• 대한전기학회논문지
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• 제41권1호
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• pp.42-49
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• 1992

Charge accumulation characteristics in low density polyethylene (LDPE) has been discussed based upon the internal charge distrubution measured by the pulsed electroacoustic technique. When the negative voltage with respect to earth is applied to the upper electrode, the negative charges near the anode and the positive charges near the cathode are accumulated in LDPE. Also, there was an asymmetric behavior of charge accumulation exhibiting that the charge accumulation near the anode keeps increasing whereas that near the cathode increases first and then decreases. Besides, under the present test conditions the internal charge distrubution becomes stabilized eventually. When the positive voltage with respect to earth is applied to the upper electrode, on the other hand, no such asymmetric charge accumulation was found. Therefore, it can be concluded that the heterocharges are accumulated at the surface region of LDPE subjected to high do voltages and that the begavior of charge accumulation depends on the polarity of do voltage and the position of charge accumulation.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.134-134
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• 2010

Fuel cell is a device that directly converts chemical energy in the form of a fuel into electrical energy by way of an electrochemical reaction. In the anode for a high temperature fuel cell, nickel or nickel alloy has been used in consideration of the cost, oxidation catalystic ability of hydrogen which is used as fuel, electron conductivity, and high temperature stability in reducing atmosphere. Most MCFC stacks currently operate at an average temperature of $650^{\circ}C$. There is some gains with decreased temperature in MCFC to diminish the electrolyte loss from evaporation and the material corrosion, which could improve the MCFC life. However, operating temperature has a strong related on a number of electrode reaction rates and ohmic losses. Baker et al. reported the effect of temperature (575 to $650^{\circ}C$). The rates of cell voltage loss were 1.4mV/$^{\circ}C$ for a reduction in temperature from 650 to $600^{\circ}C$, and 2.16mV/$^{\circ}C$ for a decrease from 600 to $575^{\circ}C$. The two major contributors responsible for the change in cell voltage with reducing operation temperature are the ohmic polarization and electrode polarization. It appears that in the temperature range of 550 to $650^{\circ}C$, about 1/3 of the total change in cell voltage with decreasing temperature is due to an increase in ohmic polarization, and the electrode polarization at the anode and cathode. In addition, the oxidation reaction of hydrogen on an ordinary nickel alloy anode in MCFC is generally considered to take place in the three phase zone, but anyway the area contributing to this reaction is limited. Therefore, in order to maintain a high performance of the fuel cell, it is necessary to keep this reaction responsible area as wide as possible, that is, it is needed to keep the porosity and specific surface area of the anode at a high level. In this study effective anodes are prepared for low temperature MCFC capable of enhancing the cell performance by using zirconium hydride at least in part of anode material.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.639-639
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• 2013

In this research we report the significant contribution of the as-spun multi-walled carbon nanotube (MWCNT) on the x-ray images formation using a low tube voltage x-ray source. The MWCNT, which was used for the fabrication of the spun CNT, was grown using a microwave plasma-enhanced chemical vapor deposition machine. Electrical-optics simulation software was utilized to determine the electron field emission trajectory of the triode-structure-as-spun CNT-based x-ray source. It was shown that a significant amount of converging electrons hit the target anode producing a clear x-ray image. These x-ray images where produced at a small amount of anode current of 0.67 mA at a tube voltage of 5 kV with the gate voltage of 0 V. Also, comparisons of the radiographs at various exposure times of the sample where analyzed with and without an x-ray dose filter. Results showed that spatially-resolved images were formed using the as-spun CNT at a low tube voltage with a $54-{\mu}m$ Al x-ray filter. This study can be used for low-voltage medical applications.

• 전기전자학회논문지
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• 제25권1호
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• pp.168-173
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• 2021

본 논문에서는 일반적인 ESD 보호소자인 LVTSCR의 구조적 변경을 통해 향상된 전기적 특성을 달성한 새로운 구조의 ESD 보호소자를 제안한다. 또한 요구되는 전압 Application에 따른 ESD Design Window에 최적화된 설계를 위하여 N-Stack 기술을 적용한다. 기존의 LVTSCR 구조에 추가로 삽입된 N-Well 영역은 Anode와 전기적으로 연결함으로써 추가적인 ESD 방전경로를 제공하고 이는 온-저항 및 온도 특성을 향상시킨다. 또한 짧은 Trigger 경로는 기존의 LVTSCR보다 더 낮은 Trigger Voltage 가지므로 우수한 Snapback 특성을 지닌다. 그리고 제안된 ESD 보호소자의 전기적 특성을 검증하기 위해 Synopsys 사의 T-CAD Simulator을 이용하였다.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 1998년도 제1회 총회 및 추계학술발표회
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• pp.87-87
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• 1998

