알루미늄-공기 단위전지의 수소발생속도

심은기,도칠훈,문성인,황영기,Shim Eun-Gi,Doh Chil-Hoon,Moon Seong-In,Hwang Young-Gi 한국전기화학회 2001 한국전기화학회지 Vol.4 No.4

KOH 강염기성 전해질을 사용하는 알루미늄-공기 단위전지에서 합금원소. 전해질에 첨가하는 억제제의 종류, 억제제의 농도, 전해질 온도, KOH 농도, 방전전류밀도 등을 변화시키면서 수소발생속도를 측정하였으며, 각 실험 변수들이 미치는 영향에 대해 조사하였다. 전해질 용액에 ZnO를 포화농도로 첨가하면 첨가하지 않은 경우에 비해 수소발생속도를 $50\%$ 정도로 억제시킬 수 있는 반면에, ZnAc(Zinc Acetate)는 반응억제제로서 역할을 하지 못하였다. KOH 농도와 전해질온도가 높을수록 ZnO의 반응속도 억제효과가 상승하였다. 알루미늄의 수소발생속도는 KOH 농도와 전류밀도에 대해 1차선형 증가함수의 경향을 가지며, 온도에 대해 지수형 증가함수로 나타났다. In an aluminum-air unit cell used alkaline solution, Hydrogen evolution rates were investigated far the observation of the effects of alloy element, inhibitor and its concentration in electrolyte, KOH concentration, solution temperature, and current density loaded to cell. Hydrogen evolution rates were reduced up to $50\%$ by saturating the solution with ZnO, while ZnAc(Zinc Acetate) did not work as inhibitor. The inhibition effect of ZnO increased with increasing the KOH concentration and solution temperature. They were linearly increased with the KOH concentration and current density in first order and exponentially increased with the solution temperature.

알칼리 용액에서 알루미늄의 부식속도 측정

심은기,황영기,전혜수,Shim Eun-Gi,Hwang Young-Gi,Chun Hai-Soo 한국전기화학회 1999 한국전기화학회지 Vol.2 No.3

This study investigated the corrosion rate of aluminum in alkaline solution. It was performed to observe the effects of alloy element, alkalinity (KOH concentration), solution temperature, and inhibitor and its concentration in the solution. Among species of aluminum, AA-1050 showed the lowest corrosion rate due to its high purity $(>199\%)$, whereas alloys containing Mg anuor Mn were highly corroded, relatively. The corrosion rate could be reduced over than $50\%$ by saturating the solution with ZnO, while ZnAc did not work as an inhibitor. The inhibition effect of ZnO increased with increasing the alkalinity and solution temperature. It was found that the corrosion rate linearly increased with the concentration of KOH in first order and exponentially decreased with the inverse of the solution temperature. An analysis of the corroded material covered the surface of aluminum was made by SEM and EDS. According to the analytical results by using XRD, it was confirmed that $Al(OH)_3$ was produced from the corrosion of aluminum in KOH solution. 본 연구에서는 알칼리 용액에서 알루미늄의 부식속도를 측정하면서, 합금원소, 알칼리도(KOH농도),용액온도, 그리고 용액에 첨가하는 부식 억제제의 종류와 그 농도 등이 미치는 영향에 대해 조사하였다. 알루미늄 제품에 따라서는 순도 $99\%$ 이상인 AA-1050의 부식속도가 가장 낮은 반면에 Mg나 Mn이 포함된 합금은 상대적으로 높게 측정되었다. KOH 수용액에 ZnO를 포화농도로 첨가하면 부식속도가 $50\%$ 이상 억제되는 효과가 나타났지만. ZnAc는 부식 억제제로서 역할하지 못하였다. 알칼리도와 용액온도가 높을수록 ZnO의 부식 억제효과는 상승하였다 부식속도는 KOH농도에 대해 1차 선형 증가함수 그리고 온도 역수에 대해 지수형 감소함수로 나타났다. SEM과 EDS를 사용하여 부식 표면에 부착된 물질의 성분을 분석하였으며, XRD의 기기분석을 통하여 KOH 용액에서의 알루미늄의 부식 생성물이 $Al(OH)_3$임을 확인하였다.

