• Journal of the Semiconductor & Display Technology
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• v.9 no.3
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• pp.41-45
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• 2010

The ZnO thin films doped with Ga(GZO) and both Ga and Ge(GZO:Ge) were deposited on glass substrate by using RF sputtering system respectively. Structural, morphological and optical properties of the films deposited in the same condition were investigated. Structural properties of the films were investigated by Field Emission Scanning Electron Microscopy, FE-SEM images and X-ray diffraction, XRD analysis. These studies showed shape of films' surface and direction of film growth respectively. It's showed that all films were deposited by vertical orientation strongly. It can be confirmed that all dopants of targets were included in deposited films by results of EDX analysis. UV-Vis spectrometer results showed that all samples had highly transparent characteristics in visible region and have similar 3.28~3.31 eV band gap. It was found that existence of all dopants by EDX analysis. Morphology and roughness of surface of each film were clearly shown by Atomic Force Microscopy, AFM images. It was found in this research that film doped with Ge more dense and stable with hardly any difference in gap energy compared to ZnO films.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2008.11a
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• pp.56-56
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• 2008

연소화학증착법(CCVD)를 이용해 IN738LC 합금에 $SiO_2$ 보호피막 코팅을 행하였다. 소스물질인 TEOS 첨가량과 증착 시간을 변화시키면서 $SiO_2$ 보호피막을 제조하였다. 증착된 코팅층은 SEM, EDX, XPS 분석을 통해 $SiO_2$층임 을 확인하였고 TGA(Thermogravimetric analysis)를 이용하여 합금의 내산화 특성을 평가하였다.

• Journal of the Korea Concrete Institute
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• v.18 no.3 s.93
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• pp.355-360
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• 2006

The Alkali-Silica Reaction(ASR) may cause a serious failure in the concrete pavements and structures. Several researches in some nations have conducted the continuous studies to prevent failure of the concrete structures by the ASR distress as well as the studies to manifest the mechanism. The researches on the ASR have not been performed affluently in Korea because the distress due to ASR has seldom been reported literarily. In this study, we tried to set up the systematic scheme practically for verifying the cause of distress due to ASR by using the visual inspections in field, the chemical method, petrographic analysis, and Electron Dispersive X-ray Spectrometer(EDX) method of Scanning Electron Microscopy(SEM) in laboratory. The chemical method, petrographic method using SEM, and X-ray method were used to verify the cause of pattern crack on the surface and internal crack in the plain concrete pavement. It can be concluded that the distress of a specific site in plain concrete pavement was mainly due to ASR. The chemical method, the petrographic method and EDX method using SEM may be the effective tools for verifying the cause of AAR distresses.

• Journal of the Korea Institute of Building Construction
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• v.11 no.4
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• pp.345-352
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• 2011

The purpose of this study was to investigate the expansion of alkali-activated mortar based on ground granulated blast furnace slag containing reactive aggregate due to alkali-silica reaction. In addition, this study was particularly concerned with the behavior of these alkaline materials in the presence of reactive aggregates. The experimental program included expansion measurement of the mortar bar specimens, as well as the determination of the morphology and composition of the alkali-silica reaction products by using scanning electron microscopy(SEM), and energy dispersive x-ray(EDX). The experiment showed that while alkali-activated ground granulated blast furnace slag mortars showed expansion due to the alkali-silica reaction, the expansion was 0.1% at Curing Day 14, showing that it is safe. After the accelerated test, SEM and BEM analysis showed the presence of alkali-silica gel and rim around the aggregate and cement paste. According to the EDX, the reaction products decreased markedly as alkali-activated ground granulated blast furnace slag was used. In addition, for the substitutive materials of mineral admixture, a further study on improving the quality of alkali-activated ground granulated blast furnace slag is needed to assure of the durability properties of concrete.

• Journal of Environmental Science International
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• v.25 no.11
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• pp.1467-1474
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• 2016

In response to the water shortage problem, continued attempts are being made to secure consistent and reliable water sources. Among various solutions to this problem, wastewater effluent is an easy way to secure the necessary supply, since its annual output is consistent. Furthermore, wastewater effluent has the advantage of being able to serve various purposes, such as cleaning, sprinkling, landscaping, river management, irrigation, and industrial applications. Therefore, this study presents the possible use of reclaimed industrial wastewater treated with Birm filters and a UF membrane, along with an analysis on membrane fouling. The preprocessing stage, part of the reclamation process, used Birm filters to minimize membrane fouling. Since this study did not consider heavy metal levels in the treated water, the analyses did not include the criterion for irrigation water quality. However, the wastewater reclaimed by using Birm filters and a UF membrane met every other requirement for reclaimed water quality standards. This indicated that the treated water could be used for cleaning, channel flow for maintenance, recreational purposes, and industrial applications. The analysis on the fouling of the Birm filter and UF membrane required the study of the composition and recovery rate of the membrane. According to SEM and EDX analyses of the UF membrane, carbon and oxygen ion composition amounted to approximately 57%, whereas inorganic matter was not detected. Furthermore, the difference in the recovery rates of the distressed membrane between acidic and alkaline cleaning was more than ~78%, which indicated that organic rather than inorganic matter contributed to membrane fouling.

