• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.500-504
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• 2010

The PU-g-MWNTs/PU film was synthesized by simple blending method to fabricate composites which have excellent mechanical and electrical properties. PU-g-MWNTs based composite revealed much enhanced dispersity than pristine MWNTs composite because of interfacial interaction related with interfacial compatibility between polymer matrix and PU on the MWNTs surface. The electro-conductivity of composite was measured as a function of PU-g-MWNTs concentration. The results were correlated with percolation threshold theory. As a result, the critical concentration and exponent of electro-conductivity behavior was equal to 0.78 wt% and 0.945.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.4
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• pp.347-353
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• 2008

Reflected light can be decomposed into specular and diffuse components according to the light reflectance theory and experiments. The specular component appears in smooth surfaces mainly, while the diffuse one is visible in rough surfaces mostly. Therefore, each component can be used in forming their correlations to a surface roughness. However, they cannot represent the whole surface roughness seamlessly, because each formulation is merely validated in their available surface roughness regions. To solve this problem, new approaches to properly blend two light components in all regions are proposed in this paper. First is the weighting function method that a blending zone and rate can be flexibly adjusted, and second is the neural network method based on the learning from the measurement data. Simulations based on the light reflectance theory were conducted to examine its performance, and then experiments conducted to prove the enhancement of the measurement accuracy and reliability through the whole surface roughness regions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05d
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• pp.53-56
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• 2003

Blending effects for generating a pretilt angle in nematic liquid crystal (NLC) with negative dielectric anisotropy on the blended polyimide (PI) of homeotropic and homogeneous alignment surface were studied. Also, we investigated the EO performances for the advanced VA-$\pi$ cell using this homeotropic blended PI surface. A many decrease of tilt angle on the polymer surface to blend homeotropic PI and homogeneous PI with side chain type was measured, and the tilt angle decreased as blended ratio and rubbing strength increase. The blended effects for generating a pretilt angle were clearly observed, and the many decrease of tilt angle can be achieved by using the blended PI surface. The electro-optical (EO) characteristics using the advanced VA-$\pi$ cell using the homeotropic blended PI surface than that of conventional VA cell can be improved. We suggest that the developed advanced VA-$\pi$ cell on a homeotropic blended PI surface is a promising technique for the achievement of a fast response time, and a high contrast ratio.

• Journal of Environmental Science International
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• v.19 no.9
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• pp.1161-1167
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• 2010

The effects of addition of non degradable polymers, polystyrene (PS) and poly(methyl methacrylate) (PMMA) on the rate of enzymatic degradation of biodegradable poly(l-lactide) (PLLA) have been studied in term of surface structure. Since a component in multicomponent polymeric system has shown surface enrichment, PS and PMMA which have lower surface energy than PLLA were selected as a minor blend component (5 wt%). Enzymatic degradation was carried out at $37^{\circ}C$ and pH 8.5 in the aqueous solution of Proteinase K. Two blend systems, partially miscible (PS/PLLA) and immiscible (PMMA/PLLA), showed the surface enrichment of 4 and 2 times of PS and PMMA, respectively. From the weight loss profile data, the slow degradation rate of both blend films was observed. This indicates that PS or PMMA domains which exist at surface act as a retardant of enzymatic attack.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.530-533
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• 2002

Blending effects for generating a pretilt angle in nematic liquid crystal (NLC) with negative dielectric anisotropy on the blended polyimide (PI) of homeotropic and homogeneous alignment surface were studied. Also, we investigated the EO performances for the advanced VA-$\pi$ cell using this homeotropic blended PI surface. A many decrease of tilt angle on the polymer surface to blend homeotropic PI and homogeneous PI with side chain type was measured, and the tilt angle decreased as blended ratio and rubbing strength increase. The blended effects for generating a pretilt angle were clearly observed, and the many decrease of tilt angle can be achieved by using the blended PI surface. The electro-optical (EO) characteristics using the advanced VA-$\pi$ cell using the homeotropic blended PI surface than that of conventional VA cell can be improved. We suggest that the developed advanced VA-$\pi$ cell on a homeotropic blended PI surface is a promising technique for the achievement of a fast response time, and a high contrast ratio.

• Journal of Powder Materials
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• v.21 no.3
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• pp.179-184
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• 2014

In this study, we prepare polymer solar cells incorporating organic ligand-modified Ag nanoparticles (O-AgNPs) highly dispersed in the P3HT:PCBM layer. Ag nanoparticles decorated with water-dispersible ligands (WAgNPs) were also utilized as a control sample. The existence of the ligands on the Ag surface was confirmed by FT-IR spectra. Metal nanoparticles with different surface chemistries exhibited different dispersion tendencies. O-AgNPs were highly dispersed even at high concentrations, whereas W-AgNPs exhibited significant aggregation in the polymer layer. Both dispersion and blending concentration of the Ag nanoparticles in P3HT:PCBM matrix had critical effects on the device performance as well as light absorption. The significant changes in short-circuit current density ($J_{SC}$) of the solar cells seemed to be related to the change in the polymer morphology according to the concentration of AgNPs introduced. These findings suggested the importance of uniform dispersion of plasmonic metal nanoparticles and their blending concentration conditions in order to boost the solar cell performance.

