Wood is a heterogeneous material with significant variation among species. This inherent complexity poses a challenge to the continuous expansion of our understanding of the kraft process; yet previous pulping research has mainly been limited to a few species. This study investigates variations among some less studied species and their cell wall level delignification behaviour during kraft pulping. Ground wood of birch, beech, aspen, and alder were pulped at near-constant composition and temperature conditions. Minor, yet significant, differences in the rates of their delignification were observed: aspen had a pronounced fast rate during the initial stage, whereas alder delignified more slowly relative to its high initial lignin content. The dissolution of xylan was substantially faster for birch. In contrast, no substantial differences were detected between the species in the molecular weight and structure of the dissolved wood components, suggesting that the different delignification behaviours stem from variations in the residual phase. The molecular weight distribution of dissolved lignin was uniform during the initial stage of pulping, which is indicative of rapid and extensive fragmentation. Subsequently, the weight increased continuously for the remainder of the process, suggesting that the mass transfer within the cell wall influenced the overall delignification kinetics.
{"title":"A comparative study of the cell wall level delignification behaviour of four Nordic hardwoods during kraft pulping","authors":"Linus Kron, Merima Hasani, Hans Theliander","doi":"10.1515/hf-2024-0011","DOIUrl":"https://doi.org/10.1515/hf-2024-0011","url":null,"abstract":"Wood is a heterogeneous material with significant variation among species. This inherent complexity poses a challenge to the continuous expansion of our understanding of the kraft process; yet previous pulping research has mainly been limited to a few species. This study investigates variations among some less studied species and their cell wall level delignification behaviour during kraft pulping. Ground wood of birch, beech, aspen, and alder were pulped at near-constant composition and temperature conditions. Minor, yet significant, differences in the rates of their delignification were observed: aspen had a pronounced fast rate during the initial stage, whereas alder delignified more slowly relative to its high initial lignin content. The dissolution of xylan was substantially faster for birch. In contrast, no substantial differences were detected between the species in the molecular weight and structure of the dissolved wood components, suggesting that the different delignification behaviours stem from variations in the residual phase. The molecular weight distribution of dissolved lignin was uniform during the initial stage of pulping, which is indicative of rapid and extensive fragmentation. Subsequently, the weight increased continuously for the remainder of the process, suggesting that the mass transfer within the cell wall influenced the overall delignification kinetics.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"7 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529512","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}
Using pyrolysis–gas chromatography–mass spectrometry, the lignin composition was analysed in normal and reaction wood samples grown at three stem inclination angles in Gardenia jasminoides, which forms compression wood-like reaction wood. Lignin content among the samples was not significantly different. However, the reaction wood samples with larger stem inclination angles showed a lower syringyl/guaiacyl ratio. In conclusion, the degree of inclination affected the lignin composition in G. jasminoides reaction wood, and qualitative changes in lignin might be necessary to mechanically support the stems in this species.
{"title":"Determination of lignin composition in compression wood-like reaction wood of angiosperm Gardenia jasminoides by pyrolysis–gas chromatography–mass spectrometry","authors":"Haruna Aiso, Tatsuya Ashitani, Futoshi Ishiguri","doi":"10.1515/hf-2023-0123","DOIUrl":"https://doi.org/10.1515/hf-2023-0123","url":null,"abstract":"Using pyrolysis–gas chromatography–mass spectrometry, the lignin composition was analysed in normal and reaction wood samples grown at three stem inclination angles in <jats:italic>Gardenia jasminoides</jats:italic>, which forms compression wood-like reaction wood. Lignin content among the samples was not significantly different. However, the reaction wood samples with larger stem inclination angles showed a lower syringyl/guaiacyl ratio. In conclusion, the degree of inclination affected the lignin composition in <jats:italic>G. jasminoides</jats:italic> reaction wood, and qualitative changes in lignin might be necessary to mechanically support the stems in this species.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"65 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140936368","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}
Jieying Yuan, Yibo Li, Shulei Li, Zheyun Liu, Yunjing Lu, Shuoyu Dang, Fan Ding, Ruijin Yu, Jie Chu
Pretreatment serves as an important step in maximizing the efficient utilization of woody biomass feedstock. This study focused on enhancing the component and structural properties of apple wood to optimize the utilization of apple wood resources effectively. This study presents the optimization of, the apple wood pretreatment system, combining bioenzyme and hydrothermal treatments. This study aimed to investigate the effect of different bioenzyme pretreatment conditions on the components and structural properties of apple wood extract and to analyze the feasibility of enzyme solution reuse. Fourier transform infrared spectroscopy analysis revealed an increase in cellulose content in the wood flour following enzyme treatment. Concurrently, changes in characteristic peaks indicated an increased hemicellulose content and a reduction in lignin content after the pretreatment, correlating with fraction analysis results. Scanning electron microscopy illustrated that the dense structure of the fiber surface was disrupted after treatment. Notably, the results indicated that the recovered biocomposite enzymes exhibited excellent activity, suggesting their potential for reuse.
