• Title/Summary/Keyword: Sb addition

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A New Method to Control the Coverage of Irreversibly Adsorbing Sb on Au Electrode

  • 류호열;이충균
    • Bulletin of the Korean Chemical Society
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    • v.18 no.4
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    • pp.385-389
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    • 1997
  • We report on the development of a new method to control the coverage of a metal film prepared with immersion method. An Sb species in solution adsorbed irreversibly at an open circuit potential (∼0.2 V) as an oxygenous Sb(Ⅲ) on a clean Au electrode, and the adsorbates showed voltammetric features in the potential range from 0.1 V to - 0.4 V. The full coverage of the Sb adsorbates was ∼0.45. On the contrary, the Sb species in solution did not adsorb at all on iodine-covered Au electrode surfaces, when the iodine coverages were more than 0.25. As the iodine coverage decreased below 0.25, however, the irreversible adsorption of Sb took place and the coverage of Sb increased accordingly. This electrochemical behavior has been interpreted as the penetration of the adsorbing Sb species in solution through open spaces among the iodine adlattices of coverages less than 0.25. With the manipulation of the iodine coverage, the controllable range of Sb coverage was from 0 to 0.45, i.e. the full coverage of Sb. In addition, the reversible deposition of Sb on an iodine-saturated Au electrode with voltammetric scan has been observed, which is contrasted with the adsorptive behavior of Sb on the clean Au electrode.

Effect of $ M_2O_3$ on the Sinterbility and Electrical Conductivity of $ZrO_2(Y_2O_3)$ System(II) : Ceramics of the $ZrO_2(Y_2O_3)$-$Sb_2O_3)$ System ($ZrO_2(Y_2O_3)$계 세라믹스의 소결성과 전기전도도에 대한 $ M_2O_3$의 영향 (II): $ZrO_2-Y_2O_3-Sb_2O_3$계 세라믹스)

  • 오영재;정형진;이희수
    • Journal of the Korean Ceramic Society
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    • v.23 no.6
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    • pp.37-44
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    • 1986
  • Yttria-antimonia-stabilized zirconia was investigated with respect to the amount of $Sb_2O_3$ addition in the range of 0.5~5mole% to the base composition of $(ZrO)_{0.92}(Y_2O_3)_{0.08}$ The sinterbility modulus of rupture Vickers hardness evaporation of components phase form-tion and mcicrostructure were evaluated with antimonia content. Also two probe A. C conductivity measurement was subjected to all specimens and the best results are achieved with 1mol% $Sb_2O_3$ as a sinter agent and relative density of~98% obtained at 140$0^{\circ}C$ and this composition has a maximum electrical conductivity due to the possible substition of $Sb^{3+}$ for $Zr^{4+}$ site. The effect of $Sb_2O_3$ on the electrical conductivity of th bulk and the grain boundaries has on investigated using frequency dispersion analysis (5~106 Hz) Antimonia addition has a negative in-fluence on both the bulk and the grain boundary conductivity except for a 1 mon% addition. The additive antimonia has improve a modulus of rupture to 60~MPa due to metastable-tetragonal phase apparence and decrease the hardness with increasing the $Sb_2O_3$ content.

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VALUE OF BARLEY GRAIN AND COTTONSEED CAKE AS SUPPLEMENTS TO FOURWING SALTBUSH, AND THE LIVE WEIGHT GAINS AND WATER CONSUMPTION OF SHEEP FED THE DIETS

  • Rehman, Atiq-ur;Thompson, E.F.;Rafique, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.6
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    • pp.647-650
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    • 1996
  • Fifteen sheep were used in a trial which compared the feeding value of whole barley gain and cottonseed cake as supplements to a basal diet of leaves of fourwing saltbush (Atriplex canescens). Diet SB contained 700 g (air-dry matter) of saltbush alone, diet SB + BG contained 700 g SB with 400 g whole barley grain and diet SB + CS contained 700 g SB with 400 g cottonseed cake. The digestibility of the dry matter of diets SB (69%) and SB + CS (70%) were lower (p < 0.001) than of diet SB + BG (76%). Sheep offered SB alone daily lost 80g whereas those fed the other diets gained 11 g (SB + CS) or 17 g (SB + BG) per day. Daily water consumption of the sheep offered the three diets was similar (p > 0.05), but their water consumption was higher (p < 0.001) than that of sheep offered daily 700 g wheat straw and 200 g barley grain. The results indicate that, at the levels of feeding used, barley grain and cottonseed cake had similar value as supplements to fourwing saltbush harvested in summer. The addition of the supplement allowed the sheep to gain some live weight. However, the presence of saltbush leaves in the diet resulted in higher water intakes by the sheep.