• Journal of Electrochemical Science and Technology
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• v.10 no.3
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• pp.284-293
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• 2019

Herein, we report an electrode surface with a hierarchical assembly of wild-type M13 virus nanofibers (M13) to nucleate the AuPt alloy nanostructures by electrodeposition. M13 was pulled on the electrode surface to produce a virus film, and then a layer of sol-gel matrix (SSG) was wrapped over the surface to protect the film, thereby a bio-template was constructed. Blending of metal binding domains of M13 and amine groups of the SSG of the bio-template were effectively nucleate and directed the growth of nanostructures (NSs) such as Au, Pt and AuPt alloy onto the modified electrode surface by electrodeposition. An electrocatalytic activity of the modified electrode toward methanol oxidation in alkaline medium was investigated and found an enhanced mass activity ($534mA/mg_{Pt}$) relative to its controlled experiments. This bio-templated growth of NSs with precise composition could expedite the intention of new alloy materials with tuneable properties and will have efficacy in green energy, catalytic, and energy storage applications.

• Journal of the Korean Wood Science and Technology
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• v.27 no.3
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• pp.73-81
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• 1999

This paper was intended to evaluate the effect of the blending condition of pigments on the packing structure of coating color and the interaction between pigments and latices on the optical and interior properties of coated paper. It has been studied many ways to modify the coating structure to induce the interaction among coating components as followings ; 1) to use dispersant for pigment, 2) to control the charge density and the type of surface charge of latex, 3) to support the water retention by adding water retention agent or flow modifier. This paper was performed through the introduction of interaction between pigments which were two kinds of clays and one precipitated calcium carbonate(PCC) and ionic latices of which anionic and amphoteric respectively under the certain blending condition of pigments where their blending ratio of clays to calcium carbonate was 70pph to 30pph. The reason is that packing volume of pigments was highest in that region and thixotropical behavior appears in measuring rheology of coating color. We measured the properties of coating color, interaction with pigments and latex, and properties of coated paper and its printability. As a results, we could find out that amphoteric latex had a great influence on the interaction with pigments, especially clays, no matter what grade and also affected the coating structure significantly in case that this blending condition was 70(clays) to 30(PCC). It produced a powerful effect on the forming of bulky and smooth coating structure and in turn improved the printability of coated paper.

• Macromolecular Research
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• v.17 no.4
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• pp.232-239
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• 2009

This paper describes the simple nanopatterning of proteins on polyelectrolyte surfaces using microcontact printing with a nanopatternable, hydrophilic composite nanomold. The composite nanomold was easily fabricated by blending two UV-curable materials composed of Norland Optical Adhesives(NOA) 63 and poly(ethylene glycol) dimethacrylate(PEG-DMA). NOA 63 provided stable nanostructure formation and PEG-DMA induced high wettability of proteins in the nanomold. Using the composite mold and functionalized surface with polyelectrolytes, the fluorescent, isothiocyanate-tagged, bovine serum albumin(FITC-BSA) was successfully patterned with 8 nm height and 500 nm width. To confirm the feasibility of the protein assay on a nanoscale, a glycoprotein-lectin assay was successfully demonstrated as a model system. As expected, the lectins correctly recognized the nano-patterned glycoproteins such as chicken ovalbumin. The simple preparation of composite nanomold and functionalized surface with a universal platform can be applied to various biomolecules such as DNA, proteins, carbohydrates, and other biomolecules on a nanoscale.

• Journal of the Korea Computer Graphics Society
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• v.12 no.1
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• pp.1-7
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• 2006

본 논문에서는 다양체 (manifold) 구조와 스칼라 변위함수 (scalar displacement function)에 기반한 새로운 변위곡면 (displaced surface)의 표현 기법을 제안한다. 변위곡면은 제어메쉬 (control mesh)의 각 정점에서 변위된 국소적 패치들 (displaced local patches)을 블렌딩 (blending)함으로써 생성된다. 제안된 변위곡면은 점 군 (point cloud)의 형태로 주어진 기하학적 모델을 근사하기 위해서 사용된다. 점 군의 데이터로터 제어메쉬가 생성되고, 점 군의 점들이 제어메쉬의 국소적 패치들 (local patches)에 사영 (projection)되어 각 패치들로 부터의 스칼라 변위함수가 구해지고, 이러한 변위함수들을 최적화 하여 높은 정밀도를 갖는 최종적인 곡면을 생성된다. 점 군의 형태로 주어진 다양한 모델에 대한 실험 결과를 통해서 제안된 근사기법의 효율성과 정밀도가 입증된다. 본 논문에서 제안된 표현기법은 다 단계 (multi-level) 변위함수를 통해 다중해상도 표현 (multi-resolution representations)과 골격기반 형상변형 (skeleton-driven deformation)등과 같은 다양한 응용들에 효율적으로 사용된다.