Tahereh gholizadeh; Arash Farajpour Roudsari; Asghar Tabei
Abstract
The purpose of this study was to compare the chemical compositions and biometric features of stem and cone fibers (length, diameter, and wall thickness) and the derived coefficients of loblolly pine (Pinus taeda) in Astara district, Gilan province. Discs from stem and cone were randomly taken and the ...
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The purpose of this study was to compare the chemical compositions and biometric features of stem and cone fibers (length, diameter, and wall thickness) and the derived coefficients of loblolly pine (Pinus taeda) in Astara district, Gilan province. Discs from stem and cone were randomly taken and the chemical compositions and biometric features were measured employing the TAPPI standard test methods andFranklinmacerating technique, respectively. The biometric coefficients were estimated as well. Statistical analyses of the results indicated that the average cellulose content in stem and the cone was 54.83% and 27.57%, respectively. Lignin was estimated to be 32.57% in the stem and 34% in the cone. Furthermore, extractives soluble in ethanol, acetone and water from stem wood were measured as 92%, 1.97% and 7.04% respectively. The relevant values for pine cone were 1%, 2.45% and 7.28%, respectively. According to the results of statistical analysis, there was 5% significant difference between the results measured from cones and the stem except for the slenderness ratio. Regarding the length, diameter, lumen diameter and flexibility factor, the P. taeda stem possesses a higher value compared with cone and the runkel ratio was higher in cones compared to stem.
Fardad Golbabaei; Hossein Hosseinkhani; Abolfazl Kargarfard; Amir Nourbakhsh; Reza Hajihassani
Abstract
The major engineering properties of Pinus taeda L. wood growing in different regions of Caspian forests (North of Iran) was determined. Test materials were selected randomly from Pinus teada tree plantation and the test specimens were prepared according to ASTM D-143 standard. Mechanical and physical ...
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The major engineering properties of Pinus taeda L. wood growing in different regions of Caspian forests (North of Iran) was determined. Test materials were selected randomly from Pinus teada tree plantation and the test specimens were prepared according to ASTM D-143 standard. Mechanical and physical properties were measured on both green and air-dried samples (12% moisture content). The results of the measurement were statistically analyzed based on randomized block design and factorial experiment. The influence of specimen locations at different stem heights was examined. Based on the results of this study, statistically significant difference of the measured properties was not observed between the samples collected from different regions. Toughness was not influenced by moisture content, but the compression strength perpendicular to the grain of wet and air-dry specimens was not similar. Mechanical properties of Pinus teada wood grown in Iran is generally of lower quality compare to those in their original habitat.
Physics and anatomy
Ahmad Jahan latibari; Fardad Golbabaei; Mohammad reza Amini
Abstract
Pinus teada, which was planted in Pelembera region, shows promising both in growth rate and adaptability. Even though the fiber geometry of P. teada wood in its native growth region is excellent, but for utilization of this wood in pulping, the knowledge of its technological characteristics especially ...
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Pinus teada, which was planted in Pelembera region, shows promising both in growth rate and adaptability. Even though the fiber geometry of P. teada wood in its native growth region is excellent, but for utilization of this wood in pulping, the knowledge of its technological characteristics especially fiber geometry is required.Two trees of this species were randomly selected from Pelembera forests plantation in Gilan and after felling were cut in smaller bolts and transferred to wood &paper research laboratory, research institute of forests and rangelands. Five cross-sections with the thickness of 15 cm were cut from each tree and the cross-sections were used for selection of samples. Fiber geometry measurement samples were prepared from every five annual rings and from each sample, springwood (early wood) and summer wood (late wood) sample were cut separately. Preparations of fiber geometry samples were according to procedure developed by Franklin (1954) and from each sample the dimension of 30 complete and unbroken trachieds was measured.Trachied length, diameter, cell wall thickness and lumen diameter was measured for different elevation in tree and different growth rings in cross-section.Dimension of 3,00 trachieds were measured totally.Average trachied length, diameter, lumen diameter and cell wall thickness of early wood were measured at 3.65mm, 38.97 mm, 28.94 mm and 3.72 mm respectively. Related values for late wood is as follow: trachied length 3.84mm; diameter, 35.54 /lm; lumen diameter, 22.96 mm; and cell wall thickness, 6.29 mn. Average annual growths were measured at 5.66 mm and late wood percentage at 24.13. Felting, flexibility and runkel coefficients were calculated at 97.96, 73.48, and 26.74 respectively. The result of this study indicates that all measured properties increases with increasing the height of tree and from center (pith) toward outer regions (bark). However all the measured values decreased at highest as well as outer locations.Statistical analysis indicated that the difference in measured properties at different heights of trees from center to the bark is significantly different at 1% level.
