摘要
为探究泡桐木材主要物理特征(生长轮宽度标准差、密度)以及主要化学组分对其声学振动性能影响的内在规律,本文采用传统的物理实验方法(参照木材密度测定方法 GB/T 1933-2009)和化学实验方法(参照木材综纤维素和酸不溶木质素含量测定近红外光谱法LY/T 2151-2013),测定泡桐的密度和主要化学组分(综纤维素、木质素、抽提物)的含量。利用多通道FFT分析仪对泡桐板材的声学振动性能参数动弹性模量、声阻抗、声辐射强度等进行测定,通过一元线性回归或二元线性回归方程分别分析木材主要生长轮宽度标准差、密度、不同化学组分含量与木材声学振动参数动弹性模量、声阻抗、声辐射品质常数的相关性及变化趋势,得出:对于泡桐乐器共鸣板选材时,泡桐木材生长轮宽度变异系数在3.0~5.5,且变异系数越小即生长轮宽度越均匀;密度在0.225 g/cm3时,泡桐木材的综纤维素含量约在75%,木质素的含量约在18%,1%Na OH抽提物约在20%时,其声学振动性能最好。
In order to explore the influence regular of wood growth ring width, variable coefficient, density and the main chemi-cal components of P. elongata on acoustic vibration p e r f o r m a n c e , the p aper used the traditional p hysical and ch e m i c a l e x p e r i m e n t methods to measure the main chemical components content of P. elongata（ holoce l l u l o s e , lign i n , a n d extract c o n t e n t ） . T h e acoustic vibration parameters including dynamic elastic modulus E , acoustic i m p e d a n c e ω a n d acoustic radiation d a m p i n g R w e r e m e a s u r e d u -sing the multi - channel fast Fourier transform analyzer. The correlation and variation trend between the wood growth ring width stand-ard deviation, density,different chemical components content and acoustic vibration parameters were analyzed by single or binary line-ar regression equation. The results showed that while choosing the P. Elongata i n s t r u m e n t s o u n d b o a r d , the variable coefficient of wood growth ring width was between 3. 0 to 5. 5, the smaller the coefficient, the more uniform the width. The vibration performance was the best while the density was about 0. 225 g/cm3, the holocellulose content was about 75% , the lignin content was about 18% and 1% NaOH extract content was about 20%.
出处
《森林工程》
2017年第4期34-39,共6页
Forest Engineering
基金
国家自然科学基金(31670559)
中央高校基本科研业务费专项资金项目(2572016EBJ1)
关键词
泡桐
宏观构造特征
主要化学组分
动弹性模量
声阻抗
声辐射品质常数
P. Elongata
ma c r o s c o p i c structure characteristics
m a i n c h e m i c a l c o m p o n e n t s
d y n a m i c elastic m o d u l u s
a c o u s -tic impedance
acoustic radiation damping
