• Journal of the Korean Wood Science and Technology
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• 제38권4호
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• pp.349-358
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• 2010

본 연구는 경상남도 함양군 지리산의 고로쇠나무 수액의 출수와 영향 인자들을 분석하여 최적의 출수 조건을 얻는데 기여하고자, 출수량과 시험지의 기온 및 상대습도, 흉고직경 그리고 수액내 당 함량 사이의 상관성을 분석하였다. 고로쇠나무의 흉고직경에 비례하는 출수량과의 상관성은 출수량이 많은 날에 높았고 출수 일수와 시기는 공시목 사이에 큰 차이점이 없었다. 출수량이 높았던 날들의 기온은 일평균기온 $1.2{\pm}1.6^{\circ}C$, 일최저기온 $-4.3{\pm}1.5^{\circ}C$ 그리고 일최고기온 $11.8{\pm}1.9^{\circ}C$로 나타났다. 수액 출수는 기온이 영하의 온도를 지속하거나 영상의 온도를 지속할 경우에는 관찰되지 아니하였다. 기온과 출수량과의 상관 분석에서 일최고기온과 일평균기온이 유의적(p < 0.05)으로 관련성이 있는 것으로 나타났다. 수액의 출수 기간 동안 자당의 농도는 일정 수준을 유지 하였으나 출수가 종료되는 시점에서 급격하게 감소하였다.

• 한국가구학회지
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• 제18권2호
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• pp.143-146
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• 2007

This study was carried out to assess the dimensional stability of wood material treated by plastic processing for bentwood and compression wood. The evaluation method was different between two wood materials, but the treatments for them were very similar to each other. One of the main methods is heat treatment with sufficient water vapor. In bentwood, the used species were painted maple (Acer mono), bitter wood (Picrasma quassioides) and birch (Betula schmidtii). Steaming was the worst treatment method for dimensional stabilization of bentwood. The best results could be attained with PEG treatment for dimensional stabilization of bentwood. Dimensional stability of bitter wood was found to be conspicuous. However the steaming treatment at lower temperatures, i.e., about $130^{\circ}C$ was not suitable for dimensional stability of bentwood. In compression wood, the used specimen was Italian poplar wood (Populus euramericana). Two heat compressive pressing conditions, an open-press system and an air-tighten closed-press system, were used. The recovery rate was measured after boiling and/or absorbing in water to estimate the dimensional stability of heat compressed wood. The best dimensional stability of compressed wood in the air-tighten closed-press system was found to be better at $200^{\circ}C$ than $180^{\circ}C$. The best compression rate for dimensional stability was 73 percent.

• Journal of the Korean Wood Science and Technology
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• 제26권1호
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• pp.38-50
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• 1998

Laser cutting tests were conducted to investigate the laser cutting characteristics of solid woods such as 25mm-thick white oak(Quercus acutissima) and maple(Acer mono), and wood-based panels such as 15mm-thick medium density fiberboard and particleboard. Test variables were laser power, cutting speed, grain direction, and moisture content. Specific cutting energy was measured and the qualities of cut surface were estimated in constant laser power. Specific cutting energy of white oak was larger than that of maple, and specific cutting energy of medium density fiberboard was smaller than that of particleboard. For both white oak and maple, specific cutting energy of green wood was smaller than that of air-dried wood because weight loss of moisture evaporation in green wood was larger than that in air-dried wood. In laser-cut surface, wood cells were not deformed and damaged, but in circular saw-cut surface fibers were pushed out and cut, and wood cells were deformed severely. However, mechanical surface roughness of saw-cut surface was smoother than that of laser-cut surface because of the existence of undeformed cell cavity in laser-cut surface.

• 한국산림과학회지
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• 제65권1호
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• pp.60-67
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• 1984

한국산(韓國産) 단풍나무속(屬) 6개(個) 수종(樹種)의 심재내(心材內) 지질(脂質)을 추출(抽出)하여 Thin Layer Chromatography에 의한 방법(方法)으로 종(種)을 식별(識別)하였으며, 정색반응(呈色反應)의 특징(特徵)으로 유연관계(類緣關係)를 조사(調査)한 결과(結果)를 요약(要約)하연 다음과 같다. 1) 6개(個) 수종(樹種) 심재(心材)의 지질함량(脂質含量)은 유리암질(遊離暗質)이 평균(平均) 2.85%, 결합지질(結合脂質)이 1.54%이었으며, 전지질(全脂質)은 4.39%이었다. 2) TLC 정색반응(呈色反應) 특징(特徵)에 의해서 단풍나무속(屬) 6개(個) 수종(樹種) ; 신나무, 고로쇠나무, 네군도단풍, 단풍나무, 은단풍, 복자기를 식별(識別)할 수 있었으며, 정색반응(呈色反應)에 의한 유연관계(類緣關係)를 보면 단풍나무와 복자기가 근연(近緣)임을 알 수 있었다.

