• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.179-183
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• 2000

For a ground plane in high-temperature superconducting ramp-edge junction devices, YBa$_2$Cu$_3$O$_{7-{\delta}}$/SrTiO$_3$/YBa$_2$Cu$_3$O$_{7-{\delta}}$ multilayer structures were fabricated using pulsed laser deposition and ECR ion milling. Various process parameters were adjusted to enhance the device characteristics. By etching the STO layer to form a tapered edge of about 15$^{\circ}$ and in-situ RF plasma treatment of bottom YBCO surface prior to deposition of top YBCO, the top-to-bottom YBCO showed T$_c$ of 75${\sim}$80 K and I$_c$ of about 40 mA through holes. It was found that the deposition of bottom YBCO at a reduced laser repetition rate of 1Hz increased the T$_c$ of top YBCO to 79.9 K. The resistivity of 570 layer was about 10$^6$ ${\Omega}$cm at 60 K, which ensures good electrical isolation between successive YBCO layers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1404-1405
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• 2006

Transparent ZnO thin films were deposited on quartz substrates by a KrF pulsed laser deposition (PLD) technique with different process conditions such as substrate temperature ($T_s$) and oxygen ambient pressure ($pO_2$). Surface morphology, crystal structure, and electrical properties of the ZnO films were investigated in order to characterize their thin film properties. The pulsed laser deposited ZnO films showed highly c-oriented crystalline structures depending on the process conditions: the highest FWHM (Full Width Half Maximum) value of (002) peak was observed for the ZnO film prepared at $T_{s}=550^{\circ}C$, $pO_2$=5mTorr and laser fluence of $2J/cm^2$.

• Progress in Superconductivity
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• 제2권2호
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• pp.65-70
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• 2001

$Pb/Bi_2Sr_2CaCu_2O_{8+\delta}$-single-crystal junctions with the tunneling direction along the c axis of the crystal were fabricated to obtain an s-wave-superconductor/d-wave-superconductor Josephson junctions. The tunneling R (T) curves and current-voltage characteristics show distinct features which can be explained only under the assumption that the order parameter of high-$T_c/Bi_2Sr_2CaCu_2O_{8+{\delta}}$ superconductors has a pure d-wave symmetry, which is in contrast to the case of $YBa_2Cu_3O_{7+{\delta$}}$erconductors where a minor s-wave component is also present..

• 한국분무공학회지
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• 제2권4호
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• pp.47-53
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• 1997

By using a premixed laminar burner, the effect of mixture component on laminar burning velocity($S_L$) was investigated. The following was made clear ; (1)As the humidity$(H_2O)$, $CO_2$ and Ar in mixture is increased, $S_L$ decreased in proportion to quantity of those dilution gases. (2) The heat reaction theory says that mean thermal conductivity $(\lambda_m)$, specific heat $(C_{pm})$ of mixture and adiabatic flame temperatures $(T_b)$ affect $S_L$. As a result of theoretical analysis, the effect of $\lambda_m\;and\;C_{pm}$ on $S_L$ is less than 1/25 of the effect of $T_b$, so the effect of $\lambda_m\;and\;C_{pm}$ can be ignored. (3) From experimental results, it was confirmed that $\ln(S_L)$ is proportional to $(1/T_b)$, that is, the effect of $H_2O$ on $S_L$ is mainly caused by changes of $T_b$. This conclusion was verified by the fact increases of $H_2O,\;CO_2$ and Ar decrease the intensity of radiation typical $C_2$, CH, and OH in the same manner.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.210-213
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• 1999

Magnetoresistance and magnetization of Sr$_{l-x}K_xBiO_3$ were both measured as functions of temperature and magnetic field. Resistivity goes to zero at T=10.1K and the overall superconducting transition behavior under applied magnetic fields is similar to that of other BiO based superconductors. Also, below T<5K we have observed the reappearance of finite resistivity with a power law temperature dependence( ${\rho}$ ${\sim}$T$^1$); the reentrant superconducting transition of resistivity. Contrary to the Josephson weak link effect in polycrystalline samples, which gives the depression of the superconducting state with increasing electrical current or magnetic field, the superconducting state for T<5K is resumed by applying a higher current or magnetic field. Magnetic susceptibility( ${\chi}$ ) of Sr$_{l-x}K_xBiO_3$ for T<5K also shows similar trends to that observed in transport measurements: increase of ${\chi}$ (paramagnetic-like behavior) at a low magnetic fields(B=50 Oe) and, the resumption of perfect diamagnetism at high fields.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1997년도 제13회 학술발표회 논문개요집
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• pp.162-162
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• 1997

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 디스플레이 광소자 분야
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• pp.145-147
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• 2000

The secondary electron emission coefficient y of MgO single crystal according to the gas mix-ture ratio of Xe, $N_2$ to Ne have been investigated by $\gamma$-focused ion beam system. It is found that the MgO single crystals of (111) crystallinity has the highest $\gamma$ for operating Ne(Xe) ions ranging from 50eV to 200eV throughout this experiment. And it is found that the $\gamma$ for gas mixtures are much smaller than pure Ne ions.