• 한국세라믹학회지
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• 제51권4호
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• pp.357-361
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• 2014

An Ni-Fe/YSZ core-shell structured anode for uniform microstructure and catalytic activity was synthesized. Flat tubular segmented-in-series solid oxide fuel cell-stacks were prepared by decalcomania method using synthesized anode powder. The Ni-Fe/YSZ core-shell anode exhibited better electrical conductivity than a commercially available Ni-YSZ cermet anode. Also power output increased by 1.3 times with a higher open circuit voltage. These results can be attributed to the uniformly distributed Ni particles in the YSZ framework. The impedance spectra of a Ni-Fe/YSZ core-shell anode showed comparable reduced ohmic resistance similar to those of the commercially available Ni-YSZ cermet anodes.

• 한국전기전자재료학회논문지
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• 제19권11호
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• pp.1037-1043
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• 2006

We report the enhancement of hole injection using ozone-treated Ag nanodots dispersed on indium tin oxide anode in $Ir(ppy)_3-doped$ phosphorescent OLED. Phosphorescent OLED fabricated on Ag nanodots dispersed ITO anode showed a lower turn on voltage and higher luminescence than those of OLEDS prepared commercial ITO anode. Synchrotron x-ray scattering examination results showed that the Ag nanodots dispersed on ITO anode is amorphous structure due to low deposition temperature. It was thought that decrease of the energy barrier height as Ag nanodots changed to $AgO_x$ nanodots by surface treatment using ozone for 10 min led to enhancement of hole injection in phosphorescent OLED. Futhermore, efficient hole injection can be explained by increase of contact region between anode material and organic material through introduction of $Ag_2O$ nanodots.

• 전기화학회지
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• 제16권3호
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• pp.138-144
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• 2013

Electrochemical reductions of $UO_2$ at various anode-to-cathode distances (1.3, 2.3, 3.2, 3.7 and 5.8 cm) were carried out to investigate the effect of the anode-to-cathode distance on the electrochemical reduction rate. The geometry of the electrolysis cell in this study, apart from the anode-to-cathode distance, was identical for all of the electrolysis runs. Porous $UO_2$ pellets were electrolyzed by controlling a constant cell voltage in molten $Li_2O-LiCl$ at $650^{\circ}C$. A steel basket containing the porous $UO_2$ pellets and a platinum plate were used as the cathode and anode, respectively. The metallic products were characterized by means of a thermogravimetric analyzer, an X-ray diffractometer and a scanning electron microscope. The electrolysis runs conducted during this study revealed that a short anode-to-cathode distance is advantageous to achieve a high current density and accelerate the electrochemical reduction process.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.158-161
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• 2003

Removal of phenanthrene by electrokinetic method combined with Fenton-like process was studied in a model system. The scale of reactor was 100cm in length, 100cm in width, and 70cm in height. The distance between electrodes was 70cm. Indonesia kaoline was selected as a model soil. When constant voltage of 100 V was applied to this system, current decreased from 200 mA to 100 mA for 14 days. Total accumulated EOF was about 55,000 mL. The concentration of phenanthrene near anode was very low because direction of electroosmosis was from anode to cathode and hydrogen peroxide was supplied to anode reservoir. Phenanthrene concentration was increased as the location was far from anode because hydrogen peroxide was gradually decomposed and then the rate of hydroxyl radical production was decreased.

• 전자공학회논문지D
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• 제34D권6호
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• pp.33-42
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• 1997

In this paper, a new structure for a dC plasma display pane(PDP) with a wall-catode and a wall-auxilizry anode has been suggested. The wall-cathode with a sufficient discharge area maximizes the discharge volume. The auxiliary anode surrounding the discharge region makes the effective control of the charged particles possible. We have investigated the cahracteristics of the new cell structure with a 2-dimensional computer simulation and a micro gap discharge system, and compared experimentally with those of previous cell structure. The new cell structure with the wall-cathode and auxiliary wall-anode turned out to have improved luminance, discharge forming time and sustain voltage.