• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.1-9
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• 1995

This study was carried out to experiment the dimensional stabilization of woods of red pine (Pinus densiflora S. et Z.) and sugi(Cryptomeria japonica D. Don) by vacuum impregnation of polyehtylene glycols(PEG) with mo. wt. 200, 400, 600, 1000; polypropylene glycols (PPG) with mo. wt. 425,725 ; PEG-acryloylates, and PPG-acryloylates synthesized, and then by water soaking. The results obtained are as follows: 1. The density of sapwood and heartwood was different from each other in both species. 2. The PEG and PEG-macromers with lower molecular weight by impregnation has increased the density of wood specimens more higher, thereby caused their higher volume expansion, and those with higher molecular weight than 600 has tended to down their density increment. 3. Before and after water soaking, the density decrease of specimen impregnated was high in woods impregnated with simple PEG and PPG, while lower in specimens impregnated with PEG-macromers and PPG-macromers. 4. So PEG-macromer was expected to hold the original dimension of decayed wood for antiques, but it was necessary to develop another penetration method as well as aqueous solvent.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.18-26
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• 1995

국내 합판 산업계는 오랫동안 남양재 활엽수를 주로 사용하여 왔으나, 환경 보존적인 측면에서 열대재의 벌채를 규제하는 등 여러 요인으로 인하여 합판용 원목의 수입이 어려워지고 있다. 이에 대응하기 위하여 합판용 원목을 침엽수재로 대체할 필요가 있으며, 침엽수 합판 제조를 위한 기초 자료를 제공하기 위하여 본 연구를 수행하였다. 공시 수종은 국내에서 조림한 낙엽송과 시베리아산 낙엽송 및 뉴질랜드산 라디에타 소나무였으며, 공시원목으로부터 얻어진 단판의 품질과 이들 단판으로 제조한 합판의 접착력과 휨강도를 조사하였다. 이면 할렬실험에서 시베리아산 낙엽송은 다른 수종에 비해 할렬 밀도가 낮게 나타났다. 단판 품질은 접착력 및 휨강도에 거의 영향을 미치지 않았으나 합판의 휨강도에서는 심재와 변재에 따른 차이가 있음을 알 수 있었다. 이는 합판제조사 심재와 변재를 구별하여 사용할 필요가 있었다. 라디에타 소나무의 변재부로 만든 합판 MOR은 다른 수종에 비해 우수하게 나타났다. 접착력 실험에 있어서는 페놀 접착제를 사용하여 만들어진 합판만이 구조용으로써 사용할 수 있음을 알았다. 목파율은 동일 수종 합판에서는 라디에타 소나무 구성이 가장 높게 나타났으며, 이수종(異樹種) 합판에서는 표판을 국산 낙엽송, 심판을 라디에타 소나무를 사용하여 만든 합판에서 가장 높게 나타났다.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.33-38
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• 1995

The rates of fixation of CCA-Type B and CCFZ in blocks of radiata pine sapwood were compared at various temperatures and conditioning methods (drying and nondrying conditioning). Also the time required to proper fixation of preservative components in the treated wood was estimated. Fixation was monitored by the rates of depletion of free hexavalent chromium in the cell lumens in the teated blocks. The rate of preservative fixation in wood was highly temperature dependent. The fixation rate was considerably accelerated by means of heating and complete fixation of hexavalent chromium was achieved within about 12 hours by heating at $60^{\circ}C$. The moisture content of treated wood during fixation apparently played an important role in the fixation process. The fixation rate of treated wood conditioned in nondrying conditions was much more faster than that of treated wood conditioned in drying conditions. particularly when the moisture content of treated wood was below fiber saturation point. Time required to full fixation could be predicted successfully using the fixation temperatures applied since the correlation between the fixation temperature and the fixation time was excellent. regardless of conditioning methods.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.123-129
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• 2008

One of the sapstain fungal species isolated from the stained sapwood of a Japanese black pine in Korea was characterized. The fungal species is tolerant to cycloheximide and has Petosum-like synnema and Sporothrix type synanamorph which are found in the anamorphs of the Ophiostoma piceae complex group. But the species could not form perithecia on MEA. Based on cultural and morphological properties and analysis of the $\beta$-tubulin gene sequence, the fungal species was identified as Ophiostoma quercus. Here, we report mycological characteristics of the anamorphic stage of Ophiostoma quercus isolated in Korea.

• Journal of the Korean Wood Science and Technology
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• v.37 no.5
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• pp.421-425
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• 2009

This research investigates the effect of copper retention on copper leaching in wood treated with copper-based preservatives. Radiata pine (Pinus radiata D. Don) sapwood samples were ground in a Wiley mill equipped with a 20-mesh screen. The ground wood was vacuum-treated with various concentrations of alkaline copper quat (ACQ), bis-(N-cyclohexyl-diazeniumdioxy)-copper (CB-HDO), and copper azole (CUAZ). The treated samples were conditioned at $70^{\circ}C$ and 100% RH for 72 hours. The samples were leached by using the distilled water for four weeks, and the copper contents in each sample were measured by X-ray spectroscopy. As expected, the copper leaching was increased with increasing of copper retention. The copper leaching from the ACQ and CB-HDO treated samples were gradually decreased with increasing copper retention: however, the copper losses from the CUAZ treated samples appeared to be proportionally increased with the increase in copper retention in all retention levels tested. The results indicate that at the conditions of the same copper retention ACQ and CB-HDO treated wood have a better leaching resistance compared to CUAZ treated wood.

