Timber Properties and Cellulose Crystallites Size in Pine Wood Cut in Different Sawing Patterns after Pretreatment with CH3COOH and H2O2 and Densification

One process to improve wood quality is densification or wood surface compression. Our study analyzed the changes in some basic properties of pine wood, including its anatomical structure, density, modulus of elasticity (MOE), and dimensions of cellulose crystallites, after densification following soaking pretreatment in CH3COOH and H2O2 at a concentration of 20%. Samples were sawn in radial and tangential directions for analysis of the wood. The results showed a change in the shape of tracheid cells from hexagonal to oval, as well as damage to the ray cell constituents on the tangential surface. The thickness decrease of the samples was in accordance with the target, which meant that spring-back was short. In general, the tangential boards had a higher density than the radial boards, with a lower MOE and crystallite dimensions. Our findings showed that the densified tangential board was stronger than the radial board.

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Effect of surface preparation on the wettability of heat-treated jack pine wood surface by different liquids

European Journal of Wood and Wood Products ◽

10.1007/s00107-012-0605-z ◽

2012 ◽

Vol 70 (5) ◽

pp. 711-717 ◽

Cited By ~ 16

Author(s):

Xianai Huang ◽

Duygu Kocaefe ◽

Yaman Boluk ◽

Yasar Kocaefe ◽

Andre Pichette

Keyword(s):

Wood Surface ◽

Surface Preparation ◽

Jack Pine ◽

Pine Wood ◽

Heat Treated ◽

Effect Of Surface

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Changes in the volume and proportion of large-sized pine wood quality classes in relation to the type of log manipulation

Forest Research Papers ◽

10.2478/v10111-010-0026-x ◽

2010 ◽

Vol 71 (3) ◽

pp. 311-314

Author(s):

Joanna Witkowska

Keyword(s):

Wood Quality ◽

Pine Wood

Zmiany miąższości i udziału klas jakości drewna wielkowymiarowego sosnowego w zależności od rodzaju manipulacji dłużyc

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Single-Sided Microwave Near-Field Scanning of Pine Wood Lumber for Defect Detection

Forests ◽

10.3390/f12111486 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1486

Author(s):

Mohamed Radwan ◽

David V. Thiel ◽

Hugo G. Espinosa

Keyword(s):

Wood Surface ◽

Near Field ◽

Field Measurements ◽

Slot Antenna ◽

Single Frequency ◽

Destructive Testing ◽

Pine Wood ◽

Structural Weakness ◽

Wood Grain ◽

Water Saturated

Defects and cracks in dried natural timber (relative permittivity 2–5) may cause structural weakness and enhanced warping in structural beams. For a pine wood beam (1200 mm × 70 mm × 70 mm), microwave reflection (S11) and transmission (S21) measurements using a cavity-backed slot antenna on the wood surface showed the variations caused by imperfections and defects in the wood. Reflection measurements at 4.4 GHz increased (>5 dB) above a major knot evident on the wood surface when the E-field was parallel to the wood grain. Similar results were observed for air cavities, independent of depth from the wood surface. The presence of a metal bolt in an air hole increased S11 by 2 dB. In comparison, transmission measurements (S21) were increased by 6 dB for a metal screw centered in the cavity. A kiln-dried pine wood sample was saturated with water to increase its moisture content from 17% to 138%. Both parallel and perpendicular E-field measurements showed a difference of more than 15 dB above an open saw-cut slot in the water-saturated beam. The insertion of a brass plate in the open slot created a 7 dB rise in the S11 measurement (p < 0.0003), while there was no significant variation for perpendicular orientation. By measuring the reflection coefficient, it was possible to detect the location of a crack through a change in its magnitude without a noticeable change (<0.01 GHz) in resonant frequency. These microwave measurements offer a simple, single-frequency non-destructive testing method of structural timber in situ, when one or more plane faces are accessible for direct antenna contact.

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Are Rays and Resin Canals Causal Sites for Intra-Ring Checking in the Wood of Pinus Radiata?

IAWA Journal ◽

10.1163/22941932-90000214 ◽

2009 ◽

Vol 30 (2) ◽

pp. 189-198 ◽

Cited By ~ 2

Author(s):

Hema Nair ◽

Brian Butterfield ◽

Sandra Jackson

Keyword(s):

Comparative Study ◽

Pinus Radiata ◽

Wood Quality ◽

Radiata Pine ◽

Structural Features ◽

Linear Arrangement ◽

Pine Wood ◽

Kiln Drying ◽

Tissue Area ◽

Resin Canals

Pinus radiata D. Don (radiata pine) wood can develop a wood quality defect called ‘intra-ring checking’ (checks) during kiln drying. A study was conducted to examine if rays and resin canals were the initiation sites of checks, and if the presence of the rays and resin canals increased the susceptibility of radiata pine wood to checking. The structural features associated with checking were observed in images of thirteen oven-dried radiata pine disks. Six of the sixty checks observed were associated with rays and resin canals. It is clear from the observations that rays and resin canals could not be the primary sites for check development. A comparative study showed some differences between the checked and non-checked wood with respect to rays and resin canals. Checked wood showed a higher amount of tissue area occupied by rays than the nonchecked wood. Hence, it is possible that rays can influence the tendency of wood to check. Such a relationship was not seen with respect to resin canals. However, a difference in the arrangement of resin canals was observed between checked and non-checked wood. Checked wood showed a scattered arrangement of resin canals, while the non-checked wood showed a linear arrangement.