• Journal of the Korean Wood Science and Technology
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• 제20권4호
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• pp.15-20
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• 1992

This study was carried out to improve the method of tapping sap from Betula platyphylla Sukatschev, Betula costata Trautv., Betula schmidtii Regel, Betula davurica Pallas, Betula ermanii Cham, Acer mono Maxim and Acer pseudo-sieboldianum Kom and to use it to natural drinks. The mal or results are as follows: 1. It is no difference of the amount of sap by tapping methods and species of trees. The larger D.B.H. is, the more amount of sap can be gotten. So we thought that the best tapping method is hole-drilling to prevent trees from damage. 2. Sap contains sugars and mineral materials. Birches have glucose and fructose, much more mineral materials than maples. Sugar of maples is mainly sucrose. 3. We assume that mineral materials of birches are effective to urination, to make a stong dody and sucrose of maples is effective to recover from one's fatigue by controlling the blood sugar. 4. In vacuum packing after sterilizing the sap in low temperature, it could be stored more 1 year. So, it is possible that sap will be commercialized.

• Journal of the Korean Wood Science and Technology
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• 제25권4호
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• pp.75-91
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• 1997

Laser cutting tests were conducted to investigate the laser cutting characteristics of solid woods such as 25mm-thick white oak(Quercus acutissima) and maple(Acer mono), and wood-based panels such as 15mm-thick medium density fiberboard and particleboard. Test variables were laser power, cutting speed, grain direction, and moisture content. Cutting depths, kerf widths and the maximum cutting speed were measured. Cutting depths were increased as focus of laser beam was moving from above the workpiece to on the surface of workpiece, and also to below the workpiece. Kerf widths were decreased as focus of laser beam was moving from above the workpiece to on the surface of workpiece, but were increased as focus of laser beam was moving from on the surface of workpiece to below the workpiece. Minimum kerf widths were obtained when focus of laser beam was positioned on the surface of workpiece. Cutting depths and kerf widths were decreased with increase in moisture content, and cutting depths and kerf widths of more dense white oak were smaller than those of maple. And also cutting depths and kerf widths of particleboard were smaller than those of medium density fiberboard.

• Journal of the Korean Wood Science and Technology
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• 제46권3호
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• pp.270-277
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• 2018

본 연구에서는 기록으로 남아있는 밀성박씨 경주 손곡문중의 박씨문헌록(朴氏文獻錄)과 지당실기(智堂實紀)의 인쇄에 사용된 목판의 수종을 식별하고자 수행되었다. 전체 282장의 목판 중 88장을 무작위로 선정하여 광학현미경으로 목재해부학적 특징을 비교분석한 결과, 7개의 목재수종이 식별되었다. 즉 가장 많이 사용된 수종은 서어나무로 39.8%를 차지하였고, 그 다음으로 돌배나무가 25.0%, 고로쇠나무가 15.9%, 산벚나무가 10.2%, 피나무가 3.4%, 감나무가 3.4%, 그리고 거제수나무가 2.3%가 사용된 것으로 조사되었다. 이 같은 결과는 일반적으로 목판인쇄에 사용된 목재수종의 범주에 속하는 것이다. 또 식별된 모든 수종들은 활엽수 산공재로 복잡한 한자를 새기기 쉽고 여러 번 인쇄를 하더라도 글자가 쉽게 닳지 않고 용이하게 구할 수 있는 목재수종이 사용된 것으로 판단된다.

• Journal of the Korean Wood Science and Technology
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• 제3권1호
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• pp.3-15
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• 1975

