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 ...
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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.
Physics and anatomy
Farshid Basiji; Vahid reza Safdari; Ahmad Jahan latibari; Amir Nourbakhsh
Abstract
The objective of adding reinforcing fillers, such as natural fibers to plastics is to increase the strength compared with neat plastic and wood. In this research the effect of wood pulp fiber length (short, medium and long), aspect ratio and fiber content (27%, 37%, 47% and 0% (non-reinforced PP)) with ...
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The objective of adding reinforcing fillers, such as natural fibers to plastics is to increase the strength compared with neat plastic and wood. In this research the effect of wood pulp fiber length (short, medium and long), aspect ratio and fiber content (27%, 37%, 47% and 0% (non-reinforced PP)) with 3% maleic anhydride grafted polypropylene on wood plastic composites (WPCs) has been studied. Results showed that increased fiber length or aspect ratio and fiber content increases mechanical properties (tensile strength, tensile modulus and MOE). Impact strength had an inverse correlation with fiber content and fiber length, but fiber content was a much more important factor than fiber length for impact strength. The impact strength of composite of softwood pulps was much higher than wood floor composite plastic. The significant interaction between fiber length and fiber content, and the lack of a specific trend in the treatments made assessment of the effect of fiber properties on MOR difficult.
Physics and anatomy
Vahid Safdari
Abstract
The suitability of wood and noon-wood species for using in pulp and paper industry can be predicted by their morphological and chemical characteristics. In these research morphological and chemical properties of four spices of Ulmacea family, Ulmus glabrar, Ulmus compestris, Zelkova carpinifolia and ...
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The suitability of wood and noon-wood species for using in pulp and paper industry can be predicted by their morphological and chemical characteristics. In these research morphological and chemical properties of four spices of Ulmacea family, Ulmus glabrar, Ulmus compestris, Zelkova carpinifolia and Celtis australis have been compared. From each species three cross section, 5 cm thickness has been selected. Wood slivers of tree zones: near to pith, middle part and near to bark wood have been macerated in mixture of acetic acid and hydrogen peroxide at 60°C for 48 hours. Biometric coefficients of fibers in three zone and four species have been measured and analyzed by factorial, complete randomized block design. Result showed that, Zelkova carpinifolia has least lignin, ash and extractives and highest cellulose. The fibers of, Zelkova carpinifoliahas has highest Slenderness ratio, Runkel ratio and hence in Ulmacea family is most suitable species for paper industry. Fiber length, wall thickness in near to bark zone in comparison to near to pith was higher significantly. Therefore it is predicted that the mechanical properties of pulp of this three zones are different
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.
Physics and anatomy
Vahid Safdari
Abstract
Understanding of many wood technological features depends on anatomical characteristics which, unfortunately, researchers in Iran have not focused on recently. There are many trees and shrubs in the desert areas of Dasht-e Kavir and Dasht-e Lut with unstudied woody anatomical features. We studied one ...
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Understanding of many wood technological features depends on anatomical characteristics which, unfortunately, researchers in Iran have not focused on recently. There are many trees and shrubs in the desert areas of Dasht-e Kavir and Dasht-e Lut with unstudied woody anatomical features. We studied one of these species, Calligonum comosum (Polygonaceae). Three mature shrubs were selected and small cubic samples of woody stem and root were taken. Micro-sections were obtained with micro-tome and after dying with Astra-blue and Safranin the sections were mounted in Canada balsam. The results showed that many differences between roots and stems exist, such as distinct growth rings in the stems and indistinct rings in the roots, the presence of gums in the stems and absence in the roots, and lower ray width of the stems compared to the roots, inherent characteristics that have been reported by many other researchers. The most important difference between Calligonum comosum’s roots and stems is parenchyma-like fibers in the thin-walled roots which cannot be distinguished from axial parenchyma. The ground tissue of woody roots is parenchymatous cells full of starches, which probably can be related to the drought situation of deserts. The bark of Calligonum comosum has priderm and sclereid cells which make the bark stiff and hard. Also the result of particleboard of fabricated of Calligonum comosum’s wood showed that boards has at least technical characteristics of European Standard EN 312 and hence the silviculture of this species for stooping of erosion of soil and is suitable species for desertification and its wood can be used for producing of wood based panel.
