• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.253-259
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• 1998

The stimulated secretion of golden varnish sap by the infection of microorganisms on the bark of Dendropanax morbifera Lev. was observed in the natural habitats. Four candidate strains of such microorganisms(i.e., Sb1, Sb2, Sb3 and Sb4) were isolated from the bark of D. morbifera which was infected in natural. Of them, Sb3 and Sb4 strains showed stimulated secretion of golden vernish sap with the greatest stimulation by Sb4 strains. The yield of golden varnish sap from the bark of D. morbifera was boosted about 3.4~7.7 times by the inoculation of Sb4 strain in compassion with that collected from lacquer tree(Rhus verniciflua Stokes) by the traditional method. The mycelium color of Sb4 strain was grayish white. The optimum growth temperatures and pH were ranged from 30 to $35^{\circ}C$ and from pH 6.5 to 7.0.

• KSBB Journal
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• v.30 no.3
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• pp.132-139
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• 2015

In order to use the symbiotic bacteria from ethomophatogenic nematodes as a biological control agent for agriculture, the cultural condition for maintaining phase I and antifungal activity was investigated. Symbiotic bacteria (SB) 1 stain from nematodes were selected from the three strains isolated from entomopathogenic nematodes. The growth of the SB 1 strain in NB, TSB, TY and YS medium was higher than that of the SB 2 and SB 3 strain. The packed cell volume of the SB 1 strain was reduced in NB medium which showed radical pH change. Phase I of the SB 1 strain was maintained in TSB medium after being stored for 2 weeks at $4^{\circ}C$. Culture broth with the SB 1 strain in TSB medium for 6 days and 7 days showed antifungal activities against Rhizoctonia solani KACC 40142, Botrytis cinerea Pers. KACC 40854, and Botrytis cinerea Pers. KACC 41008. Culture broth with the SB 1 strain in TSB medium containing 100 mM L-proline for 5 days showed antifungal activities against Rhizoctonia solani KACC 40142, and Botrytis cinerea Pers. KACC 40854.

• Plant Resources
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• v.4 no.1
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• pp.41-47
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• 2001

This study was conducted to investigate the occurrence of Soil borne wheat mosaic virus(SbWMV) in barley fields in Korea and to examine the host pathogenicity of SbWMV. By using the ELISA test, SbWMV was detected in the six regions : Suwon, Milyang, Jinju, Youngkwang, Iksan, and Chonju. SbWMV was isolated from the two strains, Albori strain from Jinju and Eunpamil strain from Milyang. SbWMV was collected from leaves showing mosaic, yellowing and necrosis stripes. SbWMV was inoculated mechanically on 1∼1.5 leaf stages with leaf-rubbing to identify the host pathogenicity of 36 Korean barley cultivars, a wheat cultivar, two rye cultivars, three Japanese barley cultivars and Chenopodium amaranticola. Viral sympoms of inoculated leaves appeared on moulted loaves about 4 to 6 weeks of inoculation. Baegdong and Tapgolbori, infected from Albori strain and Eunpamil strain infected from Samdobori showed much higher susceptibility than C. amaranticola and C. quinoa which showed ring spots and chlorotic spots respectively. Virus particles were observed by the electron microscope. They were rod-shapes, which are bipartite, of 142 nm or 281 nm in length with 20 nm diameter on infected leaves. Specific detection and identification of SbWMV was set up using the RT-PCR. PCR fragments of SbWMV(0.5kb) were obtained by using the designed primers for SbWMV RNA 2.

• Journal of the Korean Vacuum Society
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• v.18 no.4
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• pp.245-253
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• 2009

For the growth optimization of InAs/GaSb (8/8-ML) strained-layer superlattice (SLS), the structure has been grown under various conditions and modes and characterized by the high-resolution x-ray diffraction (XRD) analysis. In this study, the strain modulation is induced by changing parameters and modes, such as the growth temperature, the ratio of V/III beam-equivalent-pressure (BEP), and the growth interruption (GI), and the strain variation is analyzed by measuring the angle separation of 0th-order satellite peak in XRD patterns. The XRD results reveal that the growth temperature and the V/III(Sb/Ga) ratio are major parameters to change the crystallineity and the strain modulation in SLS structures, respectively. We have observed that the SLS samples with compressive strain prepared in this study are show a transition to tensile strain with decreasing V/III(Sb/Ga) ratio, and the GI process is a sensitive factor giving rise to strain modulation. These results obtained in this study suggest that optimized growth temperature and V/III(Sb/Ga) ratio are $350^{\circ}C$ and 20, respectively, and the appropriate GI time is approximately 3 seconds just before InAs growth that the crystallineity is maximized and the strain relaxation is minimized.

• Parasites, Hosts and Diseases
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• v.33 no.4
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• pp.387-390
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• 1995

In the present communication, YS-27, a Korean strain of Entnnloeba histoIWtica is described for the isolation and establishment of axonic cultivation. 5. histoLvticc, designated as strain "YS-27" was isolated from the pus of a hepatic abscess obtained from a 72 you old inpatient of August 10, 1969. Specimens, were obtained by needle aspiration, inoculated immediately and weekly cultured in a modified diphasic medium at 37℃. Strain YS-27 had been maintained for more than 15 years by weekly subculture until February, 1985. These cultures were transferred to a monoxenic TTY-SB medium seeded with a trypanosomatid of the genus CyithidiG. Penicillin G, 2 to 10 H 103 International units and Streptomycin, 2 to 10 mg per 100 ml, were added to the cultures to eliminate the bacteria. After more than one year later, these two organisms were well maintained by transfer every 3 or 4 days until .January. 1986 at 37℃ in TTY-SB medium in the absence of other microorganisms. These monoxenic cultures were then transferred to TYI-S-33 medium. Strain YS-27 alone had not been growing at the time of transfer, but when overlaid with Crithinia at intervals of 3 to 4 days, strain YS-27 propagated well. The Clthidio died out several weeks later after several passages. Beginning in April, 1986, strain YS-27. was successfully established in axonic culture in TYI-S-33 medium and has been maintained in continuous culture and multiplied well to present.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.407-412
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• 1988

