• Journal of the Korean Wood Science and Technology
• /
• v.43 no.2
• /
• pp.196-205
• /
• 2015

The aim of this study was to evaluate the fuel characteristics of thermally treated wood chips of the Larix kaempferi C. As torrefaction temperature was increased ($200^{\circ}C$ to $300^{\circ}C$), the carbon content, calorific value, and mass loss of torrefied wood chips increased significantly. The torrefied wood chips were shown to have hydrophobic properties even when only treated by mild torrefaction. The energy required to grind torrefied wood chips was reduced by the torrefaction process. Different sizes of wood chips were used in this study; however, this produced almost no difference in the fuel characteristics of processed Larix kaempferi C, except in the distribution of ground wood particles. Similar results were observed when the wood chips were torrefied for different lengths of time (15 min to 60 min) at a constant temperature. Torrefaction was shown to have positive effects on the fuel characteristics of Larix kaempferi C, including improved energy density, storage, and grindability.

• Korean Journal of Medicinal Crop Science
• /
• v.20 no.6
• /
• pp.440-446
• /
• 2012

Gastrodia elata, an achlorophyllous orchid plant, is rare medicinal plant. We investigated the genetic diversity in G. elata from 4 locations by using Inter-Simple Sequence Repeats (ISSR) markers. Shannon's information Index (S.I.) indicating genetic diversity ranged from 0.255 (Pocheon) to 0.322 (Muju) with the mean of 0.29. The level of genetic diversity was lower than other plant and most genetic diversity was allocated among individuals within populations (26.81%). The UPGMA dendrogram based on genetic distance failed in showing decisive geographic relationship. In the case of gastrodin (GA), the major components in G. elata, Sangju was highest. The ergothionine (ERG) was detected a lot of contents in Muju and Pocheon. In conclusion, our results is very important information for explaining relationship of genetic variation and functional substances without the effects of environment factors and developing genetic marker by ISSR in G. elata, which may be responsible for the development of breeds with a lot of functional substance in G. elata.

• Journal of Korean Society of Forest Science
• /
• v.95 no.5
• /
• pp.516-523
• /
• 2006

Marginal soils such as BRlS (Beach Ridges Interspersed with Swales) soils and ex-tin mining land make up approximately 0.5 million ha or about 2% of Malaysia's land area. In the coastal areas of the east coast of Peninsular Malaysia impoverished sandy BRIS dominates the landscape with most lying idle as there is no national management plan for their utilization. A field study was carried out to see whether mycorrhizal application had any effect on the growth of three exotic Acacia spp., i.e. Acacia auriculiformis, A. mangium and Acacia hybrid (A. auriculiformis ${\times}$ A. mangium) on BRIS soils. Two types of mycorrhizal inoculum, namely, a commercially available arbuscular mycorrhizal inoculum marketed as $MycoGold^{TM}$ and an indigenous ectomycorrhizal Tomentella sp. inoculum were tested. In the initial six months, height growth of all three tree species inoculated with the arbuscular mycorrhizal inoculum was significantly improved compared to the ectomycorrhizal inoculated and uninoculated control plants. The mycorrhizal effect was not evident thereafter and repeated application of the arbuscular mycorrhizal inoculum may be necessary for continued growth enhancement. Of the three species, A. mangium had the highest relative height growth rate over the 24 months on BRlS soils.

• Journal of Environmental Science International
• /
• v.32 no.1
• /
• pp.25-35
• /
• 2023

The purpose of this study was to determine the optimal sound absorption conditions by comparing the sound absorption characteristics of fresh and air-dried leaves of Quercus glauca, the main species of evergreen broadleaf trees (EBLT) in southern Korea. The sound absorption coefficients (SACs) obtained under 18 conditions were comparatively analyzed. The SAC of air-dried leaves improved significantly with increasing leaf layer thickness. The highest average SAC in the fresh leaf group was 0.617, which was observed under the condition of a leaf specimen size of 0.5 × 0.5 cm² and a leaf layer thickness of 1.75 cm. In a group of air-dried leaves, this was 0.615 under the condition of a leaf specimen size of 0.5 × 0.5 cm² and a leaf layer thickness of 2.50 cm. The maximum value of SAC for each wavelength was observed under the condition of a leaf layer thickness of 2.50 cm consisting of 0.5 × 0.5 cm² leaf specimens, ranging from 1,400 Hz to 1,500 Hz.

