• 한국응용과학기술학회지
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• 제19권2호
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• pp.86-96
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• 2002

Oligomer type anionic surfactants(RmM-Na or RmD-Na} were synthesized from $C_{8}{\sim}C_{16}$ long chain alkylvinylether and maleic anhydride (or maleic diethylether). And also their fluorescent anionic surfactants (RmF- Na) were obtained from alkali neutralization which opens the lactone ring of the condensing materials produced by maleic anhydride alkylvinylether copolymer and 3-aminophenol. The measurement results for the surface active properties of water soluble oligomer type anionic surfactants with fluorescent structure (RmF-Na) exhibited a remarkable surface tension lowing property, foam breaking property, and a ernulsing power.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2006년도 공동학술대회 논문집
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• pp.17-22
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• 2006

Shear modulus is directly linked to material's stiffness and is one of the most critical engineering parameters. Seismically, shear-wave velocity (Vs) is its best indicator. Although methods like refraction, down-hole, and cross-hole shear-wave surveys can be used, they are generally known to be tougher than any other seismic methods in field operation, data analysis, and overall cost. On the other hand, surface waves, commonly known as ground roll, are always generated in all seismic surveys with the strongest energy, and their propagation velocities are mainly determined by Vs of the medium. Furthermore, sampling depth of a particular frequency component of surface waves is in direct proportion to its wavelength and this property makes the surface wave velocity frequency dependent, i.e., dispersive. The multichannel analysis of surface waves (MASW) method tries to utilize this dispersion property of surface waves for the purpose of Vs profiling in 1-D (depth) or 2-D (depth and surface location) format. The active MASW method generates surface waves actively by using an impact source like sledgehammer, whereas the passive method utilizes those generated passively by cultural (e.g., traffic) or natural (e.g., thunder and tidal motion) activities. Investigation depth is usually shallower than 30 m with the active method, whereas it can reach a few hundred meters with the passive method. Overall procedures with both methods are briefly described.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2011년도 춘계학술대회 및 Fine pattern PCB 표면 처리 기술 워크샵
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• pp.82-82
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• 2011

• Journal of Electrochemical Science and Technology
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• 제1권2호
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• pp.112-116
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• 2010

Fractal property of the passivated steel surface was investigated on the basis of scaling analysis with a special focus on its relationship with corrosion resistance. For this purpose, the surface of stainless steel was intentionally oxidized under a variety of passivation conditions and its scaling property was analyzed by a triangulation method. The morphology of the passivated steel surface was satisfactorily evaluated with fractal dimension. From the chronoamperometry and impedance measurement, it proved that lower fractal dimension leads to more enhanced corrosion resistance. The higher passivity of the steel surface with lower fractal dimension was discussed in terms of active area and structural imperfection.

• E2M - 전기 전자와 첨단 소재
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• 제10권7호
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• pp.719-726
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• 1997

This research was conducted to analyze the change of surface tension, viscosity, streaming current and conductivity of transformer oil when it were injected with the interface active substances.(anionic:S-111, cationic:S-121, amphoteric:S-131) The changes properties of the surface tension and viscosity of the oil which were injected with the interface active substances were divided into the changes area and the minimum reduction area. The surface tension and viscosity of the oil which were injected with three different kinds of interface active substances showed remarkable change at the point where the concentration of the substance in anionic, in cationic and in amphoteric were 100[ppm], 10[ppm] and 1[ppm] respectively. The streaming current and conductivity of the same sample oil were also changed at the same densities of the surface tension and viscosity. For this factor, it was possibile for us to interpret the mechanism of the streaming current and conductivity. Therefore the interface active substances of the three kinds were injected into the oil within the limit of optimal volume, prevention effects of electrification were showed more excellence than unmixed insulating oil.

• Journal of Electrochemical Science and Technology
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• 제9권4호
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• pp.330-338
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• 2018

The adhesion strength as well as the electrochemical properties of $LiNi_{0.4}Mn_{0.4}Co_{0.2}O_2$ electrodes containing various conductive carbons (CC) such as fiber-like carbon, vapor-grown carbon fiber, carbon nanotubes, particle-like carbon, Super P, and Ketjen black is compared. The morphological properties is investigated using scanning electron microscope to reveal the interaction between the different CC and the active material. The surface and interfacial cutting analysis system is also used to measure the adhesion strength between the aluminum current collector and the composite film, and the adhesion strength between the active material and the CC of the electrodes. The results obtained from the measured adhesion strength points to the fact that the structure and the particle size of CC additives have tremendous influence on the binding property of the composite electrodes, and this in turn affects the electrochemical property of the configured electrodes.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1121-1124
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• 2004

Aging test to estimate life property of polymer insulator is executed through several international standard such as IEC 61109 and CEA tracking wheel test, but is not getting clear conclusion yet. There are two methods in the diagnosis method of polymer insulator such as off-line and on-line. The diagnosis methods in off-line are external condition analysis by the eye, contaminant analysis on surface, surface analysis, pollution withstand voltage test, power frequency flashover voltage test, lightning impulse flashover test, tensile fracture load test and flexural load test. The diagnosis methods in off-line most are the method for virgin and last aged sample. However, the diagnosis method in on-line is method that can be evaluate sample state as progressing continuously aging test in beginning, The diagnosis method in on-line is arranged as following: leakage current measurement, electric field, surface state investigation, thermal image, emitting light measurement and then so. In this paper, the tracking performance of polymer insulator with salt solution which is added surface active agent. The diagnosis of insulator sample has been analyzed by leakage current and visual examination.