{"title":"Hydrothermal enzyme pretreatment on structure and properties of apple branches","authors":"Jieying Yuan, Yibo Li, Shulei Li, Zheyun Liu, Yunjing Lu, Shuoyu Dang, Fan Ding, Ruijin Yu, Jie Chu","doi":"10.1515/hf-2023-0103","DOIUrl":"https://doi.org/10.1515/hf-2023-0103","url":null,"abstract":"Pretreatment serves as an important step in maximizing the efficient utilization of woody biomass feedstock. This study focused on enhancing the component and structural properties of apple wood to optimize the utilization of apple wood resources effectively. This study presents the optimization of, the apple wood pretreatment system, combining bioenzyme and hydrothermal treatments. This study aimed to investigate the effect of different bioenzyme pretreatment conditions on the components and structural properties of apple wood extract and to analyze the feasibility of enzyme solution reuse. Fourier transform infrared spectroscopy analysis revealed an increase in cellulose content in the wood flour following enzyme treatment. Concurrently, changes in characteristic peaks indicated an increased hemicellulose content and a reduction in lignin content after the pretreatment, correlating with fraction analysis results. Scanning electron microscopy illustrated that the dense structure of the fiber surface was disrupted after treatment. Notably, the results indicated that the recovered biocomposite enzymes exhibited excellent activity, suggesting their potential for reuse.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"41 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140887845","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}
Jiawei Huang, Xiuyi Lin, Weiwei Zhang, Litao Guan, Jiangtao Xu, Jin Gu, Yonghui Zhou, Chuanshuang Hu
Camellia oleifera Abel. shell (COS) is an agricultural waste in quantities exceeding a million tons annually. The ultrastructure of the COS cell wall and the distribution of lignocellulose components were investigated. The microscopic results showed that COS contains two types of cells, sclerenchyma cells (SC) and parenchyma cells (PC). SC contained 50.4 % hemicellulose, 17.6 % cellulose and 30.9 % lignin while PC contained 35.2 % hemicellulose, 23.7 % cellulose and 35.0 % lignin. The distribution of lignocellulose components in COS is non-homogeneous. Lignin is alternately distributed with polysaccharides in the PC wall. In SC, hemicellulose is mainly present in the secondary wall S2, while lignin was mainly found in the compound middle lamella, and cellulose mainly exists in the secondary wall, S3. A comprehensive model of the cell wall ultrastructure and lignocellulose distribution of COS was given. This study provides a fundamental understanding of COS cell walls and can aid in the future graded utilization of COS.
