• Journal of the Korean Chemical Society
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• v.46 no.3
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• pp.225-228
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• 2002

Poly-o-toluidine (POT) was chemically and electrochemically synthesized for the study of the electronic and steric effect of methyl substituents. It was found that the steric effect was dominant in POT. The IP 4.95 eV, EA 3.24 eV, Eg 1.71 eV of POT were found by the CV (Cyclic Voltammetry) and CCPSA (Constant Current Potentiometric Stripping Analysis).

• Journal of the Korean Applied Science and Technology
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• v.29 no.3
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• pp.443-449
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• 2012

A investigation of electrochemical analysis of antibiotics Neomycin ($C_{23}H_{46}N_6O_{13}$) was searched using electrochemical square wave (SW) stripping and cyclic voltammetry (CV) using working sensor of the modified carbon nanotube combination electrodes, optimum diagnostic parameters were searched by anodic stripping, final conditions were attained to working range of 1.0-14.0 ng/L, detection limit (S/N) was found to be 0.6 ng/L. The developed method was discovered to be fitting in quality control in the food, pharmaceutical and other manufacturing sectors.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.404-408
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• 2003

In this study, we examined the influences of pH and total concentration on the speciation of heavy metals (Cd, Cu, Zn) in acid mine drainage. Their labile concentrations were analyzed by Anodic Stripping Voltammetry (ASV) at both natural pH and adjusted pHs (from 2 to 8). We obtained regression equations for predicting labile concentrations as a function of the water pH and contamination level (total dissolved metal concentration). Our data show that labile Cu depends on both the total concentration and pH, while labile Cd and Zn concentrations are controlled mainly by their total concentration rather than pH. Therefore, the pH variation of AMD may significantly change the toxicity and bioavailability especially of Cu, owing to its speciation change.

• Journal of the Korean Chemical Society
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• v.63 no.1
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• pp.45-50
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• 2019

Because arsenic (As) is a chemical substance toxic to humans, there have been extensive investigations on the development of As detection methods. In this study, the electrochemical determination of As on nanoporous gold (NPG) electrodes was investigated using anodic stripping voltammetry. The electrochemical surface area of the NPG electrodes was controlled by changing the reaction times during the anodization of Au for NPG preparation, and its effect on the electrochemical behavior during As detection was examined. The detection efficiency of the NPG electrodes improved as the roughness factor of the NPG electrodes increased up to around 100. A further increase in the surface area of the NPG electrodes resulted in a decrease of the detection efficiency due to high background current levels. The most efficient As detection efficiency was obtained on the NPG electrodes prepared with an anodization time of 50 s. The effects of the detection parameters and of the Cu interference in As detection were investigated and the NPG electrode was compared to flat Au electrodes.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.30-30
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• 2018

스마트 도금공장을 구축하기 위해서는 도금액 내부의 화학 물질 농도 변화를 측정할 수 있는 화학 센서 기술이 필수적으로 요구된다. 와트욕은 대표적인 고속 니켈 도금액 중 하나로 기본적으로 황산니켈, 염화니켈, 보릭산의 염과 함께 케리어(type-1 광택제), 광택제(type 2-광택제), 응력 제어제 등의 유기 첨가제로 구성되어 있다. 이러한 유기 첨가제는 전차된 니켈층의 두께 균일도, 조도, 미세 구조, 내부 응력 등 다양한 특성을 제어하며, 정밀한 농도 관리가 필수적으로 요구되나, 분석 기술의 부재로 인하여 지금까지도 대부분의 액관리는 할셀법이나 작업자의 경험에 의존하고 있다. Cyclic voltammetry stripping(CVS) 방법은 전기화학 분석 과정에서 나타나는 첨가제의 가속, 감속 특성 등과 여기에 수반되는 stripping peak의 변화를 이용하여 개별 첨가제의 농도를 측정하는 방법이며, 지금까지 인쇄회로기판의 비아필 공정, 전해 동박 제조, 반도체 배선 등 구리도금 산업 전반에 걸쳐 첨가제 관리에 효과적으로 적용되고 있다. 그러나 수소 발생으로 인한 stripping 효율 문제로 인하여 니켈, 주석, 아연 등 표준 환원 전위가 높은 금속 도금액 내부 첨가제 농도 측정은 아직 어려운 상황이다. 본 연구에서는 이 문제를 극복하기 위해 염소를 과량 첨가한 구리 도금액을 CVS 분석의 base 용액으로 이용하여 니켈 도금액 내부 여러 광택제 (polyetylene glycol(PEG) 계열, thiourea 계열, 2-butyne-1,4-diol 등) 농도를 측정하는 법을 제시하였다. 제시된 방법은 CVS 분석 과정에서 구리-염소 사이의 상호 작용으로 인해 생성되는 3가지 stripping peak의 상대적인 크기 변화가 첨가제 농도에 따라 영향을 받는다는 사실에 기반하였다. 본 연구에서는 여기에 관한 원인에 대해 고찰하였으며, 제시된 방법을 통해 광택제 계열 첨가제 농도 측정을 선택적으로 할 수 있다는 것을 증명하였다.