Co-adsorption of Irreversibly Adsorbing Sb and Te on Pt(111)

  • Ku, Bon-Seong;Kim, Tae-Gon;Jung, Chang-Hoon;Zhao, Jisheng;Rhee, Choong-Kyun
    • Bulletin of the Korean Chemical Society
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    • v.26 no.5
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    • pp.735-739
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    • 2005
  • Presented is a voltammetric study of co-adsorption of irreversibly adsorbing Sb and Te on Pt(111). When a layer of Sb and Te was formed via simultaneous adsorption, the reduction peak of Te was observed at 0.30 V in the initial cathodic scan. In contrast, sequential adsorption of Sb followed by Te adsorption led to a Te reduction peak at 0.50 V in the initial scan. As the voltammetric scan was continued, in addition, the voltammogram of the simultaneously co-adsorbed layer changed, while that of the sequentially co-adsorbed layer did not. These observations are discussed in terms of formation of a homogeneously mixed layer and a layer consisting of heterogeneously separated domains of Sb and Te. Also, the difference in the adsorption strength of Sb and Te was observed.

Microstructural features of Laser Radiated GeSbTe Intermetallic Compounds (레이저 조사시킨 GeSbTe 금속간 화합물의 미세조직)

  • 박정우;김명룡
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.05a
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    • pp.66-72
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    • 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.

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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
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.3
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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.

Piezoelectric and Dielectric Properties of (Na,K)(Nb,Sb)$O_3$ Ceramics According to the Amount of $Bi_2O_3$ Addition ($Bi_2O_3$ 첨가에 따른 (Na,K)(Nb,Sb)$O_3$ 세라믹스의 압전 및 유전 특성)

  • Lee, Sang-Ho;Yoo, Ju-Hyun;Jeong, Yeong-Ho;Park, Yong-Wook
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.305-305
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    • 2010
  • In this study, in order to develop excellent lead free piezoelectric ceramics for piezoelectric transformer application (Na,K)(Nb,Sb)$O_3$ ceramics were fabricated using conventional oxides mixed method and their piezoelectric and dielectric characteristics were investigated according to the amount of $Bi_2O_3$ addition.

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Dielectric Properties of Barium Titanate with $Sb_2O_3$ and ZnO ($Sb_2O_3$와 ZnO를 첨가한 Barium Titanate의 유전성)

  • 윤기현;김종우;송효일
    • Journal of the Korean Ceramic Society
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    • v.21 no.2
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    • pp.121-126
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    • 1984
  • The dielectric properties of $BaTiO_3$ containing 0~0.3mol% and ZnO respectively as additives were investigated as a function of temperature from $25^{\circ}C$ to 14$0^{\circ}C$ and frequency from 24 KHz to 15MHz. The density of sintered $BaTiO_3$ was increased with addition of increasing to 0.15mol% amounts of $Sb_2O_3$ and the dielectric constant was also increased. This is due to space charge polarization with Ba vacancies. Above 0.15mol% $Sb_2O_3$ the density was decreased and the dielectric constant was also decreased due to occuring the discharge through voids. The density of sintered $BaTiO_3$ was decreased with addition of increasing to 0.15mol% amounts of ZnO and the dielectric constant was decreased due to occuring the discharge through voids. Above 0.15mol% ZnO the density was increased and the dielectric constant was also increased.

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Catalytic Oxidation of Carbon Monoxide on Pt and $SnO_2$ (Pt 및 $SnO_2$ 촉매하에서의 일산화탄소의 산화반응)

  • Kwang Yul Choo;Hasuck Kim;Bonghyun Boo
    • Journal of the Korean Chemical Society
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    • v.24 no.3
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    • pp.183-192
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    • 1980
  • Oxidation reactions of carbon monoxide on $SnO_2$, Sb-doped $SnO_2$, and Pt catalyst were studied. The oxidation reaction was found to be first order with respect to both CO and O$_2$ on $SnO_2$ and Sb-doped $SnO_2$ catalysts, and to be of half order on Pt catalyst. A small addition of Sb to $SnO_2$ (depant composition: 0.05∼0.1 mol %) increased the rate of oxidation. On the contrary, a large addition decreased the rate. From the rate expression of oxidation on Pt catalyst, the inhibition effect of carbon monoxide on the rate of oxidation was deduced. The experimentally obtained activatio energies were 5.7 kcal for the Sb doped $SnO_2$ catalyst (dopant composion: 0.05 mole%), and 6.4 kcal for the Pt catalyst. A possible reaction mechanism was proposed from the experimentally obtained kinetic data.

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The Microstructure and Electrical Properties in the Pb(Sb1/2 Nb1/2)O3-PbTiO3-PbZrO3 System with MnO2 Addition (Pb[(Sb1/2 Nb1/2)0.08 Zr0.49 Ti0.48]O3에서의 MnO2 첨가에 따른 미세구조와 전기적 물성변화에 대한 연구)

  • 강원호;박원규;김호기
    • Journal of the Korean Ceramic Society
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    • v.24 no.6
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    • pp.537-542
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    • 1987
  • The microstructure and electrical properties of Pb[(Sb1/2 Nb1/2)0.08 Zr0.49 Ti0.48]O3 with MnO2 addition have been investigated in this work. The amount of MnO2 addition was 0, 0.4, 0.8, 1.2, 2.0 wt%, respectively. The soild solution range of MnO2 that assumed in this composition according to thevariations of micro-structure and electrical properties was 0.4-0.8 wt%.

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