In order to increase the tryptophan productivity of E. coli SB1007, a mutant resistant to sulfanilamide was isolated and then a tyrosine auxotroph TY-90 was derived from the sulfanilamide-resistant mutant SA3-39-16. In the test-tube culture a quantitative amount of tryptophan was accumulated in strain TY-90 but in a jar fermentor culture the productivity was lower as compared to the level obtained by the parent strain. From the double auxotrophic mutant SB2756, a revertant resistant to 2, 000$\mu\textrm{g}$/$m\ell$ of $\beta$-thienylalanine, TA 40-10, was selected and then phenylalanine auxotrophs were derived from the revertant strain TA-40-10. One of the phenylalanine auxotrophs, TP-4, accumulated 3.7g/$\ell$ of L-tryptophan after 71-hr cultivation in a jar fermentor experiment.

• Advances in nano research
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• v.2 no.4
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• pp.211-217
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• 2014

The self-assembled strain-induced sub-micrometric islands and nanostructures are grown from In-As-Sb-P quaternary liquid phase on InAs (100) substrates in Stranski-Krastanow growth mode. Two samples are under consideration. The first sample consists of unencapsulated islands and lens-shape quantum dots (QDs) grown from expressly inhomogeneous liquid phase. The second sample is an n-InAs/p-InAsSbP heterostructure with QDs embedded in the p-n junction interface. The morphology, size and shape of the structures are investigated by high-resolution scanning electron (SEM) and transmission electron (TEM) microscopy. It is shown that islands, as they decrease in size, undergo shape transitions. Particularly, as the volume decreases, the following succession of shape transitions are detected: sub-micrometric truncated pyramid, {111} facetted pyramid, {111} and partially {105} facetted pyramid, completely unfacetted "pre-pyramid", hemisphere, lens-shaped QD, which then evolves again to nano-pyramid. A critical size of $5{\pm}2nm$ for the shape transformation of InAsSbP-based lens-shaped QD to nano-pyramid is experimentally measured and theoretically evaluated.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.5
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• pp.151-156
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• 2007

In this paper, the creep characteristics of lead and lead-free solder joint were investigated using the QFP(Quad Flat Package) creep test. Two kind of solder pastes(Sn-3Ag-0.5Cu, Sn-0.2Sb-0.4Ag-37.4Pb) were applied to the QFP solder joints and each specimen was checked the external and internal failures(i.e., wetting failure, void, pin hole, poor-heel fillet) by digital microscope and X-ray inspection. The creep test was conducted at the temperatures of $100^{\circ}C$ and $130^{\circ}C$ under the load of 15$\sim$20% of average pull strength in solder joints. The creep characteristics of each solder joints were compared using the creep strain-time curve and creep strain rate-stress curves. Through the comparison, the Sn-3Ag-0.5Cu solder joints have higher creep resistance than that of Sn-0.3Sb-0.4Ag-37.4Pb. Also, the grain boundary sliding in the fracture surface and the necking of solder joint were observed by FE-SEM.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.82-87
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• 2006

Twenty one strains strongly producing protease were isolated from Korean traditional Cheonggukjang. Eight strains selected by sensory evaluation on Cheonggukjang prepared with isolated strains were identified with based on biochemical properties a and 16S rDNA sequencing. Identified strains were Bacillus subtilis MB4, and Bacillus amyloliquefaciens A1, A2, B1, MC1, SB2, SC1, and SD1. Protease activities, important strain selection factor, were higher in Cheongjukjang prepared with B. subtilis MB4 (179.6 Unit) and B. amyloliquefaciens SB2 (201.9 Unit) than commercial traditional Cheonggukjang (97.9 Unit). Sensory evaluation revealed Cheonggukjang prepared with B. subtilis MB4 had flavor very similar to commercial traditional Cheonggukjang. Cheonggukjang prepared with B. suhtilis MB4 (0.0006 Pa s) and commercial traditional Cheonggukjang (0.0002 Pa s) revealed lower viscosities than those of Cheonggukjang prepared with B. amyloliquefaciens SB2, MC1, B1, A1, SD1, A2, and SC1 (0.006 to 0.008 Pa s at 1001/s. Results show Cheonggukjang could be prepared using single strain of B. subtilis MB4, maintaining high protease activity and very similar sensory and viscosity qualities with those of commercial traditional Cheonggukjang.

• Microbiology and Biotechnology Letters
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• v.1 no.1
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• pp.37-42
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• 1973

C-74 belonging to the genus of Aspergillus species was selected from two hundred and seventy microorganisms stored at the lab, of microbiology. 1. Sample Inulase was precipitated mainly at pH 8 to 5 by isoelectric point fraction method. 2. The optimum pH of Inulase activity of the enzyme from C-74 strain was about 3.0 3. The optimum temperature of Inulase activity of the enzyme from C-74 strain was about $55^{\circ}C$ 4. The Inulase from C-74 strain was stable at $50^{\circ}C$ for 10mins. 5. The range of the pH stability of the Inulase from C-74 strain was about 2.5-4.5 6. Effect of metal ions on the Inulase activity of the enzyme from C-74 strain was activated by Mg$\^$++/, Sb$\^$+++/ and inhibited by Ag$\^$++/, Hg$\^$++/.