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Formation of 7-Ketodehydroabietic Acid at the Radiata Pine Wood Surface. and its Effect on Wood Yellowing

Journal of Wood Chemistry and Technology ◽

10.1080/02773819208545238 ◽

1992 ◽

Vol 12 (3) ◽

pp. 323-333 ◽

Cited By ~ 3

Author(s):

Kathryn B. Anderson ◽

Michael J. Collins ◽

Robert A. Franich ◽

Hank W. Kroese

Keyword(s):

Wood Surface ◽

Radiata Pine ◽

Pine Wood

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Integral assessment of pine wood quality in provenance plantations of Archangelsk region

Resources and Technology ◽

10.15393/j2.art.2008.1828 ◽

2008 ◽

pp. 43-48

Author(s):

S A Korchagov ◽

S E Gribov ◽

Yu M Andreev ◽

N A Kljukvina

Keyword(s):

Wood Quality ◽

Pine Wood ◽

Integral Assessment

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Properties of Oak Roundwood with and without Frost Cracks

Forests ◽

10.3390/f11050538 ◽

2020 ◽

Vol 11 (5) ◽

pp. 538

Author(s):

Przemysław Mania ◽

Arkadiusz Tomczak

Keyword(s):

Compressive Strength ◽

Modulus Of Elasticity ◽

Wood Quality ◽

Frost Damage ◽

Quercus Petraea ◽

Modulus Of Rupture ◽

Mechanical Parameters ◽

Entire Volume ◽

Oak Wood ◽

Tangential Directions

The aim of this study was to examine certain properties of sessile oak wood (Quercus petraea (Matt.) Liebl.) with frost cracks, such as density (ρ), modulus of rupture (MOR), modulus of elasticity (MOE), and compressive strength in all anatomical directions and to compare it with control trees without frost cracks. Oak with frost cracks had a higher wood density (ρ = 765 kg × m−3) than the control (ρ = 650 kg × m−3). However, despite its lower density, the control oak was characterized by noticeably better mechanical parameters, with the exception of the compressive strength in radial and tangential directions. Differences in mechanical parameters reached up to 26%. The tests were performed on wood taken from trees with frost cracks that formed over 10 years to several decades ago. Frost cracks can render wood vulnerable to fungi growth, which leads to rotting and discoloration. Differences in strength were found on samples with no visible signs of decay, as they were cut at a distance from the crack. Nonetheless, the observed differences in strength allowed us to conclude that the shreds of fungi, as well as decay, may occur in the entire volume of the frost-damaged log. Such wood is, therefore, of a lower quality than that made of logs without any frost damage. Trees with frost cracks should be progressively be felled during the periodic intermediate cutting, as their wood quality may systematically deteriorate over the years.

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Changing the face of short fiber –a review of the eucalyptus revolution

TAPPI Journal ◽

10.32964/tj14.6.353 ◽

2015 ◽

Vol 14 (6) ◽

pp. 353-359 ◽

Cited By ~ 6

Author(s):

PETER W. HART ◽

RICARDO B. SANTOS

Keyword(s):

Fossil Fuels ◽

Wood Quality ◽

Short Fiber ◽

Fiber Volume ◽

Private Industry ◽

High Productivity ◽

Paper Manufacturing ◽

Short Rotation ◽

Eucalypt Plantations ◽

Eucalyptus Plantations

Eucalyptus plantations have been used as a source of short fiber for papermaking for more than 40 years. The development in genetic improvement and clonal programs has produced improved density plantations that have resulted in fast growing, increased fiber volume eucalypts becoming the most widely used source of short fibers in the world. High productivity and short rotation times, along with the uniformity and improved wood quality of clonal plantations have attracted private industry investment in eucalypt plantations. Currently, only a handful of species or hybrids are used in plantation efforts. Many more species are being evaluated to either enhance fiber properties or expand the range of eucalypt plantations. Eucalyptus plantations are frequently planted on nonforested land and may be used, in part, as a means of conserving native forests while allowing the production of high quality fiber for economic uses. Finally, eucalypt plantations can provide significant carbon sinks, which may be used to help offset the carbon released from burning fossil fuels. The development and expansion of eucalypt plantations represents a substantial revolution in pulp and paper manufacturing.

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