• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.289-289
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• 1994

흰쥐 적출 대동맥을 이용하여 혈관근의 $Na^{+}$/$Ca^{2+}$ 교환계의 기능과 성질을 구명코자 $Na^{+}$/$Ca^{2+}$ 교환계를 통한 수축 반응을 관찰하고 이때의 조직내 $Ca^{2+}$ 농도, cGMP 농도 및 이 수축에 대한 차단제와 저산소 처리의 영향을 조사하였다. 흰쥐 적출 대동맥은 $Na^{+}$ free 영양액하에서 수축반응을 일으켰고 이 수축 반응 ($Na^{+}$ free 수축반응)은 KCl 농도 증가에 비례하여 증가하였다. KCI 21.6mM 하의 $Na^{+}$ free유발 수축반응은 amiloride전처리하에서 용량-의존성으로 억제되었고 특히 tonic 수축반응이 예민하게 소실되었으며, benzamil과 verapamil 전처리하에서도 유의하게 억제되었다.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.123-130
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• 2005

Zeolite X adsorbents with large surface area were prepared for using oxygen PSA adsorbent. Selective adsorption performance of nitrogen on the synthesized zeolite X adsorbent was improved by the cation exchange of adsorbent. The zeolite X which had over $650m^2/g$ surface area was synthesized at the conditions of $SiO_2\;:\;Na_2O\;:\;H_2O\;:\;Al_2O_3$ = 2.5 : 3.5 : 150 : 1 mole ratio, $98^{\circ}C$ temperature and 18 h synthesized time in 50 L reactor. The metal ions Li, Ag, Ca, Br, Sr, etc. were investigated for ion exchange with zeolite X. Ag ion was showed the highest ion exchange rate among these metal ions and all metal ions were exchanged with Na ion at equivalent rate. Compared with the NaX adsorbent, the ion exchanged zeolite X adsorbent remarkably improved its adsorption performance of nitrogen at the conditions of $10{\sim}40^{\circ}C$ temperature and 0~9 atm pressure. At an equilibrium pressure under 0.5 atm, adsorption performance of nitrogen on the ion exchanged zeolite adsorbent increased in the order of Ag > Li > Ca > Sr> Ba > K, whereas at an equilibrium pressure over 1 atm showed in the order of Li > Ag > Ca > Sr > Ba > K. Nitrogen/oxygen separation factor of Li ion exchanged zeolite X adsorbent was 13.023 at the partial pressure of nitrogen/oxygen gas mixture similar to air and $20^{\circ}C$ adsorption temperature.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.195-195
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• 2011

공기 중 산소를 이용한 다양한 산화반응에 적합한 이종상 촉매 개발이 공업적으로나, 학문적으로 중요한 의미를 갖는다. 우리는 수산화 인회석(hydroxyapatite, HAP)에 Cu이 도입된 새로운 이종상 촉매를 합성하였으며, 이를 이용하여 Mesitylene의 산화반응을 통해 반응성을 관찰하였다. 전이금속 Cu를 이온교환 반응 하는 과정에서 온도와 압력조건의 변화가 촉매의 활성에 미치는 영향에 대해 연구하였다. 반응 후의 생성물질은 GC/MS를 통해 알아내고 Mesitylene 이외에 벤젠고리에 치환된 알킬기의 수가 다른 물질의 산화반응을 수행하였다.

• Proceedings of the KAIS Fall Conference
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• 2008.11a
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• pp.419-422
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• 2008

ETA(Ethanolamine, 에탄올아민)는 Amine의 일종으로 정밀화학 제품의 중간원료로서 화학제품 제조나 비행기 기관 및 원전 2차계통의 부식방지제, 이산화탄소와 같은 산성 성분을 흡수하는 흡수제로 각종 산업에서 다양하게 사용되고 있는 화학물질이다. 이러한 ETA는 탄소와 질소, 산소로 이루어진 매우 안정된 유기화합물로 상온에서는 휘발성을 띠지만, 산/염기 평형상수가 9 이상이므로 9 이하일 경우에는 수중에 존재하며 COD 및 T-N을 유발하므로 제거해야 한다. 따라서 본 연구에서는 수중에 존재하는 ETA를 제거하기 위해 온도와 농도에 따른 양이온교환 및 재생용액의 농도, 반응시간에 따른 양이온 교환수지 재생특성을 조사하였다. 양이온교환 수지의 이온교환능력은 ETA의 농도 및 온도에 영향을 받았으며 농도와 온도가 증가할수록 파과시간은 단축되었다. 양이온교환 수지의 재생효율은 재생액의 농도 및 반응시간에 영향을 받았으며, 재생액의 농도 및 반응시간이 증가할수록 재생효율은 증가하였다.

