• 한국식품영양학회지
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• 제13권4호
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• pp.360-364
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• 2000

유지에 존재하는 linoleic acid의 전기화학적 산화/환원으로부터 속도론적 인자를 예측하고, 시간 변화에 대한 산패 정도를 조사하였다. Linoleic acid의 전기 화학적 산화환원 반응은 비가역적이고, 확산지배적으로 진행됨을 알 수 있고, 주사속도에 따른 결과로부터 확산계수 $D_{o}$ 는 2.61$\times$$10^{-6}$이고, 속도상수 $K^{o}$ 는 9.79$\times$$10^{-11}$로 주어짐을 예측하였다. 또한 linoleic acid의 산화반응 영역과 환원반응 영역에서 작업전극의 선택도가 달라짐을 볼 수 있다. 대기중 방치시간에 따른 시험 결과 방치한 지 4일을 전후로 산화 peak가 최대값으로 주어졌다. 특정 Peak에서 일정전위 전기분해 한 후 전기분해 생성물을 분석한 결과 carbonyl group이 생성됨을 예측할 수 있었다.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권3호
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• pp.165-171
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• 2000

Experiments were carried out to measure variations in the oxidation potential and current density using the polarization curves of polycarbonate. The results were then examined to identify the influences affecting the oxidation potential related to various conditions, such as temperature, pH, and oxydase(citrate and lipase). The lines representing the active anodic and cathodic dissolution shifted only slightly in the potential direction relative to temperature, pH, and the effect of the enzyme. The Tafel slope for the anodic and cathodic dissolution was determined such that the reversibility polarization was indicated as being effected by various conditions. The slope of the polarization curves describing the active-to-passive transition region shifted noticeably in their direction. Also, by varying the conditions, the optimum conditions for the most ready transform were identified, including temperature, pH, oxidation rate, and resistance of oxidation potential. The critical oxidation sensitivity(I(sub)r/I(sub)f) of the anodic current density peak and maximum passive current density was also determined, which is used in measuring the critical corrosion sensitivity of a polycarbonate.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권4호
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• pp.255-261
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• 2000

Experiments were carried out to measure the corrosion potential and current density variations in the polarization curves of polypropylene. In particular, the results were examined to identify those influences affecting the corrosion potential, such as temperature, pH, salt, and oxygen. The Tafel slope for the anodic dissolution was determined based on the polarization effect under various conditions. Furthermore, the optimum conditions for the most rapid transformation were establish based on a variety of conditions, including temperature, pH, corrosion rate, and resistance of corrosion potential. The second anodic current density peak and maximum passive current density were designated as the critical corrosion sensitivity(I(sub)r/I(sub)f). This I(sub)r/I(sub)f value was then used to measure the critical corrosion sensitivity of polypropylene. The potentiodynamic parameters of corrosion were obtained using a Tafel plot.

• 한국인쇄학회지
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• 제8권1호
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• pp.53-70
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• 1990

It is well known that viologens such as 1.1 - disubstituted 4, 4` - bipyridinium salts and those used as redox indicator, herbicide and electrocheromic display device because those possess the lowest redox potential in any organic system. Viologen salts produced reversible high blue color under the influence of radical cation by photoreduction This study is related to the synthesis of viologen derivatives and the photoreduction property in water solution stats and the polar aprotic polyvinylpyrrolidone(PVP) matrix.

• Journal of Electrochemical Science and Technology
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• 제3권2호
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• pp.85-89
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• 2012

This study demonstrates the direct anodic electrodeposition of polypyrrole (PPy), poly(3,4-ethyl-enedioxythiophene) (PEDOT), and polythiophene (PTh) on Cu electrodes by employing a corrosion inhibitor, succinonitrile (SN). SN was found to suppress anodic Cu dissolution beyond the oxidation potential of the polymer monomers. It is also revealed that the Cu surface passivated by SN is still adequately conductive to allow the redox reaction of 1,4-difluoro-2,5-dimethoxybenzene (FMB) and the oxidation of the polymer monomers. Through both cyclic voltammetry and galvanostatic techniques, PPy, PEDOT, and PTh films were successfully synthesized on Cu electrodes in the presence of SN, and the redox behaviors of the films were evaluated.