Physics and anatomy
Babak Nosrati; mohamad haghpanah; masih masoudifar; alireza dorostkar
Abstract
In this research microscopic properties of wood near the pith to bark in Dalbergia sissoo was investigated. For this reason 3 stands of 10 years old Dalbergia sissoo trees from ShoshDanial area in Khozestan province were selected and cut. For measuring fiber biometrics of samples, from each trees one ...
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In this research microscopic properties of wood near the pith to bark in Dalbergia sissoo was investigated. For this reason 3 stands of 10 years old Dalbergia sissoo trees from ShoshDanial area in Khozestan province were selected and cut. For measuring fiber biometrics of samples, from each trees one disc and from each disc 10 pell in match's size segregated and tested. Segregation of fibers was done with Franklin method. Also microscopic segments of wood near the pith and bark were studied with light microscope. The results showed that the length, total and lumen diameter, and thickness of cell wall are significantly different and this values were increased from pith to bark. Ray widths and vessel diameters in wood near the pith and bark were 36.15, 132.98 and 31.82, 98.26 µm respectively and showed a significant difference in the level of 5%. The average number of vessels and the number of rays in wood near the pith and bark were 3.46, 7.20 and 3.54, 6.68 number respectively. Also ray length means in wood near the pith and bark were 130.86 and 132.05µm respectively and didn’t show a significant difference in the level of 5%.
Physics and anatomy
vahidreza safdari; shadman Pourmosa
Abstract
The Avicennia tree genus was named in honor of Ibn Sina, a 10th century Persian philosopher and physician known more commonly as Avicenna. In this paper wood anatomical property of Avicennia marina (Acanthaceae) which is one of the most important species of Iranian Mangrove forest has been investigated. ...
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The Avicennia tree genus was named in honor of Ibn Sina, a 10th century Persian philosopher and physician known more commonly as Avicenna. In this paper wood anatomical property of Avicennia marina (Acanthaceae) which is one of the most important species of Iranian Mangrove forest has been investigated. Wood samples were taken from trunk of three adult trees, and and micro -sectioned and dyed by Astrablue and Safranin O and finally mounted by Canada balsam. Also Wood chips (match size) were placed in equal parts of glacial acetic acid and hydrogen peroxide and were put in the oven at 60°C for 48 hours, then counted and stained on microscope slides. The presence of concentric included phloem which is surrounded by lignified conjunctive parenchyma (axial parenchyma) and scleroid bands are the most important anatomical characteristics of Avicenna marina. The variability of anatomical characteristics of Avicennia marina in different references can be attributed to grwoing site condition (altitude and latitude).
Physics and anatomy
ahmad saraiyan; soodeh zhand
Abstract
In this study, the effect of boiling water pre-treatment on yield, optical, physical and mechanical properties of NSSC (Neutral Sulfite Semi Chemical) pulp from Zagroos wheat straw (Golestan province) was investigated. Chopped wheat straw was pretreated in boiling water for 30 minutes, water to straw ...
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In this study, the effect of boiling water pre-treatment on yield, optical, physical and mechanical properties of NSSC (Neutral Sulfite Semi Chemical) pulp from Zagroos wheat straw (Golestan province) was investigated. Chopped wheat straw was pretreated in boiling water for 30 minutes, water to straw ratio of 10:1. NSSC pulping was carried out at constant pulping conditions including liquor to straw ratio of 10:1, maximum pulping temperature of 160ºC and 30 minutes pulping time. In order to study the effect of NaOH on strength properties of paper, in some trails only Na2S03 were used. Pulping was followed by defibration in laboratory refiner to reach 380±25mlCSF freeness. Handsheets at 60gr/m² were made from each pulp. The strength properties were determined on the basis of TAPPI standard. Results show that pre-treatment imparted a significant increasing effect on the strength properties of papers such as tensile, burst, breaking length, stiffness and density, except RCT strength. Increasing the chemical charge specially NaOH improved the pulp freeness, yield and handsheet density but the handsheet thickness was reduced.
