• Journal of the Korean Wood Science and Technology
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• v.20 no.3
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• pp.55-60
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• 1992

Japanese red pine (Pinus densiflora S. et. Z.) decayed by brown-rot fungi Tyromyces palustris and Gloeophyllum trabeum were subjected to X-ray diffraction analysis and infrared spectral examinations. Pine woods decayed by T. palustris showed the increase of relative crystallinity in the initial stage of degradation. When the weight loss was above 30%, then the crystallinity went down slowly. In contrast, the wood samples degraded by G. trabeum showed the decrease of crystallinity from the beginning stage of decay. The changes of crystallinity in brown-rotted woods suggested that the degradation rate of crystalline cellulose was varied with the brown rot fungal species. X-ray diffraction analyses also indicated that crystalline cellulose was much more slowly broken down than the amorphous one. The most notable difference in the IR spectra of the brown-rotted wood samples was that the adsorption band centered at 1,730$cm^{-1}$ was significantly diminished in the decayed wood. indicating the degradation of hemicellulose by brown-rot fungi. However, no marked changes of intensities at 1,000, 1,060 and 1,040$cm^{-1}$ were observed in the brown rotted wood samples, suggesting that crystal line cellulose was resistant against the attack by brown rot fungi.

• Journal of Korea Foresty Energy
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• v.18 no.2
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• pp.62-69
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• 1999

Lignin in wood cell walls influeced the transformation of the cellulose crystal structure during mercerization. Samples of sound and decayed woods by white rot fungus of Quercus mongolica were treated with 20% aquous NaOH solution, followed by washing and drying, and delignified. The effect of delignification on cellulose structure was investigated by a series of an X-ray diffraction analysis and ultraviolet(UV) microscopy. Delignification of alkali-treated woods did not influence their cellulose crystal structures. It may be concluded that lignin prevents the swelling of wood cellulose during mercerization and restrain the intermingling of cellulose chains.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.1-9
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• 1995

This study was carried out to experiment the dimensional stabilization of woods of red pine (Pinus densiflora S. et Z.) and sugi(Cryptomeria japonica D. Don) by vacuum impregnation of polyehtylene glycols(PEG) with mo. wt. 200, 400, 600, 1000; polypropylene glycols (PPG) with mo. wt. 425,725 ; PEG-acryloylates, and PPG-acryloylates synthesized, and then by water soaking. The results obtained are as follows: 1. The density of sapwood and heartwood was different from each other in both species. 2. The PEG and PEG-macromers with lower molecular weight by impregnation has increased the density of wood specimens more higher, thereby caused their higher volume expansion, and those with higher molecular weight than 600 has tended to down their density increment. 3. Before and after water soaking, the density decrease of specimen impregnated was high in woods impregnated with simple PEG and PPG, while lower in specimens impregnated with PEG-macromers and PPG-macromers. 4. So PEG-macromer was expected to hold the original dimension of decayed wood for antiques, but it was necessary to develop another penetration method as well as aqueous solvent.

• The Korean Journal of Soil Zoology
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• v.2 no.1
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• pp.59-64
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• 1997

A study was carried out to investigate the distribution of termites at the southern part of Korea between 1995 and 1996. During the survey, termite samples were collected from the randomly selected areas. Most of thern were collected from the decayed woods in dead trees (usually in pine trees), but some were also collected from woodern walls, floors in houses, or in matured bed logs at the mushroom cultivating areas. Damage by this termite species were also observed by Kim and Hwang (1996) who investigated the insect pests of mushroom in the southern part of Korea. To control the termites, it is urgent to identify them and to conduct ecological study of termites. Thus, we firstly identified termites which were collected from the sampling areas including houses and mushrooms cultivating fields. All termite samples were identified as Reticulitermes speratus. However, there were several morphological differences among them according to the collected areas, and the samples were reexamined, identified and divided into subspecies as R. speratus kyushuensis.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.2
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• pp.8-14
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• 1999

A screening has been performed to find hyper-ligninolytic fungi, which degtrade beech and pine lignin extensively in order to broaden the understanding of the ligninolytic enzymes elaborated by various white-rot fungi. One hundred and twenty two ligninolytic strains were selected from decayed woods with a selective medium for screening ligninolytic wood-rotting fungi. Two of them, Phanerochaete sordida YK-624 and YK-472, showed much higher ligninolytic activity and selectivity in beech-wood degradation than typical lignin-degrading fungi, phanerochaete chrysosporium and Coriolus versicolor. They also degraded birch dioxane lignin and residual lignin in unbleached kraft pulp(UKP) much more extensively than P. chrysosporium and C. versicolor. During fungal treatment of beech wood-powder, the fungus strain P. sordida YK-624 showed higher activity of extracellular manganese peroxidase (MnP) in the medium than P. chrysosporium. It also showed MnP activity, which would not be lignin peroxidast during treatment of oxygen-bleached kraft pulp(OKP) and under enzyme-inducing conditin.

