated by thermogravimetric analysis and cone calorimetry.The absorption amounts of both kinds of wood above 0.095 g.cm-3and 0.085g.cm-3respectively, met the flame retardant standard ISO-5660-1: 2015. Thermogravimetric analysis showed that the fire-retardant-treated wood increased thermal stability, accelerated carbonization, and lower the decomposition temperature to below 300°C.
{"title":"FIRE RETARDANT PERFORMANCE OF SUGI AND HINOKI TREATED WITH PHOSPHORUS AND NITROGEN FIRE RETARDANT","authors":"Chao Deng, Yang Liu, Junxiang Xu, Xiangyu Li, Mingyu Wen, Xixin Duan, Hee-Yeol Park","doi":"10.37763/wr.1336-4561/67.6.941952","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.941952","url":null,"abstract":"In this paper, ammonium phosphate polymer (APP), guanidinium phosphate urea (GUP), phosphonic acid, and a small number of additives that confer flame retardant properties were prepared as a new composite flame retardant. Cedar (Cryptomeria japonica) and hinoki (Chamaecyparis obtuse) penetrate and absorb the solution into the inner wall of the wood by vacuum pressurization, thus obtaining fire-retardant woods. The flame retardant effectsat different absorption amounts were investigated by thermogravimetric analysis and cone calorimetry.The absorption amounts of both kinds of wood above 0.095 g.cm-3and 0.085g.cm-3respectively, met the flame retardant standard ISO-5660-1: 2015. Thermogravimetric analysis showed that the fire-retardant-treated wood increased thermal stability, accelerated carbonization, and lower the decomposition temperature to below 300°C.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127135999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.37763/wr.1336-4561/67.6.894907
Peter Godovčin, J. Martinka, P. Rantuch, Martina Hladová, Juraj Kopúnek, Mária Otajovičová, Mária Zuzana Bednáriková
This study deals with the investigation of impact of temperature and ultraviolet (UV) radiation on spruce wood (Picea abies(L.) H. Karst.) and fir wood (Abies albaMill.) colour changes. Samples of investigated woods species were loaded by temperatures of 110, 130, and 150°C and UV radiation (with 253.7 nm wavelength and 40 W m-2intensity) during 72, 168, 336 and 672 hours. Colour changes were evaluated in the CIE Lab colour space. Theneural network for prediction of both colour coordinates and total colour difference of spruce and fir wood was trained by data regarding exposure conditions (temperature, UV radiation and time) and by obtained results. Coefficient of determination (R2) of the neural network was above 0.99 for training, validation and testing. Average colour coordinates (±standard deviation) of the spruce and fir wood before exposure were L* = 80.08 ± 3.70,a* = 7.55 ± 2.13, b* = 21.56 ± 1.79, L* = 80.46 ± 1.91, a* = 6.84 ± 0.97, and b* = 18.90 ± 1.26, resp. Total colour differences after thermal loading were in the interval from ΔEab* = 3.76 ± 1.95 (spruce wood at 110°C) to ΔEab* = 45.37±1.46 (fir wood at 150°C). Total colour differences of both wood species exposed by UV radiation were approximately in intervals from ΔEab* = 12 to 13 (after 72 h) up to ΔEab* = 16 to 20 (after 168 to 672 h). Obtained results proven that both temperature and UV radiation have significant impact on the colour changes of the investigated woods.
{"title":"IMPACT OF TEMPERATURE AND ULTRAVIOLET RADIATION ON CHANGES OF COLOUR OF FIR AND SPRUCE WOOD","authors":"Peter Godovčin, J. Martinka, P. Rantuch, Martina Hladová, Juraj Kopúnek, Mária Otajovičová, Mária Zuzana Bednáriková","doi":"10.37763/wr.1336-4561/67.6.894907","DOIUrl":"https://doi.org/10.37763/wr.1336-4561/67.6.894907","url":null,"abstract":"This study deals with the investigation of impact of temperature and ultraviolet (UV) radiation on spruce wood (Picea abies(L.) H. Karst.) and fir wood (Abies albaMill.) colour changes. Samples of investigated woods species were loaded by temperatures of 110, 130, and 150°C and UV radiation (with 253.7 nm wavelength and 40 W m-2intensity) during 72, 168, 336 and 672 hours. Colour changes were evaluated in the CIE Lab colour space. Theneural network for prediction of both colour coordinates and total colour difference of spruce and fir wood was trained by data regarding exposure conditions (temperature, UV radiation and time) and by obtained results. Coefficient of determination (R2) of the neural network was above 0.99 for training, validation and testing. Average colour coordinates (±standard deviation) of the spruce and fir wood before exposure were L* = 80.08 ± 3.70,a* = 7.55 ± 2.13, b* = 21.56 ± 1.79, L* = 80.46 ± 1.91, a* = 6.84 ± 0.97, and b* = 18.90 ± 1.26, resp. Total colour differences after thermal loading were in the interval from ΔEab* = 3.76 ± 1.95 (spruce wood at 110°C) to ΔEab* = 45.37±1.46 (fir wood at 150°C). Total colour differences of both wood species exposed by UV radiation were approximately in intervals from ΔEab* = 12 to 13 (after 72 h) up to ΔEab* = 16 to 20 (after 168 to 672 h). Obtained results proven that both temperature and UV radiation have significant impact on the colour changes of the investigated woods.","PeriodicalId":358045,"journal":{"name":"WOOD RESEARCH 67(6) 2022","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132470936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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