• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.54-59
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• 1995

This experiment was carried out to evaluate the role of oxalic acid metabolism in the incipient decay of brown rotting, and to investigate the effects of various compositions of culture medium. Until 5days incubation, the amount of oxalic acid produced by Tyromyces palustris was increased, while pH was gradually decreased. The difference in oxalic acid production depending on carbon sources was not significant and the pH adjustment of media did not stimulate the production of oxalic acid. In this experiment, hemicellulose was hydrolyzed with 1% oxalic acid, so it is suggested that nonenzymatic acid hydrolysis of hemicelluloses might be involved in the process of incipient decay of brown-rot fungi.

• Korean Journal of Materials Research
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• v.17 no.7
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• pp.371-375
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• 2007

In-situ observation of electromigration behavior of eutectic SnPb solder was performed as a function of line length at $100^{\circ}C$, $6{\times}10^4A/cm$ condition in a scanning electron microscope chamber. The incubation time for edge drift and the edge drift velocity increase as line length increases, which are discussed with the void nucleation stage of solder bump and the electromigration back flux force, respectively. Finally, the existence of electromigration product (jL) and its line length dependency are also discussed.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.598-602
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• 1998

Twenty two rhizobacteria were isolated from the roots and rhizosphere of radish, carnation, potato and tomato. There isolates produced a fluorescent pigment in King's B medium and identified as Pseudomonas spp. These isolates colonized roots and rhizosphere of the host plants. In the study of cultural characteristics of the bacteria, the pH of the culture broth was changed from neutral (7.0) to alkali (8.8∼9.41) and the numbers of cells were increased from 106 to 108 after 40 hr of incubation in basal standard succinate medium. The salicylic acid production identified by pink color reaction were observed in 7 bacteria. Out of these 7 salicylic acid producing bacteria, only 2 strains of bacteria such as Pseudomonas fluorescens RS006, and Pseudomonas sp. EN401 were confirmed as salicylic acid producers by optical density measurement. Therefore, for screening of salicylic acid producing bacteria from the roots and rhizosphere, color reaction of the culture medium should be done in the first step, and then optical density measurement of culture extract should be made for the confirmation of salicylic acid production.

• The Korean Journal of Mycology
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• v.13 no.2
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• pp.111-114
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• 1985

The production of lac case by the funguson various media was studied. The characteristics of the enzyme were also studied regarding to the optimum pH, stability, Km value, and inactivation. The maximum activity of laccase reached the 40 days of incubation and the barley straw extract appeared to be a strong inducer for laccase. The enzyme showed stability at wide range of pH with optimum pH of 6.6. Temperature stability of the enzyme was high. Laccase was not inactivated by the organic solvents used for the precipitation. The enzyme, how­ever, was completely inactivated by trichloroacetic acid and sodium azide.

• Microbiology and Biotechnology Letters
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• v.21 no.6
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• pp.609-614
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• 1993

The optimum conditions for the submerged mycelial culture of Lentinus edodes SR-1 were elucidated to be incubation temperature of 25C, initial pH 4.0, agitation of 300 rpm, inoculation of 10.0%(v/v), and aeration of 1.0 v/v/m in TGY medium. The optimum c/n ratio and economic yield coeffcient for the submerged mycelial culture were 13.1:1 and 0.45 respectively. As the plant growth hormones test, SCM medium containing 0.5ppm of 2,4-dicholorophenoxyacetic acid increased mycelial yield in 1.1%, but 6-benzylaminopurine was not effective.

