Composite wood products
Abolfazl Kargarfard; Amir Nourbakhsh; Fardad Golbabaei
Abstract
The objective of this study was to investigate of possibility of MDF production from successful Eucalyptus Species. Eucalyptus camaldulensis fibers were produced using different levels of steaming time ( 7.5 and 15 minutes), press temprature (170, 180 and 190 ºC ) and press time (3 and ...
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The objective of this study was to investigate of possibility of MDF production from successful Eucalyptus Species. Eucalyptus camaldulensis fibers were produced using different levels of steaming time ( 7.5 and 15 minutes), press temprature (170, 180 and 190 ºC ) and press time (3 and 4 minutes) and used for panel making. Physical and mechanical properties of panels were measured and analyzed. The results indicated that increasing of steaming time, lowered MOR of boards. The press temprature had significant effect on MOR, and with increasing press temprature, MOR increased. Furthermore increasing of steaming time, decreased the IB of boards and increasing steaming time from 7.5 to 15 minutes, decreased IB from 0.787 to 0.533 MPa. Increasing of steaming time, also decreased thickness swelling of boards. However, the results of this study showed that, the MOR and MOE of boards produced from Eucalyptus camaldulensis fibers are around standard level. But in other hand, the internal bonding and thickness swelling of boards are higher than level standard.
Pulp and paper
Behzad Kord
Abstract
This study is for identifying of the effect of refining intensity on pulp and paper properties made from eucalyptuswood. For this purpose three normal eucalyptus camaldulensis spp trees were randomly cut down from Shastkolateh Experimental Forest located in Gorgan. From each tree, one disk ...
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This study is for identifying of the effect of refining intensity on pulp and paper properties made from eucalyptuswood. For this purpose three normal eucalyptus camaldulensis spp trees were randomly cut down from Shastkolateh Experimental Forest located in Gorgan. From each tree, one disk with 50cm thickness from breast height were selected for pulp making. Then disks converted to chips by chipper, and the chips were cooked by kraft process, the cooking conditions were as following effective alkali 20%, sulfidity 25%, tempreture 190 0C and Time 90min. After cooking and pulping process, the pulp refined with PFI Mill in 5 different intensity with 0 rpm, 500 rpm, 1500 rpm, 2500 rpm and 3500 revelutions. Then, papermaking and measuring the paper properties such as freeness, tensile strength, tear strength, burst strength and density were done. Then data were statisticaly analysed. The results indicated that, there are significant difference between pulp and paper properties made of eucalyptus camaldulensis spp wood with 5 different refining intensity in 95% confident level. As increasing of refining intensity and refining revolutions, freeness and tear strength of paper decreased but tensile strength, burst strength and density of paper incrased. However, the highest value of freeness and tear strength of paper related to refining intensity with 0rpm revelution (without refining) and highest value of tensile strength, burst strength and density of paper related to refining intensity with 3500rpm revelution
Saeideh Sharifi; Jalil Roshanasan; Sayed zya aldin Hosseini
Abstract
Okaliptus is a fast –growing and light – liking tree that its trunk is smooth and is shelled spontaneously. n a short time its diameter and height increase.for its fast growing. So that turing it into things is difficult Fiber s traction is high and deksity is 0.55 to 0.58 a square centimeter. ...
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Okaliptus is a fast –growing and light – liking tree that its trunk is smooth and is shelled spontaneously. n a short time its diameter and height increase.for its fast growing. So that turing it into things is difficult Fiber s traction is high and deksity is 0.55 to 0.58 a square centimeter. The samples were prepared from the branches and trunk of Ocalyptus Kameldolensis with the average old of three years, from Jiroft region in Kerman province. After ordaining the age and having samples from the same age , some discs were prepared for cutting to measure fibers.Making ready and suspension of fibers were done in Fraklin method .Measuring amaout of lignin was done to standard no: T222- om – 88 and TAPPI guide directions . Measuring cellulose was done according to Nitric Acid method and due to standard No : T264 – om – 88 , and TAPPI guide directions. Due to results the length of trunk fibers was 811.36 and branches was 845.68 micro meters.Diameter of trunk fibers is 19.3 but branches 15.64, these amounts don,t have a meaningful differnce the level of 5&1 percent . Diameter of the carity of rrunk fibers was 10.71, but branches 3.44 at the level of 5&1 percent , they don,t have a meaningful difference. The amount of extracted articles of trunk is 4/5 but branches 2.3 percent ,and amount of lignin in trunk was 35.66 but in the branch 24.66, and amount of cellulose in trunk was 55.66 and the branch 46.81 percent which at the level of 5&1 percent have a meaningful difference . The amount of Ashes from trunk was 0.73 but from the branch 0.88 that at the level of 5&1 percent , don,t have a meaningful defference.
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.
Physics and anatomy
Abdolrahman Hosseinzadeh; Abbas Fakhryan roghani; Fardad Golbabaei; Nayeralsadat Sadraei
Abstract
Eight-nineteen-year-old trees from Eucalyptus camaldulensis from De- hnow experimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. Form each tree, 10 cm. thick cross-sectional discs at several different heights (3 meters intervals) ...
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Eight-nineteen-year-old trees from Eucalyptus camaldulensis from De- hnow experimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. Form each tree, 10 cm. thick cross-sectional discs at several different heights (3 meters intervals) were cut and together with remaining boles then transferred 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 methods for air-dry and green conditions. The following conclusions were drawn from this study:E. camaldulensis from one site in southern region of Iran has an average specific gravity of 0.806, Fiber length of 1.043 mm, fiber diameter of 15.38 mm, lumen diameter of 4.84 mm, cell wall thickness 5.29 mm, cellulose content of 42.5 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 81.19 MPa, 10887 MPa and 67.39 MPa respectively.Data are also presented on other mechanical properties such as impact strength, nail withdrawal cleavage and etc.