Journal of Wood Science最新文献_第10页

Synthesis of highly deuterated coniferyl alcohol for silencing of NMR signals in the resulting dehydrogenative polymer 高氘化松柏醇的合成，用于在脱氢聚合物中沉默核磁共振信号

IF 2.9 3区农林科学

Journal of Wood Science Pub Date : 2022-08-12 DOI: 10.1186/s10086-022-02048-z

Shigetomi, Kengo, Tokizawa, Mana, Uraki, Yasumitsu

{"title":"Synthesis of highly deuterated coniferyl alcohol for silencing of NMR signals in the resulting dehydrogenative polymer","authors":"Shigetomi, Kengo, Tokizawa, Mana, Uraki, Yasumitsu","doi":"10.1186/s10086-022-02048-z","DOIUrl":"https://doi.org/10.1186/s10086-022-02048-z","url":null,"abstract":"To establish a facile methodology for the elucidation of the lignin chain-growth mechanism, the preparation of monolignol that does not show NMR signals in the dehydrogenative polymer (DHP) was attempted. As a monolignol of which aliphatic moieties were deuterated, coniferyl alcohol-d7 was successfully synthesized from protocatechualdehyde and malonic acid via the modified Knoevenagel–Doebner reaction and the Luche reduction. The process achieved high to excellent deuteration efficiencies at the aimed positions (i.e., methoxy: > 99%D, α: > 99%D, β: 92%D, and γ: 98%D). DHP was prepared solely from coniferyl alcohol-d7, and its NMR spectra were compared with those from coniferyl alcohol. The results indicated that: (1) the deuterium atoms at methoxy group, α- and β-positions were highly retained even in the DHP, and their signals were effectively suppressed; (2) a part of the deuterium at γ-position was replaced with H through the reaction; (3) meanwhile, the formation of γ-CH2 was negligible. This study demonstrated that coniferyl alcohol-d7 could “silence” the majority of the signals even when converted to DHP. Highly deuterated monolignols can be a unique molecular tool that can differentiate the signals of interest from those derived from monolignols.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"21 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138528641","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}

引用次数: 0

Experimental study on the embedment strength of smooth dowels inserted in cross-laminated timber narrow side 交叉层合材窄边光滑销钉嵌入强度试验研究

IF 2.9 3区农林科学

Journal of Wood Science Pub Date : 2022-08-05 DOI: 10.1186/s10086-022-02055-0

Long, Weiguo, Ou, Jiajia, Sun, Xiaofeng, Huang, Xinyue, He, Minjuan, Li, Zheng

{"title":"Experimental study on the embedment strength of smooth dowels inserted in cross-laminated timber narrow side","authors":"Long, Weiguo, Ou, Jiajia, Sun, Xiaofeng, Huang, Xinyue, He, Minjuan, Li, Zheng","doi":"10.1186/s10086-022-02055-0","DOIUrl":"https://doi.org/10.1186/s10086-022-02055-0","url":null,"abstract":"The embedment properties of the dowel-type fasteners is a fundamental parameter that can determine the shear resisting performance of the connections utilized in cross-laminated timber (CLT) structures. To investigate the embedment strength of the smooth dowels inserted in CLT narrow side, totally 504 CLT embedment specimens were tested to evaluate the effects of the influencing factors on the embedment strength, which included the loading angle, the embedment angle, the embedment position, the diameter of the dowels, and the gaps between the lumbers. The existing predictive equations of the embedment strength were validated based on the experimental results, and modified empirical equations were proposed for a more accurate prediction on the average embedment strength. It is found that when the loading direction with a loading angle of 90 degree is parallel to the adhesive layer, for the dowels embedded in the core layer and for those embedded between layers, the average embedment strength decreases by 27.89% and by 33.61% with an increase of the diameter from 8 to 24 mm, respectively. When the loading direction is perpendicular to the adhesive layer, the average embedment strength of the smooth dowels with an embedment angle of 90 degree is 85.25–218.96% higher than that of the dowels with an embedment angle of 0 degree. Furthermore, almost no drop can be identified for the embedment strength of the dowels with an embedment angle of 0 degree when the gap exists in their embedment position. A more accurate prediction on the average embedment strength can be achieved based on the modified empirical equations.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"67 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2022-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138528647","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}

引用次数: 7

Interaction between particle size and mixing ratio on porosity and properties of tea oil camellia (Camellia oleifera Abel.) shells-based particleboard 粒径和混合比对茶油-油茶壳刨花板孔隙率和性能的影响

IF 2.9 3区农林科学

Journal of Wood Science Pub Date : 2022-07-23 DOI: 10.1186/s10086-022-02052-3

Choupani Chaydarreh, Kamran, Lin, Xiuyi, Guan, Litao, Hu, Chuanshuang

{"title":"Interaction between particle size and mixing ratio on porosity and properties of tea oil camellia (Camellia oleifera Abel.) shells-based particleboard","authors":"Choupani Chaydarreh, Kamran, Lin, Xiuyi, Guan, Litao, Hu, Chuanshuang","doi":"10.1186/s10086-022-02052-3","DOIUrl":"https://doi.org/10.1186/s10086-022-02052-3","url":null,"abstract":"This study investigated the interaction between particle size and mixing ratio on the porosity of particleboard and in consequence its effect on the physical and mechanical properties of panels. Tea Oil Camellia Shell (TOCS), which could provide 1.8 million tons of lignocellulose raw material annually, can be a useful resource for particleboard production. In that regard, particleboards with different particle sizes (coarse and fine) and mixing ratios (wood and TOCS) bonded with Polymethylene polyphenyl polyisocyanate (pMDI) were investigated. The results showed that particleboard made with TOCS particles had higher densities than those of commercial wood particles. Furthermore, particleboards made with fine particles had lower porosity. The average values for physical and mechanical properties have shown that except for thickness swelling (TS), most properties were better with coarse particles. In terms of all properties, results showed that adding 50% of commercial wood in conjunction with TOCS particles regardless of particle size can offer acceptable results, which qualified all requirements of EN 312:2010 standard for P2-type particleboard (boards for interior fitments (including furniture) for use in dry conditions). In addition, due to the porous structure of the shells, TOCS-based particleboards have better thermal conductivity compared to wood-based particleboards.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"5 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2022-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138528639","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}

引用次数: 5

Experimental and nonlinear finite-element analysis study on lateral push resistance of San-dou components perpendicular and parallel to grain in traditional timber buildings 传统木结构建筑中垂直与平行于木纹的三斗构件侧推阻力试验与非线性有限元分析研究

IF 2.9 3区农林科学

Journal of Wood Science Pub Date : 2022-07-11 DOI: 10.1186/s10086-022-02049-y

Chengwen Zhang, Qing Chun, Yijie Lin, Hao Wang, Pan Li

引用次数: 1

Application of a bending vibration method without weighing specimens to the practical wooden members conditions 不称重的弯曲振动法在实际木结构条件下的应用

IF 2.9 3区农林科学

Journal of Wood Science Pub Date : 2022-06-28 DOI: 10.1186/s10086-022-02046-1

Y. Kubojima, Satomi Sonoda, Hideo Kato

引用次数: 0

IF 2.9 3区农林科学