• Korean Journal of Veterinary Research
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• v.50 no.3
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• pp.221-229
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• 2010

Encephalomyocarditis virus (EMCV) belongs to the genus Cardiovirus within the family Picornaviridae. EMCV has been recognized either as a cause of mortality in young pigs, due to acute myocarditis, or of reproductive failure in sows. An EMCV K3 strain was isolated from the heart and brain in a mummified and aborted swine fetus in 1989. For the molecular characterization of the poly(C)-tract of EMCV Korean isolates, K3 strain, viral RNA was extracted and digested with RNase T1, and analyzed the length of the poly(C)-tract by polyacrylamide gel electrophoresis. The poly(C) regions also were amplified by RT-PCR and sequenced. The present study shows that K3 strain of EMCV had a short polymorphic poly(C) tracts (5 to 30 C's) with sequences consisting of $C_9$, $C_{10}$, $C_{13}$, $C_{14}$, $C_{16}$, $C_{20}$, $CUC_{11}$, $C_8UCUC_3UC_{10}$, $C_9UCUC_3UC_{10}$, $C_{10}UCUC_3UC_{10}$, etc. These polymorphism of poly(C)-tracts of EMCV K3 strain implies the historical information of in vivo and/or in vitro passage.

• Journal of Adhesion and Interface
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• v.6 no.4
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• pp.1-6
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• 2005

In this work, the effect of chemical treatments on surface properties of SiC was investigated in crack resistance properties of SiC/epoxy composites. The surface properties of SiC were determined by acid/base values and FT-IR measurements. Also the crack resistance properties of the composites were studied in critical strain energy release rate mode II ($G_{IIC}$) measurements. As a result, the acidically treated SiC had higher acid value than that of untreated SiC or basically treated SiC. The crack resistance properties of the composites had been improved in the specimens treated by acidic solution. These results were could be attributed to the acide-base intermolecular interaction between SiC and epoxy resin, resulting in increase of the degree of adhesion at interfaces.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.97-100
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• 2001

This paper presents the characteristics of Ta-N thin-film strain gauges as high-temperature strain gauges, which were deposited on Si substrate by DC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-(4~16%)$N_2$). These films were annealed for 1 hour in $2{\times}10^{-6}$ Torr vaccum furnace range $500\sim1000^{\circ}C$. The optimized conditions of Ta-N thin-film strain gauges were annealing condition($900^{\circ}C$, 1 hr.) in 8% $N_2$ gas flow ratio deposition atmosphere. Under optimum conditions, the Ta-N thin-films for strain gauges is obtained a high resistivity, $\rho=768.93$ ${\mu}{\Omega}cm$, a low temperature coefficient of resistance, TCR=-84 ppm/$^{\circ}C$ and a high temporal stability with a good longitudinal gauge factor, GF=4.12.

• Journal of Microbiology and Biotechnology
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• v.2 no.2
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• pp.78-84
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• 1992

Streptomyces sp. No.8, which produced glucose isomerase was isolated from soil samples. The isolated strain, No.8, was identified as belonging to the Genus Streptomyces. A mutant strain, SM 805, showed the greatest ability to produce glucose isomerase. It was developed from the strain, No.8, by mutagenesis induced by NTG and UV treatment. The mutant strain, SM 805, produced about 7 times more glucose isomerase than the parental strain, No.8. This enzyme catalyzed the isomerization of D-xylose, D-glucose and D-ribose. It was inactive in the absence of metal ions, but was activated by the addition of $Mg^{2+}$ or $Co^{2+}$. The optimum temperature and pH for enzyme activity were $80^\circ{C}$ and pH 8.5, respectively. The enzyme was stable in a pH range of 6.0 to 10.0, and it was highly thermostable. There was no activity loss below $80^\circ{C}$, and even above $90^\circ{C}$ about 45% of its activity was retained. The reaction equilibrium was reached when about 53% fructose was present in the reaction mixture. Whole cells containing glucose isomerase from Streptomyces sp. SM 805 were immobilized by glutaraldehyde treatment. The resultant immobilized enzyme pellets showed a relatively long stability during the isomerizing reaction. The half-life of the immobilized enzyme during the operating was 45 days in the presence of 10mM $Mg^{2+}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.376-377
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• 2006

This paper presents the characteristics of Ta-N thin film strain gauges that are suitable for harsh environemts, which were deposited on thermally oxidized Si substrates by DC reactive magnetronsputtering in an argon-nitrogen atmosphere (Ar-$N_2$ (4 ~ 16 %)). These films were annealed for 1 hr in $2{\times}10^{-6}$ Torr in a vacuum furnace with temperatures that ranged from 500 - $1000^{\circ}C$. The optimized deposition and annealing conditions of the Ta-N thin film strain gauges were determined using 8 % $N_2$ gas flow ratio and annealing at $900^{\circ}C$ for 1 hr. Under optimum formation conditions, the Ta-N thin film strain gauges obtained a high electrical resistivity, ${\rho}\;=\;768.93\;{\mu}{\Omega}{\cdot}cm$, a low temperature coefficient of resistance, $TCR\;=\;-84\;ppm/^{\circ}C$ and a high temporal stability with a good longitudinal gauge factor, GF=4.12. The fabricated Ta-N thin film strain gauges are expected to be used inmicromachined pressure sensors and load cells that are operable under harsh environments.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.8
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• pp.381-386
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• 2006

