• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.8
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• pp.539-543
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• 2015

At present, the development of a detection device in order to prevent accidents due to wire deterioration in the distribution lines is required. Distribution line is not possible to check the internal state in a normal way because it is covered with the coating. Accordingly, various eddy current techniques that is the non-destructive test (NDT) techniques have been applied to solve this problem. In this paper, we have seen examining the characteristic change of the eddy current sensor according to the simplified shape of the sensor in order to solve the problems for the simplified shape that is generated when the simulation for the shape of the eddy current sensor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.288-291
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• 2001

It is very important to select suspension solution for forming electrophoretic deposited YBCO thick mm, because it is heavily affected to its superconducting properties. In this paper, high-temperature superconductor films of $YBa_{2}Cu_{3}O_{7-x}$ were fabricated by electrophoretic deposition (EPD) from alcohol-based suspension such as iso-propanol, iso-butanol, and their mixture. For the formation of YBCO dense and adherent coating on a silver wire by EPD, 1 % PEG(1000) 2 ml, as a additive for making their surface crack-free, was used for electrophoresis. As a results, the cracks were considerably decreased and the superconducting critical current density $(J_e)$ without/with PEG was $1200A/cm^2$ and $2020A/cm^2$, which films deposited in mix iso-propanol and iso-butanol suspension.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.317-317
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• 2010

ZnO나노와이어는 높은 투과도, 화학 및 열적 안정성을 가지며, 유기태양전지에 적용하였을 때 Active Layer의 표면적 증가, 전자의 수집 및 전달에 용이한 장점가지고 있어 하이브리드 유기 태양전지에 적용되고 있다. ZnO나노와이어와 P3HT/PCBM을 사용한 하이브리드 유기태양전지는 Active Layer의 열처리 온도를 변화시켜 ITO/AZO/ZnO wire/PCBM:P3HT/PEDOT:PSS/Ag구조로 제작되었다. ZnO나노와이어는 AZO를 Seed로 사용하고 Znc nitrate hydrate와 hexamethylenetetramine을 혼합하여 수열합성법으로 성장 후, P3HT:PCBM, PEDOT:PSS을 Spin Coating법으로 형성하였다. UV-vis와 Solar simulator를 통하여 Active Layer의 열처리 온도에 따른 태양전지의 특성을 분석하였다.

• Transactions of Materials Processing
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• v.17 no.2
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• pp.91-96
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• 2008

The governing parameters affecting the fatigue properties have been investigated experimentally in the high carbon steel wires with 0.94 wt.%C. In order to find the crucial factors, the advanced analysis techniques such as optical 3-D profiler, focused ion beam(FIB) and transmission electron microscope(TEM) were used. The two-type steel wires with different drawing strain were fabricated. The fatigue properties were measured by hunter rotating beam tester, specially designed for thin-sized steel wires. It was found that the fatigue properties of the steel wires with high drawing strain was higher than that with other wires because of low residual stress and high adhesion condition of brass coating layer.

• Proceedings of the KSR Conference
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• 2002.10b
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• pp.981-986
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• 2002

ACSR of the catenary wires is corrosion degradation progressed by the effect of atmospheric pollution. ACSR which consists of galvanized steel stranded aluminum. The inside of Steel Reinforced is hot-dipped zinc coating steel wire and it takes charge of tension. If ACSR is exposed in atmosphere, the galvanic corrosion is occurred because it is contacted with aluminum. It is occurred the chemical reaction rapidly so that the local a defect is also occurred. If the catenary wires are exposed in atmosphere of pollution conditions, it may cause to reduce the mechanical strength by corrosion degradation and may cause to damage the wires by micro cracks. Accordingly, this study presents the effects of mechanical properties through the corrosion of ACSR.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.12
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• pp.829-834
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• 2016

Coil specimens were prepared by continuous coating on a copper wire with flexible PAI (polyamideimide) and PAI/nanosilica (5 wt%) varnish and thermally aged at 150, 200 and $250^{\circ}C$ for 5, 10 and 15 days, respectively. AC insulation breakdown voltage was investigated under inverter surge condition at 60 Hz and 1,000 Hz and insulation breakdown voltage decreased with increasing aging temperature and aging time at each 60 and 1,000 Hz.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.288-291
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• 2001

It is very important to select suspension solution for forming electrophoretic deposited YBCO thick film, because it is heavily affected to its superconducting properties. In this paper, high-temperature superconductor films of YBa$_2$Cu$_3$$O_{7-x}$ were fabricated by electrophoretic deposition (EPD) from alcohol-based suspension such as iso-propanol, iso-butanol, and their mixture. For the formation of YBCO dense and adherent coating on a silver wire by EPD, 1% PEG(1000) 2 $m\ell$, as a additive for making their surface crack-free, was used for electrophoresis. As a results, the cracks were considerably decreased and the superconducting critical current density (J$_{c}$) without/with PEG was 1200 A/$\textrm{cm}^2$ and 2020 A/$\textrm{cm}^2$, which films deposited in mix ism-propanol and iso-butanol suspension.ion.

• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.172-177
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• 2010

This study reports the high-temperature oxidation kinetics, ASR(area specific resistance), and interfacial microstructure of metallic interconnects coated with conductive oxides in oxidation atmosphere at $800^{\circ}C$, The conductive material LSC($La_{0.8}Sr_{0.2}CoO_3$, prepared by Solid State Reaction) was coated on the Crofer22APU. The contact behavior of coating layer/metal substrate was increased by sandblast. The electrical conductivity of the LSC coated Crpfer22APU was measured by a DC two probe four wire method for 4000hr, in air at $800^{\circ}C$. Microstructure and composition of the coated layer interface were investigated by SEM/EDS. These results show that a coated LSC layer prevents the formation and growth of oxide scale such as $Cr_2O_3$ and enhances the long-term stability and electrical performance of metallic interconnects for SOFCs.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.767-771
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• 1999

Poly(ester-imide)(PEI) for the electrical insulation coating was synthesized and evaluated with one-step method as well as two-step method. For the synthesis of poly(ester-imide), imide repeat unit of N,N'-(4,4'-diphenylmethane) bistrimellitimide(DID) was initially made from trimellitic anhydride(TMA) and methylene dianiline(MDA), followed by the second stage reaction of esterification. One-step reaction was performed by reaction of TMA, MDA, dimethyl terephthalate(DMT), ethylene glycol(EG), and 1,3,5-tris-(2-hydroxy ethyl) isocyanurate(THEIC) in m-cresol solvent at a time. The synthesized poly(ester-imide) was cured with xylene, P-5030K(phenol-formaldehyde resin), TK-8(TDI type blocked polyisocyanate) and tetrapropyltitanate(TPT). It was found that the content of hydroxyl group, amount of DMT, and imide repeat unit played important role for the properties of electrical insulation coating film.

• Applied Microscopy
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• v.10 no.1_2
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• pp.7-17
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• 1980

Electron microscope radioautography introduced by Liquier-Milward (1956) is now used routinely in many laboratories. Most of the technical difficulties in specimen preparation have been overcome. This method is modified from loop method for improvement of EM radioautographic techniques. The advantages of this method are: 1. the use of single specimens on small corks and of a large wire loop, allows the experimenter to avoid the blemishes in the membrane; 2. the surfactant dioctyl sodium sulphosuccinate is added to diluted ILford L4, thus greatly prolonging the period of time over which good emulsion layers can be made; 3. corks can be handled in perspex holder which allows about 20 specimens to be developed simultaneously. The steps of the method comprise: 1. Cut ribbons of ultrathin sections of silver interference colour 2. Pick them up on formvar-coated 200 mesh grids 3. Prestaining of tissues 4. Coat the specimens with a thin layer of carbon by evaporation (30-60A) 5. Mount the specimens on corks (about 1cm apical diameter) using double-sided scotch tape 6. Emulsion coating; a. Take a 250m1 beaker, place it on the pan of a sliding weight balance and weigh it. Add 10 grams extra to the beam. Add pieces of ILford L4 emulsion to the beaker until the balance is swinging freely. Add the 20ml of distilled water that was previously measured out. b. Surfactant dioctyl sodium sulphosuccinate is added to diluted ILford L4. 7. Prepare a series of membranes of gelled emulsion with the wire loop and apply one to each cork-borne specimen. 8. Put the specimens away to expose by pushing the corks into short length of PVC tubing, each tube having a small hole in the side 9. Place the tubes in small boxes together with silica gel. 10. Exposure 11. Developer - Kodak Microdol X for 3 minutes 12. Fixer - A perspex holder can be manufactured which allows 20 specimens to be developed simultaneously. 12. Fixer - 30% sodium thiosulfate for 10 minutes 13. Examination with Siemens Elmiskop 1A electron microscope