油茶果壳（COS）是一种农业废弃物，每年的产量超过一百万吨。研究人员对 COS 细胞壁的超微结构和木质纤维素成分的分布进行了调查。显微镜结果显示，COS 包含两种类型的细胞，即小叶细胞（SC）和实质细胞（PC）。SC含有50.4%的半纤维素、17.6%的纤维素和30.9%的木质素，而PC含有35.2%的半纤维素、23.7%的纤维素和35.0%的木质素。木质纤维素成分在 COS 中的分布并不均匀。木质素与多糖交替分布在 PC 壁中。在 SC 中，半纤维素主要存在于次生壁 S2 中，而木质素主要存在于复合中层中，纤维素主要存在于次生壁 S3 中。该研究给出了 COS 细胞壁超微结构和木质纤维素分布的综合模型。这项研究提供了对 COS 细胞壁的基本认识，有助于今后对 COS 的分级利用。
{"title":"Cell wall composition of Camellia oleifera Abel. shell: new insights into its composition distribution and ultrastructure","authors":"Jiawei Huang, Xiuyi Lin, Weiwei Zhang, Litao Guan, Jiangtao Xu, Jin Gu, Yonghui Zhou, Chuanshuang Hu","doi":"10.1515/hf-2023-0120","DOIUrl":"https://doi.org/10.1515/hf-2023-0120","url":null,"abstract":"<jats:italic>Camellia oleifera</jats:italic> Abel. shell (COS) is an agricultural waste in quantities exceeding a million tons annually. The ultrastructure of the COS cell wall and the distribution of lignocellulose components were investigated. The microscopic results showed that COS contains two types of cells, sclerenchyma cells (SC) and parenchyma cells (PC). SC contained 50.4 % hemicellulose, 17.6 % cellulose and 30.9 % lignin while PC contained 35.2 % hemicellulose, 23.7 % cellulose and 35.0 % lignin. The distribution of lignocellulose components in COS is non-homogeneous. Lignin is alternately distributed with polysaccharides in the PC wall. In SC, hemicellulose is mainly present in the secondary wall S<jats:sub>2</jats:sub>, while lignin was mainly found in the compound middle lamella, and cellulose mainly exists in the secondary wall, S<jats:sub>3</jats:sub>. A comprehensive model of the cell wall ultrastructure and lignocellulose distribution of COS was given. This study provides a fundamental understanding of COS cell walls and can aid in the future graded utilization of COS.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"2013 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140887778","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}
The porosity of cell walls, as indicated by diffusion of rhodamine B dye, in the wood of Douglas fir, radiata pine, New Zealand red beech and Shining gum was compared under dynamic conditions using fluorescence recovery after photobleaching. The comparative diffusion rate was estimated using the half-life of fluorescence recovery under water-saturated conditions performed on transverse sections. All four wood species showed similar diffusion behaviour in tracheid or fibre cell walls with slower diffusion in the middle lamella layer compared to the secondary cell wall. Within the S2 layer of the secondary wall two regions were observed, an outer region with a slow diffusion rate and an inner region with a higher diffusion rate. Vessel cell walls showed slightly slower diffusion rates. Diffusion of rhodamine B dye appears to occur primarily along the fibre axis and is probably somewhat different to water in its behaviour. This suggests that pores are aligned with cellulose microfibrils. The dye diffusion rate was estimated to be in the range of 50–100 nm2 s−1. This has implications for understanding wood drying behaviour and chemical modification of wood by infiltration with small molecules as well as water storage in living trees.
在动态条件下，使用光漂白后荧光恢复法比较了花旗松、辐射松、新西兰红山毛榉和新宁胶木材中通过罗丹明 B 染料扩散显示的细胞壁孔隙率。在横切面上进行的水饱和条件下，利用荧光恢复的半衰期估算比较扩散速率。所有四种木材在气管或纤维细胞壁中都表现出类似的扩散行为，与次生细胞壁相比，中间薄片层的扩散速度较慢。在次生细胞壁的 S2 层中观察到两个区域，一个是扩散速度较慢的外层区域，另一个是扩散速度较高的内层区域。血管细胞壁的扩散速度稍慢。罗丹明 B 染料的扩散似乎主要沿纤维轴线进行，其行为可能与水有些不同。这表明孔隙是与纤维素微纤维对齐的。染料扩散速率估计在 50-100 nm2 s-1 之间。这对理解木材干燥行为、小分子渗透对木材的化学修饰以及活树中的储水都有影响。
{"title":"Dynamic diffusion in softwood and hardwood cell walls using fluorescence recovery after photobleaching","authors":"Lloyd Donaldson, Hamish Pearson","doi":"10.1515/hf-2024-0007","DOIUrl":"https://doi.org/10.1515/hf-2024-0007","url":null,"abstract":"The porosity of cell walls, as indicated by diffusion of rhodamine B dye, in the wood of Douglas fir, radiata pine, New Zealand red beech and Shining gum was compared under dynamic conditions using fluorescence recovery after photobleaching. The comparative diffusion rate was estimated using the half-life of fluorescence recovery under water-saturated conditions performed on transverse sections. All four wood species showed similar diffusion behaviour in tracheid or fibre cell walls with slower diffusion in the middle lamella layer compared to the secondary cell wall. Within the S<jats:sub>2</jats:sub> layer of the secondary wall two regions were observed, an outer region with a slow diffusion rate and an inner region with a higher diffusion rate. Vessel cell walls showed slightly slower diffusion rates. Diffusion of rhodamine B dye appears to occur primarily along the fibre axis and is probably somewhat different to water in its behaviour. This suggests that pores are aligned with cellulose microfibrils. The dye diffusion rate was estimated to be in the range of 50–100 nm<jats:sup>2</jats:sup> s<jats:sup>−1</jats:sup>. This has implications for understanding wood drying behaviour and chemical modification of wood by infiltration with small molecules as well as water storage in living trees.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"100 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140630180","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}
