Abstract In this study, representative lignin samples differing in hydroxyl content, molecular weight, linkage composition and lignin units ratio were prepared from eucalyptus wood by different isolation means and modification means: milled wood lignin (MWL), kraft lignin classified at different pH (KL), lignocresol (LC), lignoresorcinol (LR), lignopyrogallol (LP) as well as lignocresol secondary functional switched samples (LC 2ndderiv). The structure of various lignins was characterized in detail by Fourier transform infrared (FT-IR) spectroscopy, gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR). In order to eliminate the interference of other factors, bovine serum albumin (BSA) with relatively simple protein structure and different kinds of lignin and their derivatives were selected as the research objects. The adsorption/desorption behavior and mechanism between lignin samples and BSA were studied by quartz crystal microbalance with dissipation monitoring (QCM-D). The results showed that the content of phenolic hydroxyl was the main factor affecting the interaction of lignin and BSA, but in addition, the molecular size, linkages composition and the types of lignin units also had important effects on its adsorption behavior. The research will provide theoretical guidance and all-round reliable basic data for the interaction of lignin on lignocellulose hydrolysis enzymes in industrial application.
{"title":"Structural comparison of different isolated eucalyptus lignins and analysis of their interaction mechanism with bovine serum albumin solution under QCM-D","authors":"Haonan Zhang, Qi Liu, Yanchen Zhu, Zhang Feng, Hao Ren, H. Zhai","doi":"10.1515/hf-2022-0170","DOIUrl":"https://doi.org/10.1515/hf-2022-0170","url":null,"abstract":"Abstract In this study, representative lignin samples differing in hydroxyl content, molecular weight, linkage composition and lignin units ratio were prepared from eucalyptus wood by different isolation means and modification means: milled wood lignin (MWL), kraft lignin classified at different pH (KL), lignocresol (LC), lignoresorcinol (LR), lignopyrogallol (LP) as well as lignocresol secondary functional switched samples (LC 2ndderiv). The structure of various lignins was characterized in detail by Fourier transform infrared (FT-IR) spectroscopy, gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR). In order to eliminate the interference of other factors, bovine serum albumin (BSA) with relatively simple protein structure and different kinds of lignin and their derivatives were selected as the research objects. The adsorption/desorption behavior and mechanism between lignin samples and BSA were studied by quartz crystal microbalance with dissipation monitoring (QCM-D). The results showed that the content of phenolic hydroxyl was the main factor affecting the interaction of lignin and BSA, but in addition, the molecular size, linkages composition and the types of lignin units also had important effects on its adsorption behavior. The research will provide theoretical guidance and all-round reliable basic data for the interaction of lignin on lignocellulose hydrolysis enzymes in industrial application.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"77 1","pages":"437 - 452"},"PeriodicalIF":2.4,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48669656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Degradation of the mechanical properties of heat-treated wood is a significant problem that needs to be addressed. This study aimed to stabilize the mechanical strength of heat-treated spruce wood by adding gaseous ammonia during the heat treatment. Gaseous ammonia penetrates rapidly into wood and is expected to form ammonium hydroxide when combined with water in the wood. This modification strategy neutralizes the acids produced by the degradation of hemicelluloses and reduces the degradation of the wood polymer composition and cell-wall structure. The preservation of wood polymer composition and cell-wall structure increases the indentation modulus of the wood cell walls. This increases the strength of the wood cell walls, resulting in an improvement in the mechanical properties of the heat-treated wood. The heat-treated wood’s dimensional stability and equilibrium moisture content are only slightly affected by the weak alkalinity modification.