Electrochemical Performance of Tris(2-Chloroethyl) Phosphate as a Flame-Retarding Additive for Lithium-Ion Batteries

심은기,박인준,남태흠,김정구,김현수,문성인 대한금속·재료학회 2010 METALS AND MATERIALS International Vol.16 No.4

We studied tris(2-chloroethyl) phosphate (TCEP) as a potential flame-retarding additive and its effect on the electrochemical cell performance of lithium-ion battery electrolytes. The electrochemical cell performance of additive-containing electrolytes in combination with a cell comprised of a LiCoO2 cathode and a mesocarbon microbeads anode was tested in coin cells. The cyclic voltammetry results show that the oxidation potential of TCEP-containing electrolyte is about 5.1 V (vs. Li/Li+). A cell with TCEP has a better electrochemical cell performance than a cell without TCEP in an initial charge and discharge test. In a cycling test, a cell containing a TCEP-containing electrolyte has a greater discharge capacity and better capacity retention than a TCEP-free electrolyte after cycling. The results confirm the promising potential of TCEP as a flame-retarding additive and as a means of improving the electrochemical cell performance of lithium-ion batteries.

석회석을 이용한 폐광산폐수처리

심은기,김은호,박인수,황영기 경남대학교 신소재연구소 1999 論文集 Vol.11 No.-

석회석을 이용하여 혐기성 처리를 위한 폐광산폐수의 화학적 전처리 특성을 평가하였다. 반응시간에 따른 석회석에 의한 처리시 반응종료 2시간에 pH 3.67이였고 SO42-4.7%, Fe 26%, Al 22%, Pb 18% 및 Mn 8%의 제거효율로서 소석회에 비하여 낮은 처리특성을 보여주고 있다. 석회석의 반응속도는 온도가 증가함에 따라 감소하는 경향을 보였다. 혐기성 석회석 충진층의 경우에 실험기간내 pH는 평균 4.51이였고 SO42-4.5%, Fe 15.3%, Al 20.1%, Pb 23.7% 및 Mn 5.87%의 평균 제거효율을 나타내었다. 혐기성 석회석 충진층은 pH 상승효과가 그다지 없었으며 SO42- 및 중금속제거율 또한 아주 낮아 석회석만으로 폐광산폐수의 처리에는 한계점이 있는 것으로 평가되었다. 그러나, 폐광산폐수를 SRB에 의한 처리시의 전처리 공정으로 활용한다면 강산성인 폐광산폐수를 초기에 pH를 상승시켜 처리계에 높은 알칼리도를 제공함으로서 시스템의 안정화에 기여할 수 있을 것으로 여겨진다. This research was carried out to investigate chemical pretreatment using limestone in treat in g abandoned mine drainage with anaerobic treatment. If treating limestone with abandoned mine drainage. after 2day. pH was increased to 3.67, and So₄^{2-}, Fe. Al. Pb and Mn were removed 4.7%. 26%. 22%. 18% and 8%. respectively. It could be showed that limestone did slowly react with temperature increasing. If treating anaerobic limestone packing column with abandoned mine drainage. for experimental period. average pH was 4.51, and average So₄^{2-}, Fe. Al, Pb and Mn were removed 4.5%. 15.3%. 20.1%. 23.7% and 5.87%. respectively. So, it would not be suitable for abandoned mine drainage. But if utilizing limestone as pre- treatment process for treating abandoned mine drainage with SRB, becaus it did initally neutralize abandoned mine drainage, it could forward to stabilize system.