• Journal of the Korean Chemical Society
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• v.51 no.5
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• pp.412-417
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• 2007

A simple prepared paste electrode (PE) of DNA immobilized on a carbon nanotube was utilized for monitoring the antibacterial agent oxytetracycline (OTC), using square-wave anodic stripping voltammetry (SWASV) and cyclic voltammetry (CV). Given these conditions, SWASV and CV working ranges were observed within 1-10 ngL-1 OTC. In the SWASV and CV for OTC concentrations of 0.1 mgL-1, the relative standard deviations (n=15) were 0.068 and 0.067, respectively. At the optimized condition, the detection limit was found to be 0.4 ngL-1 OTC. This method was applied to the hatchery fish tissue.

• Journal of the Korean Chemical Society
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• v.32 no.2
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• pp.130-134
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• 1988

Direct differential-pulse cathodic stripping voltammetry on mercury electrode (HMDE) provides a sensitive technique for low level cyanide measurement in distilled and sulfide free solution. Cyclic voltammetry revealed the forming and redissolution reactions were reversible at pH 7 in 0.1M KCl-0.01M phosphate supporting electrolyte. The analytical conditions have been optimized. With deposition time of 3 min at deposition potential 0.00V(vs. Ag/AgCl) in this medium of pH7, quite reproducible and linear calibration curve was obtained down to $3{\times}10^{-7}M$ (8ppb) $CN^-$ which was the detection limit.

• Journal of Environmental Science International
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• v.16 no.10
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• pp.1111-1118
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• 2007

A bismuth-coated carbon fiber microelectrode was prepared using cyclic voltammetry (CV). An analytical application was performed for the copper analysis with Square Wave Stripping Voltammetry (SWSV). Gallic acid n-propyl ester (PG) was used for the complex formation with a copper ion, and electrochemical measurements were performed with a pre-amplifier of a low-current module for nano am per detection. The effects of various parameters on the response were optimized. Analytical working ranges of $0.03-25.9\;{\mu}gl^{-1}$ and $0-25\'mgl^{-1}$ Cu(II) were obtained. The relative standard deviation at $13\;mgl^{-1}$ Cu was 0.9% (n = 12) in optimum conditions. The detection limit was found to have been $0.019\;{\mu}gl^{-1}$, with a 30-sec accumulation time. The developed methods were applied to a copper assay in water samples.

• Journal of the Korean Electrochemical Society
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• v.7 no.1
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• pp.9-15
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• 2004

Cyclic voltammetry and chronocoulometry have been used for characterization of catechol violet (CV) at the hanging mercury drop electrode in acetic acid-sodium acetate buffer solution. At pH 2.94 a nearly symmetric cyclic voltammetric wave due to an irreversible weak adsorption of CV on mercury was obtained at concentration of $0.53{\mu}mol\;dm ^{-3}$. Under these conditions, CV adsorbes in a monolayer. Upon increasing the concentration, the symmetry of the wave decreases; it can be attributed to a mixed diffusion adsorption process. The amount of the adsorbed catechol violet on the HMDE expressed as surface concentration as well as the surface areaf occupied by one molecule$(\sigma)$ were calculated. It was found that the values obtained for f and o utilizing cyclic voltammetric and chrono-coulometry are almost identical. A 1:1 and 1:2 Th (IV)-CV complexes are formed on addition of thorium (IV) to catechol violet. These complexes are adsorbed and reduced on the HMDE at more negative potentials than the peak potential of free CV, Using the square-wave (SW) technique, the adsorptive cathodic stripping voltammetry, ACSV, of these complexes was studied. It was found that the SW-ACSV of Th(IV)-CV can be applied to the determination of thorium at the nanomole level. Optimum conditions and the analytical method of determination were presented and discussed.

• Journal of Electrochemical Science and Technology
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• v.9 no.4
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• pp.276-281
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• 2018

High concentration of copper in mezcal, a representative Mexican spirituous alcoholic beverage, is a serious problem due to the damage that it may cause to human health. A cyclic voltammetry and square wave anodic stripping voltammetry study of copper (II) in three commercial mezcal samples based on glassy carbon electrode response was undertaken. The analysis was developed using a simulated matrix solution ($EtOH/H_2O$ (1:1), 0.1 M $LiClO_4$ and AcOH/AcONa 0.05 M/0.008 M), with Cu (II) concentrations in the range 0 - 1 ppm. Direct electrochemical analysis of mezcal samples was complicated by the presence of different organic compounds in the matrix. The analytical signal of Cu (II) in the spirituous was notably improved and the interferences caused by organic compounds were minimized, by diluting the mezcal samples 10% with $EtOH/H_2O$ (1:1) solution. An efficient quantification of Cu (II) was obtained from the calibration curve by the SWASV and using the internal standard method (Cd (II)) in commercial samples (1.2-6.7 ppm); the results were correlated satisfactorily with the values obtained by AAS.