• Journal of Life Science
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• v.17 no.1 s.81
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• pp.105-109
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• 2007

This study was carried out to investigate the biological effects oak wood vinegar. Antimicrobial activity was tested in five microbial species at the concentration of 5 to $50{\mu}l$ of oak wood vinegar by paper disc method. Growth of P. oleovoranse, P. vulgaris, E. coli, S. aureus and Prevotella intermedia was inhibited at a dose of as low as $50{\mu}l$ of oak wood vinegar. Antioxidant activities were measured by using DPPH radical scavenging and SOD-like activity. DPPH radical scavenging and SOD-like activities were 90% and 65% at the concentration of $25{\mu}l\;and\;50{\mu}l$ of oak wood vinegar, respectively. Stimulation of the macrophages RAW264.7 cells with lipopolysaccharide (LPS) resulted in increased production of nitric oxide (NO) in the medium. However, the oak wood vinegar showed marked inhibition of NO synthesis in a dose-dependent manner. This result suggest that oak wood vinegar plays significant role for activation of immune system in the pathogenesis of inflammatory diseases.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.127-131
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• 2008

Ambrosia beetle, Platypus koryoensis, is a vector of oak wilt disease caused by Raffaelea sp. in Korea. The degree of damage by oak wilt disease was dependent on the density of the beetles in the oak trunk, a relationship between the degree of damage by oak wilt disease and the density of beetle on the basis of the number of entry hole was studied. Entry hole distribution within tree trunk was analyzed by the nearest neighbor method. Thirty four oak trees (Quercus mongolica) located in survey area were selected and then degree of damage, the number of attack hole/$623cm^2$ in upper (50cm from the surface) and lower (surface) trunk and the nearest neighbor distance between the holes were measured. The number of hole and the nearest neighbor distance in upper and lower part were positively correlated with each other. As the degree of damage was severer, the number of the holes increased, whereas the nearest neighbor distance decreased. The distribution pattern of the hole was changed from clumped one to uniform as the severity of damage increased. These results suggested that Platypus koryoensis attacked the oak tree in concentrative manner at initial stage of attack but at final stage, it distributed uniformly to reduce intraspecific competition between the beetles.

• Journal of Climate Change Research
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• v.4 no.1
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• pp.41-49
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• 2013

Recent findings have revealed that black carbon is one of the substantial materials affecting climate change along with greenhouse gases. Usually, black carbon is generated by incomplete combustion of biomass and deposited on snow and ice surface, resulting in increasing adsorption of radiant energy and accelerating ice melting. However, it is still questionable what the emission characteristics of black carbons from biomass combustion is. We investigated the emission characteristics of black carbon generated from a wood stove in this study. We found that the emission of black carbon was highly dependent upon combustion temperature and the amount of combustion air supplied. The emission factors were 1.01 g-BC/kg-Oak for fireplace wood burning under incomplete combustion, 0.37 g-BC/kg-Oak for fireplace wood burning under complete combustion and 0.29 g-BC/kg-Oak for small wood-stove burning.

• Journal of the Korean Wood Science and Technology
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• v.46 no.2
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• pp.178-188
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• 2018

The aim of this study was to assess the in vitro potential of water extract from torrefied oak wood as a natural antioxidant. The antioxidant potential of the extracts was assessed by employing different in vitro assays, including reducing power, DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)], and FRAP (ferric reducing antioxidant potential) assays. The DPPH activity of the extract was increased in a dose-dependent manner. Measurement of total flavonoid content of water extract from torrefied oak wood was achieved using an aluminum chloride colorimetric assay; the extract contained 192.12 mg/g flavonoid, which was significantly high when compared with standard quercetin. The results obtained in this study indicate that water extract from torrefied oak wood has significant potential for use as a natural antioxidant agent.

• Journal of the Korean Wood Science and Technology
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• v.2 no.1
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• pp.3-18
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• 1974

The exports of plywood are increasing annually and it has ranked first in the world market because of the high quality product and manufactured using mordern techniques. However, it is known that the exports of the other wood products, except plywood, is inactive because of their low quality. Accordingly, to increase the exports of various wood products investigations were carried out on kiln drying techniques to improve the quality of the wood. Wet wood should be kiln dried before use to prevent various drying defects such as distortion, shrinkage etc., which would develop after processing,:and also wet wood is not suitable for cutting, gluing and finishing. Therefore, the kiln drying properties of lumber from such species as oak, ramin and meranti which are used in large quantity for manufacturing exporting wood products have been studied. The results of the research are summarized as follows. (1) The end checks and the time for drying from initial moisture content of about 40 percent to 5 percent moisture content in ovendry were investigated as follows: (2) The kiln dried results, for 30mm stock, which are presented by using kiln schedule table 3 are as follows: (3) The kiln schedules for ramin, meranti and oak are given respectively as follows: Ramin kiln schedule: Table 17 and Table 18. Meranti schedule : Table 12. Oak schedule : Table 15.

