Hamid Reza Taghiyari - Academia.edu (original) (raw)

Papers by Hamid Reza Taghiyari

International Biodeterioration & Biodegradation, 2014

This study looked at commercial particleboard treatment with 200 ppm nanosilver (NS) and nanocopp... more This study looked at commercial particleboard treatment with 200 ppm nanosilver (NS) and nanocopper (NC) suspensions (10e80 nm) to assess the effects on hardness and resistance to the white-rot fungus Trametes versicolor. Suspensions were added to mats at two levels (100 and 150 ml kg À1 dry weight wood particles) and comparison was made with control boards. Both metal nanoparticles had significantly improved resistance to T. versicolor, resulting in decreasing mass loss (ML). Nanocopper was more effective at lower levels. Fungal exposure was associated with reduced hardness in NS-control and NS100 treatments, whereas NS150 produced significant reduction in fungal growth. Copper more effectively protected panels from fungal attack. High significant correlation (85%) was found between ML and hardness values.

BioResources, 2014

Studies concerning the production of medium-density fiberboard (MDF) with kenaf as an alternative... more Studies concerning the production of medium-density fiberboard (MDF) with kenaf as an alternative fibrous material were carried out as an attempt to provide a sustainable and viable source for this lignocellulosic product. This work sought to evaluate the influence of fiber properties (including fiber length, width, wall thickness, and lumen diameter that affect aspect and flexibility ratios) on specific gas permeability in medium-density fiberboard (MDF) made from kenaf bast and core fibers, respectively. Results showed that MDF panels produced from kenaf core had significantly lower permeability than those produced from kenaf bast. This lower permeability was primarily related to the higher flexibility ratio of kenaf core fibers, which provided more surface connection area between fibers, resulting in higher integration among fibers. Lower ash and extractive contents of the core section also improved the efficiency of resin and the connection of fibers to each other; eventually lower permeability was observed in panels made from kenaf core. A high correlation was found between gas permeability and water absorption.

Holzforschung, 2014

The effects of exposing specimens of Oriental beech [ Fagus sylvatica subsp. orientalis (Lipsky) ... more The effects of exposing specimens of Oriental beech [ Fagus sylvatica subsp. orientalis (Lipsky) Greuter and Burdet] to the white-rot fungi Pleurotus ostreatus (Jacq.: Fr.) Kummer and Trametes versicolor (L.: Fr.) Pil á t strain 325 have been studied concerning the mechanical properties and chemical composition in terms of carbohydrates, cellulose, and lignin. Biological decay tests were carried out in accordance with the EN 113 standard specifications for 30 and 120 days. P. ostreatus had nearly the same deteriorating effects on the mechanical properties and chemical composition as that caused by T. versicolor . High and significant correlations were found between some mechanical properties with chemical components; for instance, the correlation coefficient (R 2 ) between impact bending and carbohydrate content was about 0.96. The changes of components influence the various mechanical properties to a different degree. Incipient fungal decay caused severe changes for impact bending and carbohydrate loss. Several other properties declined at 120-day exposure time, such as the hardness, compression strength parallel to grain, and cellulose and lignin losses.

Maderas. Ciencia y tecnología, 2013

International Biodeterioration & Biodegradation, 2014

and sharing with colleagues.

Special Topics & Reviews in Porous Media - An International Journal, 2013

BioResources, 2013

The effect of impregnation with wollastonite nanofibers, a nontoxic mineral material, on the biol... more The effect of impregnation with wollastonite nanofibers, a nontoxic mineral material, on the biological durability of poplar wood (Populus nigra) against a white-rot fungus (Trametes versicolor) was studied. Wollastonite nano-suspension with a concentration of 6.3% was used; the size range of the nano-wollastonite (NW) was 30 to 110 nm. Results showed that decay exposed for 16 weeks in accordance with the standard DIN-52176 specifications resulted in a 47.5% mass loss in control specimens, while in the NW-impregnated specimens, only 3.6% mass loss occurred. Mechanical tests on separate sets of specimens impregnated with NW without exposure to the decay organism showed no significant difference in the mechanical properties. Thus, it can be concluded that impregnating poplar wood with NW as a preservative significantly increases the biological durability of poplar wood against deterioration by Trametes versicolor. Furthermore, it does not have negative effects on the mechanical properties in the impregnated poplar specimens.