In this study, we have investigated electrical and mechanical properties of semiconducting materials for power cable caused by CNT. Specimens were made of sheet form with the four of specimens for measurement. Volume resistivity of specimens was measured by volume resistivity meter after 10 minutes in the pre-heated oven of both $23{\pm}\;1\;[^{\circ}C]\;and\;90{\pm}\;1\;[^{\circ}C]$. And stress-strain of specimens was measured by TENSOMETER 2000. A speed of measurement was 200[mm/min], ranges of stress and strain were 400[Kgf/Cm2] and 600[%]. From this experimental results, the volume resistivity had different properties because of PTC/NTC tendency at between $23[^{\circ}C]\;and\;90[^{\circ}C]$. Also volume resistivity was low by increasing the content of CNT. It means that a small amount of CNT has a excellent electrical properties. And stress was increased, while strain was decreased by increasing the content of CNT. Thus, we could know that a small amount of CNT has a excellent electrical and mechanical oroperties.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.99-105
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• 1994

Clotridium bovis sp. nov, is described on the basis of 5 strains isolated from the feces of Holstein cattle. The isolate are gram-positive, motile, strict anaerobic spore forming rods. They differ from all the validly described related species of the genus Clostridium in carbohydrate fermentation pattern, G+C mol% and DNA homologies. Acid is produced from arabinose, xylose, glucose, mannose, fructose, galactose, sucrose, maltose, cellobiose, lactose, trehalose, melibiose, raffinose, inulin and salicin. Major end products in PYFG broth are large amounts of butyric acid and lactic acid, and trace amounts of acetic and succinic acids. The G+C mol% of DNA from the type strain is 26 mol%. The type strain of Clostridium bovis is Catt $66^T$ strain.

• Journal of Microbiology and Biotechnology
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• v.33 no.11
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• pp.1448-1456
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• 2023

A Gram-positive, non-motile, and non-spore-forming lactic acid bacterium, designated as BK2^T, was isolated from kimchi, a Korean traditional fermented vegetable food, and the taxonomic characteristics of strain BK2^T, along with strain LMG 11983, were analyzed. Both strains optimally grew at 30℃, pH 7.0, and 1.0% NaCl. Cells of both strains were heterofermentative and facultatively anaerobic rods, demonstrating negative reactions for catalase and oxidase. Major fatty acids (>10%) identified in both strains were C_18:1 ω9c, C_16:0, and summed feature 7 (comprising C_19:1 ω6c and/or C_19:1 ω7c). The genomic DNA G+C contents of both strains were 44.7 mol%. The 16S rRNA gene sequence similarity (99.9%), average nucleotide identity (ANI; 99.9%), and digital DNA-DNA hybridization (dDDH; 99.7%) value between strains BK2^T and LMG 11983 indicated that they are different strains of the same species. Strain BK2^T was most closely related to Weissella confusa JCM 1093^T and Weissella cibaria LMG 17699^T, with 100% and 99.4% 16S rRNA gene sequence similarities, respectively. However, based on the ANI and dDDH values (92.3% and 48.1% with W. confusa, and 78.4% and 23.5% with W. cibaria), it was evident that strain BK2^T represents a distinct species separate from W. confusa and W. cibaria. Based on phylogenetic, phenotypic, and chemotaxonomic features, strains BK2^T and LMG 11983 represent a novel species of the genus Weissella, for which the name Weissella fermenti sp. nov. is proposed. The type of strain is BK2^T (=KACC 22833^T=JCM 35750^T).

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.556-558
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• 1995

A strain which showed cephalosporin C resistance and 7-aminocephalosporanic acid sensitivity was isolated from nature. Among the isolates, SS5 was sensitive to cephalosporin C, penicillin G, ampicillin, 7-aminocephalosporanic acid, 6-aminopenicillanic acid, and 7-aminodeacetoxy cephatosporanic acid at concentrations of 1,000 $\mu $g/ml, 2,000 $\mu $g/ml, 3,000 $\mu $g/ml, 30 $\mu $g/ml 100 $\mu $g/ml and 100 $\mu $g/ml, respectively. But SS5 was sensitive at very low concentration of chloramphenicol, kanamycin, neomycin, streptomycin and tetracycline. Since SS5 was sensitive to 7-ACA (30 $\mu $g/ml) and didn't have $\beta $-lactamase activity on the cephalosporin C, SS5 could be useful as an indicator strain for the production of 7-ACA, which is an important precursor for the synthesis of many semisynthetic cephalosporins.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05a
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• pp.771-776
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• 1995

Tensile and J-R tests were carried out to estimate the effects of dynamic strain aging(DSA) on SA106Gr.C piping steel. Tensile tests were performed under temperature range RT to $400^{\circ}C$ md strain rates from $1.39{\times}10^{-4}\;to\;6.95{\times}10^{-2}/s$. Fracture toughness was tested in the temperature range RT to $350^{\circ}C$ and load-line displacement rates 0.4 and 4mm/min. The effects of DSA on the tensile properties were clearly observed for phenomena such serrated flow, variation of ultimate and yield stress, and negative stram rate sensitivity. However, the magnitude of serration and strength increase by DSA was relatively small. this may be due to high ratio of Mn to C. In addition, crack initiation resistance, Ji and crack growth resistance, dJ/da were reduced in the range of $200-300^{\circ}C$, where DSA appeared as serrated flow and UTS hardening. The temperature corresponding to minimum fracture resistance was shifted to higher temperature with increasing loading rate.