• Proceedings of the Korean Magnestics Society Conference
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• 2013.12a
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• pp.32-32
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• 2013

Using the Vienna ab initio simulation package (VASP) incorporating van der Waals interaction, we have explored structural, adsorption, and magnetic properties of Ni(111)/BN/Co(111) systems. We have found that both Ni(111) and Co(111) layers shows half metallic state, while the spacer BN layer becomes weak metal for one monolayer (ML) thickness and an insulating barrier for two ML thickness. The half metallic states in both Ni(111) and Co(111) layers are robust because it is unchanged independently on the magnetic coupling of Ni(111) and Co(111). This finding suggests that the Ni(111)/BN/Co(111) systems can be utilized for perfect tunneling magnetoresistance system. Moreover, it can be applied for potential spin injecting into semiconductor in FM/semiconductor system due to the fact that the half metallic state in FM layers at the interface will be unchanged.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.92-97
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• 1995

감염병소와 진단을 위해 여러 방사성성핵종 표지 사람비특이항체들이 임상이용되었으나, $^{123}I,\;^{99m}Tc,\;^{111}In$등 표지 핵종과 표지방법에 따른 체내동태의 차이에 대한 자료가 필요하며, 감염병소의 진단에 표준적으로 이용되어지던 $^{111}In$-oxine표지백혈구와 비교평가도 요구된다. 저자들은 $10^9$개의 포도상구균을 좌측 대퇴부에 주사하여 농양을 유발한 백서에서 $^{123}In$ 표지, iminothiolane을 이용한 $^{99m}Tc$ 표지, DTPA이용 $^{111}In$ 표지 사람비특이항체와 $^{111}In$-oxine 표지 백혈구의 체내동태 및 농양섭취율을 비교하였다. $^{123}In$-IgG는 갑상선 및 위의 방사능이 높아 체내 탈요드반응이 빠름이 시사되었으며, $^{99m}Tc$-iminothiolane IgG는 신장방사능이 높아 신장으로 IgG 또는 대사물이 배설됨을 알 수 있었다. $^{111}In$-oxine표지 백혈구는 간 및 비장의 방사능이 높았고, 혈액방사능 제거율이 가장 빨랐다. 주사 24시간 후의 농양섭취율은 $^{111}In$-DTPA IgG가 가장 높았고, 농양 대 혈액 방사능비는 $^{111}In$-oxine표지 백혈구가 가장 높았으며, $^{111}In$-DTPA IgG와 $^{99m}Tc$-iminothiolane IgG가 다음으로 비슷하였다. $^{111}In$-oxine표지 백혈구보다는 방사성핵종표지 IgG가 간편하게 이용될 수 있으며, $^{111}In$ 이 $^{99m}Tc$나 $^{123}In$보다 지연영상의 촬영에 유리함을 알 수 있었다.

• Journal of radiological science and technology
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• v.13 no.2
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• pp.43-49
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• 1990

[ $^{111}$ ]In has wide applications in nuclear medicine for labelling and in-vivo distribution studies. A method is developed for the production of carrier free $^{111}$In using the reaction $^{nat.}Cd(p,\;xn)$ $^{111}$In with MC-50 cyclotron. Carrier free $^{111}$In was separated from the irradiated metallic cadmium by liquid-liquid extraction and cation exchange chromatography. The yield of $^{111}$In at EOB is $0.8mCi/{mu}\;Ahr$ and the nuclidic purity is over 99%. $^{111}In-DTPA\;and\;^{111}In-bleomycin$ were prepared for medical study.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.3
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• pp.713-719
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• 2000

In order to Prepare the$Ge_xSi_{1-x}/Si$(111) heterosructure by solid phase epitaxy (SPE), about 1000A of Au and about 1000A Ge were sequentially deposited on the Si(111) substrate. The resulting Ge/Au/Si(111) samples were isochronically annealed in the high vacuum condition. The behaviors of Au and Ge during thermal annealing and the structural Properties of $Ge_xSi_{1-x}$ films were characterized by Auger electron spectroscopy (AES), X-ray diffraction (XRD) and high resolution transmission electron microscopy (TEM). The a-Ge/Au/Si(111) structure was converted to the Au/GeSi/Si(111) structure. Defects such as stacking faults, point defects and dislocations were found at the GeXSil-X(111) interface, but the film was grown epitaxially with the matching face relationship of $Ge_xSi_{1-x}/$(111)/Si(111). Twin crystals were also found in the $Ge_xSi_{1-x}/$(111) matrix.

• Journal of the Korean Chemical Society
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• v.17 no.5
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• pp.319-323
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• 1973

The state of carrier-free silver-111 has been studied by applying filtration method. The studies involved that the effects of pH and concentration of silver-111 in aqueous solution have been determined with membrane filters. The present studies revealed that the retainment of silver-111 on membrane filters followed Freundlish adsorption isotherm, and the adsorbed state of silver-111 was present in the form of AgOH. Also it was supposed that the formation of the non-adsorbed hydroxide of$Ag(OH)_{2}-$ may prohibit the existance of AgOH at higher pH, and it seems to be valid that the carrier-free silver-111 in aqueous solution exists in$Ag^+$state.

