• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.645-647
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• 2009

We investigated vertical liquid crystal (LC) alignment effects of a self-assembled-monolayer (SAM) prepared on an anisotropic $SiO_2$ surface where the field-induced LC reorientation produced a uniform single domain texture. We compared the results with the homeotropic-to-random planar reorientation results shown in LCs aligned on a SAM surface prepared on an isotropic $SiO_2$ surface.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.610-612
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• 1999

In this study, we used both displacement-current method and BAM(Brewster-Angle Microscope) to study on the molecular orientation of monolayer on the water surface. The displacement-current method measured behaviors of molecules by current and BAM was shown to be sensitive to film anisotropy even when the molecules were not tilted as long as the unit cell was anisotropic. Every transition was visible with BAM technique, either as a dramatic change in decree of contrast or as a sudden alteration of the mosaic domain texture.

• The Journal of the Petrological Society of Korea
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• v.16 no.2 s.48
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• pp.59-72
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• 2007

Kilauea volcano located in the southern part of Hawaii island chains has been formed by continuous and sporadic eruption activities from 16 century to September of 1982. Kilauea volcano was investigated from collecting the samples of basalt to identify the geochemical characteristics of the lavas. Olivine, clinopyroxene, plagioclase, and opaque minerals with glass groundmass are observed. Clinopyroxene formed glomerophopyritic texture with plagioclase and zoning texture was observed in some of plagioclase phenocrysts. Major elements such as $K_2O$, $P_2O_5$, $TiO_2$ increased with respect to MgO. $Al_2O_3$ and CaO show the kink on Marker diagram due to the crystal fractionation of plagioclase and clinopyroxene with plagioclase respectively. Olivine has a wide range of Fo% ranging from 60 to 90, and MnO and FeO in the olivine are decreased with increasing Fo% oppositely increased $SiO_2$, MgO, and NiO. Ni in the whole rock is controlled not only by the mode of olivine but also by the Ni abondance in the olivine.

• Progress in Superconductivity
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• v.5 no.1
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• pp.75-79
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• 2003

YBCO films were deposited with various thicknesses from 100nm to 1.6$\mu\textrm{m}$ on single crystal $SrTiO_3$ substrates by pulsed laser deposition (PLD). The effects of different deposition conditions, especially different deposition rates by means of changing the pulsed laser frequency up to 200Hz, on the J$_{c}$ value were studied. For YBCO film with the thickness of 200nm, the $J_{c}$ value of $2.1MA/\textrm{cm}^2$ has been achieved under the high deposition rate of 3.2nm/s (190nm/min). The $J_{c}$ can be maintained greater than $1M/\textrm{cm}^2$ with the thickness less than 1$\mu\textrm{m}$. The X-ray analysis was used to examine the texture, crystallization and surface quality. The SEM was employed to analyze the surface of YBCO, and it was shown the surface of YBCO film became rougher with increasing the thickness. There were many large singular outgrowths and networks of outgrowths on the surface of YBCO films which lowered the density of thick YBCO film. The outgrowth network was probably the a-axis YBCO corresponding to XRD $\theta$-2$\theta$scan and $\chi$-scan which were used to characterize a-axis orientation of YBCO film. The reason for J$_{c}$ declining with increasing the thickness was studied and discussed.sed.

• Journal of the Korean Magnetics Society
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• v.12 no.4
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• pp.132-136
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• 2002

Enhancement of crystallinity and exchange bias characteristics for NiFe/FeMn/NiFe trilayer with Si buffer layer fabricated by ion-beam deposition were examined. A Si buffer layer promoted (111) texture of fcc crystallities in the initial growth region of NiFe layer deposited on it. FeMn layers deposited on Si/NiFe bilayer exhibited excellent (111) crystal texture. The antiferromagnetic FeMn layer between top and bottom NiFe films with the buffer Si 50 ${\AA}$-thick induced a large exchange coupling field Hex with a different dependence. It was found that H$\sub$ex/ of the bottom and top NiFe films with Si buffer layer revealed large value of about 110 Oe and 300 Oe, respectively. In the comparison of two Ta and Si buffer layers, the NiFe/FeMn/NiFe trilayer with Si could possess larger exchange coupling field and higher crystallinity.

• Progress in Superconductivity
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• v.8 no.1
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• pp.71-74
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• 2006

High $J_c$ over 1 $MA/cm^2$ YBCO film has been successfully prepared using nitrate precursors by spray pyrolysis method. Aerosol drolpets generated using a concentric spray nozzle were directly sprayed on a $LaAlO_3$(100) single crystal substrate. The cation ratio of precursor solution was Y:Ba:Cu=1:2.65:1.35. The distance between nozzle and substrate was 15 cm. Deposition temperature was ranging from $750^{\circ}C\;to\;800^{\circ}C$. Deposition pressure was 100 Torr, and oxygen partial pressure was varied from 10 Torr to 50 Torr. The microstructure, phase formation, texture development and superconducting properties of deposited films were largely changed with oxygen partial pressure. Deposited films showed a texture with(001) planes parallel to substrate plane. High quality film was obtained when film was deposited at $760^{\circ}C$ with an oxygen partial pressure of 30 Torr. The critical current density($J_c$) of the YBCO film was 1.75 $MA/cm^2$ at 77 K and self-field.

