• 응용화학
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• 제15권2호
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• pp.137-140
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• 2011

Excellent active and stable platinum catalyst fuel cells currently being used as a catalyst. However, because of the high price of platinum catalyst, such as non-precious catalyst has been studied by a variety of fuel cell catalysts. In this study, Co/ PANi//CNT composite catalyst after synthesis through various heating process was to increase the activity of the catalyst. At 700℃ showed the best catalytic activity, using a composite catalyst was to be used as cathode electrodes in fuel cell.

• 한국기계가공학회지
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• 제7권4호
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• pp.24-30
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• 2008

The laminate IPMC actuator have been developed with a commercial Nafion film and platinum electrodes. Equivalent beam and equivalent bimorph beam models for IPMC(Ionic Polymer-Metal Composite) actuators are described. By using a beam equation with estimated physical properities and actuation displacements of a cantilevered IPMC actuator are estimated. And Finite element analysis(FEA) was done by ANSYS.

• 분석과학
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• 제8권4호
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• pp.569-574
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• 1995

In-situ spectroelectrochemical studies have been carried out on the oxidation of Mn(II) at platinum, gold, lead dioxide, and bismuth doped lead dioxide electrodes. The Mn(III), $MnO_2$, and/or ${MnO_4}^-$ species are produced depending on experimental conditions employed during electrolysis. Mn(III) is shown to be produced from a very early stage during the anodic potential scan and undergo disproportionation-conproportionation reactions depending on the relative concentration of each species near the electrode surface. An oxidation mechanism consistent with these observations is proposed.

• Bulletin of the Korean Chemical Society
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• 제15권9호
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• pp.739-743
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• 1994

A spectroelectrochemical system assembled with a white light source, bifurcated optical fiber, Oriel Multispec spectrograph, and a charge-coupled device (CCD) detector is described. The system is shown to be capable of acquiring a whole spectrum in the spectral range of 290-800 nm in 25 ms or a longer period during electrochemical experiments at reflective working electrodes such as platinum or mercury. The utility of the system in studying electrochemical reactions during the potential scan, galvanostatic electrolysis, or after the potential step is demonstrated.

• 대한후두음성언어의학회지
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• 제14권2호
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• pp.83-87
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• 2003

Background and Objectives : Sphincteric function of the larynx, essential to lower airway protection, is most efficiently achieved through strong reflex adduction by both vocal cords. We hypothesize that central facilitation is an essential component of a bilateral adductor reflex and that its disturbance could result in weakened sphincteric closure. Materials and Method : Seven adult 20kg dogs underwent evoked response laryngeal electromyoraphy under 0.5 to 1.0 MAC isoflurane anesthesia. The internal branch of superior laryngeal nerve was stimulated through bipolar platinum-iridium electrodes and recording electrodes were positioned in the ipsilateral and contralateral thyroaryteonoid muscles. Results : Consistent threshold responses were obtained ipsilaterally under all anesthetic levels. However, contralateral reflex responses disappeared as anesthetic levels approached 1.0 MAC. Additionally, at 0.5 MAC, late responses (R2) were detected in one animal. Conclusion : Alteration of central facilitation by deepening anesthesia abolishes the crossed adductor reflex, predisposing to a weakened glottic closure response. Precise understanding of this effect may improve the prevention of aspiration in patients emerging from prolonged sedation or under heavy psychotropic control.

• 한국표면공학회지
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• 제22권2호
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• pp.55-61
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• 1989

A fuel cell which causes electrochemical ratio of conventional with oxygen consists of mainly there parts, such as electrolyte, fuel and oxidant electrode. IN this paper, most efforts were delivered to manufacturing PETE-bonded gas-diffusion electrode, and preparation methods of the porous electrodes has been discussd. A medio temperature, phosphoric acid fuel cell (PAFC) provided with fuel (hydrogen) and oxygen showed oxygen showed excellent performance characteristics with made electrodes. Performance data obtained from hydrgen-oxygen cell were presented to illustrate their properties. It was found that the optimum amounts of platinum in clectrode for hydrgen-oxygen PAFC were about 3mg/cm3 and the PTFE content of gas diffusion layer and catalyst layer were 25% and 15%, respectively.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.119-123
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• 2006

The ionic-polymer-metal-composite actuators have the best merit for bio-mimetic locomotion because of their large bending performance. Especially, they have the advantage for mimicking a fish-like motion because IPMCs are useful to be actuated in water. So we have developed IPMC actuators with multiple electrodes for realization of biomimetic motion. Generally, the IPMC actuator has been fabricated in electroless plating technique, while it needs very long fabrication time and shows poor repeatability in the actuation performance owing to the variables in chemical fabrication process. Therefore, the novel fabrication methods were investigated by combining electroless plating and electroplating techniques capable of patterning precisely. On the whole, two different methods were compared and analyzed with similar thickness level of Platinum electrodes. Present results show that mixing chemical reduction and electroplating can be a promising candidate for electrode patterning.

• 한국재료학회지
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• 제9권4호
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• pp.368-372
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• 1999

The suggested electrode structure of MOCVD-Pt/sputtered-Ru/polysilicon has an excellent adhesion with increasing annealing temperatures and shows a stable electrode structure up to $600^{\circ}C$. However, the ruthenium used for barrier layer increased the roughness of platinum bottom electrodes because ruthenium diffused through the Pt bottom electrode and reacted with oxygen during the annealing above $700^{\circ}C$. The surface roughness increased the resistivity of Pt bottom electrodes. The resistivity of samples annealed at $600^{\circ}C$ was about $13\mu$Ω.cm. The electrode structure was possible to apply for ferroelectric thin film integration of semiconductor memory devices.

• 한국진공학회지
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• 제11권2호
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• pp.103-107
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• 2002

Metal/ferroelectric/semiconductor field effect transistors(MFSFET′s) with various gate electrodes, that are aluminum, platinum and poly-Si, using rapid thermal annealed $LiNbO_3$/Si(100) structures were fabricated and the properties of the FET′s have been discussed. The drain current of the "on" state of FET with Pt electrode was more than 3 orders of magnitude larger than the "off" state current at the same "read" gate voltage of 1.5 V, which means the memory operation of the MFSFET. A write voltage as low as about $\pm$4 V, which is applicable to low power integrated circuits, was used for polarization reversal. The retention properties of the FET using Al electrode were quite good up to about $10^3$ s and using Pt electrode remained almost the same value of its initial value over 2 days at room temperature.

• Macromolecular Research
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• 제10권4호
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• pp.181-186
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• 2002

The displacement of carbon black to polypyrrole as a catalyst supporter in the fuel electrode of a direct methanol fuel cell was investigated. Polypyrrole was obtained as a black powder by the chemical polymerization of pyrrole with three different oxidants. The synthesized polypyrroles were pasted on carbon paper and transformed to the fuel electrodes with electrochemically deposited platinum. The prepared fuel electrode was assembled and mounted in a unit cell using a membrane and cathodic electrode film. In comparison with the carbon black fuel electrode, the performance of the unit cell was analyzed in relation to the state of the catalyst, the type of oxidant, and the morphology of the polypyrrole powder.