• 한국문화재보존과학회:학술대회논문집
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• 2005.11a
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• pp.290-295
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• 2005

본 실험은 경주 월성해자와 일정교지에서 발굴된 고목재를 시료로 사용하였다. 월성 해자 5점, 일정교지 2점으로 총 7점을 대상으로 수종분석과 연륜연대 해석을 실시하였다. 수종분석은 광학현미경을 사용하여 식별을 하였으며, 연륜연대 해석은 연륜측정후 연륜분석 컴퓨터프로그램과 그래프 일치도를 육안으로 비교하여 실시하였다. 7개의 시료 전부 밤나무였다. 밤나무는 현재 평남과 함남 이남에 분포하는 수종으로 특히 따뜻한 남부지방에 살기 적합한 수종이다. 각 시료간의 상대연도를 확인한 결과는 월성해자 목재의 수령은 $31{\sim}37$년 일정교지는 45년으로 확인 되었다. 월성해자의 각 시료들은 동시대이나 벌채기간은 6년 차이가 났다. 일정교지의 시료에서는 일치성을 확인하지 못했다.

• Journal of the Korean Wood Science and Technology
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• v.16 no.3
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• pp.65-71
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• 1988

캐나다가 미국산 활엽수재의 가장 큰 수입국이며 수입된 일부 제재목과 수입원목으로 제조된 단판중 일부는 유럽으로 재 수출되고 있다. 수입 물량적인면에서 캐나다는 다른 국가와의 격차는 좁혀지더라도 미국산 활엽수재의 제1위 수입국의 위치를 당분간 유지할 것이다. 유럽에서의 제재목 수요가 1973년부터 1983년간의 10년간에는 급진적으로 증가 되었지만 1984년에 는 갑자기 감소되었다. 이와같은 현상은 과거 유럽 전통가구에 소재(素材)를 많이 사용했지만 현재는 소재(素材)를 적게 사용하고 단판이나 인쇄한 종이를 붙인 파아티클 보오드(PB)를 더욱 많이 사용하고 있기 때문이다. 현재 유럽지역에서는 가구의 크기를 줄이거나 가구에 사용되는 원자재의 비용을 줄임으로 제품의 가격을 싸게하여 소비자에게 보다 경쟁력있는 가격으로 제품을 공급할려고 하고 있으며 활엽수재의 가격이 너무 비싸 가구제조업체들은 소재(素材)를 다른 것으로 대체하고 보다 값싼 수종을 모든 지역에서 찾고 있는 중이다. 태평양 연안국가에서의 미국산 활엽수재의 수입 물량은 계속 증가되어 미국산 활엽수 총 수출 물량의 약 23% 정도 된다. 자유중국과 일본에서 미국산 활엽수재를 가장 많이 수입하고 있다. 자유중국은 주로 수출용 가구부품및 가구에 사용되는 red oak와 white oak 가 주 수종이고 가구는 미국으로 재 수출하고 있다. 일본은 주로 black cherry, yellow poplar와 cotton wood를 수입하는데 수입량의 약 67%는 대패질한 건조 가공품이다. 자유중국에서와는 달리 일본에서의 미국산 활엽수의 용도는 일본산 활엽수의 대체수종으로 허용되고 있다. 앞으로 일본에서의 미국산 활엽수재의 수요는 일본 국내시장의 요인에 의해 좌우될 것인데 한정된 물량의 일본산 활엽수재와 온대 활엽수재의 요구에 영향을 받을 것이다.

• Journal of the Korean Wood Science and Technology
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• v.43 no.3
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• pp.295-303
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• 2015

Daewungbojeon hall of Magoksa temple is a korean traditional wood building well representing Joseon Dynasty architecture in the 17th century. The purpose of this study was to identify the wood species of 42 wooden elements collected from Pillar (Gidung), Head-penetrating tie (Changbang), Pyeongbang, Angle rafter (Chunyeo), End-angle rafter (Sarae) and Hwalju. According to the microscopical investigation, Pillar, Head-penetrating tie, Pyeongbang and Hwalju were identified as domestic hard pine species. However, Chunyeo were identified as either Zelkova serrata Makino or Gingko biloba L. and Sarae as exotic hard pine species. It might be related to the high replace rate of wood elements for the roof. Especially, exotic hard pine species seem to be replaced in recent years when Daewungbojeon hall was repaired.