Marie Soula, Fabienne Samyn, Sophie Duquesne, Véronic Landry
Wood is a natural composite widely employed as a residential building interior finishing. Although wood is readily available and offers benefits to the occupants, such as enhanced well-being, it is rarely employed in commercial construction due, amongst others, to the potential hazard of fire propagation. The application of flame retardant (FR) treatments leads to a reduction of wood flammability and supports wood as interior finishing. Polyelectrolyte complexes (PECs) deposition is an innovative surface treatment that has already proven its efficiency for fabrics. For wood, recent studies have highlighted that the weight gain impacted the fire-retardancy, and a minimum of 2 wt.-% was set to obtain fire protection. This study explored the potential of surface delignification to activate the wood surface and facilitate the PEC impregnation. Yellow birch (Betula alleghaniensis, Britt.) was surface delignified (0.3 mm) using sodium chlorite. The treatment impact on wood was evaluated by spectroscopy analysis (FTIR, Raman), and the increase in wood wettability was demonstrated (contact angle decreases from 50° to 35° after the surface delignification). Then, PECs consisting of polyethyleneimine and sodium phytate were surface impregnated in wood and delignified wood. The flame retardancy was evaluated using a cone calorimeter. Despite the increase in weight gain (1.5 wt.-% ± 0.3 wt.-% to 4.3 wt.-% ± 2.5 wt.-%), fire performance was not improved. This study demonstrates that lignin strongly affects char formation, even in the presence of PECs.
{"title":"Impact of surface delignification on fire retardancy of wood treated with polyelectrolyte complexes","authors":"Marie Soula, Fabienne Samyn, Sophie Duquesne, Véronic Landry","doi":"10.1515/hf-2023-0059","DOIUrl":"https://doi.org/10.1515/hf-2023-0059","url":null,"abstract":"Wood is a natural composite widely employed as a residential building interior finishing. Although wood is readily available and offers benefits to the occupants, such as enhanced well-being, it is rarely employed in commercial construction due, amongst others, to the potential hazard of fire propagation. The application of flame retardant (FR) treatments leads to a reduction of wood flammability and supports wood as interior finishing. Polyelectrolyte complexes (PECs) deposition is an innovative surface treatment that has already proven its efficiency for fabrics. For wood, recent studies have highlighted that the weight gain impacted the fire-retardancy, and a minimum of 2 wt.-% was set to obtain fire protection. This study explored the potential of surface delignification to activate the wood surface and facilitate the PEC impregnation. Yellow birch (<jats:italic>Betula alleghaniensis</jats:italic>, Britt.) was surface delignified (0.3 mm) using sodium chlorite. The treatment impact on wood was evaluated by spectroscopy analysis (FTIR, Raman), and the increase in wood wettability was demonstrated (contact angle decreases from 50° to 35° after the surface delignification). Then, PECs consisting of polyethyleneimine and sodium phytate were surface impregnated in wood and delignified wood. The flame retardancy was evaluated using a cone calorimeter. Despite the increase in weight gain (1.5 wt.-% ± 0.3 wt.-% to 4.3 wt.-% ± 2.5 wt.-%), fire performance was not improved. This study demonstrates that lignin strongly affects char formation, even in the presence of PECs.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"30 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140315856","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}
The mechanical properties of wood are affected by member size and loading rate. Axial compression tests with different seismic strain rates and sizes of specimens were carried out to investigate the static and dynamic dimensional effects of Yunnan pine timber. And obtained load-displacement curves, compressive strength, modulus of elasticity, peak strain and Poisson’s ratio. Weibull’s weakest chain theory, Bazant’s law of dimensional effects and Carpinteri’s law of multiple fractal dimensional effects were used to analyze the dimensional effects on the compressive strength of wood, and to establish a wood strength model that takes strain rate effects and dimensional effects into account. The results showed that the compressive strength, elastic modulus, and Poisson’s ratio of Yunnan pine wood exhibit both size and strain rate effects. Under the coupling effect of strain rate effect and size effect, the size effect of Yunnan pine wood strength decreases with increasing strain rate, while the strain rate effect increases with increasing size. A size effect model for compressive strength of wood considering strain rate effect based on three theories and experimental data can well describe the dynamic size effect of Yunnan pine wood strength.
