Research Paper
Jafar Ebrahimpour Kasmani; Mohammad Talaeipoor; Amir homan Hamasi; Ahmad Samariha
Abstract
The strength properties of paper produced from pulp obtained after 1, 2 and 4 weeks treatment of hornbeam chips with the Phanerochaete chrysosporium BKM - 1767 fungus was evaluated and compared with control samples. After preparing fungal specimens, hornbeam chips were exposed to this fungus for one ...
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The strength properties of paper produced from pulp obtained after 1, 2 and 4 weeks treatment of hornbeam chips with the Phanerochaete chrysosporium BKM - 1767 fungus was evaluated and compared with control samples. After preparing fungal specimens, hornbeam chips were exposed to this fungus for one of the three periods of 1, 2 and 4 weeks at 39oC temperature and 65% relative humidity. Then CMP pulp was prepared using treated chips, chemical treatment temperature of 165oC, for either 80 or 90 minutes and sodium sulfite charge of 14, 18 and 22% (based on oven dry weight of the wood). The liquor to chips was constant at 7 to 1. The results showed that the CMP pulping yield from treated chips was lower than control sample and the reduction after treatments for 1, 2 and 4 weeks was almost 1.64, 2.84, 6.20 percent respectively. Also the strength indices of paper such as tensile strength, burst strength, tear strength and folding endurance paper prepared from treated chips were lower than control chips
Research Paper
Sabah Ashrafi birghani; Ahmadreza Sraeyan
Abstract
The purpose of this study was to compare the effects of various concentrations of sodium hydroxide and treatment times on the properties of bagasse and Eastern cottonwood (Populus deltoids) cold soda pulp and paper. The cold soda pulp was prepared using various concentrations of sodium hydroxide (5, ...
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The purpose of this study was to compare the effects of various concentrations of sodium hydroxide and treatment times on the properties of bagasse and Eastern cottonwood (Populus deltoids) cold soda pulp and paper. The cold soda pulp was prepared using various concentrations of sodium hydroxide (5, 10, 15% based on oven dry weight), different treatment times (20, 40, 60 min.), and constant liquor to wood ratio of 10:1 at 25 ºC and atmospheric pressure. The pulp prepared after 40 min treatment time was selected and refined to the freeness of 400 ml CSF. Analysis of the properties of hand sheets was conducted based on completely randomized design. Duncan multiple range grouping test was used to classify the properties of papers. The results indicated that, the yield of pulp obtained from Eastern cottonwoodand bagasse pulp varied between 86.54% to 94.52% and 70.65 to 87.32% respectively. The absorbed alkali was varied from 2.15% to 4.78 % for Eastern cottonwood and 3.06% to 6.80% for bagasse. Eastern cottonwood had the highest yield, thickness and strength properties whereas the highest absorbed alkali and paper density were observed in bagasse. It was observed that as the concentration of sodium hydroxide was increased from 5% to 15%, the yield of pulp and the thickness of paper decreased, while the absorbed alkali, density and the strength properties of paper increased. In general, the cold soda pulp from Eastern cottonwood provided higher quality compared with bagasse under the same pulping conditions.
Research Paper
Composite wood products
Amir Nourbakhsh; Reza Hajihassani; Fardad Golbabaei; Moghgan Kohpayeh zadeh
Abstract
Wood fibers are increasingly being used as reinforcement in commercial thermoplastic composites due to their low cost, high specific strength properties and renewable nature. The ultimate goal of our research was to find the fundamental understanding of the mechanical behavior of poplar wood fiber/polypropylene ...