• Mycobiology
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• v.39 no.3
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• pp.230-232
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• 2011

In this study, we characterized sporadically occurring sclerotium rot caused by Sclerotium rolfsii in Chinese chive (Allium tuberosum Roth.) in farm fields in Sacheon, Korea. The initial symptom of the disease was water-soaked, which progressed to rotting, wilting, blighting, and eventually death. Further, mycelial mats spread over the lesions near the soil line, and sclerotia formed on the scaly stem and leaves. The sclerotia were globoid, 1~3 mm, and white to brown. The optimum temperature for growth and sclerotia formation on potato dextrose agar (PDA) was $30^{\circ}C$. The diameter of the hypae ranged from 4 to 8 ${\mu}m$. Clamp connection was observed on PDA medium after 5 days of incubation. Based on the mycological characteristics, internal transcribed spacer sequence analysis, and pathogenicity test, the causal agent was identified as Sclerotium rolfsii Saccardo. This is the first report of sclerotium rot in Chinese chive caused by S. rolfsii in Korea.

• The Korean Journal of Ecology
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• v.21 no.6
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• pp.751-757
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• 1998

Nitrogen dynamics in mineral soils of an alder (Alnus maximowiczii) stand established on volcano Mt. Showa-Shinzan were measured by laboratory incubation method in order to clarify characteristics of $NH_{4}^{+}$ mineralization and nitrification rate, from August 1994 to July 196. Contents of total N and organic matter were relatively low, but increased in May-July. Extractable $NH_{4}^{+}$ concentrations and $NH_{4}^{+}$ mineralization were high in June and July, and decreased in midsummer and fall. Extractable $NO_{3}^{-}$ concentrations did not vary seasonally. Negative values at $NH_{4}^{+}$ mineralization and nitrification rate were observed in August and September. $NH_{4}^{+}$ mineralization was positively correlated with soil organic matter, and nitrification rates were influenced by extractable $NH_{4}^{+}$ concentration and $NH_{4}^{+}$ mineralization.

• The Korean Journal of Mycology
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• v.46 no.1
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• pp.28-33
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• 2018

A fungal isolate designated KNU16-033 was isolated from a soil sample in Daegu, Korea. White, short, and felt-like aerial mycelia appeared on the surface of colonies of the isolate. Colonies with a smooth texture developed slowly and reached a diameter of 78 mm after 21 days of incubation on potato dextrose agar. This isolate displayed globose, colorless or light yellow sporangiospores, which differed morphologically from the sporangiospores of Gongronella butleri, which were hyaline, oval to flattened on one side or almost reniform. Based on these morphological characteristics and phylogenetic analysis using internal transcribed spacer regions, the isolated fungus was identified as G. guangdongensis belonging to Cunninghamellaceae. To our knowledge, this is the first record of G. guangdongensis in Korea.

• Applied Science and Convergence Technology
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• v.23 no.1
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• pp.40-43
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• 2014

We investigated the growth characteristics and interfacial properties of $HfO_2$ films deposited on Ge substrate through atomic layer deposited (ALD) by using an in-situ medium energy ion scattering analysis. The growth kinetics of $HfO_2$ grown on a $GeO_2/Ge$ substrate through ALD is similar to that grown on an $SiO_2/Si$ substrate. However, the incubation period of $HfO_2$ deposition on Ge is shorter than that on Si. The $HfO_2$ grown on the GeO/Ge substrate shows a significant diffusion of Hf atoms into the substrate interface and GeO volatilization after annealing at $700^{\circ}C$. The presence of low-quality Ge oxide or suboxide may degrade the electrical performance of device.

• Journal of Life Science
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• v.10 no.1
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• pp.94-100
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• 2000

Urease is an important microbial enzyme and its production is a marker to predict potential pathogenicity. An unusual halophilic bacterium producing urease was isolated from sea product and identified as Vibrio parahaemolyticus KH410. Its biochemical properties were indole negative, gelatin positive, sodium citrate positive and Kanagawa positive whereas other characteristics were identical as the standard strain except it showed a positive reaction on Christensen's urea agar. V. parahaemolyticus urease production was directly related to urea concentration. The production of urease was noticeable by the addition of 0.2% urea, 0.5% glucose, 2% NaCl in LB broth, and the initial pH of 5.5. The maximum production reached after 6 hr of incubation at 37$^{\circ}C$. However, NiCl2, metal ions, phosphorus did not affect production of urease.