• Progress in Superconductivity
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• v.1 no.1
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• pp.51-55
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• 1999

A Ni/Ag/Stainless steel 310S(SS310S) multi-layer sheet has been fabricated by a combination of vacuum brazing, cold rolling and texture annealing processes. After heat-treating the thin Ni/Ag/SS310S multi-layer sheet at $900^{\circ}C$ for 2h, development of (100)<001>cube texture on Ni surface was revealed by (111) pole figure. Quantitative chemical analysis was made by EPMA for the cross-section of the Ni/Ag/SS310S multi-layer sheet. EPMA results showed that Ag diffusion into the Ni layer, which may suppress the cube texture development, was negligible. A small amount of Cr atoms were detected in the Ni layer. It showed that Ag can be used as a chemical barrier of alloying element atoms in Ni layer for the Ni/Ag/SS310S multi-layer sheet and a strong cube texture was developed for the Ni layer in the Ni/Ag/SS310S multi-layer sheet.

• Korean Journal of Crystallography
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• v.7 no.1
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• pp.20-29
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• 1996

Sr0.6Ca0.4CuO2 single crystal has been synthesized by flux method and characterized by the single crystal X-ray diffraction. The compound has the orthorhombic system and the space group is Cmcm(63), lattice parameters are a=3.4645Å, b=16.1417Å, c=3.8727Å. In the (Sr1-xCax)CuO2 compound the limit of Ca from substitution for Sr was determined by the change of bond length. For this, X-ray diffraction, scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDAX) and electron probe micro-analysis (EPMA) were used. From the change of Cu-O bond length as the Ca substitution, we concluded the limit of Ca incorporation Xca≒0.73.

• 한국전자현미경학회:학술대회논문집
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• 1994.05a
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• pp.31-31
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• 1994

• Journal of the Mineralogical Society of Korea
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• v.16 no.3
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• pp.233-243
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• 2003

Microstructures and chemistry of anorthoclase, a high-temperature phase of alkali feldspars, were studied using EPMA and TEM. BSE images of anorthoclase displayed mixtures of Na-rich areas and K-rich areas forming lamella of various sizes. EPMA analysis indicated that the Na-rich area is composed of Ab: 81%, Or: 3% and An: 11% in average, while the K-rich area is composed of Ab: 45%, Or: 44% and An: 11 % in average. TEM analysis revealed albite with Albite twins in the Na-rich area, contrasting to mixtures of albite with fine Albite twins and orthoclase without twins, forming regular lamella of about 100 nm sizes, in the K-rich area. The [001] electron diffraction pattern of the K-rich area also indicated coexistence of the two phases. While streaking parallel to the (010)$^{*}$ direction appeared only in albite due to the twin structure, streaking parallel to the $(100)^{ *}$ direction appeared both in albite and orthoclase, probably due to strain on the interface as well as order-disorder phenomena of Al and Si. It is suggested that the reverse orientation of albite and orthoclase is caused by pole switching to reduce strain on their interfaces. Based on these observations and analyses, the mineral studied is identified as lower-temperature cryptoperthite rather than high-temperature anorthoclase, which has a midium degree of Al-Si ordering and $400^{\circ}C$∼$600^{\circ}C$ of estimated temperatures for the microstructure formation.

• Korean Chemical Engineering Research
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• v.44 no.4
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• pp.375-381
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• 2006

In this sturdy, spherical activated carbon(SPAC) contained $TiO_2$ was made by ion-exchanged treatment and heat treatment for applying fluidizing bed system. The ion-exchange resin was treated by $TiCl_3$ aqueous solution. The treated resin and raw resin were heat-treated under nitrogen condition to convert into Ti-SPAC. During the heat-treatment, burn-off weight amounts and the element were measured by means of TGA and TGA/MS, individually. The physicochemical properties of Ti-SPAC was characterized by means of XRD, SEM, EDS, BET, EPMA, ESR, intensity and titanium content. The Ti-SPAC had spherical shape with diameter size about $350{\mu}m{\sim}400{\mu}m$ and $617m^2/g$ specific surface area. Structure of $TiO_2$ in Ti-SPAC was anatase and rutile form. Also, $TiO_2$ on SPAC were found that the $TiO_2$ were uniformly distributed through EPMA analysis. Moreover, the Ti-SPAC showed indirect photocatalyst activity estimation through ESR analysis, characteristics of photocatalyst potentially. Over all results, Ti-SPAC was used in fluidizing bed UV/photocatalyst system to remove HA(Humic Acid). That results were HA removal efficiency was about 70％ and Ti-SPAC intensity was preserved during reaction. Ti-SPAC showed practical possibility as photocatalyst in fluidizing bed system.

