造纸原料总结.pptVIP

造纸原料概述;Four Great Inventions of Ancient China ;Pre-Paper Media;Egyptians and Papyrus;Image of a papyrus plant;/~seidti/iam/tc_pap66.html;Manufacture of papyrus;It is also possible that the two layers were glued together. While still moist, the two layers are hammered together, mashing the layers into a single sheet. The sheet is then dried under pressure. After drying, the sheet of papyrus is polished with some rounded object, possibly a stone or seashell or round hard wood. ;It is widely accepted that Ts’ai Lun, a Chinese court official, invented paper in 105 AD. ; Ts’ai Lun’s Paper;Difference between paper and papyrus;原料？;原料是一切工业生产的基础。 造纸原料的基本要求 （一）原料质量要好 （二）原料资源要丰富、集中 （三）原料价格要低廉;造纸纤维原料的分类;Fibers for Papermaking;造纸纤维原料中的细胞;The cell is the basic structural and functional unit of all known living organisms. ;造纸纤维原料中细胞的功能;Conducting and supporting cells are elongated, axial cells (按轴向排列). In hardwoods, the conducting cells consist of vessel elements, and the supporting cells consist of fibers. In softwoods, tracheids perform both of these functions. Conducting cells and supporting cells are dead cells whose cell cavities are filled with water and air.;Storage cells consist of short, thin-walled parenchyma ([pE5reNkimE]) cells.;植物纤维原料中的细胞类型;The rays of softwoods are composed either of parenchyma cells alone or of parenchyma cells and ray tracheids.;Softwoods are simple and regular in their structure. Their wood substance is composed mainly of two kinds of cells: longitudinal ([lCndVi5tju:dinl]) tracheids ([treikiid]) and ray parenchyma ([pE5reNkimE]). Approximately 90-95% of the wood volume is occupied by the longitudinal tracheids.;Tracheids (or fibers) are needle-like cells which transport fluids through the tree and provides strength.;阔叶木原料中的细胞;Vessel cells are the principal water-conducting cell type of flowering plants ;韧皮纤维-Libriform [5laibrE7fC:m] fibers;纤维管胞—Fiber tracheids;导管（阔叶材）; 草类纤维原料中各种细胞形态如图 ;薄壁细胞;竹材原料中各种细胞形态如图 ;（二）纤维原料中纤维细胞的化学组成;重点思考和需掌握的问题