• 한국전기전자재료학회논문지
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• 제15권8호
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• pp.678-686
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• 2002

This paper presents the effects of accumulation of surface charges on hydrophobic level and the changes of surface potential decay with various artificial environment treatments on high temperature vulcanized (HTV) silicone rubber used for outdoor insulating material. For this study, the charging apparatus by corona discharge, in which grid electrode was installed between the main corona and ground electrode, was used. From this study, it was found that the accumulation of surface charges above a critical surface potential on silicone insulating materials could lead to the temporary loss of surface hydrophobicity. In addition, corona stress and water absorption stress increase the decay rate of surface charges of HTV silicone rubber, while ultraviolet (UV) stress causes longer decay time. We could conclude that the effects of surface charges on hydrophobicity level and the changes of surface state by various artificial treatments were found through a trend of surface potential decay.

• 전기학회논문지
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• 제59권12호
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• pp.2230-2234
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• 2010

This paper deals with the change of surface potential decay, surface resistivity, contact angle and XPS of ultraviolet-treated PET films. From the experimental results on the surface potential decay of UV degraded-samples, it was found that the accumulation of charge is decreased and the surface potential decay time is shortened. Also, from the result of XPS, it was found that the changes affected by the surface degradation of PET film were caused by the generation of carboxyl groups through the chain decomposition and recombination with oxygen molecules in the air.

• 한국응용곤충학회지
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• 제23권4호
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• pp.242-246
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• 1984

감자 괴경에 타박상을 입혔거나 세균현탁액을 주입했을 때 낮은 water potential(-6.46 bar) 보다 높은 water potential (-6.06 bar)에서 더 쉽게 부패를 초래하였으며, 높은 water potential을 가진 괴경과 낮은 water potential을 가진 괴경 사이에 있어서의 부패의 진전에는 큰 차이를 발견할 수 있었으며, 현탁액의 농도의 종류에 따른 괴경의 연부병의 이병정도는 높은 water potential에서 높았으며, 세균 현탁액 농도의 $ED_{50}$은 높은 water potential에서 $10^{8.5}\;cells/ml$이며 낮은 water potential에 서는 $100^{9.8}\;cells/ml$이었으며, 높은 water potential과 낮은 water potential $ED_{50}$에서는 작은 차이를 인정할 수 있었다. 이 시험에서 감자는 상처나 타박상이 나지 않도록 다루어야 하며 수확후 충분히 건조하여야 오랜 운반과 저장중에 연부병 발생을 크게 줄일 수 있다는 것을 나타낸다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마연구회
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• pp.1-5
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• 2003

This paper presented the effects of accumulation of surface charges on hydrophobicity level and the surface states of silicone polymer used for outdoor insulator treated by ultraviolet irradiation and corona discharge through measuring surface voltage decay of a corona-charged specimen were investigated. The surface resistivity by the method of the surface potential decay was compared with the value by the three electrodes methods. From this study, it was found that the accumulation of surface charges above a critical surface voltage on silicone insulating materials could lead to the temporary loss of surface hydrophobicity. In addtion, uv stress lead to a longer decay time of surface charges. We could conclude that the effects of surface charges on hydrophocity level and the changes of surface state by various artificial treatments were understood through a trend of surface potential decay.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권10호
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• pp.553-558
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• 2000

This paper deals with change of contact angle, surface potential decay, surface resistivity and XPS of water-treated epoxy insulator. From the experimental results on the contact angle was reduced from $74^{\circ}$to $24^{\circ}$ due to the formation of polar hydroxyl groups on surface which was associated with intermolecular reaction between epoxy chains of three-dimensional network structure and water molecules. From the experimental results in the surface potential decay of water treated-samples, it was found that the accumulation of charge is decreased and the surface potential decay time is shortened by the interaction of polar hydroxyl groups induced on the treated surface as the increment of treatment time. The positive charging on the treated surface compared with negative charging is relatively lowered by the induction of polar hydroxyl groups. The surface resistivity was changed from $10^{15}[{\Omega}/cm^2$] to $10^{12}[{\Omega}/cm^2$] caused by water treatment. From XPS, it was found that the changes affected by the surface degradation of epoxy were caused by the generation of carboxyl groups through the chain decomposition and recombination with oxygen molecules in the air.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.323-328
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• 1989

