• Journal of the Korean Wood Science and Technology
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• v.28 no.1
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• pp.55-64
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• 2000

Culture maturity assessment can be used to control fruiting body flush timing. Culture maturity of sawdust-based substrate was evaluated by using oak mushroom, (Lentinula edodes (Berk.) Pegler). The influence of substrate water potential (${\psi}$) on the growth and fruiting of three genotypes of L. edodes was also investigated. Glucosamine content revealed a peak at the fruiting body senescent stage. Glucosamine increased steadily to the sporophore senescent stage, and sharply declined at crop treatment. Lipid phosphate and ergosterol contents peaked at pinning and button break stages, respectively. Therefore lipid phosphate and ergosterol contents would be considered as the convenient measurement for judging culture maturity and fruiting potentials. The substrate pH values before inoculation and on the fruiting stage were varied from 6.3 to 4.0. This pH changes were detected as changes in color from bluish purple to yellow by direct bromphenol blue(BPB) spraying, and shown a good correlation with fruit body yield of the 1 st flush. Concerning water potential of the cultures, a slight reduction of water potential, -0.5MPa, stimulated mycelial and colony growths on liquid, agar and sawdust-based substrates. The water potential of well-colonized matured substrate was -0.7MPa and -4.0MPa, before and after the fruiting, respectively. Excellent water providing capacity (higher ${\psi}$) is expected to well-matured cultures with a high density of mycelial colonization. Also, the substrate water potential significantly affected by the interaction between genotypes and spawn run time.

• Journal of Korean Society of Forest Science
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• v.77 no.2
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• pp.252-257
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• 1988

This study was carried out to investigate the physical and mechanical properties of sawdust boards combined with sycamore and polypropylene-net flakes. Both the sycamore and polypropylene-net flakes were adjusted to the sizes of $1.0{\times}1.0$, $1.0{\times}2.0$, and $1.5{\times}1.5cm^2$ and these flakes were mixed at 1, 2, 3, and 4% levels based on ovendry weights of sawdusts, respectively. The results obtained in this study were summarized as follows : 1. Thickness swellings of sawdust boards combined with sycamore flakes decreased with the increase of mixture levels and similar effects were also recognized in combination with polypropylene-net flakes. 2. Moduli of rupture both in sawdust boards combined with sycamore and polypropylene-net flakes increased with the increase of their mixture levels, and sawdust boards combined with sycamore flakes of $1.0{\times}2.0cm^2$ size and polypropylene-net flakes of $1.5{\times}1.5cm^2$ size showed higher moduli of rupture than control boards. 3. Moduli of elasticity both in sawdust hoards combined with sycamore and polypropylene-net flakes increased with the increase of their mixture levels as in moduli of rupture. 4. The physical and mechanical properties of sawdust boards combined with sycamore and polypropylene-net flakes were mainly dependent on aspect ratio of sycamore flakes and size of polypropylene-net flakes respectively, and these properties were improved with the respective increase of aspect ratio and size.

• Journal of the Korean Wood Science and Technology
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• v.48 no.1
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• pp.61-75
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• 2020

In this study, the environmentally friendly material charcoal was added to ricehusk, an agricultural by-product, and sawdust, which emerges during the sawing process, to produce board by mixing ratio and concentration levels of ricehusk and charcoal; it then investigated its physical properties for development purposes and achieved the following results. The water absorption and thickness swelling of the compounded board produced per adding ratio of ricehusk and charcoal showed a gradually decreasing tendency along with the increase in adding ratio of the charcoal, and as the density of the compounded board increased, the water absorption decreased, while the thickness swelling increased. The internal bond strength of the compounded board had indicated its highest value of 0.49N/㎟ at the density of 0.7g/㎤. This satisfied the quality standard for KSF 3104 Particleboard. The internal bond strength of the compounded board manufactured per adding ratio of ricehusk and charcoal showed a steady decrease with the decrease in the adding ratio of ricehusk, and an increase in the addingratio of the charcoal. Also, in cases when the ratio of the ricehusk and charcoal by KSF 3104 quality standard were 35:5 and 30:10, it satisfied the quality standard of 15.0-type, whereas it satisfied the 13.0-type quality standard if the ratios were 25:15 and 20:20. It showed a tendency of increasing hardness of the compounded board with the increase in density, and decreasing hardness with the increase in the adding ratio of the charcoal.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.35-44
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• 2004

