芒秆皮层的SEM-EDXA研究(Ⅰ)

用SEM-EDXA法研究芒秆茎部皮层的形态、超微结构及矿质元素分布.结果表明,芒茎皮层外表面由纵向的条纹区和非条纹区交替排列而成;皮层纵切面中存在多孔结构及具层状细胞壁的横向管孔;皮层中存在不同结晶形态的Si化合物.芒茎皮层的形态及超微结构明显与甘蔗、麦草等的茎部皮层不同.芒茎皮层主要含C、O、Si、K等元素,Si元素含量高于50%,C元素含量低于4.0%;皮层中部的Si元素含量最高,外部及内部的Si元素含量稍低;皮下纤维及芒茎内部组织结构中的Si元素含量均为0.00%.皮层中的Si化合物主要是无机物.

Study on the Cuticle of Miscanthus Stem by Means of SEM-EDXA (part Ⅰ)

The morphologies and ultra-structure of the cuticle of Miseanthus stem and the distribution of mineral elements in it were studied by means of SEM-EDXA. The results showed that the outer-surface of the stern cuticle consists of two different regions alternatively, one with longitudinally parallel strips, and the other with non-strlp. The longitudinal sections are porous and there are some transversally tubular porosities with laminated cell wall. The silicides in the stem cuticle have different forms of crystalline. The morphologies and ultra-structure of the cuticle of Miseanthus stem are obvionslv distinct from that of sugarcane and wheat stem. The cuticle mainly contains four chemical elements, i.e. C, O, Si and K, the Si content is more than fifty percent, the C content is less than four percent. The Si content in the middle-part of the cuticle is the highest, and that in outer or inner-part of the cuticle is slightly lower. The Si content in the fiber underneath the epidermis or in the inner organs of the stem is 0.00%. It is obvious that the Si element plays a key role in the Miseanthns stem cuticle, and most of silicides in the cuticle will be inorganic in nature. It is to effectivel.v remove the Miscanthus stem cuticle for the substantially decreasing the silicon in black liquor of alkaline Miseanthus pulping.