• 제목/요약/키워드: anode

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효소연료전지의 Anode 제조조건이 OCV에 미치는 영향 (Effect of Fabrication Method of Anode on OCV in Enzyme Fuel Cells)

  • 김영숙;이세훈;추천호;나일채;이호;박권필
    • Korean Chemical Engineering Research
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    • 제53권1호
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    • pp.6-10
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    • 2015
  • 효소 전극 anode와 PEMFC용 전극 cathode를 이용하여 효소연료전지를 구동하였다. 효소 anode는 그래파이트 분말과 효소로서 글루코스 산화제, 전자매개체로서 페로센을 혼합해 압축해서 만들고 Nafion 이오노머로 코팅하였다. anode 제조조건을 변화시키며 OCV를 측정해 효소 anode 제조 최적조건을 찾았다. 효소 anode 압축 시 최적 압력은 9.0 MPa였다. 효소 anode에서 그래파이트가 60%일 때 최고의 OCV를 나타냈다. anode 기질 용액의 최적 글루코스 농도는 1.7 mol/l이었으며, anode의 효소 활성은 7일 동안 안정적으로 유지되었다.

Compact Anode Design with the Heat Capacity Performance in Rotating Anode X-ray Tube for Digital Radiography

  • Lee, Seok Moon
    • Applied Science and Convergence Technology
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    • 제24권5호
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    • pp.136-141
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    • 2015
  • We studied the compact anode design to develop 100 kW rotating anode X-ray tube with large focal spot 1.2 mm, small focal spot 0.6 mm and tube voltage 150 kV for large hospital digital radiography using computer thermal simulation. The larger thermal radiation effect in a high vacuum can reduce the temperature of anode so the method to increase the surface area of anode is investigated. The anode has the multi-tier shape at the back side of TZM body of anode and also bigger diameter of anode. The number of multi-tiers was varied from 6 to 15 and the diameter of anode was also varied from ${\Phi}74$ to ${\Phi}82$. From ANSYS transient thermal simulation result, we could obtain $1056.4^{\circ}C$ anode maximum temperature when applying 100 kW input power at 0.1 second on target focal track which is less than $1091^{\circ}C$ of the conventional 75 kW X-ray tube with reduced anode weight by 15.5% than the conventional anode. The compact anode of reduced anode weight is able to improve the unwanted noise when the rotor is rotating at high-speed and also reduce the rotational torque which the cost effective stator-coil is possible. It is believed that the anode with 15 ea multi-tiers using ${\Phi}82$ can satisfy with the specification of the anode heat capacity. From the results of this paper, it has been confirmed that the proposed compact anode can be used as the anode of 100 kW rotating anode X-ray tube for digital radiography.

Numerical Analysis of Anode Sheath Structure Shift in an Anode-layer Type Hall Thruster

  • Yokota, Shigeru;Komurasaki, Kimiya;Arakawa, Yoshihiro
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년 영문 학술대회
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    • pp.602-605
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    • 2008
  • The anode sheath structure in the hollow anode of an anode-layer type Hall thruster was numerically computed using a fully kinetic 2D3V Particle-in-Cell and Direct Simulation Monte Carlo(PIC-DSMC) code. By treating both ions and electrons as particles, anode surface region, which is electrically non-neutral, was analyzed. In order to analyze in detail, the calculation code was parallelized using Message Passing Interface (MPI). The code successfully simulated the discharge current oscillation. In the low magnetic induction case, ion sheath appears in the anode surface because ionization is enough to maintain the plasma occurs in the anode hollow. As the magnetic induction increases, main ionization region move to outside of the anode. At the same time, anode sheath voltage decreases. In the high magnetic induction case, electron sheath appears on the anode surface periodically because the ionization occurs mainly in the discharge channel. This anode sheath condition shift can be explained using the simple sheath model.

