• Fire Science and Engineering
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• v.18 no.4
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• pp.72-77
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• 2004

In this paper, we studied on the short-circuit process, surface structure, and component variation of vinyl cords. In the results of high speed imaging system (HSIS) analysis, as soon as wire covering was damaged by heat, the conductor of wire came in contact with the other conduct of wire, and the short-circuit occurred. Stereomicroscope and SEM analysis indicated that the source part of wire showed V-type form. The molten beads of load part were bigger than those of source part. In the results of EDX analysis, Cu and O were detected in the source part, whereas covering material (Cl, Ca), Cu and O were detected in the load part. The results will help us to find out the cause of electrical fire.

• Journal of Environmental Science International
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• v.19 no.4
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• pp.509-516
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• 2010

This study was investigated the characteristics of indoor air concentration of fiber particles in 30 public facilities and 245 schools by PCM (phase contrast microscopy). Also SEM/EDX (scanning electron microscope / energy dispersive using X-ray analysis) was used to obtain physicochemical information of asbestos fiber and to classify asbestos and non-asbestos of fiber particles. The airborne concentrations of fiber particles were $0.0009\pm0.0009$ counts/mL in public facilities and $0.0012\pm0.0006$ counts/mL in schools by PCM. All the samples were satisfied with the IAQ (indoor air quality) level of 0.01 counts/mL. In classification of 4 type shapes, over 80% of the fiber particles were identified as single fiber type. And this study analysed airborne fiber particles in 4 sites for identifying asbestos of by SEM/EDX. The asbestos fibers in most samples could not be found.

• Journal of the Korean GEO-environmental Society
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• v.11 no.10
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• pp.33-39
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• 2010

A self-organized nano-structured, photocatalytic $TiO_2$ membrane with large surface area of anatase crystallites was successfully fabricated by anodization. The nano-structured anodized $TiO_2$ membrane was characterized using EDX, SEM and XRD techniques and the effect of electrolyte type and concentration to fabricate $TiO_2$ metal membrane was also investigated. Regular nano tubular arrays were obtained By the EDX, SEM and XRD patterns, the anodized $TiO_2$ membrane showed the enhanced photocatalytic properties of anatase phase. Photocatalytic activities of fabricated $TiO_2$ metal membrane was also experimentally investigated as model compound of humic acid.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.5
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• pp.345-353
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• 1997

The purpose of the study was to stastically classify individual PM-10 measured by SEM/EDX (scanning electron microscopy/energy dispersive x-ray analyzer). The SEM/EDX provided various physical parameters like optical diameter, as well as major 18 chemical information (Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Pb) for a particle-by-particle basis. The total of 1,419 particles were analyzed for the study. Thus density and mass of each particle can be estimated based on its chemical composition. Further the study developed 4 semisource profiles including highway, oil boiler, incinerator, and soil emissions, where each sample was collected near the source in the ambient air The profiles developed were consisted of mass fractions and their uncertainties based on a particle class concept. To obtain mass fraction of each particle class, an agglomerative hierarchical cluster analysis was initially applied to create particle classes for each sample. Then uncertainties were calculated for each class based on the jacknife method. The 1,258 particles out of 1,419 (88.7%) were assorted in newly generated particle classes. The study provides opportunities to identify particle's source quantitatively and to develope various receptor models.

• Analytical Science and Technology
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• v.18 no.4
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• pp.355-361
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• 2005

The objective of this paper is to compare the surface features of two kinds of activated caron fiber (ACF) treated with potassium and the variation of their properties by phosphoric acid pre-treatment. X-ray diffraction (XRD) patterns indicate that activated carbon fiber containing potassium species show better performance for metal and metal salts by pre-treatment with phosphoric acid. In order to present the causes of the differences in surface properties and specific surface area after the samples were treated with phosphoric acid, pore structure and surface morphology were investigated by adsorption analysis and SEM. For the chemical composition microanalysis for potassium leading of the activated carbon fibers pre-treated with phosphoric acid, samples were analyzed by EDX. Finally, the type and quality of oxygen groups were determined from the method proposed by Boehm.

