• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.1
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• pp.176-181
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• 2009

In this work, a new type of DSCs based on nanoporous FTO structure is being developed for research aimed at low-cost high-efficiency solar cell application. The nanoporous FTO materials have been prepared through the sol-gel combustion method followed by thermal treatment at $450{\sim}850[^{\circ}C]$. The properties of the nanoporous FTO materials were investigated by IR spectra, BET and TEM analyses, and the photovoltaic performance of the prepared DSCs were examined. It can be seen from the result that the nanoporous FTO exhibited good transparent conductive properties, well suited for DSCs application.

• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1774-1780
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• 2016

Vegetative insecticidal proteins (Vips) are insecticidal proteins synthesized by Bacillus thuringiensis during the vegetative stage of growth. In this study, Vip3Aa protein, obtained by in vitro expression of the vip3Aa gene from B. thuringiensis WB5, displayed high insecticidal activity against Spodoptera litura aside from Spodoptera exigua and Helicoverpa armigera. Bioassay results showed that the toxicity of Vip3Aa protein against S. litura larvae statistically decreased along with the increase of the age of the larvae, with LC₅₀ = 2.609 ng/cm² for neonatal larvae, LC₅₀ = 28.778 ng/cm² for first instar larvae, LC₅₀ = 70.460 ng/cm² for second instar larvae, and LC₅₀ = 200.627 ng/cm² for third instar larvae. The accumulative mortality of 100% larvae appeared at 72 h for all instars of S. litura larvae, when feeding respectively with 83.22, 213.04, 341.40, and 613.20 ng/cm² of Vip3Aa toxin to the neonatal and first to third instar larvae. The histopathological effects of Vip3Aa toxin on the midgut epithelial cells of S. litura larvae was also investigated. The TEM observations showed wide damage of the epithelial cell in the midgut of S. litura larvae fed with Vip3Aa toxin.

• Journal of Powder Materials
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• v.23 no.1
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• pp.21-25
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• 2016

The microstructural properties and electrical characteristics of sputtering films deposited with a Cu-Ga target are analyzed. The Cu-Ga target is prepared using the cold spray process and shows generally uniform composition distributions, as suggested by secondary ion mass spectrometer (SIMS) data. Characteristics of the sputtered Cu-Ga films are investigated at three positions (top, center and bottom) of the Cu-Ga target by X-ray diffraction (XRD), SIMS, 4-point probe and transmission electron microscopy (TEM) analysis methods. The results show that the Cu-Ga films are composed of hexagonal and unknown phases, and they have similar distributions of composition and resistivity at the top, center, and bottom regions of the Cu-Ga target. It demonstrates that these films have uniform properties regardless of the position on the Cu-Ga target. In conclusion, the cold spray process is expected to be a useful method for preparing sputter targets.

• Journal of fish pathology
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• v.16 no.3
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• pp.153-159
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• 2003

The high mortality of cultured juvenile turbot, Scophthalmus maximus occurred in Gochang on June, 2003. The diseased fish was lethargic with reduced feed intake. Grossly, these fish showed pale body, abdominal extension and exophthalmia. The dominant internal gross features of diseased fish were severely enlarged spleen, pale gills and/ or liver. Diseased fish histologically showed basophilic enlarged cells in the kidney, spleen, gill, heart, stomach, intestine, liver, pancreas and adipose tissue. Transmission electron microscopy (TEM) reveled hexagonal virions in the cytoplasm of necrotic cells. The viral particles lead a central electron-dense core and an electron translucent zone, and were 136-159 nm in diameter. These results suggest that the virus belonging to the iridoviridae was responsible for the mortality of cultured juvenile turbot.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.650-658
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• 1988

The mobilization of proteins in the cotyledons of germinating soybean seeds (Glycine mar [L.] Merr.) and seedlings was studied by using light microscopy and transmission electron microscopy. The cotyledon tissues of soybean. were packed with protein bodies(diameter $0.1-15{\mu}m$) where storage protein of soybean is deposited. Degradation of protein bodies started in the epidermis and vascular tissues. After swelling of the protein bodies, autolysis of storage proteins began while the external membrane remained unbroken. Hydrolysis of proteins could be internal or peripheral and fusion might begin before complete protein degradation. Possible instances of vacuolar fusion were encountered in some cells. In all cases, the result of degradation was the same; the central vacuole of the cell. At the late stages of seedling growth, breakdown of tonoplast was observed in some cells.

