• Title/Summary/Keyword: SB

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Improved Switching Properties of Sb-doped Ge-Se-Te Material (Sb-doping에 의한 Ge-Se-Te의 개선된 스위칭 특성)

  • Chung, Hong-Bay;Nam, Ki-Hyun;Koo, Sang-Mo
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1260_1261
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    • 2009
  • A detailed investigation and structure of tested samples are clearly presented. As a reference, $Ge_1Se_1Te_2$/Sb only sample was also investigated. We used compound of Ge-Se-Te material for phase-change cell. Actually, the performance properties have been improved surprisingly then conventional Ge-Sb-Te. However, crystallization time was as long as ever for amorphization time. We conducted this esperiment in order to solve that problem by doping-Sb.

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Semiconducting Behavior in the Polymeric Zintl Phase Material $K_2Ga_2Sb_4$

  • Wu, Biao;Birdwhistell, Teresa L.T.;Jun, Moo-Jin;O'Connor, Charles J.
    • Bulletin of the Korean Chemical Society
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    • v.11 no.5
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    • pp.464-466
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    • 1990
  • A ternary Zintl phase material of the formula $K_2Ga_2Sb_4$ has been prepared directly from reaction of the elements following a high temperature procedure. The compound consists of potassium ions and planar ribbons of $(Ga_2Sb_4^{-2})_{\infty}$ consisting of five membered $[Ga_2Sb_3]$ rings bridged by Sb atoms. The variable temperature specific resistivity measurements show the material to be an intrinsic semiconductor.

Effects of Evaporation Processes and a Reduction Annealing on Thermoelectric Properties of the Sb-Te Thin Films (증착공정 및 환원분위기 열처리가 Sb-Te 박막의 열전특성에 미치는 영향)

  • Bae, Jae-Man;Kim, Min-Young;Oh, Tae-Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.17 no.4
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    • pp.77-82
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    • 2010
  • Effects of evaporation processes and a reduction annealing on thermoelectric properties of the Sb-Te thin films prepared by thermal evaporation have been investigated. The thin film evaporated by using the powders formed by crushing a $Sb_2Te_3$ ingot as an evaporation source exhibited a power factor of $2.71{\times}10^{-4}W/m-K^2$. The thin film processed by evaporation of the mixed powders of Sb and Te as an evaporation source showed a power factor of $0.12{\times}10^{-4}W/m-K^2$. The thin film fabricated by coevaporation of Sb and Te dual evaporation sources possessed a power factor of $0.73{\times}10^{-4}W/m-K^2$. With a reduction annealing at $300^{\circ}C$ for 2 hrs, the power factors of the films evaporated by using the $Sb_2Te_3$ ingot-crushed powders and coevaporated with Sb and Te dual evaporation sources were remarkably improved to $24.1{\times}10^{-4}W/m-K^2$ and $40.2{\times}10^{-4}W/m-K^2$, respectively.

Effect of V and Sb on the Corrosion Behavior and Precipitate Characteristics of Zr-based Alloys for Nuclear Fuel Cladding (핵연료 피복관용 Zr합금의 부식거동 및 석출물 특성에 미치는 V, Sb 첨가의 영향)

  • Jeon, Chi-Jung;Kim, Seon-Jin;Jeong, Yong-Hwan
    • Korean Journal of Materials Research
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    • v.8 no.12
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    • pp.1099-1109
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    • 1998
  • To investigate the effect of V and Sb on the corrosion behavior of Zr- based alloys, corrosion tests were performed on 6 kinds of Zr alloys in an autoclave at $360^{\circ}C$ for 100 days. The transition of the corrosion rate occurred in the sample containing 0.1wt.%V after 10 days but did not occur in the samples containing 0.2wt.%V and 0.4wt.%V. The corrosion resistance of V containing alloys increased with increasing V contents from 0.1 to 0.4wt.% and the alloys containing 0.4wt.%V showed the best corrosion resistance. In the ternary alloys containing 0.1wt.%Sb and 0.4wt.%Sb, the corrosion rate increased significantly from the short exposure time. It was observed that the optimal Sb content for corrosion resistance was 0.2wt.%. The size and volume fraction of precipitates increased with increasing V and Sb contents. The superior corrosion resistance was observed in the Zr alloy having precipitate size of 0.11-0.13$\mu\textrm{m}$. From the result of corrosion behavior and the obserbation of precipitates, the optimal size of the precipitate appear to control the electron conduction in the cathodic reaction and play an important role in maintaining a stable oxide microstructure.

