• Journal of Information Display
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• 제7권4호
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• pp.13-16
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• 2006

II-$III_{2}-(S,Se)_{4}$ structured of phosphor have been used at various fields because they have high luminescent efficiency and broad emission band. Among these phosphors, europium doped $BaGa_{2}S_{4}$ was prepared by solid-state method. We investigated the possibility of applying [ ] due to emissive property of UV region. Also, general sulfide phosphors were synthesized by using injurious $H_{2}S$ $CS_{2}$ gas. However, this study prepared $BaGa_{2}S_{4}:Eu^{2+}$ phosphor is addition to excess sulfur under 5% $H_{2}$/95% $N_{2}$ reduction atmosphere. So, this process could involved large scale synthesis because of non-harmfulness and simple process. The photo-luminescence efficiency of the prepared $BaGa_{2}S_{4}:Eu^{2+}$ phosphor increased by 20% compared with commercial $BaGa_{2}S_{4}:Eu^{2+}$ phosphor. From this, we could conclude that the prepared $BaGa_{2}S_{4}:Eu^{2+}$ could be applied to green phosphor for white LED of three wavelengths.

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.822-826
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• 2008

We report the cathodoluminescence and aging properties of a series of green phosphors of formula $Sr_{1-x}M_xGa_2S_4$:Eu (x = 0.0-1.0, M = Ba or Ca) that have potential applications in field emission displays (FEDs). The series of phosphors was synthesized via NaBr-aided solid-state reactions in a flowing $H_2S$ stream. A low level ($\sim$20%) of Ba or Ca substitution for Sr in $SrGa_2S_4$:Eu maintains the orthorhombic phase of pure $SrGa_2S_4$:Eu phosphors. Further, a low level ($\sim$20%) of Ba or Ca substitution for Sr in $SrGa_2S_4$:Eu provides various green colors and sufficient brightness for FED applications. Substitution of Ba or Ca for Sr in $SrGa_2S_4$:Eu also improved the stability of the phosphor when it was operated under electron-beam irradiation of 5 kV.

• 한국재료학회지
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• 제16권12호
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• pp.761-765
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• 2006

[ $II-III_2-(S,Se)_4$ ] structured of phosphor has been used at various field because those have high luminescent efficiency and broad emission band. Among these phosphors, the europium doped $BaGa_2S_4$ was prepared by solid-state method and had high potential application due to an emissive property of UV region. Also, the common sulfide phosphors were synthesized by using injurious $H_2S\;or\;CS_2$ gas. However, in this study $BaGa_2S_4:Eu^{2+}$ phosphor in addition to excess sulfur was prepared under at 5% $H_2/95%\;N_2$ reduction atmosphere. Thus, this process could be considered as large scale synthesis because of non-harmfulness and simplification. The photoluminescence efficiency of the prepared $BaGa_2S_4:Eu^{2+}$ phosphor increased 20% than that of commercial $SrGa_2S_4:Eu^{2+}$ phosphor. The prepared $BaGa_2S_4:Eu^{2+}$ could be applied to green phosphor for white LED of three wavelengths.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1096-1099
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• 2006

$II-III_2-(S,Se)_4$ structured of phosphor have been used at various field because those have high luminescent efficiency and broad emission band. Among these phosphors, europium doped $BaGa_2S_4$ was prepared by solid-state method and we try to look into an application possibility due to an emissive property of UV region. Also, general sulfide phosphors were synthesized by using injurious $H_2S\;CS_2$ gas. However, this study prepared $BaGa_2S_4:Eu^{2+}$ phosphor is addition to excess sulfur under 5% $H_2/95%\;N_2$ reduction atmosphere. So, this process could large scale synthesis because of non-harmfulness and simple process. The photo-luminescence efficiency of the prepared $BaGa_2S_4:Eu^{2+}$ phosphor increased 20% than commercial $SrGa_2S_4:Eu^{2+}$ phosphor. The prepared $BaGa_2S_4:Eu^{2+}$ could apply to green phosphor for white LED of three wavelengths.

• Applied Biological Chemistry
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• 제29권1호
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• pp.73-77
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• 1986

Auxin과 cytokinin 그리고 $GA_3$가 대두(Glycine max) 종자의 단백질 합성과 축적에 미치는 영향을 보기 위하여, 2,4-D와 BA 그리고 $GA_3$을 각각 $10^{-6},\;10^{-5},\;10^{-4}M$의 수용액으로 만들어 개화기에 식물체 전체에 살포 처리하고 개화 후 33일의 미숙종자와 77일의 완숙종자에 대한 단백질 전기영동 양상을 조사하였다. $GA_3$는 단백질 합성과 축적에 영향을 주지 않았으나 2,4-D와 BA는 일정농도에서 특정 단백질들의 축적에 영향을 주었다. 7S의 ${\alpha}$와 ${\alpha}'$ subunit, 11S의 acidic subunit 들이 2,4-D 혹은 BA처리에 의하여 나타나지 않았으며, 이 subunit들이 성숙종자에 없으나 미숙종자에는 있는 점으로 보아, 2,4-D나 BA는 이들의 함성을 저해하는 것이 아니고 축적과정의 어느 단계에서 이 subunit들의 분해 혹은 전환을 촉진하는 것으로 생각되었다. 2,4-D와 BA에 의해 위의 단백질이 성숙종자에 축적되지 않는 것은 어떤 단백질분해효소(metalloendopeptidase?)의 작용과 관련이 있는 것으로 보이며, 2,4-D나 BA는 성숙후기에 이 효소의 gene expression을 촉진하거나 활성을 증진시키는 것으로 생각되었다.

