• Title/Summary/Keyword: LSV

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A Novel Sensor Based on Electropolymerization Poly(safranine) Film Electrode for Voltammetric Determination of 4-Nitrophenol

  • Liu, Xing-Yuan
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1182-1186
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    • 2010
  • A novel poly(safranine)-modified electrode has been constructed for the determination of 4-nitrophenol (4-NP) in natural water sample. The electrochemical behavior of poly(safranine) film electrode and its electrocatalytic activity toward 4-NP were studied in detail by cyclic voltammetry (CV) and adsorptive linear stripping voltammetry (LSV). All experimental parameters were optimized and LSV was proposed for its determination. In optimal working conditions, the reduction current of 4-NP at this poly(safranine)-modified electrode exhibited a good linear relationship with 4-NP concentration in the range of $8.0{\times}10^{-8}$ to $4.0{\times}10^{-5}mol\;L^{-1}$. The detection limit was $3.0{\times}10^{-8}mol\;L^{-1}$. The high sensitivity and selectivity of the sensor were demonstrated by its practical application for the determination of trace amounts of 4-NP in natural water and fruit samples.

The Determination of Germanium(IV) by Linear Sweep Voltammetry and UV-VIS Spectrophotometry (Linear Sweep Voltammetry와 UV-VIS Spectrophotometry를 이용한 게르마늄 분석)

  • Choi, Won-Hyung;Lee, Jin-Sik;Kim, Jae-Soo;Kim, Do-Hun
    • Analytical Science and Technology
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    • v.5 no.1
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    • pp.7-15
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    • 1992
  • Germainium(IV) was determined in perchloate supporting electrolyte solution containing phenylfluorone by hanging mercury drop electrode(HMDE) of Linear Sweep Voltammetry(LSV) and in hydrochloric acid solution by UV-VIS Spectrophotometry. The complex germanium(IV) with phenylfluorone was shown linear calibration curve in the range of $2.5{\sim}80{\mu}g/L$ by LSV and in the range of $10{\sim}300{\mu}g/L$ by UV-VIS Spectrophotometry.

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A Study on the Electrochemical Mechanism using Liner Sweep Voltammetry (LSV) Method (LSV법을 이용한 전기화학적 메커니즘 연구)

  • Lee, Young-Kyun;Han, Sang-Jun;Seo, Yong-Jin;Lee, Woo-Sun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.164-164
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    • 2008
  • 금속배선공정에서 높은 전도율과 재료의 값이 싸다는 이유로 최근 Cu를 사용하였으나, 디바이스의 구조적 특성을 유지하기 위해 높은 압력으로 인한 새로운 다공성 막(low-k)의 파괴와, 디싱과 에로젼 현상으로 인한 문제점이 발생하게 되었다. 이러한 문제점을 해결하고자, 본 논문에서는 Cu 표면에 Passivation layer를 형성 및 제거하는 개념으로 공정시 연마제를 사용하지 않으며, 낮은 압력조건에서 공정을 수행하기 위해, 전해질의 농도 변화에 따른 Liner sweep voltammetry 법을 사용하여 전압활성화에 의한 전기화학적 반응이 Cu전극에 어떤 영향을 미치는지 연구하였으며, 표면 조성을 알아보기 위하여 Energy Dispersive Spectroscopy (EDS) 분석을 하였고, Cu disk의 결정성과 배향성 관찰을 위해 X-Ray diffraction (XRD)로 금속 표면을 비교하여 실험 결과로 얻어진 데이터를 통하여 ECMP 공정에 적합한 전해액 선정과 농도를 선택하였다.

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Case Drop and Prosodic Structure in Korean

  • Hong, Sung-Hoon
    • Speech Sciences
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    • v.7 no.3
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    • pp.35-51
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    • 2000
  • The goal of this paper is to examine how Case Drop (the drop of the case markers) correlates with the prosodic structure in Korean. On the assumption that intervocalic Lenis Stop Voicing (LSV) applies within the domain of the Accentual Phrase (AP), voicing analyses are performed on intervocalic lenis stop consonants before and after Case Drop. A statistical analysis reveals that the drop of the nominative and accusative case markers significantly alter the AP structure. Pitch values will then be extracted to verify that such changes in the AP structure conform to the pitch properties proposed for the AP (Jun 1993, 1998). The results show that the AP structure suggested by LSV does not always coincide with that imposed by the pitch properties.

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침투법(infiltration)을 이용한 고체 산화물 연료전지용 복합체 전극 제조 및 평가

  • Park, Jong-Seong;Vohs, J.M.;Gorte, R.J.
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.57.2-57.2
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    • 2012
  • 산소 이온 전도성 세라믹을 이용한 고체 산화물 연료전지의 전극은 원활한 전기화학반응을 위해, 이온 전도도, 전자 전도도 및 전기화학적 활성을 동시에 가지고 있어야 한다. 이를 위해 복합체 전극을 사용하며, 특히 음극의 경우 니켈(Nickel)과 Yttria-stabilized zirconia (YSZ)로 이루어진 복합체 전극을 혼합 및 소결을 통해 제조하여 사용하였다. 하지만, 니켈의 경우 탄화 수소 연료에서의 탄소 침적 문제와 열악한 산화환원 안정성(redox stability)등의 문제점을 가지고 있다. 따라서 니켈대신 전도성 세라믹을 사용한 세라믹 복합체 음극 개발이 활발히 이루어지고 있으며, 그 중 침투법(infiltration method)을 이용한 복합체 전극 제조 방법을 소개한다. 실제로 니켈 금속과 유사한 높은 전기 전도도를 갖는 Sr-doped Lanthanum Vanadate (LSV)을 이용해, YSZ-LSV 복합체 전극을 침투법을 이용해 제조하고, 소량의 촉매을 첨가하여, 이온전도도, 전자 전도도 및 촉매 활성을 갖는 복합체 음극을 제조하였다. 이 복합체 음극의 탄화수소에서의 연료전지 성능 및 redox stability을 측정하였다.

