Ali Hasanpoor tichi; Fardad Golbabaei; Mojtaba Rezanezhad
Abstract
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 %). ...
Read More
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.
Composite wood products
ali hasanpoor tichi; Fardad Golbabaei; hadi Ghasemi; mojtaba rezanezhad
Abstract
In this study, the effect of nano gel wollastonite on physical, mechanical and morphological properties of composites made of bagasse and cement has been investigated. The mixing ratio of bagasse as lignocellulosic material with Portland cement at three levels (15:85, 25: 75 and 35: 65%) and nano-wollastonite ...
Read More
In this study, the effect of nano gel wollastonite on physical, mechanical and morphological properties of composites made of bagasse and cement has been investigated. The mixing ratio of bagasse as lignocellulosic material with Portland cement at three levels (15:85, 25: 75 and 35: 65%) and nano-wollastonite at three levels of 0, 3 and 7% were considered as the variables of this study. The cake density of all boards were 1.1 g / cm3 and calcium chloride booster 5% for all treatments were considered as constant factors. Mechanical and physical properties of the specimens include modulus of rupture, modulus of elasticity, internal bonding, thickness swelling after 2 and 24 soaking hours in water and density of boards according to DIN-EN-634 and fire resistance (weight loss percentage) according to standard ISO-11925 were measured. In this study, the hydration temperature of a mixture of cement, bagasse and nano-wollastonite was measured using a thermocouple and flux. Also, microscopic images (SEM) of samples were prepared to investigate the morphological properties of composites and their distribution. The results showed that by increasing the amount of nano-wollastonite, the percentage of weight loss boards decreased, the heat of hydration and the physical and mechanical properties improved. The modulus of rupture, modulus of elasticity, and internal bonding of boards decreased with increasing bagasse content and the maximum value was obtained using 15% bagasse. The results also showed that with increasing bagasse content in boards, there was a significant increase in thickness swelling of boards. Inference from microscopic imaging (SEM) showed that the optimum level of nano-wollastonite can fill the empty holes and create a uniform structure and thus improve the properties of the boards.
Physics and anatomy
ali hasanpoor tichi; mojtaba rezanezhad
Abstract
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 ...
Read More
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.
