• Korean Chemical Engineering Research
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• v.43 no.3
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• pp.352-359
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• 2005

This work has studied the changes of pH in both of anodic and cathodic chambers of a divided cell due to the electrolytic split of water during the ammonia decomposition to nitrogen, and has studied the continuous decomposition characteristics of ammonia in a multi-cell stacked electrolyzer. The electrolytic decomposition of ammonia was much affected by the change of pH of ammonia solution which was caused by the water split reactions. The water split reaction occurred at pH of less than 8 in the anodic chamber with producing proton ions, and occurred at pH of more than 11 in the cathodic chamber with producing hydroxyl ions. The pH of the anodic chamber using an anion exchange membrane was sustained to be higher than that using a cation exchange membrane, which resulted in the higher decomposition of ammonia in the anodic chamber. By using the electrolytic characteristics of the divided cell, a continuous electrolyzer with a self-pH adjustment function was newly devised, where a portion of the ammonia solution from a pHadjustment tank was circulated through the cathodic chambers of the electrolyzer. It enhanced the pH of the ammonia solution fed from the pH-adjustment tank into the anodic chambers of the electrolyzer, which caused a higher decomposition yield of ammonia. And then, based on the electrolyzer, a salt-free ammonia decomposition process was suggested. In that process, ammonia solution could be continuously decomposed into the environmentally-harmless nitrogen gas up to 83％, when chloride ion was added into the ammonia solution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1227-1232
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• 2016

Electrolyzed activated water (EAW) has been reported to exhibit strong bactericidal effects on foodborne microorganisms. However, the disinfection efficacy of EAW is affected by factors such as water source and hardness. This study investigated bactericidal effects of EAW against three gram-positive (Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus) and three gram-negative (Cronobacter sakazakii, Escherichia coli O157:H7, and Salmonella Enteritidis) foodborne pathogens. Six strains were treated with EAW prepared at different water temperatures (4, 22, and $40^{\circ}C$) for 15 min, and D-values were generated. The results show that the lowest D-values for Lis. monocytogenes by EAW produced at $4^{\circ}C$ and $40^{\circ}C$ were 6.60 and 1.57 min, respectively. The lowest D-value for Sal. Enteritidis by EAW produced at $22^{\circ}C$ was 2.92 min. D-values of all strains treated by EAW produced at $40^{\circ}C$ decreased significantly compared to those treated by EAW produced at $4^{\circ}C$ (P<0.05). These results demonstrate that applying EAW produced at warm temperature is more effective for reducing foodborne pathogens for food safety.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.236-236
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• 2004

삼중수소수 오염처리의 선행공정으로 적합한 전기분해-촉매교환 결합공정(CECE process)은 수소동위원소 산화물의 수소화 전환을 위한 전해셀과 다단 액상촉매 교환탑으로 이루어진 탈삼중수소 공정이다(그림 1). 촉매탑은 수소 흐름에 수증기를 동반하도록 하는 친수층과 수증기-수소간의 수소동위원소 교환반응을 유도하는 촉매층으로 구분되며, 탑 상부에는 수소의 산화 반응기 그리고 하부에는 물의 수소화 전해셀로 구성되어 있다(그림 2).(중략)

• Membrane Journal
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• v.19 no.1
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• pp.1-6
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• 2009

Hydrogen energy id the 2nd clean energy able to be produced from the abundant resources, and the products of combustion or reaction do not spread an environmental pollution. Also, the hydrogen is the chemical media easily to transport and storage as energy source. The hydrogen production technology using by water splitting through electrolysis could be usable as a permanent renewable energy system without the environmental impact. The key technology of high temperature steam electrolysis is the development of an electrolyte rapidly to conduct an oxygen or proton ion decomposed from water. Subsequently, the important technology is to keep the joining technology of an electrolyte membrane and electrode materials to affect into the current efficiency.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.101-109
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• 2005

In order to produce only a pH-controlled solution without discharging any unused solution, this work has developed a continuous electrolytic system with a pH-adjustment reservoir being placed before an ion exchange membrane-equipped electrolyzer, where as a target solution was fed into the pH-adjustment reservoir, some portion of the solution in the pH-adjustment reservoir was circulated through the cathodic or anodic chamber of the electrolyzer depending on the type of the ion exchange membrane used, and some other portion of the solution in the pH-adjustment reservoir was discharged from the electrolytic system through other counter chamber with its pH being controlled as acid or base. The phenomena of the pH being controlled in the system could be explained by the electro-migration of the ion species in the solution through the ion exchange membrane under a cell potential difference between anode and cathode and its consequently-occurring non-charge equilibriums and electrolytic water- split reactions in the anodic and cathodic chambers.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.245-245
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• 2004

