• 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.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.620-625
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• 2011

A simple, rapid potentiometric back titration of Isoniazid (INH) in the presence of Rifampicin (RIF) in tablets and syrups is described. The method is based on the oxidation of INH by a known excess of copper (II) ion and the back titration of unreacted copper (II) ion potentiometrically with ascorbic acid using a lab-made Copper Based Mercury Film Electrode (CBMFE). The titration conditions have been optimized for the determination of 1.0-10.0 mg of INH in pure and dosage forms. The precision and accuracy of the method have been assessed by the application of lack-of-fit test and other statistical methods. Interference was not caused by RIF and other excipients present in dosage forms. Application of the method for INH assay in tablets and syrups was validated by comparison of the results of proposed method with that of the British Pharmacopoeia (BP) method using F- and t- statistical tests of significance.

• Electric Engineers Magazine
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• v.263 no.7
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• pp.28-35
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• 2004

접지 시스템의 계획은 접지전극 형상의 설계와 계통접지 방식에 따른 접지 시스템으로 구성하여야 하고 접지 또는 금속체간에 전위차가 발생하지 않도록 Bonding, 기술을 충분히 고려하여야 한다.<중략>

• 한국전기화학회:학술대회논문집
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• 1999.04a
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• pp.76-76
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• 1999

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.325-328
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• 2006

고분자 전해질 연료전지의 전극을 gradient catalyst coating 방법을 이용하여 제조하였다. 촉매 잉크제조 시 나피온 이오노머의 함침 구성비를 다르게 하여 조성 비율이 다른 gradient 구조를 갖도록 하여 전극을 제조하였다. Anode Cathode의 두 전극을 각각 나피온 함량비가 다른 두 개의 gradient 층구조의 촉매층으로 9:1, 8:2, 7:3, 6:4 비율의 조성비로 성능을 측정하였으며, 전극의 전기화학적 반응 면적을 알아보기 위해 순위전위법을 그리고 분극 저항(Polarization resistance) 변화를 알아보기 위해서는 0.7V에서 임피던스 측정법의 전기화학분석법으로 전극 제조법에 따른 성능변화를 확인하였다. 특히 Gradient catalyst coating 방법을 이용하여 제조한 MEA는 종래 방식의 MEA보다 high current $density(1000mA/cm^2)$이상에서 향상된 성능을 보였다.

• Journal of the Korean Vacuum Society
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• v.21 no.6
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• pp.312-321
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• 2012

The electric potential of plasma column is measured with the high voltage probe in a pair of atmospheric plasma jets operated by AC-voltage. According to the polarity of voltage applied to the electrodes, the polarity of plasma column potential has the same polarity of applied voltage. The high potential of plasma column at the side of high voltage electrode is decreased linearly along the plasma column to the ground side. Therefore, the plasma column seams to be a kind of resistor whose resistivity is a few 10s $M{\Omega}/m$. In the experiment of double-jets system, the polarity of plasma potential is verified to be the same polarity to the applied voltage. When the different voltage polarities are applied to the electrodes of double plasma jets, the attractive force is acted between two plumes at the merged plasma and the plasma potential is measured to be low as a few 10s V. When the same polarity of voltage is applied to the electrode, the repulsive force is acted and the plasma potential is measured to be high as a several 100s V at the merged plumes. In the exposure of plasma plume on the bio-substrate with the double plasma jets, the electric shock and thermal damage might be proportional to the plasma power which is the multiplication of the plasma potential and the plasma current.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.4 no.4
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• pp.68-78
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• 1990

절연파괴의 원인이 되는 절연체중의 공간전하의 여러 특성을 정량적으로 측정하였다. 전극에서의 주입전하가 트랩되어 주로 공간전하를 형성하는 것을 확인하였다. TSSP측정법으로 컬렉팅 전위를 결정하고 바이어스의 시간, 전압, 온도에 따른 공간전하 변화량을 측정하여 공간적 분포의 깊이를 조사하였다. 그리고 정상상태에 있어서 모델과 해석과 시험 결과가 비교적 잘 일치함을 발견하였다.

• Magazine of the Korea Concrete Institute
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• v.4 no.2
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• pp.75-81
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• 1992

염분을 함유한 철근콘크리트중의 철근부식에 관한 2년 촉진시험으로부터 콘크리트표면에서 측정한 자연전위값과 실제의 철근 부식상황과를 비교한 결과 철근의 수식상황을 자연전위법을 이용하여 비파괴적으로 진단하는 방법이 유효함을 알았다. 포화칼로멜전극을 사용했을 경우 -300mV이하이면 부식이 발생하였으며 -200mV이상이면 부식이 발생하지 않았다. 또한 부시공시체에 대한 휨강도시험도 행하였으며 중성화에 대한 검토로 행하였다.

• Applied Chemistry for Engineering
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• v.32 no.4
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• pp.456-460
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• 2021

A potentiometric sodium-ion (Na⁺) sensor was prepared using a screen-printing process with carbon and silver inks. The two-electrode configuration of the sensor resulted in potential differences in Na⁺ solutions according to Nernstian equation. The obtained Na⁺-sensor exhibited an ideal Nernstian sensitivity, fast response time, and low limit of detection. The Nernstian response was stable when the sensor was tested for repeatability and long-term durability. The Na⁺-selective membrane coated onto the carbon electrode selectively passed sodium ions against interfering ions, indicating an excellent selectivity. The portable Na⁺-sensor was finally fabricated using a printed circuit system, demonstrating the successful measurements of Na⁺ concentrations in various real samples.

• Journal of the Korean Chemical Society
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• v.37 no.8
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• pp.723-729
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• 1993

Cu(II) ion-responsive chemically modifed electrodes (CMEs) were constructed by incorporating 1-(2-pyridylazo)-2-naphthol (PAN) into a conventional carbon-paste mixture of graphite powder and Nujol oil. Cu(II) ion was chemically deposited on the surface of the PAN-chemically modified electrode in the absence of an applied potential by immersion of the electrode in a buffer solution (pH 3.2) containing Cu(II) ion, and then reduced at a constant potential in 0.1 M KNO$_3$. And a well-defined voltammetric peak could be obtained by scanning the potential to the positive direction. The electrode surface could be regenerated with exposure to acid solution and reused for the determination of Cu(II) ion. In 5 deposition / measurement / regeneration cycles, the response could be reproduced with 6.1${\%}$ relative standard deviation. In case of using the differential pulse voltammetry, the calibration curve for Cu(II) was linear over the range of 2.0 ${times}$ 10$^{-7}$ ∼ 1.0 ${times}$ 10$^{-6}$ M. And the detection limit was 6.0 ${times}$ 10$^{-8}$ M. Studies of the effect of diverse ions showed that Co, Ni, Zn, Pb, Mg and Ag ions added 10 times more than Cu(II) ion did not influence on the determination of Cu(II) ion, except EDTA and oxalate ions.