• Journal of the Korean Chemical Society
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• v.37 no.12
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• pp.1053-1059
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• 1993

The determination of iron(Ⅱ), iron(Ⅲ) and total iron was studied by differential-pulse and Tast polarography in 0.1 M acetate buffer solution at pH 4.60, Half wave potentials of iron(Ⅱ)-DTPA and iron(Ⅲ)-DTPA complexes were -0.150V vs. SCE reference electrode. In the presence of DTPA the redox process of iron(Ⅱ) and iron(Ⅲ) was reversible. Linear calibration plots were obtained for iron(Ⅱ) and iron(Ⅲ) concentration of 0.2∼1.0 mM. The detection limits of iron(Ⅱ) and iron(Ⅲ)by Tast polarographic method were 0.05 mM and 0.07 mM, respectively.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.56 no.2
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• pp.109-114
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• 2007

This paper summarize about the auxiliary electrode measured a ground resistance. The method to measure a ground resistance is the fall-of-potential method to using an auxiliary electrode. And an auxiliary electrode must be set up on the ground. Today it is so difficult to set up the auxiliary electrode on the ground because of many concrete building and many paved roads. So this paper is regarding a trust analysis of the ground resistance measurement by the substitute auxiliary electrode. It substituted a iron structure around the building, a neutral line multiplex ground to earth, a wire net for auxiliary electrode. This information is confirmed bv compared with the measurement value.

• Bulletin of the Korean Chemical Society
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• v.15 no.7
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• pp.526-529
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• 1994

• Proceedings of the KIEE Conference
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• 2007.04b
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• pp.85-87
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• 2007

This paper summarize about the auxiliary electrode measured a ground resistance The method to measure a ground resistance is the fall-of-potential method to using an auxiliary electrode. And an auxiliary electrode must be set up on the ground. Today it is so difficult to set up the auxiliary electrode on the ground because of many concrete building and many paved roads. So this paper is regarding of the ground resistance measurement by the substitute auxiliary electrode. It substituted a iron structure around the building, a wire net for auxiliary electrode. This information is confirmed by compared with the measurement value.

• Analytical Science and Technology
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• v.20 no.4
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• pp.289-295
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• 2007

A simple electric circuit of an infrared photodiode electrode (IPDE) was utilized to monitor iron using square-wave (SW) anodic stripping voltammetry (SV) and cyclic voltammetry (CV). The optimum analytical conditions were determined and were compared with those of common working electrodes. The comparison showed that CV is more sensitive and convenient to use than the common voltammetry methods. At the optimized conditions, the working ranges of 0.1- to 0.8- and 0.85- to 6.0 mg/L iron was obtained. Relative standard deviation of 15 measurements of iron (0.4 mg/L) was 0.09%. The analytical detection limit was found to be $80{\pm}0.6ug/L$, which was applied to iron in waste water.

• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.308-311
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• 1998

Some nondestructive diagnostic methods including various types of corrosion sensors have been investigated. Under these conditions, a new structure of sensor that has a pair of electrode and magneto-supply was proposed. In order to detect the edge of the iron rust part, three-poles touch-type corrosion sensor is now proposed. The iron rust pattern where the sensor touches is estimated by means of the impedance of the sensor, and the edge of the iron rust is recognized by comparing the three measured impedances. As the result, our proposed sensor is useful to detect the initial state of iron rust.

• Journal of Environmental Science International
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• v.20 no.5
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• pp.623-630
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• 2011

This study investigated the degradation of N, N-Dimethyl-4-nitrosoaniline (RNO, indicator of the generation of OH radical) by using dielectric barrier discharge (DBD) plasma. The DBD plasma reactor of this study consisted of a quartz dielectric tube, titanium discharge (inner) and ground (outer) electrode. The effect of shape (rod, spring and pipe) of ground electrode, diameter (9~30 mm) of ground electrode of spring shape and inside diameter (4~13 mm) of quartz tube, electrode diameter (1~4 mm), electrode materials (SUS, Ti, iron, Cu and W), height difference of discharge and ground electrode (1~15.5 cm) and gas flow rate (1~7 L/min) were evaluated. The experimental results showed that shape of ground electrode and materials of ground and discharge electrode were not influenced the RNO degradation. The thinner the diameter of discharge and ground electrode, the higher RNO degradation rate observed. The effect of height gap of discharge between ground electrode on RNO degradation was not high within the experimented value. Among the experimented parameters, inside diameter of quartz tube and gas flow rate were most important parameters which are influenced the decomposition of RNO. Optimum inside diameter of quartz tube and gas flow rate were 7 mm and 4 L/min, respectively.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.11a
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• pp.283-287
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• 2004

Arc welding is sometimes used to repair damaged cast iron parts in diesel engine for driving a ship. In this case cola arc welding. is good for. saving the time and results in good repairing. But if some difference in hardness on welding zones made with AWS E Ni-CI and NiFe-CI. happen, repaired parts would be cracked in a short. In order to overcome this default, the study is performed on varying preheating temperature of welding parts, selecting welding rod and welding work way. The result will be used on ship's repair working shop.

• Journal of Ocean Engineering and Technology
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• v.20 no.2 s.69
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• pp.41-45
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• 2006

Arc welding is sometimes used to repair damaged cast iron parts in diesel engine for driving n ship. In this case cold arc welding is good for saving the time and results in good repairing. But if some difference in hardness on welding zones made with AWS E Ni-CI and NiFe-CI happen, repaired parts would be cracked in a short. In order to overcome this default, the study is performed on varying preheating temperature of welding parts, selecting welding rod and welding work way. The result will be used on ship's working shop.

• Journal of Welding and Joining
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• v.1 no.2
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• pp.1-6
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• 1983

용접중 발생되는 흄(Fume) 및 가스는 용접작업 환경을 오염시킬 뿐만 아니라 인체에 매우 유해하다. 용접 흄(Fume)은 금속 산화물로 구성된 아주 작은 입자이며 가스는 일반적으로 CO, CO$_{2}$, NO$_{x}$, SO$_{x}$, XF 등으로 구성되어 있다. 일반 피복 아아크 용접봉에서 발생되는 용접 흄은 인체에 매우 해로운 영향을 미친다. 즉 다량 흡입하게 되면 두통, 발열 등 급성 증상이 발생한다. 또한 소량을 장시간 흡입해도 진폐 등 만성증상을 일으킨다. 그러므로 현 국내 용접장에서는 흄에 의한 장해 방지를 위하여 충분한 환기시설과 완벽한 보호구 착용, 그리고, 용접 재료 자체의 흄 발생량을 감소시킨 저흄 용접봉(low fume type electrode)의 사용 방법 등이 검토 실시되고 있다. 본 보고서에서는 흄에 대한 올바른 인식을 꾀하는 한편, 용접자의 건강 보호를 목적으로 개발된 조선 및 철구조물의 주요 용접 재료인 철분 산화철계 저흄 용접봉에 관하여 소개하고자 한다.