{"title":"Adding gaseous ammonia with heat treatment to improve the mechanical properties of spruce wood","authors":"Yiqin Gao, Li Li, Yao Chen","doi":"10.1515/hf-2022-0179","DOIUrl":"https://doi.org/10.1515/hf-2022-0179","url":null,"abstract":"Abstract Degradation of the mechanical properties of heat-treated wood is a significant problem that needs to be addressed. This study aimed to stabilize the mechanical strength of heat-treated spruce wood by adding gaseous ammonia during the heat treatment. Gaseous ammonia penetrates rapidly into wood and is expected to form ammonium hydroxide when combined with water in the wood. This modification strategy neutralizes the acids produced by the degradation of hemicelluloses and reduces the degradation of the wood polymer composition and cell-wall structure. The preservation of wood polymer composition and cell-wall structure increases the indentation modulus of the wood cell walls. This increases the strength of the wood cell walls, resulting in an improvement in the mechanical properties of the heat-treated wood. The heat-treated wood’s dimensional stability and equilibrium moisture content are only slightly affected by the weak alkalinity modification.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"77 1","pages":"416 - 425"},"PeriodicalIF":2.4,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41912323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lipeng Zhang, Qifang Xie, Yajie Wu, Baozhuang Zhang, Ningfen Su
Abstract Wood is mainly subjected to transverse compression in many critical parts of Chinese traditional timber structures, e.g. the mortise-tenon and Dou-Gong joints. Seismic is one of the dynamic actions faced by these structures and will cause wood to suffer higher loading speeds than quasi-static loads. The investigation of the seismic strain rates (SSRs) effects of wood under perpendicular-to-grain compression (PTGc) is important. One hundred and forty-four radial small clear wood specimens were prepared using Dahurian larch, Mongolian pine and Chinese poplar. Monotonic and cyclic compression tests were conducted under three SSRs (10−3 s−1, 10−2 s−1, and 10−1 s−1) and the quasi-static strain rate (10−4 s−1). Failure modes, stress-strain curves, yield strengths, elastic moduli and the unloading/reloading moduli were analyzed. Results indicated that the PTGc properties were highly sensitive to SSRs under both the monotonic and cyclic compression. Strengths showed higher sensitivity to SSRs than elastic moduli. The SSRs effects of wood under cyclic compression have greater variability than the monotonic counterparts. The unloading/reloading moduli shows little SSR effects statistically. Comparisons were made between the existing PTG and the parallel-to-grain test results and a fitted general expression was obtained. Furthermore, an SSR-dependent stress-strain model was proposed and verified by tests.
{"title":"Effects of seismic strain rates on the perpendicular-to-grain compression behaviour of Dahurian larch, Mongolian pine and Chinese poplar: tests and stress-strain model","authors":"Lipeng Zhang, Qifang Xie, Yajie Wu, Baozhuang Zhang, Ningfen Su","doi":"10.1515/hf-2022-0135","DOIUrl":"https://doi.org/10.1515/hf-2022-0135","url":null,"abstract":"Abstract Wood is mainly subjected to transverse compression in many critical parts of Chinese traditional timber structures, e.g. the mortise-tenon and Dou-Gong joints. Seismic is one of the dynamic actions faced by these structures and will cause wood to suffer higher loading speeds than quasi-static loads. The investigation of the seismic strain rates (SSRs) effects of wood under perpendicular-to-grain compression (PTGc) is important. One hundred and forty-four radial small clear wood specimens were prepared using Dahurian larch, Mongolian pine and Chinese poplar. Monotonic and cyclic compression tests were conducted under three SSRs (10−3 s−1, 10−2 s−1, and 10−1 s−1) and the quasi-static strain rate (10−4 s−1). Failure modes, stress-strain curves, yield strengths, elastic moduli and the unloading/reloading moduli were analyzed. Results indicated that the PTGc properties were highly sensitive to SSRs under both the monotonic and cyclic compression. Strengths showed higher sensitivity to SSRs than elastic moduli. The SSRs effects of wood under cyclic compression have greater variability than the monotonic counterparts. The unloading/reloading moduli shows little SSR effects statistically. Comparisons were made between the existing PTG and the parallel-to-grain test results and a fitted general expression was obtained. Furthermore, an SSR-dependent stress-strain model was proposed and verified by tests.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"77 1","pages":"383 - 393"},"PeriodicalIF":2.4,"publicationDate":"2023-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47817343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Scharf, A. Lemoine, Benedikt Neyses, D. Sandberg
Abstract Wood under thermo-mechanical densification behaves differently depending on the cross-sectional growth ring orientation (GRO) relative to the direction of compression. This influences the degree of cell damage, but also the shape-memory effects occurring when the compression load is released (spring-back) and when the timber is re-moistened (set-recovery). To study how the GRO influences the shape-memory effects, Scots pine specimens were separated into three distinct groups of GRO (Flat, Inclined, Hybrid) and then thermo-mechanically surface-densified. Spring-back and set-recovery were determined by thickness measurements and by digital image correlation. A GRO parallel to the densified surface, resulted in a low spring-back and a high set-recovery which were uniform over the width of the specimen. Specimens with a GRO between 15 and 45° to the densified surface showed high spring-back and low set-recovery, indicating cell-wall damage. Spring-back mainly occurred in the non-plasticised region immediately below the heated surface region and elasto-plastic rolling-shear deformation along individual growth rings occurred. The GRO of softwood subjected to thermo-mechanical densification determines if an applied load results in rolling shear-deformation or radial compression. This in turn determines where in the cross-section and when in the process the cells deform and if this deformation occurs below or above the glass-transition temperature.