How to stabilize wood against shrinking and swelling in variable atmospheric moisture conditions is important to the wood-using industry and a challenge to research. Polyethylene glycol stabilize wood by bulking the fiber. PEG also serve as a chemical seasoning agent, suppress decay in high concentrations, and have slight effect on physical properties, gluing or finishing. The study designed to determine the effect of PEG-400 on the dimensional stabilization of local hardwoods for wood carvings that could supply a greatly expanding tourist trade and making curved furniture parts, lamp stands and other decorative objects, and possible gunstock. The species examined were 6 species, Seo-Namoo (Carpinus laxiflora), Cheungcheung-Namoo (Cornus controversa), Gorosae-Namoo (Acer mono), Karae-Namoo (Juglans mandshurica), Jolcham-Namoo (Quercusserrata) and Sanbud-Namoo (Prunus sargentii), used as block of 5cm thick radially to the grain, 7cm wide tangentially, and 70cm long parallel to the wood grain. All these test piecies were conditioned above the fiber saturation point before impregnation. The stabilization effects were determined for PEG-400 treated woods in a 50 percent solution for 20 days. The following conclusions were obtained. PEG retentions increased with treating time. It was more effective to treat at 60$^{\circ}C$ than at room temperature. In degree of PEG-400 impregnation on species, Cheungcheung-Namoo havinglow specific gravity had the highest retentions, 68.77% but the lowest, 56.33% was shown in Jolcham-Namoo with high specific gravity. Specific gravity of treated wood increased considerably with effectiveness of polymer loading. The increases in specific gravity were 5.36 to 13.16 percent. The highest was Jolcham-Namoo, the lowest Karae-Namoo. On the dimensional stability, a 40 percent of effectiveness of polymer loading was just as effective as 60 percent in reduction in water absorptivity (RWA), antishrinkage efficiency (ASE) and antiswelling efficiency (AE), and from over 60 percent they increased more rapidly. Also species response varied considerably. ASE was 30.12 to 69.97 percent tangentially and 27.86 to 56.37 percent radially, AE 34.06 to 73.76 percent tangentially and 30.11 to 70.12 percent radially, and RWA 42.31 to 65.32 percent. No differences in volume swelling among the 6 species were observed. Its values were ranged from 14.98 to 19.55 percent and also increased with PEG retentions. On the mechanical properties, the strengths very much decreased with PEG-400 loadings as shown in Figure 12; that were 11.41 to 22.90 percent in compression, 21.61 to 34.35 percent in bending and 22.83 to 36.83 percent in tensile strength. PEG retention in cell wall was less than 1 percent and the most of PEG were immersed in cell lumen. Except for Korae-Namoo, effectivenesses of polymer loading were as much high as 61.58 to 75.02 percent. This is believed to be due to the effect of PEG-400 on excellant dimensional stability of treated woods.

• The Korean Journal of Ecology
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• 제3권1_2호
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• pp.17-20
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• 1980

This paper contains the results obtained by ecological investigation of ilora in Muie Island of Incheon Harbor in the xestern coast in Korea. 14 varieties, 1-27 species, 57 families and 142 genera of Tracheophyta were recorded by field investigations conducted over three times in May and July, 1976 and August, 1980. The flora of this island showed a plant community predominated by Pinus densiflol-a grown in miggle with Carpinus laxiflora, Quel-cus serrata and Rhododendron muucronulatum. Generally, the number of plant species was scarce, but it was an unexpected result that such remote mountainous plants as Lysinzachia clethrozdes, Sy7zeilesis palnzata and Lilzunz disttcum etc. were encountered in a wood surrounding Seohwang-dang, the shrine of a tutelary deity, on 126-Meter Hill at the northern end of the island. There also countered in Hoyong mountain valley were deciduous broad-leaved forests without pine tree which mainly consisted of Prunus leveillea7za, Fraxinus rhynchophylla, Platycarya strofilada, Quercus serrata. Quercus acutissznza and Acer mono. In addition, herbaceous plants, such as Syneilesis palmata, Codonopsis lanceolata and Lysi\ulcornerna barystnchy were grown as the undergrowth of these forests. Drosera rotundifolio, an unlooked-for plant, . appeared in the middle of the eastern coast of the island. Camellia japo7tica was grown spontaneously in Deogjeog Island 261cm southwest from the island, while no evergreen broa-leaved tree could be located except 2 species of Vztex rotztndifolia and Euo~zymus japonrca. It may be considered that such simple flora of this island compared with that of land is attributed to the fact that the formation of the former took place in the period far latter than that of the latter.

• Journal of the Korean Wood Science and Technology
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• 제30권2호
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• pp.87-94
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• 2002

본 연구는 고주파 가열에 의한 산벚나무, 소태나무, 서어나무, 굴참나무, 박달나무, 고로쇠나무, 피나무, 소나무, 리기다 소나무, 참오동나무의 휨가공성을 평가해 보기 위하여 실시하였다. 본 연구에서 휨가공을 위한 곡율반경은 휨틀의 곡율반경에 의해 4 cm, 6 cm, 10 cm으로 구분하고, 대철의 두께는 0.6 mm와 0.8 mm로 구분하였다. 본 연구결과 소태나무, 서어나무, 박달나무, 고로쇠나무는 모든 곡율반경에서 100% 성공률을 나타내었다. 산벚나무와 굴참나무의 경우 58%와 83%의 성공률을 각각 나타내었다. 피나무와 오동나무의 경우 총 29%와 8%로 매우 불량하게 나타났고, 곡율반경 4 cm에서는 모두 실패로 나타났다. 침엽수재인 소나무와 리기다 소나무는 각각 44%와 56%의 성공률을 나타내었다. 대철의 두께는 휨가공성의 쉽고 어려움보다는 건조시 건조속도에 더 많은 영향을 주는 것으로 나타났다. 건조과정에서 대철두께가 얇을수록 휨가공부재의 건조 속도가 빠른 경향을 나타내었다.