• Journal of the Korean Wood Science and Technology
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• v.12 no.4
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• pp.36-46
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• 1984

In order to investigate the inhibitory index (I) and the effects of hot water extraction treatments and addition of accelerators on the index in hardening of Korean lignocellulosics, portland cement (Type I) and water system, hydration tests were carried out on 8 Korean lignocellulosics, namely, Pinus densiflora, Pinus rigida, Pinus koraiensis, Abies holophylla, Larix leptoiepis, Populus alba-glandulosa, rice husk and rice stalk with or without hot water extraction or chemical additives. The inhibitory index of Pinus densiflora and Pinus rigida found to be suitable under limited conditions for composite without any treatment. With hot water treatment rice husk, Pinus koraiensis, Larix leptolepis, and A hies holophylla were reclassified from not suitable to suitable under limited conditions. Combining hot water extraction with chemical addition of accelerator, calcium chloride of magnesium chloride, Populus alba-glandulosa, Larix leptolepis, and Pinus rigida became highly suitable.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.757-767
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• 2015

This study was conducted to investigate the effects of moisture content and particle size of sawdust on the fuel characteristics of wood pellets produced with Mongolian oak (Quercus mongolica, QUM), red pine (Pinus densiflora, PID) and larch (Larix kaempferi, LAK) sawdust using a flat-die pelletizer. Prior to produce wood pellets, the sawdust was controlled to the moisture content of 8, 11, 12% and was screened to the particle size of 2 and 4 mesh. In the analysis of its chemical composition, QUM had a high ash content, and PID and LAK contained large amount of lignin. In case of the fuel characteristics, PID pellets had the lowest moisture content of pellets (P-MC), and LAR pellets was found to have the highest bilk density (BD) and durability (DU). With the increase of moisture content of sawdust (S-MC), P-MC and DU of QUM, PID and LAK pellets increased, but BD of QUM and LAK pellets decreased. When size of sawdust used for the production of wood pellets decreased, P-MC and BD of LAK pellets and BD of QUM pellets increased. Decrease of particle size contributed to the increase of DU of QUM, PID and LAK pellets. In addition, BD and DU of QUM pellets produced with 12% S-MC sawdust increased as its particle size reduced. For LAK pellets, DU was not influence by particle size in the S-MCs of 10% and 12%, but increased with the decrease of particle size in the S-MC of 8%. Based on the results and economical aspects, 10% MC and 2 mesh paricle size for QUM sawdust and 12% MC and 2 mesh particle size for PID sawdust might be optimal conditions for pellets production, and fuel characteristics of wood pellets produced by the conditions greatly exceeded the minimum requirements for the $1^{st}$-grade wood pellets of the standard designated by Korea Forest Research Institute.

• Journal of the Korean Wood Science and Technology
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• v.37 no.6
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• pp.505-516
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• 2009

The effects of wood species, particle size of wood flours and coupling treatment on the mechanical properties of wood plastic composites (WPC) are investigated in this study. Chemical components of wood flour from 3 different wood species were analyzed by the chemical analysis. Wood flours of 40~60 mesh and 80~100 mesh were manufactured from Larix (Larix kaempferi Lamb.), Quercus (Quercus accutisima Carr.), and Maackia (Maackia amuresis Rupr. et Maxim). The wood flours were reinforced into polypropylene (PP) by melt compounding and injection molding, then tensile, flexural, and impact strength properties were analyzed. The order of alpha-cellulose content in wood is Quercus (43.6%), Maackia (41.3%) and Larix (36.2%). The order of lignin content in wood is Larix (31.6%), Maackia (24.7%), and Quercus accutisima (24.4%). The content of extractives in wood is in the order of Larix (8.5%), Maackia (4.4%), and Quercus accutisima (3.9%). As the content of alpha-cellulose increases and the lignin and extractives decreases, tensile and flexural strengths of the WPC increase. At the same loading level of wood flours, the smaller particle size (80~100 mesh) of wood flours showed highly improved tensile and flexural strengths, compared to the larger one (40~60 mesh). The impact strength of the WPC was not significantly affected by the wood species, but the wood flours of larger particle size showed better impact strengths. The addition of maleated polypropylene (MAPP) provided the highly improved tensile, flexural and impact strengths. Morphological analysis shows improved interfacial bonding with MAPP treatment for the composites.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.792-797
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• 2015

