• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2001.04a
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• pp.66-68
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• 2001

• Animal cells and systems
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• v.3 no.2
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• pp.143-147
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• 1999

Annual production and redistribution of leaf litter were compared among three distinct understory patches in a temperate hardwood forest dominated by Quercus mongolica, Kalopanax pictus, Acer pseudo-sieboldianum, and Carpinus cordata. Two patches were located on a southwest-facing slope: one with an understory dominated by herbaceous plants (Patch S), and the other covered with evergreen dwarf bamboo, Sasa borealis (patch SS). The third patch was on the opposite slope with an understory dominated by herbaceous plants (Patch N). Annual leaf litterfall was averaged 330 g m$^{-2} yr$^{-2}$ in the three patches from 1994 to 1998. From mid-September 1996 to mid-September 1997, net transport of leaf litter over patch bound-aries was 1,824g m$^{-1}$ from Patch S to SS, 1,465g m$^{-1}$ from Patch S to N, and 886 g m$^{-1}$ from Patch SS to N. The amounts moving downslope out of Patch S, SS, and N were 2,548, 471, and 588g m$^{-1}$, respectively. When a mass balance approach was employed for the data of leaf litter transport, the results were relatively consistent with 216, 631, and 724g m$^{-2}$ of leaf litter stores in Patch S, SS, and N, respectively, in April 1997. This study suggests that leaf litter redistribution is largely regulated by aspect and understory type and exerts a significant effect on carbon processes in the forest ecosystem.

• Animal cells and systems
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• v.5 no.4
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• pp.319-325
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• 2001

Transport of colored papers and decomposition of leaf litter of Quercus mongolica, Acer pseudo-sieboldianum, and Kalopanax pictus were investigated on three patches differentiated by aspect and understory in a temperate hardwood forest. Two patches are represented by dwarf bamboo (Patch SS) and herbaceous plants (Patch S), respectively, Iying on a south-west-facing slope. The other patch (Patch N) is located on a northeastfacing slope with herbaceous plants. Colored papers were placed on the patches to understand the pattern of litter movement on the ground. Papers were move dispersed in Patch S than in the other two patches. Some of the colored papers placed in Patch S moved upward. The results suggest that the litter movement is affected by aspect and that the leaf litter is retained by dwarf bamboo in Patch SS. Decay constant of Q. mongolica was significantly (p＜0.05) lower than those of K. pictus and A. pseudo-sieboldianum. Decay rates of Q. mongolica were significantly different between Patches N and S and between Patches SS and S (p＜0.05). On the other hand, decay rates of the other species were not significantly different among the three patches. The results suggest that aspect and understory exert an influence on redistribution and decomposition of leaf litter and that the effects could be different among the plant species.

• Journal of Korean Society of Forest Science
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• v.89 no.4
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• pp.502-512
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• 2000

Old-growth development for two different second-growth northern hardwood stands in the North America was evaluated with a computer simulation. The two sites compared were a representative 77 year old even-aged stand (Phelps) with heavy dominance by pole size classes, and an older uneven-aged stand with some existing old-growth structural features (Wildcat Creek). Each stand was evaluated in its natural progress toward old-growth structural conditions with stand structure, size distribution of live and dead trees, percent stand area in canopy gaps, and visual canopy profile and overhead view. The Phelps stand reached the minimum structural threshold for the old-growth stage after 74 years. Only 13 years was required for Wildcat Creek stand to reach the old-growth threshold. During the 45 years of simulation, the diameter distributions of both stands became broader and flatter. DBH distribution of dead trees had a general descending trend over the simulation in each stand. Gaps at Phelps were typically small after 45 years. Gap area at Wildcat Creek was somewhat more constant over the 45 years of simulation but a big gap was formed because of the death of several adjacent large trees.

• Korean Journal of Plant Resources
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• v.22 no.4
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• pp.293-298
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• 2009

We prepared densified wood pellet by agricultural waste. The hemp woody core was used as replacing wood resource. Hemp was separated into the bast fiber and the woody core by hot steaming treatment. The hemp woody core had a similar lignin content(19.4%) and carbohydrate composition with hardwood(20-25% lignin in hardwood), respectively. Also, the hemp had a low ash content(0.5%), which resulted in a low ash formation in pellet burning. Heating value of the hemp pellet(18.40 MJ/kg) had a very similar to the pellet made by hardwoods. The hemp woody core could be replaced the hardwood for densified wood pellet.

