• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.3
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• pp.422-428
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• 2015

A 2.45GHz microwave plasma source with a linear antenna has been developed for low temperature large scale deposition processing. Microwave power is transmitted through WR340 waveguide and a copper rod, linear antenna, is located in a quartz tube. The power matching is effectively achieved by a linear antenna is located at ${\lambda}_g/4$ or $3{\lambda}_g/4$ from the end of WR340 waveguide. The Ar plasma was generated along the surface of quartz tube and a clear standing wave pattern with nearly 10cm wavelength was observed at Ar pressure of 200mTorr and 200W input power. The electron density and electron temperature were investigated by using the electrostatic probe. The electron density and electron temperature were highly measured near the surface of quartz tube. Ar plasma density along the quartz tube is mostly uniform despite standing wave set-up and antenna of long length. A uniform temperature was measured at 10~40cm distance from the end quartz tube and 5cm distance from the surface of quartz tube.

• Electrical & Electronic Materials
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• v.11 no.11
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• pp.17-21
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• 1998

The surface potential distribution on insulating polymers was measured by scanning of the probe of an electrostatic voltmeter. The measurements were done for two measured by scanning of the probe of an electrostatis voltmeter. The measurements were done for two cases. In the first case, it was measured on the free surface of insulating films which had been inserted between plane electodes after the removal of the upper brass disk electrode. In the second case, we measured the charging region between a circular and its opposing concentric ring electrodes after the removal of dc ramp voltage in air and nitrogen gas.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.95.3-95
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• 2002

A multi-channel electrostatic probe is utilized to determine gas flow rate in a cylindrical container. A numerical analysis is conducted to compare experimental measurement with the computed gas velocity in radial and axial directions.

• Journal of Advanced Marine Engineering and Technology
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• v.19 no.4
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• pp.34-41
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• 1995

The structure of premixed tubulent flames in a constant-volume vessel was investigated using a schlieren method and microprobe method. The schlieren method was used to observe the flame structure qualitatively. The microprobe method, which detects a flamelet by detecting its flame potential signal, was used to investigate the deeper flame structure behind the flame front. The flame potential signal having one to six peaks was obtained in the case of turbulent flames, each of them being regarede as a flamelet existing in the flame zone. Based on this consideration, the flame propagation speed, the thickness of the flame zone, the number of flamelets and the separation distance between adjacent flamelets in the flame zone were measured. Moreover, the thickness of flamelet which could not be attempted in the conventional electrostatic probe method was also investigated. The experimental results of this work suggest the existence of "reactant islands" in the reaction zone, and show that the averaged number of flamelets increases with an increase in the turbulence intensity and/or a decrease in the Damkohler number. The mean thickness of flamelet in the case of turbulent flames was found to be about two times compared to laminar values.ar values.

• Archives of Pharmacal Research
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• v.4 no.2
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• pp.99-107
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• 1981

To investigate the protein binding characteristics of ibuprofenlysine, the effects of drub conentration, pH, ionic strength and protein concentration on the binding of drug to protein concentration on the binding of drug to protein were studied by fluorescence probe method. The conformational change of protein was investigated by circular dichroism (CD) measurement. As the concentration of drug increases, the association constant decreases. These may be due to complex formation of the probe and drug, or the interaction of the protein-probe complex and drug. The association constant for ibuprofenlysine increased with increasing protein concentration. These finding suggest a sharing of one ibuprofenlysine molecule by more than one protein molecule in the binding. The binding between ibuprofenlysine and protein was dependent on pH and ionic strength. It seems that both hydrophobic binding and some electrostatic forces are involved in the binding of ibuprofenlysing to protein.

