金佛山方竹基础物性及其时空变化规律  

Basic properties of Chimonobambusa utilis and its spatiotemporal variations

作　　者：刘文娟 王滔 赵福泽 林剑 Liu Wenjuan;Wang Tao;Zhao Fuze;Lin Jian(School of Materials Science and Technology,Key Laboratory of Wooden Material Science and Application of Ministry of Education,Beijing Forestry University,Beijing 100083,China;Industrial Development Planning Institute,National Forestry and Grassland Administration,Beijing 100010,China;Forestry Bureau of Tongzi County,Zunyi City,Zunyi 563299,Guizhou,China)

机构地区：[1]北京林业大学材料科学与技术学院,木质材料科学与应用教育部重点实验室,北京100083 [2]国家林业和草原局产业发展规划院,北京100010 [3]贵州省遵义市桐梓县林业局,贵州遵义563299

出　　处：《北京林业大学学报》2023年第3期127-136,共10页Journal of Beijing Forestry University

基　　金：中央高校基本科研业务费专项(2021ZY23);国家自然科学基金项目(31700492)。

摘　　要：【目的】为掌握金佛山方竹基础物性,探究其化学组分与物理力学性质随竹龄与轴向部位的变化规律,进而促进其秆材资源的合理高值化利用。【方法】本研究以1~5年生天然金佛山方竹为研究对象,依据相应国家标准测定其化学组分含量(本文指的是质量分数)与密度、干缩率、顺纹抗压强度、抗弯强度、弹性模量和硬度等物理力学性质,通过X射线衍射仪测定样品衍射曲线,进而计算其相对结晶度与微纤丝角度。【结果】金佛山方竹各化学组分含量随竹龄与轴向部位小幅度波动变化,且变化规律不显著。结晶度随竹龄增加先增大后逐渐减小,2年生最大,为50.39%,并随轴向部位升高逐渐增大。微纤丝角度随竹龄增加与轴向部位升高均先减小后增大,2年生中部最小,为9.10°。基本密度为0.513~0.693 g/cm^(3),全干密度为0.535~0.725 g/cm^(3),气干密度为0.556~0.756 g/cm^(3);各密度随竹龄增加与轴向部位升高均呈上升趋势,1~2年间显著增大,随后平稳增加至趋于稳定。全干干缩率和气干干缩率随竹龄增加与轴向部位升高均呈下降趋势,1~2年间显著下降,随后平稳下降,后者波动性相对较大。顺纹抗压强度为50.73~64.58 MPa,抗弯强度为114.09~134.26 MPa,弹性模量为8.45~12.42 GPa,三者均随竹龄增加均呈上升-下降-上升趋势,随轴向部位升高均呈上升趋势;内外侧硬度平均值为60.00~72.70 HD,其随竹龄增加与轴向部位升高均呈上升趋势。金佛山方竹的干缩率、顺纹抗压强度、抗弯弹性模量和硬度均受解剖构造与主要化学组分显著影响。【结论】金佛山方竹竹龄与竹秆轴向部位均影响其基础物性,但竹龄的影响更加显著;2年以上金佛山方竹秆材质基本成熟,可作为金佛山方竹的较佳砍伐竹龄。此外,物理力学性质与解剖构造和主要化学组分间存在一定的显著相关性。[Objective] This paper aims to further improve the high value-added utilization of culm resources of Chimonobambusa utilis,the chemical components,physical and mechanical properties were investigated,and the variation regularity with age and axial part of bamboo culm were also revealed.[Method] In this study,the natural plants of Chimonobambusa utilis were used as raw materials to determine the chemical component(mass fraction in this article) content and physical and mechanical properties,such as density,dry shrinkage,compressive strength parallel to grain,modulus of rapture(MOR),modulus of elasticity(MOE) and hardness according to the national standards.The crystallinity of cellulose and microfibril angle was calculated from the results of X-ray diffraction.[Result] The content of each chemical component of Chimonobambusa utilis varied slightly with the age and axial part,and the variation pattern was not significant.The crystallinity increased with the age of bamboo and then decreased gradually,with a maximum of 50.39% at 2 years old,and increased gradually with the increase of axial part.The microfibril angle decreased and then increased with increasing age and axial part,and the smallest angle was9.10° in the middle of 2 years old.The basic density ranged from 0.513 to 0.693 g/cm^(3),the oven-dried density ranged from 0.535 to 0.725 g/cm^(3),and the air-dried density ranged from 0.556 to 0.756 g/cm^(3).All densities showed an increasing trend with increasing age and axial part,and increased significantly between1 and 2 years,and then increased steadily to stabilize.The oven-dried and air-dried shrinking ratio showed a decreasing trend with the increasing age and axial part,and decreased significantly between 1-2 years,and then decreased steadily,the latter fluctuating relatively more.The compressive strength parallel to grain ranged from 50.73 to 64.58 MPa,MOR ranged from 114.09 to 134.26 MPa,and MOE ranged from 8.45 to12.42 GPa,all of which showed an increasing-decreasing-increasing trend with increasing a

关 键 词：金佛山方竹 基础物性 竹龄 竹秆轴向部位 

分 类 号：S795.9[农业科学—林木遗传育种] S781.9[农业科学—林学] S785S727.15