The water soluble fractions(WSF) from Japanese larch wood were isolated, purified by anion exchange resin and Sephadex gel filtration and identified its chemical structure by means of periodate oxidation and methylation reactions. Its major components are arabinose and galactose (1 : 3.4). Based on the results of periodate oxidation, methylation and gas chromatographic analysis of purified WSF, main chain is composed of β-1,3-glycosidic linkage among D-galactopyranoses, and two different side chains; β-1,6-glycosidic linkage among 2-3 units of D-galactopyranoses and β-1,6-glycosidic linkage between 1-2 units of D-galactopyranose and L-arabinopyranose. Addition of WSF to culture media of oak mushroom (Lentinula edodes) accelerated the mycelial growth. In the case of PDA cultures, 2 percent addition of WSF in Sanlim No. 6 strain and 4 percent of WSF in Mok-H strain mostly enhanced the mycelial growth of the mushroom. In the case of sawdust cultures, 4 percent addition of WSF in two strains showed the best mycelial growth. High percentages addition of WSF inhibited mycelial growth of the mushroom. Mushroom production was increased with addition of WSF. By the addition of WSF, ergosterol contents in the media were quite high at the colonized stage and rapidly increased at the fruiting stage. Therefore the ergosterol content could be utilized as an indicator to evaluate the culture maturity for the mushroom fruiting.

• Journal of agriculture & life science
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• v.43 no.3
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• pp.15-26
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• 2009

This study was undertaken to determine inhibitory compounds from extracts of the softwood (larix leptolepis, Pseudotsuga menziesii) sawdust against Trichoderma spp. The sawdust of L. leptolepis and P. menziesii were hot water extracted, which were with fraction extracted organic solvents. The organic solvent extractions were carried out by n-hexane, methylene chloride, ethyl acetate. The antifungal activity of hot water extracts of L. leptolepis sawdust was determined to be 20.6% inhibition at a concentration of 1,000 ppm against Trichoderma spp. The antifungal activity of P. menziesii sawdust was outstanding about 60.3% against Trichoderma spp. The yields of the fractions of n-hexane soluble, methylene chloride soluble and ethyl acetate soluble from the hot water extract of L. leptolepis sawdust were 4.0%, 6.0% and 8.0%, repectively. However, the yields of the fractions of three solvents of P. menziesii sawdust were 8.0%, 13.0 and 14.0% correspondingly. The antifungal activity of n-hexane soluble fraction from hot water extracts of L. leptolepis sawdust was highest to about 68.5% to 79.9% against Trichoderma spp. compared to others. The antifungal activities of n-hexane soluble fraction from hot water extracts of P. menziesii sawdust showed 68.5%, 71.4%. 71.9%, 75.7% and 82.3% against T. aggressivum, T. atroviride, T. harzianum, T. koningii and T.viride, respectively. The n-hexane soluble fraction revealed much higher antifungal activity than the other fractions did. This study demonstrated that the n-hexane fraction of the hot water extracts of L. leptolepis and P. menziesii exhibited the greatest antifungal activity against Trichoderma spp.