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Pharmacokinetics of Anticancer Agent SB-31 in Rats & Rabbits and the Cardiovascular Effect on the Isolated Perfused Rat Heart & Blood Coagulation (SB-31의 Glycyrrhizin을 지표로 한 Rat과 Rabbit에서의 약물동태 및 심혈관계에 대한 효과 연구)

  • Kang, Won Ku;Park, Yong Soon;Lee, Dong Heum;Kwon, Kwang Il
    • Korean Journal of Clinical Pharmacy
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    • v.8 no.2
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    • pp.122-132
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    • 1998
  • SB-31 which contains Pursatilla, Licoris and Ginseng extracts was recently proved as an anticancer agent. In a preclinical effort to be applied this drug to human, pharmacokinetics of SB-31 was carried out in rats and rabbits. Glycyrrhizin(GZ), a saponin of Licoris was used as a standard ingradient for the pharmacokinetics of SB-31. The rat's blood, bile and urine samples were serially collected in femoral vein, common bile duct and bladder, respectively, after bolus i.v. injection at a dose of 1 or 1/5 ampul/rat and rabbit's blood samples from the marginal ear vein at a dose of 1 or 3 amp./rabbit. GZ and glycyrrhetic acid(GA), a major metabolite of GZ in the physiological samples were analysed by HPLC with UV detection. The decline of GZ in plasma concentration was generally biexponential at each dose. GZ was almost completely recovered in bile within 18 hour. GA wasn't detected in the samples with UV detector. In the rat, Vss and Kel at a dose of 1 and 1/5 ampul of SB-31 were $98.06\pm6.07\;ml,\;0.33\pm0.05\;hr^{-1}\;and\;65.46\pm11.19\;ml,\;0.68\pm0.25\;hr^{-1}$, respectively. Those in rabbits at a dose of 3 and 1 ampul of SB-31 were $235.24\pm30.72\;ml,\;0.13\pm0.36\;hr^{-1}\;and\;341.32\pm28.58\;ml,\;0.27\pm0.04\;hr^{-1}$, respectively. 'WinNonlin' was utilized for the compartmental analysis. A two-compartment model was chosen as the most appropriate pbarmaco-kinetic model. The data were best described by using a weighting factor of $1/y^2$. To evaluate the effect of SB-31 on cardiovascular system, serially diluted SB-31 was directly injected into coronary artery in the isolated perfused rat heart and the effect of PSF, PSH, saponins of Pursatilla, and SB-31 on PT, APTT of healthy human plasma was examined. Except the positive inotropic effect of ten times diluted solution of SB-31, there was no significant effect on LVDP, (- dp/dt)/(+dp/dt), heart rate and coronary flow in comparision with that of vehicle. SB-31 had no effect on PT but slightly delayed APTT about $6.9{\sim}11.5\%$. There was no significant effect of PSF and PSH on PT & APTT. Conclusively, SB-31 did not show any notable toxic effects on cardiovascular system.

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Atomic Arrangement of Ordered Phase in $GaAs_{0.5}Sb_{0.5}$ Epilayer ($GaAs_{0.5}Sb_{0.5}$ 에피층의 규칙상의 원자 배열)

  • Ihm, Yeong-Eon
    • Korean Journal of Materials Research
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    • v.3 no.6
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    • pp.678-683
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    • 1993
  • Atomic arral1gement of ordered phase in $GaAs_{0.5}Sb_{0.5}$ epilayer was studied by observation of selected area diffraction patterns and high resolution images. The epilayer was grown on untilted (001) GaAs substrate at $580^{\circ}C$ by molecular beam epitaxy(MBE). A 1/2(111) type long-range ordered phase is formed in the epilayer. Atomic arrangement of the ordered phase is described as an alternative stacking of As-rich and Sb-rich {111} planes in group V sublattice. Space group of the ordred structure belongs to R3m, and unit cell of the ordered structure is rhombohedral.

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A Simple and Quick Chemical Synthesis of Nanostructured Bi2Te3, Sb2Te3, and BixSb2-xTe3

  • Kim, Hee-Jin;Lee, Ki-Jung;Kim, Sung-Jin;Han, Mi-Kyung
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1123-1127
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    • 2010
  • We report a simple and quick route for the preparation of high-quality, nearly monodisperse $Bi_2Te_3$, $Sb_2Te_3$, and $Bi_xSb_{2-x}-Te_3$ nanocrystallites. The reactions of bismuth acetate or antimony acetate with Te in oleic acid result in pure phase of $Bi_2Te_3$ or $Sb_2Te_3$ nanoparticles, respectively. Also, ternary $Bi_xSb_{2-x}Te_3$ nanoparticles were successfully synthesized using the same method. The size and morphology of the nanoparticles were controlled by varying the stabilizing agents. The as-prepared nanoparticles are characterized by X-ray diffraction, scanning electron microscope, and high-resolution transmission electron microscope using an energy dispersive spectroscopy.