• Journal of Korean Society of Forest Science
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• v.26 no.1
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• pp.57-65
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• 1975

This study was carried out to examine the effect of manufacturing factors on physical properties of hardboard (S.I.S) made from the juvenile wood of sycamore (Platanus orientalis L.) The results obtained may be summarized as follows: 1. The difference among the yields of pulp treated with preheat time (defibrate condition) was significant in those of treatments. There was no difference in the yield of pulp treated with defibrate time. The yields of pulp on the tree age classes were shown the difference by 2<4<6<8 years. 2. The specific gravities of hardboard that were treated with hot pressing conditions showed us significantly in those of treatments. There was no difference on the specific gravities among hardboards, treated with resin and wax contents. But in all cases of the specific gravities satisfied the standard which specified the KS F 3203 (Hardboard) 3. The moisture contents of hardboard satisfied the standard which calls for 13-percent below. There were difference in moisture contents between hardboard, treated with preheating time, resin and wax contents and hot pressing conditions. And the moisture contents of hardboard on the tree age classes showed the difference by 2<4<6<8 years. 4. The water absorption and thickness swelling of hardboard treated with defibrations, resin and wax contents, and hot pressing conditions were significant in those of treatments. And the water absorption and thickness swelling of hardboard on the tree age classes showed us the significant difference by 8<6<4<2 years. 5. The difference among the flexural strength in using tested three conditions showed us the difference by defibration$200kg/cm^2$) of hardboard, it is likely to be recommened that the juvenile wood of sycamore is valuable for the raw materials of hardboards.

• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.424-429
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• 2016

In this study, the carbonized boards were manufactured from different types of wood-based panel and then their moisture absorption/desorption properties were investigated and compared. The carbonization temperature was maximum $600^{\circ}C$ with 2 h maintains. Test results showed higher absorption/desorption capacity on carbonized plywood than carbonized MDF, PB, and OSB, respectively. However, carbonized MDF, OSB, and plywood had similar absorption/desorption rate per hour. It means carbonized OSB and plywood can transfer moisture into deeper side and then possibly hold more amount of water. Based on SEM images, carbonized OSB and plywood showed more like wood structure, while carbonized MDF and PB had only wood fiber or/and chunk of wood fragments. Therefore, original wood structure may affect moisture absorption/desorption capacity. In order to manufacture high moisture absorbing/desorbing carbonized board, wood structure should be considered and then carbonized.

• Journal of the Korean Wood Science and Technology
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• v.33 no.4 s.132
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• pp.60-65
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• 2005

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 wood core fibers. Indian mallow Hanjis made with 60% of woody core pulps were shown better Chinese ink spreading distance than those of the others. The Chinese ink spreading distance of the Indian mallow Hanjis made from bast fiber pulp only were unsuitable for Hwaseonji. The Chinese ink spreading distance of Indian mallow Hanji was closely related to the mixing ratio of long fiber and short fiber. Especially sulfomethylated pulping method was superior to alkali pulping method.

• Journal of agriculture & life science
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• v.44 no.4
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• pp.21-27
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• 2010

This study was carried out to investigate the properties of woodceramics made from woody part of Broussonetia Kazinoki at different carbonizing temperatures of $600^{\circ}C$, $800^{\circ}C$, $1000^{\circ}C$and $1200^{\circ}C$. The physical and mechanical properties increased with increasing carbonizing temperature. The highest mean values of density, bending strength, Brinell hardness and compressive strength were $0.62g/cm^3$, $79kgf/cm^2$, $203kgf/cm^2$ and $129kgf/cm^2$, respectively. There were close correlations between density and bending strength, Brinell hardness and compressive strength and MOE and MOR.

• Journal of Mushroom
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• v.16 no.4
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• pp.272-278
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• 2018

Lignin degrading enzymes from Lentinula edodes have broad substrate specificities, and therefore can degrade a variety of recalcitrant compounds. In this study, the lignolytic biodegradation was investigated in five different L. edodes fungi (Chunbaegko, Sanjo 303ho, Poongnyunko, Baekhwahyang, and Soohyangko). The fungi were evaluated for their ability to decolorize Remazol Brilliant Blue R (RBBR) in malt extract broth medium. Sanjo 303ho, Poongnyunko, Baekhwahyang, and Soohyangko rapidly decolorized RBBR within 7 days. The activities of manganese peroxidase (MnP) and laccase were determined in the absence and presence of lignin. Poongnyunko displayed the highest ligninolytic activity on day 7 of incubation (2,809 U/mg and 2,230 U/mg for MnP and laccase, respectively).