• Journal of the Korean Wood Science and Technology
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• v.32 no.3
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• pp.79-87
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• 2004

The objectives of this study were to select superior fungus for lignin degradation and to decolor dyes by selected fungus. Ligninolytic fungi were screened and isolated from decayed woods. Ten ligninolytic fungi were selected by ligninolytic enzyme activity on the PDA media containing rhemazol brilliant blue R, guaiacol and gallic acid. Their lignin degradation abilities were tested on the extractive-free wood powder of Quercus acutissima and Pinus densiflora. As a result, 8J-28 was selected as superior fungus for lignin degradation. Also, decolorization abilities of dyes were examined by shaking and static culture. And congo red, crystal violet, poly R-478, methylene blue used to investigate decolorization abilities of dyes. As a result, 8J-28 showed over 90% in decolorization of congo red, crystal violet, poly R-478.

• Journal of the Korean Wood Science and Technology
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• v.31 no.4
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• pp.71-80
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• 2003

The lignin degrading fungi were isolated from decayed woods and fruiting bodies gathered in forest area. Lignin degradation ability was investigated by Klason lignin of microbial treated pine wood. Among selected fungi, CJ-6 had 49.48% Klason lignin loss which was greater than 40.58% shown by Trametes versicolor that it is known as a typical lignin degrading fungus. Also, the biodegradation process and morphological features of degraded pine wood by selected fungi were observed with the scanning electron microscope. At the stage of 20 days incubation, mycelia invasion was observed without any failure of wood structure. At 60 days, wood decay was gone in some degree and one part of tracheid and ray wall was destroyed. At 100 days, tracheid wall was severely destroyed, and distinction between ray cell was difficult as cell wall was decayed much.

• Journal of Conservation Science
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• v.2 no.2 s.2
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• pp.15-24
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• 1993

To understand the morphological change of ancient woods, samples classified by cell type, burial environment and species were collected and observed using microscopy. Decay of wood by cell type could classified into two types. First, degraded secondary wall was formed granular residues in $S_2$ layer and was remained $S_3$ layer and compound middle lamella. Second, the cell wall was slightly degraded and cracked in secondary wall. A gradual thinning of cell wall was occured. The compound middle lamella was separated from secondary wall. The resistance of degradation is increased at vessels, parenchyma, and tracheid and wood fiber in the order named. The type of degradation by species could be classified into four types. Overall degradation type; the degradation of cell wall is usually heavy and the extent of degradation Varies by part of the same sample. Partial degradation type ; this type shows severely different decay type by part of the sample. Nondegraded cells were mixed with degraded cells on the same sample. Erose degradation type ; thinning of the cell wall was occoured and the degradation type was different by part. Slight degradation types ; secondary wall was slightly degraded, cracked and separated from compound middle lamella. Considering different type of burial environment, dry wood was similiar to sound wood and slightly decayed. Waterlogged and peat burial wood was heavilydecayed. Between species of under the same environment, decay type and extent were diferentiated from each other.

• Journal of the Korean Institute of Rural Architecture
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• v.10 no.1
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• pp.101-109
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• 2008

It is very hard to find out Tongbanga-millhouse installed nearby a streamlet to use water with Tongbanga(a kind of water-mill) to polish cereals by pounding like a visage of its old days. It plays an important part in folkloric, architectural and educational aspects. The purpose of this study is to analyse the architectural features of Tongbanga and millhouse itself so that to find the way how to build and fabricate the materials and frame members. Therefore this study has been focused on the composition principle and fabrication method of Tongbanga-millhouse on the side of architecture. The fabrication methods of its house in accordance with regular sequences are as follows. ${\cdot}$ Firstly the decision of location of Tongbanga-millhouse and Hwak(a big mortar made of stone). ${\cdot}$ Slantly three rafter installation at an angle of $50^{\circ}$ to err on the safe side and then slantly fifteen rafter installation making a circular cone shape. ${\cdot}$ Installation of twigs to be circles from bottom to top. ${\cdot}$ Manifoldly covering of trunks peeling the barks from flax plants. ${\cdot}$ Threefoldly thatching with upside barks of oak trees. ${\cdot}$ Placing woods alike rafter on the bark thatches as a weight not to fly away by wind. ${\cdot}$ Binding woods alike rafter with vines of arrowroots to maintain the proper place. The decayed Tongbanga-millhouse by means of upper ways was restored out of all recognition.

• Journal of Korean Society of Forest Science
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• v.79 no.4
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• pp.419-423
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• 1990

This study was carried out to investigate the cause of pith-damaged wood formation, the state of growth, and difference of chemical composition of Japanese Larix(L. leptolepis Gorden). 1. Larix grew normaly to 10 years, and the volume increment was 32.4%. But it was gradually decreased to 19.4% from 11 to 13 years that the heartwood damage was occurred. Therefore, the volume increment was decreased 13%. The decayed wood was formed from fire wound portion of bark by forest fire. The volume loss from pith-dagmaged wood occurred by forest fire was more than 20%. 2. On the ash content, heartwood(0.05%) and pith-damaged wood(0.08%) was lower than sapwood(0.29%). The difference of extractive contents are considered the reason. It is considered that this ash content difference is depend upon the extractive contents among sap, heart and decayed wood parts. Holocellulose contents were from 54.3% to 59.3% and there were no difference among heartwood, pith-damaged wood, and sapwood, On the pentosan contents, heartwood(6.3%) and pith-damaged wood(6.6%) were higher than sapwood. Lignin contents of pith-damaged wood was tower than heartwood (34.4%). This seems to weaken all kinds of wood strength.