{"title":"A study of dimensional effects on the stress characteristics of Yunnan pine shafts considering seismic strain rates","authors":"Jianhui Liu, Guolin Xu, Yashuang Bai, Yujie Lin, Wenqing Geng","doi":"10.1515/hf-2023-0098","DOIUrl":"https://doi.org/10.1515/hf-2023-0098","url":null,"abstract":"The mechanical properties of wood are affected by member size and loading rate. Axial compression tests with different seismic strain rates and sizes of specimens were carried out to investigate the static and dynamic dimensional effects of Yunnan pine timber. And obtained load-displacement curves, compressive strength, modulus of elasticity, peak strain and Poisson’s ratio. Weibull’s weakest chain theory, Bazant’s law of dimensional effects and Carpinteri’s law of multiple fractal dimensional effects were used to analyze the dimensional effects on the compressive strength of wood, and to establish a wood strength model that takes strain rate effects and dimensional effects into account. The results showed that the compressive strength, elastic modulus, and Poisson’s ratio of Yunnan pine wood exhibit both size and strain rate effects. Under the coupling effect of strain rate effect and size effect, the size effect of Yunnan pine wood strength decreases with increasing strain rate, while the strain rate effect increases with increasing size. A size effect model for compressive strength of wood considering strain rate effect based on three theories and experimental data can well describe the dynamic size effect of Yunnan pine wood strength.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"13 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140303331","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}
This study investigated the inhibition effect of nanoscale silver–copper particle (20 nm) against Coriolus versicolor and Gloeophyllumtrabeum. Poplar wood samples (Populus L.) were vacuum-impregnated using aqueous nano-AgCu solutions at concentrations of 0.01 %, 0.02 %, 0.03 %, 0.05 %, 0.075 %, and 0.1 %. Alkaline copper quaternary (ACQ, 0.1 %), boric acid (0.2 %) and untreated control group (CK) were employed for comparisons. Decay resistance and leachability were studied. The anti-fungi effects were compared between nano-AgCu, nano-Ag, Ag+ (silver nitrate), Cu2+ (copper nitrate), and a composite of Ag+–Cu2+. Nano-AgCu particle exhibited effective resistance to fungi after 12 weeks of exposure. The threshold retention of the nano-AgCu against C. versicolor and G. trabeum on poplar wood was 0.19 kg m−3 and 0.62 kg m−3, respectively. The silver–copper nanoparticles demonstrated excellent leach resistance, and the inhibition effect was retained after leaching. The nano-AgCu particle provided better antifungal effects than single ions or metal nanoparticles. This study illustrates the potential of using nano-AgCu particle as an efficient wood preservative compared to commercial water-soluble preservatives.
