• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.495-498
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• 2009

To improve the efficiency of the high voltage cable for BLU(backlight unit) of TFT-LCD(Thin Film Transistor-Liquid Crystal Display), the analysis for the trial products(UL3239, UL3633) is conducted by using SEM(scanning electron microscope) and EDX(Energy Dispersive X-ray Spectroscopy). The result that it is possible to accumulate the know-how to about stranding pitch through effective improvement of stranding process. The troubles which are the badness of withstanding voltage and tensile strength etc. are solved by development of excellent material. Furthermore, phenomenon of conductor unfasten in the harness work is solved by improvement of the stranding wire process.

• Journal of Power System Engineering
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• v.11 no.4
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• pp.92-97
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• 2007

This study aims at investigating the wear behavior of thermally sprayed Ni-based self-flux alloy coatings against different counterparts. Ni-based self-flux alloy powders were flame-sprayed onto a carbon steel substrate and then heat-treated at temperature of $1000^{\circ}C$. Dry sliding wear tests were performed using the sliding speeds of 0.2 and 0.8 m/s and the applied loads of 5 and 20 N. AISI 52100, $Al_2O_3$, $Si_3N_4$ and $ZrO_2$ balls were used as counterpart materials. Wear behavior of Ni-based self-flux alloy coatings against different counterparts were studied using a scanning electron microscope(SEM) and energy dispersive X-ray spectroscopy (EDX). It was revealed that wear behavior of Ni-based self-flux alloy coatings were much influenced by counterpart materials.

• Journal of the Korean Society for Heat Treatment
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• v.4 no.3
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• pp.21-30
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• 1991

Microstructural analysis was conducted to observe the effect of aging treatments in a Cr-Mn austenitic stainless steel containing nitrogen, and the amount, size, shape and distribution of precipitates were investigated. It was found that on water quenching from $1000^{\circ}C$ after holding 3 h at that temperature, the steel contained no precipitates observable by optical microscopy. Precipitation of phases begins at places most favorable for the formation of nuclei-in the boundaries of grains and twins. Precipitates were studied in detail by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Chemical compositions of precipitates were examined by the use of scanning transmission electron microscopy (STEM) together with an energy dispersive X-ray (EDX) microanalysis. Also chromium depletion adjacent to grain boundary precipitates was investigated by the use of Auger electron spectroscopy (AES) for a direct examination of the fracture surface chemistry.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1557-1559
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• 2000

In this paper, we intend to establish the judgement of electrical fire through analysis of PT(Potential Transformer) using the power installation. The columnar structure and the void generated by abrupt heat grew at the tenter of boundary-face on the metallurgical microscope analysis. The detection of OK lines was confirmed by EDX(Energy Dispersive X-ray spectroscopy) as melting and recombination due to the layer-short of the wiring. We found that the thermal-weight decrease occurred at 300$^{\circ}C$ in case of being the thermal-deterioration on the base of the result that analyzed the insulated-materials by using TGA, and the thermal reaction limited-value of PT insulator was about 300$^{\circ}C$ on the DSC curve. As this analysis, we confirmed what the layer-short appeared in the wiring of PT.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3571-3574
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• 2011

Nano-scaled metal oxides have been attractive materials for sensors, photocatalysis, and dye-sensitization for solar cells. We report the controlled synthesis and characterization of single crystalline $TiO_2$ nanowires via a catalyst-assisted vapor-liquid-solid (VLS) and vapor-solid (VS) growth mechanism during TiO powder evaporation. Scanning electron microscope (SEM) and transmission electron microscope (TEM) studies show that as grown $TiO_2$ materials are one-dimensional (1D) nano-structures with a single crystalline rutile phase. Also, energy-dispersive X-ray (EDX) spectroscopy indicates the presence of both Ti and O with a Ti/O atomic ratio of 1 to 2. Various morphologies of single crystalline $TiO_2$ nano-structures are realized by controlling the growth temperature and flow rate of carrier gas. Large amount of reactant evaporated at high temperature and high flow rate is crucial to the morphology change of $TiO_2$ nanowire.

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.248-250
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• 2002

본 논문은 당뇨병의 지표물질인 glucose의 농도를 극미량의 시료를 사용하여 정량 할 수 있는 방법을 개발하기 위하여 효소 고정화 전극을 제작하였다. 전극은 실리콘 웨이퍼상에 마이크로 크기의 전극을 반도체 공정을 이용하여 제작하였고, 전기 화학적 방법으로 마이크로 전극에 전도성 고분자 Polypyrrole(PPy) 및 glucose oxidase(GOx)를 고정화한 고감도의 전기화학 전극을 개발하였다. 도전성 고분자의 전기 화학적 중합은 순환 전압 전류법으로 하였으며, 용액의 액성에 따른 효소의 표면 전하를 이용하여, 도전성 고분자를 코팅한 전극에 일정한 전압을 인가하고 GOx를 도우핑 하였다. 제작된 전극은 시간대 전류법으로 glucose의 농도에 따른 감도 측정결과 마이크로 리터의 시료에 $5{\mu}A$/decade를 얻었다. 전극의 표면분석은 Scanning electron microscopy(SEM), Energy dispersive X-ray spectroscopy(EDX)를 이용하였다.