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효소연료전지의 Anode 제조조건이 성능에 미치는 영향 (Effect of Fabrication Method of Anode on Performance in Enzyme Fuel Cells)

  • 이세훈;황병찬;이혜리;김영숙;추천호;나일채;박권필
    • Korean Chemical Engineering Research
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    • 제53권6호
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    • pp.667-671
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    • 2015
  • Anode는 효소를 이용한 효소전극과 cathode는 PEMFC용 전극을 이용해 효소연료전지를 구동하였다. 효소 anode는 graphite 분말과 효소로서 글루코스 산화제, 전자매개체로 ferrocene을 혼합해 압축해서 만들고 Nafion 이오노머로 코팅하였다. Anode 제조조건을 변화시키며 성능을 측정해 효소 anode 제조 최적조건을 찾았다. 효소 anode 압축 시 최적 압력은 8.89 MPa이고, 효소 anode의 graphite 성분비가 60%일 때 최고의 출력밀도를 나타냈다. Anode 기질 용액의 최적 glucose 농도는 1.7mol/l이었다. 효소 anode는 Nafion 용액에 1초, 2회 침지에 의해 안정화되었다.

연료극 지지체식 원통형 고체산화물 연료전지의 제조 및 특성연구 (Fabrication and Characteristics of Anode-Supported Tubular Solid Oxide Fuel Cell)

  • 김응용;송락현;신동열;임영언
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 D
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    • pp.1547-1549
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    • 1999
  • As a preliminary experiment for the development of anode-supported tubular cell with proper porosity, we have investigated the anode substrate and the electrolyte-coated anode tube. The anode substrate was manufactured as a function of carbon content in the range of 20 to 50 vol.%. As the caron content increased, the porosity of the anode substrate increased slightly and the carbon content with proper porosity was obtained at 30 vol.%. The anode tube was fabricated by extrusion process and the electrolyte layer was coated on the anode tube by slurry dipping process. The anode-supported tube was cofired successfully. Their sintered property and microstructure were examined and the porosity of the anode tube was 35%. From the gas permeation test, the anode tube was found to be porous enough for gas supply. On the other hand, the anode-supported tube with electrolyte layer indicated a very low gas permeation rate. This means that the coated electrolyte was dense. Based upon these experimental results. we will fabricate and test the anode-supported tubular cell.

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해양환경 변화가 알루미늄합금 희생양극의 효율에 미치는 영향에 관한 연구 (A Study on the Influence of Al Alloy Sacrificial Anode Efficiency due to Marine Environmental Variation)

  • 김도형
    • 한국해양공학회지
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    • 제14권2호
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    • pp.106-111
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    • 2000
  • Recently it was reported that the life of Al Sacrifical anode is being used in port piers has been significantly shortened compared with the original design life (e.g. average life shortened from 20 years to 13-15 year) Those factors involving these problems mentioned above were seemed to be a quality of anode material and diverse environmental factors such as pH flow rate temperature Dissolved oxygen Chemical oxygen demand and resistivity etcm In this study flow rate and contamination degree(pH) of sea water affecting to sacrificial anode life hve been investigated in terms of electrochemical characteristics of Al alloy sacrificial anode It was known that the lifetime of Al alloy anode was shortened not only by increasing of self-corrosion quantity by varying flow rate of sea water but also by increasing corrosion current density due to the potential difference increment between Al anode and steel structure cathode by varying contamination degree of sea water. Especially when anode current density is from 1mA/cm2 to 3mA/cm2 and flow rate of sea water is under 2m/s anode current efficiency is 90% above However flow rate is over 2m/s anode current efficiency fell down sharply due to erosion corrosion as well as galvanic corrosion.

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IZTO 애노드를 이용하여 제작한 인광 OLED 및 플랙시블 OLED 특성 (Characteristics of phosphorescent OLEDs and flexible OLED fabricated indium-zinc-tin-oxide anode)

  • 최광혁;배정혁;문종민;정진아;김한기;강재욱;김장주
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.399-400
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    • 2007
  • In this work, we have investigated the characteristics of the phosphorescent OLED and flexible OLED fabricated on IZTO/glass and IZTO/PET anode film grown by magnetron sputtering, respectively. Electrical and optical characteristics of amorphous IZTO/glass anode exhibited similar to commercial ITO anode even though it was deposited at room temperature. In addition, the amorphous IZTO anode showed higher work function than that of the commercial ITO anode after ozone treatment for 10 minutes. Furthermore, a phosphorescent OLED fabricated on amorphous IZTO anode film showed improved current-voltage-luminance characteristics, external quantum efficiency and power efficiency in contrast with phosphorescent OLED fabricated on commercial ITO anode film. This indicates that IZTO anode is promising alternative anode materials for anode in OLEDs and flexible OLEDs.

