• 제목/요약/키워드: SB

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황해와 한국연안해역 표층퇴적물중 Sb과 As의 농도분포특성 (The distribution characteristics of Sb and As in the surface sediment from the Yellow Sea and the coastal areas of Korea)

  • 황동운;;양한섭
    • 한국환경과학회지
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    • 제12권10호
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    • pp.1121-1129
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    • 2003
  • We report the distributions of Sb and As in the surface sediment of the Yellow Sea and the coastal areas of Korea. The mean concentrations of Sb and As range from 0.68 ppm to 1.01 ppm and from 7.4 ppm to 15.8 ppm, respectively, and show relatively the high concentrations at the coast of Weolseong in the East Sea for Sb and at the coast of Gadeok Island in the South Sea far As. This may be due to the anthropogenic input of these elements via river and atmosphere from industry complex and agriculture regions around the study areas. Because of the difference of clay to silt proportion, the correlation between silt plus clay contents and Sb, As in the coastal surface sediment of Korea is not shown, the concentrations of Sb and As vary widely for the sample in which the silt plus clay contents are the same. Therefore, we suggest that the distribution patterns of Sb and As in surface sediment of the Yellow Sea and the coastal areas of Korea are mainly controlled by the anthropogenic inputs and the sediment characteristics. On the other hand, the Sb concentrations are lower than those of the lowest effect level which is the standard of judgment for contamination, while the As concentrations are higher than those of the lowest effect level. This implies that the surface sediments of the Yellow Sea and the coastal areas of Korea are considerably contaminated for As.

Effect of Sesame Straw Biochar Application on Soil Physics and Nitrous Oxide Emission in Upland Soil

  • Kang, Se-Won;Cho, Ju-Sik;Kim, Hyun-Tae;Seo, Dong-Cheol;Moon, Sung-Dong
    • 한국토양비료학회지
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    • 제49권3호
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    • pp.259-264
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    • 2016
  • The effect of biochar application on soil physics and nitrous oxide ($N_2O$) emission from upland soil for broccoli cultivation was investigated. Sesame straw biochar (SB) was applied at amounts 0 (IF), 50 (SB50), 100 (SB100), 200 (SB200) kg $10a^{-1}$, respectively. SB addition to the upland soil decreased bulk density, and increased porosity and soil respiration. The $N_2O$ emission rates in all treatments were higher in the order of IF $${\geq_-}$$ SB50 > SB100 $${\geq_-}$$ SB200 treatments. Global warming potential in SB200 treatment decreased by 15.1% compared to IF treatment. Therefore, SB application in upland soil can improve soil physics and reduce $N_2O$ emission.

$Zn_7Sb_2O_{12}$ 첨가량이 ZnO 바리스터의 입자성장과 미세구조에 미치는 영향 (Effect of $Zn_7Sb_2O_{12}$ Content on Grain Growth and Microstructure of ZnO Varistor)

  • 김경남;한상목
    • 한국세라믹학회지
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    • 제30권11호
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    • pp.955-961
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    • 1993
  • Sintering behavior and microstructure development in the system ZnO-Bi2O3-CoO-Zn7Sb2O12 with Zn7Sb2O12 content(0.1mol%~2mol%) were studied. The pyrochlore phase was formed by the reaction of the Zn7Sb2O12 with Bi2O3 phase during heating (below 90$0^{\circ}C$). The formation temperature of the liquid phase (Bi2O3) was dependent on the Zn7Sb2O12 contents (about 74$0^{\circ}C$ for Bi2O3/Zn7Sb2O12>1 by the eutectic melting in the ZnOBi2O3 system, and about 110$0^{\circ}C$ for Bi2O3/Zn7Sb2O12 1 by the decomposition of pyrochlore phase). Hence, sintering behavior and microstructure development were determined virtually by the Bi2O3/Zn7Sb2O12 ratio, which were promoted by liquid (Bi2O3) phase and retarded by the pyrochlore (or spinel) phase. The grain growth of ZnO during sintering was sluggish with increasing Zn7Sb2O12 contents.