Physics and anatomy
Majid Kiaei
Abstract
This study examined the effects of altitude and soil characteristics on wood properties of Eldar pine and soil characteristics in western of Mazandran forest. For this purpose, nine normal pine trees was selected from three classes of altitude 500, 1200, and 1400 m, which located in Chaloos region. Disks ...
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This study examined the effects of altitude and soil characteristics on wood properties of Eldar pine and soil characteristics in western of Mazandran forest. For this purpose, nine normal pine trees was selected from three classes of altitude 500, 1200, and 1400 m, which located in Chaloos region. Disks were cut at breast height for each of trees. Testing samples were taken in radial position from the pith to the bark to determine wood properties such as oven dry density, wood basic density, and annual ring width. For each of tress in three different altitudes, four soil profiles of 20-40cm depth was taken to examine soil physical and chemical properties include clay, silt, sand, pH, Mn, fe, cu, zn, P, and K. Then relationship between the soil and wood properties were investigated with Pearson correlation and multiple correlations. Results of soil and wood properties indicated that by increasing altitude, the amount of annual ring width was increased, and the wood density was decreased, while the clay, Mn, fe, and Cu content in altitude 1200m, silt, Zn and K in lower altitude and P and sand in higher altitude is higher than other altitudes. Among of above variables, only the effect of clay, sand, P and Fe of soils on the wood different properties by Pearson correlation. The relationship between soil and wood properties by forward stepwise regression indicated that
Physics and anatomy
Elahe Mehri; Ali Ghasemian
Abstract
The aim of this study was to investigate biometrical properties of bark, node and internode chemical components of Bamboo phyllostachys pubescens. The results showed, there were significant difference between fiber length of bark, node and internode; and internode had maximum fiber length and node had ...
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The aim of this study was to investigate biometrical properties of bark, node and internode chemical components of Bamboo phyllostachys pubescens. The results showed, there were significant difference between fiber length of bark, node and internode; and internode had maximum fiber length and node had minimum fiber length. There were also significant difference between lumen diameter and cell wall thickness; and node had the highest value. In terms of chemical compositions; amount of extractives, lignin and ash of node were more than internode, but there weren’t significant differences at the 95% confidence, while the amount of cellulose of internode was significantly more than node. Slenderness ratio, flexibility ratio and Raunkel ratio were also calculated for bark 93.06, 36.641, 172.916% and for node 46.308, 33.108, 202.035% and for internode 88.151, 31.678, 215.666% respectively. Generally the observations indicated that, according to the characteristics of the fiber of this nonwood plant, it can be recommended to produce pulp and paper.
Physics and anatomy
asghar tarmian
Abstract
In this study, some anatomical, chemical and physical properties of toothbrush wood (Salvadora persica L.) of Zabol region in Sistan and Baluchestan province were investigated. Anatomical studies showed that thi s species has short vessel with intermediate diameter, simple perforation plate and alternative ...
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In this study, some anatomical, chemical and physical properties of toothbrush wood (Salvadora persica L.) of Zabol region in Sistan and Baluchestan province were investigated. Anatomical studies showed that thi s species has short vessel with intermediate diameter, simple perforation plate and alternative intervessel pits. Ray parenchyma is homogeneous and of the procumbent cell type. Axial parenchyma is storied as seen in the tangential section and resembles paratracheal confluent arrangement in the cross section. Included phloem was present in xylem. The average fiber length, total diameter, lumen diameter and fiber wall thickening were 1898.5, 19.4, 8.2 and 5.6 µm, respectively. Chemical characteristics also showed that, toothbrush wood has average cellulose, lignin, extractives and ash content about 33.5, 21.5, 6.8 and 7.5%, respectively. The results also showed that the specific gravity of the wood was 0.49 and its mean tangential, radial and longitudinal shrinkages were 7.4, 7.8 and 0.98 %, respectively.
