• Proceedings of the Korean Sanitation Conference
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• 2001.11a
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• pp.119-140
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• 2001

This experiment from March 1, 1998 to August 31, 2001 through XRD, XRF, SEM, EDS had effects as follows. 1. According to the results of test using XRD and EDS, we found that the main ingredients causing corrosion of steel pipe was ${Fe_2}{O_3}$, that of cast iron pipe was $CaCO_3$. 2. The main ingredient of corrosion products in a water pipe was Fe. On an average Fe occuied 93.36% of corrosion products in case of steel pipe while it did 85.47% in case of cast iron pipe. 3. In case of a piped water passed through SCALE BUSTER over 10 times, the corrosion products decreased largely by the galvanic effect and sacrifical anode caused by the concerntration of Zn.

• Journal of the Korean Vacuum Society
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• v.19 no.5
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• pp.326-330
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• 2010

The surface oxidation of magnesium was performed by burning and PEO treatment method. The scanning electron microscopy (SEM), EDS, and I-V characteristics have been applied to the study of the oxidation status. The sample formed by buring method shows weaker corrosion-resistant property than that by PEO method, but this shows more conducting property.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.851-854
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• 2009

최근 화석에너지 고갈과 환경규제 강화로 신 재생에너지 개발 및 보급이 시급해지고 있다. 여러 가지 신재생 에너지 중 폐기물을 이용하는 방법이 에너지원의 잠재적 가치를 비교하였을 때 가장 유망한 에너지원으로 인정되고 있으며, 그 중에서도 폐기물을 고체연료로 가공하는 고형연료가 현실적이고 경제적인 방법으로 인정받고 있다. 하지만 Cl이나 중금속 같은 물질들은 부식성이 강하여 보일러와 같은 열 회수 장치에 고온부식을 일으켜 고형연료의 제한적인 요소로 작용하고 있다. 따라서 울산의 산업단지의 고형연료의 원료가 되는 몇몇 물질을 SEM-EDS로 분석하고, Triangle plot을 통하여 나타내고 고형연료의 처리장치 설계 시 기초가 되는 자료를 제공한다.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.77-77
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• 2010

Plasma electrolyte oxidation(PEO) 표면처리된 Mg 합금을 Scanning electron microscopy(SEM) 방법으로 표면에 형성된 산화 막을 조사 분석하였다. 측정은 상온에서 수행하였다. Burning 및 PEO 방식의 표면처리 방법을 통해 제작 된 시료의 산화막을 SEM, EDS 및 I-V 측정을 통해 분석하였다.

• Journal of the Korean Geotechnical Society
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• v.28 no.9
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• pp.85-95
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• 2012

The method of using organic acid is more environment-friendly for it improves the strength of the ground. The method of proliferating microbes makes soil particle bonded, finally improves the strength of the ground and decreasing permeability. Although there has been the research on the effect of strength increasing, there has never been a research on the evaluation of field application. In this paper, through the light drop weight test, the dynamic cone penetration test, the field density test, the variation of strength was investigated in the mixed ground with organic acid for 56 days. As the results of the field test, it was found that the strength and stiffness of the ground increased with organic acid, and that through SEM-EDS, the precipitation of calcium carbonate made by specified microbe obviously increased with organic acid material and so the ground was improved. Therefore, the sustainable development of this method needs to be analysed more in the future.

• Journal of Pharmacopuncture
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• v.25 no.4
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• pp.382-389
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• 2022

Objectives: The Korean Industrial Standard (KS) for sterile acupuncture needles was established in 2009 based on research on the quality control of acupuncture needles. We aimed to determine the quality of acupuncture needles available in South Korea in 2021 by examining their surface condition and chemical composition using field-emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDS). Methods: In South Korea, there are 23 brands of acupuncture needles, and we examined 10-15 needles from each brand, resulting in a total of 285 needles. The microstructures of the needles were assessed by SEM. Using SEM images, we evaluated the acupuncture needle tips for the following defects/aspects: scratches, lumps, detached coating, bent tip, and tip sharpness. EDS was used to determine the chemical composition of the selected acupuncture needles. Results: Overall, 88.4% of 285 needles were found to have at least one type of abnormality. The most frequently observed abnormalities were scratches and dents on the surface (68.1%), followed by detached coating (63.2%), and lumps (61.8%); blunt tips were observed in about 24% of them. Of 252 needles with at least one defect, 86.9% had two or more types of defects. The ratio of the number of needles with any defect to that of needles without any defect varied among brands, ranging from 50% to 100%. Regarding foreign materials, higher proportions of Si and O were observed on the needles, indicating incomplete or detached silicone coating. Conclusion: The quality of acupuncture needles varied among brands, suggesting that further improvements can be made through various inspection methods.

