• 한국전기전자재료학회논문지
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• 제30권2호
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• pp.86-90
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• 2017

This work reports the phase-change behavior and thermal stability of doped GeSbTe/GeSbTe bilayers. We prepared the bilayers using RF sputtering, and annealed them at annealing temperature ranging from $100^{\circ}C$ to $400^{\circ}C$. The sheet resistance of the bilayer decreased and saturated with increasing annealing temperature, and the saturated value was close to that of pure GeSbTe film. The surface of the bilayer roughened at $400^{\circ}C$, which corresponds to the surface roughening of doped GeSbTe film. Mixed phases of face-centered cubic and hexagonal close-packed crystalline structures were identified in the bilayers annealed at elevated temperature. These results indicate that the phase-change behavior of the bilayer depends on the concurrent phase-transitions of the two GeSbTe-based films. The dopants in the doped GeSbTe film were diffused out at annealing temperatures of $300^{\circ}C$ or higher, which implies that the thermal stability of the bilayer should be considered for its application in phase-change electronic devices.

• 대한전기학회논문지
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• 제45권2호
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• pp.242-248
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• 1996

The properties of TiN/TiSi$_{2}$ bilayer formed by a rapid thermal annealing is investigated when thin SiO$_{2}$ film exists at the Ti-Si interface. The competitive reaction for the TiN/TiSi_2 bilayer occurs above 600 .deg. C. The thickness of the TiSi$_{2}$ layer decreases with increasing SiO$_{2}$ film thickness and also decreases with increasing anneal temperture When the competitive reaction for the TiN/TiSi$_{2}$ bilayer is occured by rapid thermal annealing, the composition of TiN layer represents TiN$_{x}$O$_{y}$ due to the SiO$_{2}$ layer at the Ti-Si interface but the structures of the TiN and TiSi$_{2}$ layers were not changed.d.d.

• 한국재료학회지
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• 제32권1호
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• pp.51-55
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• 2022

Generally, Au electrodes are the preferred top metal electrodes in most perovskite solar cells (PSCs) because of their appropriate work function for hole transportation and their resistance to metal-halide formation. However, for the commercialization of PSCs, the development of alternative metal electrodes for Au is essential to decrease their fabrication cost. Ag electrodes are considered one of the most suitable alternatives for Au electrodes because they are relatively cheaper and can provide the necessary stability for oxidation. However, Ag electrodes require an aging-induced recovery process and react with halides from perovskite layers. Herein, we propose a bilayer Au/Ag electrode to overcome the limitations of single Au and Ag metal electrodes. The performance of PSCs based on bilayer electrodes is comparable to that of PSCs with Au electrodes. Furthermore, by using the bilayer electrode, we can eliminate the aging process, normally an essential process for Ag electrodes. This study not only demonstrates an effective method to substitute for expensive Au electrodes but also provides a possibility to overcome the limitations of Ag electrodes.

• Archives of Pharmacal Research
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• 제13권1호
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• pp.64-68
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• 1990

The stabilization effect of .alpha.-tocopherol incorporated into liposomal phospholipid membrane was investigated by fluorospectrophotometry and UV-visible spectretarded by the presence of .alpha.-tocopherol in the bilayer of liposomal phospholipid membrane relative to cholesterol-containing liposomes and pure phospholipid liposomes. .alpha.-tocopherol-containing liposomes prolonged the oxidation of liposomes-embedded heme as those of cholesterol-containing liposomes and pure phospholipid liposomes. Thus .alpha.-tocopherol-containing liposomes may be useful for the carrier systems of nutrients and drugs to phospholipid bilayer and stabilized liposomes.