• 대한화학회지
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• 제47권4호
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• pp.370-375
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• 2003

보라색 발광 다이오드에 의해 여기되어 청색, 녹색, 적색을 발광하는 형광체로 각각 $BaMg_2Al_16O_27:Eu,\SrGa_2S_4:Eu$, ZnCdS:Ag,Cl 형광체를 선택하였다. 보라색 발광 다이오드의 발광에서 형광체에 의해서 완전히 흡수되지 않고 나오는 보라색 발광과 $BaMg_2Al_16O_27:Eu,\SrGa_2S_4:Eu$, ZnCdS:Ag,Cl 형광체에서 나오는 청색, 녹색, 적색 발광을 조합하여 사파장 백색 발광 다이오드를 만들었다. 사파장 백색 발광 다이오드의 발광 특성을 확인하였다.

• 한국세라믹학회지
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• 제36권10호
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• pp.1056-1061
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• 1999

Phase formation and oxygen ion conduction of La(Ba)Ga(Mg)O3-$\delta$ system was studied, BaLaGa3O7 and BaLaGaO4 formed as a secondary phase above the solubility limit of Ba2+ in La3+ sites. The oxygen ionic conductivity of La(Ba)Ga(Mg)O3-$\delta$ was 0.1 S/cm 80$0^{\circ}C$ The activation energy of the oxygen ion conduction was dependent on temperature. This value was higher at low temperature than at high temperature.

• Applied Biological Chemistry
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• 제28권3호
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• pp.187-195
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• 1985

당근에서 cytokinin, auxin 또는 GA에 의해 조절되는 polypeptide 및 단백질들을 동정하기 위하여, kinetin, BA, IAA, NAA 혹은 $GA_3$가 각각 $10^{-4},\;10^{-5},\;10^{-6}M$인 배지에서 suspension culture 한 당근 callus들의 추출물의 전기영동양상을 조사하였다. 생장조절제를 처리하지 않은 callus에서 15개 polypeptide band가 관찰되었는데, 이들의 분자량은 각각 $18._4,\;20._2,\;24._0,\;34._9,\;35._7,\;37._4,\;40._3,\;42._2,\;44._1,\;44._4,\;49._3,\;55._0,\;56._6,\;58._1$ 그리고 $59._9KD$였다. Kinetin, BA, IAA, NAA 그리고 $GA_3$에 의하여 합성이 촉진되는 것으로 보이는 polypeptide band는 각각 2개, 6개, 1개, 2개 그리고 4개였고, 합성이 억제되는 것으로 보이는 것은 각각 5개, 3개, 4개, 3개, 그리고 2개였다. 분자량 $40._3KD$ 및 $42._2KD$의 polypeptide들은 cytokinin류 생장조절제에 의하여 합성이 촉진되는 것으로 나타났고, $44._1KD$의 것은 auxin류에 의하여 합성이 촉진되며 $37._4,\;44._4,\;56._6KD$의 것은 auxin류에 의하여 합성이 억제되는 것으로 나다났다. Kinetin, BA, IAA, NAA 및 $GA_3$처리에서 상대 이동도가 0.56, 0.84, 0.92인 단백질 band들이 증가된 것이 관찰되었으나, 각 생장조절제들에 특유한 단백질은 동정할 수 없었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.561-564
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• 2008

$Ba_{1-x}M_xGa_2S_4:Eu^{2+}$ (M = Ca, Sr) phosphor was prepared for white light emitting diodes application. Photoluminescence (PL) emission and excitation bands were red-shifted with increase of Ca and Sr content due to the crystal field effect. Moreover, the PL intensity under 450 nm was increased by substitution of Ca and Sr.

• 한국결정성장학회지
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• 제25권5호
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• pp.173-181
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• 2015

A stoichiometric mixture of evaporating materials for $BaIn_2S_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $BaIn_2S_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $620^{\circ}C$ and $420^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by double crystal X-ray diffraction (DCXD). The carrier density and mobility of $BaIn_2S_4$ single crystal thin films measured from Hall effect by van der Pauw method are $6.13{\times}10^{17}cm^{-3}$ and $222cm^2/v{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $BaIn_2S_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=3.0581eV-(3.9511{\times}10^{-3}eV/K)T^2/(T+536K)$. The crystal field and the spin-orbit splitting energies for the valence band of the $BaIn_2S_4$ have been estimated to be 182.7 meV and 42.6 meV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $BaIn_2S_4/GaAs$ epilayer. The three photocurrent peaks observed at 10 K are ascribed to the $A_1$-, $B_1$-exciton for n = 1 and $C_{24}$-exciton peaks for n = 24.