مقالات رزومه مهندس مجتبی رضانژاد دیوکلائی

Investigating changes in biometrics and anatomy of wood species in different parts of tree stems is one of the issues that have been of long interest to researchers in the wood and paper industry. In this study, a comparison of the anatomical and biometrical characteristics of heartwood and sapwood Elaeagnus angustifolia was made. For this purpose, a completely healthy tree native to Khorasan Province, Iran was selected and cut. Test specimens with dimensions of 2 × 2 cm and a length of 3 cm sequentially taken from near the pith (heartwood) to near bark (sapwood) were prepared for biometric and anatomical experiments. Biometric characteristics including fiber length, fiber lumen diameter, fiber diameter and cell wall thickness were evaluated. The results showed that the effect of different parts of the stem on the biometric characteristics of the fibers at the upper level was significant, so that biometric properties had an increasing trend as they moved away from the pith area and neared the bark area. Microscopic studies of wood close to the bark of the elaeagnus angustifolia showed that this species is of the ring porous hardwood species, with distinct growth ring, simple perforation plates and scalariform, alternate intervessel pits and presence of Tyloses.

The purpose of this study was to investigate the biometric, anatomical and physical characteristics of plum wood and its applicability in the wood and paper industry. For this aim, three completely healthy plum trees were selected and cut from citrus orchards located in Mazandaran Province. Three discs of 5 cm thickness at three heights (breast height, 3 m height, and 4.5 m height) were cut from the tree trunk in transverse direction and the test specimens were 2 cm × 2 cm × 3 cm- long from the pith to the bark and cut consecutively for examination. Fiber biometric properties including fiber length, fiber lumen diameter, fiber diameter, and cell wall thickness were evaluated. Physical properties including oven-dry density and basic density were calculated. Microscopic sections (transverse, tangential and radial) were prepared and evaluated in accordance with the list of the International Association of Anatomists of the World (IAWA) to study anatomical features. Examination of the anatomy of the plum tree showed that this wood is a semi ring porous hardwood that has distinct growth ring, heterogeneous rays, simple perforation plates, alternative intervessel pits and helical thickenings in vessel elements. In addition, the results of the plum tree biometrics showed that the biometric properties of the fibers in the radial axis of the stem from the pith to the bark follow an increasing pattern, so that the maximum fiber length at the breast height in the area close to the bark averages 1.23 mm and its lowest value at a height of 4.5 m in the area close to the pith was calculated to an average of 0.62 mm. However, in the longitudinal axis with increasing height from the trunk to the crown of the tree, a downward pattern was observed. The results showed that the oven-dry density and basic density from the pith to the bark of the tree had an upward trend and from the bottom of the tree to the crown of the tree had a downward trend.

In this study, the possibility of making gypsum-based boards from rice straw chips with different levels was investigated. Variable factors in this study were considered in nano at three levels of 0, 3 and 7% and also the ratio of mixing rice straw to gypsum at three levels ( 5:95 , 10:90 , 15: 85 %). Thus, with the consideration of nine treatments, a total of 27 laboratory boards were constructed. The specific mass of the first target 1.10 gr/cm3 was considered. Mechanical and physical properties of composites include modulus of rupture, modulus of elasticity, internal bonding, water absorption after 2 and 24 hours of immersion, and density of boards according to standard (DIN-EN-634) and fire resistance (weight loss percentage) they were measured according to a standard ISO-11925. In order to investigate the common chapter of rice straw and gypsum as well as the distribution of nano-wollastonite, microscopic images (SEM) of the fracture surface of the samples were prepared and the results showed that the composites made with nano-wollastonite had higher mechanical and physical strengths. Microscopic imaging (SEM) showed that the boards made with 7% nano had stronger internal connections and created a uniform structure. In this study, composites made of 7% nano wollastonite with 5% rice straw were selected as the optimal treatment.

