• Journal of the Korean Wood Science and Technology
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• v.15 no.2
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• pp.16-25
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• 1987

This study was carried out under controlled laboratory conditions in order to investigate the relative durability to decay of 6 Quercus species. The relative durability to decay was expressed by the percentage of weight loss by Lentinus edodes and Pleuratus ostreatus. The results obtained could be summarized as follows: 1. The most decay-resistant parts by L. edodes were heart wood of Q. sarrata TH. and sap wood of Q. aliena BL. and the least decay-resistant parts were heart wood of Q. acutissima C. and sap wood of Q. dentata TH.. 2. The most decay-resistant parts by P. osteratus were heart wood of Q. serrata TH. and sap wood of Q. aliena BL. and the least decay-resistant parts were heart wood of Q. variabilis BL. and sap wood of Q. dentata. TH.. 3. The percentage of weight loss in 6 Quercus species by section-height was not a consistent variation. 4. Putting these results together, Quercus aliena BL, could be regarded as the most decay-resistant by L. edodes and P. osteratus under normal condition among 6 Quercus species.

• Journal of Conservation Science
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• v.7 no.2
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• pp.60-67
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• 1998

The effects of moisture content (MC) and diffusion period on the diffusion of boron from borate rod through Pinus densiflora and P. koraiensis were investigated as a preliminary research of integrated remedial treatment for heritage wooden structures using borate rod. After equilibrating MCs of samples (15, 25, and 40%), borate rod (1,000 mg) was inserted into the sample, and stored for diffusion of boron at room temperatures ($23^{\circ}C$) for 2, 4, 8, and 12 weeks. Wafers were serially cut at constant intervals from rod treatment point and the boron penetration through longitudinal and transverse direction was measured by staining with boron indicator. For boron diffusion, MC above fiber saturation point was needed, and the diffusion rates increased with time. The fastest rates of diffusion were observed in longitudinal direction, followed by the radial and then the tangential direction. The rates of diffusion in all directions were the fastest in P. koraiensis. In P. densiflora, the diffusion rates through heartwood was faster than that in sapwood in longitudinal direction and vice versa in transverse direction. Based on the best result of this study, optimal space between rod insertion points could be recommended as follows; approximately 120 mm for P. koraiensis and heartwood of P. densiflora, 60 mm for sapwood of P. densiflora in longitudinal direction, and approximately 30 mm for all species tested in transverse direction. However, the effect of rod size and long-term exposure for diffusion on boron movement should be fully investigated for the accurate evaluation of optimal space between rod holes.

• 대한치주과학회:학술대회논문집
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• 2007.11a
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• pp.150-151
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• 2007

• YAKHAK HOEJI
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• v.43 no.5
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• pp.553-558
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• 1999

Six flavonoids were isolated from the heartwood of Maackia fauriei. On the basis of spectroscopic evidences, the structure of these compounds were established as 4'-7-dihydroxyflavone, genistein, retusin, afromosin, dehydroferreirin and 3'-methoxydaildzein.

• Korean Journal of Human Ecology
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• v.22 no.6
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• pp.687-699
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• 2013

This study was carried out to investigate the antifungal activity and house dust mite repellent effect of cotton and silk fabrics dyed with Juniperus chinensis heartwood extracts by hot-water and methanol. The chemical composition of Juniperus chinensis heartwood extracts by hot-water and methanol was analyzed by GC-MS. In the case of antifungal activity, dyed fabrics with hot water extract had no effect against chaetomium globosum fungus. But showing no growth in fabrics dyed with methanol extract, dyed fabrics with methanol extract showed very excellent antifungal activity. Silk fabric dyed with methanol extract showed excellent house dust mite repellent effect of 94.3%~96.0% against dermatophagodes farinae. The composition of Juniperus chinensis heartwood extracts from hot-water and methanol was different. There were no terpene and its analogue peaks in hot-water extract. However there were terpene and its analogue peaks in methanol extract. From these GC-MS results, terpene was identified in methanol extract of Juniperus chinensis heartwood. Efficient ingredient of antifungal activity and house dust mite repellent effect was assumed terpene.

