• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 춘계학술발표회요약집
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• pp.168-168
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• 2001

• 대한화장품학회지
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• 제11권1호
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• pp.21-31
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• 1985

폴리옥시에틸렌 도데실 에테르 유도체로 안정화된 헥산 - 물의 유화계에서 소량의 장쇄알칸 및 장쇄알칸올이 유화안정도에 미치는 효과를 비교 검토하였다. 장쇄알칸의 계면장력 및 원심분리에 의한 유화 안정도에 거의 영향을 주지 않았으나 장쇄알칸올은 계면장력을 현저히 저하시켰으며, 원심분리시 coalescence에 의한 유화파괴 방지에 효과적이었다. 그러나 시간 경과에 따른 유화안정도는 장쇄알칸이 장쇄알칸올 보다 더욱 효과적이었고 또 탄화수소쇄 길이가 길어질수록 더욱 효과적이었다. 이러한 것을 유화제를 변경시켰을 경우에도 마찬가지였다. 이것은 장쇄알칸을 첨가함으로써 분산상의 소수결합력을 증대시켜 물에 대한 용해도가 감소되어 분자확산에 의한 유화파괴가 어려워지기 때문이다. 즉 이러한 유화계에서 유화파괴는 coalescence보다는 분자확산에 의해 지배됨을 알 수 있다.

• Structural Engineering and Mechanics
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• 제89권6호
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• pp.557-570
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• 2024

Due to interfacial ageing, chemical action and interfacial damage, the interface debonding may appear in the interfaces of composite laminates. Particularly, the laminates display a side-dependent effect at small scale. In this work, a three-dimensional (3D) and anisotropic thick nanoplate model is proposed to investigate the effects of imperfect interface and nonlocal parameter on the bending deformation, vibrational response and buckling stability of one-dimensional (1D) hexagonal quasicrystal (QC) layered nanoplates. By combining the linear spring model with the transferring matrix method, exact solutions of phonon and phason displacements, phonon and phason stresses of bending deformation, the natural frequencies of vibration and the critical buckling loads of 1D hexagonal QC layered nanoplates are derived with imperfect interfaces and nonlocal effects. Numerical examples are illustrated to demonstrate the effects of the imperfect interface parameter, aspect ratio, thickness, nonlocal parameter, and stacking sequence on the bending deformation, the vibrational response and the critical buckling load of 1D hexagonal QC layered nanoplate. The results indicate that both the interface debonding and nonlocal effect can reduce the stiffness and stability of layered nanoplates. Increasing thickness of QC coatings can enhance the stability of sandwich nanoplates with the perfect interfaces, while it can reduce first and then enhance the stability of sandwich nanoplates with the imperfect interfaces. The biaxial compression easily results in an instability of the QC layered nanoplates compared to uniaxial compression. QC material is suitable for surface layers in layered structures. The mechanical behavior of QC layered nanoplates can be optimized by imposing imperfect interfaces and controlling the stacking sequence artificially. The present solutions are helpful for the various numerical methods, thin nanoplate theories and the optimal design of QC nano-composites in engineering practice with interfacial debonding.

• 한국세라믹학회지
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• 제34권8호
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• pp.908-913
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• 1997

Multilayer NbCxC1-x/Y2O3/Ti were sputter-coated on the alumina substrate, starting with a 0.7 ㎛ thick NbCxC1-x layer grown on substrate, followed by 0.7 ㎛ thick Y2O3 layer and 1 ㎛ thick Ti layer. To find out the optimum conditions for thickness uniformity and adhesion, sputtering works have been done with the variation of sputtering power and Ar pressure. After vacuum annealing at 950℃ and 1000℃, the thermal stability of the NbCxC1-x/Y2O3/Ti coated alumina substrates has been investigated by peel off test. The coating scheme didn't cause any debonded layer after an annealing at 950℃ for 3hrs. However, it was peeled off after annealing at 1000℃ for 3hr. It was found that the thermal stability of Al2O3/NbCxC1-x/Y2O3/Ti coating scheme changed with the NbCxC1-x composition.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2012년도 춘계학술발표대회
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• pp.59.2-59.2
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• 2012

Polymer solar cells utilize bulk heterojunction (BHJ) type photo-active layer in which the electron donating polymer and electron accepting $C_{60}$ derivatives are blended. We found there is significant charge recombination at the interface between the BHJ active layer and electrode. The charge recombination at the interface was effectively reduced by inserting wide band gap inorganic interfacial layer, which resulted in efficiency and stability enhancement of BHJ polymer solar cell.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.771-774
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• 2000

Recently, complex insulation method is used in insulation system for underground power delivery devices. Considering the interfaces which affect stability of insulation system, By modeling interface between Epoxy and Rubber, AC interfacial breakdown properties with variation of many conditions to influence on electrical properties were investigated. In this paper, toughened Epoxy and Silicone rubber were used for materials to make interface .