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A Study of the Electrical and Galvanomagnetic Properties of InSb Films

  • Bae, Chang-Hwan;Lee, Ju-Hee;Han, Chang-Suk
    • 대한금속재료학회지
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    • 제48권4호
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    • pp.353-356
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    • 2010
  • InSb thin films with a thickness of approximately 300 nm were prepared using single- and double-source vacuum evaporation methods and their structures and properties were investigated in terms of a heat treatment procedure. The double-source InSb films, prepared by the alternate stacking of In and Sb, were polycrystalline in structure and included small amounts of unreacted In and Sb phases. After annealing at elevated temperatures below the melting point of InSb (525$^{\circ}C$), the films changed into the InSb phase and were found to contain small amounts of unreacted In. The formation capability of the InSb compound was slightly lower for multilayer films than for single-layer films. The electrical and galvanomagnetic properties were found to be strongly related to the microstructures of the films. The maximum value of the Hall mobility and the magnetoresistance were determined to be $4.3{\times}10^3cm^2$/Vs and 70%, respectively, for the single-layer films, while these values for the alternately stacked films were respectively $2.9{\times}10^3cm^2$/Vs and 29% for the $[Sb(2.5)/In(2.5)]_{60}$ films, and $3.1{\times}10^3cm^2$/Vs and 10% for the $[Sb(150)/In(150)]_1$ films.

$Sb_2S_3$ 박막의 광도전특성 및 그 응용 (Photoconductive Property and Its Application of $Sb_2S_3$ Thin film)

  • 윤영훈;박기철;최규만;김기완
    • 대한전자공학회논문지
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    • 제23권5호
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    • pp.699-705
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    • 1986
  • Sb2S3 thin films were fabricated by vacuum evaporation of compound Sb2S3 at a pressure of 10**-5 torr. and in argon ambient. Then, their electrical and photoconductive properties were investigated. The Sb2S3 glass-layer showed maximum photosensitivity at the deposition rate of 250\ulcornersec, and Sb2S3 porous layer had mininum dielectric constant of 1.5 at the deposition rate of 0.3 um/sec and argon partial pressure of 0.2torr. Sb2S3 multi-layers were prepared at the different thickness ratio (B/A) to find the proper structural property suited for camera pick-up tube. Here, A is the sum of the thickness of Sb2S3 porous layer and Sb2S3 fine grain layer, and B is the thickness of Sb2S3 fine grain layer. As a result, photosensitivity had a peak value at the thickness ratio (B/A) of 60%.

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ON SB-RINGS

  • Chen, Huanyin
    • 대한수학회지
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    • 제45권3호
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    • pp.741-756
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    • 2008
  • In this paper, we introduce a new class of rings, SB-rings. We establish various properties of this concept. These shows that, in several respects, SB-rings behave like rings satisfying unit 1-stable range. We will give necessary and sufficient conditions under which a semilocal ring is a SB-ring. Furthermore, we extend these results to exchange rings with all primitive factors artinian. For such rings, we observe that the concept of the SB-ring coincides with Goodearl-Menal condition. These also generalize the results of Huh et al., Yu and the author on rings generated by their units.

박막 Hall 소자제작에 관한 연구(1) (A Study on the fabrication of thin film Hall device(1))

  • 조판상
    • 대한전자공학회논문지
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    • 제13권6호
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    • pp.16-19
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    • 1976
  • InSb-Sn 박막 Hall소자를 InSb-Sn분말을 flash흡착법으로 슬라이드 글래스 위에 흡착하여 만들었다. 이 소자를 자속계로 사용할 때 특성이 재현성이 좋고 직선성이 양호하였다. InSb-Sn thin film Hall device Was drepared by flash evaporation of InSb-Sn powder on the Slide qlass. The Characteristics Curve of this device showcd good linearity and reproducibility.

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Cold and Detonation Spraying of $TiB_2-Cu$ Nanocomposites

  • Lomovsky, O.I.;Dudina, D.V.;Korchagin, M.A.;Kosarev, V.F.;Klinkov, S.V.;Ulianitsky, V.Yu.;Kim, J.S.;Kwon, Y.S.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.680.2-680.2
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    • 2006
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Growing High-Quality Ir-Sb Nanostructures by Controlled Electrochemical Deposition

  • Nisanci, Fatma Bayrakceken
    • Journal of Electrochemical Science and Technology
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    • 제11권2호
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    • pp.165-171
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    • 2020
  • The electrochemical preparation and spectroscopic characterisation of iridium-antimony (Ir-Sb) species is important owing to their potential applications as nanostructure materials. Nanostructures, i.e. nanoflower and nanodisk, of Ir-Sb were electrodeposited on conductive substrates using a practical electrochemical method based on the simultaneous underpotential deposition (UPD) of Ir and Sb from the IrCl3 and Sb2O3 at a constant potential. Electrochemical UPD mechanism of Ir-Sb was studied using cyclic voltammetry and potential-controlled electrochemical deposition techniques. Herein, X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron and Raman spectroscopy were used to determine the morphological and structural properties of the electrochemically-synthesised Ir-Sb nanostructures.