• Journal of Aquaculture
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• v.3 no.1
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• pp.65-77
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• 1990

The growth of ark shell, Anadara broughtonii was compared between two areas, $Gad\v{o}gdo$ in Jinhae Bay and Namhae located in the southern coast of Korea from May 1986 to October 1987. The ark shells in Namhae grew from 1.38$\pm$0.32 em to 7.20$\pm$0.30 em in shell length, while those in $Gad\v{o}gdo$ grew from 1.38$\pm$0.32 em to 6,41$\pm$0.30 cm in 17 months. Shell height, shell breadth and total weigth of the ark shells in Namhae were also greater than those from $Gad\v{o}gdo$. Bottom quality of $Gad\v{o}gdo$ showed negative skewness, and that of Namhae was positive skewness. Negative skewness of $Gad\v{o}gdo$ seems to be caused by the effect of strong tidal current. This may indicate that Namhae is better area than $Gad\v{o}gdo$ for the culture of the ark shell.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.211-218
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• 1982

The specific heat capacity and density of soybean oil and soy protein composing of the soybean curd were measured between $30^{\circ}C\;and\;-40^{\circ}C$. The thermal conductivity of soybean oil was measured to be 0.160 and 0.140, $W/m{\cdot}K$ at unfrozen and frozen states, respectively. The effective thermal conductivity of the soybean curd depended not only on its water content but also on its fat and protein contents.

• Korean Journal of Materials Research
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• v.30 no.1
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• pp.50-50
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• 2020

• Resources Recycling
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• v.30 no.4
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• pp.64-74
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• 2021

The importance of uranium metal is growing day by day in light of its increasing global demand for fulfilling societal needs through atomic power programs. Considering the high demand for uranium, it is necessary to find innovative hydrometallurgical techniques to separate uranium from other associated elements, especially vanadium. This study deals with the separation of uranium(VI) and vanadium(V) from sulfuric acid solutions using commercial amine-based extractants diluted in kerosene. The concentrations of the sulfuric acid solutions ranged from 0.005 to 5.0 mol/L. The effect of extractant concentration ranging from 0.005 to 0.2 mol/L was studied. The temperature was maintained at 25℃ and the experiment was performed for 30 min at an aqueous: organic phase ratio of 1 (A:O = 1:1). The calculated separation factors (SFs) are presented and comparisons are made among all the experiments.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.376-382
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• 1990

An extracellular cellulase producing bacterium YE-5 was isolated from soil, and identified as a Cellulomonas sp. by its taxonomical characteristics. The maximal activities of avicelase (0.35 units/ml), CMCase (3.18 units/ml), FPase (0.315 units/ml) and $\beta$-glucosidase (0.882 units/ml) were obtained when this strain was cultured for 48 hrs at $30^{\circ}C$ in a medium containing 0.8% (w/v) Solka floc, 0.06010 (wlv) urea, 0.1% (w/v) $K_2HP0_4$, 0.1% (w/v) $MgS0_4.7H2_0$, 0.2% (w/v) bacto peptone, 0.2% (w/v) yeast extract and pH 6.5. The cellulase was purified by ammonium sulfate fractionation, DEAE-Sepharose column chromatography and Sephadex 6-100 column chromatography from culture filtrate of Cellulomonus sp. YE-5. The molecular weights of purified avieelase, CMCase I, and CMCase II were estimated to be about 95,000 ~ 105,000, 46,000 ~ 47,000 and 120,000 ~ 125,000, respectively.

• Archives of Pharmacal Research
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• v.15 no.1
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• pp.30-34
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• 1992