In this study, three softwood species were treated with water-soluble melamine resin by different concentration and treatment time under vacuum pressure for improving mechanical property, abrasion resistance, and incombustibility. After the treatment, a compreg was manufactured and then evaluated on physical properties. Additionally, incombustibility of compreg was determined by comparing with a wood that was treated by spraying a water-soluble fire retardant on surface. As concentration of resin increased, bending strength and Brinell hardness increased as well as abrasion resistance, but there was no correlation on treatment and mechanical properties by treatment time. The wood impregnated by water-soluble melamine resin under vacuum pressure showed better incombustibility than that of a water-soluble fire retardant sprayed wood. Therefore, this treatment could be used for improving incombustibility of wood.

• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.298-305
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• 2010

The effects of wood species, chemical components, filler loading level, filler particle size, and coupling agent on the water absorption property of the wood flour filled polypropylene (PP) composites were investigated in this study. After 500, 1,000, 1,500, 2,000, 2,500 and 3,000 hr water immersion, Quercus (Quercus accutisima Carr.) and Maackia (Maackia amuresis Rupr. et Maxim) showed significantly lower water absorption properties compared to Larix (Larix kaempferi Lamb.). As wood flour loading increases from 10 to 50 wt%, most wood species showed increased water absorption after a given immersion period. Particle size of wood flour proved to have very significant effects on water absorption of the composites. The effect of coupling agent was positive in terms of lowering water absorption of the composites. As the treatment level of coupling agent increases, the water absorption of the composites decreases. The lowest water absorption was obtained at the lower wood flour loading (Maackia), smaller particle size and by the addition of coupling agent. Thickness swelling of the composites shows close dependency on water absorption.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.701-713
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• 2015

A model was designed to identify wood species between Pinus densiflora for. erecta Uyeki and Pinus densiflora Sieb. et Zucc. using the near-infrared (NIR) spectroscopy in combination with principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA). In the PCA using all of the spectra, Pinus densiflora for. erecta Uyeki and Pinus densiflora Sieb. et Zucc. could not be classified. In the PCA using the spectrum that has been measured in sapwood, however, Pinus densiflora for. erecta Uyeki and Pinus densiflora Sieb. et Zucc. could be identified. In particular, it was clearly classified by sapwood in radial section. And more, these two species could be perfectly identified using PLS-DA prediction model. The best performance in species identification was obtained when the second derivative spectra was used; the prediction accuracy was 100%. For prediction model, the $R_p{^2}$ value was 0.86 and the RMSEP was 0.38 in second derivative spectra. It was verified that the model designed by NIR spectroscopy with PLS-DA is suitable for species identification between Pinus densiflora for. erecta Uyeki and Pinus densiflora Sieb. et Zucc.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.43-50
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• 2002

This paper describes experimental results on the utilization of some Korean oak woods for whisky aging barrel. Some anatomical characteristics as vessel diameter, ray spacing, ray height, existence of tyloses, water absorption and color change of alcohol during immersing of wood samples were examined. The oak woods used in this study were ring-porous. The type of ray was a compound ray consisted of uniseriate ray and broad ray. The ray parenchyma cells were almost procumbent, tyloses were presented in white oak(Quercus aliena, Quercus variabilis, Quercus dentata, Quercus mongolica), but absented in red oak(Quercus rubura). Density of wood samples decreased during immersing in alcohol. Alcohol color in Quercus dentata and Quercus aliena presented more darker than other samples. Water absorption of sapwoods was higher than that of heartwoods. Especially, red oak showed more higher water absorption than white oak. Consequently, Korean white oak woods can be used as the whisky aging barrel.