European Journal of Wood and Wood Products, 2013

Effects of a 200 ppm nanocopper suspension, with size range from 10 to 80 nm, on the physical and... more Effects of a 200 ppm nanocopper suspension, with size range from 10 to 80 nm, on the physical and mechanical properties of particleboard made on an industrial scale at the Iran-Choob Factory were studied. Nanocopper suspension was added to the mat at two levels of 100 and 150 ml/kg dry weight wood particles and compared with control boards. Results showed that hot-pressing time was reduced by 5.7 and 3.4 % when 100 and 150 ml of nanocopper were used, respectively. Also, both levels of nanocopper consumption had improving effects on physical and mechanical properties, although in some cases not significant. Permeability was significantly decreased to its lowest value in 150 ml/kg treatment. It can be concluded that 150 ml of nanocopper/kg may be used to improve the physical and mechanical properties, to reduce press time, and to decrease permeability in particleboards. For industrially accepted outcome, 150 ml/kg of nanocopper is recommended.

Maderas. Ciencia y tecnología, 2011

Heat-treatment, a major method of wood modification for improving dimensional stability and natur... more Heat-treatment, a major method of wood modification for improving dimensional stability and natural durability, has been studied considerably in the scientific literature. This study will focus on the effect of heat-treatment on permeability, an important physical property of wood by subjecting beech samples to two different mediums of hot water and steam, as well as in two buffered hot water of pH 7 and 8. Hydrothermal treatment caused gas permeability to decrease to its lowest value among the treatments (91.6% decrease comparing the control treatment). Hydrothermal treatment in buffered hot water of pH 8 made the lowest impact on gas permeability (12.3% decrease). The decrease in gas permeability was due to settlement of extractives on vessel perforation plates. Gas permeability showed a highly significant correlation with the amount of swelling in radial direction. Low correlation was found between liquid permeability with water absorption and the amount of swelling. Gas permeability is considered a suitable criterion for predicting the amount of swelling in beech wood.

Current Nanoscience, 2012

The present study is aimed at the effect of heat treatment on nanosilver-impregnated Populus nigr... more The present study is aimed at the effect of heat treatment on nanosilver-impregnated Populus nigra, Fagus orientalis, and Abies alba to find out nail and screw withdrawal resistance. Treatments included control, heat-treated, and nano-silver-impregnated heattreated specimens. Empty-cell process was used for impregnation with a 200 ppm aqueous dispersion of silver nanoparticles with the size range from 10 to 80 nm under 3 bars in a pressure vessel for 20 minutes. For heat treatment, both seasoned nano-silver-impregnated and heat-treatment specimens were kept for 24 hours at 135ºC. The nails and screws were installed according to ASTM D 1761-88 specifications. Results showed that the maximum nail and screw withdrawal resistance was closely related to the density. The difference between longitudinal and radial withdrawal resistance in both nail and screw was significantly influenced by the species as a softwood or hardwood. Regardless of the species, heat treatment was more influenced by the density rather than species. However, nano-silverimpregnation of the specimens aggravated the effects of heat treatment in hardwoods (more increasing in poplar and more decreasing in beech), but it decreased the withdrawal resistance in fir.

