• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.3
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• pp.106-111
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• 2006

The objective of this paper is to compare the surface features of two kinds of nano-porous activated carbon fiber (NPACF) treated with potassium and the variation of their properties by phosphoric acid pre-treatment. X-ray diffraction (XRD) patterns indicate that NPACF containing potassium species show better performance for potassium and potassium 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 are investigated by adsorption analysis and SEM. For the chemical composition microanalysis for potassium loading of the NPACF pre-treated with phosphoric acid, samples were analyzed by EDX. Finally, the type and quality of oxygen groups are determined from the method proposed by Boehm.

• Analytical Science and Technology
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• v.19 no.4
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• pp.316-322
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• 2006

The removal efficiencies of silver-ACFs were associated with their surface properties such as surface area, porosity, and the electro-chemical reaction time for the silver treatments. X-ray diffraction patterns of fibers electrochemically treated with silver display diffraction peaks for metallic silver and kinds of silver chloride complexes on the fiber surface after electrochemical adsorption. The results of SEM and EDX indicate that surface reaction motive of silver-ACF prepared by electrochemical reaction are depend on time function for the chloride ion removal efficiency. Finally, Cl ion adsorbed by the silver-ACFs from the ICP analysis seems to show an excellent removal effect.

• Resources Recycling
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• v.9 no.1
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• pp.52-62
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• 2000

In order to maximize the recycling of converter slag to the more valuable fields, such as high quality aggregates for construction, cement industry and flux for ion making. It will be very important to control the compositions and properties of converter slag to suit the purpose of utilizastion. In this study, converter slag (STELCO, CANADA) was mixed with 5%~30% $SiO_2$and 7% carbon, and then reduced at $1650^{\circ}C$. After the reduction was completed, the reformed slags were cooled to room temperature in the furnace. All of the slags were then characterized using SEM-EDX, XRD and chemical analysis. Also the compressive strengths and densities of the reformed slags were measured to compare with natural aggregates. XRD analysis shows that th phases of reformed slags are changed from bredigite+merwinite mixed phases of 10% $SiO_2$added reduction to akermanite phases of 20% and 30% $SiO_2$ added reduction. But the SEM-EDX analysis revealed that the phase distribution of the reformed slags was changed very sensitively and complicately depends on the change of slag compositions. And also the properties of reformed slags are changed very much depend on the phase distribution. About one third of Cadmium and on fifth of Vanadium are remained in reduction reformed converter slag. Another heavy metal elements such as cobalt, zinc, lead are removed up to more than 90-95% of original slag. The compressive strength and density of 25% $SiO_2$ added and reformed slag is very near to natural granite. This is superior more than 10% to Thyssen's $SiO_2$ added and oxidized converter slag aggregates.

• Journal of Conservation Science
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• v.28 no.2
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• pp.119-129
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• 2012

Excavated textiles provide very important research data on the costume culture of the Joseon dynasty. In particular, dyed textiles are indispensable for textile conservation research and for restoration of remains as well as for general costume culture research. Unfortunately, a prolonged burial environment causes the colors to change and gradually fade after excavation. Therefore, it is very difficult to identify the original color. In this study, natural dyed samples of red, yellow, purple and blue were prepared and analyzed using HPLC-PDA. Dyes of colorants extracted from excavated textile remains were analyzed by HPLC. In addition, mordants were analyzed using (SEM-EDX) in order to estimate the original color. The 16~17th Century's three samples were analyzed, sample 1, and 2 from Eunjin Song's Song Mun-Chang excavated at the Songchon-dong in Daejeon, and sample 3 from Yeosan Song's Song, Hee-Jong excavated at the Mokdal-dong in Daejeon. From the HPLC results, alizarin, purpurin, and indigo were detected on sample 1, alizarin and purpurin on sample 2, ellagic acid and indigo on sample 3. Therefore they were dyed with madder and indigo (sample 1), madder (sample2), pomagranted and indigo (sample 3). Al mordant was identified on three samples.

• Mass Spectrometry Letters
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• v.7 no.2
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• pp.41-44
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• 2016

Secondary ion mass spectrometry (SIMS) is a promising tool to measure isotope ratios of individual uranium particles in environmental samples for nuclear safeguards. However, the analysis requires prior identification of a small number of uranium particles that coexist with a large number of other particles without uranium. In the present study, this identification was performed by scanning electron microscopy - energy dispersive X-ray analysis with automated particle search mode. The analytical results for an environmental sample taken at a nuclear facility indicated that the observation of backscattered electron images with × 1000 magnification was appropriate to efficiently identify uranium particles. Lower magnification (less than × 500) made it difficult to detect smaller particles of approximately 1 μm diameter. After identification, each particle was manipulated and transferred for subsequent isotope ratio analysis by SIMS. Consequently, the isotope ratios of individual uranium particles were successfully determined without any molecular ion interference. It was demonstrated that the proposed technique provides a powerful tool to measure individual particles not only for nuclear safeguards but also for environmental sciences.

