• Korean Journal of Optics and Photonics
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• v.17 no.3
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• pp.290-295
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• 2006

The coupling between copper wire and a THz electromagnetic wave is one of the important factors to build up the magnitude and spectrum of a THz wave. We measured a I THz spectrum range THz pulse into a $480{\mu}m$ diameter and 23cm long copper wire waveguide. We measured THz pulses up to $275{\mu}m$ air gap between the end of the copper wire and transmitter or receiver chips. The coupling sensitivity of the transmitter is 3 times bigger than that of the receiver. The THz pulses propagated to air by the end of the receiver-side copper wire tip acting as a transmitter antenna. We confirmed that the THz field concentrates near the copper wire surface by opening the pin hole to the copper wire waveguide.

• Clean Technology
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• v.18 no.2
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• pp.183-190
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• 2012

Electrochemical regeneration of the iron chloride waste solution from PCB etching reduces environmental contamination and produces copper as by-product, so the economic feasibility is high. But iron chloride waste solution contains iron and copper and the reactions occurring in the electrolytic cell are complicated. In this work, the oxidation of iron chloride and copper deposition were examined through batch electrolysis and the optimum conditions of the process parameters were found. The oxidation of ferrous chloride was achieved easily to the desired level. The copper deposition efficiency was high in the reaction using the carbon cathode when the copper density was 12 g/L with the electric current density of $350mA/cm^2$, and the ratio of the $Fe^{2+}$ ion was high. In addition, the possibility of the scale-up was confirmed in continuous operation of bench reactor using the optimum conditions obtained.

• Transactions of Materials Processing
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• v.27 no.1
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• pp.37-47
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• 2018

In this paper, a double spot welding process, utilizing electric resistance heating dies, is suggested for the spot welding of dissimilar metal plates for drawing and concurrent spot welding. This double welding process has two heating methods for the fusion welding at the interfacial zone between steel and aluminum plates, such as heating method by thermal conduction of electric resistance by welding current induced to heating dies, and heating method by electric resistance between contacted surfaces of two plates by welding current induced to copper electrode. This double welding process has welding variables such as each current induced in heating dies and in copper electrode, outer diameters of heating dies, and edge shape of copper electrode. Experiments for current conditions in welding process should be demanded in order to get successful welding strength. It was known that the welding strength could be reached to the value demanded on industry fields under such welding conditions as heating dies of outer ring dia.12mm contacted on steel plate, as heating dies of outer ring dia. 14mm contacted on aluminum plate, and as copper electrode of dia. 6.0mm, and as 3 times continuous heating method by $1^{st}$ current of 11 kA(9cycle), $2^{nd}$ current 11 kA(60cycle), $3^{rd}$ current 7 kA(60cycle) applied in steel heating dies and copper electrodes, flat edge of copper electrode, for double spot welding process of dissimilar metal plates of steel and aluminum of 1.0 mm thickness.

• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.562-566
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• 2008

Reaction of AgNO3 with triethanolaminetriisonicotinate (L) produces 1 D coordination polymer of [Ag3(L)2](NO3)3 and the same treatment of Cu(NO3)2 with L gives 1D coordination polymer of [Cu(L)2](NO3)2. The nonrigid triethanolaminetriisonicotinate acts as a m 3-bridged tridentate for [Ag3(L)2](NO3)3 and a m 2-bridged bidentate for [Cu(L)2](NO3)2 to produce unusual motifs. The NO3- anions can be smoothly exchanged by PF6- anions in an aqueous suspension without destruction of the skeletal structure.

• Korean Journal of Crystallography
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• v.11 no.3
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• pp.147-150
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• 2000

The complex [CuL}Cl₂·3H₂O(1)(L=2,13-bis(2-hydroxyethyl)-5,16-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0/sup 1.18/,0/sup 7.12/] docosane) has been synthesized and characterized by X-ray crystallography. 1. crystallized in the monoclinic, space group C2/c, with a=21.647(6)Å, b=8.549(1)Å, c=18.132(5)Å, β=118.58(2)°, V=2946.8(12)ų, Z=4, R₁(wR₂) for 2374observed reflections of [I>2σ(I)] was 0.052(0.187). The centrosymmetric complex 1 has an axially elongated octahedral geometry with four secondary and tertially amines of the macrocycle and tow oxygen atoms of the pendant hydroxyethyl groups.

• Bulletin of the Korean Chemical Society
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• v.29 no.2
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• pp.499-502
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• 2008

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1006-1008
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• 2000

In this material, a traction motor for light railway vehicle was developed. Aluminium -Diecasting process was selected in order to reduce the manufacturing cost of making rotor bars and rotor rings of the motor, instead of copper or copper alloy rotor bars and rotor rings. And the results of experiment satisfied the international standard IEC 349-2.

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.961-964
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• 2009

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.9
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• pp.780-786
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• 2007

This paper describes the influence on partial discharge characteristics of defects at the model XLPE/EPDM interfaces of power cable joints. The defects of void and copper which could inadvertently be present at the joint interface. We measured ${\Phi}-n,\;{\Phi}-q$ patterns by a computer-aided partial discharge measuring system. Several parameters i, e, maximum discharge $q_{max}$ [pC], average discharge q [pC/cycle], and average angle of discharge ${\Theta}g$ [deg] were found to depend upon the defect type varying applied voltage. As the result of time evaluation, partial discharges are small different at copper defects, but is decreasing obviously about 20 minutes at void defect. It considered that difference of magnitude of total positive discharge of Q+ [pC] and total negative discharge of Q- [pC] is SPMD(swarming pulsive micro discharges).

• Electrical & Electronic Materials
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• v.10 no.5
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• pp.419-424
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• 1997

It is well known that the metallo-phthalocyanines (MPcs) are sensitive to toxic gaseous molecules such as NO$_2$ as well as are chemically and thermally stable. Therefore, lots of MPcs have been studied as the potential chemical sensor for NO$_2$gas using quartz crystal microbalance(QCM) or electrical conductivity. In this study, thin films of octa(2-ethylhexyloxy)copper-phthalocyanine were prepared by Langmuir-Blodgett method and characterized by using UV-VIS absorption spectroscopy and ellipsometry. Optimal transfer condition of LB films was investigated and preliminary results of current-voltage(I-V) characteristics of these films exposed to NO$_2$gas as a function of film thickness, temperature and concentration were discussed.