• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.36-43
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• 2006

Using fluidized bed type fast pyrolysis system (capacity 400 g/h) bio-oils were produced from beech (Fagus sylvatica) and softwood mixture (spruce and larch, 50:50). The pyrolysis was performed for 1~2 s at the temperature of $470{\pm}5^{\circ}C$. Pyrolysis products consisted of liquid form of bio-oil, char and gases. In beech wood bio-oil was formed to ca. 60% based on dry biomass weight and the yield of bio-oil was 49% in soft wood mixture. The moisture contents in both bio-oils were ranged between 17% and 22% and the bio-oil's density was measured to $1.2kg/{\ell}$. Bio-oils were composed of 45% carbon, 47% oxygen, 7% hydrogen and lower than 1% nitrogen,which was very similar to those of original biomass. In comparison with oils from fossil resources, oxygen content was very high in bio-oils, while no sulfur was found. More than 90 low molecular weight components, classified to aromatic and non aromatic compounds, were identified in bio-oils by gas chromatographic analysis, which amounted to 31~33% based on the dry weight of bio-oils.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.346-357
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• 2013

In this study, it was conducted to produce wood pellets using domestic forest thinning residues and examine their quality according to Korean pellet quality standard. Raw materials were composed of larch and mixed broad leaves species. Based on the small-end diameter (6 cm), they were classified into four different types of raw materials such as LM (larch with middle diameter), LS (larch with small diameter), MM (mixed broadleaf with middle diameter), and MS (mixed broadleaf with small diameter). After crushing and drying process, wood pellets were produced by a ring-die type pelletizer using each raw material. Wood pellets made from four different types of raw materials were tested for their quality such as calorific value, moisture content, ash content, inorganic matters and so on. As results of quality analysis, the calorific values of all wood pellets were higher than 198 kcal/kg, and satisfied with the first grade of Korea wood pellet standard. The ash content was slightly increased after pelletizing. Mechanical durability of wood pellets was highly dependent on the types of raw materials. The quality differences among wood pellets were turned out due to different physical and chemical characteristics of raw materials even though the same pelletizing condition was applied.

• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.350-359
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• 2016

We performed fast pyrolysis of empty fruit bunch (EFB) in the range of temperature from $400{\sim}550^{\circ}C$ and 1.3 s of residence time. The effect of temperature on the yields and physicochemical properties of pyrolytic products were also studied. Elemental and component analysis of EFB showed that the large amount of potassium (ca. 8400 ppm) presents in the feedstock. Thermogravimetric analysis suggested that the potassium in the feedstock catalyzed degradation of cellulose. The yield of bio-oil increased with increasing temperature in the range of temperature from $400{\sim}500^{\circ}C$, while that of gas and biochar decreased and showed monotonous change each with increasing temperature. When the EFB was pyrolyzed at $550^{\circ}C$, the yield of bio-oil and char decreased while that of gas increased. Water content of the bio-oils obtained at different temperatures was 20~30% and their total acid number were less than 100 mg KOH/g oil. Viscosity of the bio-oils was 11 cSt (centistoke), and heating value varied from 15 to 17 MJ/kg. Using GC/MS analysis, 27 chemical compounds which were classified into two groups (cellulose-derived and lignin-derived) were identified. Remarkably the concentration of phenol was approximately 25% based on entire chemical compounds.

• Journal of Plant Biotechnology
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• v.35 no.1
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• pp.63-68
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• 2008

Single-node stem pieces ca. 1 cm in length containing a axillary bud were obtained from in vitro plants of potato (Solanum tuberosum L.). The influences by a position of the node and the existence of a leaf at the node were observed in the single-node culture on the 8% sucrose MS medium. The effect of CCC was also investigated for the microtuberization. The apical part node was excellent in the tuberization not to mention shoot length, fresh weight, diameter, the number of node on the in vitro culture of a single-node than the lower part. The differences in the diameter of a tuber formed in the part of the axillary bud on all treatments including the cultivation of the apical part node were not recognized. However, the fresh weight of the tuber showed high value in the tuber formed at the axillary bud of shoot apex part. At 20 days after cultivation, tuberization was promoted in the new stolen that developed from the bud of node with a leaf under SD condition of 8 hours at $20^{\circ}C$. The tuberization from axillary bud of the single-node without leaf was inhibited at high temperature of $28^{\circ}C$ regardless of daylength. Whereas, tuberization at $20^{\circ}C$ and $28^{\circ}C$ was similar without the difference under SD condition but the tuber formation ratio were low. CCC 500 mg/L promoted tuberization and the effect was also showed even under LD condition at $28^{\circ}C$. The inhibiton of tuberization under LD and high temperature condition could be solved by treatment with CCC.