Materials & Design, 2013

The present study is aimed at determining the effects of nano-silver and nano-zycosil on biscuit ... more The present study is aimed at determining the effects of nano-silver and nano-zycosil on biscuit and dovetail MDF miter joints treated with heat, vapor chamber, and dry-ice-blasting. These two kinds of joints are very popular in cabinet-making industry and are used with or without adhesive on a large scale because of their strength as well as ease in making. Seven combinations of joints were made and treated with nanoparticles, including single and double dovetail with and without adhesive, and three sizes of biscuit joints. The size of the nanoparticles was between 20 and 80 nano-meter. Results showed that double-dovetail joint with adhesive had the best mechanical strength (3080 N). Heat and vapor-chamber treatments significantly decreased the strength of joints. Treatment with nanosilver generally decreased the strength of joints; the heat-transfer property of silver could not compensate for the loss in strength caused by heat treatment. Similarly, nano-zycosil significantly decreased the strength and its waterrepellant property did not result in improvement in the strength of specimens treated in vapor-chamber. Also, nano-silver is not recommended to be used for joints to be cleaned by ice-blasting, though the loading strength of nano-silver ice-blasted dovetail joints seemed to be slightly more than the control joints that were ice-blasted.

Maderas. Ciencia y tecnología, 2014

Effects of alfalfa-intercropping and nanosilver-impregnation were studied here on the specific ga... more Effects of alfalfa-intercropping and nanosilver-impregnation were studied here on the specific gas permeability of 10-year old Populus nigra var. betulifolia. Specimens were impregnated with a 200 ppm aqueous dispersion of silver nanoparticles under 250 kPa pressure; the results were then compared with the un-impregnated specimens. The size range of silver nanoparticles was 10 to 80 nm. After the initial measurement, specimens were kept in vaporized chamber for six months (43±2°C, and 80±3% relative humidity); permeability was measured every month. Results showed that maximum specific longitudinal gas permeability was observed in the nanosilver-impregnated inner-wood specimens of the treatment with alfalfa (1614,4 × 10 -13 m 3 m -1 ), and minimum permeability was found in the un-impregnated outer-wood specimens of the treatment without alfalfa (491,7 × 10 -13 m 3 m -1 ) before the vaporization. Vaporized chamber made permeability decrease permeability at the first phases because of the absorption of water vapors and the consequent swelling; however, due to the proliferation of pits and perforation plates by fungi and molds, permeability was eventually increased. Antibacterial property of silver did not significantly decrease the growth of molds and fungi in the nanosilver-impregnated specimens. Maderas. Ciencia y tecnología 16(1): 49-62, 2014 Universidad del Bío -Bío Taghiyari, H.R.; Farajpour B, O. 2013. Effect of copper nanoparticles on permeability, physical, and mechanical properties of particleboard. European Journal of Wood Products 71(1): 69-77. Taghiyari, H.R.; Mobini, K.; Sarvari Samadi, Y.; Doosti, Z.; Karimi, F.; Asghari, M.; Jahangiri, A.; Nouri, P. 2013. Effects of nano-wollastonite on thermal conductivity coefficient of medium-density fiberboard. Journal of Nanomaterials and Molecular Nanotechnology 2:1. Woo, K.L.; Watson, P.; Mansfield, S.D. 2005. The Effects of Mountain Pine Beetle Attack on Lodgepole Pine Wood Morphology and Chemistry: Implications for Wood and Fiber Quality. Wood and Fiber Science 37(1): 112-126. Yu, Y.; Jiang, Z.; Wang, G.; Tian, G.; Wang, H.; Song, Y. 2012. Surface functionalization of bamboo with nanostructured ZnO. Wood Science and Technology 46(4):781-790. Zobel, B. 1992. Silvicultural effect on wood properties. IPEF International, Piracicaba (2): 31-38.

Heat and Mass Transfer, 2014

Effects of heat-treatment on longitudinal permeability of circular and square wood specimens were... more Effects of heat-treatment on longitudinal permeability of circular and square wood specimens were studied here. Specimens were heated to 50, 75, 100, 125, 150, and 185°C. Results showed that permeability increased at the lowest temperature due to shrinkage; then, it decreased due to irreversible hydrogen bonding and stiffness. The highest temperature increased permeability due to micro-cracks. The higher perimeter in the square specimens aggravated the effects of heat treatment.