In this paper, we studied the diagnostic method of insulation deterioration for 22.9kV CNCV cable using D.C potential decay component. At first, arbitrary D.C high voltage is appeied the CNCV cable for two minutes and switched off in vacuum. And then D.C potential decay components is measured for ten minutes. It is detecting source for cable insulation deterioration that its gradient is. Provisionally, we decided the criterion voltage and select the high voltage meter and S.W.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1457-1459
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• 2001

This paper deals with the change of surface Potential decay, surface resistivity, contact an91e and XPS of ultraviolet-treated PET films. From the experimental results on the surface Potential decay of UV degraded-samples, it was found that the accumulation of charge is decreased and the surface potential decay time is shortened. Also, from the result of XPS, it was found that the changes affected by the surface degradation of PET film were caused by the generation of carboxyl groups through the chain decomposition and recombination with oxygen molecules in the air.

• 농업과학연구
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• 제38권4호
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• pp.607-612
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• 2011

The occurrence of grape berry shattering and decay is influenced by the pre- and/or postharvest infection of decay organisms and pest. Postharvest infection is associated with physical damage due to rough handling. To control quality loss during storage of table grapes, the effects of slow releasing $SO^2$ pad on storability of 'Rosario Bianco' (Vitis vinifera) and 'Campbell Early' (Vitis labruscana) grapes were examined, respectively. The $SO^2$ concentration in package of tables grapes reached to at about 40 $ug{\cdot}L^{-1}$ after 40 days of treatment and remained more than 80 days above 15 $ug{\cdot}L^{-1}$. Decay was found in untreated 'Rosario Bianco' and 'Campbell Early' grapes at each for 44 and 85 days after storage, but not in $SO^2$ pad treated grapes. The storage potential of grape berries at $0^{\circ}C$ increased 2~3 times depending on cultivar by $SO^2$ pad treatment. The application of $SO^2$ pad is confirmed to be effective on the increase of market potential with minimizing quality loss such as berry shattering and decay.

• 한국인쇄학회지
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• 제11권1호
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• pp.103-122
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• 1993

A cause and counterplan of the increase in dark decay rate of$\varepsilon$-CuPc/PVCz photoreceptor which is consist of the carrier generation layer (CGL) of$\varepsilon$type copper phthalocyanine ($\varepsilon$-CuPc) thin film by an aqueous coating method and the carrier transport layer (CTL) of polyvinylcarbazol (PVCz) by spin coating, are studied in this paper. Electrochemical deposition of CGL was accompanied by an increase in work function of the aluminium substrate during the processes and the enhanced work function 5.3 eV rose above the ionization potential 5.16 eV of $\varepsilon$-CuPc. This resulted in the increased injection of holes from substrate into CGL and a fast dark decay rate. Improved photoreceptor, an electron-transport $\varepsilon$-CuPc/TNF photoreceptor, led to lowing of dark decay rate and increasing of photosensitivity. The carrier generation efficiency (ηg), carrier injection efficiency (ηi) and xerographic gain (G) of the $\varepsilon$-CuPc/TNF photoreceptor were obtained by XTOF method and PIDC.

• 전자공학회논문지 IE
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• 제44권3호
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• pp.6-11
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• 2007

본 연구는 플라즈마 처리한 고분자 복합재료 표면의 접촉각, X-선광전자분광법(XPS) 및 코로나 대전에 의한 표면 정전특성을 분석하여 발생된 화학적 변화와 정전적 특성 변화를 고찰하여 열화 메커니즘을 도출하였다. 플라즈마 처리된 시료의 접촉각 및 표면전위는 표면에 카르복실기 라디칼을 포함하는 다량의 측쇄화가 집중적으로 발생되어 처리시간에 따라 급격한 친수화가 진행되었다. 플라즈마 처리로 인한 화학적 변화에서 표면에 carboxyl 라디칼이 주로 형성되면서 급격히 표면 친수화로 변화하였다. 정전변화를 분석한 전위감쇠 결과에서 미처리 시료는 부극성 표면을 나타내었으나, 친수화 표면은 carboxyl 라디칼(-COO*)을 포함하는 정극성 라디칼로 인해 정극성 표면으로 변화하여 부극성 전하가 빠르게 감소하였다.