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Wood fibers are increasingly being used as reinforcement in commercial thermoplastic composites due to their low cost, high specific strength properties and renewable nature. The ultimate goal of our research was to find the fundamental understanding of the mechanical behavior of poplar wood fiber/polypropylene (PP) composites. The effect of wood fiber concentrations and compounding temperature on the mechanical properties of composites, prepared using MAPP as the coupling agent, was investigated. In the sample preparation, four levels of fiber loading (10, 20, 30, and 40 w/w%) and three compounding temperatures (180, 190, and 200oC) were used. The results revealed that the major changes in composite properties occurred at fiber contents above 30%. The results clearly showed that the fiber loading of 30 and 40 w/w% at 190oC provided adequate reinforcement to increase the tensile and flexural strength of the composite. The modulus also increased with increasing fiber content, because poplar wood fibers are believed to be more rigid than polymer. However, the addition of wood fibers resulted in the reduction of both elongation and impact strength properties of the composites. The FTIR spectroscopy showed that the polymer was bonded to the fibers by ester linkages and hydrogen bonds at 1705–1735 cm-1.
Research Paper
Reza Hajihassani; Hossein Hosseinkhani; Abolfazl Kargarfard; Fardad Golbabaei
Abstract
The impact of reeds residue addition on physical and mechanical properties of particleboard made from pomegranate pruning was investigated. Laboratory particleboard was made applying one of the three levels of press time (3, 4 and 5 minutes) and one of the four levels of reed ...
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The impact of reeds residue addition on physical and mechanical properties of particleboard made from pomegranate pruning was investigated. Laboratory particleboard was made applying one of the three levels of press time (3, 4 and 5 minutes) and one of the four levels of reed and pomegranate pruning mixture (1-100% reeds; 2- 75% reeds + 25% pomegranate pruning; 3- 50% reeds + 50% pomegranate pruning and 4- 25% reeds + 75% pomegranate pruning). Boards were made in three replicate and 36 boards were made. Boards were tested using relevant EN standard and results were analyzed based on complete randomized design (CRD) under factorial experiment. Results revealed that increasing of pomegranate pruning in the wood mixture imposed positive effect on MOR, MOE, IB and thickness swelling of the particleboard. The relevant values of MOR, and MOE of the boards produced using 25% reeds + 75% pomegranate pruning were determined as 16.20 MPa and 2533 MPa respectively. Also thickness swelling after for 2 and 24 hours soaking in water decreased from 17.51 and 33.21% to 9.33 and 16.84% respectively. Internal bond strength (IB) of boards made applying 3 minutes press time (0.17 MPa.) was higher than boards made pressed for either 4 or 5 minutes, which indicates that 3 minutes press time is the appropriate time to approach maximum MOR and minimum thickness swelling after 24 hours soaking in water.
Research Paper
Composite wood products
masoudreza habibi; Hossein Hosseinkhani; Saeed Mahdavi
Abstract
In this study, particleboard was produced using Mesquite (Prosopis juliflora) called Somr wood. Oven dry density of stem and branch wood was measured as 0.92, 0.72 g/cm3 whereas the bark weight percentage of stem and branch wood determined as 13.6 % and14 % respectively. The influence of raw material ...
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In this study, particleboard was produced using Mesquite (Prosopis juliflora) called Somr wood. Oven dry density of stem and branch wood was measured as 0.92, 0.72 g/cm3 whereas the bark weight percentage of stem and branch wood determined as 13.6 % and14 % respectively. The influence of raw material mixture (stem wood, branch wood, the blend of stem and branch wood, 50/50 w/w) and resin content 10% and 12 % (based on dry weight of the particle) on particleboard properties were investigated. Properties such as MOR, MOE, IB, thickness swelling after 2 and 24 hours immersion in water were determined according to EN standard. Except for MOE, the effect of raw material type on board properties was significant. Particleboards made from branch wood, had the highest MOR. Maximum IB was observed in boards made from the blend of stem and branch wood. With the exception of bending properties, the effect of resin content on all board properties was significant. Increasing the resin content improved board properties. The lowest value of thickness swelling after 2 and 24 hours immersion in water was obtained in particleboard made from stem wood
Research Paper
Shamsaldin Balapoor; Mahmood Kazemi
Abstract
Plants such as tree species respond to their surrounding environmental variations over their biological life cycle. One of the techniques to study the tree response to environmental conditions is dendrochronolog. In this study, 20 samples were prepared from 10 Zelkova carpinifolia trees in Badleh-Sari ...