• Analytical Science and Technology
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• v.11 no.4
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• pp.254-259
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• 1998

The adsorption and reduction characteristics of chromium(VI) by oak sawdust were studied. The optimum adsorption condition is obtained from the measurement of the distribution coefficient($K_d$) and adsorption capacity of Cr(VI) on the sawdust by changing pH of the solution. As a result, it was found that pH 2.0 was optimum because $K_d$ of Cr(VI) was maximum and reducing quantity was minimum. By the use of these characteristics of the oak sawdust, the removing of Cr(VI) in industrial waste water was examined.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2003.07a
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• pp.81-81
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• 2003

우리 민속전통주의 참나무 oak통을 이용한 저장주의 가능성을 규명하기 위하여 상법에 의하여 쌀로 제조한 증류주를 용량 10L의 수입 참나무(oak)통에서 실온 25로 5개월부터 9개월까지 숙성한 숙성주와 숙성하지 않은 증류주의 성분함량 변화를 측정하여 다음과 같은 결론을 얻었다. 1) 유기산은 검출되지 않았으며 다만 7개월 이상 숙성주에서 acetic acid 가 0.023 ∼ 0.033%로 미량 검출되었다. 2) 총 유리아미노산의 함량은 숙성 기간이 경과할수록 감소하였다. ) 휴젤유 함량을 측정한 결과 숙성 기간이 길수록 감소하였으며 휴젤유 중 가장 많은 성분은 isopropyl alcohol이었다. 4)휘발성 향기성분은 숙성기간이 경과함에 따라 이취를 생성할 수 있는 aldehyde나 ketone류가 감소하였고 신선한 과실향이나 꽃향기 등의 향기 성분인 ester류가 증가하여 숙성 5개월째에는 oak 숙성주로서 가장 독특한 향을 갖는다고 예측할 수 있었다. 5) Gas chromatography-olfactometry를 이용하여 각각의 시료들의 향기특성을 관능 평가하여 동정한 결과 전반적으로 green 및 herb note가 우세한 숙성기간 8개월 숙성주가 가장 우수한 것으로 판단되었다. 6) 전체적인 색상 비교 결과 기준값이 되는 oak 숙성을 하지 않은 증류주보다 숙성기간이 오래 경과된 숙성주일수록 점점 높아지는 경향을 보였다. 또한 UCS graph에서 보면 기준값 보다 숙성된 시료가 탁하다는 것을 나타냈고 색상 선에서는 기준시료보다 R(red)에 가까웠다. 숙성기간이 긴 발효주일수록 명도는 낮았다.

• Journal of the Korean Wood Science and Technology
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• v.20 no.3
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• pp.11-20
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• 1992

Steam explosion is one of the most effective pretreatment for fractionating wood. This leads to the total utilization of wood basic components; cellulose, hemicellulose and lignin. The amount of sugar and lignin extracted with the hot water method was very low. The lignin content of residues after extraction with using a sodium hydroxide treatment, increased delignification of carbohydrate as the concentration of alkali was increased. Oak, pretreated with steam exploded at 25kg/$cm^2$ for 6 min. then 1% alkali for 2hrs. showed a delignification rate up to 95%. A sodium chlorite treatment of steam exploded pine and oak also afforded a high deligninfication effect. Pine, treated 10% sodium chlorite for 2hrs. showed high delignification. However, by using a sodium hydroxide treatment, a 2% retreatment for Ihr. after a 2% for 2hrs. afforded remarkable delignification effect on exploded wood at 30kg/$cm^2$ for 9min. and at 35kg/$cm^2$ for 3-6min. In oak, an initial 2hrs. treatment of 2% sodium chlorite was followed by a second 2hrs. treatment at 10%. This showed a delignification rate of 96%.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.1
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• pp.75-78
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• 2003

This study was carried out to investigate the mineral content of the feces of the $5^th$ instar larvae in a few silkworm species such as a parent domestic silkworm (Jam134), a hybrid (Kumok-jam), the Japanese oak silkworm, and the Chinese oak silkworm. The major minerals of all silkworms throughout all $5^th$ instar larval period are K, P, Mg and Ca, and the result is consistent with the previous study of the mineral content in the mulberry leaves. Although the calcium content decreased sharply at $7^th$ day of the $5^th$ instar, the crude protein content significantly increased at the same age in both domestic silkworms, suggesting a direct relationship between feeding behavior of the silkworms at the larval period and mineral/protein contents. However, this trend was not observed in both oak silkworms. In the comparison of the mineral content among silkworm species, two domestic silkworms were significantly higher in the calcium content compared with two oak silkworms, and the hybrid Kumok-jam was further higher significantly than the feces of parental Jam 143. Excluding the calcium content, overall no significant content variation in other minerals was observed among four silkworm species studied in this study.

• Journal of Environmental Science International
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• v.20 no.2
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• pp.215-222
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• 2011

The adsorption behavior of nitrate nitrogen was investigated from aqueous solution using char prepared from oak chip. The removal rate of nitrate nitrogen was found to be dependent on temperature and it is increased as the temperature increase. Adsorption equilibrium data of nitrate nitrogen on oak char. reasonably fitted Langmuir and Freundlich isotherm models. The adsorption energy obtained from D-R model was 12.5 kJ/mole at $20^{\circ}C$ indicating an ion exchange process as primary adsorption mechanism. Thermodynamic parameters such as ${\Delta}G^o$, ${\Delta}H^o$, and ${\Delta}S^o$ were -23.76 kJ/mole, 26.1 kJ/mole and 89.7 J/K mole at $20^{\circ}C$, respectively, indicated that the nature of nitrate nitrogen adsorption is spontaneous and endothermic.