• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.58-64
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• 2004

For the utilization of chestnut inner bark as forest biomass, the diethyl ether solubles of hot water extract from chestnut inner bark was analyzed by HPLC. Each peak was identified by comparing with retention time of standard regents and their purity from obtained UV spectrum by RI detector. Identified 6 compounds were gallic acid, 3,5-dihydroxybenzoic acid, 2,4,6-trihydroxybenzoic acid and protocatecualdehyde as phenolic acids and aldehyde, and catechin and epicatechin as flavonoids.

• Journal of the Korean Wood Science and Technology
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• v.31 no.4
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• pp.24-30
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• 2003

In order to develop structural 'bamboo zephyr board', properties of boards produced by various methods making zephyr were estimated. All of boards were tested with KS(Korean Standards) F 3014 Particle board, and results were summarized as follow. The zephyr boards produced by final 1.5 mm roller space had the best properties(MOR, MOE and IB strength) among boards produced by different final roller space. Also, they had the best properties(MOR and MOE) in bending test after 1 hour soaking treatment after 2 hour-boiling in water, which were similar to properties of boards in dry-condition. Thickness swelling(TS) of all boards was less than 12% required to the Korean Standards A 3014. Zephyr boards produced by final 1.5 mm roller space also had the lowest values among all of boards. Boards produced by non-treatment (in green condition) had the better strength than those of boards produced by different pre-treatment methods(boiling in water and in 0.3% NaOH) in bending test.

• Journal of the Korean Wood Science and Technology
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• v.30 no.1
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• pp.11-17
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• 2002

This study was performed to determine the characteristics of particleboard made from three-months-old bamboo, (Phyllostachys nigra var henonis Stapf) grown in Damyang district, Korea. Total 60 particleboards were manufactured with 1% of liquid wax emulsion using urea-formaldehyde resin content 9%,11% and 13%, respectively. The particle boards consisted of three layers, in which face layer had the same proportion of a weight 25% of the particleboard each. And the core layer had a weight 50% of the board. The core layer and face layer had the particle dimension passing 6 mesh (3.35 mm), 12 mesh (1.70 mm), respectively. The study was carried out to determine the effect of the growing time of 3 months and 3 years on particleboard properties. The physical and mechanical properties of boards were measured and compared to the Korean standard (KS) requirements of particle boards. The results were as follows; 1. The longer the growing time, the higher the density of bamboo. Density of the upper part of bamboo showed higher than that of lower part. 2. Density and moisture content of the two particle boards did not show significant differences. Three-months-old bamboo particleboard gave higher thickness swelling than three-years-old bamboo particleboard. Bamboo particleboard passed the thickness swelling test of KS. 3. The static bending and internal bond strength of three-months-old bamboo particleboard were higher than those of three-years-old bamboo. Increase of resin contents in bamboo particleboard increased bending and internal bond strength, proportionally. Strength properties of bamboo particle board were above KS. 4. Formaldehyde emission of all the bamboo particleboards satisfied E₂ level (5.0 mg/L) of KS F 3104.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.80-87
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• 2004

This study was carried out to improve the properties of powdered tannin adhesive(PT) by adding liquid tannin resin(LT) to PT in the manufacture of particleboard. Mixing the LT to PT from 50% to 100% by weight did not show any difference in particleboard properties, but the higher the powdered tannin resin ratio, the lower the properties of the board. The proper ratio of PT to LT was 30:70 for the improvement of PT-particleboard, unless LT lower than 70%. Internal bonding strength was in proportional to the amount of LT. Mixing amino adhesives and PT did not show any improvements in mechanical and physical properties of the board but they only acted as scavenger for the free formaldehyde.Manufacturing particle board with the adhesive of 30:70 (PT:LT) and by using double blender resulted in high-performance products of E₀ level of formaldehyde emission with high water resistance (U type; below 12%, M type; below 25%), as well as saving chip drying energy.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.9-16
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• 2004

This research was carried out to investigate the component isolation method from liquefied waste paper. and isolated component was analyzed by molecular weight distribution with gel chromatography and nitrobenzene-oxidation analysis. In the aspect of liquefaction ratio, wet defibration fiber are better than dry defibration fiber because of wet defiberation fiber was easy to access of chemical solution. The optimal liquefaction condition of waste paper was treated at 190℃ for 60 min(cresol 2 ㎖, water 4 ㎖, phosphoric acid 0.5 ㎖ based on waste paper 1 g). In the liquefied waste paper, lignin and carbohydrate were separated with two interfacial layer(cresol layer, water layer). In the chemical analysis of isolated lignin, molecular weight distribution of isolated lignin was below 1,000.

