• 제목/요약/키워드: Mercury electrode

검색결과 98건 처리시간 0.024초

Real-time Voltammetric Assay of Cadmium Ions in Plant Tissue and Fish Brain Core

  • Ly, Suw-Young
    • Bulletin of the Korean Chemical Society
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    • 제27권10호
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    • pp.1613-1617
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    • 2006
  • Optimum analytical conditions for cyclic voltammetry (CV) and square wave (SW) stripping voltammetry were determined using mercury-mixed carbon nanotube paste electrode (PE). The results approached the microgram working ranges of SW: 10.0-80.0 $ugL^{-1}$ and CV: 100-700 $ugL^{-1}$ Cd (II); working conditions of 300-Hz frequency, 100 mV amplitude, 1.6 V accumulation potential, 400 sec accumulation time, and 40 mV increment potential. First, analysis was performed through direct assay of cadmium ions deep into the fishs brain core and plant tissue in real time with a preconcentration time of 400 sec. The relative standard deviation of 10.0 $mgL^{-1}$ Cd (II) observed was 0.064 (n = 12) at optimum conditions. The low detection limit (S/N) was set at 0.6 $ugL^{-1}$ ($5.33{\times}10^{-9}$ M). The methods can be used in direct analysis in vivo or in real-time monitoring of plant tissue.

The Study of the Electroconductive Liquids Flow in a Conduction Magnetohydrodynamic Pump

  • Naceur, Sonia;Kadid, Fatima Zohra;Abdessemed, Rachid
    • Transactions on Electrical and Electronic Materials
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    • 제17권5호
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    • pp.252-256
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    • 2016
  • This paper deals the study of a linear MHD pump solution used to eliminate and to avoid the dangers of the mercury appearing through pollution and contamination. The formulation of the magnetohydrodynamic phenomena is derived from Maxwell and Navier-Stokes equations are solved using the finite volume method. Simulation results highlight the performance of the pump such as the electromagnetic force, the velocity, and the pressure, the application of Ansys-Fluent software validation these results.

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

  • 최원형;이진식;김재수;김도훈
    • 분석과학
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    • 제5권1호
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    • pp.7-15
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    • 1992
  • 게르마늄을 Phenylfluorone과 착물을 만들어 과염소산 지지전해질에서 Linear Sweep Voltammetry에 의해 정량하고, 염산용액 중에서 형성된 착물을 UV-VIS Spectrophotometry로 정량한 결과를 비교하였다. 이때 전기화학적인 방법의 경우 정량범위가 $2.5{\sim}80{\mu}g/L$이었고, 분광광도법의 경우는 $10{\sim}300{\mu}g/L$이었다.

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Anodic Stripping Polarograph에 의한 극미량 게르마늄의 분석(II) (Determination of Trace Germanium by Anodic Stripping Polarography)

  • 최원형;이종무
    • 분석과학
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    • 제5권1호
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    • pp.17-24
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    • 1992
  • Catechol의 유도체인 3, 4-dihydroxybenzoic acid, 3, 4-dihydroxybenzaldehyde, 그리고 adrenaline을 사용하여 게르마늄과 착물을 형성시킨 후 Anodic Stripping Polarography로 정량한 후, 천연물 중의 게르마늄 정량에 적용시켜 분석한 결과 인삼에서 $300{\mu}g/L$, 광천수에서 $210{\mu}g/L$를 검출할 수 있었다.

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ICP 제논 램프의 가스 압력과 공급 전력에 따른 광학적 특성연구 (The study of optical properties by gas pressure and applied power in ICP Xe lamp)

  • 최기승;이종찬;최용성;박대희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.119-121
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    • 2005
  • The problem of lamp life have being solved before electrode-less lamps were developed. But, mercury is using till now. So people are concerned about friendly-environmental lamp, and many researcher hardly study it. In this paper, an ICP lamp which is using Xe gas and Ne gas was designed after optical properties were measured and analyzed. As a result, H-mode properties and penning effect properties were known. Also xenon and neon of properties analyze by spectrum.

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Polarography에 依한 Titanium Oxalato 및 Oxalatous Complex에 關한 硏究 (Polarographic Study of Titanium Oxalato and Oxalatous Complex)

  • 김황암;한동진
    • 대한화학회지
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    • 제9권2호
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    • pp.71-74
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    • 1965
  • Reduction of Ti(Ⅳ)-oxalate complex on dropping mercury electrode has been studied as a function of oxalate concentration and of pH varied with HCl. Assuming there are equilibrium $TiO(C_2O_4)_2= \;+\;2H^+\;=\;Ti^{+4}\;+\;2C_2O_4\;=\;+\;H_2O,\;K_4$ in addition to $TiO(C_2O_4)_2\;^=\;=\;TiO^{++}\;+\;2C_2O_4=\;K_2\;Ti(C_2O_4)_2\;^-\;=\;Ti^{+3}\;+\;2C_2O_4=\;K_3$ in the system cathodic wave has been well explained for that pH is higher than 0.5. The equilibrium constants $K_2,\;K_3$ and $K_4$ have been to be $2{\times}10^{-12},\;5{\times}10^{-13}$ and $10^{-11}$, respectively. The reduction of Ti(Ⅳ)-oxalate system is $Ti^{+4}\;+\;e\;{\to}\;Ti^{+3}$ in the concentration of hydrochloric acid, higher than 3M.