{"title":"The effect of the growth ring orientation on spring-back and set-recovery in surface-densified wood","authors":"A. Scharf, A. Lemoine, Benedikt Neyses, D. Sandberg","doi":"10.1515/hf-2023-0004","DOIUrl":"https://doi.org/10.1515/hf-2023-0004","url":null,"abstract":"Abstract Wood under thermo-mechanical densification behaves differently depending on the cross-sectional growth ring orientation (GRO) relative to the direction of compression. This influences the degree of cell damage, but also the shape-memory effects occurring when the compression load is released (spring-back) and when the timber is re-moistened (set-recovery). To study how the GRO influences the shape-memory effects, Scots pine specimens were separated into three distinct groups of GRO (Flat, Inclined, Hybrid) and then thermo-mechanically surface-densified. Spring-back and set-recovery were determined by thickness measurements and by digital image correlation. A GRO parallel to the densified surface, resulted in a low spring-back and a high set-recovery which were uniform over the width of the specimen. Specimens with a GRO between 15 and 45° to the densified surface showed high spring-back and low set-recovery, indicating cell-wall damage. Spring-back mainly occurred in the non-plasticised region immediately below the heated surface region and elasto-plastic rolling-shear deformation along individual growth rings occurred. The GRO of softwood subjected to thermo-mechanical densification determines if an applied load results in rolling shear-deformation or radial compression. This in turn determines where in the cross-section and when in the process the cells deform and if this deformation occurs below or above the glass-transition temperature.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"77 1","pages":"394 - 406"},"PeriodicalIF":2.4,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47467068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Shao, Jian-fang Yu, Hui Liu, Yuhong An, Li-li Li, Zhang-jing Chen, Ximing Wang, Xiao-tao Zhang
Abstract This study aimed to evaluate the shape-memory effect (SME) of wood (Populus x beijingensis W. Y. Hsu) and identify the net-points and switches in its molecular and morphological structures. During several cycles of deformation and subsequent recovery, a high shape recovery rate and ratio were maintained. The transverse compression tests of wet and dry wood reveal that the hydrothermal coupling stimulation can considerably reduce the strength of wood. The X-ray diffraction characterization of wood under hydrothermal stimulation shows that the role of network nodes in the SME of wood is influenced by temperature. The wavenumber shifting and changes in the intensity ratio of the characteristic Fourier transform infrared peaks showed that hydrogen bonds acted as switches for the water-stimulated shape-memory behavior. By taking into account viscoelastic relaxation, a kinetic model derived from nonequilibrium thermodynamic fluctuation theory was used to describe the shape recovery process. The effects of hydration on recovery kinetics, activation, and dynamic mechanical behaviors were also studied. To explain the shape-memory mechanism of wood under hydrothermal stimulation, a hybrid-structure network model based on a single three-dimensional switch network was proposed in this study.
