The thermal degradation and charring of both larch lignin and manchurian ash lignin in the condensed phase were comparatively investigated by using TGA, FTIR and XPS. TGA experimental results showed that larch lignin produced more char residue than manchurian ash lignin under pure nitrogen at high temperature. This demonstrated that the carbon backbone of larch lignin was more stable than of manchurian ash lignin. This is attributed to more carbon_carbon bonds existing in larch lignin than in manchurian ash lignin. Under air condition, the lignin completely was decomposed to form volatiles at high temperature. There was no char residue in either larch lignin or manchurian ash lignin. This was because oxygen catalyzed the oxidative reactions of C-C and C-H bonds, which is supported by FTIR. FTIR and XPS data indicated that the cleavage of aliphatic ester bonds took place mainly under pure nitrogen, and more aromatic rings remained in the condensed phase. Manchurian ash lignin showed a high crosslinking rate based upon the relative intensity of C1s and C1s (C-C) and an obvious increase of the ratio of carbon to oxygen. Different thermal degradation of both larch lignin and manchurian ash lignin under pure nitrogen and air has been proved by TGA, FTIR and XPS.

According to the data of tracheid length, micro fiber angle, air density, ring width and late wood percentage, with the analysis of optimum method of classification, the boundary line of juvenile wood and mature wood of planted Chinese fir (Cunninghamia lanceolata) was determined as the 14th year. Based on the variation pattern of these parameters, the prediction equations were established. Wood quality prediction can be realized by these equations. By error analysis between the values of measured data and the values of prediction data, it is found that the results of wood prediction of planted Chinese fire are satisfactory.

本研究针对大兴安岭火烧原木中的以云杉小黑天牛（Monochamussutor L.）为主的虫害的严重性，进行了熏蒸法杀虫试验，通过试验，证明此种方法较好，优于喷淋法。文中还研究了充实率、时间、温度和湿度对熏蒸杀虫效果的影响，以及害虫对药剂抵抗力的差异，最后确定了合理的施药量和熏蒸时间。

分析和讨论了椴木单板经氢氧化钠溶液预处理后其胶合板的胶结强度提高的机理。本试验采用了浸液高度法测定了经氢氧化钠溶液预处理或未经预处理的椴木单板表面润湿性；利用研究用万能显微镜观察了预处理前后椴木导管分子和木纤维细胞壁的形态变化；借助于化学分析光电子能谱仪（ESCA）、红外和傅里叶变换红外光谱仪（IR和FTIR）探查了单板表面化学结构的变化。结果表明，经氢氧化钠溶液预处理后椴木单板表面的润湿性提高；木材细胞壁厚度明显增大；单板表面的疏水性抽提物迁移，氧碳比率增加。这些表面物理和表面化学性质的变化，均有利于改善胶合环境和提高界面胶结强度。