• Journal of the Korean Wood Science and Technology
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• v.51 no.3
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• pp.173-182
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• 2023

Color is an attribute of visual perception and can be an important factor that affects the preference of customers toward bamboo and wood products. Solar radiation can discolor bamboo surfaces and initiate cracking. The purpose of this study is to investigate the effects of an ultraviolet (UV)-protective coating on the photodiscoloration of untreated and heat-treated Phyllostachys bambusoides bamboo surfaces. Artificial UVA radiators are set at a UVA irradiance of 2,000 W/m² to accelerate the aging of the outer surfaces of hot-air-dried and heat-treated bamboo samples. Half of the samples are coated with transparent UV-protective paint. As the UVA radiation progresses, the discoloration prevention efficiency (DPE) of the UV-protective coating on all samples decreases gradually. The DPEs of the hot-air-dried samples are estimated to be 31.4% and 18.8% after 21 and 72 hours of artificial UVA radiation, respectively. The heat-treated samples exhibit similar trends (29.0% after 21 hours and 10.3% after 72 hours). Recoating the UV-protective paint periodically every six months is expected to minimize the discoloration of the bamboo's outer surface.

• Journal of the Korean Wood Science and Technology
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• v.49 no.6
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• pp.566-573
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• 2021

We investigated color changes on the outer surfaces of Phyllostachys bambusoides bam-boo by heat treatment under three different temperatures (180℃, 200℃, and 220℃) for three different durations (60 min, 90 min, and 120 min). A method of predicting the bam-boo surface color change after heat treatment was developed to provide valuable information and increase the added value of domestic bamboo products. The three average color parameters L^*, a^*, and b^* decreased, and the overall color changes increased as the severity factor increased. The values of L^* × a^* × b^* were highly related to the severity factor, and the optimal duration time for the desired bamboo surface color with a certain heat-treatment temperature could be estimated.

• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.107-113
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• 2018

In this study, the 3D printer filaments were manufactured by using the representative eco-friendly material, bio-composite. Bio-composites were made by incorporating biodegradable polymer of poly lactic acid (PLA) as the matrix and bamboo flour as the filler. The bamboos which were used in this experiment are Phyllostachys bambusoides, Phyllostachys nigra var. henonis, and Phyllostachys pubescen grown in Damyang district in Korea, and the mixture ratio between bamboo flour and PLA were set 10/90, 20/80, 30/70 by weight standard. Also, tensile strength of bamboo/PLA bio-composites manufactured with three kinds of bamboo were estimated and compared. In this result, the highest estimated bio-composites was Phyllostachys bambusoides flour/PLA which mixture ratio was 10/90, that is, it was the most suitable bamboo/PLA bio-composites for manufacturing 3D printer filament.

• Journal of the Korea Furniture Society
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• v.20 no.5
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• pp.480-489
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• 2009

This study was carried out to develop the core technology for the manufacturing the flat floor panel with the bamboo grown in Damyang region maintaining its indigenous merits. Using capital bamboo(Phyllostachys bambusoides) of Damyang with superior physical and working properties, Authors have standardized the core technologies for the integrated production of flat floor panel using this superior bamboo i.e, washing, splitting, flattening, blasting, and overlaying over plywood. It is expected to increase the income from bamboo forest and to enhance the image of the eco-city, Damyang with this technological development. Additional quality assuring test and economical analysis for the industralization as building material will be performed.

• Journal of the Korean Society of Food Culture
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• v.33 no.3
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• pp.283-290
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• 2018

This study examined the quality characteristics and anti-oral microbial activity of bamboo leaf jelly prepared with different 5 levels (0, 10, 20, 30, and 40%) of bamboo (Phyllostachys nigra var. henonis) leaf extract. The sugar contents of bamboo leaf jelly were increased significantly by increasing the level of bamboo leaf extract. The luminance and Hunter's a values of the jelly samples increased with increasing bamboo leaf extract, but the 40% bamboo leaf jelly had the lowest Hunter's b values. The hardness, adhesiveness, gumminess, and chewiness increased significantly with increasing bamboo leaf extract. Among the mechanical properties, only the flavor of the jelly with 30 and 40% bamboo leaf extract were increased significantly. The extract of bamboo leaves had strong antimicrobial activity against S. mutans, S. sobriuns, P. gingivalis, and P. intermedia at a concentration of 40%. These results suggest that bamboo leaf extract can be useful in the production of high quality jelly.

• Journal of Korea Foresty Energy
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• v.22 no.1
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• pp.17-23
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• 2003

Three different aged Chinese bamboo (Phyllostachys pubescense; 3, 5, and 7 years) was carbonized using three different types of kilns (special, improved and simple kiln) and their physicochemical charcoal properties were investigated. The fixed carbon of the bamboo charcoal prepared from the special kiln (800 - $1,000^{\circ}C$) tended to be decreased, while the specific surface area tended to be increased, according to the increase of bamboo ages. The bamboo charcoal prepared from the 5-year-aged showed the highest value in iodine value. In the improved kiln (600 - $700^{\circ}C$), the specific surface area and the iodine value increased with the growth period. In the simple kiln (400 - $500^{\circ}C$), the amount of volatile matter of the bamboo charcoal was approximately two times higher than that obtained from the special and improved kilns. Despite of the high amount of volatile matter in the simple kiln, the fixed carbon was more than 80%. The 5-year-aged bamboo charcoal showed the highest levels in specific surface area and iodine value. The physical properties of the bamboo charcoals prepared from the 3- and 5-year-aged Chinese bamboo were relatively worse those of Korean bamboo of the same ages. It was probably thought caused by less dense structure of the Chinese bamboo of 3- and 5-year-aged than the domestic in morphological aspects.