摘要本研究旨在评价北京杨树(Populus x beijingensis W. Y. Hsu)的形状记忆效应,并确定其分子和形态结构的网点和开关。在几次变形和随后的恢复循环中,保持了较高的形状恢复速率和比率。湿木材和干木材的横向压缩试验表明,水热耦合刺激会显著降低木材的强度。热液刺激下木材的x射线衍射表征表明,网络节点在木材SME中的作用受温度的影响。傅里叶变换红外特征峰的波数移位和强度比的变化表明,氢键对水激发的形状记忆行为起着开关作用。考虑粘弹性松弛,采用非平衡热力学涨落理论导出的动力学模型来描述形状恢复过程。研究了水化对回收动力学、活化和动态力学行为的影响。为了解释热液刺激下木材的形状记忆机制,本文提出了一种基于单一三维开关网络的混合结构网络模型。
{"title":"Wood as a hydrothermally stimulated shape-memory material: mechanisms of shape-memory effect and molecular assembly structure networks","authors":"Y. Shao, Jian-fang Yu, Hui Liu, Yuhong An, Li-li Li, Zhang-jing Chen, Ximing Wang, Xiao-tao Zhang","doi":"10.1515/hf-2022-0181","DOIUrl":"https://doi.org/10.1515/hf-2022-0181","url":null,"abstract":"Abstract This study aimed to evaluate the shape-memory effect (SME) of wood (Populus x beijingensis W. Y. Hsu) and identify the net-points and switches in its molecular and morphological structures. During several cycles of deformation and subsequent recovery, a high shape recovery rate and ratio were maintained. The transverse compression tests of wet and dry wood reveal that the hydrothermal coupling stimulation can considerably reduce the strength of wood. The X-ray diffraction characterization of wood under hydrothermal stimulation shows that the role of network nodes in the SME of wood is influenced by temperature. The wavenumber shifting and changes in the intensity ratio of the characteristic Fourier transform infrared peaks showed that hydrogen bonds acted as switches for the water-stimulated shape-memory behavior. By taking into account viscoelastic relaxation, a kinetic model derived from nonequilibrium thermodynamic fluctuation theory was used to describe the shape recovery process. The effects of hydration on recovery kinetics, activation, and dynamic mechanical behaviors were also studied. To explain the shape-memory mechanism of wood under hydrothermal stimulation, a hybrid-structure network model based on a single three-dimensional switch network was proposed in this study.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"77 1","pages":"426 - 436"},"PeriodicalIF":2.4,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48164489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Efficient and nondestructive technology for identifying wood species facilitates the transition from digital forestry to smart forestry. While near-infrared spectroscopy applied to wood identification is well documented, the detailed mechanisms for chemometrics remain unclear. In this study, twelve wood species were identified by using near-infrared spectroscopy combined with six machine learning algorithms (support vector machine, logistic regression, naïve Bayes, k-nearest neighbors, random forest, and artificial neural network). Above all, isolated forest and local outlier factor were used to detect and exclude outliers. Then feature engineering strategies were developed from three perspectives to process feature matrices: feature selection, feature extraction, and feature selection combined with feature extraction. Next, the learning curve, grid search method, and K-fold cross-validation were used to optimize the model parameters. Finally, the accuracy, operation time, and confusion matrix were used to evaluate the model performance. When the local outlier factor was used to remove outliers and principal component analysis was used to extract features, the support-vector-machine-based wood-species identification model produced the most accurate results, with 98.24% accuracy. These results offer new avenues for constructing automatic wood-identification systems.