• Journal of the Korean Wood Science and Technology
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• v.30 no.1
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• pp.1-10
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• 2002

The aim of this research was to investigate the manufacturing possibility of the paper sludge-synthetic fiber-wood fiber composite. Three levels of the formulation of paper sludge, synthetic fiber and wood fiber (5:5:90, 15:15:70, 25:25:50), two types of adhesive (PMDI, urea-formaldehyde resin) and three levels of density(0.7, 0.8, 0.9) were designed. From the test result, composites with similar or better properties, when compared with commercial fiberboard, appeared to be possible by the addition of up to 30~50% paper sludge and synthetic fiber into wood fiber.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.303-311
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• 1986

This work was designed as basic studies on the development of diet for the treatment of obesity. The effect of alginic acid which is the major component of brown algae was investigated by comparing with agar, cellulose, carboxymethylcellulose (CMC), chitin, and lignin as dietary fibers. These dietary fibers ($10\%$) supplemented to basic diet were fed ad libitum to Sprague Dawley rat for 4 weeks, and the inhibitory effects on obesity were evaluated by measuring body weight gain and feed efficiency, the content of glucose and cholesterol in serum, lipase activity in serum, lipid content in liver, adipose tissue around epididymis and ovarium, and Lee index etc. Among the inhibitory effect of these dietary fibers on obesity, lignin was the most effective (p<0.001), followed by Na-alginate (p<0.01) for body weight gain, but lignin was the most effective, followed by CMC, and followed by Na-alginate for feed efficiency (p<0.001). In the inhibitory effects on lipid accumulation in liver and adipose tissue around epididymis and ovarium, lignin and Na-alginate group among these dietary fibers were more effective than others, but there was no significant difference between male and female. The inhibitory effect on obesity evaluated by Lee index was effective in the order of Na-alginate>lignin>CMC>chitin>cellulose (p<0.001). The decreasing effects of lipid content in liver by dietary fibers were found in the order of agar>CMC>cellulose>Na-alginate>chitin>lignin (p<0.001). Glucose content in serum was significantly decreased in cases of CMC, lignin and Na-alginate, whereas a slight difference was found in chitin, but cholesterol content in serum was decreased for all dietary fibers examined except cellulose group. The increasing effect of lipase activity in plasma was found in cases of Na-alginate and chitin, while cellulose, CMC and lignin groups were decreased.

• Journal of the Korean Wood Science and Technology
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• v.38 no.3
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• pp.185-190
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• 2010

This study was focused to make a wooden plate that is engraved with writings or pictures on the medium density fiberboard (MDF), and then to produce a calligraphy-carving artwork by carbonization of the carved MDF. The external appearances and anatomical changes were investigated on the carbonized MDF and aesthetic characteristics was also discussed. No split and no twist were found after the carbonization (at $850^{\circ}C$) of the calligraphy-encarved MDF, shrinkages of the MDF were observed with portions of 21.8% in length, 18.8% in width and 43.5% in thickness, and 69.2% of weight loss with density decrease of 14.8% were observed as well. From the observation of the carbonized board by a scanning electron microscope, specific phenomena were found: the adhesives, surrounding the fiber's surface and pits, were carbonized, the woody fibers were changed smoothly, the pits were opened, the fiber' size was uniformized, and the organization was compacted. By the combination of handmade calligraphy-woodcarving and crack-free carbonizing methods, it was able to find a new method for manufacture carbonized calligraphy-woodcarving artwork. It is concluded that the calligraphy-woodcarving artwork using carbonized board can be a new access for the eco-friendly art that has the advantage of the functionality of charcoal and the aesthetic of calligraphy-woodcarving simultaneously.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.43-49
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• 2007

Anatomical properties of Kenaf (Hibiscus cannabinus L.) planted in a reclaimed-land of Korea were examined to understand the growth characteristics by an optical and scanning electron microscopy. The samples of kenaf were taken from four positions of the stem (3, 35, 70, 105 cm above from the ground) in four growth periods (July. August, September, October) from seeding planted in the middle of May. Bast fiber, phloem rays, cortex parenchyma cells and sieve tube members were observed in phloem, and vessel elements, fibers and rays in xylem. Solitary and multiple radial pores existed in xylem. The cell types of ray parenchyma in radial section were procumbent, upright, and square. The intervascular pitting showed an alternate type. Xylem proportion, the number of bast fibers and dimension of phloem rays increased with increasing growth period, and decreased with increasing stem height. The proportion of multiseriate rays was higher than that of uniseriate and biseriate rays in xylem with increasing growth period. On the other hand, The proportion of multiseriate rays was lower than that of uniseriate and biseriate rays in xylem with increasing stem height.

• Journal of the Korean Wood Science and Technology
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• v.28 no.1
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• pp.18-27
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• 2000

Even the same materials are assembled in flush door skin panel, warping is not simply prevented under the changes of environmental conditions since wood and wood-based material have large variations in their physical and mechanical properties. The parameters such as linear movement coefficient(LMC), modulus of elasticity (MOE), required to predict warping could be estimated by oven drying method and dynamic method instead of American Society for Testing Materials(ASTM) procedure. The relationship between warping and LMC was curvilinear, while it between warping and MOE was linear. LMC had a larger effect on warping than MOE. Material propensity of skin panel such as hardboard and plywood showed normal distributions. The variation of material properties, however, was much larger in plywood than in hardboard. Monte Carlo simulation also indicated that rejection ratio of flush door due to the occurrence of warping could be predicted with consideration of the relationship of warping and parameters of probability distribution of MOE, LMC, and moisture content.