• Journal of the Korean Ceramic Society
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• v.35 no.4
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• pp.364-370
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• 1998

Boron-phoshor-silicate glass was fabricated on Si substrates by FHD(Flame Hydrolysis Deposition) The microstructrue of silica soot deposited at various conditon such as composition and substrate temperature was analysed by SEM. After consolidation the refractive index and composition of the silica layer were in-vestigated. For refractive index control B, P and Ge were used as additive elements while B and Ge oxides are easily mixed into $SiO_2$, P oxide($B_2O_3$) doping is difficult because of the volatile property due to low melt-ing point. Boron-phosphorous-silicate glass (BPSG) layer were fabricated using bertical torch and optimized flame temperature substrate temperature and distance of torch and substrate. P concentration of BPSG lay-er measured 3.3 Wt% and the consolidation temperature was lower than $1180^{\circ}C$. The measured refractive index of BPSG silica layer in $1.55\;\mu\textrm{m}$ wavelength was $1.4480{\pm}1{\times}10^{-1}$ and the thickness was $22{\pm}1\;\mu\textrm{m}$.

• Journal of the Korean Chemical Society
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• v.61 no.4
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• pp.163-167
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• 2017

Along with the progress of white LED technology, red phosphors have become increasingly important in industry and academia, and a more specific demand has steadily increased in the market. Red phosphors are used in high efficiency and high rendering LED lightings. However, using red phosphors with $Eu^{2+}$ activators caused color rewarming and reduced emission intensity in white LED chips due to strong reabsorption in the green or yellow wavelength range caused by the 4f-5d transition. $Mn^{4+}$ doped phosphors which have no such drawbacks and which can further improve the color rendering index (CRI) are now of great interest. However, $Mn^{4+}$-doped phosphors have a disadvantage in that the emission wavelength is determined depending on the host due to the $^2E_g{\rightarrow}^4A_2$ transition. In this study, the $SrO-BaO-GeO_2$ solid-solution was selected, and $Sr_{1-x}B_axGe_4O_9:Mn^{4+}{_{0.005}}$ ($0{\leq}x{\leq}1$) phosphors were synthesized and characterized. This led to a versatile color tuning in LED technology.

• Korean Journal of Crystallography
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• v.2 no.2
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• pp.32-40
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• 1991

The effects of compositional variation, rotation speel and pulling rate on the growth of optical quality Bi120e02(1 crystals were examined. It was found to flatten the shape of crystal-melt interface for yowing a single crystals less than about 30mm in diameter at the rotation speed of 50rpm. Diameter of crystals with flat interface was increased as the pulling rate. The precipitation of Bi40e3012 phase set limits to pulling rate of BGO crystals. Precipitate-free BGO crystals were grown under pulling rate of 2mm l hr which released the stress resulted from too hi어 Pulling rate, and from 6. IBi203·GeO2 batch composition obtained by addition of 0.1 mole Bi203 into Bi-deficient melts to fill up the deficiency resulted from gradual volatilization of Bi2O). The pale-yellow colored crystals had good quality in that dislocation density was less than 103pits/cm, and it also exhibited transmittance of 70% and optical activity of 23°/mm. and SAW velosity was measured 1700m/sec on 111 cut 110 propagating BGO crystals. The SAW filter with electrode thickness of 9.8um was fabricated by using the electron beam and dry etching technique, it makes Bi12GeO20 devices intersting for color TV IF with half device size.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.3
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• pp.211-231
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• 2001