In order to obtain acetaminophen, a popular analgesic-antipyretic, through microbial p-hydroxylation and N-acetylation of aniline, various fungi and bacteria were secreened. Among them, Streptomyces species were chosen for strain improvement by the use of interspecific protoplast fusion technique. Two interspecific fused strains were developed between S. rimosus (N-cetylation function) and S. aureofaciens (p-hydroxylation function) and also between S. lividans and S. globisporus. For efficient protoplast fusion and cell wall regeneration, various conditions were examined. In a typical experiment of mixed S rimosus ($pro^- \;his^-$) and S. aureofaciens ($ilv^-$) protoplasts with 40% (w/v) polythylene glycol 3350 (PEG) for 3 min gave $8.3\times10^{-7}$ of fusion frequency. Treatment of mixed S. lividans (pant-) and S. globisporus (leu-) protoplasts with 50% (w/v) PEG for 3 min at $30^\circ{C}$ gave $1.2\times10^{-6}$ of frequency. Among the fused strains, up to 40-50% increase in p-hydroxylation power was observed. To investigate the possibility of plasmid involvement in p-hydroxylation power was observed. To investigate the possibility of plasmid involvement in p-hydroxylation of acetanilide, plasmid curing was attempted. We found that cells treated with acriflavine (at the frequency of 100%) and cells regenerated from protoplsts of S. auroefaciens (2% frequency) lost their p-hydroxylation function.

• Food Science and Preservation
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• v.14 no.2
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• pp.194-200
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• 2007

In order to enhance the functionality and storage period of traditional fermented foods, the strain CH-14, which To enhance the quality of traditional fermented foods, and to lengthen acceptable storage periods, a bacterial strain, CH-14, showing potent enzyme activities and antibacterial capabilities, was isolated and characterize4 The bacterium wn Gram-positive, catalase-positive, oxidase-negative, formed endospores, expressed flagella, was rod-shaped, and had dimensions of 0.5 0.7m and 3.5 4.2m. The bacterium CH-14 was identified as Bacillus subtilis using Bergey's Manual of Systematic Bacteriology, Bergey's Manual of Determinative Bacteriology, and an API 50 CHL Carbohydrate Test Kit. An optimum growth medium contained 2% (w/v) cellobiose as a carbon source, a mixture of 0.5% (w/v) yeast extract and 0.5% (w/v) peptone as nitrogen sources, and 0.05% (w/v) $MgSO_4{\cdot}7H_2O$. The optimal culture temperature and the optimal initial pH were in the ranges of 30 $45^{\circ}C$ and 4.5 10.0, respectively. Maximum production of the antibacterial substance occurred after 24h of culture. The minimum inhibitory concentrations of the antibacterial substance were 5mg bacterial dry weight/mL against E. coli and P. mirabilis, and 10 mg/mL against S. aureus, S. enteritidis and V. parahaemolyticus.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.10
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• pp.51-58
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• 1993

N-channel TFTs fabricated on the pre-amorphized (by Si ion implantation) and recrystallized Si film having 10.1V threshold voltage, 20.7cm$^{2}$/V$\cdot$s field effect mobility and ~10$^{5}$/ ON/OFF ratio, whowed improved characteristics comparing to those obtained from the as-deposited (by LPCVD) poly Si film which had 11.2V, 9cm$^{2}$/V$\cdot$s and ~10$^{4}$ respectively.

• Korean Journal of Crystallography
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• v.14 no.2
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• pp.110-114
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• 2003

LiAl/sub 0.24/Mn/sub 1.76/O/sub 4-y/S/sub y/ (y=0, 0.02) were synthesized by the sol-gel method. Both structures were refined by Rietveld method, its structure refined as a cubic spinel, space group Fd-3m, a=8.17937(30) Å and 8.18331(19) Å respectively. Though it has been made a charge/discharge experiment above 20 times, there was no change of 3 V/4 V capacity degradation. It was considered that the volume change of MnO/sub 6/ octahedron induced by sulfur substitution plays a key role in keeping the 3 V/4 V capacity. The refined composition of the compound could be confirmed with the ICP analysis.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.7
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• pp.423-426
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• 2017

The designing approaches with consideration offabrication process technologies for high-frequency, high-powered, silicon-based static induction thyristors (SITH) are presented. The effects of doping concentration and thickness on the I-V characteristics and power performance of the devices are discussed. The dependence of SITH switching performances on material, geometric structure, and technological parameters isexamined by using two-dimensional simulations. Thick-epitaxy technology is found to be one of the most critical steps in realizing the proposed structure and switching times, $t_{off}$, of SITH, which may be reduced to below ${\sim}0.26{\mu}s$ for the proposed 1,700 V SITH devicesafter optimization.