• Journal of the Korean Wood Science and Technology
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• v.14 no.2
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• pp.36-42
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• 1986

Both the control and heated specimen of oak, hornbean, alder, poplar, red pine and pitch pine among domestic commercial species and taun imported were used for radial and tangential shrinkage and movement that occurred on changing the relative humidity of the atmosphere from 90 percent to 60 percent at $25^{\circ}C$. The results of this study were as follows. 1. The radial and tangential shrinkage of the control and heated hornbean and oak wood, except alder, of high specific gravity showed greater than species with low specific gravity. The ratio of tangential to radial shrinkage was 1.46 for taun to 2.70 for alder. Green volume specific gravity of the heated and soaked specimen of all species except poplar decreased 1.5 to 3.1 percent. Shrinkage of the heated specimen increased more than that of the control specimen, and antishrink efficiency of all timbers except alder had negative value. Shrinkage from green to air dry of treated specimens increased more than case of total shrinkage, and radial shrinkage of those specimen increased greater than tangential shrinkage. 3. The movement of the heating specimen for 120 hours decreased than those of the control and the heating specimen for 240 hours. The movement of heating oak, poplar, red pine and pitch pine (or 240 hours increased rather than those of the control specimen.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.1
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• pp.113-119
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• 2009

The feasibility of using cork oak bark for phosphorus removal from wastewater was evaluated in this study. Recently, development of more cost-effective media while maintaining high efficiency in pollutants removal has received concern. Barks have a negative surface charge and, hence, tend to show a high affinity to bind cations, and they need to undergo chemical modification to increase their adsorption capacity of anions. Bark was hydrolyzed by HCl solution and it received modification using an aqueous solution of high molecular weight polyethylenimine(PEI). Surface modification with HCl and PEI resulted in a decrease of specific surface area of the bark from $1.932 m^2/g$ to $1.094 m^2/g$. The adsorption experiments were carried out in batch tests and the data were fitted to the Langmuir isotherm and Freundlich isotherm equations. Phosphate removal rate was higher at the lower solution pH possibly due to the form of phosphate ion in solution. For the initial phosphate concentration of 10 mg/L, maximum adsorption was 20.88 mg P/g at pH 3 and 12.02 mg P/g at pH 5. Mechanism of phosphorus sorption onto the HCl-PEI bark was examined through FT-IR spectrometer. Ion exchange between $NH^+$ and $H_2PO_4{^-}$ appeared to be a key mechanism of phosphate adsorption onto the HCl-PEI bark surface.

• Journal of the Korean Wood Science and Technology
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• v.22 no.3
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• pp.26-31
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• 1994

To provide further information for reutilization of the waste wood obtained after cultivating oak mushroom in Kangwon-do, the crystal structures of the waste wood were investigated and compared to those of normal woods by a series of x-ray diffraction analysis. The results obtained are as follows: 1. An x-ray diffraction diagram of cultivated wood for 5 years was same as that of typical cellulose with some orientation of cellulose crystallites, but that of cultivated wood for 8 years a random. 2. Crystallinity indices in normal and cultivated woods for 5 years ranged from 57% to 60%. In the cultivated wood for 8 years, however, the value showed about 40%. 3. Crystallite widths of cultivated woods for 5 years and for 8 years were 3 nm and 2.5 nm, respectively. 4. Intensity ratios of equatorial and meridional layers did not show any significant differences. From the above results, it is clear that the waste wood obtained after cultivating oak mush room for 5 years showed basically same crystal structures with normal wood. Therefore, we think that the waste wood may be used available for cellulosic material instead of normal wood.

• Journal of Ecology and Environment
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• v.35 no.3
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• pp.227-234
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• 2012

Quercus aliena and Q. serrata are both occur as natural vegetation alongside natural freshwater bodies of the southern Korea Peninsula. Q. serrata dominates over Q. aliena as secondary forest vegetation in the present day. In order to explain these natural distributional traits of the oak species, we conducted some experiments with oak seedlings which treated with major important environmental resources, including light, moisture and nutrients, under controlled conditions. We then measured the ecological niche breadths and overlap from 15 eco-morphological characteristics. The ecological niche breadth of Q. aliena and Q. serrata were higher in terms of the nutrient factor applied, but was lower terms of light. The niche breadth of Q. serrata was wider than that of Q. aliena in light and moisture exposure. On the other hand, the niche breadth of Q. aliena was similar with that of Q. serrata in terms of the nutrient factor applied. These results imply that Q. serrata has a broader ecological distribution in over a wider variety of light and moisture environments than that of Q. alien. Ecological niche overlap between two oak species was the widest in terms of the light treatment factor applied, and narrowest in terms of moisture. This response pattern was also verified by cluster and principle component analysis. These results suggest competitive interactions between Q. serrata and Q. aliena seedlings may be higher for light resources than moisture or nutrient resources, and that Q. serrata is more shade tolerant than Q. aliena.

