This study deals with the effect of heat treatment on Pinus oocarpa specimens from forest plantat... more This study deals with the effect of heat treatment on Pinus oocarpa specimens from forest plantations in Colombia. The effects of two heat treatments at 170 and 190 °C for 2.5 h in saturated vapor were evaluated based on the color, dimensional stability, air-dry and basic densities, modulus of elasticity (MOE), and modulus of rupture (MOR) in static bending of samples. The evaluations were carried out following the Colombian Technical Standards NTC 290 and 663, and the color changes resulting from heat treatments were monitored using the CIE-Lab, as well as other standards from the literature. The results show that there was 2.4% and 3.3% mass loss of wood modified at 170 and 190 °C, respectively. The air-dry and basic densities were higher in 170 °C treatment than after 190 °C treatment, and the thermal modifications applied increased the dimensional stability of the treated wood. After treatment at 170 and 190 °C, the lightness to darkness (L*) was reduced by 10% and 22%; the a* c...
This paper studies the relationship between apparent density and some anatomical properties of Eu... more This paper studies the relationship between apparent density and some anatomical properties of Eucalyptus nitens such as vessel frequency, vessel area, ring width, fiber cell wall thicknesses, and fiber length. The study involved 29 trees from 10 families of Eucalyptus nitens cut from a 17-yr-old plantation in Southern Chile. The properties were determined along the radial direction of the trees by using X-ray equipment and at selected positions through microscope and fiber quality analyzer equipment. The results showed that the anatomical properties of E. nitens did not change gradually from pith to bark, but they were better described by dividing the tree radius into three different wood-zones referred as inner-, middle-, and outer-wood. The apparent density of E. nitens was dependent of the vessel area, cell wall area, ring width, and latewood width. The correlation coefficient between apparent density and vessels area was negative and the correlation coefficient between apparent...
This paper studies the relationship between apparent density and some anatomical properties of Eu... more This paper studies the relationship between apparent density and some anatomical properties of Eucalyptus nitens such as vessel frequency, vessel area, ring width, fiber cell wall thicknesses, and fiber length. The study involved 29 trees from 10 families of Eucalyptus nitens cut from a 17-yr-old plantation in Southern Chile. The properties were determined along the radial direction of the trees by using X-ray equipment and at selected positions through microscope and fiber quality analyzer equipment. The results showed that the anatomical properties of E. nitens did not change gradually from pith to bark, but they were better described by dividing the tree radius into three different wood-zones referred as
In order to evaluate evolution of physical and mechanical properties due to drying and heat modif... more In order to evaluate evolution of physical and mechanical properties due to drying and heat modification, a load of radiata pine wood was selected and properties were measured after each drying process. The results revealed interesting correlations between intrinsic factors and properties; the values of density were highly dispersed after drying or thermal treatment and uncorrelated with others parameters, but the minimum density values were kept constant after heat-treatment. Moreover, weight loss (WL) and moisture content (MC) were decreasing proportionally to the treatment intensity, due to wood-water interactions, cell wall changes and thermal degradation of wood fractions. WL and MC were reasonably correlated with the dimensional stability, improving the dimensional stability after drying treatments but keeping the same order of anisotropy. Regarding the wood stiffness (MOE), it was unaffected by the drying temperature, and the correlations between MOE and MC or WL appear to be acceptable, and the values of MC or WL did not adversely affect the MOE. However, the modulus of rupture was dropped during the drying process, obtaining three differentiated groups with a decrease of around 59% after thermal modification
The Effect of Wood Drying and Heat Modification on Some Physical and Mechanical Properties of Radiata Pine.
Wood and Fiber Science Journal of the Society of Wood Science and Technology, Dec 4, 2012
ABSTRACT This is a summary of a study carried out in Chile to certify industrial kiln drying of r... more ABSTRACT This is a summary of a study carried out in Chile to certify industrial kiln drying of radiata pine to comply with the international phytosanitary standard ISPM 15. The drying tests were performed in 100-m3 industrial kilns located at four different sawmills of the VIII region in Chile. The objective was to develop a standard protocol to certify industrial drying of radiata pine depending on the drying schedule and wood thickness. In part, the results were used to develop a multiple regression equation that permits sawmills to select their drying schedules in such a way that the lumber can be officially stamped as both kiln-dried and heat-treated for international trade.
ABSTRACT This is a summary of a study carried out in Chile to certify industrial kiln drying of r... more ABSTRACT This is a summary of a study carried out in Chile to certify industrial kiln drying of radiata pine to comply with the international phytosanitary standard ISPM 15. The drying tests were performed in 100-m3 industrial kilns located at four different sawmills of the VIII region in Chile. The objective was to develop a standard protocol to certify industrial drying of radiata pine depending on the drying schedule and wood thickness. In part, the results were used to develop a multiple regression equation that permits sawmills to select their drying schedules in such a way that the lumber can be officially stamped as both kiln-dried and heat-treated for international trade.
ABSTRACT The occurrence of internal checks and their relationship with anatomical structure and b... more ABSTRACT The occurrence of internal checks and their relationship with anatomical structure and basic density in three clones of Eucalyptus nitens plantation trees grown in the eighth region of Chile were studied. Two trees per clone were sampled. The number, radial location, and length of internal checks were determined in samples oven-dried at temperatures increasing from 50 to 100�C. Wood anatomical features including vessel frequency and diameter and annual growth ring width were measured by image analysis. Results show that internal checks were greater for clones with lower basic density. Internal check frequency decreased with height in the tree and increased from pith to bark. A low wood basic density was related to greater ring width and vessel frequency, which contributed to the development of internal checks.