Es gibt verschiedene Auffassungen $\"{u}ber$ die Formulierung der Ableitung, wobei nur die Suffixbildung als Ableitung einerseits gelten soll oder andererseits die Suffix- und $Pr\"{a}fixbildung$ zusammen als Ableitung gelten sollen. Hier wird die zweite Auffassung als Ableitung angesehen und danach $geh\"{o}rt$ auch die Zirkumfixbildung zur Ableitung. Das einzige Zirkumfix, mit dem die Substantive abgeleitet werden, ist ge-+-e und dessen Suffix kann gegebenenfalls nicht explizit $ausgedr\"{u}ckt$ werden. Diese Substantivableitung wird zuerst nach der Wortart der Basis und dann nach der Funktion oder Bedeutung $folgenderma{\ss}en$ klassifiziert: 1. Deverbale Substantive: 1) Abstrakta: Gefecht, $Ger\"{a}usch,\;Gest\"{o}ber$ - Wiederholung bzw. Dauer: $Gedr\"{o}hn$, Gekreisch, $Get\"{o}se$ - Pejorative Bewertung: Gejammer, Gerede, Geschreibe 2) Resultat bzw.Produkt: $Gem\"{a}lde$, Gewebe, Gewucher 3) Person bzw. Sache: $Gedr\"{a}nge,\;Gew\"{a}chs,\;Ger\"{o}ll$ 4) Instrumentalia: $Gebl\"{a}se,\;Gefa{\ss}$, Gestell b) Denominale Substantive: Kollektiva: Gehim, $Gel\"{a}nde$, Gerippe

• YAKHAK HOEJI
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• v.42 no.3
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• pp.330-335
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• 1998

Gastrodia elata (GE) is a oriental medicinal herb which has been used traditionally for the treatment of various brain diseases including convulsion and epilepsy. In orde r to examine the mechanism of anticonvulsive effect, we treated the methanol extract of GE (500mg/kg, P.0) to the pentylenetetrazole (PTZ)-induced convulsive rats. Methanol extracts of GE significantly inhibited (35%) the convulsion state as well as the level of lipid peroxidation (25%) in the brain. The ether fraction of methanol extracts among the others effectively ibhibited in vitro lipid peroxidation dose dependently ($5.O{\times}10^{-6}{\sim}2.O{\times}1O^{-5}g/ml$). The scavenging effect on hydroxy radicals was found in all the fractions of ether, butanol, and dichloromethane. These results suggest that the anticonvulsive effect of GE is possibly due to the antioxidative effects of the active components in GE.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.3-4
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• 2005

Germanium nanocrystals(NCs) were formed in the silicon dioxide($SiO_2$) on Si layers by Ge implantation and rapid thermal annealing process. The density and mean size of Ge-NCs heated at $800^{\circ}C$ during 10 min were confirmed by High Resolution Transmission Electron Microscopy. Capacitance versus voltage(C-V) measurements of MOS capacitors with single $Al_2O_3$ capping layers were performed in order to study electrical properties. The C-V results exhibit large threshold voltage shift originated by charging effect in Ge-NCs, revealing the possibility that the structure is applicable to Nano Floating Gate Memory(NFGM) devices.

• Korean Journal of Optics and Photonics
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• v.12 no.5
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• pp.394-400
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• 2001

We studied thermal diffusion properties diffusion properties of multi-layered Ge-Sb-Te alloy thin films for optical recording media by solving the thermal equation. Based on the numerical analysis of optical energy distribution and absorption inside multi-layered films including temperature gradient and heat transfer simultaneously, we proposed the optimum parameters of the input laser power and the multi-layer structure as follow. i) Input laser power is 18 mW, ii) laser exposure time is 60 ns, iii) the thicknesses of the lower and the upper ZnS-SiO$_2$are 140 nm and 20~30 nm respectively, and iv) thickness of Ge-Sb-Te recording film is 20 nm.

• Proceedings of the Korean Magnestics Society Conference
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• 2010.06a
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• pp.96-96
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• 2010

We report the proper resistance-area products in the single crystalline bcc CoFe/MgO tunnel contact on nondegenerate n-Ge desirable for efficient spin injection and detection at room temperature. The electric properties of the crystalline CoFe(5 nm)/MgO(1.5,2.0,2.5 nm)/n-Ge(001) tunnel contacts have been investigated by I-V-T and C-V measurements. Interestingly, the tunnel contact with the 2-nm MgO exhibits the ohmic behavior with low resistance-area products, satisfying the theoretical conditions required for significant spin injection and detection. This result is ascribed to the presence of MgO layer between CoFe and n-Ge, enhancing the Schottky pinning parameter as well as shifting the charge neutrality level.

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.27.1-27.1
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• 2007

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.209.1-209
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• 2000