• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1586-1588
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• 1994

Some interesting corona characteristics of a airgap of penpoint-to-plate with a tracing insulator paper has been investigated in a temperature and humidity controlled metal chamber. It is found that the positive and the negative carriers in the plasma region could be understood from the waterdrop traces on the paper, which indicate the bombardment by the one of electron or positive gas particle from the plasma region of near the point. It is also found that a corona discharge could be used as a means of a humidifying, since the discharge makes dispersion of watersprays from the penpoint. And the negative corona was more effective for waterspray dispersion than the positive ones.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.15-19
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• 2012

A new cyclic peptide (six-membered amino acid), gamakamide-E (L-Leu-L-Met (SO)-L-Me-Phe-L-Leu-D-Lys-L-Phe), was isolated as a strongly bitter tasting compound from cultured oysters, Crassostrea gigas. The molecular formula of $C_{43}H_{61}N_7O_8S$ was deduced from high resolution fast atom bombardment mass spectrometry (HR FAB-MS) ($[M+H]^+$ m/z 836.4356 ${\Delta}$= -2.4 mmu). Its unique structure including a hydantoin structure was firstly elucidated by nuclear magnetic resonance (NMR) analysis. Stereochemistries of constituent amino acids were determined by chiral high performanced liquid chromatography analysis of natural and synthesized peptides.

• Archives of Pharmacal Research
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• v.17 no.6
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• pp.424-427
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• 1994

An acinomycin complex isolated from culture broth of a soil microorganism, SNUS 9305-011 has been examined by High performance liquid chromatography (HPLC). From the analysis of the fractions obtained by column chromatography of the ethyl acetate extract, three actinomycin components are confimed . The HPLC analysis is carried out with a CN-bonded nucleosil column. Comparison of the retention times of the components with those of actinomycin D, C complex, $X_{o{\beta}$, and V and suggests that they are different actinomycins. FBA mass spectra fo the coponents also shows different molecular ions from those of standards and other reported actionbmycins. The present work has demonstrated that actinomycin components can be separated by a CN-bonded HPLC column, and that ocmparison of their HPLC chormatograms with authentic smaples and information on their molecular ions can be successfully employed for indentification of actionmycins.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.385-388
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• 2009

We have investigated the effect of the device structure on the performance of polycrystalline ZnO TFT and amorphous AZTO TFT with top gate and bottom gate structure. While the mobility of both TFTs showed relatively similar value in a top and bottom gate structure, bias stability was quite different depending on the device structure. Top gate TFT showed much less Vth shift under positive bias stress compared to that of bottom gate TFT. We attributed this different behavior to the defects formation on the gate insulator induced by energetic bombardment during the active layer deposition in a bottom gate TFT. We suggest the top gate oxide TFT would show more stable behavior under the Vgs bias.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.354-355
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• 2009

In the fabrication of inverted top-emitting organic light emitting diodes (ITOLEDs), the sputtering process is needed for deposition of transparent conducting oxide (TCO) as top anode. Energetic particle bombardment, however, changes the physical properties of underlying layers. In this study, we examined plasma process effects on tungsten oxide ($WO_3$) hole injection layer (HIL). From our results, we suggest the theoretical mechanism to explain the correlation between the physical property changes caused by plasma process on $WO_3$ HIL and degradation of device performances.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.640-643
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• 2007

The effect of plasma damage was investigated on amorphous gallium-indium-zinc oxide (a-GIZO) films and transistors. Ion-bombardment by plasma process affects to turn semiconductor to conductor materials and plasma radiation may degrade to transistor electrical properties. All damages are easily recovered with a $350^{\circ}C$ thermal annealing.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.3
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• pp.23-46
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• 1999

LC/MS는 HPLC의 분리능과 질량분석기의 화합물의 확인 능력을 결합시킨 기기이다. 여기서 사용되는 이온화 방법은 GCJMS에서 사용되어지는 전자이온화법(electron ionization, EI)이나, 화학이온화법(chemical ionization, CI)은 부적당하기 때문에 최근 개발되어진 연성 이온화법의 대표적인 고속원자폭격식(Fast atom bombardment, FAB)이나 전기분무이온화식 (electrospray ionization, ESI) 등이 사용되고 있다. 이중 전기분무이온화법은 고속원자폭격법에서 사용되는 매트릭스를 사용하지 않기 때문에 매트릭스 이온의 부재로 인한 낮은 바탕 신호, 오래 지속되면서 안정된 초기 이온 전류, 샘플링의 용이성, HPLC와의 더 좋은 호환성 등의 장점을 제공한다. 이러한 전기분무이온화 방법은 극성이 매우 크거나 휘발성이 낮은 물질로 보통의 EI나 CI 이온화 방법으로 분석이 어려운 물질들을 분석할 수 있다. 또한 열에 불안정하거나 분자의 분자량이 다른 단백질 등의 분석도 가능하다. 이러한 LC/ESI/MS 방법을 이용하여 열에 불안정하고 극성이면서 분자량이 커서 GC/MS 펄의 분석이 어려운 기능성 화장품 원료로 주목받고 있고 생체에 존재하는 지질 성분으로 알려진 레시틴과 세라마이드의 분석이 가능함을 소개하고 분리와 동시에 그 분자량과 구조에 대한 정보를 빠르게 얻을 수 있음을 소개하였다.

• Journal of Information Display
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• v.6 no.4
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• pp.35-39
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• 2005

In this paper, we investigate the oxide cathodes for the development of reliable electron sources. Poisoning in oxide cathodes is one of the serious problems in achieving reliable electron emission. In particular, early poisoning induces poor life performance as will be demonstrated herein. The survivability of electron emission sources is significantly improved by high doping of high-speed activator. The robust oxide cathodes with 0.17 % Mg operating at about 1,050 K are expected to work for very long times (>100,000 hours). We suggest that this key idea will contribute to solving the basic problems in oxide cathodes such as poisoning or ion bombardment for high power or high frequency applications of electron sources.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.938-941
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• 2000

SrBi$_2$Ta$_2$$O_{9}$(SBT) thin films were etched in Ar/SF$_{6}$ and Ar/CHF$_3$gas plasma using magnetically enhanced inductively coupled plasma(MEICP) system. The etch rates of SBT thin film were 1500$\AA$/min in SF$_{6}$/Ar and 1650 $\AA$/min in Ar/CHF$_3$at a rf power of 600W a dc-bias voltage of -l50V. a chamber pressure of 10 mTorr. In order to examine the chemical reactions on the etched SBT thin film surface , x-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS) were examined. In etching SBT thin film with F-base gas plasma, M(Sr. Bi. Ta)-O bonds are broken by Ar ion bombardment and form SrFand TaF$_2$ by chemical reaction with F. SrF and TaF$_2$are removed more easily by Ar ion bombardmentrdment

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.2
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• pp.62-66
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• 2004

This paper investigated the characteristics of a newly developed high density hollow cathode plasma (HCP) system and its application for the etching of silicon wafers. We used SF$_{6}$ and $O_2$ gases in the HCP dry etch process. Silicon etch rate of $0.5\mu\textrm{m}$/min was achieved with $SF_6$$O_2$plasma conditions having a total gas pressure of 50mTorr, and RF power of 100 W. This paper presents surface etching characteristics on a crystalline silicon wafer and large area cast type multicrystlline silicon wafer. The results of this experiment can be used for various display systems such as thin film growth and etching for TFT-LCDs, emitter tip formations for FEDs, and bright plasma discharge for PDP applications.s.