In this study, we investigated the biometrical properties of fibers, the physical and microscopic properties of Morus alba wood. For this purpose, three healthy mulberry trees were randomly selected and cut in Babol city (Mazandaran province). Three discs of 5 cm thickness were prepared at breast height, 3 m height, and 4.5 m height. In the transverse direction, the test specimens were cut 2 × 2 cm to 3 cm from the pith to the bark sequentially and examined. Then the biometric properties of fibers including fiber length, fiber lumen diameter, fiber diameter, and cell wall thickness were measured. Also, microscopic sections of wood close to the pith and bark were studied using light microscopy according to the List of International Association of Wood Anatomists (IAWA). Anatomy of the wood near the pith and bark of the Morus alba tree revealed differences. Vessel grouping and its arrangements near the pith were more radially, while these features were more clustered near the bark. Rays in the area of the pith were more heterogeneous, while near the bark, many rays were homogeneous. The mean tangential vessel diameter near the larger bark (237 microns) was greater than that of the near-pith wood (144 microns). The porosity of wood was observed to be ring porous, near the bark, and semi ring porous near the pith. The results also showed that there was a significant difference in both the transverse and longitudinal directions of the Morus alba tree in terms of length, fiber diameter, fiber lumen diameter, and the cell wall thickness. The biometric properties of the fibers increased from the pith to the bark. The mean length, total diameter, fiber lumen diameter and cell wall thickness of the fibers were 1.51 mm, 27.25 µm, 18.74 µm, and 8.5 µm, respectively.

The purpose of this study was to investigate the anatomical and biometrical characteristics of the Platanus Sycamore tree (Plane tree) in the longitudinal and transverse axis of the stem. For this purpose, a completely healthy Plane tree with an approximate age of 12 years located in Amol city was randomly selected and cut. Two discs 5 cm thick from diameter at breast height and close to the crown of the tree was prepared. Then test specimens with dimensions of 3 × 2 × 2 cm consecutively in the transverse direction of the discs from the brain to the skin and the case were examined. Fiber biometry, fiber length, fiber lumen diameter, cell wall thickness and fiber diameter were evaluated. The results showed that longitudinal and transverse axis of the trunk significantly affect fiber on biometric features. The length of fibers, fiber lumen diameter, cell wall thickness and fiber diameter in the radial axis of the pith towards the skin increased and in the long axis of the lumber toward the crown decreased. Anatomical characteristics of sycamore Three transverse, tangential and radial cross sections showed that this wood is a diffuse porous hardwood species, distinct growth ring, Simple perforation plates with scalariform and opposite Intervessel pittings.

In this study, biometrics, physical and microscopic properties of Ficus carica wood were investigated. Therefore, three healthy Ficus carica trees in Mazandaran province have been selected and cut. Three discs of 5 cm thickness were prepared along the tree (diameter at breast height, 1.9 m height and near the crown). In the transverse direction, 2 × 2 × 2 cm test specimens were sequentially taken from the pith to the bark and examined for physical and biometric properties of the fibers. Then the biometric properties of fibers including fiber length, fiber lumen diameter, fiber diameter and cell wall thickness were measured. Physical properties including basic density, oven dry density, longitudinal shrinkage, radial shrinkage and tangential shrinkage were calculated. Microscopic sections of three surfaces (transverse, tangential and radial) of Ficus carica tree was prepared and the anatomical characteristics of the wood of this species were determined precisely and indexed by IAWA. Anatomical studies near the pith and bark of this wood revealed differences. The most important of these differences are the presence of Tyloses in the vessel lumen near the pith and the absence of it in the near bark, homogeneous rays near the bark and heterogeneous rays in the near pith, the mean tangential vessel diameter near larger bark (105 μm) than near pith (70 μm) and wood rays were wider near the bark than near the pith. Also Ficus carica tree was diffuse porous hardwood species, distinct growth ring, Axial parenchyma vasicentric and Banded, Simple perforation plates Intervessel pits alternate and containing prismatic crystals in parenchyma. The results showed that there were significant differences in both the transverse and longitudinal directions of Ficus carica tree in terms of fiber length, fiber lumen diameter, fiber diameter and cell wall thickness. As biometric properties of fibers increased from pith to bark.