• Journal of the Korea Furniture Society
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• v.18 no.2
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• pp.106-110
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• 2007

This study was performed to find potentialities of the leaves of gingko tree (Gingko biloba L.) as a raw material for particleboard (PB) manufacturing. Various amounts of the leaves were mixed with wasted wood particles to manufacture PB. Physical and mechanical properties, such as density, internal bond (IB) strength, and modulus of rupture (MOR) of manufactured PB were not much different from those of the control board. Formaldehyde emission values decreased with increasing the amount of leaves. Especially, the formaldehyde emission of PB made with 5 percent of leaves was decreased to 1.31 mg/l, which is about 36% lower emission than that of the control. From these results, the leaves of gingko tree may be considered as an additive of lowering formaldehyde emission in a functional PB manufacturing process.

• Journal of Korea Foresty Energy
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• v.25 no.2
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• pp.28-33
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• 2006

This study was conducted to find potentialities of the leaves of gingko tree (Gingko biloba L.) which has been planted as a roadside tree in Korea because of its resistance on air pollution, insect, fungi, etc. Various amounts of the leaves were mixed with wasted wood particles to manufacture particleboard. Their influences on physical and mechanical properties and the formaldehyde emission of PB were investigated. Physical and mechanical properties, such as density, modulus of rupture (MOR), and internal bond (IB) strength, of manufactured particleboard were not much different from those of control board. Formaldehyde emission values were decreased with increasing amount of leaves in PB prepared. Especially, particleboard made with 3 percent of leaves was decreased to $1.66mg/{\ell}$ in formaldehyde emission, which is about 40% lower emission than that of control. From these results, the leaves of gingko tree may be considered as a formaldehyde emission lowering additive in a functional PB manufacturing process.

• Korean Journal of Veterinary Research
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• v.31 no.3
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• pp.319-327
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• 1991

Gingko biloba is one of the oldest trees on earth. It can be traced 300 million years or more into past. In recent years, this tree has become increasingly popular because of its longevity. Amount of comsumption of Gingko leaves in Korea is increased to produce drugs for blood circulating system's disorder. The workers who work at the company of product drug with Gingko leaves complain pruritus at belt position of west, however toxic substance from extracts of Gingko biloba was carried out to determine what kind of the toxic substance from extract could induce a contact dermatitis by means of histopathological study. Dried leaves of Korean G. biloba were exhaustively extracted with chloroform. The aqueous chloroform residue was extracted with hexane. After evaporation, the hexane extract was passed through a silica gel column chromatography, it was separated into 9 fractions by means of gradient solvent (benzene: acetone/ 98~93 : 2~7%). The 4th and 7th fraction were idendified as bilibol and gingkolic acid by silica gel thin layer chromatography and NMR spectrophotometer. The 4th and 7th fractions of Korean Gingko leaves have an irritant substances which can be induced ear swelling and increased thickness of stratum cornium of rabbit ear exposed with the fractions (3 time/3 day, $100{\mu}l$ of 50mg/ml ethyl alcohol). In the 4th fraction, the substance have induced the surface of ear to swell and mass of unknown cell like inflammatory cell were infiltrated within the stratum corneum, and the 7th fraction have the surface of ear to loss the hairs, and sebaceous gland and follicle of hair were infiltrated with inflammatory cells. and other fractions at all did not induced a certain contact dermatitis and also Deutschen drug of Gingko (named as Gerigeron) have induced the contact dermatitis such as dematitis of Korean Gingko extract.

• Journal of environmental and Sanitary engineering
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• v.1 no.1 s.1
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• pp.97-107
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• 1986

This study was performed to investigate the air pollution tolerance of urban trees; Gingko biloba, Platanus occidentalis, Salix pseudolagiogyne and Purunus serrulata growing in Seoul, Taegu, Chungju area. Vitality of trees and water soluble sulfur content in the leaves were determined at 24 points in those cities. The ratio of the each number of Platanus occidentalis, Gingko biloba, Salix psuedolagiogyne and Prunus serrulata to the total number of urban tree in Seoul area was $49.38\%,\; 17.36\%,\; 13.42\%,\;2.43\%$, respectively. Its ratio in Taegu area was $36.76\%,\;14.25\%,\;13.36\%,\;3.32\%$ and in the Chungju area was $59.06\%,\;17.35\%,\;11.09\%,\;8.33\%$, respectively. The species deversity was 0.7017, 09067, 0.5297 in Seoul, Taegu, Chungju, respectively. The significant correlation between the S02 concentration and the tree vitality highly found on Platanus occidentalis, Gingko biloba, Salix pseudolagiogyne and Prunus serrulata. Positive correlation coefficient between $SO_2$ concentration and water soluble sulfur content were shown on Platanus occidentalis, Salix pseudolagiogyne and Prunus serrulata and that between tree vitality and water soluble sulfur content were shown on Platanus occidentalis and Gingko biloba. The tolerant to the S02 gas was high in order of Salix pseudolagiogyne, Gingko biloba, Prunus serrulata and Platanus occidentalis. Also the absorption activity to the $SO_2$ gas was high in order of Salix psuedolagiogyne, Gingko biloba, Platanus occidentalis and Prunus serrulata.