• Journal of Forest and Environmental Science
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• v.36 no.3
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• pp.219-224
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• 2020

Urea formaldehyde resins are widely used in the manufacturing of wood composite and their usage is always combined with release of formaldehyde characterized to be hazardous to health during and after the manufacturing of the products. This study investigates the effectiveness of wood-based adhesive from oil of pyrolysed Triplochiton scleroxylon sawdust for the production of composite board. The wood-derived Pyrolytic Oil (PyO) was blended with Urea Formaldehyde (UF) resin to formed Pyrolytic Oil-Urea Formaldehyde (PyOUF). The obtained PyOUF called Wood-Based Adhesives at four blends and control (UF) viz; 1:1, 1:2, 1:3, 2:1, 1:3 were further employed to prepare the composite board and test for their bonding strength by physical (water absorption-WA and thickness swelling-Th.S) and mechanical properties (modulus of elasticity-MOE, modulus of rupture-MOR, and impact bending-IB). Data obtained was analysed using analysis of variance at α 0.05. The result of analysis of variance conducted on physical properties show significant difference (p≤0.05) between the WA values obtained when testing the different blending proportion of PyOUF and likewise between 2 and 24 h of immersion. PyOUF had significant effect (p≤0.05) on Th. S for 24 h but no significant different (p>0.05) for the 2 h period of soaking. The analysis of variance on mechanical properties of the composite board (MOE, MOR, and IB) show significance differences (p≤0.05) between the strength values obtained when testing the different ratios of PyO with UF. PyO content influenced the properties of the boards and it is evident that PyO can be used in the manufacture of composite board.

• Journal of the Korean Wood Science and Technology
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• v.14 no.3
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• pp.23-29
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• 1986

Alakline peroxide pretreatment for the delignification of poplar wood was performed. sinceit is a simple and efficent method for enhancing the enzymatic digestibility of wood residues. Approximately one-half of their lignin and most of the hemicellulose present in poplar wood were removed when the wood sawdust was reacted at 25$^{\circ}C$ for 100 hrs in an alkaline solution (pH 11.5) of 1% peroxide. The rate of decomposition as well as the saccharification efficiency were enhanced up to 350% and 260% respectively in comparision with those of the controll. This enhancement is comparable with that pretreated with 1% sodium hydroxide and 20% peracetic acid successively. The advantages of alkaline peroxide as delignifying agents against other chemicals were also discussed.

• Journal of the Korean Wood Science and Technology
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• v.21 no.1
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• pp.7-14
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• 1993

To increase the production of mushrooms and the economic efficiency of mushroom cultivation, the pinchips(PC) and sawdusts(SD) of three Korean oak species were tested as cultivating media for Lentinus edodes with varing the composition of the media. The results are as follows. 1. Organic acids(tannic acid and citric acid), which were added in the PC medium to enrich the quality of mushrooms, did not increase the growths of the mycelia and the quality. 2. The mushrooms were able to be harvrested from six months after beginning the cultivation. No significant differences were found among the qualities of the mushrooms produced by various treatments. 3. The production rate of mushroom was relatively high with, 28.4~29.3% (700~730gr./2,500gr pack). The net profit estimated was about 1,450 won per pack.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.3
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• pp.123-131
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• 2006

This paper reports the apparatus and method for the safe treatment of pentachlorophenol(PCP)-treated ammunition box by solvent extraction. Experimental variables were chosen as the composition of solvents, types of substance(chips and sawdust), temperatures and sonication to obtain maximum PCP removal from wood samples of the dismantled ammunition box. Up to 99% of PCP in the wood chip was extracted within 2 hours at room temperature when using methanol as the solvent. The extraction volume ratio of methanol per dried sample was about 10. Type of samples, extraction temperature and sonification showed little effects on PCP extraction. Based on this study, a resource recycling system for the treatment of ammunition boxes was recommended.

• Journal of the Korean Wood Science and Technology
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• v.35 no.3
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• pp.22-28
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• 2007

Using woodceramics made from sawdust board of pine thinning logs, changes in surface temperature were investigated, by the heating rate and keeping time at maximum temperature. The heating rate of $2^{\circ}C/min$ and keeping time at maximum temperature 1 hour, were the highest in surface temperature. Also, it was found that woodcermics maintained heat for a long time because the descending velocity of their surface temperature was slower than that of the heater.