• Journal of Powder Materials
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• v.21 no.2
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• pp.119-123
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• 2014

Pt has been widely used as catalyst for fuel cell and exhausted gas clean systems due to its high catalytic activity. Recently, there have been researches on fabricating composite materials of Pt as a method of reducing the amount of Pt due to its high price. One of the approaches for saving Pt used as catalyst is a core shell structure consisting of Pt layer on the core of the non-noble metal. In this study, the synthesis of Pt shell was conducted on the surface of $TiO_2$ particle, a non-noble material, by applying ultraviolet (UV) irradiation. Anatase $TiO_2$ particles with the average size of 20~30 nm were immersed in the ethanol dissolved with Pt precursor of $H_2PtCl_6{\cdot}6H_2O$ and exposed to UV irradiation with the wavelength of 365 nm. It was confirmed that Pt nano-particles were formed on the surface of $TiO_2$ particles by photochemical reduction of Pt ion from the solution. The morphology of the synthesized Pt@$TiO_2$ nano-composite was examined by TEM (Transmission Electron Microscopy).

• Journal of Conservation Science
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• v.23
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• pp.67-72
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• 2008

This study was conducted to examineboth the type of wood decay and the degree of degradation for the waterlogged woods (Alnus spp. and Fraxinus spp., about 5,700~5,900 year old), which were excavated at Higokri, Pyungteak in the west-coastal region of Korea. The transmission electron microscope (TEM) observation indicated the degradations by soft rot and bacteria were common in both woods. Erosion bacteria attacked gradually and irregularly from the secondary layer to compound middle lamella and often produced the cavity which was similar to soft-rot cavity but much smaller ones. Tunneling bacteria decomposed mainly $S_2$ layer. Though of highly degraded walls, the cells almost kept the original form with intact lignin-rich middle lamella, which were saturated by water. No marine borer's trace indicated that the sealine rise in the western coast of Korean peninsula during the climate optimum period in the holocene might not be high enough to submerge the Higokri area which locates about 2 km from the present sealine.

• Resources Recycling
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• v.18 no.5
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• pp.12-18
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• 2009

The 20% Pt/C catalysts were synthesized using the chemical reduction method for polymer electrolyte fuel cell cathode and were heat-treated in the temperature range from 300 to $600^{\circ}C$. The oxygen reduction reaction of the catalysts was evaluated using the electrochemical measurement. The oxygen reduction reaction of the heat-treated Pt/C at $300^{\circ}C$ had high catalytic activity and the oxygen reduction reaction current of that was 2 times than that of non-heat treatment catalyst. It is considered that the change of the crystallinity and particle size by heat treatment could increase the catalytic activity.

• KSBB Journal
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• v.9 no.1
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• pp.16-25
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• 1994

Sporulation mutants of Bacillus subtilis were developed for overproduction of heterologous proteins. The strains spoOJ spoIIG, and spoOJ spoIIG double mutant were constructed from two pretense-delfted mutant (DB104). The vector containing aprE gene was integrated in the chromosome of each strain, then the morphology of each strain was observed by TEM (trasmission electron microscopy). The morphology of spoOJ mutant and spoIIG mutant coincides with the description of the previous reports, respectively. The sporulating cells of spoOJ SpoIIG double mutation resemble spoIIG mutant more similarly, but with a little rougher cell wall membrane. The spoOJ mutation in B. subtilis gives negative effect on aprE activity with only a decreased sporulation frequency. On the contrary spoIIG mutation increases the aprE activity twice with an undetectable sporulation frequency. In the case of spoOJ and spolIG, i. e. double mutation, the effect of spoOJ on aprE activity seems to be relieved and the double mutant shows more or less the same aprE activity compared to spoIIG mutant.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6363-6368
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• 2012

Objective: The study aim was to prepare poly-DL-lactide-poly (PELA) microspheres encapsulating recombinant tissue inhibitors of metalloproteinase-1 (TIMP-1) in an adenovirus to investigate its inhibition on the proliferation of hepatocellular carcinoma cells HepG2. Methods: Microspheres were prepared by encapsulating the recombinant TIMP-1 adenovirus into biodegradable PELA. The particle size, viral load, encapsulation efficiency and in-vitro release were measured. Microspheres were used to infect HepG2 cells, then infection efficiency was examined under a fluorescent microscope and ultrastructural changes assessed by TEM. Expression of TIMP-1 mRNA in HepG2 cells was examined by semi-quantitative RT-PCR and proliferation by MTT and cell growth curve assays. Results: We successfully prepared microspheres encapsulating recombinant TIMP-1 adenovirus with a diameter of $1.965{\mu}m$, an encapsulation efficiency of 60.0%, a viral load of $10.5{\times}10^8/mg$ and approximate 60% of virus release within 120 h, the total releasing time of which was longer than 240 h. The microspheres were confirmed to be non-toxic with blank microspheres. Infected HepG2 cells could stably maintain in-vitro expression of TIMP-1, with significantly effects on biological behaviour Conclusion: PELA microspheres encapsulating a recombinant TIMP-1 adenovirus can markedly inhibit the proliferation of HepG2 cells, which provides an experimental basis for polymer/chemistry-based gene therapy of hepatocellular carcinomas.