Both of straight and inclining poplar clone 107 tree were selected for studying materials in this paper.The optimal pulping conditions was established by orthogonal experimental design both for normal wood and tension...Both of straight and inclining poplar clone 107 tree were selected for studying materials in this paper.The optimal pulping conditions was established by orthogonal experimental design both for normal wood and tension wood,and the quality of pulping and paper-making between normal wood and tension wood was compared with each other. Finally,potential application for improving paper quality of tension wood through increasing beating revolutions was discussed.The result showed that the optimal cooking condition for normal wood was alkali concentration 15%,the highest temperature 164℃,time at highest temperature 75 min,and for tension wood it was alkali concentration 13%,the highest temperature 160℃,time at highest temperature 40 min.Path coefficient of effect of alkali concentration both on pulp yield and kappa value was significant at different levels.By comparison between average result of normal wood and tension wood in quality of pulping and paper-making,it was found that tension wood had higher pulping yield and lower kappa value than normal wood. Furthermore,for all mechanical properties of paper, normal wood hold higher value than tension wood, and even near two times than tension wood,such as burst index and tensile index.However,difference of tear index was quite narrow.Result of one way ANOVA showed that difference of burst index and tear index between normal wood and tension wood was significant at the 0.001 level,of tear index was significant at the 0.05 level.Based on observation of cross surface of paper,it was assumed that contribution of gelatinous layer to rigidity of single fiber had hampered collapse and compression of fiber during paper formation,which is essential for exerting combination between fibers in paper.So, mechanical properties of tension wood paper were decreased accordingly.However,owing to high cellulose content of gelatinous layer,tension wood was easier to pulping than normal wood.Mechanical properties of tension wood paper could be improved by increasing beating revolutions,the final value even close to normal wood paper.But,the increasing effect had a limit.展开更多
以10种木材纹理样本为对象,研究了木材纹理参数体系的建立方法,并进行了分类识别的仿真实验。首先,针对木材纹理特点并结合类别可分性判据,构造了适于描述木材的空间灰度共生矩阵,并在此基础上提取了木材的11个纹理特征参数。其次,借助...以10种木材纹理样本为对象,研究了木材纹理参数体系的建立方法,并进行了分类识别的仿真实验。首先,针对木材纹理特点并结合类别可分性判据,构造了适于描述木材的空间灰度共生矩阵,并在此基础上提取了木材的11个纹理特征参数。其次,借助相关性分析对参数进行了特征选择,进而建立了能直接与人的感官对应的木材纹理参数体系。最后,利用 BP 神经网络分类器对木材样本进行了分类识别研究,识别率为87.50%,验证了参数体系的有效性,表明用本文提出的纹理参数体系对木材进行分类识别是可行的。展开更多
文摘Both of straight and inclining poplar clone 107 tree were selected for studying materials in this paper.The optimal pulping conditions was established by orthogonal experimental design both for normal wood and tension wood,and the quality of pulping and paper-making between normal wood and tension wood was compared with each other. Finally,potential application for improving paper quality of tension wood through increasing beating revolutions was discussed.The result showed that the optimal cooking condition for normal wood was alkali concentration 15%,the highest temperature 164℃,time at highest temperature 75 min,and for tension wood it was alkali concentration 13%,the highest temperature 160℃,time at highest temperature 40 min.Path coefficient of effect of alkali concentration both on pulp yield and kappa value was significant at different levels.By comparison between average result of normal wood and tension wood in quality of pulping and paper-making,it was found that tension wood had higher pulping yield and lower kappa value than normal wood. Furthermore,for all mechanical properties of paper, normal wood hold higher value than tension wood, and even near two times than tension wood,such as burst index and tensile index.However,difference of tear index was quite narrow.Result of one way ANOVA showed that difference of burst index and tear index between normal wood and tension wood was significant at the 0.001 level,of tear index was significant at the 0.05 level.Based on observation of cross surface of paper,it was assumed that contribution of gelatinous layer to rigidity of single fiber had hampered collapse and compression of fiber during paper formation,which is essential for exerting combination between fibers in paper.So, mechanical properties of tension wood paper were decreased accordingly.However,owing to high cellulose content of gelatinous layer,tension wood was easier to pulping than normal wood.Mechanical properties of tension wood paper could be improved by increasing beating revolutions,the final value even close to normal wood paper.But,the increasing effect had a limit.
基金黑龙江省自然科学基金项目((C2004-03C0308)哈尔滨市自然科学基金项日(2004AFX X J 0 20)
文摘以10种木材纹理样本为对象,研究了木材纹理参数体系的建立方法,并进行了分类识别的仿真实验。首先,针对木材纹理特点并结合类别可分性判据,构造了适于描述木材的空间灰度共生矩阵,并在此基础上提取了木材的11个纹理特征参数。其次,借助相关性分析对参数进行了特征选择,进而建立了能直接与人的感官对应的木材纹理参数体系。最后,利用 BP 神经网络分类器对木材样本进行了分类识别研究,识别率为87.50%,验证了参数体系的有效性,表明用本文提出的纹理参数体系对木材进行分类识别是可行的。