Physics and anatomy
Neda Sakhavati; Moslem Akbari nia; Hoshangh Zanganeh
Abstract
Cerasus mahaleb (L.) Mill is among the important broad-leaved trees in Zagros forests. Good bending property and the pleasant aroma helped the tree species to find a long history of rural and local uses. Wood consumption is closely influenced by the physical, biometric and other engineering properties. ...
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Cerasus mahaleb (L.) Mill is among the important broad-leaved trees in Zagros forests. Good bending property and the pleasant aroma helped the tree species to find a long history of rural and local uses. Wood consumption is closely influenced by the physical, biometric and other engineering properties. Three sound trees were harvested and tested according to ASTM-D143 standards testing procedures. Results showed that Cerasus mahaleb (L.) Mill has semi-heavy wood with high bending ability. Its compression strength parallel strain was measured as 48.45 MPa. The average fiber length and fiber diameter was 0.71 mm and 19.85 m respectively. Mean volume shrinkage and swelling was measured as 6.09% and 6.69% respectively. The radiant and tangent shrinkage and swelling after 2 and 24 hour immersion in water was 19.65%, 19.74%, 19.9%, 19.89%, 20.62% and 21.16% respectively. Mean annual diameter growth as well as mean height growth were 4.96 mm and 0.31 m respectively.
Physics and anatomy
Meisam Aliabadi; Eiman Akbarpoor; Ahmadreza Saraeyan; Jalil Roshnasan
Abstract
This research was performed to investigate fiber biometrical properties (length, diameter and fiber thickness) of hornbeam species from Astara in Iran. Initially, disks were prepared with three trees of hornbeam species and then fiber isolation was carried out using Franklin method. Length, diameter ...
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This research was performed to investigate fiber biometrical properties (length, diameter and fiber thickness) of hornbeam species from Astara in Iran. Initially, disks were prepared with three trees of hornbeam species and then fiber isolation was carried out using Franklin method. Length, diameter and wall thickness of fiber provided were determined by laboratory microscope using eye scaled lens. The measurement of fiber dimensions was made at the pith region and at the distances of 2,6,12 and 15 centimeters and four geographical sides. The results indicated that length, diameter and wall thickness of fiber increased significantly with enhance of distance from pith. The highest fiber length, diameter and wall thickness obtained were 1.509 mm, 23.93 µm and 3.897 µm, respectively. The consequences attained from changing of fiber dimensions at various distances from pith to bark indicated that fiber dimensions change decreased by increase in distance from pith up to 15 cm and the highest change of fiber was observed at distance of 2-6 cm from pith. The results of measuring the fiber dimensions at various geographical sides didn't indicate any significant deference between the values of fiber length, diameter and wall thickness at 1% level of probability. The combined effects of distance from pith and different geographical sides also did not show any significant deference on fiber dimensions.
Physics and anatomy
Mohammad reza Nicsresht sigharodi; Vahid reza Safdari; Mohammad javad Sepideh dam; sayed Khalil Hosseini hashemi
Abstract
Paper’s components identification is important for pulp and paper mills and many organizations. In the present study we tried to identify paper fibers and introduce the most important anatomical characteristics which are effective in identification. First anatomical characteristics of wood and ...
