• 환경위생공학
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• 제19권3호
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• pp.31-39
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• 2004

In order to reduce the pollution load from the livestock farms and to improve the water quality of the effluent in livestock wastewater, the electrolysis system is introduced. For the selection of optimal electrode, various combination of electrodes such as carbon, Al and Fe were examined. In this study, electrode material, electrolyte concentration, electrode distance, current density, and pH value were found to have significant effect on both pollutant removal efficiency and current efficiency in electrochemical oxidation process. After electrolysis for 90 min with carbon/Al, it was observed that COD, T-N, T-P and $NH_4^+-N$ of livestock waste-water were removed with $80\%,\;61\%,\;81\%\;and\;87\%$, respectively.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1277-1281
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• 2007

A Nano-tip as a cold field emitter for inducing a field emission current has manufactured in many ways. In the paper, the electrochemical etching method is used. Thus, in order to optimize the final shape as the field emitter, the reliable fabrication system for electrochemical etching was constructed. In addition, the effective parameters such as applied voltage, submerged length, meniscus height, electrolyte concentration and environmental condition(vibration, humidity, cut-off time) have investigated in detail. By controlling the parameters, reliable tungsten tip for field emitter was fabricated. And the fabricated tungsten tip was evaluated optically. Finally, the very sharp apex of the tungsten tip was observed with scanning electron microscope.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 춘계학술대회 논문집
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• pp.217-220
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• 2001

In the shearing process the burr or rollover must be minimized in order to improve the quality of product. The burr size can be minimized by control of several process parameters. But removal of all burrs are impossible. Most mechanical type deburring methods (vibrating bowls, rotating barrels, shot blasting, for example.) will remove large burrs, other methods use chemical (electro-chemical deburring) or heat (thermal energy deburring). The electro-chemical deburring process removes burrs by the deplating method. Electro-chemical deburring equipment is requires a small capital investment than other methods(mechanical or thermal methods). Electro-chemical deburring method need to many parameters for control such as a time, voltage and concentration of electrolyte. In this paper shows relations of these parameters by experiment.

• 에너지공학
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• 제2권3호
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• pp.300-307
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• 1993

고성능 니켈-철 축전지를 개발하기 위하여 철전극에 대한 충방전 반응 특성을 전위주사법, SEM, XRD분석으로 조사하였으며, 또한 전극용량을 정전류 충방전 시험법으로 조사하였다. 전해질 온도 및 농도가 전극용량에 크게 영향을 미쳤으며, 특히 온도가 상승함에 따라 1차 방전용량이 증가하였다. 증공제는 전극용량에 거의 영향을 미치지 못하였다. 전극용량은 방전율 0.25C에서 350㎃h/g (이용율 36%) 이상으로 나타났고, 전극의 안정성도 양호하게 나타났으나 활성화가 느리게 일어났다.

• 한국안전학회지
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• 제13권2호
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• pp.96-103
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• 1998

The treatment of the wastewater of Carmine-6B Process was studied using an electrochemical batch reactor with Pt-electrodes. The concentration of azo dye was exponentially decreased unto 6-37% residuum during 50 hr operations. The fractional conversion was not influenced by the initial pH value, but it was increased with increasing the rotating speed and/or temperature of the electrolyte. It was observed by the differential method of rate analysis that the rate of the oxidation reaction at anode was exponentially increased with increasing the cell voltage. The pH of the wastewater was changed from acid or alkali to neutral. The COD of the solution was increased at the beginning of the treatment, but it was decreased soon.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.273-273
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• 2006

The encapsulation of volatile organic electrolytes is a major challenge in practical applications of the DSSC. Ionic liquid (IL) within polymer electrolytes is an attractive candidate for replacement. Here we used a low viscosity ionic liquid 1-ethyl 3-methylimidazolium thiocyanate in order to modify ionic conductivity (${\sigma}$) of polymer electrolyte ($PEO:Kl/l_{2}$) and hence DSSC efficiency. The doping of IL enhanced ${\sigma}$ and attained maximum (${\sigma}=7.62{\times}10^{-4}S/cm$) at 80 wt% of IL concentration. Beyond this it was harder to get stable films. XRD confirmed that the intensity of the sharp PEO crystalline peaks decreased when IL was added. The DSC studies confirmed the reduction in crystallinity by adding ionic liquid.The efficiency of solar cell using aforesaid material was 0.6 % at 1 sun irradiation.

• 한국수소및신에너지학회논문집
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• 제18권4호
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• pp.446-451
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• 2007

Physicochemical properties of carbon nanofibers were evaluated as a supercacitor electrode materials could store electrochemical energy reversibly. A capacitance of carbon nanofiber electrode was increased gradually, depending on the PVDF binder ratio. A feasibility of EDLC electrode was estimated with specific surface area measurement by BET method and mesopore structure of carbon nanofiber surface could be explained electrochemical absorption-desorption in aqueous electrolyte. PVDF 5 wt.% ratio in electrode was observed a suitable binder amount by CV result.

• E2M - 전기 전자와 첨단 소재
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• 제8권3호
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• pp.254-260
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• 1995

A method is described for the design and fabrication of the sensor interface circuits on the Clark electrodes for the dissolved oxygen(DO). The discussion includes a method for the +5 V single-supply driving for the sensor circuits, which has low power comsumption for the front-end electronics. DO probe under test is composed of the Clark electrode with silver anode, gold cathode and the electrolyte of half saturated KCI solution and the FEP teflon memtrance for the oxygen penetration. Typical polarograms for the DO probes by using this sensor circuit reveals high accuracy over 99% of the I to V conversion. Partial pressure of oxygen obtained from the polarograms are well suited to the results calculated. It is expected that the proposed sensor circuits can be utilized into the customized IC for the battery-driven small-size DO meters.

• 한국세라믹학회지
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• 제11권2호
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• pp.11-16
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• 1974

Korean Yung-il bentonite was treated with potassium chloride, zinc chloride, calcium chloride, ferric chloride, or chromic chloride solutions respectively varying their concentration, treating temperature and treating time. The adsorbabilities of methylene blue on these pretreated bentonite were investigated. In the case of treatment with potassium chloride solution, the improvement of the adsorbahility of methylene blue on the products was observed, and in the best result the adsorbability was 1.6 times better than that on the original bentonite. With zinc chloride solution, the optimum adsorbability was a value of 1.7 times better than that on the original bentonite. With ferric chloride, chromic chloride or calcium chloride solution, slight improvement of the adsorbability was observed.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.379-382
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• 2006

We are investigating the effect of particle on electrowetting, and this paper reports the experimental results obtained until now. The experiment was performed for different particle sizes, electrolyte concentration, and AC frequencies. The problem is quite complicated by various factors, such as the existence of surfactant in suspension and sedimentation of particles. We could not draw a concrete conclusion on the effect of particles, and it needs further investigations. We also report interesting phenomena observed during the experiment. It includes the droplet generation at the edge of a droplet, pseudo-bistability of electrowetting, flow generation inside a droplet, and the chain formation of particles inside a droplet.