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Plants such as tree species respond to their surrounding environmental variations over their biological life cycle. One of the techniques to study the tree response to environmental conditions is dendrochronolog. In this study, 20 samples were prepared from 10 Zelkova carpinifolia trees in Badleh-Sari area. The effects of climate variables (precipitation and temperature) on annual rings of Zelkova carpinifolia trees were examined. Samples rings cross-date was determined using dendrochronological method. Also a chronology of 78 years period was made (1932-2012 AD). Mean Sensitivity (MS), mean correlation coefficient between the samples (trees), EPS and SNR, were determined as 20%, 0.5, 0.88 and 4.11 respectively. Analysis of the relationship between growth and climate over the period of 1951 – 2005, using response function (RF) showed that temperature did not significantly affect growth but total precipitation in February had positive effect (r = 0.45 p <0.001) on the growth of Zelkova carpinifolia. Analysis of trees growth response to precipitation in February showed that precipitation in the periods 1976–1994 had significant impact on the growth. However, in recent years (2011-2006) the rate of effectiveness of the precipitation on tree growth was decreased. Finally it could be mentioned that Zelkova can be a useful tree species for dendroclimatological purposes in terms of high rate of MS, EPS and SNR.
Research Paper
Babak Mirzaei; Kazem Dosthosseini
Abstract
Lignocellulosic material used as raw material in pulp and paper production due to major chemical alterations produce different waste compounds and composite manufacturing is an area providing the opportunity to utilize such wastes. In order to investigate the feasibility of using papermaking sludge in ...
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Lignocellulosic material used as raw material in pulp and paper production due to major chemical alterations produce different waste compounds and composite manufacturing is an area providing the opportunity to utilize such wastes. In order to investigate the feasibility of using papermaking sludge in composite production, four combinations of wood flour/ papermaking sludge/ high density polyethylene ratio were formulated, then composite panels were made and the physical properties of manufactured panels were evaluated. The content of maleated polyethylene (MAPE) and the polymer was constant 2% and 38% respectively, for all formulations. The results indicated that long term water absorption in particular thickness swelling decreased with increasing sludge content. Furthermore, moisture diffusion coefficient of samples containing 30% sludge and 30% wood flour was more than others. The results revealed that using papermaking sludge can be an alternative option for lignocellulosic raw material.
Research Paper
Abolfazl Kargarfard
Abstract
The objective of this study was to determine the suitability of the wood produced by adaptable eucalypt species for MDF production. Eucalyptus steriaticalyx fibers were produced using different levels of steaming time (5 and 10 minutes), and then medium density fiberboards were produced using these fibers ...
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The objective of this study was to determine the suitability of the wood produced by adaptable eucalypt species for MDF production. Eucalyptus steriaticalyx fibers were produced using different levels of steaming time (5 and 10 minutes), and then medium density fiberboards were produced using these fibers and one of the two levels of press temperature (175 and 185 ºC) and one of the three levels of press time (3, 3.5 and 4 minutes). Physical and mechanical properties of the panels were measured and analyzed. The results indicated that increasing of steaming time, decreased board MOR. Also press temperature and press time had significant effect on MOR and MOE and as the press temperature and time increased, the MOR and MOE of the boards decreased. Furthermore, results indicated that by increasing steaming time, the thickness swelling of boards reduced. The press temperature had significant effect on thickness swelling of boards and increasing the press temperature reduced the thickness swelling. These results indicate that Eucalyptus steriaticalyx as a fast growing species with acceptable physical and mechanical properties is a suitable lignocellulosic raw material for the production of MDF.
Research Paper
Akbar Rostampoor haftkhani; Ghanbar Ebrahimi; Mohammad Arabi; Mehdi Tajvidi; Mohammad Layeghi
Abstract
The purpose of this study was to investigate the effects of the screw diameter and pilot holes diameter as well as end distance, thickness of side and main members and screw type on the lateral load of joints made from various screws on commercial wood-plastic composites. Three types of screws, including ...