• Food Science and Preservation
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• v.12 no.2
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• pp.161-165
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• 2005

The content of general components such as moisture, crude ash, protein and crude fat were not different among the samples, but the content of crude protein in the fresh garlic was higher (in fresh garlic) than that of heat-treated garlic. Eighteen amino acids were analysed from the fresh garlic. The content of arginine was the highest in the fresh garlic. The amount of free amino acids was less than that of total amino acids, but their compositions were similar. Among minerals, the content of K was much higher than those of Mg, Ca and Na. The volatile compounds from the garlic extracts were identified by GC/MS. The composition of diallyl disulfides was very high among the volatile compounds, which were decreased in heat-treated ones.

• Journal of Biosystems Engineering
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• v.22 no.4
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• pp.469-478
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• 1997

This study was conducted to develop an automatic nutrient-solution mixing system for small-scale sewers. The nutrient-solution mixing system consisted of a low-cost and precise metering device and data acquisition ＆ control system with a personal computer. and, the metering device was composed of three parts those were supply pumps, metering cylinders and venturi tube. The system controlled electric conductivity(EC) and pH of nutrient-solution based on the time-based feedback control method with the information about temperature, EC, and pH of the nutrient-solution. The performance of the nutrient-solution mixing system was evaluated through the control of EC and pH while compared with those of commercial system. Also an experimental cultivation of tomato was conducted to verify and to improve the developed system. Results of this study were as follows. 1. The correlation coefficient of meteing device between the flow rate and operating time was 0.9999, and the linear reuession equation computed was y=21.759x, where y is the discharge($g$) and x is the operating time(s). 2. Calculated errors for the developed metering device and two commercial pump were $\pm$0.3% $\pm$2.45% and $\pm$1.38 % FS error respectively. 3. An automatic nutrient-solution mixing system based on a low-cost and precise metering device was developed. 4. The full scale errors of the developed system in controlling EC and pH at 23$\pm$1$^{\circ}C$ were $\pm$0.05mS/cm and $\pm$0.2, respectively 5. When using the commercial system, the controlled values of EC and pH of the 500 $\ell$ of water were 1.29 mS/cm and 6.1 pH for the setting points of 1.4 mS/cm and 6.0 pH respectively at 23$pm1^{\circ}C$. 6. The developed nutrient-solution control system showed $\pm$0.05 ms/cm of deviation from the setting EC value over the experimental cultivation period. 7. The deviation from the average values of Ca and Mg mass content in the several nutrient-solution were 0.5% and 1.8% respectively.

• The Korean Journal of Pharmacology
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• v.32 no.2
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• pp.127-138
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• 1996

The effects of adenosine analogues on the electrically-evoked acetylcholine(ACh) release and the influence of ischemia on the effects were studied in the rat hippocampus. Slices from the rat hippocampus were equilibrated with $0.1{\mu}M$ $[^3H]-choline$ and the release of the labelled product, $[^3H]-ACh$, was evoked by electrical stimulation(3 Hz, 2 ms, 5 $VCm^{-1}$ and rectangular pulses for 2 min), and the influence of various agents on the evoked tritiumoutflow was investigated. Ischemia(10 min with 95% $N_2$ + 5% $CO_2$) increased both the basal and evoked ACh release. These increases were abolished by glucose addition into the superfused medium, and they significantly inhibited either by 0.1 & $0.3{\mu}M$ TTX pretreatment or by removing $Ca^{++}$ in the medium. MK-801($1{\sim}10{\mu}M$), a specific NMDA receptor antagonist, and glibenclamide $(1{\mu}M)$, a $K^+-channel$ inhibitor, did not alter the evoked ACh release and nor did they affect the ischemia-induced increases In ACh release. However, polymyxin B(0.03 mg), a specific protein kinase C inhibitor, significantly inhibited the effects of ischemia on the evoked ACh release. Adenosine and $N^6-cyclopentyladenosine$ decreased the ACh release in a dose dependent manner in ischemic condition, though the magnitude of inhibition was far less than those in normal(normoxic) condition. However, the treatment with $5{\mu}M$ DPCPX, a potent $A_1-adenosine$ receptor antagonist, potentiated the ischemia-effect. These results indicate that the evoked-ACh release is potentiated by ischemia, and this process being most probably mediated by protein kinase C, and that the decreased effect of ACh release mediated by $A_1-adenosine$ receptor is significantly inhibited in ischemic state.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.1-6
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• 2003