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Paper’s components identification is important for pulp and paper mills and many organizations. In the present study we tried to identify paper fibers and introduce the most important anatomical characteristics which are effective in identification. First anatomical characteristics of wood and non-wood species which are important in pulp and paper industry were investigated. Then the papers of 3 important paper mills in Iran (totally 5 different papers) which their raw material include forest species, imported pulp and waste paper were sampled and examined. Many slides have been prepared according to ISO 9184-1 (ISO 1990) standard and valuable Atlases useful for identification of exotic species were reviewed. At the end important anatomical characteristics were recorded. Results showed that the fiber identification of papers is feasible. For softwoods identification, cross-field pits and for hardwoods, vessel shape, including, spiral thickening, perforation plate, inter-vessel pits and especially ray- vessels pits are the most crucial features for identification. Parenchyma, fiber biometric properties and fiber shape, in most species were similar and least effective in identification process. Epidermal cells, parenchyma and vessels were the most important anatomical feature for identification of non-woods.
Physics and anatomy
Vahid reza Safdari; Meisam Golchinfar
Abstract
In this investigation, anatomical characteristics of Iranian native woods from Ulmaceaefamily: Ulmus glabra, Ulmus carpinifolia,Zelkova carpinifolia,Celtis australis have been compared. These 4 woods are similar and have been used in Iranian historical buildings and their identification would be important.Among ...
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In this investigation, anatomical characteristics of Iranian native woods from Ulmaceaefamily: Ulmus glabra, Ulmus carpinifolia,Zelkova carpinifolia,Celtis australis have been compared. These 4 woods are similar and have been used in Iranian historical buildings and their identification would be important.Among 4 species, Zelkova carpinifolia is somehow similar to Celtis australis while, Ulmus glabrar is close to Ulmus carpinifolia. Boundary cells of rays in Zelkova carpinifolia and Celtis australis are bigger than inside cells of rays. The difference between Zelkova carpinifolia and Celtis australis are in ray width. Ray width of Celtis australis is 7-8 cells, whereas Zelkova carpinifolia 5- 6 cells. The color of soluble (Glycerin + water)which have been used for softening of wood samples(2× 2 cm)for Zelkova carpinifolia got golden color but others grey. The difference between Ulmus glabra and Ulmus carpinifolia are in appearance of rays. The appearance of Ulmus carpinifolia’s ray is short and wide while ray of Ulmus glabrar is tall and slender. Meanwhile the frequency of rays in cross section of Ulmus carpinifolia is 6-8 per millimeter but in the case of Ulmus glabrar the figure is 4-5.
Physics and anatomy
Jalal Shakhes; Ahmad reza Saraeyan; Farhad Zynali
Abstract
This work investigated effect of height and cultivar on morphological properties of bast and core fiber of tobacco stalk (Nicotiana tabacum). Also, in this research cultivar effect on chemical properties of tobacco stalk were investigated. Selected cultivars include Barley and Virginia, and investigative ...
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This work investigated effect of height and cultivar on morphological properties of bast and core fiber of tobacco stalk (Nicotiana tabacum). Also, in this research cultivar effect on chemical properties of tobacco stalk were investigated. Selected cultivars include Barley and Virginia, and investigative height positions were chosen 5, 50 and 75% of stalk height. Results indicated that bast fiber length, diameter and wall thickness are more effective than those of core fiber. Chemical analysis of stalk’s parts indicated that cellulose and ash contents of bast were higher than those of core, but lignin content of bast was significantly less than that of core. Also, extractive material of bast was less. Statistic results showed that length and wall thickness of Barley’s bast fiber were higher compare to Virginia, but there was no significant difference in terms of morphological properties of core fibers between these cultivars. Cellulose percentage of Barley cultivar was higher, where as lignin, extractives and ash contents of Barley were lower than that of Virginia cultivar. Also, cultivar type didn’t have significant effect on contents of tobacco stalk parts (bast, core and pith). Results indicated that, fiber length, diameter and wall thickness of bast decreased as height increases, but in core fiber, just fiber length decreased and other properties of core fiber had different behavior. Moreover, bast and pith percentages increased by height increasing while, core percentage decreased. In general, results of this research showed that, tobacco stalk are a suitable row material for pulp and paper production, re fiber dimensions and chemical components.