• Journal of Technologic Dentistry
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• v.41 no.2
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• pp.71-80
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• 2019

Purpose: In this study, to evaluate the effect of oxide changes on the shear bond strength according to the composition of Ni-Cr alloys for porcelain fused matal crown, T-4 alloys, Zeroy alloys and Zeroy-X alloys were selected. Methods: 20 specimens were fabricated using selected Ni-Cr alloys and porcelain powders. A Ni-Cr alloy having a diameter of 5 mm and a height of 25 mm was produced and the metal surface was polished. Porcelain powder was fired on the polished metal surface to a diameter of 5 mm and a height of 3 mm. The experiment group consisted of three groups, T-4(TNA), Zeroy(ZNA) and Zeroy-X(ZXA). The fabricated specimens were mounted on a jig of a universal testing machine(UTM) and fracture strength was measured by applying a shear force at a UTM crosshead speed of 0.5 mm/min. The fracture strength was calculated as the bond strength between the porcelain and the alloy. The surface of the fractured alloy was analyzed by X-ray diffraction(XRD) and scanning electron microscopy(SEM), and the components of the oxide were measured by energy dispersive X-ray spectroscopy(EDX) line profile method. Results: In SEM, XRD and EDX analysis, yttrium tended to increase the mechanical and chemical bonding forces. The shear bond strength of ZXA group containing yttrium showed the highest value at 27.53 MPa. Conclusion: Based on the results of this study, it is considered that the yttrium-added Ni-Cr alloy is clinically acceptable in porcelain shear bond strength.

• Journal of Oral Medicine and Pain
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• v.36 no.3
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• pp.161-167
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• 2011

Sialolith is one of the most common pathologic conditions found in the salivary glands. The mechanisms responsible for the formation of sialoliths have not been elucidated so far. In this article, the chemical composition and micromorphology of a sialolith of a 58-year old female patient suffering from chronic sialoadenitis of the submandibular gland was analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). In a SEM evaluation, the highly mineralized amorphous core surrounded by lamellar and concentric structures was revealed, however no foreign body, organic material, or signs of microorganism were observed in the core of the sialolith. EDX analysis showed the central core was composed of only Ca, O and P, and that a high level of C was detected near the central area as well. These results indicated that the inorganic composition of the sialolith was hydroxyapatite crystals, and that inorganic and organic substances existed around the central cores. This study suggests that the sialolith was composed mainly of hydroxyapatite crystals and the formation of the nucleus of the sialolith in the submandibular gland duct was secondary to sialadenitis, which favors the growth of an inorganic crystalline nucleus.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1613-1616
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• 2012

Ni nanoparticles-$TiO_2$ nanotube arrays (Ni/$TiO_2NTs$) composites were prepared by pulsed electrodeposition method and subsequently characterized by means of field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). The FESEM results showed that highly dispersed Ni nanoparticles were not only loaded on the top of the $TiO_2NTs$ but also within the tubular structure, and the particle size of Ni prepared at different current amplitude (100, 200 and 300 $mA{\cdot}cm^{-2}$) was in the range of 15 to 70 nm. The electrochemical studies indicated that Ni nanoparticles loaded on the highly ordered $TiO_2NTs$ are readily accessible for electrochemical reactions, which improve the efficiency of the Ni nanoparticles and $TiO_2NTs$. A maximum specific capacitance (27.3 $mF.cm^{-2}$) was obtained on the Ni/$TiO_2NTs$ composite electrode that prepared at a current of 200 $mA.cm^{-2}$, and the electrode also exhibited excellent electrochemical stability.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.6
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• pp.747-756
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• 2012

The purpose of this study was to investigate adsorption characteristics of organo-clays for removal of p-xylene. As part of efforts to examine the adsorption capacities of some organo-clays for p-xylene, batch isotherm tests were carried out. Organo-clay minerals were synthesized under hydrothermal conditions using Na-montmorillonite as host clay and dimethyldioctadecylammonium (DMDA) bromide and benzyldimethyldodecylammonium (BDDA) chloride as organic surfactants, respectively. All synthetic organo-clay minerals were characterized by powder x-ray diffraction (XRD), scanning electron microscope (SEM) and energy-dispersive x-ray spectroscopy (EDX). The modification using dimethyldioctadecylammonium (DMDA) bromide showed the higher adsorption ability for p-xylene than benzyldimethyldodecylammonium (BDDA) chloride. On the other hand, the maximum adsorption capacity, $Q_{max}$ of DMDA modified montmorillonite estimated by Langmuir model was 27.0 mg/g, which was the higher value than other organo-clays.