• Journal of the Korean Wood Science and Technology
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• 제24권3호
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• pp.12-17
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• 1996

This study was carried out to investigate some mechanical properties for wood rational utilization of heartwood and sapwood in radiata pine according to basic density, ring width and proportion of latewood which were grown in New Zealand. This result were summarized as follow: Heartwood showed 35.78(MPa) of the compression strength parallel to the grain while sapwood showed 42.08(MPa). The modulus of rupture in static bending was higher in sapwood showing 86.12(MPa) than in heartwood 72.99(MPa) Heartwood had 7.38(GPa) for the modulus of elasticity in static bending and sapwood 8.17(GPa). As the basic density and proportion of latewood increased: compression strength parallel to the grain, MOR and MOE in static bending had a tendency to increase. As ring width increased, the mechanical properties decreased.

• 한국가구학회지
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• 제21권6호
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• pp.479-485
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• 2010

제주도 산지림 및 방풍림 삼나무 목재의 조직 특성, 생재함수율, 무기 함유물 농도 및 흑심재 발생률 조사를 통해 얻어진 결과는 다음과 같았다. 1. 흑심재의 발생률은 산지림의 나무에 비해 방풍림의 것에서 훨씬 더 높게 나타났다. 2. 생재함수율은 심재의 재색이 적갈색에서 흑색으로 변함에 따라 높아지는 것으로 드러났다. 3. 흑심재의 방사조직 내에 존재하는 무기 함유물인 $K_2O$와 CaO는 흑심재의 주요 형성 원인 가운데 하나인 것으로 여겨졌다. 4. 목재의 비중 및 기계적 성질은 제주도의 삼나무가 한반도 남부 지역의 삼나무에 비해 비교적 낮게 나타났지만 제주도 내의 방풍림과 산지림 나무 사이에서는 큰 차이를 보이지 않았다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.84-84
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• 2001

The heartwood of Rhus verniciflua has been known to be effective for lingering intoxication and diabetes mellitus and rheumatoidal arthritis in traditional folk medicine in Korea. We have previously reported that antimutagenic effect of flavonoids derived from the heartwood extract of R. verniciflua, and sulfuretin was the active component. Recently, we have demonstrated that sulfuretin could be an anti-inflammatory principle of the R. verniciflua heartwood partially dependent on cyclooxigenase-inhibitory activity. The present study was undertaken to demonstrate the anti-rheumatoidal arthritis effect of the R. verniciflua heartwood extract, its EtOAc fraction and the main flavonoids, sulfuretin and fustin. All the test samples showed variably significant inhibitory effects on hind paw edema induced by Freund's complete adjuvant reagent (FCA reagent). Sulfuretin treatment with 10 mg/kg (i.p.) for seven days showed the inhibitory effect of 54.2${\pm}$3.0%, Similar trends in RA- and CRP tests, vascular permeability test and trypsin inhibitor test were also found. In addition, no dead mouse was found even when the dose was increased up to 5,000 mg/kg (i.p.). Treatment with 250-1,500 mg/kg on normal rats did not show any marked toxicological significances in the tests of body weight gain, wet weight of organs and hepatic functions. These results suggested that the heartwood of R. verniciflua could be an adequate crude drug for rheumatoidal arthritis with an active component of sulfuretin. The toxicological safety of the heartwood of R, verniciflua is contrasted to known severe allergenic action of the stem bark or its exudate.

• 약학회지
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• 제43권5호
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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.

