• Transactions of the Korean hydrogen and new energy society
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• v.30 no.5
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• pp.455-464
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• 2019

Experiments were conducted to investigate the sensitivity of steel plate oxidation with temperature in a simulated furnace. Used steel plates were a general steel and a high tensile steel. Porous media burner (PM burner) used in model furnace was made for uniform temperature profile. The surrounding temperature was controlled by adjusting the flow rate of the mixture in the combustor. Oxide layer analysis was performed using SEM image analysis and EDS line scanning. Both steel sheets showed a tendency to increase the thickness of the steel sheet surface oxide layer as the temperature increases, and it was confirmed that the flaking phenomenon in surface oxidation layer appeared when the temperature was above a certain temperature.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.1
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• pp.79-84
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• 2007

Mineral Trioxide Aggregate(MTA) has been used in Endodontic treatment successfully for more than 10 years. But the high cost of MTA limits its use in endodontics in Korea. Recently many studies have been done to compare MTA and Portland cements. To investigate the chemical constitutions of MTA (Proroot MTA, Tulsa Dental), Gray Portland cement (Lafarge Halla cement), White Portland cement(Union corp), and fast setting cement (SSangyong cement), we performed SEM(scanning electron microscope)(S4700, Hitachi) examination and EDS(Energy dispersive spectrometry)(emax, Horiba) analysis. SEM examination and EDS analysis were committed to and performed in SNU DRI (Seoul National University Dental Research Institute). We found that particles of MTA were relatively round, uniform in size, and compactly packed compared to Portland cements. Chemical constitutions of MTA, GPC, WPC and FSC were similar. It was shown that MTA contains much BiO2 . MTA and WPC showed less heavy metals such as Fe and Mg compared to GPC and FSC. FSC showed remarkably high aluminum content.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.3
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• pp.116-126
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• 2021

Diesel particulate filter (DPF) is a typical application field of cordierite (Mg₂Al₄Si₅O₁₈) honeycomb. Green body for DPF honeycomb was extruded using slurry paste and sintered at the temperature range of 980~1450℃. Quantitative crystal phase analysis was carried out by using Rietveld refinement method for powder XRD data. In conjunction with the quantitative Rietveld analysis, SEM-EDS analysis was carried for the crystal phases (indialite, cordierite, cristobalite, alumina, spinel, mullite, pro-enstatite). After removing amorphous phase on the sintered surfaces by chemical etching method, the shape and composition of the crystal phases can be clearly identified by SEM-EDS method. By combining the Rietveld refinement method and SEM-EDS analysis, crystal phase evolution process in DPF cordierite ceramics could be clarified. In addition, the coefficient of thermal expansion (CTE) of the DPF honeycombs were measured and compared with the calculated CTEs based on the quantitative crystal phase analysis results.

• Journal of Conservation Science
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• v.34 no.1
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• pp.51-57
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• 2018

Herein, we present the results of the analysis of a lacquer coating fragment excavated from 'Daesungdong No.88 tomb of Gimhae'. We observed the fragment with an optical microscope and used scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) as well as Fourier-transform infrared spectroscopy analysis to determine the structure of the lacquer coating and the technique used for coating. The sample was identified as a Moksim Jophy Lacquer. It is made from wood, painted with textile fabric and coated with soil clay. The SEM-EDS analysis revealed residues of bone meal at the bottom part of the sheath layer. The incorporation of bone meal in a lacquer coating layer is one of the characteristics of the Han Dynasty, and was also found in the Nangnang Region and the United Silla Dynasty. Inside the sword sheath is a specific adherent structure of silk fabric, the same type of leguminous plant found in another sword sheath excavated from the Eastern Han-tomb of Xi'an. Results constitute the latest information about lacquer ware found in the southern district of the Korean peninsula. Moreover, the findings shed light on an international relationship with Kumkwan-Kaya where the sword sheath was produced.

• The Journal of the Convergence on Culture Technology
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• v.1 no.2
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• pp.65-69
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• 2015

Teeth and bones are very resistance to high temperatures and remain recognizable even after prolonged exposures to heat. The effects of heating and burning on teeth have been studied with the aim of discerning a characteristic signature withstanding high temperature, but there have been few studies about a human cremated ash, especially Korea. We are recognizable by elemental composition and can be detected in human cremated ash samples by Scanning electromicroscopy/Energy dispersive X-ray spectrometry analysis(SEM/EDS), cremated, at $800{\sim}900^{\circ}C$ for 1 hour. In this temperature range, different crystals morphologies(spherical, irregular and hexagonal) are observed in SEM. Calcium(Ca) and oxygen(O) increases steadily after cremation in EDS. We suggest that cremated bone have been provided with calcium oxide(CaO) formation at temperature above $900^{\circ}C$. This study offers basic data to assess the structure and elemental compositions of human ash and to determine if these remain identifiable after exposure to extreme temperatures.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.551-555
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• 2010