• Journal of Korean Society on Water Environment
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• v.27 no.6
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• pp.754-759
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• 2011

A sequencing batch reactor (SBR) was operated under different pH conditions to better understand the influence of pH to granulation in enhanced biological phosphorus removal systems. Granules from the SBR were also investigated using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Considerable decreases in the amount of phosphorus released per substrate provided under anaerobic conditions and the content of biomass polyphosphate under aerobic conditions were observed when pH was changed from 7.5 to 7.0, followed by 6.5. Aerobic granulation was also observed at pH 7.0. A number of bacteria with the typical morphological traits of tetrad-forming organisms (TFOs) were observed at pH 7.0, including large members of cluster. Filamentous bacteria were also there in large numbers. The occurrence and growth of granules were further enhanced at pH 6.5. A SEM analysis showed that the aerobic granules had a compact microbial structure with shaperical shape and morphologically consisted of aggregates of small coccoid bacteria and filamentous bacteria encapsulated by extracellular polymeric substance. The main material ions identified by EDX moreover revealed that the structural materials for polyphosphate in the granules include phosphorus, potassium and calcium. Therefore, these results strongly suggested that PAOs are a dominant population in the microbial community of the aerobic granules.

• Analytical Science and Technology
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• v.19 no.5
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• pp.376-382
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• 2006

In this work, pitch/activated carbon/$TiO_2$ composite were prepared by $CCl_4$ solvent method with different mixing ratios. The BET surface area of pitch/activated carbon/$TiO_2$ composite has a significantly increase with increasing activated carbon content in pitch/activated carbon/$TiO_2$ composite. The surface structure and elemental compositions of the composite were studied by SEM and EDX, respectively. The SEM results were presented to the characterization of porous texture on the pitch/activated carbon/$TiO_2$ composite. And EDX data was shown the presence of C, O, S, Ti and other elements. The structural properties of the composite were studied in XRD measurements. The $TiO_2$ crystal phases of the pitch/activated carbon/$TiO_2$ composite had lots of rutile-type structure which transforms from anatase-type with a little of anatase-type structure. The photocatalytic activities of the composite were evaluated using a photo-decomposition method under UV lamp. The pitch/activated carbon/$TiO_2$ composites were observed better photocatalytic activity than that of pristine $TiO_2$.

• Analytical Science and Technology
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• v.21 no.3
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• pp.229-236
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• 2008

$C/TiO_2$ composites were prepared with surface modified MWCNT sequentially after HCl treatment and TNB as titanium source. There is a single crystal structure which is anatase in all of the samples from the data of XRD. The SEM microphotographs of $C/TiO_2$ composites show that the $TiO_2$ particles were well mixed with the CNT. There are C, O and Al with strong Ti peaks in all samples from EDX results, and it also shows that the sample CT has much more amount of C and Ti content than that of sample HCT. Finally, the photocatalytic activities for the $C/TiO_2$ composites have more effective than that of pristine $TiO_2$.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.567-574
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• 2000

The purpose of this study is to examine mineralogical properties of the soft clay that is distributed widely in Samsan area, Ulsan. XRD analysis were examined to find the quantities of the clay minerals. And XRF, SEM and EDX analysis were also examined to investigate the chemical compositions and the structures of the clay. The properties of the samples from 2 sites in Samsan area were that the minerals of the clay were illite, kaolinite, chlorite, smectite and etc.. The plenty of illite has 38 to 53% of content in whole study area. And kaolinite had 18 to 30%, chlorite had 15 to 25%, and smectite had 4 to 12% of content, respectively. The results of SEM observation showed that appearances of Ulsan clay were sheet, plannar or needle form. Ulsan clay included the salt crystal of cubic and the foraminifera, which were related with the content of organ.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.379-391
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• 2010

In order to understand the mechanism of cementation of soft soils treated with bacteria, three types of specimens(untreated, normal bacteria concentration treated, and high bacteria concentration treated) were made. Scanning Electron Microscope(SEM), EDX and X-ray diffraction(XRD) analyses were performed on the soft silt and loose sand specimens. Compared with the untreated specimen, a clearer cementation between particles was observed in the high bacteria concentration treated specimen. Based on the scanning electron microscope(SEM) EDX analyses, more calcium carbonate was observed in the specimen treated with high bacteria concentration than other specimens. On the basis of the preliminary results, it appears that microbial cementation can occur in the soft soil. Further study on the cementation of soils using bacteria is necessary to validate this result.