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.3
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• pp.550-568
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• 1995

The purpose of this study was to observe the effects of early functional on bone formation around titanium plsama sprayed IMZ implants. 15 IMZ implants were inserted on the mandibular premolar areaa in 5 mondgrel dogs. The inplants were divided into 4 groups according to it’s loading schedule : Temporary abutments were connected for functional loading 6weeks, 9weeks, and 12weeks after implants installation in group I, II, and III, respectively. Abutments were not connected in the control group. After polyfluorochrome sequential labeling, all animals were sacrificed and bone sections includig implants and the 1st. molar were removed and processed for histologic evaluation. From light and fluorescence microscopic evaluation as well as histomorphometric and EPMA analysis, following results were obtained : 1. Light microscopically, the osteoid tissues were observed much in the compact bone of unloaded group, and cancellous bone formation observed more in early loaded group. 2. Calcification and remodeling of bone took place faster in loaded group, especially in 6 weeks group. 3. Moderate to severe marginal bone resorption was observed in 6 weeks group, mainly on buccal crest. 4. There was no difference in the percentages of bone-to-metal contact among the experimental groups. 5. In quantitative analysis using EPMA, there was no difference in the content of calcium and phosphorus among the experimental groups, regardless of distance.

• Journal of the Korean Ceramic Society
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• v.40 no.8
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• pp.746-750
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• 2003

Using the Czochralski method, Er$_2$O$_3$ doped near stoichiometric LiNbO$_3$ single crystals were grown 15~20 mm in diameter and 30-35 mm in length for Z-axis. Lattice constants were inspected by the X-Ray Diffractometer (XRD) and through Fourier Transform-Infrared Spectrophotometer (FT-IR), it observed absorption band. Also, the distributions of Er concentration were confirmed by the Electron Probe Micro Analysis (EPMA).

• Nuclear Engineering and Technology
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• v.30 no.6
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• pp.518-530
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• 1998

A natural analogue study has been performed for the Koongarra uranium ore deposit in Australia as an international agreement of the Analogue Studies in the Alligator Rivers Region (ASARR). Rocks obtained from the Koongarra deposit, Northern Territory of Australia, were examined in order to understand uranium migration processes of primary and secondary ore-body in both weathered and unweathered zones. Total alpha activities of rock samples were measured to compare the relative amount of uranium in the sample. Uranium distributions have been investigated by means of both the alpha-autoradiography and the fission track registration technique after irradiation in a flux of thermal neutrons (~10$\times$$10^{13}$nㆍ$cm^{-2}$ㆍs$^{-1}$) for 2 minutes. The mineral phases corresponding to the registered alpha-tracks and fission tracks were identified by petrological observation with optical microscope as well as X-ray diffraction and electron microprobe analysis (EPMA). Uranium was found mostly inside of the fracture of the quartzite and its mineral phase was identified as sklodowskite. The mineral phase associated with high uranium concentration was found as illeminite by petrological observation with optical microscope as well as EPMA.

• Journal of Integrative Natural Science
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• v.4 no.1
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• pp.58-71
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• 2011

The precambrian gneisses are widely distributed in the Jangsu area. This study focuses on the metamorphic mineral assemblages and metamorphic P-T conditions of the gneiss. We have analyzed garnet, biotite and plagioclase among the gneiss through the EPMA analysis, and calculated the metamorphic temperature and pressure accordingly. The metamorphic temperature was estimated by the average of values from the garnet and biotite formulas, and the metamorphic pressure by value of the Hoisch(1990) geopressured on garnet-biotite-plagioclase. The mineral sample we examined shows garnet-biotite-plagioclase-quartz composite and garnet-plagioclase-orthoclase-quartz composite. Garnet shows almandine-pyrope solid solution in general, while porphyroblastic gneiss shows almandine-grossluar solid solution. The fact that the abundances, observed by garnet profile, are almost identical in both the central region and the outer egion indicates that the crystal was developed uniformly. There is almost negligible variance in biotite on metamorphic grade, and andesine is observed in plagioclase. The metamorphic temperature and pressure from EPMA analysis and its indications are as follows: the middle-temperature, high-pressure metamorphism ($500-650^{\circ}C$, 6.9-10 kbar) ensued in the beginning, and then was followed by the high-temperature, middle-pressure($600-740^{\circ}C$, 2.7-5.9 kbar) to ($500-540^{\circ}C$, 3.1 kbar) retrograde metamorphism.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.3
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• pp.75-86
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• 1991

Ion exchange strengthening is a chemical process whereby large alkali ions(such as potassium) are substituted for smaller ions(sodium) within the surfaces of glasses and ceramics, thereby reducing the thermal expansion coefficient of this surface region, and creating beneficial state of compressive stress within the near surface region. The purpose of this study was to determine the effects of ion exchange and etching treatments on the strength of some dental porcelains. Two feldspathic dental porcelains(Vitadur-N, G-Cera) were used in this study. A commercial ion exchange paste and etching gel containing 8% hydrofluoric acid were used for surface conditioning. Transverse strength was measured using a universal testing machine and the technique of EPMA(electron probe micro analysis) was used to access the potassium contents. The results were as follows: 1. Improvement in strength was only obtained by treating the surface placed in tension. 2. No changes in the dimensions of the treated specimens were detected when samples were measured with a micrometer. 3. There was significant increase in transverse strength of G-Cera IV group treated with etching and ion exchange, compared with G-Cera II group only treated with ion exchange. 4. From the results of EPMA test, increase in potassium contents was observed on the surface treated with ion exchange paste.