• Journal of the Korean Ceramic Society
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• v.29 no.9
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• pp.681-688
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• 1992

Ultrafine Si3N4 and Si3N4+SiC mixed powders were synthesized through thermal plasma chemical vapor deposition(CVD) using a hybrid plasma, which was characterized by the supersposition of a radio-frequency plasma and arc jet. The reactant SiCl4 was injected into an arc jet and completely decomposed in a hybrid plasma, and the second reactant CH4 and/or NH3 mixed with H2 were injected into the tail flame through double stage ring slits. In the case of ultrafine Si3N4 powder synthesis, reaction efficiency increased significantly by double stage injection compared to single stage one, although crystallizing behaviors depended upon injection speed of reactive quenching gas (NH3+N2) and injection method. For the preparation of Si2N4+SiC mixed powders, N/C composition ratio could be controlled by regulating the injection speed of NH3 and/or CH4 reactant and H2 quenching gas mixtures as well as by adjusting the reaction space.

• Biomedical Science Letters
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• v.10 no.3
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• pp.219-230
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• 2004

This experiment was performed to examine the in vitro and in vivo affects of the two different haplotype strains of mice, BALB/c and C3H/HeN infected with Echinostoma hortense, and the manifestation of the profiles of cytokine in the splenocytes. In the in vitro experiment, the two mice's splenocytes were divided and stimulated with antigen of crude extracts and the antigen of excretory and secretory products of an adult warm and the manifestation of cytokine mRNA was verified with RT-PCR. As a result, the two different strains of mice both strongly manifested the Th2 cytokine rather than the Thl cytokine and in the case of the Th2 cytokine, the BALB/c mice manifested more strongly than the C3H/HeN mice. In the experiment using the ELISA method, the protem cytokine manifestation had the same result as the mRNA experiment. In the in vivo experiment, the mice was infected via oral route with the metacercaria of the Echinostoma hortense and the manifestation of cytokine was verified by RT-PCR and ELISA and the results were the same as the in vitro experiment. Therefore, in the two strains of BALB/c and C3H/HeN, the C3H/HeN showed a higher susceptivity to the Echinostoma hortense.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.110.2-110.2
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• 2011

일본 Sanyo 사에 의해서 획기적으로 HIT 태양전지가 개발된 바 있다. 이러한 HIT 태양전지는 기존의 확산-접합 Si 태양전지에 비해서 저비용 고효율의 장점을 갖는다: 22% 이상의 변환효율, $200^{\circ}C$ 이하의 공정온도, 낮은 태양전지 온도 의존도, 높은 개방전압. 한편 Sanyo사의 HIT 태양전지는 n-형 Si 웨이퍼를 이용한 반면에, 최근 미국 National Renewable Energy Laboratory는 p-형 Si 웨이퍼를 이용해서 변환효율 19% 대의 HIT 태양전지를 개발한 바 있다. 그 동안 지속적으로 p-형 Si HIT 태양전지를 고효율화하기(< 22%) 위해서 많은 노력이 진행되어 왔지만 이와 같은 노력에도 불구하고 아직 p-형 HIT는 n-형 HIT 태양전지에 비해서 다소 성능면에서 떨어져 있다. 본 연구는 n- 및 p-형 실리콘 웨이퍼로 구성된 HIT 태양전지의 물리적인 차이점에 초점을 맞추고, 결정 및 비정질 실리콘 층의 역할에 대해서 연구하였다. 특히 태양전지 효율을 향상시키는 요소들로서 결정 실리콘의 불순물 준위(n- 및 p-형) 또는 비저항, 비정질 실리콘으로 구성된 emitter 층, intrinsic 층, 경계면이 고려되었다. 그리고 이러한 요소들이 HIT 태양전지에 미치는 영향을 조사하기 위해서 AMPS-1D 컴퓨터 프로그램을 사용하였고, 이를 통해서 HIT 태양전지의 결정 및 비정질 실리콘 층의 역할을 물리적 정량적으로 분석하였다. 본 연구에 적용되는 HIT는 ITO/a-Si:H(p+)/a-Si:H(i)/c-Si(n)/a-Si:H(i)/a-Si:H(n+) 및 ITO/a-Si:H(n+)/a-Si:H(i)/c-Si(p)/a-Si:H(i)/a-Si:H(p+)의 구조로서 다음과 같은 태양전지 특성을 갖는다: n-형 HIT의 경우, fill factor ~ 0.78, 단락전류밀도 ~ 38.1 $mA/cm^2$, 개방전압 0.74 V, 변환효율 22.3 % (그리고 p-형 HIT의 경우, fill factor ~ 0.76, 단락전류밀도 ~ 36.5 $mA/cm^2$, 개방전압 0.69 V, 변환효율 19.4 %).

