• Journal of the Korean Wood Science and Technology
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• v.39 no.3
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• pp.213-220
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• 2011

The objective of this study is to conduct the species identification and tree-ring dating for the wood elements of Daesungjeon (main hall) in Jipyeong Hyanggyo, a Confucian shrine in Jije-myeon, Yangpyeong-gun, Gyeonggi-do, Korea. Major wood species for Daesung Hall was Pinus densiflora (88%) belonging to hard pine. The other species was P. koraiensis belonging to soft pine. One large beam and one collar beam with bark were dated to A.D. 1718 and 1720, suggesting either a large-scale repair or moving in 1720s as the record of an historical document 'Hakgyodeongrok'.

• Journal of Forest and Environmental Science
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• v.40 no.1
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• pp.64-71
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• 2024

Mushroom is very important to rural dwellers due to the various economic, health and nutritional benefits that can be derived from its consumption, sales and utilization. Hence, this experiment was carried out with a view to evaluating the influence of locally available substrate i.e., sawdust of different wood species on the cultivation of Pleurotus ostreatus (oyster mushroom). Pleurotus ostreatus was grown on sawdust (indigenous and exotic species) using two pretreatment methods, which included hot water treatment to remove (a water-soluble extract) and non-extracted sawdusts (substrate). The result of this study showed that there was a significant difference in the effect of different wood species selected. Parkia biglobosa produced a better yield (71.06 g), followed by Anogeissus leiocarpus (53.17 g) and Gmelina arborea (51.39 g) in a non-treated unextracted states. In the treated samples, Parkia biglobosa has the highest yield (50.61 g) followed by Anogeissus leiocarpus (49.28 g) and Gmelina arborea (45.00 g). Thus, Parkia biglobosa and Anogeissus leiocarpus produced a higher yield of mushroom either in a treated or non-treated state and they could be recommended for growing oyster mushroom (Pleurotus ostreatus).

• Journal of the Korean Wood Science and Technology
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• v.31 no.6
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• pp.55-59
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• 2003

The fixation and leaching characteristics of chromated copper arsenate (CCA Type C) and chromium- copper-fluoride-zinc (CCFZ) in domestic softwood (Japanese red pine, Korean pine, and Japanese larch) sapwood were investigated using the expressate method to follow chromium fixation and the American Wood-Preservers' Association (AWPA) leaching procedure to determine leaching properties after fixation. The rates of fixation were affected by preservative types; CCA was fixed much faster than CCFZ for all species evaluated. There were definite differences in the fixation rates of different species, with Korean pine requiring shorter to fix than the other species evaluated. Chromium fixation was greatly enhanced by elevated temperatures, and fixation time can be estimated according to fixation temperatures applied. The percentage of arsenic and zinc leached from domestic softwoods was relatively high compared to chromium and copper, indicating that there is still a relatively high unfixed arsenic and zinc components after complete chromium fixation in CCA-and CCFZ-treated samples, respectively.

• Journal of the Korean Wood Science and Technology
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• v.19 no.4
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• pp.52-61
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• 1991

In this paper, the difference of the property of absorption and desorption for five species in semi-steady state are studied. The species used are listed in Table 1 and the dimension of specimen was $8\times8{\times}T$(Tangential direction)cm and tested in various conditions. A change of average moisture content with time were measured in each cycles. The results obtained are summarized as follows. When the relative humidity in air was maximum or minimum, the distribution of moisture In wood of all specimens were illustrated by exponential curves of decrease or increased from lace 10 center of wood. From the consideration of coefficient of decrease(C), the amount of moisture change of spruce was larger than the others. The pheonomenon was considered no relation to the specific gravity in air dry, but the wood structures. The velocity of the absorption and desorption for species decreased in the order spruce(Picea sitchensis) neodobam(Fagus crenata), solsong(Tsuga heterophylla), meranti(Shorea sp.) and kaesoo(Cercidiphyllum japoicum). In case of constant temperature and water vapor pressure is changed. the amount of absorbed moisture was larger than that of constant water vapor pressure and temperature vaned. In this fact, it is considered that the property of sorption of wood is strongly influenced by vapor pressure gradient than temperature gradient.