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The purpose of this study was to investigate the effects of the screw diameter and pilot holes diameter as well as end distance, thickness of side and main members and screw type on the lateral load of joints made from various screws on commercial wood-plastic composites. Three types of screws, including sheet metal screws with gauges 8, 10, 14 (4, 5, 6 mm, nominally), wood screws with gauge 8 (4mm, nominally), and drywall screws with gauge 8 (4mm, nominally) were used. The results showed that lateral load of joints do not increase continuously with increase of screws diameter and this must be attributed to decrease of net section of joint members. However, with a given diameter of screw, lateral load of joint increased with the increase of end distance, thickness of joint members. Also, results showed that, with the increase of predrilled holes diameter up to root-diameter of screw, lateral load of joint decreased drastically. Concerning screw type effect, the lateral load of joint made using wood screw was higher than joints made with sheet metal and drywall screws.
Research Paper
Kamyar Salehi; Fardad Golbabaei; Saeed Mahdavi; Abas Fakhryan
Abstract
The characteristics of five common varieties of sugarcane cultivated in the southern Iran, including cp57-614, sp70-1143, cp69-106, cp48-103, and nco310 were evaluated. The characteristics measured were fiber dimension, papermaking coefficients, fiber yield, density and chemical component. cp69-106 revealed ...
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The characteristics of five common varieties of sugarcane cultivated in the southern Iran, including cp57-614, sp70-1143, cp69-106, cp48-103, and nco310 were evaluated. The characteristics measured were fiber dimension, papermaking coefficients, fiber yield, density and chemical component. cp69-106 revealed the longest fiber with the average length of 1.55 mm whereas cp57-614 had the shortest fiber with average length of 1.39 mm. The cp48-103 and cp69-106 were ranked as having the widest and narrowest fiber diameter as 25.38 and 20.42 micron respectively. The measurement of the density at 12% moisture content showed that sp70-1143 with 0.35g/cm-3 provide the highest value and the cp57-614 possessed the lowest density measured at 0.17g.cm-3. There existed statistically significant differences among other fiber characteristics and papermaking coefficients. In general, the result indicated that cp69-106 provides the optimal characteristics in comparison with the other varieties based on papermaking specifications.
Research Paper
Vahid reza ُSafdari; Behzad Shabani; Seyyed Khalil Hosseinihashemi; Mehran Roohnia; Vilma Bayamzadeh
Abstract
Air pollutantion in particular pollutants from automobile exhaust can affect anatomical and morphological characteristics of woods. In order to investigate the impact of this factor, Pinus eldarica trees of Chitgar park in Tehran, the area which is extended from south to crowded highway (polluted ...
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Air pollutantion in particular pollutants from automobile exhaust can affect anatomical and morphological characteristics of woods. In order to investigate the impact of this factor, Pinus eldarica trees of Chitgar park in Tehran, the area which is extended from south to crowded highway (polluted site) and in north to Alborz Mountain (unpolluted site) and the middle part (semi-polluted site) were sampled by increment borer. After cross-dating, the tree rings of recent 5 years were separated from the old rings. Then anatomical characteristics of cross section, including transition between early and latewood, tangential thickness of last formed latewood tracheides, frequency of ray and resin ducts and morphological characteristics of tracheids in three zones and in the same rings were studied. Results indicated that the ring width pattern of Pinus eldarica in three zones is somehow the same. The frequency of resin duct and rays and false rings in 2005 and 2006 in the polluted and semi-polluted site were higher compare to the unpolluted site. Fiber length, wall thickness (2d) and lumen size of trees of unpolluted site were more than the other two sites (Polluted and Semi-polluted). In general, it could be concluded that air pollution impact on tree ring width can reduce wood quality as well.