• Transactions on Electrical and Electronic Materials
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• 제15권6호
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• pp.328-332
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• 2014

Thin film transistors (TFTs) with an amorphous silicon zinc tin oxide (a-2SZTO) channel layer have been fabricated using an RF magnetron sputtering system. The effect of the change of excitation electron on the variation of the total interfacial trap states of a-2SZTO systems was investigated depending on sputtering power, since the interfacial state could be changed by changing sputtering power. It is well known that Si can effectively reduce the generation of the oxygen vacancies. However, The a-2SZTO systems of ZTO doped with 2 wt% Si could be degraded because the Si peripheral electron belonging to a p-orbital affects the amorphous zinc tin oxide (a-ZTO) TFTs of the s-orbital overlap structure. We fabricated amorphous 2 wt% Si-doped ZnSnO (a-2SZTO) TFTs using an RF magnetron sputtering system. The a-2SZTO TFTs show an improvement of the electrical property with increasing power. The a-2SZTO TFTs fabricated at a power of 30 W showed many of the total interfacial trap states. The a-2SZTO TFTs at a power of 30 W showed poor electrical property. However, at 50 W power, the total interfacial trap states showed improvement. In addition, the improved total interfacial states affected the thermal stress of a-2SZTO TFTs. Therefore, a-2SZTO TFTs fabricated at 50 W power showed a relatively small shift of threshold voltage. Similarly, the activation energy of a-2SZTO TFTs fabricated at 50 W power exhibits a relatively large falling rate (0.0475 eV/V) with a relatively high activation energy, which means that the a-2SZTO TFTs fabricated at 50 W power has a relatively lower trap density than other power cases. As a result, the electrical characteristics of a-2SZTO TFTs fabricated at a sputtering power of 50 W are enhanced. The TFTs fabricated by rf sputter should be carefully optimized to provide better stability for a-2SZTO in terms of the sputtering power, which is closely related to the interfacial trap states.

• 한국의류학회지
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• 제19권5호
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• pp.765-773
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• 1995

Effect of interfacial electrical conditions such as, the f potential of PET fiber and u-Fe203 particles, the stability parameter and potential energy of interaction on adhesion of a-Fe903 particles to PET fabric and their removal from the fabric, were investigated as functions of pH, electrolyte and ionic strength. The stability parameter, potential energy of interaction between a-Fe2O3 particles and PET fabric were calculated by using the heterocoagulation theory for a sphere-plate model The adhesion of a-Fe2O3 particles to PET fabric and their removal from PET fabric were carried out by using water bath shaker and Terg-O-Tometer under various solution conditions. The adhesion of a-Fe2O3 particles to the PET fabric and the removal of a-Fe2O3 particles from the PET fabric were biphasic and were maximum and minimum at pH 7~8, respectively. With high pH and polyanion electrolytes in solution, the adhesion of a-Fe2O3 particles to the PET fabric was low but effects of electrolytes on the removal of a-Fe2O3 particles from the PET fabric was small. The adhesion of a-Fe2O3 particles to the PET fabric and the removal of a-Fe2O3 Particles from the PET fabric were biphasic, and were lowest and highest at the ionic strength 1$\times$10-3, respectively. The adhesion of a-Fe2O3 particles to PET fabric was well related with the interfacial electrical conditions; it was negatively correlated with the f potentials of a-Fe2O3 Particles of its absolute value, the stability parameter and the maximum of total potential energy, while, the adhesion was not related with the t potentials of PET fiber itself. Therefore, the primary factor determining the adhesion of a-Fe203 particles to PET fabric may be the stability of dispersed particles caused by the electrical repulsion of particles. The removal of a-Fe203 particles from PET fabric was not related to such interfacial electrical conditions as the t potentials of PET fiber, the stability parameter and the maximum of total potential energy but removal was related to t potential of a-Fe203 particles.

• 한국인쇄학회지
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• 제20권1호
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• pp.65-78
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• 2002

The suspension polymerization of styrene was carried out to obtain the narrow-size distribution of particle by using poly(vinyl alcohol) (PVA) as suspension stabilizer according to the degree of hydrolysis and the molecular weight. The stabilizing properties of suspension are also dependent on the interfacial tension of aqueous solution when PVA is added. When the polymerization process was carried out with low hydrolyzed PVA, it gave single, well-defined particles, while high hydrolyzed PVA gave clusters. The size of particle produced in this study ranged between 5${\mu}{\textrm}{m}$ and 10${\mu}{\textrm}{m}$. The suspending agent, PVA, influences on the drop size and drop stability, When the molecular weight of PVA is increased, the drop size decreases and the drops become more stable toward coalescence. An increase in the PVA concentration decreases the mean drop size and narrows the drop size distribution.

• 한국세라믹학회지
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• 제32권1호
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• pp.120-130
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• 1995

To analyze the mechanical property and the residual stress in functionally gradient materials(FGMs), disctype TZP/Ni-and TZP/SUS304-FGM were hot pressed using powder metallurgy compared with directly bonded materials which were fabricated by the same method. The continuous interface and the microstructure of FGMs were characterized by EPMA, WDS, optical microscope and SEM. By fractography, the fracture behavior of FGMs was mainly influenced by the defects which originated from the fabrication process. And the defectlike cracks in the FGMs induced by the residual stress have been shown to cause failure. This fact has well corresponded to the analysis of the residual stress distribution by Finite Element Method (FEM). The residual stress generated on the interface (between each layer, and matrix and second phase, respectively) were dominantly influenced on the sintering temperature and the material constants. As a consequence, the interfacial stability and the relaxation of residual stress could be obtained through compositional gradient.