아토피 피부염 치험 2례

심은기,안찬근,두인선,황충연,Shim, Eun-Ki,An, Chan-Gn,Du, In-Sun,Hwang, Chung-Yeon 대한한방안이비인후피부과학회 2005 한방안이비인후피부과학회지 Vol.18 No.2

Atopic Dermatitis is chronic eczematous dermatosis which is related strongly to a family history of atopic disease and hereditary disposition. Its threshold of itching is low so that severe itching occurs and causes secondary eczema. The purpose of this study was to estimate the efficiency of oriental medical treatment and management on atopic Dermatitis. We studied 2 patients who visited Wonkwang University Kwangju Oriental Hospital Dept. of Dermatol. with atopic dermatitis from April 2004 to February 2005. We treated him with herb-medication, acupuncture, negative therapy, full spectrum visible ray therapy(by carbon arc). We used the ADSI(Atopic Dermatitis Severity Index) to assess the severity of atopic dermatitis. The grade of the severity of atopic dermatitis was lower only by the traditional chinese medical treatments and management. Considering the above result, more study is needed the factors of increasing severity of atopic dermatitis, and the clinical interchange or atopic Dermatitis between oriental medicine and western medicine.

Effects of Trioctyl Phosphate and Cresyl Diphenyl Phosphate as Flame-Retarding Additives for Li-Ion Battery Electrolytes

심은기,남태흠,김정구,김현수,문성인 대한금속·재료학회 2009 METALS AND MATERIALS International Vol.15 No.4

Safety concerns related to lithium-ion batteries have been the key obstacle to their application in hybrid electric vehicles. Trioctyl Phosphate (TOP) and Cresyl Diphenyl Phosphate (CDP) were studied as potential flame-retarding additives for lithium-ion batteries. The electrochemical performance and thermal stability of the additive-containing electrolytes, in combination with a cell comprising a LiCoO2 cathode and Mesocarbon Microbeads (MCMB) anode, were tested in coin cells. Cyclic Voltammetry (CV), Differential Scanning Calorimetry (DSC), Electrochemical Impedance Spectroscopy (EIS), and Scanning Electron Microscopy (SEM) were used for the experimental analysis. The study results revealed that CDP addition at 5 wt.% improved the cell stability due to the lower rate of the charge-transfer resistance increase over 30-50 cycles. CDP was demonstrated to be a better flameretarding additive than TOP. Safety concerns related to lithium-ion batteries have been the key obstacle to their application in hybrid electric vehicles. Trioctyl Phosphate (TOP) and Cresyl Diphenyl Phosphate (CDP) were studied as potential flame-retarding additives for lithium-ion batteries. The electrochemical performance and thermal stability of the additive-containing electrolytes, in combination with a cell comprising a LiCoO2 cathode and Mesocarbon Microbeads (MCMB) anode, were tested in coin cells. Cyclic Voltammetry (CV), Differential Scanning Calorimetry (DSC), Electrochemical Impedance Spectroscopy (EIS), and Scanning Electron Microscopy (SEM) were used for the experimental analysis. The study results revealed that CDP addition at 5 wt.% improved the cell stability due to the lower rate of the charge-transfer resistance increase over 30-50 cycles. CDP was demonstrated to be a better flameretarding additive than TOP.

연구논문 - 생물공학분과 / 에너지 , 환경분과 / 유지 , 계면활성제분과 : 국내 상업용 알루미늄의 용해속도에 미치는 억제제의 영향

심은기,황영기 ( Eun Gi Shim,Young Gi Hwang ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1990 No.3

N/A Dissolution rate of the domestic commercial aluminium was measured in KOH solution in order to confirm its applicability as an electrode in an aluminium-air cell. This was also performed to control the dissolution rate by means of the addition of ZnO, ZnCO₃, or ZnAc as an inhibitor.