• Journal of Sericultural and Entomological Science
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• v.33 no.2
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• pp.63-67
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• 1991

Various concentrations of ${\alpha}$-naphthalence acetic acid(NAA) as a root-promoting substance were tested in hardwood cutting of the mulberry(Morus bombycis Koidz., cultivar : Shinkwangppong) to make clear the callusing effect on the budding and root growth. Budding and shoot growth of cuttings were delayed at high concentrations of NAA within 10 days of callusing. Especially more severe is it at higher than 50ppm. More than 93% of them, however, budded in two weeks when callused at less than 100ppm NAA. Although rooting was accelerated at high concentration of NAA from the bigining of cutting, after that, rooting percentage increased to reach 100% in 35 days of cutting in any concentration except 150ppm with relatively low rooting. Root growth was utmostly accelerated at 50ppm NAA to show the highest amount in number, length and weight of roots per cutting although high concentration of it decreased mean root length.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.2
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• pp.83-90
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• 1997

An unbleached hardwood kraft pulp was bleached in vitro with partially purified manganese peroxidase (MnP) from the fungus Phanerochaete sordida YK-624 without the addition of MnSO$_4$ in the presence of oxalate, malonate or gluconate known as manganese chelator, When the pulp was treated without the addition of MnSO$_4$, the pulp brightness increased by about 10 points in the presence of 2 mM oxalate, but the brightness did not significantly increase in the presence of 50 mM malonate. Residual MnP activity decreased faster during the bleaching with MnP without MnSO$_4$ in the presence of malonate than in the presence of oxalate. Oxalate reduced MnO$_2$ which already existed in the pulp or was produced from $Mn^{2+}$ by oxidation with MnP and thus supplied $Mn^{2+}$ to the MnP system. Thus, bleaching of hardwood kraft pulp with MnP, using manganese originally existing in the pulp, became possible in the presence of oxalate, a good manganese chelator and reducing reagent. Properties of partially purified MnPs from liquid cultures of white rot fungi, Ganoderma sp. YK-505, Phanerochaete sordida YK-624 and Phanerochaete chrysosporium were compared. MnP from Ganoderma sp. YK-505 was superior to MnPs from P. sordida YK-624 and P. chrysosporium in stabilities against high temperature and high concentration of $H_2O$$_2$. The MnP from Ganoderma sp. YK-505 differed in pH-activity profile from other MnPs. These data suggest that MnP from Ganoderma sp. YK-505 has different structure from those of other fungi. Bleaching of hardwood kraft pulp using the MnP from ganoderma sp. YK-505 is now in progress.

• Journal of Conservation Science
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• v.5 no.2 s.6
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• pp.51-56
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• 1996

This paper deals with the restoration of ancient wooden bridge foundation which excavated in Seta river Shiga Prefecture, Japan. Shiga Archeological Research started a marine archeological investigation of the bridge foundation in 1987. The bridge foundation stricture excavated and have since then recovered about a lots of woods and another materials. The bridge foundation structure constructed log, timbers and stones. The species of those waterlogged wood were identified as two types, hardwood and softwood. Hardwood(log : Cyclobalanopsis) was used for below foundation and softwood (timber' Chamaecyparis obtusa Endl. Cupreessaceae) was used for base structure. One of those timber sample dated by dendrochronology, we asked Dr. Misutani*. The softwood gave a felling date of 567 A.D. In result, the ancient Seta bridge foundation structure had constructed between Asuka and Nara period. We healed the news that ancient bridge foundation excavated at Woljyongyo site in Kyongju, Korea 1987. The bridge foundation Setakarahashi is similar in plane and structure to Woljyongyo structures. The Woljyongyo site report had be of value for reference. We had planning to restore those woods. Hardwood log was got serious damage. The water content varies from 400 to $600\%$. The other timbers water content varies about $200\%$. In the Shiga Center for Archaeological Operations and the Azuchi Castle Archaeological Museum, we set up the PEG impregnation tank. Those wooden objects treated by PEG method. PEG with a molecular weight of 4000. The treatment results may be considered satisfactory. The ancient wooden Seta bridge was reconstructed in Biwako Museum which established in Oct. 1996. We must take care of indoor exhibition environments. (*Nara National Cultual Properties Research Institute).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.3
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• pp.59-65
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• 2011

The saw dust of tropical hardwood, Nyatoh(Palaquium Spp.), was used as a raw material for the preparation of the high valued microcrystalline cellulose(MCC). Three pulping methods, soda pulping, Kraft pulping, and acid-sulfite pulping were applied to obtain cellulose from the saw dust. The residual impurities were removed with the additional bleaching processes: (A) $ClO_2{\rightarrow}H_2O_2$; (B) $ClO_2{\rightarrow}O_3$; (C) $O_3$. For the acid treatment for MCC preparation, the $H_2SO_4$, with three concentration, 20%, 40%, 60% were applied and the effects of $H_2SO_4$ concentration on the properties of MCC were evaluated. The results indicated that the MCC obtained by acid-sulfite pulping followed with $O_3$ treatment and 40% $H_2SO_4$ treatment showed less residual lignin, higher brightness and crystallinity than that of Avicel MCC.

• Korean Journal of Plant Resources
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• v.13 no.2
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• pp.140-146
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• 2000

This study was conducted to determine the effect of cutting type, growth regulators and propagation media on the rooting and root growth of Roea davurica $P_{ALL}$. Three type of cutting, hardwood, half-softwood, softwood cutting and root cutting of Rosa davurica $P_{ALL}$, were used to study the rooting ability. There was no rooting in hardwood cutting while root cutting was appeared 100% of callus formation and rooting. The optimum conditions of softwood cutting for rooting were IAA 100ppm and rooton-F at vermiculite+perlite. The rate of rooting in treatment of rooton-F ranged from 10 to 60%, but such a good effect was not appeared in other growth regulators, IAA, NAA and IBA.