• Journal of the Korean Wood Science and Technology
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• v.32 no.5
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• pp.59-65
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• 2004

The present study aims to optimise the process parameters of fish glue and adhesion property through room temperature in terms of curing time and opened assembly time for attaining best adhesion strength to wood (Yellow birch, B. alleghaniensis). The uncured and cured fish glue have been characterised by TGA, DSC, FT-JR. It is observed that with increasing curing time up to 48 H, tensile lap shear strength of adhesive joint of fish glue to wood increases and decreases after 48 H. At 15 min. opened assembly time, lap shear strength increases up to 4833 kgf/cm² and decreases after 15 min.

• Journal of the Korean Wood Science and Technology
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• v.31 no.5
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• pp.80-87
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• 2003

This research was carried out to examine physical and mechanical properties of clay-woodceramics which were carbonized for 3 hours in a special furnace from 3 layers-clay-woodparticleboard made from pallet waste wood, phenol formaldehyde resin(hereafter PF, Non volatile content 52%, resin content 30%) and clay(10%, 20% and 30%). Carbonization temperature was 400℃, 600℃ and 800℃. The results are summarized as follows: 1. The higher the carbonization temperature, the higher the dimensional shrinkage and the lower the carbonization yield ratio. But the higher the clay addition, the lower the dimensional shrinkage and the higher carbonization yield ratio. 2. The higher the carbonization temperature, the higher the water absorption and the density. The higher the clay content, the higher the density. 3. The higher the carbonization temperature, the higher the bending Modulus of Rupture and bending Modulus of Elasticity.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.1-8
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• 2004

This study was carried out to investigate the sheet properties of Indian mallow Hanji, made by different pulping methods, such as alkali and sulfomethylated pulpings, and different stock compositions, various mixing ratios of bast fiber and woody core fibers. Indian mallow hanjis made from the sulfomethylated pulps had higher brightness and sheet strength than the alkali pulps. It was found that the brightness of sulfomethylated pulp was enough high without an extra-bleaching. In the mechanical properties of Indian mallow hanjis mixed with bast fiber and woody core stalk pulps, the sheet strength were decreased as wood core pulps contents were increased. The sheet formation were increased as the increase of woody core pulps contents, while the sheet strength decreased. Although the sulfomethylated pulping resulted in higher pulp yield, no morphological differences of fiber surfaces were shown as compared to the different pulping methods.

• Journal of the Korean Wood Science and Technology
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• v.31 no.5
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• pp.23-34
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• 2003

This study was carried out to investigate the mechanical properties of fabric E-glass fiber reinforced laminated timber. Specimens used to Korean red pine(Pinus densiflora) and Japanese larch(Larix kaemferi). Fabric E-glass fiber was inserted in the solid wood with aqueous polymer-isocyanate resin(MPU-500). The results were as follows: 1. Aqueous polymer-isocyanate resin(MPU-500) was good resin to manufacture laminated timber. specially, it was satisfied to property standard of construction laminated timber(KS F 3021) except for two ply glass fiber. 2. Bending and shear strengths of solid wood inserted with fabric glass fibers were not different from control solid wood. But, proportional limit bending stress was increased following the number of fabric glass fibers. Therefore, it was considered that to improve the bending and shear strength of fabric glass fiber reinforced laminated timber, the glass fiber thickness and its mesh should be modified to fitness following working conditions.

• Journal of the Korean Wood Science and Technology
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• v.2 no.3
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• pp.17-31
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• 1974