• 한국연소학회:학술대회논문집
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• 2000.05a
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• pp.16-25
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• 2000

The differential diffusion of two species in jet is considered. The direct photo images of $H_{2}/SF_{6}$ flame are taken and the non-react jets of $H_{2}/SF_{6}$ mixture are visualized with Rayleigh scattering method. The structures of Dual flame are found in the photography. As the volume fraction of $H_2$ in mixture is increased, the flame at side is long and as the volume fraction of $SF_{6}$ in mixture is increased, the flame at center is long. This phenomena are deduced from the non-react mixture using Rayleigh scattering method. Result show that the volume fraction in the mixture is important in differential diffusion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.947-950
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• 2001

We report the characteristics of organic light emitting diodes (OLEDS) by controlling the carrier mobility according to the crystalline of Iron(II) Phthalocyanine(Fe-Pc) and metal-free Phthalocyanine (H$_2$-Pc). In order to change the recombination zone, we controlled the hole mobility by changing the crystal structures of Fe-Pc and H$_2$-Pc. OLEDs were constructed with ITO/Fe-Pc/triphenyl-diamine (TPD)/tris-(8-hydroxyquinoline)aluminum (Alq$_3$)/Al and ITO/H$_2$-Pc/triphenyl-diamine (TPD)/tris-(8-hydroxyquinoline)aluminum (Alq$_3$)/Al. The electroluminescent properties were changed according to the heat-treatments of Fe-Pc and H$_2$-Pc. We observed that the recombination zone and the carrier mobility were changed as the higher occupied molecular orbital levels of Fe-Pc and H$_2$-Pc decreased.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.97-100
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• 1998

We studied on the ultra thin L-${\alpha}$-DLPC by LB method. The $\pi$-A isotherm of the L-${\alpha}$-DLPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. The molecular arrangement of deposited films were evaluated by measuring the absorption with the UVspectrometer. And we made structures of metal(Au)/L-${\alpha}$-DLPC/Metal(Au) and examined electron through L-${\alpha}$-DLPC LB films by means of current-voltage(I-V) measurement.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.810-812
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• 1998

We studied on the $\pi$-A isotherm of the L-$\alpha$-DLPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. The molecular arrangement of deposited films were evaluated by measuring the absorption with the UVspectrometer. We made structures of metal(Au)/organic thin films (L-$\alpha$-DLPC)/Metal(Au), the number of accumulated layers are 3. And I-V characteristic of the device examined.

• YAKHAK HOEJI
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• v.41 no.3
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• pp.298-304
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• 1997

Molecular mechanics and conformation search methods were carried oyt to investigate the relationship between conformations and thromboxane synthetase ingibitory activities of om ega-pyridylalkenoic acids. The initial geometries of ${\omega}$-pyridylalkenoic acids and heme part of cytochrome P-450 were obtained from MM+ geometry optimization. The bond lenths and angles were not varied by step during the conformation searching. Stable conformers of some ${\omega}$-pyridylalkenoic acids were obtained by comformational search method. The distances were 8.5~10.8 ${\AA}$- between N atom at 3-position of pyridine ring and C atom at carboxylic group of stable ${\omega}$-pyridylalkenoic acids. The conformations of ${\omega}$-pyridylalkenoic acids and heme part complex were determined by same method. In theses structures, benzene ring and ethylene group in ${\omega}$-pyridylalkenoic acids are making the structure more rigid and increase inhbitory activity. The electron donating groups in C atom shich is connected to pyridine ring also increase activity.

• Mycobiology
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• v.42 no.2
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• pp.147-151
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• 2014

We investigated the diversity of the foliar endophytes of Korean ginseng. Endophytic fungi were isolated from healthy leaves of mountain-cultivated ginseng (MCG) and field-cultivated ginseng (FCG) at 4 sites in Chungbuk Province. A total of 24 species of fungal endophytes were identified using molecular approaches. Additionally, the diversity of these endophytic fungi was compared between MCG and FCG. The major isolated endophytes were Edenia gomezpompae and Gibberella moniliformis in the MCG and FCG samples, respectively. The results suggest that ginseng endophytes have different community structures in different environments, and this understanding may prove useful in ginseng cultivation.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.89-89
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• 2006

Polyalkylene phosphates - polymers that are built on the repeating unit of the diester of phosphoric acid: -[OP(O)(OH)Oalkylene]-, are known to form backbones of nucleic and teichoic acids. Various synthetic ways will be reported for the synthesis of the bare chains, where "alkylene" in the formula above means mostly two or three methylene groups. Some other structures have also been prepared. Several applications of these polymers are to be discussed, namely as liquid membranes, as components of two-block copolymers (ionic-nonionic diblock dihydrophilic) used as modifiers of CaCO3 crystallization, and as components of the inorganic-polymer hybrid materials. Some other applications in the biomedical field will also be discussed.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.317-317
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• 2006

Dendronized linear polymers have recently come forward as new materials for nanoscale applications. These "molecular cylinders" may be modified with specific chemical makeup, rigidity, surface decoration, and backbone properties much like their spherical analogs, dendrimers. There exist three main synthetic pathways to yield dendronized polymers: (i) graft-to; (ii) graft-from; and (iii) macromonomer. We present an efficient "graft-to" approach towards dendronized microstructures utilizing click chemistry. With the capacity to manipulate their chemical composition, these dendronized structures have already found broad use in site-isolation for catalysis, nanolithography and organic light emitting diodes. These and other potential applications of these materials will be also presented.

• Fisheries and Aquatic Sciences
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• v.8 no.1
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• pp.6-9
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• 2005

Two new cyclic peroxides were isolated from an undescribed sponge of the genus Plakortis sp. collected at Discovery Bay, Jamaica. The molecular structures were elucidated by interpreting ID and 2D NMR and HRMS data. The cyclic peroxides, Compound 1 and 2, exhibited significant antimicrobial activity against pathogenic bacteria and fungi with IC$_${50} values of 0.9-5.0$\mug/mL and 0.7-8.0$\mug/mL, respectively.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.453-456
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• 1998

The electrical properties of $Si_{1-x}Ge_{x}$ samples have been investigated. The sample structures were grown by MBE (molecular geam epitaxy) with Ge mole-fraction of x=0.0, x=0.05, x=0.1, and x=0.2. To examine the influence of the thermal processing, the $O_{2}$ and N$_{2}$ process were performed at 800[.deg. C] and 900[.deg. C], respectively. After this thermal process, hall measurements have been done over a wide range of the ambient temperature between 320[.deg. K] and 10[.deg. K] to find the temperature dependence using the comparessed-He gas system. The Ge-rich layer has been formed at the $SiO_{2}$/SiGe interface and it has an effect on the hall mobility. And it has been found that hall mobility was increased by the $N_{2}$ annealing process comparing with dry oxidation process at both 800[.deg.C] and900[.deg. C].