• Fire Science and Engineering
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• v.22 no.2
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• pp.91-96
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• 2008

This research studied about the cause analysis of fire that was occurred in far infrared rays heater to base on the fire examples. Fire of electric heater was apt to commit error that handled an over-heating accident by judged molten mark in heat ray. Molten mark which was attached in heat ray was appeared to the form of layer short circuit by other metal material, but other metal material was not found beside the ingredient of heat wire which was mixed to an alloy of Fe-Cr-Al according to result of ingredient distribution by SEM/EDX. Also, the result of overheating experiment by layer short circuit and overvoltage showed higher febrility than normal, but there was no possibility of fire occurrence. This paper will be contributed to science for cause analysis of electric fire through analyzing physical, chemical and flame features of burnout heater on the basis of diagnosis of fire that was happened in infrared rays heater.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.9
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• pp.1284-1288
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• 2009

Identification of various inorganic compound crystals contained in solar salts, which are produced from 12 areas of Jeonnam, was firstly made by the X-ray diffraction (XRD) technique. The analysis of the XRD spectra was carried out on the basis of Joint Committee on Powder Diffraction Standards (JCPDS) data and the results of Energy Dispersive X-ray Spectrometer (EDX) measurements. In particular, the analysis of the XRD spectra supported that each solar salt contains $Na_2S$ (Shinan Jeungdo and Sinui), $KMgCl_3$ (Shinan Bigeum), $Ca(ClO_3)_2$ (Shinan Docho), $CaAl_4O_7$ (Haenam Songji), $CaSiO_3$ and $CaCl_2$ (Goheung) as inorganic compound crystals, which have not been reported for the solar salts. Also, the XRD results indicated that the solar salts maintain a cubic NaCl crystal structure without any change of lattice parameters etc. However, it was shown in the Field Emission Scanning Electron Microscope (FE-SEM) images that an external form of the solar salts has a lamination layer shape of a cubic structure, which is different from a simple cubic form for the purified salts and the reagent NaCl.

• Korean Journal of Materials Research
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• v.20 no.4
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• pp.228-234
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• 2010

In this paper, Fe-$TiO_2$ and Fe-fullerene/$TiO_2$ composite photocatalysts were prepared with titanium (IV) n-butoxide (TNB) by a sol-gel method. $TiO_2$, Fe-$TiO_2$ and Fe-fullerene/$TiO_2$ were characterized by scanning electron microscopy (SEM), Transmission electron microscope (TEM), specific surface area (BET), X-ray diffraction analysis (XRD) and energy dispersive X-ray spectroscopy (EDX). The photocatalytic activities were evaluated by the photocatalytic oxidation of methylene blue (MB) solution. XRD patterns of the composites showed that the photocatalyst composite contained a typical single and clear anatase phase. The surface properties shown by SEM presented a characterization of the texture on Fe-fullerene/$TiO_2$ composites and showed a homogenous composition in the particles for the titanium sources used. The EDX spectra for the elemental identification showed the presence of O, C and Ti elements. Moreover, peaks of the Fe element were observed in the Fe-$TiO_2$ and Fe-fullerene/$TiO_2$ composites. The degradation of MB solution by UV-light irradiation in the presence of photocatalyst compounds was investigated in complete darkness. The degradation of MB concentration in aqueous solution occurred via three kinds of physical phenomena: quantum efficiency of the fullerene; organo-metallic reaction of the Fe compound; and decomposition of $TiO_2$. The degradation rate of the methylene blue solution increased when using Fe-fullerene/$TiO_2$ compounds.

• Elastomers and Composites
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• v.44 no.3
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• pp.290-298
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• 2009

In this paper, the Fe-activated carbon fiber (ACF)/$TiO_2$ composite catalysts were prepared by a sol-gel method. The synthesized photocatalysts were used for the photo degradation of Methylene blue solution under UV light. From Brunauer-Emmett-Teller measurements (BET) data, it was shown the blocking of the micropores on the surface of ACF by treatment of Fe and Ti compound. As shown in SEM images, the ferric compounds and titanium dioxides were fixed onto the ACF surfaces. The result of X-ray powder diffraction showed that the crystal phase contained a mixing anatase and rutile structure and the 'FeO+$TiO_2$' from the composites. The EDX spectra for the elemental analysis showed the presence of C, O, and Ti with Fe peaks. Degradation activity of MB could be attributed to +OH radicals derived from electron/hole pair's reactions due to photolysis of $TiO_2$ and photo-Fenton effect of Fe.

• Journal of Technologic Dentistry
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• v.28 no.2
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• pp.355-366
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• 2006

The purpose of this study was to determine if repeated casting has a detrimental effect on the corrosion behavior of nickel-chrome casting alloys. The X-ray diffraction analysis, vickers hardness test, SEM, EDX and corrosion test were performed to determine the effects of recasting on chemical composition, microstructure, physical property, castability and corrosion behavior of nickel-chrome casting alloys. The X-ray diffraction analysis results for the cast and recast specimens of the VeraBond and the Rexillium V showed that major crystal phase contained nickel-chrome compounds, Nickel carbide and Chrome carbide. Microstructure analysis results for the cast and recast specimens of the VeraBond and the Rexillium V showed recasting has no effect on microstructure. EDX analysis results indicated the percentage of the main component nickel(Ni) in the specimens of the VeraBond showed a tendency to increase with recasting, but those of other components Carbon(C) showed a tendency to decrease with recasting, Chrome(Cr), Silicon(Si), Aluminium(Al) and molybdenum(Mo) showed no changes in the percentage. The percentage of the main component nickel(Ni) in the specimens of the Rexillium V showed a tendency to increase with recasting, but those of other components silicon(Si), carbon(C) and molybdenum(Mo) showed a tendency to decrease with recasting, chrome(Cr) and aluminium(Al) showed no changes in the percentage. The vickers hardness results for the cast and recast specimens of the VeraBond and the Rexillium V showed a tendency to decrease with recasting, but the differences for the first to fifth cast were not statistically significant. The castability results for the cast and recast specimens of the VeraBond and the Rexillium V showed a tendency to decrease with recasting, but the differences for the first to fifth cast were not statistically significant. The cast and recast specimens of the VeraBond and the Rexillium V showed no differences in the corrosion resistance. The results indicate that the VeraBond and the Rexillium V can be safely recast.