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펄스차이 흡착법김전압전류법에 의한 갈륨 정량 (Determination of Gallium by differential Pulse Adsorptive Stripping Voltammetry)

  • 손세철;엄태윤
    • 대한화학회지
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    • 제36권6호
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    • pp.889-893
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    • 1992
  • Ga-Morin 착물에 대한 흡착벗김전압전류법적 연구를 HMDE를 사용하여 0.1M 아세테이트 완충용액에서 연구하였다. HMDE의 수은 표면에 흡착된 착물의 환원피크 전류에 미치는 여러 분석조건들의 영향을 논의하였으며, 여러 양이온 및 계면활성제의 방해효과에 대하여 검토하였다. 본 연구에서의 검출한계는 흡착시간이 60초일 때 1.7nM 이었으며, 4 ${\mu}$g/l의 Ga를 7회 분석하였을 때 상대표준편차 2.8% 이었다.

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아크튜브내의 구성물 손실이 세라믹 메탈 핼라이드 램프의 특성에 미치는 영향분석 (Analysis of the Effect on the Performance of Ceramic Metal Halide Lamp by the Loss of Elements that have been Filled in Arc Tube)

  • 장혁진;양종경;박대희
    • 전기학회논문지
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    • 제58권12호
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    • pp.2446-2452
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    • 2009
  • A Ceramic Metal-halide lamp is achieved by adding multiple metals to a basic mercury discharge. Because the vapor pressure of most metals is very much lower than mercury itself, metal-halide salts of the desired metals, having higher vapor pressures, are used to introduce the material into the basic discharge. The metal compounds are usually polyatomic iodides, which vaporize and subsequently dissociate as they diffuse into the bulk plasma. Metals with multiple visible transitions are necessary to achieve high photometric efficiency and good color. Compounds of Sc, Dy, Ho, Tm, Ce, Pr, Yb and Nd are commonly used. The maximum visible efficacy of a Ceramic Metal Halide lamp, under the constant of a white light source, is predicted to be about 450lm/W. This is controlled principally by the chemical fill chosen for a particular lamp. Current these lamps achieve 130lm/W and these life time are the maximum 16,000[hr]. So factors of performance lower are necessary to improve lamp performance. In this paper, we analyzed factors of performance lower by accelerated deterioration test. The lamp was operated with short duration turn-on/turn-off procedure to enhance the effect due to electrode sputtering during lamp ignition. The tested lamp that was operated with a longer turn-on/off(20/20 minutes) showed blackening, changed distance between electrodes and lowered color rendering & color temperature by losses of Dy at 421.18nm, I at 511nm, T1 at 535nm and Na at 588nm compared with the new lamp.

제논 혼합가스를 이용한 고효율 면광원과 국부적 밝기 제어 방식 (High Luminous Efficiency Flat Light Source with Xe mixture Gas Discharge and Areal Brightness Control Method)

  • 정재철;서인우;오병주;황기웅
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2009년도 추계학술대회 논문집
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    • pp.153-157
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    • 2009
  • A Highly efficient Mercury-free Flat Fluorescent Lamp (MFFL) with dielectric barrier Xe gas discharge was developed for an alternative of conventional line-type Cold Cathode Fluorescent Lamps (CCFLs) which shows a wide voltage margin and a stable discharge operation for diffuse glow discharge with an application of a auxiliary electrode. Electro-optic characteristics of the MFFL were examined through the changes in ambient temperature, total pressure and Xe partial pressure. the single cell is expanded into a multi-structured configuration to realize a large sized lamp by a simple repetition of the single cells, and a new driving scheme is proposed for an adaptive brightness control using dual auxiliary electrodes and bi-polar drive scheme. In addition, interesting application of this ultra high luminance flat lamp by the optimization of the gas condition and the pattern of the rear phosphor layer is suggested as a good alternative of daylight lamp source

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무수은 면광원 램프용 Scanning Backlight 구동회로 (Scanning backlight Driver for Mercury free flat fluorescent lamp)

  • 오은태;정용민;이경인;유호원;이준영
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2008년도 하계학술대회 논문집
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    • pp.553-555
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    • 2008
  • 현재 사용하고 있는 LCD(Liquid Crystal Display) Backlight용 램프는 주로 CCFL(Cold Cathod Fluorescent Lamp)과 EEFL(External Electrode Fluorescent Lamp)이 사용되고 있다. 하지만 이 램프는 수은을 사용하여 RoHS(the Restriction of the use of certain Hazardous Substances in electrical and electronic equipment)규제가 점점 강화되면서 사용이 제한되고 있으며, 이에 따라 수은을 사용하지 않는 램프의 제작이 불가피해지고 있다. 또한 LCD TV는 CRT와 PDP와는 다른 LCD만의 Hold-type 특성과 LC(Liquid Crystal)의 응답속도로 인하여 Motion Blur현상이 나타나는 단점이 있다. 본 논문에서는 RoHS 규제를 만족시키는 무수은 면광원 램프를 구동하기 위한 인버터를 제안한다. 제안한 인버터는 포워드 방식을 사용하여 반도체 소자 및 자기 소자의 수를 줄여서 구동회로가 간단하다. 또한 면광원 램프를 세로방향으로 6블록으로 나누어 스캔구동을 하여 Motion Blur현상을 저감 시켰다. 끝으로 실험을 통하여 제안한 인버터의 유용성을 입증하였다.

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