• Bulletin of the Korean Chemical Society
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• v.21 no.2
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• pp.207-210
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• 2000

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.255-256
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• 1990

• Bulletin of the Korean Chemical Society
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• v.9 no.4
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• pp.260-261
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• 1988

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.88.2-88.2
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• 2011

본 연구는 아연/공기전지 설계기술 개발을 위한 기초 연구로서 전산해석을 이용하여 전해질 유동에 따른 아연/공기전지의 성능 예측에 관한 것이다. 전산해석모델은 전기화학 방정식과 유체유동 방정식으로 구성하였으며, 화학종 반응에 관한 지배방정식으로는 Nernst-Planck식을 이용하였고 전극표면의 전기화학반응은 Butler-Volmer식을 이용하였다. 또한 유체유동 방정식은 Navier-Stoke식을 적용하여 전해질 유동에 따른 전기화학적 성능 변화를 모사하였다. 아연/공기전지 성능 평가 실험으로부터 얻은 I-V 곡선과 전산해석결과와의 비교/분석을 통하여 전기화학모델의 타당성을 검증하였으며, 유체 유동 방정식과의 연동해석을 적용하여 전해질 유입 위치 및 유입 속도에 따른 아연/공기전지의 성능 변화를 조사하였다. 아연/공기전지의 성능은 전해질 유입 위치가 아연극에 가까울수록, 유입 속도가 빠를수록 향상되는 것을 확인할 수 있었다.

• Analytical Science and Technology
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• v.9 no.1
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• pp.72-77
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• 1996

In the process of solar energy conversion into electrical energy using the photoelectrochemical cell containing the sensitizer, rose bengal and supersensitizer. $I^-$, the photocurrent is stabilized and durable. But the long time span of irradiation causes the decrease of photocurrent monotonically. Spectroscopic and electrochemical analyses of rose bengal solution containing $I^-$ revealed that the decrease of concentration of rose bengal was attributed to the reaction of rose bengal in the dark with $I_2$ formed as a result of the possible photocatalytic reaction of rose bengal with $I^-$.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.176-185
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• 1995

To improve photosensisitizing efficiency of ZnO/$H_2Pc(I)_x$ system, ZnO/$H_2Pc(I)_x$ system was dispersed in a typical photoconductive polymer of poly(9-vinylcarbazole)(PVCZ). The iodine dopant level(x) of ZnO/${\chi}-H_2Pc(I)_x$ is proportional to concentration of iodine, whereas x of ZnO/${\beta}-H_2Pc(I)_x$ decreased from the highest x=0.97 at more than $6.3{\times}10^{-3}$ M iodine solution. The Raman spectra of ZnO/${\chi}-H_2Pc(I)_x$ at 514 nm exhibited characteristic $I_3^-$ patterns in the range of 50∼550 $cm^{-1}$ at $x{\geq}0.57.$ The surface photovoltage of ZnO/${\chi}-H_2Pc(I)_{0.48}$/PVCZ was approximately 1.6 times greater than ZnO/${\chi}-H_2 Pc(I)_{0.48}$ and was 1.8 times of ZnO/${\chi}-H_2Pc(I)_{0.57}$/PVCZ at 670 nm. With ZnO/$H_2Pc(I)_x$/PVCZ, the highest iodine dopant levels showed a higher photovoltage. Therefore the injection of holes from H2Pc into PVCZ resulted in that photosensisitizing effect of ZnO/$H_2Pc(I)_x$/PVCZ system was improved compared to ZnO/$H_2Pc(I)_x$ case.

• Journal of the Korean Chemical Society
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• v.19 no.5
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• pp.339-342
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• 1975

The rates of consumption of iodine and gas evolution in hydrazine-iodine reaction in the presence of large excess of hydrazine have been studied in the pH range 0.5${\sim}$7. They are the same at very low pH and both increase to respective asymptotic values as pH is increased. The rate of iodine consumption is three orders of magnitude faster than the rate of gas evolution at higher pH. The results are explained by postulating that $N_2H_4$ but not protonated form reacts with iodine and an intermediate, probably $N_2H_2I_2$, is formed which decomposed by first order reaction of rate constant about 1.5${\times}10^{-3}sec^{-1}$ in neutral and weakly acidic solutions.

• Journal of the Korean Chemical Society
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• v.24 no.1
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• pp.15-19
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• 1980

CNDO/2, EHT molecular orbital methods are used to investigate the electronic structure and reactivity of glycinato, glycine ester ligands. The results show that bidentate glycinato has a more stable structure, Gly-I with a $105.9^{\circ}$dihedral angle between ${\Delta}O_4C_3C_2$ and ${\Delta}C_3C_2N_1$ than Gly-Ⅱ. The electron inductive effects in the alkyl group substituted glycine ester ligands can also be derived from the calculation. According to the electron density, qN of ligands on the basis of CNDO/2 MO calculations, it is concluded that the stabilities are in the order of glycinato > Gly-Et-ester > Gly-i-Pr-ester > Gly-Me-ester.

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.19-25
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• 2002

We measured the variations of potentials and current densities for several polymers. The results were carefully examined to identify various factors such as temperature and pH to influence the potential and rate. The Tafel slope for anodic dissolution was determined by the polarization effect under these conditions. The optimum conditions were established for each case. The second anodic current density peak and maximum current density were designated as the relative polarization sensitivity $(I_r/I_f)$. The mass-transfer coefficient value $({\alpha})$ was determined by the Tafel slope for anodic dissolution on the basis of the polarization effect under optimum conditions.

• Journal of the Korean Chemical Society
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• v.25 no.4
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• pp.253-262
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• 1981

The AgI/ PV${\cdot}$THF membrane electrode could be used as an indicator electrode in the potentiometric titration of single halide and mixture halide solutions with the standard solution of silver nitrate. The errors in the stepwise titrations of mixture halide solutions were considerably large, but by addition of flocculating agent, such as $NaNO_3$ or $Ba(NO_3)_2$, in the sample solution, the errors were greatly reduced. Also, the effects of gelatin, filter paper and temperature on the titration errors were examined.