• Macromolecular Research
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• v.14 no.6
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• pp.603-609
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• 2006

Tricyanopyrrolidene chromophores were prepared in order to compare their macroscopic nonlinear optical (NLO) properties with a conjugated structure through the long molecular axis. A thiophene or phenyl ring was tethered to an ethylenic bond; it may act as a lateral moiety to disrupt the planarity of a chromophore and lessen the electrostatic interaction. Thin film composites of these chromophores dissolved in amorphous polycarbonate (APC) were fabricated. Real time pole and probe method was employed to investigate the change of electro-optic (EO) signal during poling. The EO properties and their relaxation behaviors of the guest-host systems containing newly synthesized chromophores were investigated in detail.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.95-97
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• 2004

본 연구에서는 Scanning Capacitance Microscopy (SCM)와 Electrostatic Force Microscopy (EFM)을 이용하여 국소영역에서 실리콘나노 크리스탈의 전기적 특성을 분석하였다. 실리콘 나노 크리스탈은 에어로솔 방식으로 P-type 실리콘웨이퍼 위에 $10{\sim}40\;nm$의 크기와 약 $10^{11}/cm^2$의 밀도를 갖도록 제작하였다. 실리콘 나노 크리스탈에서 전자와 정공의 trapping 현상은 EFM, SCM 이미지를 통하여 관찰하였고 이러한 나노 크리스탈의 국소영역 특성을 MOS 캐패시터 구조의 C-V 특성을 비교 분석하였다. 또한, 나노 크리스탈에 trapping된 전하의 detrapping 과정을 스트레스 조건에 따라 분석하였다.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.42.2-43
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• 2016

Electrostatic fluctuations near upper-hybrid frequency, which are sometimes accompanied by multiple-harmonic electron cyclotron frequency bands above and below the upper-hybrid frequency, are common occurrences in the Earth's radiation belt, as revealed through the twin Van Allen Probe spacecraft. In the literature upper-hybrid emissions are used for estimating the background electron density, which in turn can be used to determine the plasmapause locations, but the role of energetic electrons in generating such fluctuations has not been discussed. The present paper carries out detailed analyses of data from the Waves instrument, which is part of the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) suite onboard the Van Allen Probes. Combined with theoretical calculation, it is demonstrated that the peak intensity associated with the upper-hybrid fluctuations is predominantly determined by tenuous but energetic electrons, and that denser and less energetic background electrons do not contribute much to the peak intensity. This finding shows that upper-hybrid fluctuations detected during quiet time are useful not only for the determination of the electron density, but also they contain information on the ambient energetic electron population as well.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3099-3102
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• 2010

A label-free DNA detection method was developed for a simple electrochemical DNA sensor with a short assay time. Self-assembled monolayers of peptide nucleic acid were used as a probe on gold electrodes. The formation of the self-assembled monolayers on the gold electrodes was successfully checked by means of cyclic voltammetry. The target DNA, hybridized with peptide nucleic acid, can be detected by the anodic peak current of ferrocene dendrimers, which interact electrostatically with the target DNA. This anodic peak current was measured by square wave voltammetry at 0.3 V to decrease the detection limit on the order of the nanomolar concentrations. As a result, the label-free electrochemical DNA sensor can detect the target DNA in concentrations ranging from 1 nM to $1\;{\mu}M$ with a detection limit of 1 nM.

• Journal of the Korean Society of Combustion
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• v.6 no.2
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• pp.36-42
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• 2001

Usually, we use the flame thickness and turbulence scale to classify the flame structure on a phase diagram of turbulent combustion. The flame structure in turbulence is still in debate, and many studies have been done. Since the flame motion is rapid and its reaction zone thickness is very thin, it is difficult to estimate the flame thickness. Here, we propose a new approach to determine the reaction zone thickness based on ion current signals obtained by an electrostatic probe, which has enough time and space resolution to detect flame fluctuation. Since the signal depends on the flow condition and flame curvature, it may be difficult to analyze directly these signals and examine the flame characteristics. However, ion concentration is high only in the region where hydrocarbon-oxygen reactions occur, and we can specify the reaction zone. Based on the reaction zone existing, we estimate the reaction zone thickness. We obtain the thickness of flames both in the cyclone-jet combustor and on a Bunsen burner, compared with theoretically predicted value, the Zeldovich thickness. Results show that the experimentally obtained thickness is almost the same as the Zeldovich thickness. It is concluded that this approach can be used to obtain the local flame structure for modeling turbulent combustion.