European Journal of Wood and Wood Products, 2013

ABSTRACT Effects of wollastonite nanofibers on fire-retarding properties of medium density fiberb... more ABSTRACT Effects of wollastonite nanofibers on fire-retarding properties of medium density fiberboard were studied. Nanowollastonite (NW) was applied at 5, 10, 15, and 20 g/kg dry weight basis of wood fibers and compared with reference specimens. Two application methods of NW were used: surface application (SA), and internal application. Density was kept constant at 670 kg/m3 for all treatments. Specimens of 150 × 130 × 9 mm³ were prepared and fire-retarding properties were measured using two devices: slide fire test device and fixed fire test device. The properties included: weight loss, ignition and glowing times, width and length of the burnt area, and fire endurance. The obtained results indicated that most fire-retarding properties were significantly improved with the increase in NW-content up-to 15 %, including weight loss, ignition and glowing times, and fire endurance. Higher amounts resulted in decreasing of the properties which was partly due to the less fiber-content, and partly due to the absorption of resin by the wollastonite nanofibers. It can be concluded that SA of NW is more effective in improving fire-retarding properties of medium density fiberboard. Furthermore, 10 % of NW is recommended as an optimum level of consumption.

European Journal of Wood and Wood Products, 2014

and sharing with colleagues.

Special Topics & Reviews in Porous Media - An International Journal, 2010

Journal of Nanomaterials & Molecular Nanotechnology, 2013

Wood Science and Technology, 2013

ABSTRACT

Special Topics & Reviews in Porous Media - An International Journal, 2010

International Biodeterioration & Biodegradation, 2014

This study looked at commercial particleboard treatment with 200 ppm nanosilver (NS) and nanocopp... more This study looked at commercial particleboard treatment with 200 ppm nanosilver (NS) and nanocopper (NC) suspensions (10e80 nm) to assess the effects on hardness and resistance to the white-rot fungus Trametes versicolor. Suspensions were added to mats at two levels (100 and 150 ml kg À1 dry weight wood particles) and comparison was made with control boards. Both metal nanoparticles had significantly improved resistance to T. versicolor, resulting in decreasing mass loss (ML). Nanocopper was more effective at lower levels. Fungal exposure was associated with reduced hardness in NS-control and NS100 treatments, whereas NS150 produced significant reduction in fungal growth. Copper more effectively protected panels from fungal attack. High significant correlation (85%) was found between ML and hardness values.

BioResources, 2014

Studies concerning the production of medium-density fiberboard (MDF) with kenaf as an alternative... more Studies concerning the production of medium-density fiberboard (MDF) with kenaf as an alternative fibrous material were carried out as an attempt to provide a sustainable and viable source for this lignocellulosic product. This work sought to evaluate the influence of fiber properties (including fiber length, width, wall thickness, and lumen diameter that affect aspect and flexibility ratios) on specific gas permeability in medium-density fiberboard (MDF) made from kenaf bast and core fibers, respectively. Results showed that MDF panels produced from kenaf core had significantly lower permeability than those produced from kenaf bast. This lower permeability was primarily related to the higher flexibility ratio of kenaf core fibers, which provided more surface connection area between fibers, resulting in higher integration among fibers. Lower ash and extractive contents of the core section also improved the efficiency of resin and the connection of fibers to each other; eventually lower permeability was observed in panels made from kenaf core. A high correlation was found between gas permeability and water absorption.

Holzforschung, 2014

The effects of exposing specimens of Oriental beech [ Fagus sylvatica subsp. orientalis (Lipsky) ... more The effects of exposing specimens of Oriental beech [ Fagus sylvatica subsp. orientalis (Lipsky) Greuter and Burdet] to the white-rot fungi Pleurotus ostreatus (Jacq.: Fr.) Kummer and Trametes versicolor (L.: Fr.) Pil á t strain 325 have been studied concerning the mechanical properties and chemical composition in terms of carbohydrates, cellulose, and lignin. Biological decay tests were carried out in accordance with the EN 113 standard specifications for 30 and 120 days. P. ostreatus had nearly the same deteriorating effects on the mechanical properties and chemical composition as that caused by T. versicolor . High and significant correlations were found between some mechanical properties with chemical components; for instance, the correlation coefficient (R 2 ) between impact bending and carbohydrate content was about 0.96. The changes of components influence the various mechanical properties to a different degree. Incipient fungal decay caused severe changes for impact bending and carbohydrate loss. Several other properties declined at 120-day exposure time, such as the hardness, compression strength parallel to grain, and cellulose and lignin losses.

