The carbohydrate compositions of poplar I-214 and Chinese fir were investigated by the methods of hydrolysis and HPLC. The result showed that the contents of glucose, xylose and arabinose in poplar I-214 are higher th...The carbohydrate compositions of poplar I-214 and Chinese fir were investigated by the methods of hydrolysis and HPLC. The result showed that the contents of glucose, xylose and arabinose in poplar I-214 are higher than those in Chinese fir, while contents of rhamnose and mannose in poplar I-214 are lower than those in Chinese fir.展开更多
The variation of tensile strength parallel to grain in Chinese fir and I-214 poplar wood from plantations was studied in this paper. Aaccording to the national standards The Testing Methods for Physical and Mechanical...The variation of tensile strength parallel to grain in Chinese fir and I-214 poplar wood from plantations was studied in this paper. Aaccording to the national standards The Testing Methods for Physical and Mechanical Properties of Wood (GB 1927 to 1943 ? 1991), the small clear wood samples were cut and tested, which represent the south and north of trees with heights of 1.3, 3.3, 5.3 and 7.3 m. The results showed: the tensile strength parallel to grain of the north wood was higher than that of south wood. ANOVA shows that the tensile strength parallel to the grain with height is of significant difference (at 0.05 level).展开更多
Natural durability of two plantation woods, Chinese fir and I-214 poplar, was investigated thoroughly by three test- ing methods, namely an accelerated laboratory decay test, a fungus cellar test and a field test. Af...Natural durability of two plantation woods, Chinese fir and I-214 poplar, was investigated thoroughly by three test- ing methods, namely an accelerated laboratory decay test, a fungus cellar test and a field test. After the decay test using Postia pla- centa and Trametes versicolor, Chinese fir and the I-214 poplar showed 34% and 69% of mass loss, respectively, indicating they should be classified as slightly durable and non-durable wood. This conclusion was confirmed by the fungus cellar test and the field test. Like the performance in the decay test, I-214 poplar showed no resistance to termites either in the laboratory or in the field, whereas Chinese fir would be classified as moderately resistant.展开更多
Impregnation method can effectively improve physical and mechanical properties of wood. In this study, plantation poplar lumbers are impregnated by a low molecular weight phenol-formaldehyde resin solution with concen...Impregnation method can effectively improve physical and mechanical properties of wood. In this study, plantation poplar lumbers are impregnated by a low molecular weight phenol-formaldehyde resin solution with concentration of 30% under vacuum-pressure process, and then dried and machined according to the related standards. The results show that the physical and mechanical properties of poplar can be improved by the treatment, except for toughness. The average density of poplar increases from 0.397 to 0.710 g/cm3, the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain of treated specimens increase by 56.71%, 112.97% and 87.69%, respectively, compared to the untreated. And the hardness values on radial and tangential sections, and nail holding power as well as abrasion resistance of treated specimens improve by 283.87%, 82.78%, 71.43% and 22.06%, respectively; while toughness decreases by 48.80%.展开更多
This paper deals with the chemical components and the chemical structure of lignin of Chinese fir and Poplar I-214 from plantationforest. The results revealed that the contents ofchemical component in heart wood and s...This paper deals with the chemical components and the chemical structure of lignin of Chinese fir and Poplar I-214 from plantationforest. The results revealed that the contents ofchemical component in heart wood and sapwood were almost the same except ethanol-benzene extract both in Chinese fir and in Poplar I-214, The contents of ash, holocellulose, α -cellulose, pentosan, ethanol-benzene extract and cold-water extract in Poplar I-214 were higher than that in Chinesefir, The content of lignin in Poplar...展开更多
基金Supported by key foundation research project (G1999016001) of China and Japan International Cooperation Agency.
文摘The carbohydrate compositions of poplar I-214 and Chinese fir were investigated by the methods of hydrolysis and HPLC. The result showed that the contents of glucose, xylose and arabinose in poplar I-214 are higher than those in Chinese fir, while contents of rhamnose and mannose in poplar I-214 are lower than those in Chinese fir.
基金This work was supported by State Science and Technology Infrastructure Platform Projects (2004DEA70900).
文摘The variation of tensile strength parallel to grain in Chinese fir and I-214 poplar wood from plantations was studied in this paper. Aaccording to the national standards The Testing Methods for Physical and Mechanical Properties of Wood (GB 1927 to 1943 ? 1991), the small clear wood samples were cut and tested, which represent the south and north of trees with heights of 1.3, 3.3, 5.3 and 7.3 m. The results showed: the tensile strength parallel to grain of the north wood was higher than that of south wood. ANOVA shows that the tensile strength parallel to the grain with height is of significant difference (at 0.05 level).
基金Supported by Sino-Japanese Technical Cooperation Project Titled "Studies on Chinese Plantation Wood" (JICA PROJECT/033-1418-E-O)
文摘Natural durability of two plantation woods, Chinese fir and I-214 poplar, was investigated thoroughly by three test- ing methods, namely an accelerated laboratory decay test, a fungus cellar test and a field test. After the decay test using Postia pla- centa and Trametes versicolor, Chinese fir and the I-214 poplar showed 34% and 69% of mass loss, respectively, indicating they should be classified as slightly durable and non-durable wood. This conclusion was confirmed by the fungus cellar test and the field test. Like the performance in the decay test, I-214 poplar showed no resistance to termites either in the laboratory or in the field, whereas Chinese fir would be classified as moderately resistant.
文摘Impregnation method can effectively improve physical and mechanical properties of wood. In this study, plantation poplar lumbers are impregnated by a low molecular weight phenol-formaldehyde resin solution with concentration of 30% under vacuum-pressure process, and then dried and machined according to the related standards. The results show that the physical and mechanical properties of poplar can be improved by the treatment, except for toughness. The average density of poplar increases from 0.397 to 0.710 g/cm3, the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain of treated specimens increase by 56.71%, 112.97% and 87.69%, respectively, compared to the untreated. And the hardness values on radial and tangential sections, and nail holding power as well as abrasion resistance of treated specimens improve by 283.87%, 82.78%, 71.43% and 22.06%, respectively; while toughness decreases by 48.80%.
基金Japan International Cooperation Agency key foundation research project of China.
文摘This paper deals with the chemical components and the chemical structure of lignin of Chinese fir and Poplar I-214 from plantationforest. The results revealed that the contents ofchemical component in heart wood and sapwood were almost the same except ethanol-benzene extract both in Chinese fir and in Poplar I-214, The contents of ash, holocellulose, α -cellulose, pentosan, ethanol-benzene extract and cold-water extract in Poplar I-214 were higher than that in Chinesefir, The content of lignin in Poplar...