현재 한국원자력 연구소에서 개발되고 있는 사용후 핵연료의 차세대관리기술은 산화물 핵연료를 전해환원시켜 금속으로 관리하는 기술이다. 이 공정에서 발생된 LiCl 폐용융염은 Cs, Sr과 같은 핵분열 생성물을 함유하고 있으며, 그 자체로서 수용성이고 방사선에 분해가 잘 되므로 처분 수용기준에 맞게 안정화시켜 처리해야 한다. 현재 이를 처리하기 위한 방법으로 고온에서도 핵분열 생성물의 이온교환 및 흡착이 가능한 제올라이트 A를 이용한 이온교환 및 단순혼합 방식이 주로 적용되고 있다.(중략)

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.144-144
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• 2017

제한된 조건에서 타이타늄을 양극산화 하였을 때, 자기 정렬된 나노 튜브 형태의 티타니아 구조를 얻을 수 있으며, 그 형태는 양극산화 조건에 따라 변할 수 있음은 학계에 이미 잘 알려져 있다. 그러나 자세한 메커니즘과 전기화학적 조건들은 아직 명확하게 밝혀지지 않았다. 본 연구에서는 자기 정렬된 티타니아 나노 구조의 형태학적 변화를 인가전압과 혼합 전해질의 농도를 변화시켜가며 체계적으로 연구하여, 티타니아 나노 튜브와 마이크로 콘이 생성되는 조건에 대한 지도를 그렸다. 일반적으로 인가 전압이 증가하고, 혼합 전해질에서의 불산의 농도가 낮을수록, 티타니아 나노 구조가 나노튜브에서 마이크로 콘으로 변화하는 것을 확인하였다. 티타니아의 다양한 기능적인 특성을 바탕으로, 구조변화에 대한 전기화학적 이해를 통해, 물 분해, 연료 감응형 태양전지(DSSCs), 광촉매, 가스 센서 등에 적용될 수 있을 것으로 기대한다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.4
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• pp.269-278
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• 2005

In order to produce only a pH-controlled solution without discharging any unwanted solution, this work has developed a continuous electrolytic system with a pH-adjustment reservoir being placed before an ion exchange membrane-equipped electrolyzer, where as a target solution was fed into the pH-adjustment reservoir, some portion of the solution in the pH-adjustment reservoir was circulated through the cathodic or anodic chamber of the electrolyzer depending on the type of the ion exchange membrane used, and some other portion of the solution in the pH-adjustment reservoir was discharged from the electrolytic system through the other counter chamber with its pH being controlled. The internal circulation of the pH-adjustment reservoir solution through the anodic chamber in the case of using a cation exchange membrane and that through the cathodic chamber in the case of using an anion exchange membrane could make the solution discharged from the other counter chamber effectively acidic and basic, respectively. The phenomena of the pH being controlled in the system could be explained by the electro-migration of the ion species in the solution through the ion exchange membrane under a cell potential difference between anode and cathode and its consequently-occurring non-charge equilibriums and electrolytic water- split reactions in the anodic and cathodic chambers.

• Journal of the Korean Chemical Society
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• v.37 no.10
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• pp.888-894
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• 1993

The electrochemical behaviors of copper-1-(2-pyridylazo)-2-naphthol(Cu-PAN) complex in acetonitrile (AN) solution have been investigated by the use of cyclic voltammetry, DC-polarography, controlled potential coulometry and UV-Vis spectroscopy. Cu-PAN complex in acetonitrile exhibit three reduction waves at -1.27 V, -1.64 V and -2.08 V vs. Ag/AgNO$_3$(AN). The numbers of electron involved in each reduction step was calculated with controlled potential coulometry, and reduction product was identified with UV-Vis spectrum. As the result, we proposed the reduction mechanism of the Cu-PAN complex in acetonitrile.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.347-347
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• 2003

폴리아크릴로니트릴을 NaOH로 가수분해시키면 carboxylate anion과 carboxanlide기가 생성되며, 물을 흡수할 경우 sodium carboxylate기의 해리로 팽윤이 크게 일어나므로 고흡수성을 지니게 된다. 일찍이 flory[1]는 가교된 고분자 전해질이 고흡수성을 나타내는 겔을 형성할 것으로 예측한 바 있다. 이 가교 결합이 아크릴 섬유의 부분 가수분해에 대한 자료는 새로운 기능을 부여하면서 섬유의 물성을 어느 정도 유지하는데 요구되는 조건을 제시하게되므로 향후 아크릴 섬유의 개질에 활용될 수 있다. (중략)