• 한국세라믹학회지
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• 제45권7호
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• pp.375-379
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• 2008

Redox behavior was observed in alkali alkaline earth silicate PDP (Plasma Display Panel) glass melts doped with sulfate and sulfide by square wave voltammetry (SWV). According to voltammograms produced at a temperature range of 1100 to $1400^{\circ}C$ and frequency range of 5 to 1000 Hz, both melts showed the same behavior in which there is one reduction peak at low frequency but another peak at an increase of frequency. Based on the frequency dependence of the peak current, self diffusivity of $S^{4+}$ was determined. Based on the temperature dependence of the peak potential, standard enthalpy (${\Delta}H^0$) and standard entropy (${\Delta}S^0$) for the reduction of $S^{4+}$ to $S^0$ were calculated.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.448-451
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• 2002

The possibility of using polypyrrole as a drug delivery system(DDS) has been studied using indicate (Phenol red) and substance with therapeutic activity(Sodium salicylate). In aqueous solution, negative potential is applied to polypyrrole then anion(with therapeutic activity) of sodium salicylate is released by redox processes of polypyrrole. The release amount of anionic drugs from polypyrrole is measured by UV-visible spectrometer which can measure UV-absorbance of materials. Electrode area that use for release amount measurement is$50mm^{2}(5{\times}10mm)$,and thickness of polypyrrole membrane is $15{\mu}m$. DC 1V applied in saline solution, the release amount according to time increased gradually. In various electrode area, release amount of anionic drug is directly to electrode area.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.544-547
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• 2000

Polypyrrole (PPy) was chemically synthesized within the pores of nanoporous polycarbonate (PC) Particle Track-etched Membranes (nano-PTM). Hollow tubules are formed because polypyrrole initially deposits on the surface of the pores walls. By running successive syntheses, we have obtained wires (filled tubules). The redox property of PPy nanotubules was investigated by cyclic voltammetry. The redox potential was lowered as much as 0.5V vs. Ag/AgC1, comparing with electrosynthesized PPy film. It suggests that an electron hopping mechanism of PPy nanotubules was improved. Electric conductivity of PPy nanotubules and nanowire was evaluated. We obtained good electric conductivity of PPy nanotubules even in the neutral state. The conductivity and activation energy were $10^1$ order at the room temperature and 25.3 meV respectively.

• 대한기계학회논문집B
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• 제40권12호
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• pp.769-776
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• 2016

본 연구는 화학종을 포함한 반응을 위해 종합적인 보존법칙과 운동학적 모델을 사용하여 수치해석을 진행하였다. 삼차원 형상으로 전극 전위, 바나듐 이온농도, 과전압 그리고 저항손실을 계산하였다. 셀의 온도, 초기 바나듐 이온농도를 변수로 설정하고 각 변수에 따른 전압과 손실을 계산하였다. 계산된 양극, 음극에서의 과전압과 전해액 상의 저항 손실을 통해 각각의 변수가 바나듐 레독스 플로우 배터리의 전기화학적 성능에 미치는 영향을 수치해석적으로 예측하고 분석하였다. 셀의 온도가 $20^{\circ}C$에서 $80^{\circ}C$로 증가되면 전압효율은 89.34%에서 87.29%로 2.05% 감소한다. 바나듐 농도가 $1500mol/m^3$에서 $3000mol/m^3$으로 증가되면 전압효율은 88.65%에서 89.25%로 0.6% 상승하였다.

• 한국수소및신에너지학회논문집
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• 제24권4호
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• pp.347-352
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• 2013

Four types of electrolyte were tested for the application as an electrolyte in the Zn-Br redox flow battery. Electrolyte was consist of $ZnBr_2$ (electrolyte number 1), $ZnBr_2+KCl$ (electrolyte number 2), $ZnBr_2+KCl+NH_4Br$ (electrolyte number 3) and $ZnBr_2+KCl+EMPBr(C_7H_{16}BF_4N)$ (electrolyte number 4). The each electrolyte property was measured by CV (cyclic voltammetry) method. The different between the potential of anodic and cathodic maximum current density in a CV experiment (${\Delta}E_P$) was 0.89V, 0.89V, 1.06V and 0.61V for the electrolyte number 1, 2, 3 and 4, respectively. The electrolyte involved KCl increased conductivity which was appeared by anodic and cathodic maximum current density in a CV experiment. It was estimated that the electrolyte of number 3 ($ZnBr_2+KCl+NH_4Br$) and number 4 ($ZnBr_2+KCl+EMPBr$) could be suitable as an electrolyte in the Zn-Br redox flow battery with non-appeared bubble, non-Br formation and high anodic-cathodic maximum current density.