엉클어진 금속선 전극반응기를 이용한 아조염료 합성폐수의 전기화학적 처리에 관한 연구

심은기,강영립,이미경,방시욱,추석열,송승구,황영기 ( Eun Gi Shim,Young Reep Kang,Mi Kyung Lee,Si Wook Pang,Suek Yuel Choo,Seung Koo Song,Young Gi Hwang ) 한국화학공학회 1995 화학공학의이론과응용 Vol.1 No.2

Electrochemical Performance and Thermal Stability of Lithium-Ion batteries Containing Electrolyte Additives

심은기,남태흠,김정구,김현수,문성인 한국공업화학회 2007 한국공업화학회 연구논문 초록집 Vol.2007 No.1

흡착제를 이용한 수중의 미량이취물질 분석법 개발에 관한 연구

심은기,김은호,곽철,황영기 경남대학교 신소재연구소 1999 論文集 Vol.11 No.-

본 연구에서는 다양한 흡착제들과 추출용매들을 사용하여 이취물질의 효율적인 분석기술을 개발코자 하였다. Geosmin의 흡착능 실험에서는 XAD 수지계통이 월등히 우수한 흡착능을 가진 것으로 나타났으며, 이중에 XAD-2 수지는 시료 100ml 당 300mg을 투여하였을 때 Geosmin 흡착능이 가장 뛰어났다. 추출용매별 Geosmin의 추출능 실험에서 액/액 추출법으로 실험하였을 때 MTBE와 Dichloromethane은 48%, 47%로 거의 비슷한 회수율을 나타내었고, XAD-2 수지를 이용한 고/액추출법으 경우에는 MTBE가 94% 정도로 회수율이 가장 높았고, Dichloromethane 79%, n-Hexane 39%, Diethylether 35% 순으로 나타났다. 염석제(NaCl)를 첨가하였을 경우에 Geosmin의 회수율 실험에서 MTBE를 이용하여 액/액 추출법으로 실험하였을 때 염석제 5g 첨가시 회수율이 75%로 가장 높았고, XAD-2 수지를 사용한 고/액추출법의 경우에는 추출용매 MTBE와 Dichloromethane에 대해 염석제의 투여에 의한 회수율의 증가는 없는 것으로 나타났다. XAD-2 수지의 진탕시간별 Geosmin의 흡착실험에서는 24시간 동안에 Geosmin에 대한 흡착량에는 거의 큰 변화를 나타내지 않았다. 최적의 흡착제는 XAD-2 수지이고 용매는 MTBE가 가장 안정적이고 우수한 것으로 평가되었으며, 액/액 추출법의 경우에 염석제를 첨가하였을 때가 첨가하지 않은경우 보다 회수율이 높게 나타났다. 고상 추출시 분석감도도 용매만 사용하여 추출한 결과보다 2배 가까이 높게 나타나 극미량 함유물질 분석시 전처리 기술로 응용 가능한 것으로 평가되었다. Even if odorous compounds remain very low concentration in water. it cause strong odor. Because Geosmin and most of odorous compound had very low vaporization. those were difficult to analyze with GC/MSD and Purge & Trap. So. we needed pre-treatment method for decreasing amounts of extracting solvents, improving recovery efficiencies and increasing analytical efficiencies. This study developed efficient technology for analyzing odorous compounds, using various adsorbents and extracting solvents. The optimum adsorbent was XAD resins. Especially, SAD-2. XAD-7 and XAD-2010 were superior. but XAD-2 of these and the optimum extraction solvent is MTBE. Other extraction solvents' efficiency is in order of MTBE〉Dichloromethane〉n-Hexane〉Diethylether. The optimum NaCl dosage for increasing efficiency is 5g in liquid-liquid extraction method. The shaking time(0-24hr) has no concern with adsorption efficiency. The optimum adsorbent is SAD-2 resin and extraction solvent is MTBE. Dosing NaCl. adsorption efficiency is increased in liquid-liquid extraction method, but NaCl has no effect on liquid-solid extraction method. In this experimental results. this method will apply to not only Geosmin but other well-known odorous compounds (2-MIB, 1BMP. IPMP, TCA) and algae toxins (Mycrocystin. Anatoxin etc.).