本研究探讨了纳米银铜微粒（20 纳米）对 Coriolus versicolor 和 Gloeophyllum trabeum 的抑制作用。使用浓度为 0.01 %、0.02 %、0.03 %、0.05 %、0.075 % 和 0.1 % 的纳米银铜水溶液对杨木样本（杨树）进行真空浸渍。碱性季铵盐铜（ACQ，0.1 %）、硼酸（0.2 %）和未经处理的对照组（CK）被用来进行比较。研究了抗腐烂性和浸出性。比较了纳米银铜、纳米银、Ag+（硝酸银）、Cu2+（硝酸铜）和 Ag+-Cu2+ 复合材料的抗真菌效果。纳米 AgCu 粒子在暴露 12 周后表现出对真菌的有效抵抗力。纳米银铜在杨木上对 C. versicolor 和 G. trabeum 的阈值保留分别为 0.19 kg m-3 和 0.62 kg m-3。纳米银铜粒子表现出优异的耐浸出性，浸出后仍能保持抑制效果。与单一离子或金属纳米粒子相比，纳米银铜粒子具有更好的抗真菌效果。这项研究表明，与商用水溶性防腐剂相比，纳米银铜微粒具有作为高效木材防腐剂的潜力。
{"title":"Poplar wood treated with nano-silver–copper particles: fungal degradation and leaching analysis","authors":"Xiwei Wang, Tengfei Yi, Hongxue Luo, Yanran Qi, Fengbiao Yao, Yiliang Liu, Yongfeng Li","doi":"10.1515/hf-2023-0128","DOIUrl":"https://doi.org/10.1515/hf-2023-0128","url":null,"abstract":"This study investigated the inhibition effect of nanoscale silver–copper particle (20 nm) against <jats:italic>Coriolus versicolor</jats:italic> and <jats:italic>Gloeophyllum</jats:italic> <jats:italic>trabeum</jats:italic>. Poplar wood samples (<jats:italic>Populus</jats:italic> L.) were vacuum-impregnated using aqueous nano-AgCu solutions at concentrations of 0.01 %, 0.02 %, 0.03 %, 0.05 %, 0.075 %, and 0.1 %. Alkaline copper quaternary (ACQ, 0.1 %), boric acid (0.2 %) and untreated control group (CK) were employed for comparisons. Decay resistance and leachability were studied. The anti-fungi effects were compared between nano-AgCu, nano-Ag, Ag<jats:sup>+</jats:sup> (silver nitrate), Cu<jats:sup>2+</jats:sup> (copper nitrate), and a composite of Ag<jats:sup>+</jats:sup>–Cu<jats:sup>2+</jats:sup>. Nano-AgCu particle exhibited effective resistance to fungi after 12 weeks of exposure. The threshold retention of the nano-AgCu against <jats:italic>C. versicolor</jats:italic> and <jats:italic>G. trabeum</jats:italic> on poplar wood was 0.19 kg m<jats:sup>−3</jats:sup> and 0.62 kg m<jats:sup>−3</jats:sup>, respectively. The silver–copper nanoparticles demonstrated excellent leach resistance, and the inhibition effect was retained after leaching. The nano-AgCu particle provided better antifungal effects than single ions or metal nanoparticles. This study illustrates the potential of using nano-AgCu particle as an efficient wood preservative compared to commercial water-soluble preservatives.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"30 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140301534","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}
Humins are heterogeneous and polydisperse furanic macromolecules derived from sugar biorefinery. Improving wood properties by humination has become of interest recently. This study examined the photodegradation stability of European pine sapwood microveneers modified with humins at different concentrations of citric acid (CA) and succinic acid (SA) as reaction catalysts, e.g., 1.5 %, 3 %, and 4.5 % wt.%. The photostability of huminated wood was assessed after 48 h, 96 h, and 144 h of exposure to the accelerated weathering test by means of mass loss and finite-span tensile strength. The results were compared with unmodified and also unweathered samples. The FT-IR spectroscopy showed apparent changes in the chemical structure of wood by humination modifications. The weight percentage gains of the samples increased with increasing the concentration of the catalyst. While no differences were observed between the samples after two weeks of the water leaching. The strength losses of weathered microveneers were, however, mostly reduced by humin-based formulas containing catalysts, where the microveneers modified with 1.5 % and 3 % CA showed respectively 32 % and 41 % lower strength loss values than the unmodified samples after 144 h of weathering. Overall, the results showed a high potential for humins to protect wood against photodegradation.
