• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1995.05a
• /
• pp.66-72
• /
• 1995

Microstructural features of laser irradiated bulk target which consists of GeSbTe interrmertallic compounds were examined by analytical microscopy. It was found that in addition to vaporization, a liquid expulsion due to laer-material interatction is main contribution of materials removal in the sintered GaSbTe targets, The morphological change is qualitatively discussed in the present article.

• Proceedings of the Optical Society of Korea Conference
• /
• 1990.02a
• /
• pp.242-247
• /
• 1990

By self-homodyne method we measured the relative phase fluctuation of a light wave. Balanced detection system can eliminate local oscillator excess noise and multiport detection makes it possible ot measure the phase change of the signal beam. Deriving the SB(Signal Beam) and the LO(Local Oscillator) from the same laser source, we find the SB maintain constant phase relative to that of the LO. We have introduced a phase fluctuation in the SB by modulating the beam path of the SB. The measured phase fluctuation agreed well with the predicted one, thereby we confirmed the reliability of our system.

• The Korean Journal of Quaternary Research
• /
• v.21 no.2
• /
• pp.56-57
• /
• 2007

• Archives of Pharmacal Research
• /
• v.27 no.9
• /
• pp.915-918
• /
• 2004

By bioassay-guided separation, an already known saponin, Pulsatilla saponin D was isolated from the root of Pulsatilla koreana Nakai as a antitumor component when evaluated by in vivo antitumor activity as well as in vitro cytotoxic activity test. It showed potent inhibition rate of tumor growth (IR, 82％) at the dose of 6.4 mg/kg on the BDF1 mice bearing LLC cells.

• Journal of the Korean Ceramic Society
• /
• v.31 no.2
• /
• pp.185-193
• /
• 1994

Effect of Sb2O3 addition on microstructure and the PTCR characteristic was investigated. The range of the Sb2O3 content and the sintering temperature showing semiconducting and PTCR characteristic, were 0.05~0.125 mol%, and over 130$0^{\circ}C$, respectively. We found that PTCR characteristic, that is, room-temperature resistivity and specific resistivity ration were dependent on the microstructure.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.30A no.6
• /
• pp.31-37
• /
• 1993

InSb thin films were fabricated by zone melting recrystallization of In/Sb multilayered thin films prepared by sequential evaporation. Unreacted metal phase or dispersed metal precipitates lowered the electron mobility and the electron mobility increased with development of (111) prefered orientation. Properties of the film could be controlled by changing mzximum temperature and scanning speed, and the electron mobility as high as 12, 000 cm $^2$/Vsec could be obtained under the optimized conditions.

• Proceeding of EDISON Challenge
• /
• 2013.04a
• /
• pp.234-237
• /
• 2013

본 논문에서는 실리콘 나노선 구조를 갖는 모스펫 (Metal-Oxide-Semiconductor Field Effect Transistors, MOSFETs)과 쇼트키 장벽 트랜지스터 (Schottky-Barrier(SB) MOSFETs, SB-MOSFETs)의 전기적인 특성을 양자역학적 시뮬레이션 계산을 통해 비교하였다. 쇼트키 장벽 높이 (Schottky Barrier, ${\phi}_{SBH}$)에 따른 SB-MOSFETs의 터널링 특성을 분석하고, 소스/드레인 (S/D) 길이가 변함에 따라 달라지는 S/D 저항을 계산하여, ${\phi}_{SBH}$가 0eV인 SB-MOSFETs의 On과 Off $I_D$ 비율 ($I_{ON}/I_{OFF}$)이 MOSFETs보다 개선될 수 있음을 보였다.

• Journal of Life Science
• /
• v.19 no.9
• /
• pp.1314-1320
• /
• 2009

Histone deacetylase inhibitor (HDACI) is a new promising candidate as an antineoplastic agent for the treatment of solid and hematologic malignancies. In order to evaluate cell death and to elucidate the related mechanism(s) in NSCLC cells after HDACI, sodium butyrate (SB), a representative HDACI, was used to treat H460 cells for 48 hrs. SB exposure resulted in a significant reduction of cell viability at concentrations below 7.5 mM, and about 50% of cell death occurred at 20 mM. The types of cell death induced by SB were both apoptosis and necrosis, evaluated by Annexin-V staining combined with propidium iodide. SB treatment significantly evoked G2/M cell cycle arrest and subsequently induced cell death with caspase-dependent manner. While ERK protein content was not altered after SB, phosphorylated forms of ERK were markedly reduced. Taken together, SB is significantly able to induce cell death in NSCLC cell line H460, and it is suggested that the reduction of ERK phosphorylation might be closely involved in the cancer cell death mechanism initiated by HDACI.

• Korean Journal of Materials Research
• /
• v.22 no.12
• /
• pp.675-681
• /
• 2012

We aimed to examine the co-doping effects of 1/6 mol% $Mn_3O_4$ and 1/4 mol% $Cr_2O_3$ (Mn:Cr = 1:1) on the reaction, microstructure, and electrical properties, such as the bulk defects and grain boundary properties, of ZnO-$Bi_2O_3-Sb_2O_3$ (ZBS; Sb/Bi = 0.5, 1.0, and 2.0) varistors. The sintering and electrical properties of Mn,Cr-doped ZBS, ZBS(MnCr) varistors were controlled using the Sb/Bi ratio. Pyrochlore ($Zn_2Bi_3Sb_3O_{14}$), ${\alpha}$-spinel ($Zn_7Sb_2O_{12}$), and ${\delta}-Bi_2O_3$ (also ${\beta}-Bi_2O_3$ at Sb/Bi ${\leq}$ 1.0) were detected for all of the systems. Mn and Cr are involved in the development of each phase. Pyrochlore was decomposed and promoted densification at lower temperature on heating in Sb/Bi = 1.0 system by Mn rather than Cr doping. A more homogeneous microstructure was obtained in all systems affected by ${\alpha}$-spinel. In ZBS(MnCr), the varistor characteristics were improved dramatically (non-linear coefficient, ${\alpha}$ = 40~78), and seemed to form ${V_o}^{\cdot}$(0.33 eV) as a dominant defect. From impedance and modulus spectroscopy, the grain boundaries can be seen to have divided into two types, i.e. one is tentatively assigned to ZnO/$Bi_2O_3$ (Mn,Cr)/ZnO (0.64~1.1 eV) and the other is assigned to the ZnO/ZnO (1.0~1.3 eV) homojunction.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.13 no.5
• /
• pp.254-259
• /
• 2003

In the fabrication process of transparent conducting thin films of the ATO (antimony-doped tin oxide) on a soda lime glass substrate by a sol-gel dip coating method, the effects of the $SiO_2$ buffer layer formed on the substrate and $N_2$ annealing treatment were investigated by XPS (X-ray photoelectron spectroscopy) analysis. Optical transmittance and electrical resistivity of the 400 nm-thick ATO thin films which were deposited on $SiO_2$ buffer layer/soda lime glass and then annealed under nitrogen atmosphere were 84 % and $5.0\times 10^{-3}\Omega \textrm{cm}$ respectively. The XPS analysis confirmed that a $SiO_2$ buffer layer inhibited Na ion diffusion from the substrate, resulting in prohibiting the formation of a secondary phase such as $Na_2SnO_3$ and SnO and increasing Sb ion concentration and ratio of $Sb^{5+}/Sb^{3+}$ in the film. And it was also found that $N_2$ annealing treatment leads to the reduction of $Sn^{4+}$as well as $Sb^{5+}$ however the reduction of $Sn^{4+}$ is more effective and therefore consequently results in decrease in the electrical resistivity to produce an excellent electrical properties of the film.