• Journal of the Mineralogical Society of Korea
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• v.29 no.2
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• pp.79-87
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• 2016

Asian dust (Hwangsa) interacts with light, atmospheric gas, aerosol, and marine ecosystem, affecting Earth climate. Mineralogical properties are essential to understand the interaction between the dust and environments. In this study, we examined the mineralogical properties of Asian dust collected at Deokjeok Island, Incheon, Korea in February 22, 2015. X-ray diffraction (XRD) analyses showed that phyllosilicate minerals (62 wt%) dominate the Asian dust. Illite-smectite series clay minerals (55%) were common with minor chlorite (5%) and kaolinite (2%). Non-phyllosilicate minerals were quartz (18%), plagioclase (10%), K-feldspar (4%), calcite (4%), and gypsum (1%). Similar results were obtained by mineral quantification using scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). Transmission electron microscopy combined with EDS confirmed illite-smectite series clay minerals as the dominant phyllosilicate type. Morphological analyses using SEM showed clay agglomerates, clay-coated quartz, feldspars, and micas. Gypsum grains were common on the particle surface, while calcite nanofibers, previously reported as common on the surface, were rare, indicating the reaction of calcite and acidic atmospheric pollutants to form gypsum. The analytical result of 2015 Asian dust would contribute to the establishment of mineralogical base for the modeling of the interaction between Asian dust and environments.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.307-310
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• 2009

Nowadays, the usage of high strength steel has been growing in automobile industry mainly as structural parts since for its lightweight and high strength properties the oil crisis happened. Owing to poor formability, complex-shaped high-strength steel components are invariably produced through hot press forming. The high-strength steel sheets are in so me instances used with an Al-Si-coating with a view to prevent scaling of components during hot press forming. How ever, friction and fracture characteristics of Al-Si-coated high-strength steel during hot press forming process have not yet been investigated. In this paper, the formed parts which were formed in hot bending process were investigated by using EDS. SEM and nano indenter in order to analysis the coating layer behavior.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.6
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• pp.249-256
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• 2003

Samples with the nominal composition, Ag-$Bi_{1.84}Pb_{0.34}Sr_{1.91}Ca_{2.03}Cu_{3.06}O_{10+{\delta}}$ high $T_{c}$ superconductors containing Ag as an additive were fabricated by a solid-state reaction method. Samples with Ag of 10 wt%, 30 wt%, and 50 wt% each were sintered at $860^{\circ}C$~$870^{\circ}C$ for 24 hours. The structural characteristics, the microstructures and the critical temperature with respect to the each samples were investigated by XRD, four-prove methode, SEM and EDS respectively. The $T_{c}\;^{zero}$ of the sample with the 50 wt% Ag additive at the surface showed 94 K.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.11a
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• pp.76-79
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• 2003

본 실험에서는 $S0.7wt\%Cu,\;Sn3.8wt\%Ag0.7wt\%Cu$ solder와 금속층으로서의 좋은 특성을 가지고 있지만 아직 연구 보고 된 적 없는 Pt층과의 리플로 반응에 의해 형성되는 계면금속간화합물의 상 분석을 시도 하였다 또한 솔더내 Cu함량에 따른 계면금속간화합물의 변화에 대하여 연구하기 위해 $Sn1.7wt\%Cu$솔더와 Pt층의 계면반응 현상에 대한 연구도 수행하였다. $Sn0.7(1.7)wt\%Cu$솔더는 순수한 Sn과 Cu를 이용하여 중량비로 제조하였고, $Sn3.8wt\%Ag0.7wt\%Cu$솔더는 솔더페이스트를 사용하였다. 분석은 SEM, EDS, XRD를 이용하였다. 분석 결과 세 가지 무연솔더 모두에서 $PtSn_4$가 계면 금속간화합물로 존재함을 발견하였으며 $1.7wt\%Cu$를 포함한 솔더와 Pt와의 반응에서는 고용도 이상으로 첨가된 Cu에 의해 솔더 내부에 조대한 형상의 $Cu_6Sn_5$가 존재함을 SEM 및 EDS분석을 통하여 발견 하였다.