{"title":"Photodegradation stability of huminated European pine (Pinus sylvestris L.) microveneers","authors":"Amir Ghavidel, Reza Hosseinpourpia","doi":"10.1515/hf-2024-0006","DOIUrl":"https://doi.org/10.1515/hf-2024-0006","url":null,"abstract":"Humins are heterogeneous and polydisperse furanic macromolecules derived from sugar biorefinery. Improving wood properties by humination has become of interest recently. This study examined the photodegradation stability of European pine sapwood microveneers modified with humins at different concentrations of citric acid (CA) and succinic acid (SA) as reaction catalysts, e.g., 1.5 %, 3 %, and 4.5 % wt.%. The photostability of huminated wood was assessed after 48 h, 96 h, and 144 h of exposure to the accelerated weathering test by means of mass loss and finite-span tensile strength. The results were compared with unmodified and also unweathered samples. The FT-IR spectroscopy showed apparent changes in the chemical structure of wood by humination modifications. The weight percentage gains of the samples increased with increasing the concentration of the catalyst. While no differences were observed between the samples after two weeks of the water leaching. The strength losses of weathered microveneers were, however, mostly reduced by humin-based formulas containing catalysts, where the microveneers modified with 1.5 % and 3 % CA showed respectively 32 % and 41 % lower strength loss values than the unmodified samples after 144 h of weathering. Overall, the results showed a high potential for humins to protect wood against photodegradation.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"36 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140171060","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}
Lukas Sommerauer, Matthew Konkler, Gerald Presley, Thomas Schnabel, Alexander Petutschnigg, Barbara Hinterstoisser
Bark residues from Douglas fir are an abundant resource that is currently used primarily in low-value energy recovery or is landfilled. Bark extractives are rich in diverse compounds like terpenes, fatty acids, phenols, and sugars with potential uses in a variety of high value applications. The study explores the potential of enzymatic hydrolysis to improve phenolic compounds from Douglas fir bark. It also assesses differences in chemical composition among rhytidome, phloem, and comingled bark fractions from an industrial waste pile. Phloem fractions exhibit higher yields of extractives, rhytidome fractions have elevated lignin levels, while the comingled fraction lies between the two except in ash content which was higher than in the separated fractions. Fungal decay tests with Gloeophyllum trabeum and Coniophora puteana on extract treated wood suggest potential for growth inhibition in extracts, about 58–31 % and 30–7% mass loss (in average) respectively, but due to high mass loss at low concentrations an enzymatic modification approach seems crucial for enhanced inhibition. Growth responses in whole-cell fermentation approach display variability depending on the participating microorganisms. Enzymatic hydrolysis with beta-glucosidase improved the antioxidant properties of bark extracts and holds promise for altering the chemical composition and enhancing bioactivity.
{"title":"Douglas fir bark: composition, extracts utilization and enzymatic treatment for enrichment of bioactive constituents","authors":"Lukas Sommerauer, Matthew Konkler, Gerald Presley, Thomas Schnabel, Alexander Petutschnigg, Barbara Hinterstoisser","doi":"10.1515/hf-2023-0130","DOIUrl":"https://doi.org/10.1515/hf-2023-0130","url":null,"abstract":"Bark residues from Douglas fir are an abundant resource that is currently used primarily in low-value energy recovery or is landfilled. Bark extractives are rich in diverse compounds like terpenes, fatty acids, phenols, and sugars with potential uses in a variety of high value applications. The study explores the potential of enzymatic hydrolysis to improve phenolic compounds from Douglas fir bark. It also assesses differences in chemical composition among rhytidome, phloem, and comingled bark fractions from an industrial waste pile. Phloem fractions exhibit higher yields of extractives, rhytidome fractions have elevated lignin levels, while the comingled fraction lies between the two except in ash content which was higher than in the separated fractions. Fungal decay tests with <jats:italic>Gloeophyllum trabeum</jats:italic> and <jats:italic>Coniophora puteana</jats:italic> on extract treated wood suggest potential for growth inhibition in extracts, about 58–31 % and 30–7% mass loss (in average) respectively, but due to high mass loss at low concentrations an enzymatic modification approach seems crucial for enhanced inhibition. Growth responses in whole-cell fermentation approach display variability depending on the participating microorganisms. Enzymatic hydrolysis with beta-glucosidase improved the antioxidant properties of bark extracts and holds promise for altering the chemical composition and enhancing bioactivity.","PeriodicalId":13083,"journal":{"name":"Holzforschung","volume":"17 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140108179","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}
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