【目的】以樟科的珍贵木材的樟木和楠木作为研究对象，探讨2种结构相近木材的有效识别方法。【方法】通过光学显微镜和傅立叶红外光谱对二者的解剖结构、红外光谱特征分别进行了比较研究。【结果】2种木材样本的显微结构特征较为相似，差异主要体现在樟木半散孔至散孔材，楠木为散孔材；樟木与楠木管孔平均弦径为（114.5293±31.5645）μm、（106.3788±19.6872）μm，樟木作为半散孔材平均弦径变化范围比楠木广。通过对6个木材样本的红外光谱比较，产地对樟木和楠木2种木材的红外光谱区域的指纹图谱有一定影响；2种木材的一维红外图谱峰形和出峰位置差异较小，仅在表征纤维素和半纤维素中C-O伸缩振动区域有所区别，樟木在波数1055 cm-1和1039 cm-1处形成了峰强度不等的双峰，楠木该位置只形成了波数1054 cm-1的一个不对称单峰；以1510 cm-1峰作为内标峰，与1595 cm-1（樟木）、1599 cm-1（楠木）的比值分别为1.1612和0.9969，说明樟木的木素中愈疮木基比例较高；樟和楠木的木材在波数800~1800 cm-1范围内的二阶导数谱差异明显，主要体现在吸收峰的数量和形状上，樟木的吸收峰可以分为17组峰簇，而楠木为17个独立吸收峰，全图谱的匹配度只有37.5。【结论】分析产地因素，波数900~3400 cm-1区域为木材图谱特征稳定的区域，可用于2种木材的图谱区分；在1055 cm-1和1039 cm-1范围内吸收峰的形状、1595 cm-1（樟木）和1599 cm-1（楠木）和1510 cm-1峰的相对强度比，可以作为2种木材一维图谱的种间识别特征；2种木材的二阶导数图谱差别较大，可用于2种木材的区分。%Objective]The aim of the this paper was to establish an identification method for 2 woods (Cinnamomum camphora and Phoebe zhennan) with similar structure.[Method]Optical microscope and fourier transform infrared spectrometer (FTIR)were used in this study and anatomical structure and infrared spectroscopy characteristics were compared between the two woods.[Results]C. camphora and P. zhennan showed similar microstructure . C . camphora belonged to semi- diffuse- porous wood or diffuse-porous wood while P. zhennan belonged to diffuse-porous wood. The variation of C. camphora tangential diameter of pores was greater than that P. zhennan with average tangential diameter of (114.529 3±31.564 5)μm and(106.378 8±19.687 2)μm,respectively. According to FTIR comparison of 6 wood samples, the origin of woods have certain effects on finger-print FTIR. The infrared spectrum of two woods had a little difference in the peak shapes and peak positions, with distinction of C-O stretching vibration in cellulose and hemicellulose. The twin peaks of different peak intensity of C. camphora existed at 1 055 and 1 039 cm-1 while the asymmetric unimodal peak of P. zhennan existed at 1 054 cm-1. Taking the 1 510 peak as an internal standard peak,the rate of 1 595 cm-1(C. c amp hora) and 1 599 cm-1(P. zhennan)was 1.161 2 and 0.996 9,respectively,indicating that the C. camphora had a high ratio of guaiacyl group. The obvious differences in the second-derivative spectroscopy between C. camphora and P. zhennan was observed in the range of 800 cm-1 and 1 800 cm-1,which mainly existed in the number and shape of absorption peaks. The absorption peaks of C. c amp hora could be divided into 17 groups of peak cluster while P. zhennan with 17 independent absorption peaks,which only had 37.5 of matched-degree in the whole spectrum. [Conclusion]Based on the origin place,the stable FTIR between 900 and 3 400 cm-1 was used to characterize these two woods. The absorption shape of 1 055~1 039 cm-1 and relative intensity ratio of absorption peak of 1 595 cm-1(C. camphora),1 599 cm-1(P. zhennan)and 1 510 cm-1 may be used to characterize these two woods. The second-derivative spectroscopy could be used to identify the two woods with obvious difference.
展开▼
