Document Type : Research Paper
Authors
1 M.Sc., Wood and Paper Science and Technology Department, Science and Research Branch, Islamic Azad University, Tehran, Iran.
2 Assistant Prof., Wood and Paper Science and Technology Department, Science and Research Branch, Islamic Azad University, Tehran, Iran
3 M.Sc., Wood and Paper Specialist, Bojnord Voccational Traning, Bojnord, Iran.
4 Assistant Prof., Wood and Paper Science and Technology Department, Science and Research branch, Islamic Azad University, َAstara, Iran.
5 Wood and Paper Science and Technology Department, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Abstract
Samples were prepared from the native poplar species (Populus alba) grown in Mehnan, a region in Bojnourd at the ages 5 and 25 and the anatomical, biometrical and chemical characteristics of the samples sections in three directions (cross section, radial and tangential) of the tree were measured. Dioxan and Klason lignin were measured. Structural similarities in vascular cavities or impacted vessels in the form of binary, tripple or tetraploidy groups in juvenile and mature wood was observed primarily in radial direction. Fiber length and cell wall thickness variation in the juvenile and mature wood was significantly different and as the age of the tree increases, such difference is more significant. This point need to be considered by cellulose industries. As the age of the tree increase and the wood matures, significant change in vessel size in samples from 5 or 25 years old trees was not detected. The result showed that the older wood contains lower content of extractive and lignin and higher content of cellulose
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