Cinnamomum Iners (Darchini, 쟈 바 계피), Elettaria Cardamomum (Elachi, 백두구, 소두구, 카다몬, 카도몬), Punica Granatum (Anar Dana, 석류), Curcuma Longa (Haldi, 터메릭, 투메릭, 심황, 울금, 울금은, 컬쿠마), Piper Nigrum (Kali Mirch, 페퍼, 페퍼블랙, 후추, 블랙 페퍼), Syzygium aromaticum (Loung, 클로브, 정향, 정향나무,), Capsicum Annum (Laal Mirch, Red Pepper), Mentha Arvensis (Pahari Podina), Curcuma Zedoaria (Kachur, 가쥬츠, 봉출, 아출, 커큐머 제도) Zingiber officinale (Adrak, 건강, 생강, 진저) and Garam Masala (Hot Spice, a mixture) have been analyzed in the present work for their metallic components with the help of SEM-EDS and ICP-AES. Minor concentrations have been determined with ICP-AES and major concentrations with the help of SEM-EDS.

• Journal of Conservation Science
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• v.26 no.3
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• pp.247-258
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• 2010

We conducted optical microscopy, infra-red spectroscopy and SEM-EDS analysis of the lacquer layers on the wooden coffins excavated from King Muryeong's Tomb. We found four varnishing methods according to the sub-materials of lacquer layers: The lacquer of wooden coffins with black paint layer on the surface were classified with two groups; single layer and three layers. The lacquer of wooden coffins without black paint layer on the surface were classified with two groups; single layer and two layers. IR spectra of the laquer were same as those of the oriental laquer. The SEM-EDS analysis showed that the lacquer layers were mixed with iron, copper and calcium.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.368-369
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• 2003

각종 배출원에서 배출된 입자상 물질은 대기 중 확산, 이동, 침착 등을 통해 국지적 도시오염 뿐만 아니라 장거리까지도 이동함으로서 광역적 대기오염의 원인이 되고 있는 등 입자상 물질의 발생원 추적에 관한 연구가 필요한 실정이다. 지금까지 입자상 물질의 발생원 추적은 대부분 배출원의 발생량 조사나 필터에 포집된 시료의 전체적인 화학적 분석의 개념으로 단시간의 시간변동과 개개의 입자가 가지는 정보가 무시되고 평균화되고 있다. (중략)

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.4
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• pp.549-562
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• 2020

Deionized water, methanol, and ethanol were investigated for their effectiveness at dissolving LiCl-KCl-UCl3 at 25, 35, and 50℃ using inductively coupled plasma mass spectrometry (ICP-MS) to study the concentration evolution of uranium and mass ratio evolutions of lithium and potassium in these solvents. A visualization experiment of the dissolution of the ternary salt in solvents was performed at 25℃ for 2 min to gain further understanding of the reactions. Aforementioned solvents were evaluated for their performance on removing the adhered ternary salt from uranium dendrites that were electrochemically separated in a molten LiCl-KCl-UCl3 electrolyte (500℃) using scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Findings indicate that deionized water is best suited for dissolving the ternary salt and removing adhered salt from electrodeposits. The maximum uranium concentrations detected in deionized water, methanol, and ethanol for the different temperature conditions were 8.33, 5.67, 2.79 μg·L-1 for 25℃, 10.62, 5.73, 2.50 μg·L-1 for 35℃, and 11.55, 6.75, and 4.73 μg·L-1 for 50℃. ICP-MS analysis indicates that ethanol did not take up any KCl during dissolutions investigated. SEM-EDS analysis of ethanol washed uranium dendrites confirmed that KCl was still adhered to the surface. Saturation criteria is also proposed and utilized to approximate the state of saturation of the solvents used in the dissolution trials.

• Journal of Conservation Science
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• v.10 no.1 s.13
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• pp.1-9
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• 2001

The objective of this study is to examine the characteristics of historical papers and cloths found at Neunggasa temple, Goheunggun, Chonnam Province, Korea, using light microscopy, image analysis and SEM-EDS for fiber morphology and trace metal composition. All papers were made from paper mulberry. Transparent membrane, which was separated from bast fiber, was unique in these fibers. The papers found on the wall of Daewungjun were most highly degraded and those of the books, which were excavated under Cheungwangmun, were relatively well preserved. The cloths found under the statue 'Dong-bangjiguk' were silk, very narrow fiber without any marks. In the analysis of SEM-EDS, high content of silica was detected. Also small content of calcium was taken into consideration. Content of iron and chlorine were discussed from the viewpoint of potentially harmful elements for the conservation of paper. The composition of trace elements could not be used to determine the origins of papers.