{"title":"Building machine learning models to identify wood species based on near-infrared spectroscopy","authors":"Li Luo, Z. Xu, B. Na","doi":"10.1515/hf-2022-0122","DOIUrl":"https://doi.org/10.1515/hf-2022-0122","url":null,"abstract":"Abstract Efficient and nondestructive technology for identifying wood species facilitates the transition from digital forestry to smart forestry. While near-infrared spectroscopy applied to wood identification is well documented, the detailed mechanisms for chemometrics remain unclear. In this study, twelve wood species were identified by using near-infrared spectroscopy combined with six machine learning algorithms (support vector machine, logistic regression, naïve Bayes, k-nearest neighbors, random forest, and artificial neural network). Above all, isolated forest and local outlier factor were used to detect and exclude outliers. Then feature engineering strategies were developed from three perspectives to process feature matrices: feature selection, feature extraction, and feature selection combined with feature extraction. Next, the learning curve, grid search method, and K-fold cross-validation were used to optimize the model parameters. Finally, the accuracy, operation time, and confusion matrix were used to evaluate the model performance. When the local outlier factor was used to remove outliers and principal component analysis was used to extract features, the support-vector-machine-based wood-species identification model produced the most accurate results, with 98.24% accuracy. These results offer new avenues for constructing automatic wood-identification systems.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"77 1","pages":"326 - 337"},"PeriodicalIF":2.4,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46389528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Although highly desirable, the nature of wood-cellulose in its native state has remained difficult to comprehend. Contrary to the traditional acceptance of wood-cellulose being crystalline, in 2016, the authors’ research found that the cellulose was not crystalline. Here, additional evidence is presented that further supports the non-crystalline model. One of the key pieces of evidence was obtained by 64% H2SO4 hydrolysis of tension- and opposite-aspen woods (TW and OW, respectively). The TW (G-layer rich) yielded significant amount of CNCs (TW-CNCs, 20.7%), the OW yielded a much lower amount (OW-CNCs, 5.4%). Although a higher yield of TW-CNCs was expected due to the presence crystalline cellulose in the G-layer, the lower yield of the OW-CNCs was a surprise because, assuming absence of G-layer, based on the authors’ earlier findings no CNCs were expected to be generated. To explain this anomaly, anatomical examination of the woods using stains was carried out which showed that some OW fibers also contained the crystalline G-layer and therefore, provided an explanation as to why the OW-CNCs were produced. The results clearly showed that the acid hydrolysis did not destroy the crystalline cellulose and therefore, in the case of a normal (G-layer free) wood which, as previously reported had not generated CNCs, the cellulose must have been non-crystalline. An additional indication of the wood’s S2 cellulose being not crystalline was the absence of the 93 cm−1 Raman band in the low frequency spectrum of the TW S2 layer. Further evidence was obtained by comparing low frequency Raman spectra of TW-CNCs, TW-holopulp, and aspen-holopulp as well as the mixture-samples of crystalline cellulose and xylan at the concentration levels of their occurrence in these holopulps. Overall, these findings provided further support to the contention that the native wood-cellulose is non-crystalline.
{"title":"Native state of wood cellulose: evidence that further supports its non-crystalline nature","authors":"U. Agarwal, R. Reiner, C. Báez, S. Ralph","doi":"10.1515/hf-2022-0176","DOIUrl":"https://doi.org/10.1515/hf-2022-0176","url":null,"abstract":"Abstract Although highly desirable, the nature of wood-cellulose in its native state has remained difficult to comprehend. Contrary to the traditional acceptance of wood-cellulose being crystalline, in 2016, the authors’ research found that the cellulose was not crystalline. Here, additional evidence is presented that further supports the non-crystalline model. One of the key pieces of evidence was obtained by 64% H2SO4 hydrolysis of tension- and opposite-aspen woods (TW and OW, respectively). The TW (G-layer rich) yielded significant amount of CNCs (TW-CNCs, 20.7%), the OW yielded a much lower amount (OW-CNCs, 5.4%). Although a higher yield of TW-CNCs was expected due to the presence crystalline cellulose in the G-layer, the lower yield of the OW-CNCs was a surprise because, assuming absence of G-layer, based on the authors’ earlier findings no CNCs were expected to be generated. To explain this anomaly, anatomical examination of the woods using stains was carried out which showed that some OW fibers also contained the crystalline G-layer and therefore, provided an explanation as to why the OW-CNCs were produced. The results clearly showed that the acid hydrolysis did not destroy the crystalline cellulose and therefore, in the case of a normal (G-layer free) wood which, as previously reported had not generated CNCs, the cellulose must have been non-crystalline. An additional indication of the wood’s S2 cellulose being not crystalline was the absence of the 93 cm−1 Raman band in the low frequency spectrum of the TW S2 layer. Further evidence was obtained by comparing low frequency Raman spectra of TW-CNCs, TW-holopulp, and aspen-holopulp as well as the mixture-samples of crystalline cellulose and xylan at the concentration levels of their occurrence in these holopulps. Overall, these findings provided further support to the contention that the native wood-cellulose is non-crystalline.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"77 1","pages":"305 - 317"},"PeriodicalIF":2.4,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49304223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Morikawa, Nobuhiro Yamasuso, T. Ashitani, Koetsu Takahashi
Abstract The Japanese longhorn beetle, Anaglyptus subfasciatus, infests coniferous trees resulting in stained wood and low-value discolored lumber. In this study, the discolored Hinoki (Chamaecyparis obtusa) wood was analysed by GC-MS for n-hexane extract, and laboratory wood block tests against termite was carried out. Stained wood had anti-termitic resistance similar to normal heartwood, and it had about twice the n-hexane extract by weight than obtained from heartwood. One compound, nerolidol, was characteristically found in the stained wood. The results suggest that the stained wood may have produced some bioactive components due to damage by wood decay organisms.
