• Journal of the Korean Wood Science and Technology
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• v.37 no.5
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• pp.451-458
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• 2009

Anatomical comparison of 8 North American species of Abies was executed to provide taxonomic information. The species of eastern (balsam and Fraser fir) and western (Pacific silver, white, grand, subalpine, California red, and noble fir) were found to be separated on the basis of crystals and color of contents in ray parenchyma cells and ray height. In eastern species, crystals in ray parenchyma cells were absent and ray parenchyma cell contents were colorless to very light. These two eastern species were further characterized by the absence of uniseriate rays exceeding 25 cells in height. In western species, only subalpine fir had colorless to very light contents but the remaining five species have dark contents in ray parenchyma cells. Crystals were absent to extremely sparse in Pacific silver fir, somewhat frequent in noble fir, frequent in grand and California red fir, and very frequent in white fir. Uniseriate rays exceeding 25 cells in height were regularly found in grand and California red fir but absent in white and noble fir.

• Journal of the Korean Society of Clothing and Textiles
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• v.38 no.2
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• pp.201-215
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• 2014

This study explores the kinds and types of dyes used in the Joseon Dynasty. Some literature including "Sanga Yorok", "Gyuhap Chongseo", "Imwon Gyeonjeji" were reviewed for this purpose. The findings are as follows. The colors obtained from the dyes were divided into seven color series, such as red, yellow and orange, green, blue, purple, brown, gray and black. These are practical color categories differed from abstract five cardinal colors [五方色]. The diachronic dyes used during the Joseon Dynasty were safflower and Japanese alder bark for red, indigo leaves for blue, gromwell for purple, chestnut tree bark for brown. The representative dyes used in the late Joseon Dynasty were safflower and sappan wood for red, wild pear tree bark and Pentapetes phoenicea for yellow and orange, indigo leaves for blue, sappan wood and gromwell for purple, mulberry tree for brown, and Chinese ink for gray. Common dyes used both in Joseon and China were safflower and sappan wood for red, pagoda tree blossom for yellow, a combination of pagoda tree blossom (or Amur cork tree) and indigo leaves (or sediment) for green, indigo leavers or sediment for blue, sappan wood and hollyhock for purple, and a combination of indigo leaves and Galla Rhois for gray and black.

• Journal of the Korean Wood Science and Technology
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• v.38 no.2
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• pp.108-116
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• 2010

This paper explains the effects of wood drying on treatability (as determined by water uptake) of Japanese red pine (Pinus densiflora S. et Z.) at the sevenmoisture content (MC) levels above and below the fiber saturation point (FSP). According to the experimental results, it was found that water uptake (as the percentage of void volume filledwith distilled water, VVF%) was influenced by level of moisture content and percentage of void volume filled was improved effectively by kiln drying process. A significant relationship between moisture content and treatability was established. Permeability and liquid uptake were decreased above the FSP due to the effect of the less void space available in wood. Even though increased liquid uptake was observed at lower moisture content, no significant differences was observed moisture content below 20%. Therefore, this species need to be initially dried below FSP before treated with liquids. But drying moisture content below 10% might not be economical for the commercial purpose comparing drying the wood between 10 and 20% moisture content. The result of this study inferred that the treatability of pine wood can be improved by reducing the moisture content up to a certain level of 10~20% for allowing better performance.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.19-23
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• 1977

Tropical hard wood produces a number of extracts, especially hot-water extracts. The lignin content in the two kinds of bangkirai and red lauan belonging to genus Shorea, was as high as in temperate zone soft wood, mangrove wood of genus Rhizophara contained it on the same level as temperate zone hard wood and keruing of genus Dipterocarpus was in between the two kinds of bangkirau and red lauan, and keruing wood. The xylose content of saccharose composition in the tree of genus Shorea, was as low as in needle-leaved trees, mangrove wood contained it on the same level as broad-leaved trees and the xylose content in keruing wood was in between the above two kinds of wood. The total retrieving rate of alditol acetate acetificated with sulphuric acid and acetic anhydride, did not reach 100%, even if it was supplemented. There was no difficulty in analyzing alditol immediately after acetification but, when it was left for four or five days, the acetificated alditol acetate was dissolved. The pyridine alditol acetificated with pyridine and acetic anhydride, showed the same result.

• Journal of the Korean Wood Science and Technology
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• v.27 no.4
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• pp.15-19
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• 1999

Three wood coffins of Chosun Dynasty period buried about 450 years ago were excavated in the sound condition in Andong area in the early 1998. The proprietors of wood coffins were grandparents, Mr. Myoung Jong Lee and Mrs. Mun, and their grandson, Mr. Eung Tae Lee, and the social standing of their family was known to belong to the nobility in those days by the clan genealogy. All the wood coffins investigated through light microscopy had same anatomical characteristics as follows: abrupt to somewhat abrupt tracheid transition from earlywood to latewood; normal longitudinal and horizontal resin canals with thin-walled epithelium; tylosoids in resin canals; bordered pits frequently in 1 row on radial walls of tracheids; 1 or 2 window-like pits per cross-field; uniseriate and fusiform rays; heterogeneous rays composed of body ray parenchyma cells and marginal ray tracheids or homgeneous rays composed of only ray tracheids; dentate ray tracheids; occasional trabeculae traversing tracheids in radial direction. Based on theses microscopic characteristics, all the wood coffins were identified to be Korean red pine (Pinus densiflora) or Korean black pine (Pinus thunbergii). Korean black pine growing naturally in coastal area might not be probable because the site of excavation, Andong area, was mountainous and inland area of Korea Thus, Korean red pine was thought to be the possible species for the wood coffins because of its natural distribution through the Korean Peninsula and the easy availability.