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Impedance and Thermodynamic Analysis of Bioanode, Abiotic Anode, and Riboflavin-Amended Anode in Microbial Fuel Cells

  • Jung, Sok-Hee;Ahn, Young-Ho;Oh, Sang-Eun;Lee, Jun-Ho;Cho, Kyu-Taek;Kim, Young-Jin;Kim, Myeong-Woon;Shim, Joon-Mok;Kang, Moon-Sung
    • Bulletin of the Korean Chemical Society
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    • 제33권10호
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    • pp.3349-3354
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    • 2012
  • Understanding exoelectrogenic reactions of the bioanode is limited due to its complexity and the absence of analytics. Impedance and thermodynamics of bioanode, abiotic anode, and riboflavin-amended anode were evaluated. Activation overpotential of the bioanode was negligible compared with that of the abiotic anode. Impedance spectroscopy shows that the bioanode had much lower charge transfer resistance and higher capacitance than the abiotic anode in low frequency reaction. In high frequency reaction, the impedance parameters, however, were relatively similar between the bioanode and the abiotic anode. At open-circuit impedance spectroscopy, a high frequency arc was not detected in the abiotic anode in Nyquist plot. Addition of riboflavin induced a phase angle shift and created curvature in high-frequency arc of the abiotic anode, and it also drastically changed impedance spectra of the bioanode.

ANODE HEATING AND MELTING IN THE ARGON GTA

  • Terasaki, Hidenori;Tanaka, Manabu;Fujii, Hidetoshi;Ushio, Masao
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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    • pp.746-751
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    • 2002
  • In order to make clear the physical relation among the arc plasma, the anode heat transfer and the weld penetration, the results of experimental measurements of temperatures of arc plasma, the distributions of heat input and current on the anode and the weld penetration were presented The experimental results showed that the electron temperature above the anode and current and heat input density on the anode was dominated by the position of the cathode. Furthermore, it was showed that electron temperature of arc plasma was dominated by the cathode shape. These results were related with the results of the welded penetration measurements. As a result, it was showed that the electron temperature above the anode and current density distribution on the anode decided the heat input density distribution on the anode and that the heat input density on the anode remarkably dominated the size of the weld penetration in argon GTA welding process. Furthermore, it was suggested that the cathode played the important role in the determination of the weld penetration in argon GTA welding process.

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Characteristics of Sr0.92Y0.08TiO3-δ Anode in Humidified MethaneFuel for Intermediate Temperature Solid Oxide Fuel Cells

  • Park, Eun Kyung;Yun, Jeong Woo
    • Journal of Electrochemical Science and Technology
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    • 제7권1호
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    • pp.33-40
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    • 2016
  • Sr0.92Y0.08TiO3-δ (SYT) was investigated as an alternative anode in humidified CH4 fuel for SOFCs at low temperatures (650 ℃-750 ℃) and compared with the conventional Ni/yttria-stabilized zirconia (Ni/YSZ) anode. The goal of the study was to directly use a hydrocarbon fuel in a SOFC without a reforming process. The cell performance of the SYT anode was relatively low compared with that of the Ni/YSZ anode because of the poor electrochemical catalytic activity of SYT. In the presence of CH4 fuel, however, the cell performance with the SYT anode decreased by 20%, in contrast to the 58% decrease in the case of the Ni/YSZ anode. The severe degradation of cell performance observed with the Ni/YSZ anode was caused by carbon deposition that resulted from methane thermal cracking. Carbon was much less detected in the SYT anode due to the catalytic oxidation. Otherwise, a significant amount of bulk carbon was detected in the Ni/YSZ anode.