• Progress in Superconductivity
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• v.8 no.1
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• pp.75-80
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• 2006

[ $Yb_2O_3$ ] films were successfully deposited on a cube-textured Ni and(100) $SrTiO_3$(STO) single crystal substrates by metal organic chemical vapor deposition(MOCVD) method using $H_2O$ vapor as an oxidant. $H_2O$ vapor was used in order to avoid the oxidation of Ni substrate. The working pressure and Ar flow rate were 10 Ton and 600 sccm, respectively. $Yb_2O_3$ films on STO were formed at high temperatures above $900^{\circ}C$. While XRD peaks from $Yb_2O_3$ were hardly detected at $900^{\circ}C$, the $Yb_2O_3$(400) texture was developed fur the films grown at deposition temperatures above $950^{\circ}C$. The AEM surface roughness of $Yb_2O_3$ film, grown on STO, was in the range of $6{\sim}10nm$ for the film deposited at $950^{\circ}C$ with a $H_2O$ vapor partial pressure of 5.5 Ton and deposition times of 3 and 5 mins. For cube-textured Ni substrate, both $Yb_2O_3$(222) and $Yb_2O_3$ (400) textures were developed textures at deposition temperatures above $850^{\circ}C$.

• The Journal of the Petrological Society of Korea
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• v.23 no.4
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• pp.325-336
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• 2014

Even though Mesozoic Mudeungsan tuff, located within Neungju Basin, has been named several rock names, it should be named as Mudeungsan tuff due to several evidences, such as fiamme, welded texture and rock fragments in the Mudeungsan tuff. Volcanic eruption boundary between the Cheonwangbong and Anyangsan areas is not clear, but petrochemical and mineral chemical evidences with different ages indicate clear petrological boundary between Cheonwangbong and Anyangsan. The Mudeungsan tuffs from Cheonwangbong and Anyangsan is welded crystal tuff with dacitic composition and were generated from cogenetic calc-alkaline magma in the volcanic arc environment. Geochemical events indicate that magma beneath Cheonwangbong was seems to have been evolved from the magma beneath Anyangsan due to fractional crystallization dominated by plagioclase.

• Transactions of Materials Processing
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• v.30 no.6
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• pp.306-310
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• 2021

In this study, IF steel, which has a body-centered cubic (BCC) crystal structure, was fabricated as a 25 mm-long cube, and then processed for one cycle without intermediate heat treatment by applying MADF Ver.1 and Ver.2 processes. MADF processing was performed with graphite lubrication for each pass at room temperature. The development of the microstructure and texture was analyzed and compared by the location of the specimen using EBSD measurements of the IF steel. Vickers hardness test and miniature tensile test were also performed to analyze the mechanical properties. The coarse grain size of 742.6 ㎛ of the as-received IF steel was refined to a grain size of 53.0 ㎛ after one cycle of MADF Ver.1 processing and 27.0 ㎛ after MADF Ver.2 processing. Vicker's hardness of the as-received IF steel at 94 Hv was increased to 185.6 Hv and 191.2 Hv after one cycle of MADF Ver.1 and Ver.2 processing, respectively.

• Progress in Superconductivity
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• v.11 no.2
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• pp.123-127
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• 2010

The properties of buffer layer for thermal and chemical stability in coated conductor is a very important issue. $CeO_2$ has desirable thermal and chemical stability as well as good lattice match. In this study, $CeO_2$ was deposited by electron beam deposition. The MgO(001) single crystal and LMO buffered IBAD substrate(LMO/IBAD-MgO/$Y_2O_3/Al_2O_3$/Hastelloy) were used as substrates, which have $\Delta\phi$ values of ${\sim}8.9^{\circ}$. The epitaxial $CeO_2$ films was deposited with high deposition rate of $12{\sim}16\;{\AA}/sec$. During deposition, the change of oxygen partial pressure(${\rho}O_2$) does not cause change in c-axis texture. In case of $CeO_2$ on MgO single crystal, the substrate temperature was optimized at $750^{\circ}C$ with superior $\Delta\phi$ and $\Delta\omega$ value. Otherwise, In case of LMO buffered IBAD substrate, It was optimized at $650^{\circ}C$ with increasing its deposition thickness of $CeO_2$, which was finally obtained with best $\Delta\phi$ value of $5.5^{\circ}$, $\Delta\omega$ value of $2^{\circ}$ and Ra value of 2.2 nm.