• 한국막학회:학술대회논문집
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• 한국막학회 1992년도 추계 총회 및 학술발표회
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• pp.1-4
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• 1992

생체막은 많은 생물학적인 과정에서 중요한 역할을 차지한다. 막의 주된 성분은 지질과 단백질이고, 막의 기본적인 구조는 2개의 지질분자가 소수성기를 안쪽으로 서로 마주보며 이차원으로 배열된 Bilayer구조이다. 막의 두께는 약 50A 전후로 지구상에 존재하는 막중에서 가장 얇은 막이라 할 수 있다. 막의기능성은 근본적으로 이 Bilayer구조특성에서 나온다고 할 수 있다. 생체막의 대표적인 물질로 Lecithin은 Phosphatidyl Choline을 친수성기로, 2개의 긴 알킬체인이 소수성영역으로 된 양친매성 화합물이다.

• Journal of the Korean Physical Society
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• 제73권12호
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• pp.1899-1903
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• 2018

The effects of introducing hybrid lipids to a lipid bilayer containing saturated and unsaturated lipids immersed in water were studied. The lipid and water molecules were modeled as coarse-grained particles. All particles were simulated by using the dissipative particle dynamics method. The results showed that the hybrid lipids accumulated at the interface between the saturated and the unsaturated lipid domains. The relation between the hybrid lipid concentration and the equilibrium domain size was obtained. Moreover, the sizes of the simulated lipid domains are consistent with that given by the lipid raft definition.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.2087-2092
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• 2009

We performed molecular dynamics simulations on dimyristoylphosphatidylcholine lipid bilayer with 50 mol% halothane. The structural properties, electron density profile, segmental order parameter of acyl chains, headgroup orientation distribution, water dipole orientation distribution, have been examined. Overall the effects of the halothane molecules on structural properties of DMPC lipid bilayer were found to be small. The electron density profiles, the segmental order parameter, the headgroup orientation, the water dipole orientation were not affected significantly by the halothane molecules. Pressure tensor calculations shows that the lateral pressure increases at the hydrocarbon tail region and the headgroup region, and decreases at the water-headgroup interfacial region.

• 한국응용과학기술학회지
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• 제13권3호
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• pp.43-49
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• 1996

Metachromatic properties of admixture of thionine and methylene blue(MB) in aqueous solution and phospholipid bilayer membrane have been studied by absorption spectroscopy. When thionine and MB were mixed, new coaggregate has been formed because of MB was redistributed to thionine aggregate. In phosphlipid bilayer membrane system, the highly concentrated thionine was easily formed the coaggregation with MB moiety independent of MB concentration, and absorption band of admixture were more transferred to short wavelength than aqueous system. In monomeric thionine concentration, the coaggregation band was observed at the middle wavelength between the site of monomeric thionine and the site of dimeric MB in the presence of lipid bilayer membrane.

• 한국세라믹학회지
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• 제36권6호
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• pp.604-610
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• 1999

Silicide layer structures and morphology degradation of the surface and interface of the silicide layers for he Co/refractory metal bilayer sputter-deposited on the P-doped polycrystalline Si substrate and subjected to rapid thermal annealing were investigated and compared with those on the single Si substrate. The CoSi-CoSi2 phase transition temperature is lower an morphology degradation of the silcide layer occurs more severely for the Co/refractorymetal bilayer on the P-doped polycrystalline Si substrate than on the single Si substrate. Also the final layer structure and the morphology of the films after silicidation annealing was found to depend strongly upon the interlayer metal. The layer structure after silicidation annealing of Co/Hf/doped-poly Si is Co-Hf alloy/polycrystalline CoSi2/poly Si substrate while that of Co/Nb is polycrystalline CoSi2/NbSi2/polycrystalline CoSi2/poly Si.

• Applied Microscopy
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• 제42권4호
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• pp.218-222
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• 2012

Modern aberration-corrected transmission electron microscope (TEM) with appropriate electron beam energy is able to achieve atomic resolution imaging of single and bilayer graphene sheets. Especially, atomic configuration of bilayer graphene with a rotation angle can be identified from the direct imaging and phase reconstructed imaging since atomic resolution Moir$\acute{e}$ pattern can be obtained successfully at atomic scale using an aberration-corrected TEM. This study boosts a reliable stacking order analysis, which is required for synthesized or artificially prepared multilayer graphene, and lets graphene researchers utilize the information of atomic configuration of stacked graphene layers readily.