Using 3-year-old culms of 8 provenances of Bambusa chungii from Guangdong, Guangxi and Hainan Provinces, the indexes of wood properties, such as fiber dimensions and chemical composition were investigated and analyzed...Using 3-year-old culms of 8 provenances of Bambusa chungii from Guangdong, Guangxi and Hainan Provinces, the indexes of wood properties, such as fiber dimensions and chemical composition were investigated and analyzed by the methods of Analysis of variance and correlation coefficient to reveal the geographic genetic variation situation. The results showed that there are significant differences between fiber length, fibrin and 1% NaOH extraction contents of B. chungii from 8 provenances; moreover, the fiber length and fiber length/width ratio had a decreasing change pattern with geographic variation from the south to the north in altitude (from high to low in elevation). The heritabilities for fibrin, fiber length, 1% NaOH extractive, lignin and fiber length/width ratio were 0.7, 0.84, 0.54, 0.38 and 0.13, respectively. A significant negative correlation was found between 1% NaOH extraction, benzo-alcohol extraction contents and bamboo culm yield, whereas there was a significant positive correlation between fibrin contents and bamboo wood yield. Besides, a close correlation was detected between fiber dimensions indices and bamboo growth or bamboo wood yield. Finally, three provenances with high qualities and culm yield, i.e. Huaiji, Xinyi and Guilin, were selected as superior sources based on principal component analysis.展开更多
The influential factors of DQP bleaching, chlorine dioxide bleaching, chelation and hydrogen peroxide bleaching, of bamboo kraft pulp were studied. The pH value in D stage, dosage of EDTA in Q stage and charge of MgSO...The influential factors of DQP bleaching, chlorine dioxide bleaching, chelation and hydrogen peroxide bleaching, of bamboo kraft pulp were studied. The pH value in D stage, dosage of EDTA in Q stage and charge of MgSO4 in P stage were optimized. The results indicated that good results of chlorine dioxide bleaching were obtained under the conditions of ClO2 2.0%,pH 4, and the highest final brightness(86.4%ISO) and the lowest final Kappa number(1.37) were attained when the charge of EDTA in Q stage was 0.4%, charge of MgSO4 in P stage was 0.2%, and the other conditions of P stage : pulp consistency 10%, H2O2 charge 2.5%, NaOH charge 1.4%, temperature 90℃ and time 120 min. A comparison of bleaching results, pulp strength and effluent characteristics of bamboo kraft pulp between DQP and CEH sequences was done. The results indicated that bamboo kraft pulp could be bleached to brightness of above 83%ISO by both DQP and CEH sequences. Compared with CEH bleached pulp, DQP bleached pulp had slightly lower brightness, better brightness stability, higher pulp viscosity, better strength properties and lower pollution loads.展开更多
基金funded by both of the Interna-tional Tropical Timber Organization (ITTO), grant No. PD10/00. REV.2 (I,F)the National‘Tenth Five-year’Key Program of China, grant No. 2004BA506B0103
文摘Using 3-year-old culms of 8 provenances of Bambusa chungii from Guangdong, Guangxi and Hainan Provinces, the indexes of wood properties, such as fiber dimensions and chemical composition were investigated and analyzed by the methods of Analysis of variance and correlation coefficient to reveal the geographic genetic variation situation. The results showed that there are significant differences between fiber length, fibrin and 1% NaOH extraction contents of B. chungii from 8 provenances; moreover, the fiber length and fiber length/width ratio had a decreasing change pattern with geographic variation from the south to the north in altitude (from high to low in elevation). The heritabilities for fibrin, fiber length, 1% NaOH extractive, lignin and fiber length/width ratio were 0.7, 0.84, 0.54, 0.38 and 0.13, respectively. A significant negative correlation was found between 1% NaOH extraction, benzo-alcohol extraction contents and bamboo culm yield, whereas there was a significant positive correlation between fibrin contents and bamboo wood yield. Besides, a close correlation was detected between fiber dimensions indices and bamboo growth or bamboo wood yield. Finally, three provenances with high qualities and culm yield, i.e. Huaiji, Xinyi and Guilin, were selected as superior sources based on principal component analysis.
文摘The influential factors of DQP bleaching, chlorine dioxide bleaching, chelation and hydrogen peroxide bleaching, of bamboo kraft pulp were studied. The pH value in D stage, dosage of EDTA in Q stage and charge of MgSO4 in P stage were optimized. The results indicated that good results of chlorine dioxide bleaching were obtained under the conditions of ClO2 2.0%,pH 4, and the highest final brightness(86.4%ISO) and the lowest final Kappa number(1.37) were attained when the charge of EDTA in Q stage was 0.4%, charge of MgSO4 in P stage was 0.2%, and the other conditions of P stage : pulp consistency 10%, H2O2 charge 2.5%, NaOH charge 1.4%, temperature 90℃ and time 120 min. A comparison of bleaching results, pulp strength and effluent characteristics of bamboo kraft pulp between DQP and CEH sequences was done. The results indicated that bamboo kraft pulp could be bleached to brightness of above 83%ISO by both DQP and CEH sequences. Compared with CEH bleached pulp, DQP bleached pulp had slightly lower brightness, better brightness stability, higher pulp viscosity, better strength properties and lower pollution loads.