• Journal of the Korean Wood Science and Technology
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• v.29 no.2
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• pp.133-139
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• 2001

The structures of six flavonoids isolated from heartwood of Prunus sargentii(Rosaceae) were analyzed by Mass and NMR spectrometry. These flavonoids were grouped into dihydroflavonol, flavanone, and flavanone glycoside, and identified as follows : 3,3',4',5,7-pentahydroxyflavanone(taxifolin) as a dihydroflavonol, 5-hydroxy-7-methoxyflavanone(pinostrobin), 4',5,7-trihydroxyflavanone(naringenin), 3',4',5,7-tetrahydroxyflavanone(eriodictyol), 5,7-dihydroxyflavanone(pinoccmbrin) as a flavanone and 7-hydroxyflavanone 5-O-${\beta}$-D-glucopyranoside(verecundin) as a flavanone glycoside.

• 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.28 no.2
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• pp.19-24
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• 2000

Effects of the cross-sectional dimension and moisture profile of wood specimens on the ultrasonic sound velocities of radiata pine heartwood and sapwood. Each moisture profile model specimen was made by composing five wood pieces with various moisture contents. As the cross-sectional dimensions decreased the ultrasonic velocities of both heartwood and sapwood decreased by 4~8%. In the ultrasonic signals transmitted through the specimens low frequency components more dominated than high frequency components as the dimension of cross section increased. The specimens with the same average MCs and different moisture profiles showed different ultrasonic velocities. By plotting the ultrasonic velocities against the average moisture contents of the inner three pieces of the moisture profile model specimens it was revealed that three distinct plot patterns existed.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.279-282
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• 2010

스티로폼샌드위치패널은 건식공법의 시공편리성, 경제적인 공사비용, 뛰어난 단열성능으로 공장이나 창고건축물을 중심으로 많이 사용되고 있다. 그러나 스티로폼의 여러 가지 장점에도 불구하고 화재에 취약한 단점이 있어 최근 난연성능이 보완된 난연스티로폼패널의 사용이 증가하고 있다. 최근 건축현장에서, 가짜 난연스티로폼패널 사용이 문제되고 있으나 난연성능의 현장 확인에 어려움이 있고 콘칼로리미터 등의 난연성능평가에 시간과 비용이 소요된다. 본 연구에서는 콘칼로리미터를 통해 난연성능이 확보된 난연 스티로폼패널의 심재와 일반스티로폼패널 심재를 대상으로 근-적외선 분광분석을 수행하여 난연성능의 유무에 따라 상이하게 나타나는 고유스펙트럼 흡수를 측정하였다. 각 제품마다 측정된 고유스펙트럼은 통계처리를 통하여 난연스티로폼의 진위여부를 현장에서 구별할 수 있음을 확인하였으며, 비용효율이 높은 현장평가방법으로의 적용이 가능함을 실험을 통해 입증하였다.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.6
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• pp.121-128
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• 2019

There is a big move to build zero-energy buildings in the form of passive houses that reduce energy waste worldwide. Korea has set a goal of reducing its greenhouse gas emissions by 37% by 2030 through the activation of green buildings, such as strengthening the energy levels of new buildings and improving the energy efficiency of existing buildings. The use of insulation with high insulation performance is one of the key technologies to realize this, and vacuum insulation is the next generation insulation that blocks the energy flow of the building. In this study, we measured the bonding structure of dry and wet processing glass fiber core materials and compared the insulation performance of vacuum insulation panel. In addition, the insulation performance of vacuum insulation panel was measured according to the thickness of the laminated core. It can be confirmed that the lamination structure of the core and the lamination thickness are important factors for the heat insulating performance of the vacuum insulating panel.