• Journal of the Korean Wood Science and Technology
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• 제34권2호
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• pp.68-77
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• 2006

The heartwood of cengal (Neobalanocarpus heimii) is known to have a high degree of decay resistance by virtue of its high extractive content. After 30 years in ground contact an utility pole of this tropical hardwood was found to be degraded only in the surface layers by cavity-forming soft rot fungi. The present work was undertaken 1) to characterize the degradation of cengal heartwood from the aspect of ultrastructure and chemistry and 2) to investigate the correlation between soft rot decay and its extractive microdistribution in wood tissues. The chemical analysis of cengal heartwood revealed the presence of a high amount of extractives as well as lignin. The wood contained a relatively high amount of condensed lignin and the guaiacyl units. Microscopic observations revealed that vessels, fibers and parenchyma cells (both ray and axial parenchyma) all contained extractives in their lumina, but in variable amounts. The lumina of fibers and most axial parenchyma were completely or almost completely filled with the extractives. TEM micrographs showed that cell walls were also impregnated with extractives and that pit membranes connecting parenchyma cells were well coated and impregnated with extractives. However, fungal hyphae were present in the extractive masses localized in cell lumina, and indications were that the extractives did not completely inhibit fungal growth. The extent of cell wall degradation varied with tissue types. The fibers appeared to be more susceptible to decay than vessels and parenchyma. Middle lamella was the only cell wall region which remained intact in all cell types which were severely degraded. The microscopic observations suggested a close correlation between extractive microdistribution and the pattern and extent of cell wall degradation. In addition to the toxicity to fungi, the physical constraint of the extractive material present in cengal heartwood cells is likely to have a profound effect on the growth and path of invasion of colonizing fungi, thus conferring protection to wood by restricting fungal entry into cell walls. The presence of relatively high amount of condensed lignin is also likely to be a factor in the resistance of cengal heartwood to soft rot decay.

• Journal of the Korean Wood Science and Technology
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• 제10권3호
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• pp.133-134
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• 1982

This experiment has been made to investigate the absorption of watersoluble zinc chloride by Pinus densiflora S. et Z. at different moisture content, under soaking process, to decide the optimum content condition for the maximum absorption of zinc chloride by the wood tested and to investigate the concentration of zinc chloride affecting each moisture content of wood. Material was cut in the Dept. of Forest, College of Agr. S.N.U. Suwon, Korea. Sample was divided into sap and heartwood group and cut $2{\times}2{\times}2\;cm$ in size, having exact three dimensions, using the part of D.B.H. The numbers of sample were 20 pieces for each moisture content condition for both sap and heartwood. Especially, the samples were protected from exposure to keep moisture content in green condition. The ranges of moisture content tested were as the table 3 and 4. The conclusions were as follows: 1. With 3% zinc chloride solution, the rate of absorption decreased with the time increased, if the air seasoned Korean red pine (Pinus densiflora S. et Z.) was treated in steeping process. Initial absorption for 30 minutes was more than 50% of total absorpon for 24 hours. 2. Rate of absorption was same under the green condition, while rate of absorption under the moisture content 7 to 30% varied. 3. Although it was not quite proportional change in the absorption with the difference of moisture content, the great change in the absorption occured by seasoning. With exception sap green condition, sapwood twice more permeable than the heartwood in the oven dried condition and it has been observed the nearly same amount of absorption at the moisture content of 7%, 10% and 15% respectively in heartwood. 4. It was better from water in wood from view-point of absorption of zinc chloride solution, but it was difficult practically to obtain the smallest moisture content, and then it was decided that values of allowable moisture content, on the basis of mean absorption, were 15% to 20% in the sapwood, and in the heartwood, 10% to 15%. The mean absorption for each moisture content in the sap and the heartwood were as following. 5. In general, the concentration of zinc chloride after steeping was nearly same between moisture content and sap and heartwood respectively.

• 한국염색가공학회지
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• 제25권3호
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• pp.194-205
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• 2013

In this study, we report dyeing properties and functionality of cotton and silk fabrics dyed with methanol extract from Juniperus chinensis heartwood. Non-aqueous dye of Juniperus chinensis heartwood extracted with methanol was expressed reddish color. It showed relatively good affinity to silk than cotton. Dye uptake of cotton and silk continued to increase according to the increase of the dye concentration. Cotton was not affected by the dyeing temperature and time, however, dye uptake of silk was increased as the dyeing time and temperature were increased. Dye uptake of cotton and silk were the highest at pH 8 and pH 6 respectively. Dyed fabrics showed various colors depending on mordant types and mordant concentration. Washing, light and perspiration fastness were not good. However, rubbing and dry cleaning fastness showed relatively good grade. Dyed fabrics of ultraviolet-cut ability and deodorant ability were improved. Also, dyed fabrics showed very good antimicrobial abilities of 99.9%.