Maderas. Ciencia y tecnología, 2013

International Biodeterioration & Biodegradation, 2014

and sharing with colleagues.

Special Topics & Reviews in Porous Media - An International Journal, 2013

BioResources, 2013

The effect of impregnation with wollastonite nanofibers, a nontoxic mineral material, on the biol... more The effect of impregnation with wollastonite nanofibers, a nontoxic mineral material, on the biological durability of poplar wood (Populus nigra) against a white-rot fungus (Trametes versicolor) was studied. Wollastonite nano-suspension with a concentration of 6.3% was used; the size range of the nano-wollastonite (NW) was 30 to 110 nm. Results showed that decay exposed for 16 weeks in accordance with the standard DIN-52176 specifications resulted in a 47.5% mass loss in control specimens, while in the NW-impregnated specimens, only 3.6% mass loss occurred. Mechanical tests on separate sets of specimens impregnated with NW without exposure to the decay organism showed no significant difference in the mechanical properties. Thus, it can be concluded that impregnating poplar wood with NW as a preservative significantly increases the biological durability of poplar wood against deterioration by Trametes versicolor. Furthermore, it does not have negative effects on the mechanical properties in the impregnated poplar specimens.

European Journal of Wood and Wood Products, 2013

Effects of a 200 ppm nanocopper suspension, with size range from 10 to 80 nm, on the physical and... more Effects of a 200 ppm nanocopper suspension, with size range from 10 to 80 nm, on the physical and mechanical properties of particleboard made on an industrial scale at the Iran-Choob Factory were studied. Nanocopper suspension was added to the mat at two levels of 100 and 150 ml/kg dry weight wood particles and compared with control boards. Results showed that hot-pressing time was reduced by 5.7 and 3.4 % when 100 and 150 ml of nanocopper were used, respectively. Also, both levels of nanocopper consumption had improving effects on physical and mechanical properties, although in some cases not significant. Permeability was significantly decreased to its lowest value in 150 ml/kg treatment. It can be concluded that 150 ml of nanocopper/kg may be used to improve the physical and mechanical properties, to reduce press time, and to decrease permeability in particleboards. For industrially accepted outcome, 150 ml/kg of nanocopper is recommended.

Maderas. Ciencia y tecnología, 2011

Heat-treatment, a major method of wood modification for improving dimensional stability and natur... more Heat-treatment, a major method of wood modification for improving dimensional stability and natural durability, has been studied considerably in the scientific literature. This study will focus on the effect of heat-treatment on permeability, an important physical property of wood by subjecting beech samples to two different mediums of hot water and steam, as well as in two buffered hot water of pH 7 and 8. Hydrothermal treatment caused gas permeability to decrease to its lowest value among the treatments (91.6% decrease comparing the control treatment). Hydrothermal treatment in buffered hot water of pH 8 made the lowest impact on gas permeability (12.3% decrease). The decrease in gas permeability was due to settlement of extractives on vessel perforation plates. Gas permeability showed a highly significant correlation with the amount of swelling in radial direction. Low correlation was found between liquid permeability with water absorption and the amount of swelling. Gas permeability is considered a suitable criterion for predicting the amount of swelling in beech wood.

