利用SilviScan系统测量了美国白橡(Quercus alba)与红橡(Quercus rubra)不同年轮木材的微纤丝角和密度，并计算得到相应的纵向弹性模量值。红橡木材样品的弹性模量平均值为16.34 GPa，高于白橡的(13.11 GPa)，并且从心材到边材方向上无明显的变化。而白橡木材样品中由于幼龄材的存在，距离髓心40 mm范围内，弹性模量值较低，相应的微纤丝角的值较高；从40 mm处到树皮方向变化不显著。沿所测量的径向方向45个年轮范围内，红橡木材样品的微纤丝角明显低于白橡木材样品。
Abstract
The microfibril angle (MFA) and wood density of white oak (Quercus alba) and red oak (Quercus rubra) were measured by SilviScan system, the elastic modulus (MOE) being also calculated. The mean value of MOE in red oak (Quercus rubra) sample was 16.34 GPa higher than white oak (Quercus alba) sample (13.11 GPa). There was no significant difference of MOE in red oak from pith to bark. However, white oak sample showed high MOE and MFA for the first 40 mm, which probably corresponded to juvenile wood; from 40 mm position to bark direction the change was not distinct. The value of MFA was lower in red oak than in white oak along radial direction within the measured 45 growth rings.
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基金
收稿日期：2008-07-21修回日期：2009-05-12基金项目：国家“十一五”科技支撑计划(2006BAD07A07-04)作者简介：吴燕(1979—)，博士生。*周定国(通讯作者)，教授，研究方向为木材科学与技术。Email: zhoudg@njfu.edu.cn。引文格式：吴燕,周定国,王思群,等. 木材微纤丝角和密度与弹性模量的关系[J]. 南京林业大学学报:自然科学版,2009,33(4):113-116.
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