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本文阐述了辽宁省草河口人工林红松木材纤丝倾角和管胞长度的变异规律及其与小试件拉伸强度的关系,并对应压材和正常材进行了比较。结果得出:晚材倾角与管胞长度与小试件拉伸强度成负相关,管胞长度与拉伸强度成正相关。同令期的纤丝倾角在应压材内平均较正常材者约大36.8％,长度约短21.7％,小试件拉伸强度约低18.7％。 在针叶树木材结构上,管胞是组成整个木材体积的绝对主要成分——约占90—95％。管胞长度、直径、壁厚等的变异,直接影响着木材的物理、力学性质。管胞次生壁是胞壁的主要部分,而次生壁中层(S_2)又占整个胞壁的70—90％,故此层对木材性质有着很大影响。40年代迄今,世界各国学者研究木材细胞壁多集中在次生壁中层的探讨上,原因即在于此。 次生壁中层纤丝倾角是决定木材性质指标之一,它影响着许多木材力学性质——如顺纹压力、拉伸、弯曲及顺纹剪力等,又是木材干缩的主要原因。国外对此早在1941年有Phillips、Kollmann等(1943)就美国西加云杉Sitka spruce和松树进行过研究,继之Killer(1954)、Echolls(1955)就沼泽松Slash pine;Jurbergs。(1963)、Hatris(1965)、Cave(1966)及Meylen(1967)均进行过详尽的研究。Meylen等(1969)用x—线衍射法测量,并与直接测定比较,得出两种方法间有一良好的线?
In this paper, the variation rules of the dip angle and tracheid length of Pinus koraiensis wood in the artificial grassland of Caowei Estuary in Liaoning Province and its relationship with the tensile strength of small test pieces were compared. The results showed that the inclination angle of late material and tracheid length were negatively correlated with the tensile strength of small specimens, and the length of tracheids was positively correlated with the tensile strength. With the same period of fibrillation inclination in the material should be averaged about 36.8% larger than the normal material, the length of about 21.7% short, the tensile strength of small specimens about 18.7% lower. In the coniferous wood structure, tracheids are the absolute major components that make up the entire volume of the wood - about 90-95%. Tracheid length, diameter, wall thickness and other variations, a direct impact on the physical and mechanical properties of wood. The tracheid secondary wall is the main part of the cell wall, and the secondary wall (S_2) accounts for 70-90% of the entire cell wall, so this layer has a great influence on the wood properties. Since the 1940s, scholars from all over the world have studied the reason why the majority of the wood cell walls are concentrated in the secondary wall. Secondary wall fibrillation angle is one of the indicators that determine the nature of the wood, which affects many mechanical properties of wood - such as the grain pressure, stretching, bending and grain shear, which is the main cause of wood shrinkage. Foreign Phillips abroad as early as 1941, Kollmann et al. (1943) conducted a study on Sitka spruce and pine trees in the United States, followed by Killer (1954) and Echolls (1955) on Slash pine; Jurbergs. (1963), Hatris (1965), Cave (1966), and Meylen (1967). Meylen et al. (1969) measured x-ray diffraction and compared it with the direct measurement to find a good line between the two methods.