• 상하수도학회지
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• 제18권3호
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• pp.307-311
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• 2004

The objective of this work is to evaluate the hypothesis that a good technique for supplying oxygen to the saturated zone in the presence of light nonaqueous phase liquid (LNAPL) pool contamination at the water table is to pass air through the unsaturated zone above the pool. This hypothesis was evaluated in experimental studies performed using a bench-scale, sand-tank reactor, Steady-state abiotic experiments in the sand-tank reactor with air flowing through the reactor headspace demonstrated that oxygen supply through the water table interface into the saturated zone was enhanced when an LNAPL (dodecane) pool was present at the water table. These experimental results confirmed the hypothesis that an LNAPL pool can serve as a high concentration oxygen source to the oxygen-limited area beneath the pool and, as a result, enhance the in situ biodegradation rate.

• 한국응용과학기술학회지
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• 제28권3호
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• pp.329-334
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• 2011

The electrochemical performances of an asymmetric hybrid capacitor were investigated using $LiFePO_4$ as the positive electrode and active carbon fibers(ACF) as the negative electrode. The electrochemical behaviors of a nonaqueous hybrid capacitor were characterized by constant current charge/discharge test. The specific capacitance using $LiFePO_4$/ACF electrode turned out to be $0.87F/cm^2$ and the unit cell showed excellent cycling performance. This hybrid capacitor was able to deliver a specific energy as high as 178 Wh/kg at a specific power of 1,068 W/kg.

• 대한화학회지
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• 제15권4호
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• pp.211-217
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• 1971

The theory of solubility proposed by Jhon and Kihara has been tested and applied to various systems. In the present paper, the systems are the solubilities of gases such as $Ar,\;H_2,\;N_2,\;O_2,\;CO_2,\;CH_4,\;and\;C_2H_6$ in liquid benzene and carbon disulfide, those of solids iodine and naphthalene in the nonaqueous solvents, and those of gases $H_2,\;N_2,\;O_2,\;Ar,\;CH_4,\;and\;C_2H_4$ in the electrolyte solutions. The theoretical values of solubilities are in good agreement with the experimental data in the literature.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.115-118
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• 2006

The partitioning tracer method has been studied as an alternative method for characterizing aquifers contaminated by nonaqueous phase liquids (NAPLs). Accurate partition coefficients of tracers partitioning between NAPL and water are needed to improve the reliability of the partitioning tracer method. In this research, partition coefficients of alcohol tracers partitioning between benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds and water are estimated from using the approach of equivalent alkane carbon number (EACN). General agreement was observed in between the measured and estimated partition coefficients. Based on these results we can verify that the EACN approach is suitable for estimating the partition coefficient.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.255-265
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• 2006

The oxidation of hydrazobenzene by molecular oxygen in the polar solvent methanol is catalysed by a Schiff's base complex Co(3MeOsalen) which is a synthetic oxygen carrier. The products are trans-azobenzene and water. The rate of the reaction has been studied spectrophotometrically and the rate law established. A mechanism involving a ternary complex of catalyst, hydrazobenzene and molecular oxygen has been proposed. The kinetic studies show that a ternary complex $CoL{\cdot}H_2AB{\cdot}O_2$ is involved in the rate determining step. The reactions are summarised in a catalytic cycle. The kinetic data suggest that a ternary complex involving Co(3MeOsalen), triphenyl-phosphine and molecular oxygen is catalytically acive species but at higher triphenylphosphine concentrations the catalyst becomes inactive. The destruction of the catalytic activity could be due to the catalyst becoming coordinated with triphenyl phosphine at both z axis sites of the complex e.g. Co (3MeOsalen)$(PPh_3)_2$.

• 대한화학회지
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• 제18권5호
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• pp.341-353
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• 1974

Triphenylphosphine phenylimide의 비수용액에서의 전기화학적인 환원반응을 polarography, cyclic voltammetry, controlled-potential coulometry 및 electron spin resonance 법을 써서 고찰하였다. 이 유기인화합물은 one-electon transfer에 따라서 anion radical이 형성되나 순간일 뿐이고 protonation과 재차 one-electon reduction 결과 인과 질소사이의 이중결합이 끊어진다. 그 결과 아닐린이 주요 반응생성물로서 발견되었다. 또 한편 동반하는 화학반응결과 생긴 주산물의 하나인 triphenylposphine oxide의 환원결과 인과 페닐 사이의 단일결합이 끊어지는 것도 관찰할 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 춘계학술대회 논문집
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• pp.67-70
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• 1994

On this study, we fabricated humudity sensor with polyimide thin film from the nonaqueous emulsion by the electrophoretic deposition as a function of film thickness. then evaluated performance of the sensor with increasing relative humidity if constant temperature constant humidity chamber, which is electronically controlled. we designed upper electrode of the sensor to brush type to make moisture particles permeate into the polymer bulk. sensing properties of the sensor on % RH shows proportion on the low %RH. Fer the 30V-30S- 200$^{\circ}C$ sample, percentage changing of capacitance on from 30 %RH to 90 %RH is 45.8 %, and increasing rate per 1 % RH of capacitance is 11.25 pF

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 춘계학술대회 논문집
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• pp.103-107
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• 1994

An experimental study was carried out to investigate the fabrication process and electrical breakdown of electrodeposted polyimide film from nonaqueous emulsion onto metal electrode surface. The thickness of imide film control led by the deposition voltage and time are proportional to the voltage or time. From the results, yeilds is proportional to the total elctrical charge flow through the electrode. When electrophoretic deposition voltage is 30 [V] deposition time is 30 sec, 40 sec, 50 sec, then the thickness of the films are 2.13 $\mu\textrm{m}$, 2.69 $\mu\textrm{m}$, 3.16 $\mu\textrm{m}$, 3.94 $\mu\textrm{m}$, respectively Electrical breakdown voltage of polyimide thin film shows very high. As film thicknes increase, the breakdown voltage are increased, but are net directly proprotional to thickness of the film.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.372-372
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• 2007

Titanium oxide nanotube arrays were fabricated by the anodization of pure titanium thin film deposited at $500^{\circ}C$ on silicon substrates. The titania nanotubes were grown by anodization in nonaqueous-base electrolytes at different potentials between 5 V and 30 V. $TiO_2$ nanotube array with a small pore diameter of 40 nm and long titanium oxide layer of $4\;{\mu}m$ was obtained. The $TiO_2$ nanotube array was used as a porous electrode for quartz crystal microbalance (QCM). Nanoporous morphology of electrode will increase the sensitivity of microbalance.

• Bulletin of the Korean Chemical Society
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• 제20권9호
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• pp.1049-1055
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• 1999

Electrochemical oxidation of silicon (p-type Si(100)) at room temperature in ethylene glycol and in aqueous solutions has been performed by applying constant low current densities for the preparation of thin SiO2 layers. In-situ ac impedance spectroscopic methods have been employed to characterize the interfaces of electrolyte/oxide/semiconductor and to estimate the thickness of the oxide layer. The thicknesses of SiO2 layers calculated from the capacitive impedance were in the range of 25-100Å depending on the experimental conditions. The anodic polarization resistance parallel with the oxide layer capacitance increased continuously to a very large value in ethylene glycol solution. However, it decreased above 4 V in aqueous solutions, where oxygen evolved through the oxidation of water. Interstitially dissolved oxygen molecules in SiO2 layer at above the oxygen evolution potential were expected to facilitate the formation of SiO2 at the interfaces. Thin SiO2 films grew efficiently at a controlled rate during the application of low anodization currents in aqueous solutions.