Current Nanoscience, 2012

The present study is aimed at the effect of heat treatment on nanosilver-impregnated Populus nigr... more The present study is aimed at the effect of heat treatment on nanosilver-impregnated Populus nigra, Fagus orientalis, and Abies alba to find out nail and screw withdrawal resistance. Treatments included control, heat-treated, and nano-silver-impregnated heattreated specimens. Empty-cell process was used for impregnation with a 200 ppm aqueous dispersion of silver nanoparticles with the size range from 10 to 80 nm under 3 bars in a pressure vessel for 20 minutes. For heat treatment, both seasoned nano-silver-impregnated and heat-treatment specimens were kept for 24 hours at 135ºC. The nails and screws were installed according to ASTM D 1761-88 specifications. Results showed that the maximum nail and screw withdrawal resistance was closely related to the density. The difference between longitudinal and radial withdrawal resistance in both nail and screw was significantly influenced by the species as a softwood or hardwood. Regardless of the species, heat treatment was more influenced by the density rather than species. However, nano-silverimpregnation of the specimens aggravated the effects of heat treatment in hardwoods (more increasing in poplar and more decreasing in beech), but it decreased the withdrawal resistance in fir.

Materials & Design, 2013

The present study is aimed at determining the effects of nano-silver and nano-zycosil on biscuit ... more The present study is aimed at determining the effects of nano-silver and nano-zycosil on biscuit and dovetail MDF miter joints treated with heat, vapor chamber, and dry-ice-blasting. These two kinds of joints are very popular in cabinet-making industry and are used with or without adhesive on a large scale because of their strength as well as ease in making. Seven combinations of joints were made and treated with nanoparticles, including single and double dovetail with and without adhesive, and three sizes of biscuit joints. The size of the nanoparticles was between 20 and 80 nano-meter. Results showed that double-dovetail joint with adhesive had the best mechanical strength (3080 N). Heat and vapor-chamber treatments significantly decreased the strength of joints. Treatment with nanosilver generally decreased the strength of joints; the heat-transfer property of silver could not compensate for the loss in strength caused by heat treatment. Similarly, nano-zycosil significantly decreased the strength and its waterrepellant property did not result in improvement in the strength of specimens treated in vapor-chamber. Also, nano-silver is not recommended to be used for joints to be cleaned by ice-blasting, though the loading strength of nano-silver ice-blasted dovetail joints seemed to be slightly more than the control joints that were ice-blasted.

Maderas. Ciencia y tecnología, 2014

Effects of alfalfa-intercropping and nanosilver-impregnation were studied here on the specific ga... more Effects of alfalfa-intercropping and nanosilver-impregnation were studied here on the specific gas permeability of 10-year old Populus nigra var. betulifolia. Specimens were impregnated with a 200 ppm aqueous dispersion of silver nanoparticles under 250 kPa pressure; the results were then compared with the un-impregnated specimens. The size range of silver nanoparticles was 10 to 80 nm. After the initial measurement, specimens were kept in vaporized chamber for six months (43±2°C, and 80±3% relative humidity); permeability was measured every month. Results showed that maximum specific longitudinal gas permeability was observed in the nanosilver-impregnated inner-wood specimens of the treatment with alfalfa (1614,4 × 10 -13 m 3 m -1 ), and minimum permeability was found in the un-impregnated outer-wood specimens of the treatment without alfalfa (491,7 × 10 -13 m 3 m -1 ) before the vaporization. Vaporized chamber made permeability decrease permeability at the first phases because of the absorption of water vapors and the consequent swelling; however, due to the proliferation of pits and perforation plates by fungi and molds, permeability was eventually increased. Antibacterial property of silver did not significantly decrease the growth of molds and fungi in the nanosilver-impregnated specimens. Maderas. Ciencia y tecnología 16(1): 49-62, 2014 Universidad del Bío -Bío Taghiyari, H.R.; Farajpour B, O. 2013. Effect of copper nanoparticles on permeability, physical, and mechanical properties of particleboard. European Journal of Wood Products 71(1): 69-77. Taghiyari, H.R.; Mobini, K.; Sarvari Samadi, Y.; Doosti, Z.; Karimi, F.; Asghari, M.; Jahangiri, A.; Nouri, P. 2013. Effects of nano-wollastonite on thermal conductivity coefficient of medium-density fiberboard. Journal of Nanomaterials and Molecular Nanotechnology 2:1. Woo, K.L.; Watson, P.; Mansfield, S.D. 2005. The Effects of Mountain Pine Beetle Attack on Lodgepole Pine Wood Morphology and Chemistry: Implications for Wood and Fiber Quality. Wood and Fiber Science 37(1): 112-126. Yu, Y.; Jiang, Z.; Wang, G.; Tian, G.; Wang, H.; Song, Y. 2012. Surface functionalization of bamboo with nanostructured ZnO. Wood Science and Technology 46(4):781-790. Zobel, B. 1992. Silvicultural effect on wood properties. IPEF International, Piracicaba (2): 31-38.

