• 한국환경과학회지
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• 제16권4호
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• pp.441-447
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• 2007

This study was carried out to investigate the effect of electrochemical (EC) disinfection of artificial wastewater contaminated by Escherichia coli culture. Circulated batch type electrochemical disinfection system using three plates electrodes was used. Also, the several factors (pH, ORP, DO, temperature, current, conductivity) were measured in order to investigate the fundamental design factor in the EC disinfection system. It was demonstrated that the EC process was highly effective for wastewater disinfection. At the constant voltage, the disinfection efficiency was increased according to time. The disinfection efficiency and current increased as the increase of voltage. The variation of conductivity was a little related to the variation of CFU (colony forming units). The differences in disinfection efficiency according to the ice pack and the variation of electrodes were not occurred. The EC disinfection efficiency and current increased according to the increase of circulating flow rate.

• 대한화학회지
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• 제55권2호
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• pp.169-176
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• 2011

N,N-bis(2,5-di-tert-butylphenyl) - 3,4,9,10 perylenebis(dicarboximide) 레이저 염료에 대한 전기화학적 연구가 0.1 M tetrabutyl ammonium perchlorate(TBAP)/1,2 dichloroethane($CH_2Cl-CH_2Cl$) 용액내에서 백금 전극을 이용하여 순환 전압-전류법 및 디지털 시뮬레이션 기술과 결합된 convolution-deconvolution 전압-전류법으로 수행되었다. 연구에 사용된 염료는 두개의 전자를 순차적으로 소모하며 radiacal anion과 dianion으로(EE 메커니즘) 환원되었다. 전위를 positive scan으로 전환하면, 이 화합물은 두 개의 전자를 잃고 산화된 뒤 빠른 응집 과정($EC_1EC_2$ 메커니즘)을 거치게 된다. 이 화합물의 전극 반응 경로, 화학 및 전기화학적 파라미터는 순환 전압-전류법과 convolutive 전압-전류법을 이용하여 측정되었다. 이렇게 구한 전기화학적 파라미터는 디지털 시뮬레이션 방법을 통하여 검증되었다.

• 마이크로전자및패키징학회지
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• 제21권3호
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• pp.19-24
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• 2014

This article reviews the recent progress in nanowell array biosensors that use the label-free detection protocol, and are detected in their natural forms. These nanowell array biosensors are fabricated by nanofabrication technologies that should be useful for developing highly sensitive and selective also reproducible biosensors. Moreover, electrochemical method was selected as analysis method that has high sensitivity compared with other analysis. Finally, highly sensitive nanobiosensor was achieved by combining nanofabrication technologies and classical electrochemical method. Many examples are mentioned about the sensing performance of nanowell array biosensors will be evaluated in terms of sensitivity and detection limit compared with other micro-sized electrode without nanowell array.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2016년도 추계학술대회 논문집
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• pp.115.1-115.1
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• 2016

Electrochemical anodization has been interested due to its useful way for the nano-scale architecture of metal oxides obtained from a metal substrate. By using this method, it is easy to control the morphology of the oxide materials by controlling electrochemical conditions. Among oxide materials obtained from the transition metals such as Ti, V, W, etc., in this paper, the morphological study of anodized $TiO_2$ was employed at various voltage conditions in fluoric based electrolyte, and the effects of applied voltage (sweep rate and retention time) on the tube morphologies were investigated. Furthermore, by using anodization of tungsten substrate (W), we fabricated the porous structure of $WO_3$ and provided merits of tailored structure for the hybridization of inorganic and organic materials as electrochromic (EC) applications. The hybrid porous $WO_3$ shows multi-chromic properties during the EC reactions at specific voltage conditions. From these results, the anodization process with tailoring nano-structure is one of the promising methods for EC applications.

• Journal of Electrochemical Science and Technology
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• 제12권1호
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• pp.21-32
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• 2021

This study reports for the first time the application of electrocoagulation (EC) from laboratory to pilot scales for the treatment of printing wastewater, a hazardous waste whose treatment and disposal are strictly regulated. The wastewater was taken from three real printing companies with strongly varying characteristics. The treatment process was performed in the laboratory for operational optimization and then applied in the pilot scale. The weight loss of the electrode and the generation of sludge at both scales were compared. The results show that the raw wastewater should be diluted before EC treatment if its COD is higher than about 10,000 mg/L. Pilot scale removal efficiencies of COD and color were slightly lower compared to those obtained from the laboratory scale. At pilot scale, the effluent CODs removal efficiency was 81.9 - 88.9% (final concentration of 448 - 992 mg/L) and color removal efficiency was 95.8 - 98.6% (final level of 89 - 202 Pt-Co) which proved the feasibility of EC treatment as an effective pre-treatment method for printing wastewater as well as other high colored and hard-biodegradable wastewaters.