• Journal of the Korean Wood Science and Technology
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• v.46 no.3
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• pp.231-240
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• 2018

Bamboo is one of the major biomass resources that have many advantages such as fast growing, easy cultivation, short rotation, and a relatively lower price. In this study, the anatomical characteristics of Moso bamboo (Phyllostachys pubescens) by age from one-year-old to five-year-old were examined by optical and scanning electron microscopy. Also, the crystalline properties such as relative crystallinity and crystallite width were investigated by an X-ray diffraction method. In one-year-old bamboo xylem, a few vascular bundles showed missing bundle sheath in near the intercellular space. Moreover, one-year-old bamboo had the shortest fiber length and the smallest values in vessel diameter, width of vascular bundle, and thickness of inner layer. One-year-old bamboo also showed the smallest values in the crystallinity and crystallite width. Near epidermis samples had longer fiber length and greater vascular bundle spacing than near pith samples. Relative crystallinity and crystallite width near the epidermis were also higher than near the pith. This study revealed significant differences in qualitative and quantitative anatomical characteristics between one-year-old and two-year- or more old Moso bamboos. It is concluded that the structural differences by bamboo age can be used to differentiate the characteristics of juvenile and mature bamboo.

• Journal of Korean Society of Forest Science
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• v.34 no.1
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• pp.47-56
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• 1977

I have investigated and compared the morphology of vascular bundle shown in the section of culm wall of bamboo trees growing on Mt. Jiri which were classified by Grosser and Liese with their methods of morphological classification. The results obtained were as follows: 1. It was shown that there are no b.g.i. types of bamboo classified by Grosser and Liese among the bamboo trees on Mt. Jiri (Phyllostachys and Sasa). 2. As for the thickness of the culm wall in the culm, it was shown that the culm wall of the Phyllostachys becomes thinner in proportion to its nearness to the upper part of the tree, but no distinctive difference appeared in the Sasa. 3. The c, d, and e types of Sasa were the same as those of the Phyllostachys, but there was a vascular bundle type of the a' type, which was quite different from that of the Phyllostachys. 4. It was shown that the a', d, and e types of Sasa were distributed in a zone less than 500m above sea level, but no a' type was distributed in the high mountain area except for the c, d and e types which ranged from 600m to 1000m above sea level. Such facts mean that the vascular bundle sheath has changed in quantity because of the height of mountain. 5. In general, as compared with the Phyllostachys, the Sasa (types a, c, d and e which included a new type a) have fewer vascular bundles. 6. Considering the above results, it is thought that not by the current Sasa classification method based on observation of the the study of Sasa form the outside, but by a new method of classification based on the aspect of the physiological construction as seen from the inside wall is advanced. I believe this new method of classification to be a first step towards an epoch-making methodological advance and encourage the further study of it.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.67-73
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• 1995

This study was undertaken to investigate the effect of heat treatment on the dynamic viscoelasticity of three species of Phyllostachys bambusoides, Phyllostachys nigra var. henonis and Phyllostachys pubescens, grown in southern Korea. The bamboo was treated for 3~24 hours at $60{\sim}180^{\circ}C$, and then was treated in a climatic chamber for 3~48 hours at $40^{\circ}C$ and 95% relative humidity. The results obtained are summarized as follows : 1. Dynamic Young's modulus decreased with increasing temperature and duration of the heat treatment. 2. Internal friction decreased with increasing treatment duration. 3. Moisture absorption decreased with increasing temperature and duration of the heat treatment. 4. Dynamic viscoelasticity decreased, whereas internal friction slowly increased, with increasing moisture content.

• Journal of Korea Foresty Energy
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• v.22 no.2
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• pp.26-35
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• 2003

Bamboo strand board (BSB) was made with Phyllostachys banbusoides growing in Damyang district. Physical and mechanical properties of this BSB were summarized as follows; The specific gravity of BSB was 0.63∼0.79. Specific gravity decreased slightly with the thickness and length of BSB. Moisture content of BSB manufactured was 5.8∼6.9%. The absorption ate of BSB (42∼48%) did not show any relationship with the thickness and length of BSB. The thickness swelling rate of BSB was 13.9∼17.0%, relatively higher than any other panel products. Thickness swelling rate increased with the thickness of BSB, showing the strand thickness influenced much more on the rate of thickness swelling of BSB than the length of strand. The 3-point bending strength of BSB was 98∼126kgf/$\textrm{cm}^2$. Bending strength of showed the tendency of increase with the increased length of BSB, but with the decreased thickness. In particular, the length of BSB showed more effect on the increase of bending strength of BSB than the thickness of BSB. The compression strength perpendicular to BSB surface was 411 ∼ 465 kgf/$\textrm{cm}^2$, and the optimal length of strand for the 1mm- and 2mm-thickness of strand was 40mm and 60mm, respectively. Compression strength paralleled to BSD was 160∼221kgf/$\textrm{cm}^2$ and the optimal length of strand for the 2mm-thickness of strand appeared to be 60mm. The present work showed that appearance, physical and mechanical strength of BSB appeared quite positive in terms of board qualities, suggesting that bamboo would be appropriate for the production of board materials. In addition, our work showed that the crucial factor for determining the mechanical characteristics of BSB was the dimension of strand.