In Iran, due to abundant restrictions on harvesting wood from northern forests by implementing the preservation project and also lack of possibility for sufficient wood production, development of the area of planting ...In Iran, due to abundant restrictions on harvesting wood from northern forests by implementing the preservation project and also lack of possibility for sufficient wood production, development of the area of planting poplar is quite inevitable. Poplar wood properties have special importance to produce many wood production, particularly pulp and paper. Paper factories are the major consumers of poplar wood at the global level and this is because of unique morphological, physical, mechanical and technological properties of poplar wood. Therefore, regarding the importance of using this species in making various printing and writing paper, packaging or carton, cardboard and newsprint, in this study, costs of poplar production in one hectare including planting and harvesting were examined and determined. Then, based on conversion coefficients of FAO, required round wood, productivity and the cost of poplar wood were calculated for the producing various kinds of paper. The results indicate that carton and cardboard paper or packaging allocate the lowest cost and highest return, while printing and writing paper had highest cost and lowest return in terms of poplar wood supply needed for paper production.展开更多
In this paper, modal colloidal substances (MCS) were employed to study the effects of in-process colloid on the properties of newsprint. The adsorption of MCS on fibers and optical and physical properties of newsprint...In this paper, modal colloidal substances (MCS) were employed to study the effects of in-process colloid on the properties of newsprint. The adsorption of MCS on fibers and optical and physical properties of newsprint were both investigated with and without retention systems including agglomerating agent and flocculent. Results showed that MCS could be absorbed on the fibers without retention system, and retention systems could promote the MCS retention efficiency while the physical properties of sheets was affected by blocking the formation of hydrogen bonding between fibers and the surface tension of water and density of paper展开更多
文摘In Iran, due to abundant restrictions on harvesting wood from northern forests by implementing the preservation project and also lack of possibility for sufficient wood production, development of the area of planting poplar is quite inevitable. Poplar wood properties have special importance to produce many wood production, particularly pulp and paper. Paper factories are the major consumers of poplar wood at the global level and this is because of unique morphological, physical, mechanical and technological properties of poplar wood. Therefore, regarding the importance of using this species in making various printing and writing paper, packaging or carton, cardboard and newsprint, in this study, costs of poplar production in one hectare including planting and harvesting were examined and determined. Then, based on conversion coefficients of FAO, required round wood, productivity and the cost of poplar wood were calculated for the producing various kinds of paper. The results indicate that carton and cardboard paper or packaging allocate the lowest cost and highest return, while printing and writing paper had highest cost and lowest return in terms of poplar wood supply needed for paper production.
文摘In this paper, modal colloidal substances (MCS) were employed to study the effects of in-process colloid on the properties of newsprint. The adsorption of MCS on fibers and optical and physical properties of newsprint were both investigated with and without retention systems including agglomerating agent and flocculent. Results showed that MCS could be absorbed on the fibers without retention system, and retention systems could promote the MCS retention efficiency while the physical properties of sheets was affected by blocking the formation of hydrogen bonding between fibers and the surface tension of water and density of paper