• Journal of the Korean Wood Science and Technology
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• v.29 no.1
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• pp.52-59
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• 2001

The fixation characteristics of CCA and CCFZ in Japanese red pine, Japanese larch, and ezo spruce sapwood were compared at various temperatures and fixation conditions (drying and nondrying fixation). Fixation was monitored by the rates of reduction of hexavalent chromium to trivalent one, and optimal fixation time was estimated based on the results. The rate of fixation was highly temperature dependent, and the fixation rate of treated wood conditioned under nondrying conditions was much more faster than that under drying conditions, especially when the moisture content of treated wood was below fiber saturation point. Preservative types affected fixation; CCA-Type B had the highest fixation rate, followed by CCA-Type C and then CCFZ. The differences in fixation rates of preservative components were also observed among wood species; Japanese red pine fixed the fastest, followed by Japanese larch and then ezo spruce. Time required to complete fixation according to the fixation temperature could be predicted successfully using the regression equations between the temperatures and fixation time, regardless of conditioning methods, preservative types, and wood species.

• Journal of the Korean Wood Science and Technology
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• v.43 no.4
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• pp.429-437
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• 2015

It has been known that acetylation improves the dimensional stability of wood. Liquid phase acetylation is more popular than gas-phase acetylation for the effectiveness of weight gain of wood. In this study domestic red and Korean pine specimens were liquid phase acetylated and their physical properties, such as density, bending strength, dimensional stability etc., were investigated. Acetylation increased the average weights of red and Korean pine specimens by 10.4% and 9.2%, respectively, and their average oven-dry densities were increased by 6.9% and 4.6%, respectively. Acetylation did not influence on modulus of rupture (MOR), modulus of elasticity (MOE) and dynamic MOE (DMOE). The average percentage reduction in hygroscopicity (PRH) of red and Korean pine specimens were respectively 20.6% and 13.8%, while the average percentage reduction in water soaking (PRW) were respectively 20.0% and 8.5%. Thus it can be concluded that the liquid acetylation improved the dimensional stability of red pine specimens more than that of Korean pine specimens.

• Journal of the Korean Wood Science and Technology
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• v.50 no.1
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• pp.1-11
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• 2022

To evaluate the bearing strength of red pine cross-laminated timber (CLT) with self-tapping screw (STS), which is widely used as a fastener for connection in CLT building, the bearing test was conducted. Accoring to the STS's diameters (8, 10, 12 mm), the bearing test specimens with half hole were manufactured. Bearing strength was compared and reviewed in consideration of the configuration in STS and the loading direction to the grain of red pine. As a result of the bearing test on the STS's diameter, the yield bearing load increases as the larger diameter of the STS in all directions of the red pine. The bearing strength of the thread part (thread + tip) was higher than the shank part (shank + shank cutter). In compared with the directions to the grain of red pine, the bearing strength of the cross section parallel to the loading direction was the highest, and the tangent section was the lowest bearing strength. The average bearing strength of the loading direction in parallel to the grain was 23.43 MPa, which was about 45% higher than the average 16.16 MPa in perpendicular to the grain. The predicted bearing strength calculated by Eurocode (EN) and Korean Building Code (KBC)'s equation was lower than the experimental value. It is nessesary to propose the new equations of bearing strength reflected the configuration information of STS.

• Journal of the Korea Furniture Society
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• v.19 no.3
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• pp.172-179
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• 2008

The objective of this study was to investigate the influence of the water repellents' treatment on the water absorptivity and the dimensional stability of Korean red pine wood(Pinus densiflora). The alkylketene dimer(AKD), fluororesin emulsion(Wood-seal, WS), and paraffin wax emulsions(PW25, PW40, and PW1200) were used as water repellents. PW40 and WS were proved as excellent water repellents for pine wood, because the samples treated with these agents showed high contact angles and large reduction in water absorptivities. Also, the dimensional stability(antiswelling efficiency) of pine wood was considerably improved by water repellents treatments, such as PW40 and WS at the pressure of 2MPa. The water repellent treated woods with WS, PW40, and PW1200 at the pressure of 2MPa were relatively stable to the wet-dry cyclic leaching test.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.327-336
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• 2013

Anatomical characteristics of White Jabon (Arthocephalus cadamba) and Red Jabon (Arthocephalus macrophyllus) were investigated by IAWA hardwood feature list. Both species were diffuse-porous, and radial multiple pore with 2~3 rows was mostly observed. Tangential diameter of vessel lumina was 100 to $200{\mu}m$, and vessels per square millimeter were 5 to 20. White Jabon has more vessels than Red Jabon. The number of solitary pore per square millimeter in both species was similar, but more pore multiple was observed in White Jabon. Axial parenchyma diffuse was observed in both species, but axial parenchyma of White Jabon was hardly identified on the cross section. Rays were classified into "body ray cells procumbent with over 4 rows of upright/square marginal cells" type and partly "all ray cells upright and/or square" type on radial section. Ray width 1 to 3 cells and 1 to 2 cells observed in White Jabon and Red Jabon, respectively. Ray height of White Jabon was $420{\mu}m$ and Red Jabon $474{\mu}m$. Fiber length was the range of 900 to $1,600{\mu}m$ in both species, and it showed a tendency to increase from pith to bark. Consequently, it is considered that pore multiple, ray width and axial parenchyma are to be suggested the keys for identification of both species.