Physics and anatomy
Maliheh Akhtari; Mehdi Arefkhani
Abstract
In this study acetylated Beech wood (Fagus orientalis Lipsky) has been subjected to a variety of artificial weathering conditions in different of times (0,150&300 h), then wood surface was analyzed for chemical changes using Fourier Transform Infrared (FTIR) spectroscopy and for structural changes ...
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In this study acetylated Beech wood (Fagus orientalis Lipsky) has been subjected to a variety of artificial weathering conditions in different of times (0,150&300 h), then wood surface was analyzed for chemical changes using Fourier Transform Infrared (FTIR) spectroscopy and for structural changes using Scanning Electron Microscopy (SEM) .Results showed that weathering process influence by the functional groups on the wood surface. Cycle of weathering (Light and water) caused the damage to the surface polymer structure and chemical and physical changes. The greatest changes caused by the functional groups and Aromatic structure of lignin. The SEM results showed that the surface of wood exposed to weathering undergoes distinct Physical changes. The surface degradation appears to be directly proportional to the time of exposure to the weathering conditions and acetylation of the wood to protect the surface from damages caused by the weathering effect of light and water.
Physics and anatomy
Kazem Dost hosseini; Hamideh Abdolzadeh
Abstract
The feasibility of using of wood and old corrugated container (OCC) fibers on the surface layers of particleboards was investigated. The kind of applied furnish at surface layers, the moisture and adhesive content were considered as variables and their effects on hardness and roughness of manufactured ...
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The feasibility of using of wood and old corrugated container (OCC) fibers on the surface layers of particleboards was investigated. The kind of applied furnish at surface layers, the moisture and adhesive content were considered as variables and their effects on hardness and roughness of manufactured particleboards were examined. The results indicated that the application of both wood fibers and OCC on the surface layers of particleboard resulted in improving surface quality. The moisture and adhesive contents at high levels led to improved surface quality. The control samples with 10% adhesive and 14% moisture content yielded more hardness than the other. The smoothest surfaces appeared on the particleboards manufactured with wood and OCC fibers as well as 14% moisture content and 12% adhesive.
Physics and anatomy
Jamail Visi; Ghanbar Ebrahimi; Mohssen Bahmani
Abstract
The aim of this study was investigating the parameters of mortise and tenon joint made out of beech and hornbeam and develop formula to estimate ultimate bending strength. Mortis and tenon joint, one of the joints type, in placed in both form of corner and cross. In furniture industry, Mortis and ...
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The aim of this study was investigating the parameters of mortise and tenon joint made out of beech and hornbeam and develop formula to estimate ultimate bending strength. Mortis and tenon joint, one of the joints type, in placed in both form of corner and cross. In furniture industry, Mortis and tenon joint is widely used, because of its low cost and easy utilization. In this study, the effects of tenon height 2.5 ,3.5 and 5 cm, shoulder width 0/125, 0/25 and 0/375 cm on the resistance of Mortis and tenon against the ultimate bending strength were investigated. The results showed that the highest ultimate bending strength of Mortis and tenon in hornbeam possessed to the 5 cm tenon height and 0/25 shoulder width. Finally, it was found that the ultimate bending strength () of the joint could be predicted by means of the formula , where ultimate bending strength , is shear strength of the wood, = rail rail, tenon height, shoulder width factor, adhesive factor, tenon fit factor
Physics and anatomy
Alireza Ghotibi far; Saeid Kazemi najafi; Rabi Behroz
Abstract
This research focused on the influence of content (5, 10 and 15 %) of glass fiber on the water absorption and thickness swelling of wood flour/E-glass fiber hybrid polypropylene composites without and with MAPP. The samples (strips with 10 mm thickness and 70 mm width) were made using a laboratory twin-screw ...