• Journal of Energy Engineering
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• v.6 no.1
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• pp.26-33
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• 1997

Highly crystalline Cu-ZSM5 was prepared without using organic templates. Several ion exchange treatments between Na$\^$＋/ and Cu$\^$2＋/ brought about excess loading of copper ions on the ZSM5 zeolite and the resultant zeolite was active for the decomposition of NO. This indicates that the copper ions excessively loaded on the ZSM5 zeolite are effective for the NO decomposition. When oxygen was added to a reactants, the conversion of NO decreased. NO, O$_2$TPD experiments explained that the active sites for NO decomposition and the adsorption sites of O$_2$, were the same. O$_2$, at the surface of ZSM5 zeolite was desorbed incompletely after pretreatment at 500$^{\circ}C$, and CU-ZSM5 pretreated with H$_2$at 500$^{\circ}C$ showed promoted activity at the start of reaction. Thus, it seems clear that O$_2$, adsorbed ai the surface of catalyst inhibits the catalytic activity.

• Analytical Science and Technology
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• v.11 no.6
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• pp.460-468
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• 1998

Schiff base ligands such as $SOPDH_2$, $SNDH_2$, $EBNH_2$, and $PBNH_2$ and their Co(II) complexes such as [$Co(II)(SND)(H_2O)_2$], [$Co(II)(SOPD)(H_2O)_2$], [$Co(II)(EBN)(H_2O)$], and [$Co(II)(PBN)(H_2O)$] have been synthesized. The mole ratio of Shiff base ligand to cobalt(II) for the Co(II) complexes was found to be 1:1. Also these complexes have been configurated with hexa-coordination. Reduction of dioxygen was investigated by cyclic voltammetry at glassy carbon electrodes modified with Schiff base Co(II) complexes in 1 M KOH aqueous solution. At modified glassy carbon electrode with Schiff base Co(II) complexes, reduction peak current of oxygen was increased and peak potential was shifted to more positive direction compared to bare glassy carbon electrode. The electrokinetic parameters such as number of electron and exchange rate constant were calculated from the results of cyclic voltammogrms. The reduction of dioxygen at glassy carbon electrode has been $2e^-$ reaction pathway. Exchange rate constant at glassy carbon electrode modified with Co(II) complexes was increased 2~10 times compared to bare electrode.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.116-116
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• 2011

바이오 가스 플랜트의 혐기소화 공정에서 발생하는 바이오 가스는 중 유해가스인 황하수소($H_2S$)는 부식성 가스로 수천 PPM농도를 함유하여, 발전기나 가스보일러로 이용하는 경우에는 $H_2S$를 제거하는 탈황공정이 반드시 필요하다. 탈황방식에는 산화철 탈황(건식 탈황)과 생물 탈황이 현재 많이 사용되고 있어나 산화철 탈황은 산화철 pellet이 유화철에 변화하면 탈황능력이 저하되어 pellet을 교환해야 하며 많은 비용이 발생한다. 생물 탈황 방식은 유황산화세균의 서식활동조건(온도, 반응시간, 산소량)확보가 반드시 필요하여 높은 운전기술을 필요로 한다. 본 연구에서는 바이오가스 전처리 기술 중 활성탄 또는 약액을 이용한 기존의 탈황정제방식보다 흡착성능이 뛰어난 이온교환섬유를 이용하여, 황화수소($H_2S$)를 95% 이상 제거할 수 있는 고효율 섬유상 이온촉매 악취제거 시스템 개발을 수행하였다. 이온교환섬유는 방사선 조사를 이용하여 부직포에 라디칼을 인위적으로 형성시켜(그라프트 중합) 양이온 또는 양이온을 교환할 수 있도록 제조된 섬유상의 흡착제로, 이온교환 섬유의 화학적 이온교환과 물리적 흡착 및 탈착반응이 동시에 발생되고, 활성탄/실리카켈 보다 흡착능력이 2~4배 높다. 또한 이온섬유의 재생기능을 이용하여 장기적 다양한 악취($H_2S$, $NH_3$, 아민계, 메르갑탄류, 알데히드 등) 및 유해가스(VOCs, NOx, SOx) 등을 95% 이상 제거할 수 있다.