• 한국의류산업학회지
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• 제14권4호
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• pp.677-683
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• 2012

1-octanethiol and vinyl acetate telomers ($R_8S$-nVAc) were synthesized and hydrolyzed with sodium hydroxide subsequently, 1.2-epoxyhexane was then introduced to the telomers. In addition, we prepared cotelomers of multi-alkylated nonionic surfactants with a molecular structure of xRnMA-yVA (x; hydrophobic group, y; hydrophilic group, MA; methacrylic ester, VA; vinyl alcohol, R; and alkyl group) and cross-linked with sodium tetraborate decahydrate. Their active surface properties were investigated by several techniques such as surface tension, foaming property, and emulsification power measurements. The surface tension of $R_8S$-8.8VA decreased without the introduction of 1.2-Epoxy hexane, and the degree of emulsification and foaming abilities of $R_8S$-8.8VA increased without the introduction of 1.2-Epoxy hexane. However, the differences were insignificant. The epoxy groups were attached to a $R_8S$-8.8VA cotelomer with a limited variation of the active surface properties. The surface tension of $1.1R_6MA$-8.8VA decreased after cross-linking subsequently, the degree of emulsification and foaming abilities of $1.1R_6MA$-8.8VA increased after cross-linking. However, there was no clear difference between them. The B-O bonds were attached to a $1.1R_6MA$-8.8VA cotelomer with a limited variation of the active surface properties.

• 한국표면공학회지
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• 제32권1호
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• pp.61-66
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• 1999

The Spin-dependent tunneling magnetoresistance (TMR) effect was observed in $NiFe/Al_2O_3$/Co thin films. The samples were prepared by magnetron sputtering in a system with a base pressure of $3\times10^{-6}$Torr. the insulating $Al_2O_3$layer was prepared by r.f. plasma oxydation method of a metallic Al layer. The ferromagnetic and insulating layers were deposited through metallic masks to produce the cross pattern form. The junction has an active area of $0.3\times0.3\textrm{mm}^2$ and the $Al_2O_3$layer is deposited through a circular mask with a diameter of 1mm. It is very important that insulating layer is formed very thinly and uniformly in tunneling junction. The ferromagnetic layer was fabricated in optimum conditions and the surface of that was very flat, which was observed by AFM. Tunneling junction was confirmed through nonlinear I-V curve. $NiFe/Al_2O_3$/Co junction was observed for magnetization behavior and magnetoresistance property and magnetoresistance property is dependent on magnetization behavior and magnetoresistance property and magnetoresistance property is dependent on magnetization behavior of t재 ferromagnetic layer. The maximum magnetoresistance ratio was about 6.5%.

• Macromolecular Research
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• 제17권3호
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• pp.174-180
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• 2009

Chemical modification of titanium/titanium oxide (Ti/$TiO_2$) substrates has recently gained a great deal of attention because of the applications of Ti/$TiO_2$-based materials to biomedical areas. The reported modification methods generally involve passive coating of Ti/$TiO_2$ substrates with protein-resistant materials, and poly(ethylene glycol) (PEG) has proven advantageous for bestowing a nonbiofouling property on the surface of Ti/$TiO_2$. However, the wider applications of Ti/$TiO_2$ based materials to biomedical areas will require the introduction of biologically active moieties onto Ti/$TiO_2$, in addition to nonbiofouling property. In this work, we therefore utilized surface-initiated polymerization to coat the Ti/$TiO_2$ substrates with polymers presenting the nonbiofouling PEG moiety and subsequently conjugated biologically active compounds to the PEG-presenting, polymeric films. Specifically, a Ti/$TiO_2$ surface was chemically modified to present an initiator for atom transfer radical polymerization, and poly(ethylene glycol) methacrylate (pEGMA) was polymerized from the surface. After activation of hydroxyl groups of poly(pEGMA) (pPEGMA) with N,N'-disuccinimidyl carbonate, biotin, a model compound, was conjugated to the pPEGMA films. The reactions were confirmed by infrared spectroscopy, X-ray photoelectron spectroscopy, contact angle goniometry, and ellipsometry. The biospecific binding of target proteins was also utilized to generate micropatterns of proteins on the Ti/$TiO_2$ surface.