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Effect of copper surface to $HNO_3$ electrolyte ($HNO_3$ 전해액이 Cu 표면에 미치는 영향)

  • Park, Sung-Woo;Han, Sang-Jun;Lee, Young-Kyun;Lee, Woo-Sun;Seo, Yong-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.123-123
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    • 2008
  • 본 논문에서는 Cu의 ECMP 적용을 위해 $HNO_3$ 전해액의 active, passive, transient, trans-passive 영역을 I-V 특성 곡선을 통해 알아보았고, LSV (Linear sweep voltammetry)와 CV (Cyclic voltammetry)법을 통하여 전기화학적 특성을 비교 분석하였다.

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Characteristics of Voltammetric Urea Sensors Based on Poly(3-methylthiophene) film (Poly(3-methylthiophene)막 위에 urease를 고정화 한 voltammetric biosensor의 특성)

  • Park, Sung-Ho;Park, Buh-Hun;Min, Nam-Ki;Hong, Suk-In
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1766-1768
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    • 2000
  • 신장병 진단의 척도로 요소의 농도는 매우 중요하다. 요소의 농도를 측정하기 위한 센서개발이 본 연구의 목적이다. 기존의 Potentiometry법은 Nernst식이 적용된다는 가정하에 감도를 측정했다. 실험결과 전극상에서 우레아제의 요소 가수분해 반응은 Nernst식을 적용할 수 없는 비가역적인 반응으로 판단되어 센서의 감도 측정을 Linear sweep Voltammetry(LSV)법을 이용하였다. Voltammetry법은 가역적이든 비가역적이든 관계없이 Cottrell 식에 의한 전류와 농도의 직선관계로부터 감도를 측정할 수 있다는 장점이 있다. 센서 전극의 표면은 SEM으로 분석하였고, LSV 법으로 측정한 센서의 감도는 $34{\mu}A$/decade 였다.

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Molecular Analysis of the 3'-Terminal Region of Lily Latent Carlavirus from Lilium lancitoium

  • Ryu, Ji-Hwan;Park, Hye-Won;Park, Won-Mok;Lee, Se-Yong;Ryu, Ki-Hyun
    • The Plant Pathology Journal
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    • v.16 no.4
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    • pp.231-235
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    • 2000
  • The 3,000 nucleotides of 3'-terminal region of the genomic RNA of a new isolate of carlavirus from a Korean native lily (Lilum lancitoium) was cloned and its nucleotide sequences were determined. The coat protein (CP) gene of the virus showed 72.0% to 72.8% nucleotide sequence identities and 86.9% to 88.0% amino acid sequence identities with those of the four strains (two Korean, one Dutch, and one Japanese isolates) of lily symptomless virus (LSV). Interestingly, different amino acid sequences between the new isolate and LSV strains were located at the N-terminal region of the CP. Pairwise amino acid sequence comparison of the CP gene revealed sequence identities of 22.0% to 71.1% between the virus and other 9 carlavirus species. The 25 kDa and 12 kDa proteins genes of the virus share 30.7% to 76.3% and 31.1% to 85.8% amino acid sequence identities, respectively, with those of 8 other carlaviruses. The 16 kDa protein gene of the virus shares 16.7% to 72.9% amino acid sequence identities with that of 9 other carlaviruses. These data indicate that the virus, designated as lily latent virus (LiLV), is a distinct of the Carlavirus genus and distinguished from the known strains of LSV.

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Effect of copper surface to $HNO_3$ and $KNO_3$ electrolyte ($KNO_3$$HNO_3$ 전해액이 Cu에 미치는 영향)

  • Seo, Yong-Jin;Han, Sang-Jun;Park, Sung-Woo;Lee, Young-Kyun;Lee, Sung-Il
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.486-486
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    • 2009
  • In this paper, the current-voltage (I-V) curves, such as linear sweep voltammetry (LSV) and cyclic voltammetry (CV), were employed to evaluate the effect of electrolyte concentration on the electrochemical reaction trend. From the I-V curve, the electrochemical states of active, passive, transient and trans-passive could be characterized. And then, we investigated that how this chemical affect the process of voltage-induced material removal in electrochemical mechanical polishing (ECMP) of Copper. The scanning electron microscopy (SEM) and energy dispersive spectroscopy EDS) analyses were used to observe the surface profile. Finally, we monitored the oxidation and reduction process of the Cu surface by the repetition of anodic and cathodic potential from cyclic voltammetry (CV) method in acid- and alkali-based electrolyte. From these analyses, it was important to understand the electrochemical mechanisms of the ECMP technology.

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