• Journal of the Korean Electrochemical Society
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• v.25 no.2
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• pp.69-80
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• 2022

The anion exchange membrane (AEM) water electrolysis for high purity hydrogen production is attracting attention as a next-generation green hydrogen production technology by using inexpensive non-noble metal-based catalysts instead of conventional precious metal catalysts used in proton exchange membrane (PEM) water electrolysis systems. However, since AEM water electrolysis technology is in the early stages of development, it is necessary to develop research on AEM, ionomers, electrode supports and catalysts, which are key elements of AEM water electrolysis. Among them, current research in the field of catalysts is being studied to apply a previously developed half-cell catalyst for alkali to the AEM system, and the applied catalyst has disadvantages of low activity and durability. Therefore, this review presented a catalyst synthesis technique that promoted oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) using a non-noble metal-based catalyst in an alkaline medium.

• Journal of the Korean Chemical Society
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• v.38 no.1
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• pp.41-49
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• 1994

Exchange reaction mechanisms of the Pb(II) ion for the complexes between Pb(II) ion and nitrogen oxygen donor macrocyclic ligands, such as 1,13-diaza-3,4 : $1011-dibenzo-59-dioxacyclohexa-decane(NtnOtnH_4)$, 1,15-diaza-3,4 : $1213-dibenzo-5811-trioxacycloheptadecane(NenOdienH_4)$, and 1,15-diaza-3,4 : $1213-dibenzo-5811-trioxacyclooctadecane(NtnOdienH_4)$, were studied by $^{207}Pb-NMR$ spectroscopy in N,N'-dimethylformamide(DMF) solutions. The associative-dissociative mechanism dominated in $NtnOtnH_4-Pb(II)$ and $NtnOdienH_4-Pb(II)$ system. For $NenOdienH_4-Pb(II)$ system, the bimolecular exchange mechanism prevailed below $-5^{\circ}C$, and both bimolecular exchange and associative-dissociative mechanism dominated above $+5^{\circ}C.$ The order of activation energies for dissociation was $NtnOdienH_4\;<\;NtnOtnH_4\;<\;NenOdienH_4$ which was reverse to the order of stabilities.

• The Journal of the Petrological Society of Korea
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• v.13 no.4
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• pp.214-223
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• 2004

Oxygen and hydrogen isotopic compositions of the Jurassic peraluminous Hwacheon granite were measured, and compared with those of other Jurassic peraluminous Daebo granite in Korea. $\delta$$\^$18/O values for quartz and feldspar of the Hwacheon granite range from 8.2 to 10.6 and 5.8 to 9.0$\textperthousand$, respectively. Whole rock $\delta$$\^$18/O values for banded biotite gneiss country rocks surrounding the Hwacheon granites range from 8.1 to 9.4$\textperthousand$. Whole rock and biotite $\delta$D Values for Hwacheon granite range from -84 to -113 and -107 to -113$\textperthousand$, respectively. Whole rock $\delta$D values for banded biotite gneiss country rocks range from -76 to -100$\textperthousand$. Both $\delta$$\^$18/O and $\delta$D values of the Hwacheon granite are characterized by low values compared to the 'normal' values for the fresh peraluminous granitic rocks. Low $\delta$$\^$18/O values of the Hwacheon granite resulted from fluid-rock interaction for a long period. Isotopic modelling result renders that a relatively low-$\delta$$\^$18/O fluid below -1$\textperthousand$ was involved in subsolidus isotopic exchange under a relatively high fluid/rock ratio (<-6). The fluid of meteoric origin has experienced a modification of oxygen isotopic composition as a result of fluid-rock interaction with the Hwacheon granite and surrounding metapelitic country rocks.