Heat and Mass Transfer, 2014

Effects of heat-treatment on longitudinal permeability of circular and square wood specimens were... more Effects of heat-treatment on longitudinal permeability of circular and square wood specimens were studied here. Specimens were heated to 50, 75, 100, 125, 150, and 185°C. Results showed that permeability increased at the lowest temperature due to shrinkage; then, it decreased due to irreversible hydrogen bonding and stiffness. The highest temperature increased permeability due to micro-cracks. The higher perimeter in the square specimens aggravated the effects of heat treatment.

European Journal of Wood and Wood Products, 2013

ABSTRACT Effects of wollastonite nanofibers on fire-retarding properties of medium density fiberb... more ABSTRACT Effects of wollastonite nanofibers on fire-retarding properties of medium density fiberboard were studied. Nanowollastonite (NW) was applied at 5, 10, 15, and 20 g/kg dry weight basis of wood fibers and compared with reference specimens. Two application methods of NW were used: surface application (SA), and internal application. Density was kept constant at 670 kg/m3 for all treatments. Specimens of 150 × 130 × 9 mm³ were prepared and fire-retarding properties were measured using two devices: slide fire test device and fixed fire test device. The properties included: weight loss, ignition and glowing times, width and length of the burnt area, and fire endurance. The obtained results indicated that most fire-retarding properties were significantly improved with the increase in NW-content up-to 15 %, including weight loss, ignition and glowing times, and fire endurance. Higher amounts resulted in decreasing of the properties which was partly due to the less fiber-content, and partly due to the absorption of resin by the wollastonite nanofibers. It can be concluded that SA of NW is more effective in improving fire-retarding properties of medium density fiberboard. Furthermore, 10 % of NW is recommended as an optimum level of consumption.

European Journal of Wood and Wood Products, 2014

and sharing with colleagues.

Special Topics & Reviews in Porous Media - An International Journal, 2010

Journal of Nanomaterials & Molecular Nanotechnology, 2013

Wood Science and Technology, 2013

ABSTRACT

Special Topics & Reviews in Porous Media - An International Journal, 2010

The present study is focused on the effects of the shape and size of Fagus orientalis wood flour ... more The present study is focused on the effects of the shape and size of Fagus orientalis wood flour on physical and mechanical properties of HDPE based wood plastic composites (WPC). Variables included two mesh sizes (20 and 60), as well as five different contents of ground shavings (0, 25, 50, 75, and 100%) mixed with sawdust; totally 10 treatments. HDPT content was 40% in all formulations. Panels were compression molded and physical and mechanical tests were carried out in accordance with ASTM D2240 standard specifications. Results showed that mesh size can only significantly affect the hardness in the studied wood-plastic composites. On the other hand, increasing the proportion of the ground shavings possessing higher aspect ratio (l/d) increased both flexural strength and hardness. This increasing effect however was not observed for ground shavings beyond 50%. It was also concluded that while the addition of ground shavings up to 50% could improve the mechanical properties, higher proportions would reduce some of the properties, particularly the impact strength. In was concluded that the panel made of 50% wood flour combined with 50% ground shavings exhibited overall suitable properties for most applications.