• 센서학회지
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• 제32권6호
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• pp.412-417
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• 2023

There is increasing interest in the rapid and highly sensitive monitoring of cell viability in biological and toxicological research. Conventional methods depend on optical assays using Water Soluble Tetrazolium-8 (WST-8) or 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay, which requires a large volume of samples and special instruments, necessitating shipment of clinical samples to laboratories. This paper reports on the development of a rapid and sensitive electrochemical (EC) sensor using screen printed electrode (SPE) and surface modification using 4'-mercapto-N-phenylquinone diamine (4'-NPQD), as double electron mediators, for monitoring cell viability via the measurement of nicotinamide adenine dinucleotide (NADH). We used the sensor to observe the viability of MCF-7 and doxorubicin (Dox)-treated cells. The oxidation current of NADH was measured via chronoamperometry (CA), and the EC results showed a good linear relationship when compared with NADH quantification using WST-8 assay. The analysis time was only 10 s and limit of detection (LOD) of NADH was 1.78 µM. Our EC method has the potential to replace conventional WST assays for cell viability and cytotoxicity experiments.

• 한국표면공학회지
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• 제36권4호
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• pp.307-316
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• 2003

Salt spray, CASS(copper accelerated acetic salt spray) and EC(electrolytic corrosion) tests were performed in order to evaluate the corrosion resistance of plated Ni and Ni-Cr layers on Fe substrate. Compared with the conventional methods such as salt spray and CASS, the electrochemical method such as EC test may be beneficial in terms of test time span and quantitative accuracy. Furthermore, EC test can also become the alternative method to evaluate the resistance to corrosion of coatings by measuring the corrosion potentials of the coated layers in the electrolyte during the off-time of EC cycles. Compared with the corrosion potentials of pure iron, nickel, chromium, those potentials of coated layers can be used to anticipate the extent of corrosion. Results showed that in terms of the test time span, EC test gave 14 times and 21 times faster results than the salt spray test in cases of $5\mu\textrm{m}$ Ni and $20\mu\textrm{m}$ Ni plated layers, respectively. In addition, EC test also offered the shorter test time span than CASS test in cases of $5 \mu\textrm{m}$ Ni + $0.5\mu\textrm{m}$ Cr, and $20\mu\textrm{m}$ Ni + $0.5\mu\textrm{m}$ Cr on Fe substrate by 78 times and 182 times, respectively. Therefore, EC test can be regarded as the better method to evaluate the resistance to corrosion of coated layers than the conventional methods such as salt spray and CASS.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.121-124
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• 1998

The purpose of this study is to research and develop solid polymer electrolyte(SPE) for Li secondary battery. This paper describes temperature dependence of conductivity, impedance spectroscopy, electrochemical properties of PVDF electrolytes as a function of a mixed ratio. Polyvinylidene(PVDF) based polymer electrolyte films were prepared by thermal gellification method of preweighed PVDF, plasticizer and Li salt. The conductivity of PVDF electrolytes was 10$\^$-3/S/cm. 25PVDFPC$\_$10/EC$\_$10/LiClO$_4$ electrolyte shows the better conductivity of the others. 25PVDFPC$\_$10/EC$\_$10/LiClO$_4$electrolyte remains stable up to 4.7V vs. Li/Li$\^$+/. Steady state current method and ac impedance used for the determination of transference numbers in PVDFD electrolyte film. The transference number of 25PVDFPC$\_$10/EC$\_$10/LiClO$_4$electrolyte is 0.58.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.374-377
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• 1999

The purpose of this study is to research and develop solid polymer electrolyte(SPE) for Li polymer battery. This paper describes temperature dependence of conductivity, impedance spectroscopy, electrochemical properties of PVDF/PAN electrolytes as a function of a mixed ratio. PVDF/PAN based polymer electrolyte films were prepared by thermal gellification method of preweighed PVDF/PAN, plasticizer and Li salt. The conductivity of PVDF/PAN electrolytes was 10-3S/cm. 20PVDF5PANLiCIO$_4$PC$\sub$10//EC$\sub$10/ electrolyte shows the better conductivity of the others. 20P7DF5PANLiCI$_4$PC$\sub$10//EC$\sub$10/ electrolyte remains stable up to 5V vs. Li/Li$\^$+/. Steady state current method and ac impedance used for the determination of transference numbers in PVDF/PAN electrolyte film. The transference number of 20PVDF5ANLICIO$_4$/PC $\sub$10//EC$\sub$10/ electrolyte is 0.48

• Corrosion Science and Technology
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• 제12권1호
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• pp.56-64
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• 2013

An Eectrolytic Corrosion(EC) test method was evaluated by the comparison with Copper Accelerated Acetic Salt Spray(CASS) and Neutral Salt Spray(SS) tests. Those methods were applied in order to evaluate corrosion resistance of Ni-Cr plated and Zn-plated Fe substrates. The correlations between results obtained by different test methods were investigated. Results showed that the electrochemical method such as the EC test method was superior to the conventional methods such as CASS and SS, in terms of the quantitative accuracy and the test-time span. Furthermore, the EC test method provided the useful means to estimate the initiation of corrosion of each layer by monitoring the rest potentials of the coated layers such as Ni, Cr, and Zn on Fe substrate. With regard to test time spans, the EC test provided the 78 times and 182 times faster results than the CASS test in cases of $Fe+5{\mu}m$ $Ni+0.5{\mu}m$ Cr and $Fe+20{\mu}m$ $Ni+0.5{\mu}m$ Cr respectively, while the EC test was 85 times faster results than the Salt Spray test in the case of $Fe+20g/m^2$ Zn. Therefore, the EC test can be the better method to evaluate the resistance to corrosion of coated layers than the conventional methods such as the SS test and the CASS.