Physics and anatomy
Nooshin Toghraie
Abstract
One-year seedlings of five species of eucalypt: E. camaldulensis, E. microtheca, E. viminalis, E. globulus and E. gunnii were treated for 14 weeks in growth season, tilting a branch to c. 60° in every successful ones. We investigated the anatomical features of stems wood after 15 days and every 2 ...
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One-year seedlings of five species of eucalypt: E. camaldulensis, E. microtheca, E. viminalis, E. globulus and E. gunnii were treated for 14 weeks in growth season, tilting a branch to c. 60° in every successful ones. We investigated the anatomical features of stems wood after 15 days and every 2 weeks according to IAWA list of features afterwards.The results showed that tilted stems formed more tension wood in the form of gelatinous fibers than straight (untreated) ones. The formation of gelatinous fibers was considered to be closely related to tension wood formation. The formation of gelatinous fibers was considered to be closely related to tension wood formation. Excluding E. globulus, all the other species formed growth eccentricity and tension wood. Although the significant differences between the species and between different locations in the branches, there were no significant differences between the percent of tension wood among the species studied.
Nooshin Toghraie; Abdolrahman Hosseinzadeh; Davood Parsapazhoh; Fardad Golbabaei
Abstract
Peroxidases are enzymes which catalyse two final steps in the wood lignin biosynthesis. The connection between xylem peroxidase activities and wood xylem lignifications was examined by determining peroxidase activities in the stems of eucalypt (Eucalyptus camaldulensis Dehn.) trees during two seasons ...
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Peroxidases are enzymes which catalyse two final steps in the wood lignin biosynthesis. The connection between xylem peroxidase activities and wood xylem lignifications was examined by determining peroxidase activities in the stems of eucalypt (Eucalyptus camaldulensis Dehn.) trees during two seasons in 1999over the period of annual growth. In addition, samples from the same trees were examined for lignin content. This study clarifies the possible roles of this enzyme in lignin biqsynthesis and forms a background for further work on the last steps in lignin polymerisation. The peroxidase activity of some samples was lower in Autumn. But in the others there was a great increase in Autumn vs. Winter. Though in Autumn there were more isoenzyme. The results show a relation between lignifications and Peroxidase enzyme zones. In Eucalyptus camaldulensis Dehn. in khozestan.
Chemistry of wood
Nooshin Toghraie; Abdolrahman Hosseinzadeh; Davood Parsapazhoh; Fardad Golbabaei
Abstract
To study saxaul wood properties in the various ecological regions of Iran twelve 10-22 years old sample trees (4 trees from each species) were selected and cut from three different areas around kerman. Physical, chemical and anatomical characteristics of wood samples were investigated. The results of ...
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To study saxaul wood properties in the various ecological regions of Iran twelve 10-22 years old sample trees (4 trees from each species) were selected and cut from three different areas around kerman. Physical, chemical and anatomical characteristics of wood samples were investigated. The results of this investigation revealed that the initial moisture content before felling was 38.6% and the mean specific gravity based on oven dry weight and oven dry volume (WOD/VOD), oven dry and saturated weight Saxaul saturated volume (WOD/Vs ,WS/VS ), were studied for yellow, white and black and respectively. It is concluded that saxaul wood of Kerman province is heavy. The average longitudinal, radial and tangential shrinkage were surveyed. Wood periodicity of growth was determined to be 3-4 rings per year. Anatomical features were investigated by light microscopy and papermaking factors were determined. Fiber length, fiber diameter and lumen diameter were determined. These values lead to species with short and thick fibers. Chemical composition including percentage of cellulose, lignin, extractives and ash were revealed too.
Chemistry of wood
Nooshin Toghraie; Abdolrahman Hosseinzadeh; Khashayar Keimosa
Abstract
In this research, worked on two juniper trees (Juniperus exelsa L.) in Bakhtiari region as a part of Irano-touranian district. We noted the Sp. Gr. Of wood based on saturated volume 0.52, porosity 64%, volume shrinkage and swelling 10% and 11.3% resp. Anatomical structure and microscopic characteristics ...
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In this research, worked on two juniper trees (Juniperus exelsa L.) in Bakhtiari region as a part of Irano-touranian district. We noted the Sp. Gr. Of wood based on saturated volume 0.52, porosity 64%, volume shrinkage and swelling 10% and 11.3% resp. Anatomical structure and microscopic characteristics had been investigated incidentally. The average length of tracheids 1.3 mm. And the diameter, lumen diameter and thickness of cell wall of tracheids were determined 23.4, 16.3 and 3.5 microns resp. the major pulp indexes are calculated via related formulas.
Abdolrahman Hosseinzadeh; Nooshin Toghraie; Fardad Golbabaei; Nayeralsadat Sadraei
Abstract
In order to investigate The properties of wood eight-nineteen-years- old trees of Eucalyptus microtheca from De-hnow exprimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. From each tree, 10 cm thick cross-sectional discs at several ...
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In order to investigate The properties of wood eight-nineteen-years- old trees of Eucalyptus microtheca from De-hnow exprimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. From each tree, 10 cm thick cross-sectional discs at several different heights (3 metres intervals) were cut and together with remaining boles then transfered to the Alborz Research Center-Karaj for laboratory studies. The laboratory studies included determination of physical, anatomical and mechanical properties as well as chemical compositions of wood. The mechanical properties were evaluated on the ASTM samples for air-dry and green conditions. The following conclusions were drawn from this study:E. microtheca from one site in southern region of Iran has an average specific gravity of 0.804, fiber length of 0.811 mm, fiber diameter of 15.9 mm, lumen diameter of 5.7 mm, cell wall, thickness 5 mm, cellulose content of 44.47 percent.It was found that the mean values of modulus of rupture, modulus of elasticity and compression strength-parallel to grain tested at green condition were 72.50 MPa, 8066.6 MPa and 38.5 MPa and air-dried condition were 120.7 MPa, 12013.8 MPa and 69.80 MPa respectively.Data are also presented on other mechanical properties such as impact strength, nail withdrawal cleavage and et
Physics and Mechanical Wood
Abdolrahman Hosseinzadeh; Nooshin Toghraie; Fardad Golbabaei
Abstract
To determine major engineering properties of Hornbeam wood (Carpinus betulus L.) in Vaisar region of Caspian Forests (North of Iran), adopting ASTM (D-143) Standard specifications, the matched small clear specimens were prepared. The test materials were derived from three randomly chosen trees. Mechanical ...
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To determine major engineering properties of Hornbeam wood (Carpinus betulus L.) in Vaisar region of Caspian Forests (North of Iran), adopting ASTM (D-143) Standard specifications, the matched small clear specimens were prepared. The test materials were derived from three randomly chosen trees. Mechanical and physical properties were measured on two moisture states: green and air - dried (at 12% moisture content).The influence of locations of specimens in the height of tree trunks and geographical directions were tested on target properties. From the results of this study it could be concluded that, there were no significant differences between the various heights and geographical directions from the pith for most of the properties investigated.Toughness was not influenced by moisture content. The average value of hardness of Hornbeam wood in transverse sections were the same as side_grain sections in green condition, but air-drying caused increasing the value of cross - sections about 30% The compression strength perpendicular r to the grain showed differences in wet and dry conditions.