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This research focused on the influence of content (5, 10 and 15 %) of glass fiber on the water absorption and thickness swelling of wood flour/E-glass fiber hybrid polypropylene composites without and with MAPP. The samples (strips with 10 mm thickness and 70 mm width) were made using a laboratory twin-screw extruder. The water absorption and thickness swelling of the composites after 2h and 24h were determined. The results showed that adding glass fiber significantly increase water absorption and thickness swelling after 2h and 24h in absence of MAPP. Whereas in presence of 2% MAPP by addition glass fiber, no significant changes were observed in water absorption and thickness swelling of the composites after 2h and 24h. MAPP considerably decreased the water absorption and thickness swelling of the studied composites
Physics and anatomy
Ahmad Jahan - Latibari; Fardad Golbabaei; Amir Zyadzadeh; Majid Farzi; Arad Vaziryan
Abstract
Fiber length, diameter and lumen diameter and its distribution is determined. Five stalks were randomly selected and after cleaning, the internodes and nodes of each stalk were separated. Each part was depithed manually and then experimental samples were cut from these depithed parts. ...
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Fiber length, diameter and lumen diameter and its distribution is determined. Five stalks were randomly selected and after cleaning, the internodes and nodes of each stalk were separated. Each part was depithed manually and then experimental samples were cut from these depithed parts. Each sample was defibered according to procedure developed by Franklin, 1954. After defibration, fiber length, diameter and lumen diameter of 30 fibers were measured. Each stalk contained 10 nodes and internodes.
Average fiber length of internodes and nodes were determined at 1.004 and 0.802 millimeter respectively. The difference in averages of fiber length for different stalks, different heights in each stalk and between nodes and internodes were significant at 99% level. Fiber length distribution curves for internodes, nodes and all fibers show uniform and symmetrical distribution and the highest points in distribution curves are all at similar fiber length.
Average fiber diameter for internodes and nodes were determined at 16.8 and 20.1 µm respectively which are significantly different at 99% level. Fiber diameter distribution curves for nodes, internodes and all fibers also shows uniform and symmetrical shape, but the highest point for internodes is located at lower fiber diameter than nodes. The average lumen diameter for internodes and nodes were measured at 9.42 and 12.7 respectively which is significantly different at 99% level. The distribution curves for lumen diameter is identical to fiber diameter.
The results indicate that the fiber geometry of cornstalks is similar to hardwoods and other agricultural residues and it can be utilized for production of lower grade pulps such as fluting paper pulp.
Physics and anatomy
Davood Efhami; Ahmad reza Saraeyan
Abstract
In this study Populus alba native clone and Populus euramericana 476 clone trees from Gorgan University educative forest were used. Some applied anatomical and physical properties of these species were determined. Results showed that the juvenility age for both species is approximately 10 years .In both ...
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In this study Populus alba native clone and Populus euramericana 476 clone trees from Gorgan University educative forest were used. Some applied anatomical and physical properties of these species were determined. Results showed that the juvenility age for both species is approximately 10 years .In both species with increase of annual rings upto tenth ring the fiber length increase intensively. After tenth ring in P. alba this trend keep on slowly but in P. euramericana the average length of fiber decreased as increase of annual rings. With regard to the annual growth the juvenile wood percentage in the P. alba and euramericana species were 46.8% and 73.8%, respectively. Basic density of breast height in P. alba and P. euramericana species were 0.329 and 0.318 g/cm3 respectively, that increases from pith to bark. Furthermore there is significant difference between density of juvenile wood and mature wood in both species. The pattern of shrinkage in studied species had decreasing procedure from pith to bark.
Physics and anatomy
Fardad Golbabaei; Ghanbar Ebrahimi; Abolfazl Kargarfard; Abbas Fakhryan roghani
Abstract
Oak (Quercus castaneafolia C.A. Mey) is one of the most important broadleaf species in the Caspian Forests of Iran. The wood of oak is highly appreciated in domestic wood industries especially furniture industry.