• Journal of Forest and Environmental Science
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• v.30 no.3
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• pp.267-276
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• 2014

Collection of lichen together with tree twigs of oak and other trees bearing abundant growth of lichens is a common practice among the villagers and the rivals residing near Oak forests in Kumaun Himalaya. Nainital forest division represents about Twenty nine percent vegetation of the Oak forest in Kumaun Himalaya. In Kumaun, the lichen trade share is decreasing at an alarming rate of 21.93% which requires immediate actions by the Government. Lichen contributed significantly to household earnings with off-farm activities and this sector was found second highest income creator after Agriculture. It is a source of cash income during the season of extraction, which increases economic access to food. It has been observed in the present study that the secondary collector and transporters together get maximum share (>50%) of income generated from lichen, thus economic exploitation of the poorly educated people by the traders was still prevalent in the area. To improve the socio-economic standard of the people of Kumaun, it may is necessary to increase and improve the lichens resources of the area. There is a strong need for scientific management, best harvesting practices and strict monitoring of resources. The present study was conducted to assess the present and future resource potential for the conservation and sustainable management of lichens, existing market mechanism, role of Lichens in economic upliftment and livelihood generation of rural communities in Kumaun Himalaya.

• The Korean Journal of Mycology
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• v.28 no.1
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• pp.38-40
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• 2000

Anamorph and teleomorph of Diatrype stigma on the bed-log inoculated with oak-mushroom (Lentinula edodes) in Korea were observed and identified. As the characters of anamorph of Diatrype stigma, conidia were hyaline, falcate or slightly curve, and $1{\sim}1.5{\times}12.5{\sim}17.5\;{\mu}m$, and conidia layer was confirmed under the bark. About teleomorph, perithecia $150{\sim}200{\times}450{\sim}500\;{\mu}m$, with ostiole ($30{\sim}40\;{\mu}m$, three- to four-sulcate). Size of ascus containing 8 ascospores was $5{\sim}6{\times}30{\sim}40\;{\mu}m$. Ascospores were hyaline to pale brown, $1.5{\sim}2{\times}5{\sim}7.5\;{\mu}m$ and mostly biguttulate.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.11a
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• pp.55-64
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• 1996

mouse chromesome2에 있는 agouti locus는 정상적으로는 털색깔을 조절하는 gene이다. mouse agouti gene은 최근에 cloning 되었고 131 amino acid peptide와 consensus signal peptide를 encode한다고 보고되었다. 이 논문에서 interspecies-DNA hybridization approach를 이용하여 mouse agouti gene의 human homologue를 cloning 하였다. Sequence analysis 결과, 이는 mouse gene에 85% 유사하였고 consensus signal peptide sequence 를 포함하는 132 amino acid를 coding하였다. somatic-cell hybrid mapping pannel과 Fluorescence-in-situ hybridization에 의한 chromosomal mapping을 한 결과, agouti gene은 MODY (maturity onset diabetes of the young), myeloid leukemia locus 등이 위치한 human chromosome 20q 11.2에 mapping 되었다. 성인 tissue로부터 추출한 RNA를 이용한 발현연구에 의하면 human agouti gene은 adipose tissue와 teatis에 발현되었다.

• Journal of the Korean Wood Science and Technology
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• v.18 no.4
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• pp.41-52
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• 1990

Experimental external collector type solar lumber dryer with $1.6m^2$ of collector area and $1.0m^3$ of maximum dryer capacity was designed and constructed to investigate the conditions inside and outside the dryer and collector. The efficiency of collector was calculated and numbers of drying-days and collector areas required to dry $0.2m^3$ and $1.0m^3$ of pine and oak at various an flow rate inside collector were estimated for eight cities in Korea. Average temperatures of collector-inlet and -outlet air and heat absorber were $52.5^{\circ}C$ $57.9^{\circ}C$, and $71.1^{\circ}C$. respectively at 4m/sec of an flow rate inside collector on sunny day in summer. Overall heat transfer coefficient of collector was 4.875W/$m^2^{\circ}C $ and collector efficiency was 52%. Estimated numbers of drying-days required to dry $0.2m^3$ of pine and oak from 80% to 15% moisture content at various air flow rate inside collector were 38 and 66 days. respectively. Areas of collector required to dry $1.0m^3$ of lumber at desired safe drying rate were estimated as $13.7m^2$ for pine and $16.0m^2$ for oak.

• Journal of the Korean Wood Science and Technology
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• v.26 no.1
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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.

• Journal of the Korean Wood Science and Technology
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• v.24 no.2
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• pp.20-25
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• 1996

Wood chips of oak(Quercus mongolica) and larch(Larix leptolepis) were exploded with the optimum condition. Main components of exploded wood were separated with hot hot water and methanol. The hemicelluloses were purified from hot water extracts and alditol complexs were prepared from purified hemicellulose. And also, cellulose nitrate was prepared from extractive residue and characterized. The results can be summarized as follows. 1. Amounts of carbohydrate(72~79%) in the crude hemicellulose of larch wood was more than those of oak wood(55~66%). 2. The crude hemicelluloses were mainly composed of oligosaccharides in oak wood but those in larch wood contained about 50% monosaccharides. 3. Decolorization of hemicellulose was successful with activated charcoal and ion-exchange resin treatment. The alditol yields were 56.3~82.9%. 4. The degree of substitution(D.S.) of cellulose nitrate was 1.95~2.87 and it showed a good acetone solubility.