• Journal of the Korean Wood Science and Technology
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• v.45 no.2
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• pp.202-212
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• 2017

This study was to establish the interrelation between chemical compositions and near infrared (NIR) spectra for the classification on distinguishability of domestic gymnosperms. Traditional wet chemistry methods and infrared spectral analyses were performed. In chemical compositions of five softwood species including larch (Larix kaempferi), red pine (Pinus densiflora), Korean pine (Pinus koraiensis), cypress (Chamaecyparis obtusa), and cedar (Cryptomeria japonica), their extractives and lignin contents provided the major information for distinction between the wood species. However, depending on the production region and purchasing time of woods, chemical compositions were different even though in same species. Especially, red pine harvested from Naju showed the highest extractive content about 16.3%, whereas that from Donghae showed about 5.0%. These results were expected due to different environmental conditions such as sunshine amount, nutrients and moisture contents, and these phenomena were also observed in other species. As a result of the principal component analysis (PCA) using NIR between five species (total 19 samples), the samples were divided into three groups in the score plot based on principal component (PC) 1 and principal component (PC) 2; group 1) red pine and Korean pine, group 2) larch, and group 3) cypress and cedar. Based on the chemical composition results, it was concluded that extractive content was highly relevant to wood classification by NIR analysis.

• Journal of Conservation Science
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• v.35 no.6
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• pp.670-680
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• 2019

This study attempts to identify whether there were preferred wood species or any required properties depending on the use of wooden objects by comparing wood species analysis results of wooden objects, which are classified specifically by their uses like comb, wooden tablets, containers, etc., excavated from Haman Seongsansansung mountain fortress, which is the archaeological site of the Three Kingdoms era and those excavated from archaeological sites in Gyeongsang province considered to be the similar era of Haman Seongsansansung mountain fortress site. Wooden tablets and combs show the preferred species clearly and containers preferred wood species with the mid-ranged strength and the resistance against moisture migration.

• Journal of the Korean Wood Science and Technology
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• v.52 no.4
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• pp.301-318
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• 2024

Contrary to other materials like metals, glass, etc., wood continuously interacts with the environment, increasing and decreasing its moisture content according to the humidity of the air and changing its dimensions by swelling or shrinking. Water diffusion through laminated solid wood is crucial in wood bonding processes. The adhesive layer might block the diffusion if the water vapor diffusion is perpendicular to the bond line. As a result of this blockage, different proportions of deformation appear on the two sides of the bond line, which causes stresses in the bonded assembly. The question arises of how long the bonded structure will keep its integrity due to moisture diffusion blockage, inevitable tensions appearing in the glue line, and how these stresses could be avoided. With cross laminated timber (CLT) solid wood panel production, this question gains new importance. Despite the relevance, only a limited number of publications are available. Comprehensive research would also be necessary considering both the molecular structure and diffusion properties of the adhesive adjusted to the wood species (covering possible substituting wood species, too). Overall, this review serves as a resource for enhancing our understanding of water vapor diffusion through wood adhesive layers and provides insights that have implications for reducing stresses in bonded wood assemblies and the performance of the bonded group over time. Furthermore, identifying knowledge gaps is necessary to establish the basis for investigating the diffusion property of CLT panels.