In this study which is a part of the extensive surveying project of the main wood engineering ...
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Oak (Quercus castaneafolia C.A. Mey) is one of the most important broadleaf species in the Caspian Forests of Iran. The wood of oak is highly appreciated in domestic wood industries especially furniture industry.
In this study which is a part of the extensive surveying project of the main wood engineering properties of Iranian woods, the natural variations of strength and related properties of two trees of about 70 years old from Shafarod Forests in Gilan province were investigated.
The properties were determined from tests on small clear specimens in the green and dry conditions following the ASTM Standard. The mechanical and physical properties studied include: stress at elastic limits, modulus of rupture, modulus of elasticity and modulus of elasticity in static bending; shear parallel to grain, maximum crushing strength, fiber stress at proportional limit and modulus of elasticity in compression parallel to grain; compression perpendicular to grain and specific gravity.
The results of statistical analysis showed that the mechanical strength of the wood was found to be affected by percentage of moisture content of wood specimens, height of sample tree and to some extend by geographical; cal direction.
Physics and anatomy
Shamohammad Amiri; Ahmad Jahan latibari
Abstract
For the determined of Anatomical, Chemical and Physical characteristics of SAXAUL wood (Haloxylon persicum) from Haresabad-e-Sabzevar research station located in Khorasan-e- Razavi province 4 trees from this specie were selected and cut. Samples transferred to the Chemical laboratory in Alborz-e-Karaj ...
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For the determined of Anatomical, Chemical and Physical characteristics of SAXAUL wood (Haloxylon persicum) from Haresabad-e-Sabzevar research station located in Khorasan-e- Razavi province 4 trees from this specie were selected and cut. Samples transferred to the Chemical laboratory in Alborz-e-Karaj research center for studies. Anova-1 in mstat-c statistical software was used for statistical analysis. Anatomical characteristics measured Fiber length, Fiber diameter, lemun and cell wall thickness 336.22, 13.61, 3.68 and 4.99 micron, respectively. Paper making coefficients were also measured. Mix up coefficient; Flexibility coefficient and Rankle coefficient were 24.72, %27.05 and %2.71, respectively. Chemical characteristics measured cellulose, lignin, alcol-acetone soluble extractives, NaoH 1% soluble extractives, hot water soluble extractives and ash 46.50%, 29.54%, 7.37%, 16.25%, 6.92% and 1.27%, respectively. Physical characteristics measured of density, dry density and critical density 1024.25, 1003.83 and 913 gr. per cubic centimeter.
Physics and anatomy
Hossein Familian; Abdolrahman Hosseinzadeh; Mohammad hassan Asareh; Sayed mosa Sadeghi; Kamyar Salehi
Abstract
Ziziphus spina- christi of the family Rhamnaceae is widely distributed especially in the southern region of Iran and considered as one of the most drought - resistant sub species of the country. This investigation is the first attempt to study wood properties of this species, in order to contribute to ...
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Ziziphus spina- christi of the family Rhamnaceae is widely distributed especially in the southern region of Iran and considered as one of the most drought - resistant sub species of the country. This investigation is the first attempt to study wood properties of this species, in order to contribute to a better understanding of it. It seems necessary to recognize the best utilization of this wood that are potentially available and easy to caltivate in Iran.The results of this study revealed that Ziziphus spina - christi is a diffuse - porous with pores round to oval, dense, hard and fine - textured wood. The length of vessel elements is medium, and the diameter relative high, few vessels per unit area and the type of perforation plates is simple. Parenchyma scanty paratracheal, vasicentric and rarely aliform. Libriform fibers length medium, thin to thick - walled. Rays 1-2 cells wide with medium length and not visible with nakedeye, crystals are common in most rays. In this species also percentages of cellulose and lignin are high but ash and extractive soluble in acetone content was found to be low.