Chemical compositions of several herbs (rosemary, mint, thyme, sage, and lavender) cultivated in Korea were analyzed. Approximate compositions were as follows: moisture $69.92{\sim}82.10%$, crude ash $2.48{\sim}6.15%$, crude fat $0.40{\sim}2.46%$, crude protein $0.84{\sim}1.57%$, and crude fiber $2.48{\sim}6.15%$. Total contents of phenolics determined by Folin-Dennis's method were in the range of $73.24{\sim}197.79mg%$. Contents of minerals, Na, Ca, Mn, P, Mg, Zn, and Fe determined by ICP-AES were $43.0{\sim}112.5,\;177.5{\sim}304.0,\;0.5{\sim}1.5,\;74.0{\sim}218.5,\;57.0{\sim}116.0,\;1.0{\sim}2.0$ and $3.0{\sim}5.0mg%$, respectively. Free sugar contents determined by HPLC were: sucrose $0{\sim}7.61$, glucose $0.94{\sim}15.92$, and rhamnose $0.64{\sim}7.99mg%$. Fatty acids including palmitic, stearic, oleic, linoleic, linolenic, and arachidonic acids were identified by GC. Linoleic and linolenic acid contents were higher than those of palmitic and stearic acids. Aroma components identified by GC-MS were 1,8-cineole, ${\alpha}-phellandrene,\;{\alpha}-terpinene,\;{\beta}-pinene,\;{\beta}-thujone$, borneol, butan-1-ol, cis-sabinene hydrate, ${\delta}-carene,\;{\gamma}-terpinene$, and verbenone.

• Korean Journal of Agricultural Science
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• v.13 no.2
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• pp.157-167
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• 1986

The study was carried out to identify several factors affecting isolation and culture of cotyledone and leaf mesophyll protoplasts of cabbage (Brassica oleraceae), petsai (B.campestris subsp. pekinensis) and rape (B.napus). High viable protoplasts could be obtained when the cotyledon and the leaf mesophyll tissue of all species were treated with enzyme solution composed of 1% macerozyme 'R-10', 1.5% Onozuka 'R-10', 10% mannitol and 50,0 mM $CaCl_22H_2O$ for 4 hours. The protoplasts which obtained from the cotyledon of all species except the cabbage and the leaf mesophyll tissue of all species were divided on NN culture medium supplemented with 9.1% mannitol, 1% glucose, 1% sucrose, $1mg/{\ell}$ 2,4-D, $0.5mg/{\ell}$ NAA and $0.5mg/{\ell}$ BA. The division of the rape leaf mesophyll protoplasts were continued and led to colony.

• Korean Journal of Microbiology
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• v.52 no.1
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• pp.32-39
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• 2016

Coastal plant species Tetragonia tetragonoides (Pall.) Kuntze native to the Dokdo islands was sampled and then 17 endophytic fungi were purely isolated based on morphological differences. The fungal isolates were characterized by their growth properties under NaCl concentration or pH gradient. Culture filtrates of the 17 fungal isolates were treated to Waito-c rice (WR) seedlings for verifying plant growth-promoting activity. As the results, YH103 strain showed the highest plant growth-promoting activity among them. Phylogenetic analysis of the isolates was done by the maximum likelihood method based on partial internal transcribed spacer region (ITS region: contaning ITS1, 5.8S, and ITS2), beta-tubulin (BenA), and calmodulin (CaM) gene sequences. Chromatographic analysis of the strain YH103 culture filtrate showed the existence of gibberellins ($GA_4$, $GA_7$, $GA_8$, and $GA_{19}$). Finally, the strain YH103 was identified as Aspergillus tubingensis by microscopic observation and molecular analysis and, to our knowledge, this is the first report of GAs producing A. tubingensis.