• Journal of the Korean Wood Science and Technology
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• v.52 no.1
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• pp.70-86
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• 2024

Termites are a serious threat to wood-based products in Indonesia. This study investigated the termite resistant property of glulam made from polystyrene-modified wood. Three tropical fast-growing wood species, namely mangium (Acacia mangium), manii (Maesopsis eminii), and rubberwood (Hevea brasiliensis), were prepared for flat-sawn laminae. After getting air-dried condition, the laminae were impregnated with polystyrene using potassium peroxydisulphate as a catalyst followed by polymerization at 80℃. Polystyrene-impregnated and control glued-laminated lumbers (glulams) were manufactured, and solid wood was provided. Three wood species and three wood products with six replicates were exposed in a field in Bogor, Indonesia, for four months, and before the tests, their density and moisture content were measured. At the end of the field tests, the weight loss and protection levels of each test sample were determined. A completely randomized factorial design was used for data analysis. The weight percentage gains for mangium, manii, and rubberwood were 22.30%, 18.22%, and 10.44%, respectively. The results showed that manii belonged to low-density wood, whereas the other two woods were medium-density wood, and the moisture content was the ambient moisture content, typical of the Bogor area. Regarding weight loss and protection level, mangium was the most durable against subterranean termite attacks, followed by rubberwood and manii. Among the wood products, the polystyrene-impregnated glulam presented the highest durability, followed by the control glulam and solid wood. Therefore, mangium and rubberwood polystyrene-impregnated glulams are recommended for future product development.

• Mycobiology
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• v.37 no.2
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• pp.147-151
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• 2009

The wood-rotting fungi of three Korean islands in the Yellow Sea, Soyeonpyung-do (SY), Oeyeon-do (OY), and Gageo-do (GG), were investigated from October 2004 to November 2005. During four sampling trips on each island, a total of 46, 44, and 44 specimens were collected from SY, OY, and GG, respectively. The identified wood-rotting fungi from SY included 29 species of 22 genera and nine families; OY had 31 species of 26 genera and 10 families; and GG had 34 species of 27 genera and 11 families. The majority of the fungi were in the Polyporaceae, which was represented by 23 genera and 30 species. Auricularia polytricha, Daedaleopsis tricolor, Daldinia concentrica, Hymenochaete cinnamomea, Hymenochaete yasudai, Hyphoderma setigerum, Lopharia mirabilis, Schizopora paradoxa, and Trametes versicolor were collected from all three islands.

• Journal of the Korean Wood Science and Technology
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• v.14 no.4
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• pp.40-46
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• 1986

Change of color of woods is a trouble frequently found in decorative wood products. In this paper, studies were carried out on discoloation sensitivities of wood specimens to iron (0.1%, $FeCl_3{\cdot}6H_2O$), alkali (pH12.0, NaOH), acid (pH 1.0 $C_2H_2O_4$) and exposing to sunlight (40 hrs.). Four soft-woods and eleven hard-woods grown in Korea were used in this test. The results obtained were as follows: 1. In iron stain, strong discolored wood species were Larix leptolepis, Quercus mongolica. Zelkova serrata and Prunus yedoensis, and light discolored were Paulownia lomentosa and Pinus rigida. 2. In alkali stain. light discolored wood species were Abies holophylla, Kalopanax pictum, Populus ${\times}$ albaglandulosa, Acer mono, Pinus rigida, Pinus densiflora, Quercus mongolica, Betula platyphylla var. japonica, Prunus yedoensis, Zelkova serrata, Populus euramericana, Pinus koraiensis and Paulownia tomentosa, but there was no wood species of strong discolored compared with the color difference values of other reports. 3. In acid stain, light discolored wood species were Pinus rigida, Paulownia tomentosa. Pinus koraiensis, Quercus mongolica, Kalopanax piclum and Acer mone, but there was no strong discolored species compared with the color difference values of other reports. 4. In exposing to sunlight, strong discolored species were Larix leptolepis, Acer mono, Paulownia tomentosa, Populus euramericana, Pinus densijlora, Robinia pseudoacacia, Abies holophylla, Populus ${\times}$ albaglandulosa, Zelkova serrata, Prunus yedoensis and Pinus rigida, and light discolored was Alnus japonica. In general, it was shown that Korean wood species were susceptible to change of color by exposing to sunlight and iron stain compared with by alkali stain and acid stain.