• Journal of the Korean Chemical Society
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• v.14 no.2
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• pp.193-199
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• 1970

Further validity of the significant structure theory has been tested by calculating the viscosities of binary mixtures-three pairs of $C_6H_6(1)+C_6H_{12}\;(2),\;CCI_4\;(1)+C_6H_6{2}and\l;CCI_4(1)+C_6H_{12}(2)$-and also by calculating the viscosities of n-$C_5H_{12}\;and\;n-C_6H_{14}$ in the pressure range of 1 bar to 4000 bars. The results are quite satisfactory for both cases and provide another evidence for the validity of the significan structure theory.

• Bulletin of the Korean Mathematical Society
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• v.34 no.2
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• pp.173-184
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• 1997

An n-dimensional complex space form $M_n(c)$ is a Kaehlerian manifold of constant holomorphic sectional curvature c. As is well known, complete and simply connected complex space forms are a complex projective space $P_n C$, a complex Euclidean space $C_n$ or a complex hyperbolic space $H_n C$ according as c > 0, c = 0 or c < 0.

• Journal of the Korean Mathematical Society
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• v.32 no.4
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• pp.835-848
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• 1995

Let $M_n$(c) be an n-dimensional complete and simply connected Kahlerian manifold of constant holomorphic sectional curvature c, which is called a complex space form. Then according to c > 0, c = 0 or c < 0 it is a complex projective space $P_nC$, a complex Euclidean space $C^n$ or a complex hyperbolic space $H_nC$.

• Communications of the Korean Mathematical Society
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• v.9 no.2
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• pp.369-383
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• 1994

A complex n-dimensional Kahler manifold of constant holomorphic sectional curvature c is called a complex space form, which is denoted by $M_{n}$ (c). A complete and simply connected complex space form consists of a complex projective space $P_{n}$ C, a complex Euclidean space $C^{n}$ or a complex hyperbolic space $H_{n}$ C, according as c > 0, c = 0 or c < 0.(omitted)

• Journal of the Korean Chemical Society
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• v.20 no.1
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• pp.3-14
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• 1976

The crystal structure of alicylaldehyde-4-piperidinothiosemicarbazone, $C_{13}H_{l7}N_3OS$, has been determined by single crystal X-ray analysis. The crystals are orthorhombic, space group $P2_12_12_1$, with unit cell dimensions a = 6.52(2), b = 13.42(4), c = 14.92(4)${\AA}$. There are four formular units in a unit cell. The structure was solved by the heavy atom method and refined by isotropic block diagonal least-squares methods to a final R value of 0.10 for 1019 observed reflections. The oxygen atom of the hydroxyl group is involved in two hydrogen bonds, one as donor in the intramolecular O-H${\cdots}$N hydrogen bond and the other as acceptor in the intermolecular N-H${\cdots}$O hydrogen bond, the distances of the hydrogen bonds 2.56 and 3.00${\AA}$ respectively.The molecules are joined into infinite columns by the N-H${\cdots}o$O hydrogen bonds which form spirals along the two fold screw axis parallel to the a axis. The molecular columns are held together by van der Waals forces.

• Journal of IKEEE
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• v.22 no.4
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• pp.1226-1229
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• 2018

We investigated the improvement of surface roughness and states after high temperature annealing using reduced-graphene oxide (r-GO) capping layer on ion-implanted 4H-SiC epitaxial layer. The specification of the 4H-SiC wafer grown on n-type $4^{\circ}$ off-axis 4H-SiC was $10{\mu}m$-thick and n-type epitaxial layer with a dose of $1.73{\times}10^{15}cm^{-2}$. The $n^+$ region were formed by multiple nitrogen ion-implantations and r-GO capping layer was produced by spray coating method. AFM measurements revealed that RMS value of the sample capped with r-GO was tenfold decrease compared to the sample without r-GO capping. The improvement of surface states was also verified by the improvement of leakage current level.

• Journal of the Korean institute of surface engineering
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• v.26 no.1
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• pp.11-21
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• 1993

The relationship between the amount of deposited-Zn and the adhesion of Zn film has beend investigated. This study changed the mild steel substrate temperature range of $100^{\circ}C$~$250^{\circ}C$, with the aim of studying the adhesion of Zn film coated by PVD on substrates in 10-2~10-3torr and deoxidant gas atmospheres 50%H2~50%N2 and 75%H2+25%N2. The result revealed that the adhesion of Zn film was remarkably good in a 75% H2+25%N2 gas atmosphere as well as deoxidant time was short, and with increasing the substrate tempera-ture up to $250^{\circ}C$. Whiled the amount of deposition tended to increase linearly with time at constant evaporation temperature. It was almost constant when the substrate temperature was lower than $200^{\circ}C$, slightly decreased between $200^{\circ}C$ and $250^{\circ}C$ and significantly decreased at $300^{\circ}C$.