• 한국표면공학회지
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• 제41권3호
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• pp.114-120
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• 2008

The pyrolysized carbon xerogel and aerogels were prepared from the sol-gel polymerization of resorcinol-formaldehyde(RF) followed by the dry process under ambient pressure and supercritical carbon dioxide condition respectively. The thermal behaviour of RF polymer xerogel was investigated with TGA analyzer to correspond with the pyrolysis process. The surface properties such as particle size, morphology and the point of zero charge of the pyrolysized porous carbon aerogels were studied for the precious metal catalyst supported media. It was found that the volume of the polymer aerogel decreased because of the significant linear shrinkage and weight loss of polymer gel during the carbonization. The point of zero charge of the carbon aerogel pyrolysized at $1050^{\circ}C$ under inert gas flow was about 10.

• 한국조명전기설비학회지:조명전기설비
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• 제10권3호
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• pp.78-85
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• 1996

표면전위측정 수단을 이용하여 polyethylene terephthalate의 electret 구조를 해명하는 실험을 하였다. 시료에 전극을 증착하므로서 내부의 전하생성과 감쇠를 관측하였다. electret 의 기구에는 hetero charge 와 home charge가 공존하고 있으며 model로 2전하이론을 기반으로 연구하였는데 hetero charge는 쌍극자와 내부의 이온 변위로 되고 hetero charge를 형성하는 것은 외부에서 주입된 전하라고 생각된다.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.902-906
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• 2009

It is found that that the coating N-acetyl cysteine (NAC) on gold surfaces may be used to design the distribution of either gold particle adsorbed to the $TiO_2$ surface or vice versa by adjusting the electrostatic interactions. In this study, we investigated electrostatic properties of the NAC-coated-gold surface and the $TiO_2$ surface. The surface forces between the surfaces were measured as a function of the salt concentration and pH value using the AFM. By applying the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory to the surface forces, the surface potential and charge density of the surfaces were quantitatively acquired for each salt concentration and each pH value. The surface potential and charge density dependence on the salt concentration was explained with the law of mass action, and the pH dependence was with the ionizable groups on the surface.

• 대한전자공학회논문지
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• 제26권8호
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• pp.1187-1196
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• 1989

In this paper, a method for computing the capacitance parameter for a multi-interconnection line in a multilayered dielectric region is presented. The number of interconnection lines and the number of dielectric layers are arbitrary, and the interconnection lines are finite cross section or infinite cross section. The surface of lines and dielectric interface are divided into subsection. The surface charge density of each subsection is a constant step-pulse function for each subsection. After the solution of surface charge density is effected by the method of moments, capacitance parameter is calculated.

• 분석과학
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• 제8권3호
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• pp.383-389
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• 1995

A new approach for the measurement of the surface coverages of monomolecular films fabricated by spontaneous adsorption of thiol compounds on gold is described. It is based on the mass change measurement with EQCM for the reductive electrochemical desorption of thiol in aqueous KOH solution. The results were compared with that of charge calculation during electrochemical desorption. The surface coverage value for eicosanethiol agrees with that obtained by charge calculation of electrochemical reduction as well as that expected from a geometrical model of the compact monolayer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1987-1989
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• 2000

In this paper, electric field distribution of dielectric sphere considering surface or volume resistivity is analysed by the use of rotational symmetric charge simulation method. We applied three methods such as ${\alpha},{\beta}$ modified $\beta$ method to check electric field calculation error. We find f method and modified $\beta$ method are suitable to simulate volume and surface resistivity respectively.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.2855-2860
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• 2012

The coating N-acetyl cysteine (NAC) on gold surfaces may be used to design the distribution of either gold particle adsorbed to the $ZrO_2$ surface or vice versa by adjusting the electrostatic interactions. In this study, it was performed to find out electrostatic properties of the NAC-coated-gold surface and the $ZrO_2$ surface. The surface forces between the surfaces were measured as a function of the salt concentration and pH value using the AFM. By applying the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory to the surface forces, the surface potential and charge density of the surfaces were quantitatively acquired for each salt concentration and each pH value. The dependence of the potential and charge density on the concentration was explained with the law of mass action, and the pH dependence was with the ionizable groups on the surface.

• 대한전자공학회논문지
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• 제27권7호
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• pp.1033-1041
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• 1990

In this paper, under pinch-off conditions, the gate-drain breakdown voltage characteristics of GaAs Power MESFET's as a function of device parameters such as channel thickness, doping concentration, gate length etc. are analyzed. Using the Green's function, the gate ionic charge induced by the depleted channel ionic charge is calculated. The impact ionization integral by avalanche multiplication between gate and drain is used to investigate breakdown phenomena. Especially, the localized excess surface charge effect as well as the uniform surface charge effect on breakdown voltage is considered.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.571-573
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• 2007

It is known that the main source of the area image sticking is the ion charge adsorption on the alignment layer. We found out that the adsorption of the ion charge of the liquid crystal in the cell was physisorption, which takes place between all molecules on any surface providing the adsorption force is small.

• 한국안전학회지
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• 제18권3호
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• pp.60-63
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• 2003

For the increase the charge stability of teflon electrets for used at uncomfortable industrial circumstances with high temperature or humidity, We made an investigation into double layer effect of teflon electrets. Teflon AF film was spincoated on FEP film and then the charge storage property of AF/FEP dual film was investigated to be compared with FEP film. It was found that the AF/FEP dual film has higher surface potential than FEP film on the repeated charging and annealing process. It seems that AF/FEP dual film has higher thermal stability than FEP film through TSC measurement. If the investigations of the double layer effect of Teflon film carried out more closely with it's molecular structures and surface conditions, it may be effectively improved the stability of charge storage.