中文摘要：

该文利用原位成像纳米压痕技术研究了针叶材管胞细胞壁不同壁层之间在纵向弹性模量（MOE）和硬度方面的差异．结果表明，当压针从细胞壁的纵向压入时，细胞壁变形机制以塑性变形为主；细胞壁纵向弹性模量和硬度在细胞壁厚方向的分布不均匀．S3层与细胞腔交界处、S1层与复合胞间层（CML）交界处的弹性模量和硬度均明显小于次生壁（SW）S3层．此外，相邻管胞次生壁是层之间的弹性模量和硬度也存在一定差异．ANOVA分析表明，杉术管胞、马尾松管胞次生壁的弹性模量均显著大于复合胞间层，但两者之间的硬度差异不显著．虽然马尾松成熟材管胞次生擘的纵向弹性模量和硬度均大于幼龄材，但差异的程度不同．弹性模量前者比后者约大40％．但硬度只大13％．管胞次生壁和复合胞间层的弹性模量和硬度之间均存在较显著的正线性相关关系．

英文摘要：

In situ imaging nanoindentation was used to characterize the differences in longitudinal Modulus of Elasticity （MOE） and hardness of different cell wall layers of softwood tracheids, It was found that the deformation of cell wall was mainly plastic when tips were indented in longitudinal direction. The distribution of longitudinal MOE and hardness along cell wall thickness was uneven with much lower values at the interface between S3 layer and cell cavity as well as SK layer and compound middle lamella （CML） compared with that measured in S2 layer. There also existed differences in MOE and hardness between S2 layers of adjacent tracheids. ANOVA indicated significant differences in MOE between secondary wall （SW） and CML, but no significant difference for hardness. Both MOE and hardness of mature wood trachedis were larger than that of juvenile wood, but in a different degree. The SW of mature wood tracheids displayed an MOE nearly 1.4 times of that of juvenile wood, but only 13% harder than juvenile wood. A positive linear correlation between MOE and hardness was also found both for SW and CML of tracheids.