Research Paper
Pulp and paper
Saeideh Sharifi; Ahmad reza Saraeyan; Hossein Resalati
Abstract
Preparation and pre-treatment of raw material influences the pulp production time and color elimination. Pulp consistency during the treatment also influences the color reaction. In the preparation of the APMP pulp, bagasse was pretreated by either boiling water, 1% NaOH as well as 1% NaOH + 1% ...
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Preparation and pre-treatment of raw material influences the pulp production time and color elimination. Pulp consistency during the treatment also influences the color reaction. In the preparation of the APMP pulp, bagasse was pretreated by either boiling water, 1% NaOH as well as 1% NaOH + 1% H2O2. The liquor to bagasse ratio, treatment time and temperature of alkaline peroxide treatment were constant as 10:1, 30 min, and 70 °C respectively. The treatment duration was determined so that at least five percent of the initial hydrogen peroxide remained at the end of chemical treatment. Characteristics of hand sheets were determined according to the TAPPI standard. The results showed that, the duration of the treatment for pulp consistency of 10, 15 and 20% was 50, 30 and 10 minute, for sample pretreated with boiling water and 290, 230 and 170 minute for the sample pretreated with 1% NaOH + 1% H2O2. The highest brightness of the paper reached with bagasse pretreated in boiling water at 20 % consistency.
Research Paper
Pulp and paper
Amir hooman Hamasi; Mehdi Sabor; Mohammad Talaeipoor; Mohammad Azadfallah
Abstract
The aim of present study was to investigate the effects of xylanase enzyme obtained from Trichoderma viride on APMP pulp from Populus nigra wood. Treatment temperature, time, enzyme dosage and pulp consistency were varied. The results demonstrated that treating by xylanase has considerable effects on ...
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The aim of present study was to investigate the effects of xylanase enzyme obtained from Trichoderma viride on APMP pulp from Populus nigra wood. Treatment temperature, time, enzyme dosage and pulp consistency were varied. The results demonstrated that treating by xylanase has considerable effects on pulp. Paper brightness improved in average 2.5% ISO and the highest gain was 4.5%. Also, using enzyme resulted in enhancement of tear and burst indices. Breaking length of paper from enzyme treated pulp was increased to 4098 meters. Further treatment by xylanase reduced the pulp yield by 2.78% as compared to sample without enzyme treatment. The impact of other treatment such as washing by distilled water and alkaline extraction revealed that these treatments did not have significantly effect on the results of enzyme treatment. The optimum temperature, time, enzyme dosage and pulp consistency were 40-50° C, 70 minutes, 10 U/g of oven dried pulp and 10% respectively.
Research Paper
Mysam Abdolali sarbandi; Vahid Safdari; Sayed javad Sepidedam; Esmaeil Ganjyan
Abstract
In this research, the properties of cement fiberboard produced using different contents of nano-silica and bleached bagasse fibers were evaluated. Different ratios of bagasse fibers, cement and nano-silica were blended using an electrical blender. The mixture was then poured into a mould (15x18x18 ...
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In this research, the properties of cement fiberboard produced using different contents of nano-silica and bleached bagasse fibers were evaluated. Different ratios of bagasse fibers, cement and nano-silica were blended using an electrical blender. The mixture was then poured into a mould (15x18x18 cm dimension). The produced mould samples were matured for 14 days at room temperature and high moisture content (100%) and after maturing, the bending strength and physical properties of boards were measured. Results showed that both materials (naosilica and bagasse fibers) changed the bending and physical properties of the final boards. The bending strength of samples increased with the increase in nano-silica up to 1% and exceeding 1% decreased this property. It is because high content of silica (more than 1%) results in aggregate of nano-silica and cement and micro cracks occurred in samples. Also the increase in bagasse fiber up to 4% increased of bending strength of boards and more bagasse fibers decreased the bending strength. It is because high bagasse fibers cannot distribute in the cement matrix and fiber bundles reduced the bending strength. However, as the nano-silica and bagasse fibers content increase, the water and moisture absorption as well as thickness swelling increases, whereas density decreases.
Research Paper
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.