• Analytical Science and Technology
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• v.15 no.6
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• pp.567-573
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• 2002

The most important and largest commercial outlet of fly ash in Korea is a replacement material of Portland cement in concrete industry. The high level of unburned carbon in ash brings about some malfunctions in concrete. Therefore, fly ash is refined to improve the quality as a concrete additive. In this process, a lot of the residual carbon is produced, and discarded now. In the present study, to find out a valuable outlet of the enriched carbon samples, the basic morphology of residual carbon in fly ash from Boryung power plant was investigated. The unburned carbon characterization included shape, size measurement, and chemical analysis was examined using scanning electron microscope (SEM) and energy dispersive X-ray spectrometer (EDX).

• Korean Journal of Metals and Materials
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• v.48 no.7
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• pp.674-682
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• 2010

Fe-fullerene/$TiO_2$ composite photocatalysts were prepared with titanium (IV) n-butoxide (TNB) by a sol-gel method. The samples 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 degradation of methylene blue (MB) solution. XRD patterns of the composites showed that the Fe-fullerene/$TiO_2$ composite contained a typical single and clear anatase phase. The surface properties shown by SEM present 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 C and Ti with strong Fe peaks for the Fe-fullerene/$TiO_2$ composite. From the photocatalytic results, the excellent activity of the Fe-fullerene/$TiO_2$ composites for degradation of methylene blue under UV light irradiation could be attributed to both the effects between photocatalytic reaction of the supported $TiO_2$, decomposition of the organometallic reaction by the Fe compound and energy transfer effects such as electron and light of the fullerene.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.2015-2020
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• 2009

$NO_x$ reduction of stationary exhaust was performed at atmospheric condition and the temperature ranging from $200^{\circ}C$ to $500^{\circ}C$ over ZSM-5 supported metal catalyst. The characteristics of the prepared catalysts were investigated using the analytical techniques such as SEM, XRD, EDX, ICP and ITR. The results of EDX and ICP analysis demonstrated that the most part of transition metal existed on the exterior surface of support. Maximum de-$NO_x$ yield over Fe/ZSM-5 shown between $380^{\circ}C$ and $400^{\circ}C$ was presumed to be due to the maximum H2 reduction rate at $400^{\circ}C$ of ITR.

• Journal of Conservation Science
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• v.33 no.2
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• pp.61-73
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• 2017

In order to identify the application techniques of wooden lacquerware artifacts, optical/polarized light microscopy, Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis (EDX) were conducted on the lacquer films of 61 wooden lacquerware artifacts excavated from the Imdang-dong site, Gyeongsan, Korea. Powdered soil, soot, and charcoal were used as a filler for the undercoat, and iron oxide ($Fe_2O_3$) was used as a red pigment. Five different applying techniques were identified for the undercoat according to the composition of the lacquer. Eight different application techniques were identified for the final coat (on the middle layer and surface layer). Totally seventeen application techniques were identified based on the combination methods of the undercoat and finalcoat. Consequently, the undercoating techniques of Imdang-dong lacquerwares were found to be similar to those of lacquerwares from excavated in other provinces. However, the use of iron oxide as a red pigment at Gyeongsang province is very characteristic compared with others.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.1
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• pp.187-199
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• 2009

Objectives : The electroacupuncture was generally has been used in oriental medicine doctors. In recent years, there have been a few studies about safety and stability of acupuncture needle in itself, but then again research of acupuncture needle safety and stability on applying electroacupuncture have been insignificant. Therefore we investigated the safety and change in mechanical characteristic of acupuncture needle in electroacupuncture therapy. Methods : We observed mechanical characteristic change by SEM(Scanning Electron Microscope) and EDX(Energy Dispersive X-ray Spectroscopy), evaluated the hardness by vickers hardness tester. We used MTT assay and cell stain to study about biocompatibility of electroacupuncture. Results : In this study, any corrosion of material, alternation of elements, and change of hardness were not observed in surface analysis using SEM and EDX. In cytotoxity evaluation using MTT assay and cell stain, cell survival rate was low when practicing the electroacupuncture for more than 3 hours. Conclusions : Change of mechanical property was not observed based on the test results using surface analysis and hardness estimation by the electroacupuncture. And considering the biocompatibility, electroacupuncture was thought to be safe in an hour based on cytotoxity evaluation using MTT assay and cell stain.