{"title":"Durability of Hinoki (Chamaecyparis obtusa) stained wood following Anaglyptus subfasciatus infestation","authors":"T. Morikawa, Nobuhiro Yamasuso, T. Ashitani, Koetsu Takahashi","doi":"10.1515/hf-2022-0183","DOIUrl":"https://doi.org/10.1515/hf-2022-0183","url":null,"abstract":"Abstract The Japanese longhorn beetle, Anaglyptus subfasciatus, infests coniferous trees resulting in stained wood and low-value discolored lumber. In this study, the discolored Hinoki (Chamaecyparis obtusa) wood was analysed by GC-MS for n-hexane extract, and laboratory wood block tests against termite was carried out. Stained wood had anti-termitic resistance similar to normal heartwood, and it had about twice the n-hexane extract by weight than obtained from heartwood. One compound, nerolidol, was characteristically found in the stained wood. The results suggest that the stained wood may have produced some bioactive components due to damage by wood decay organisms.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"77 1","pages":"378 - 382"},"PeriodicalIF":2.4,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41601996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Suvi Kyyrö, M. Altgen, T. Belt, Hanna Seppäläinen, C. Brischke, P. Heinze, H. Militz, L. Rautkari
Abstract The effects of pressurized hot water extraction (HWE) treatment on the mould resistance of wood have not been extensively investigated yet. The activity of the mould fungi is dependent on the availability of nutrients. Therefore, the soluble degradation products produced during HWE treatment could affect the wood’s susceptibility to mould growth. Scots pine (Pinus sylvestris L.) sapwood specimens were treated with HWE at 140 °C for 1–5 h. Afterwards, the degradation products were either removed via leaching or the wood was dried without applying the leaching procedure. The surface layer (1.5 mm) was removed from half of the leached and non-leached specimens. The resistance of the specimens against mould growth was tested in an incubation chamber. HWE treated wood showed a higher susceptibility to mould growth when it was neither leached nor subjected to surface removal. The susceptibility of wood to mould fungi depended on the availability of hemicellulose-based degradation products produced during HWE treatment. These degradation products were removable via a leaching procedure, but also by removing the outermost layer of the wood. The results show the relevance of removing HWE degradation products located on the wood surface in improving resistance against mould growth.
{"title":"Effect of pressurized hot water extraction on the resistance of Scots pine sapwood against mould fungi","authors":"Suvi Kyyrö, M. Altgen, T. Belt, Hanna Seppäläinen, C. Brischke, P. Heinze, H. Militz, L. Rautkari","doi":"10.1515/hf-2022-0190","DOIUrl":"https://doi.org/10.1515/hf-2022-0190","url":null,"abstract":"Abstract The effects of pressurized hot water extraction (HWE) treatment on the mould resistance of wood have not been extensively investigated yet. The activity of the mould fungi is dependent on the availability of nutrients. Therefore, the soluble degradation products produced during HWE treatment could affect the wood’s susceptibility to mould growth. Scots pine (Pinus sylvestris L.) sapwood specimens were treated with HWE at 140 °C for 1–5 h. Afterwards, the degradation products were either removed via leaching or the wood was dried without applying the leaching procedure. The surface layer (1.5 mm) was removed from half of the leached and non-leached specimens. The resistance of the specimens against mould growth was tested in an incubation chamber. HWE treated wood showed a higher susceptibility to mould growth when it was neither leached nor subjected to surface removal. The susceptibility of wood to mould fungi depended on the availability of hemicellulose-based degradation products produced during HWE treatment. These degradation products were removable via a leaching procedure, but also by removing the outermost layer of the wood. The results show the relevance of removing HWE degradation products located on the wood surface in improving resistance against mould growth.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"77 1","pages":"348 - 355"},"PeriodicalIF":2.4,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46621517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}