This study deals with the effect of heat treatment on Pinus oocarpa specimens from forest plantat... more This study deals with the effect of heat treatment on Pinus oocarpa specimens from forest plantations in Colombia. The effects of two heat treatments at 170 and 190 °C for 2.5 h in saturated vapor were evaluated based on the color, dimensional stability, air-dry and basic densities, modulus of elasticity (MOE), and modulus of rupture (MOR) in static bending of samples. The evaluations were carried out following the Colombian Technical Standards NTC 290 and 663, and the color changes resulting from heat treatments were monitored using the CIE-Lab, as well as other standards from the literature. The results show that there was 2.4% and 3.3% mass loss of wood modified at 170 and 190 °C, respectively. The air-dry and basic densities were higher in 170 °C treatment than after 190 °C treatment, and the thermal modifications applied increased the dimensional stability of the treated wood. After treatment at 170 and 190 °C, the lightness to darkness (L*) was reduced by 10% and 22%; the a* c...
This paper studies the relationship between apparent density and some anatomical properties of Eu... more This paper studies the relationship between apparent density and some anatomical properties of Eucalyptus nitens such as vessel frequency, vessel area, ring width, fiber cell wall thicknesses, and fiber length. The study involved 29 trees from 10 families of Eucalyptus nitens cut from a 17-yr-old plantation in Southern Chile. The properties were determined along the radial direction of the trees by using X-ray equipment and at selected positions through microscope and fiber quality analyzer equipment. The results showed that the anatomical properties of E. nitens did not change gradually from pith to bark, but they were better described by dividing the tree radius into three different wood-zones referred as inner-, middle-, and outer-wood. The apparent density of E. nitens was dependent of the vessel area, cell wall area, ring width, and latewood width. The correlation coefficient between apparent density and vessels area was negative and the correlation coefficient between apparent...
This paper studies the relationship between apparent density and some anatomical properties of Eu... more This paper studies the relationship between apparent density and some anatomical properties of Eucalyptus nitens such as vessel frequency, vessel area, ring width, fiber cell wall thicknesses, and fiber length. The study involved 29 trees from 10 families of Eucalyptus nitens cut from a 17-yr-old plantation in Southern Chile. The properties were determined along the radial direction of the trees by using X-ray equipment and at selected positions through microscope and fiber quality analyzer equipment. The results showed that the anatomical properties of E. nitens did not change gradually from pith to bark, but they were better described by dividing the tree radius into three different wood-zones referred as
In order to evaluate evolution of physical and mechanical properties due to drying and heat modif... more In order to evaluate evolution of physical and mechanical properties due to drying and heat modification, a load of radiata pine wood was selected and properties were measured after each drying process. The results revealed interesting correlations between intrinsic factors and properties; the values of density were highly dispersed after drying or thermal treatment and uncorrelated with others parameters, but the minimum density values were kept constant after heat-treatment. Moreover, weight loss (WL) and moisture content (MC) were decreasing proportionally to the treatment intensity, due to wood-water interactions, cell wall changes and thermal degradation of wood fractions. WL and MC were reasonably correlated with the dimensional stability, improving the dimensional stability after drying treatments but keeping the same order of anisotropy. Regarding the wood stiffness (MOE), it was unaffected by the drying temperature, and the correlations between MOE and MC or WL appear to be acceptable, and the values of MC or WL did not adversely affect the MOE. However, the modulus of rupture was dropped during the drying process, obtaining three differentiated groups with a decrease of around 59% after thermal modification
The Effect of Wood Drying and Heat Modification on Some Physical and Mechanical Properties of Radiata Pine.
Wood and Fiber Science Journal of the Society of Wood Science and Technology, Dec 4, 2012
ABSTRACT This is a summary of a study carried out in Chile to certify industrial kiln drying of r... more ABSTRACT This is a summary of a study carried out in Chile to certify industrial kiln drying of radiata pine to comply with the international phytosanitary standard ISPM 15. The drying tests were performed in 100-m3 industrial kilns located at four different sawmills of the VIII region in Chile. The objective was to develop a standard protocol to certify industrial drying of radiata pine depending on the drying schedule and wood thickness. In part, the results were used to develop a multiple regression equation that permits sawmills to select their drying schedules in such a way that the lumber can be officially stamped as both kiln-dried and heat-treated for international trade.
ABSTRACT This is a summary of a study carried out in Chile to certify industrial kiln drying of r... more ABSTRACT This is a summary of a study carried out in Chile to certify industrial kiln drying of radiata pine to comply with the international phytosanitary standard ISPM 15. The drying tests were performed in 100-m3 industrial kilns located at four different sawmills of the VIII region in Chile. The objective was to develop a standard protocol to certify industrial drying of radiata pine depending on the drying schedule and wood thickness. In part, the results were used to develop a multiple regression equation that permits sawmills to select their drying schedules in such a way that the lumber can be officially stamped as both kiln-dried and heat-treated for international trade.
ABSTRACT The occurrence of internal checks and their relationship with anatomical structure and b... more ABSTRACT The occurrence of internal checks and their relationship with anatomical structure and basic density in three clones of Eucalyptus nitens plantation trees grown in the eighth region of Chile were studied. Two trees per clone were sampled. The number, radial location, and length of internal checks were determined in samples oven-dried at temperatures increasing from 50 to 100�C. Wood anatomical features including vessel frequency and diameter and annual growth ring width were measured by image analysis. Results show that internal checks were greater for clones with lower basic density. Internal check frequency decreased with height in the tree and increased from pith to bark. A low wood basic density was related to greater ring width and vessel frequency, which contributed to the development of internal checks.
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The Effect of Wood Drying and Heat Modification on Some Physical and Mechanical Properties of Radiata Pine.
The Effect of Wood Drying and Heat Modification on Some Physical and Mechanical Properties of Radiata Pine.