• 한국가금학회지
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• 제28권3호
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• pp.239-244
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• 2001

육계를 13주간 사육하면서 5주령부터 시험사료를 급여한 후 세포표면항원의 발현과 탐식세포에서 생성되는 $O_{2}$ -와 $H_{2}$ $O_{2}$ 에 미치는 영향 그리고 항원 특이적인 항체 생성에 미치는 영향을 측정하기 위하여 아마종실과 항산화제 무첨가구 ($T_{1}$), 아마종실만을 혼합한 사료 ($T_{2}$), 아마종실에 ;$\alpha$ -tocopherol 첨가구 ($T_{3}$ )와 아마종실에 $\alpha$ -tocopherol과 셀레늄 첨가구 ($T_{4}$ )를 육계에 급여한 바, 시험사료를 2주간 급여시 호중구 및 macrophages와 같은 탐식 세포의 $O_{2}$ -와 $H_{2}$ $O_{2}$ 생성 능력은 시험구 ($T_{2}$ , $T_{3}$ ,$T_{4}$ )들이 $T_{1}$ 구보다 증가하였으나 유의차는 없었다. 시험사료를 4주간 급여시 $O_{2}$ -와 $H_{2}$ $O_{2}$ 생성 능력은 $T_{2}$ 구와 $T_{1}$ 구간 큰 차이는 없었으나 $T_{3}$ 구와 $T_{4}$ 구의 $O_{2}$ -생성능력은 $T_{1}$ 구보다 각각 6%와 18%가 증가하였고, $H_{2}$ $O_{2}$ 생성 능력은 각각 9.5%와 10.9%가 증가하였다. 시험사료를 8주간 급여한 후 $T_{3}$ 와 $T_{4}$ 구의 $O_{2}$ -생성능력은 $T_{1}$ 구에 비하여 50%가 넘은 유의성 (P<0.01) 있는 강력한 증가가 있었고, $H_{2}$ $O_{2}$ 생성능력은 각각 6.6%와 9.3%가 증가하였다.

• 한국가정과학회지
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• 제1권2호
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• pp.89-99
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• 1998

This study was carried out to investigate some antioxidative effects of stewed pumpkin juice (SPJ) and the SPJs added with ginger (SPJ-G), onion (SPJ-O), jujube (SPJ-J) or boxthorn (SPJ-B), respectively, on the lipid oxidation of soybean oil (S) and mackerel pike boiled ground (MPBG). Antioxidative substances of SPJ were extracted by using the two solvent layers of n-hexane:acetone (1:1)(H) and methanol:water (7:3)M. The antioxidative effects of the extracts were observed by the peroxide value (P.O.V.) and thiobabituric acid (T.B.A.) value. The P.O.V. and T.B.A. value of two solvent extracts of S and MPBG showed significantly lower than those of S and MPBG. The SPJ showed very distingnished antioxidative effects. It was considered that melanoidine extracted by using methanol:water (7:3) solvent as well as carotenoid extracted by using n-hexane:acetone (1:1) solvent had an antioxidative effect. During storage, T.B.A. value of MPBG significantly increased, while that of MPBG-SPJ significantly decreased more than that of MPBG. T.B.A. value of MPBG-SPJs decreased much than that of MPBG-SPJ, SPJ-O, SPJ-G, SPJ-J and SPJ-B, in order of abundance, showed higher level of antioxidative effects than SPJ. (Korean J Human Ecology 1(2):89∼99, 1998)

• 한국전기전자재료학회논문지
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• 제14권6호
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• pp.475-480
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• 2001

Glasses in he system CuO-P$_2$O$_{5}$ -Nb$_2$O$_{5}$ -Nb$_2$O$_{5}$ -V$_2$O$_{5}$ were prepared by a press-quenching method on the copper plate. the glass-ceramics from these glasses were obtained by post-heat treatment, and the crystallization behavior and DC conductivities were determined. The conductivities of the glasses were range from 10$^{-6}$ s.$cm^{-1}$ / at room temperature ,but the conductivities of the glass-ceramics were 10$^{-3}$ s.$cm^{-1}$ / increased by 10$^3$ order. The crystalline product in the glass-ceramics was CuV$_2$O$_{6}$ . the crystal growth of CuV$_2$O$_{6}$ phase increased with heat-treatment conditions. The linear relationship between il($\sigma$T) and T$^{-1}$ suggested that the electrical conduction in the present glass-ceramics would be due to a small polaron hopping(SPH) mechanism.