• 한국염색가공학회지
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• 제25권3호
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• pp.181-193
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• 2013

The purpose of this study is to investigate dyeing properties and functionality of cotton and silk fabrics dyed with hot-water extract from Juniperus chinensis heartwood. Water-soluble dye of Juniperus chinensis heartwood extracted with distilled water was expressed YR color series. Dye uptake of cotton continued to increase according to the increase of the dye concentration. Its variation trends were shown to be similar to the isothermal absorption curve of the Freundlich. Dye uptake of silk was better than cotton, increased depending on increasing concentration of the dye, dyeing time and temperature. Its variation trends were shown to be similar to the isothermal absorption curve of the Langmuir. As the pH increased, the dye uptake of fabrics reduced and showed increased on red tinge. Colors of the dyed fabrics were various, depending on dye concentration and the mordant type and mordant concentration. Washing fastness, light fastness and perspiration fastness were not good. However, rubbing and dry cleaning fastness showed relatively good grade. Dyed fabrics of ultraviolet-cut ability and deodorant ability were improved. And dyed fabrics showed antimicrobial abilities of 99.9% against Staphylococcus aureus.

• Journal of the Korean Wood Science and Technology
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• 제45권6호
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• pp.753-761
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• 2017

The heartwood (HW) of Japanese cedar (Cryptomeria japonica) has usually a reddish color. But some trees have black-colored heartwood (BHW). BHW of Japanese cedar has a low commercial value because of the appearance. Therefore, in this study, a comparative analysis was conducted to evaluate the differences in the physical, mechanical, and inorganic element properties, and decay resistance of red-colored heartwood tree (RHW) and BHW. The physical properties showed significant difference between sapwood (SW) and HW, but there was no significant difference between RHW and BHW. From the results of mechanical properties, no significant difference was recognized in SW of RHW, HW of RHW, SW of BHW, and HW of BHW. There were decay resistance differences between RHW and BHW in HW, and between HW and SW in both RHW and BHW, respectively. The magnesium (Mg), potassium (K), and calcium (Ca) contents had significant differences between SW and HW in both RHW and BHW. In this present study, the decay resistances and the contents of Mg and K were higher in HW than in SW both for RHW and BHW, while these measurements were lower in RHW than in BHW. Therefore, BHW was considered to be worthy as a high-quality material as RHW.

• 임산에너지
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• 제22권1호
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• pp.1-7
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• 2003

우리나라의 주요 조림수종으로 앞으로 대경재로 대량벌목 이용될 낙엽송의 가공와 이용을 위한 기초적 자료인 생재함수율, 비중 및 수축율의 수간내의 변동을 심ㆍ변재로 나누어 조사, 검토하였다. 심ㆍ변재간 생재함수율, 비중 및 수축율은 유의차를 보였다. 생재함수율의 방사방향 분포는 심재에서는 거의 일정한 함수율을 보이다가 변재에서 높아지는 현상을 보였고, 지상고 분포는 심재에서는 높아짐에 따라 함수율이 작아지고, 변재에서는 커지는 것으로 나타났다. 방향에 따른 비중의 차는 심ㆍ변재 모두 없었으며, 지상고에 따라서는 변재는 없었으나 심재에서는 차이를 나타냈다. 방향 및 지상고에 따른 수축율의 차는 대부분 심ㆍ변재에서 별다른 유의차가 관찰되지 않았으나, 변재 일부방향에서 북쪽방향의 수축율이 남쪽방향의 수축율보다 높은 것으로 나타났다.