• Journal of the Korean Wood Science and Technology
• /
• v.51 no.6
• /
• pp.509-525
• /
• 2023

This study has delved into the evolution of Hanji-manufacturing molds and techniques from ancient times to the present, aiming to uncover the current state of traditional Hanji-making techniques. In the absence of records on Hanji-making, various ancient documents, rare books, and documents during the Japanese occupation period, among other artifacts and relics, were analyzed in this study. It was discovered that a sudden significant transformation occurred in the Hanji field during the Japanese occupation period. Soda ash and caustic soda were commonly used for the pretreatment of White bark. Furthermore, a chemical bleaching powder was introduced for the pretreated White bark. Additionally, manual beating of the bark was replaced by mechanical beating methods. While these changes brought convenience to papermakers, they also resulted in a deterioration of Hanji quality. Furthermore, it was revealed that the term "Hanji" has been in use since at least 1908. Furthermore, this study clarified that Heulimtteugi is not the only traditional Hanji-making method in Korea. Instead, there existed Korea's own traditional Gadoomtteugi method, at least up to the 1930s, before the Japanese-style Gadoomtteugi became common in Korea. Additionally, for the first time, this study raises the possibility of the adoption of mold-hanging techniques into Korea's Heulimtteugi method from foreign sources.

• The Plant Pathology Journal
• /
• v.18 no.2
• /
• pp.74-76
• /
• 2002

This study unexpectedly detected a deletion in the promoter region of ras gene in two Korean strains of oak mushrooms, Lentinula edodes (Berk.). Sequencing of the promoter regions revealed that one type consisting of two strains had a 113 bp deletion in the region. The pas promoter region of Korean strains differed by 16 bases from that of the Japanese strains. Between the two types of Korean strains, except for the deleted portion, only a single site appeared to be different.

• Korean Journal of Plant Taxonomy
• /
• v.41 no.3
• /
• pp.249-252
• /
• 2011

Scutellaria tuberifera C. Y. Wu & C. Chen belonging to Lamiaceae, a species previously unrecorded for Korean flora, was collected streamside in the Andeok valley of Seogwipo-Si, on Jeju island. This species can be distinguished from others of Scutellaria from Korea by having rhizomes with leafless and branching stolons at the nodes, globose to ovoid tubers 5-7 mm in diameter at the terminal parts, and stems densely spreading pilose. Photos of the habit and illustration are provided.

• Journal of the Korean Wood Science and Technology
• /
• v.42 no.2
• /
• pp.214-221
• /
• 2014

The deterioration in wood by the brown-rot fungus (Fomitopsispalustris) and the white-rot fungus (Trametesversicolor) were measured using ultrasonic velocity. Those were used for the decay exposure and 4 wood species of wood as the test specimens, Pinusdensiflora, Larixkaempferi, Pinuskoraiensis and Pinusrigida, were chosen with both the brown- and white-rot culture petridish during 12 weeks. After 12 weeks, the decrease rate of ultrasonic velocity was measured at 10~15%. In both brown- and white-rot exposure experiments, P. rigida showed significant decrease in ultrasonic velocity (20%), L. kaempferi on the other hand did not show decrease in ultrasonic velocity. After the fungal exposure experiment, the inside of specimens was investigated by computer tomography (C/T). After C/T investigation, bending tests were performed.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
• /
• 2017.11a
• /
• pp.84-85
• /
• 2017

• Journal of the Korean Wood Science and Technology
• /
• v.31 no.3
• /
• pp.30-34
• /
• 2003

This study was carried out to investigate the constituents of Platycarya strobilacea (Juglandaceae) wood. To isolate compounds, wood was extracted with ethanol (EtOH) and then partitioned with petroleum ether, diethyl ether (Et₂O) and ethyl acetate (EtOAc) successively. After partitioned, diethyl ether fraction was subjected to column chromatography with various solvent system in silica gel and/or Sephadex LH-20. Structures were elucidated by spectroscopic methods including MS, ¹H, ¹³C and 2D-NMR experiments. Three compounds were isolated from the wood and identified as kaempferol 3-O-𝛼-L-rhamnopyranoside (afzelin, I), quercetin 3-O-𝛼-L-rhamnopyranoside (quercitrin, II), myricetin 3-O-𝛼-L-rhamnopyranoside (myricitrin, III).