• Journal of the Korean Ceramic Society
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• v.33 no.2
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• pp.228-234
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• 1996

It is very important to understand the domain structures of ferroelectric BaTiO3 in the poling process. Especially because {111} twinning is frequently observed in most BaTiO3 ceramics it is required to know the relations between the ferroelectric domains and the structural twin. In this study the domain structures of a {111} twinned crystal sample were observed under a polarizing microscope. and the relation between the {111} twin and the domain configurations could be classified into two types of 'V'-shape and linear shape penetrating perpendicular to the twin boundary. Domain formation obeys the symmetry of the {111} twining when a new domain structure is developed by heat treatment and surface deformation due to domain formation is also occured symmetrically between the both sides of the{111} twin boundary. This symmetrical behavior of the domains could be interpreted with the "head-to-tall" orientation of the domains across the {111} twin boundary.

• The Korean Journal of Nuclear Medicine
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• v.31 no.4
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• pp.440-451
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• 1997

This study was designed to prospect the $^{111}In$-labelled paclitaxel as tumor imaging agent. In order to provide a taxol molecule with a functional group which is able to chelate In-111, taxol-DTPA conjugate and 2'-hemisuccinyltaxol were synthesized by esterification of taxol at C-2'on C-13 carbon with DTPA anhydride and succinic anhydride, respectively. Synthesis yield of the taxol derivatives was 34% for taxol-DTPA and 80% for 2'-hemisuccinyltaxol. Cytotoxicity of the taxol derivatives were measured by MTT method toward cell lines HT29, B16, P388, and CT26. The cytotoxic activities of the taxol derivatives were maintained, although less active than taxol. Radiolabelling of the taxol derivatives were proceeded directly with $^{111}InCl_3$ or indirectly with $^{111}In$-citrate(ligand-exchange method). The ligand-exchange method was not suitable because some precipitates appeared during the reaction. On the contrary, by direct radiolabelling method, we were able to obtain taxol-DTPA-$^{111}In$ in 100% radiochemical yield. However, 2'-hemisuccinyltaxol was not labelled by both methods. Yield and radiochemical purity of the radiolabelled com-pound were determined by HPLC, paper chromatography and instant thin layer chromatography. Taxol-DTPA-$^{111}In$ was characterized to be hydrophilic by lipophilicity test, and nearly non-adhesive to HT29, B16, P388, and CT26 by cell binding affinity test. Binding affinity of the taxol-DTPA-$^{111}In$ complex to serum proteins was also examined by protein precipitation with 30% trichloroacetic acid. The results showed that 30% of the taxol-DTPA-$^{111}In$ complex binds with serum proteins.

• Journal of the Korean Vacuum Society
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• v.15 no.1
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• pp.31-36
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• 2006

By analyzing the Ge 34 core-level photoelectron spectrum, we studied the structure of the $Li/Ge(111)-3\times1$ surface. Two surface related components tying on either side of the main bulk peak were identified in the Ge 3d spectrum. The existence and the position of the two surface components in the core-level spectrum from $Li/Ge(111)-3\times1$ is similar to those of the $Li/Ge(111)-3\times1$, suggesting the similarities in structure of the two surfaces. The core-level photoelectron spectra of the Li-induced $Li/Ge(111)-3\times1$ surface are well consistent with the honeycomb-chain-channel model, which was proposed as the structure of the $Si/Ge(111)-3\times1$ induced by alkali metals.

• Journal of the Korean Magnetics Society
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• v.6 no.5
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• pp.329-333
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• 1996

We have studied the magnetoresistance and the magnetic anisotropy of Cu/(NiFe/Ni/NiFe) metallic multi layers grown on Si(100), Si(111), $4^{\circ}\;tilt-cut\;Si(111)$ or glass substrate. When the multilayer was grown on $4^{\circ}\;tilt-cut\;Si(111)$ with $50\;{\AA}$ of Cu underlayer, an in-plane uniaxial anisotropy was observed. On the other substrates such as Si(100), Si(111) or glass with Cu underlayer, however, no appreciable anisotropy was shown. The multilayer grown with NiFe or Ni underlayer or without underlayer did not show any arnsotropy even on $4^{\circ}\;tilt-cut\;Si(111)$. When $10\;{\AA}$ of NiFe was deposited prior to the Cu underlayer, the anisotropy in Cu/(NiFe/Ni/NiFe) multilayer disappeared.

• Proceeding of EDISON Challenge
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• 2013.04a
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• pp.228-231
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• 2013

In this study, we investigate the electronic and atomic structure of graphene on O-terminated MgO(111) using density functional theory (DFT) calculations. To suggest a possible direction for future band gap engineering of graphene on MgO(111), adsorption of carbon atoms on graphene/MgO(111) is studied by considering the several adsorption sites. Details in adsorption properties of carbon atoms on graphene/MgO(111) are analyzed in terms of energy band structure.