• Journal of the Korea Furniture Society
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• v.11 no.1
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• pp.13-23
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• 2000

This study was carried out to investigate the wood properties for development the proper uses of lesser-known tree species. The tested species are Kebambang(Pentace sp.), Bawang-bawang(Dysoxylum alliaceum Bl .), Garu buaya( Gonystylus brunescens A. Shaw)grown in Indonesia. fundamental wood properties such as anatomical, physical, mechanical and chemical properties and characteristics related to wood processing were examined. The results are summarized as follows : The woods of these species are diffuse porous, coarse textured, and interlocked grained. The heartwood of Kebambang is distinguished clearly to the sapwood, but the heartwood of other species are not distinguished clearly to the softwood. The woods of Kebambang and Bawang-bawang have the moderate weight density and the low strength properties, but Garu buaya has the high weight density and the high strength properties. The woods of these species has high shrinkage. The sawing characteristics of Kebambang are excellent but the other species are moderate. The machining characteristics by planer and drying characteristics of these species are moderate. These woods has poor characteristics in bending processing and decay durability. The wood of Bawang-bawang has high content of the extractives and lignin.

• Journal of the Korean Wood Science and Technology
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• v.36 no.2
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• pp.20-28
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• 2008

This study was carried out to provide the so-called circumferential slicing method for investigating radial distributions of the tangential strains and of moisture contents within the log cross section (LC) of Kalopanax pictus during indoor drying it. While the heartwood showed an almost uniform moisture content distribution in the range of about 50~55% in case of the green wood, it has gradually decreased toward the outer side, showing about 19% of moisture content difference from the innermost slice. Although the moisture gradient along the radial direction has gradually become gentle as drying progresses, the sapwood of the outer side represented the moisture contents below the fiber saturation point after 24 hours of drying while the heartwood in the inner part showed the moisture contents higher than the fiber saturation point. The pith side was laid under the tensile stress after 24 hours of drying, and then gradually decreasing toward the bark side, and showed the distribution being switched again to the tensile stress on the bark side. As the drying has progressed, this trend got more intensified, and finally showed the U-shaped distribution model after 48 hours of drying. The circumferential slice test is considered to be suitable in quantitatively determining the tangential strains and moisture content within a LC.

• Journal of the Korean Wood Science and Technology
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• v.37 no.3
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• pp.231-238
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• 2009

Red pine (Pinus densiflora) has been used for structural wood members of Korean traditional residence (HANOK) and historic wooden structures. For these constructions, generally, natural drying has conducted for long time; however, unless drying is conducted sufficiently, it could cause several drying defects such as check or warping. Shrinkage changes of red pine species for small clear specimens and big-size specimens according to the conditions of moisture contents, were examined. For the estimation of volumetric shrinkage at a special moisture content, it was more precise to divide the range of moisture contents into two groups, green to air-dry and air-dry to oven-dry. The volumetric shrinkage had no difference with specimen sizes in sapwood, but decreased as specimen size increased in heartwood.

• Journal of the Korean Wood Science and Technology
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• v.45 no.2
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• pp.195-201
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• 2017

This study was conducted to evaluate the resistance of heat-treated wood using the catalyst to decay caused by fungi for sapwood and heartwood of two tree species, Korean red pine (Pinus densiflora) and Japanese larch (Larix kaempferi), respectively. Wood samples were immersed for 10 min in sulfuric acid (7.5%) and then heat-treated at $130^{\circ}C$ for 90 min. Fomitopsis palustris, a brown-rot fungus, was used to examine the decay resistance of Korean red pine and Japanese larch wood. Weight and density of wood from the all conditions increased after heat treatment using the catalyst. Weight loss after decay resistance test was also dropped with a heat treatment. The lowest weight loss indicated at heat-treated heartwood of Japanese larch. Heat treatment using the catalyst effectively increased the resistance of wood to decay caused by fungi.

• Journal of the Korean Wood Science and Technology
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• v.31 no.6
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• pp.55-59
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• 2003

The fixation and leaching characteristics of chromated copper arsenate (CCA Type C) and chromium- copper-fluoride-zinc (CCFZ) in domestic softwood (Japanese red pine, Korean pine, and Japanese larch) sapwood were investigated using the expressate method to follow chromium fixation and the American Wood-Preservers' Association (AWPA) leaching procedure to determine leaching properties after fixation. The rates of fixation were affected by preservative types; CCA was fixed much faster than CCFZ for all species evaluated. There were definite differences in the fixation rates of different species, with Korean pine requiring shorter to fix than the other species evaluated. Chromium fixation was greatly enhanced by elevated temperatures, and fixation time can be estimated according to fixation temperatures applied. The percentage of arsenic and zinc leached from domestic softwoods was relatively high compared to chromium and copper, indicating that there is still a relatively high unfixed arsenic and zinc components after complete chromium fixation in CCA-and CCFZ-treated samples, respectively.