• 약학회지
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• 제38권1호
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• pp.38-45
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• 1994

An analytical method using capillary electrophoresis (CE) was developed for quantitation of water soluble vitamin contents in various vitamin products. The method includes the optimization of separation of 11 water soluble vitamins changing the micellar concentration and pH of running buffer, applied voltage and sample preparation. Best resolution was obtained with 25 mM phosphate buffer (pH=8.0) containing 50 mM sodium dodecyl sulphate (SDS) as micellar phase. At optimum condition, water soluble vitamins were determined in orange juice and vitamin products such as vitamin C pulvis, vitamin injection, coated multivitamin tablet. The quantitative analysis of water soluble vitamins with CE was suitable for quality control of pharmaceutical products with sound reproducibility.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.543-544
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• 2008

In the fabrication of inverted top emission organic light emitting diodes (ITOLEDs), the organic layers are damaged by high-energy plasma sputtering process for transparent top anode. In this study, the plasma process induced damages on metal oxide hole injection layers (HILs) including $WO_3$, $MoO_3$, and $V_2O_5$ as buffer layer are examined. With the result of IV characteristic of hole-only devices, we propose that $MoO_3$ and $V_2O_5$ are stable materials against plasma sputtering process.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.966-969
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• 2003

Thin film capacitors with Al-Polymer-Al sandwich structure were fabricated. The bottom and top aluminium (Al) electrodes were deposited by vacuum evaporation and copper phthalocyanine (CuPc), polyaniline-emeraldine base (Pani-EB) and cobalt phthalocyanine/polyaniline - emeraldine base (CoPc /Pani-EB) blend films (which can be used as buffer hole injection layer in OLEDs) were deposited by spin coating technique. X-ray diffractograms indicated amorphous nature of the polymer films whose thicknesses were measured by capacitance and Rutherford Backscattering Spectrometry (RBS) methods. AC conduction studies revealed that the conduction mechanism responsible in these films is variable range hopping of polarons. From D.C conduction studies, it is observed that, the nature of conduction is ohmic in the lower fields and at higher fields the dominating D.C conduction is of Poole-Frenkel type.

• 한국컴퓨터산업교육학회:학술대회논문집
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• 한국컴퓨터산업교육학회 2003년도 제4회 종합학술대회 논문집
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• pp.49-54
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• 2003

In this work, we have seen the effect of hole-transporting layer in organic light-emitting diodes using N,N'-biphenyl-N,N'-bis-(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diamine(TPD) and N,N'-biphenyl-N,N'-bis-(1-naphenyl)-[1,1'-biphenyl]-4,4'-diamine(NPB). NPB is regarded as a better hole trans porting material than TPD, since it has a higher glass transition temperature$(T_g)$. And current -voltage, luminance-voltage and external quantum efficiency of device were measured with the thickness variation of buffer layer using copper phathalocyanine(CuPc) and polytetrafluoroethylene (PTFE) at room temperature. We have obtained an improvement of External quantum efficiency when the CuPc 30[nm] and PTFE 1.0[nm] is used.

• 분석과학
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• 제17권2호
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• pp.192-197
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• 2004

The discrimination of bracken (Korean vs. Chinese) has been attempted using capillary electrophoresis (CE). Bracken (Pteridium aquilinum) was extracted with 30% methanol and separated on a uncoated fused-silica ($50{\mu}m{\times}27cm$) capillary. Conditions for optimal analysis include: temperature, $40^{\circ}C$; voltage, 8 kV; and pressure injection time, 5 sec. The optimal separation buffer was 0.3 M borate buffer (pH 8.5) containing 40 mM CHAPS with 30% ethylene glycol. Under the optimal conditions established for CE, the ratio of specific peak area (peak PA-1) to other peak area (peak PA-2) was effective in discrimination of Korean and Chinese bracken. The mean accuracy for discrimination of Korean and Chinese brackens were 80% and 86%, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.25-28
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• 2000

In this study, Transient Characteristics of the Punch-Through Insulated Gate Bipolar Transistor (PT-IGBT) has been studied. On the contraty to Non-Punch Through Insulated Gate Bipolar Transistor(NPT-IGBT), PT-IGBT has buffer layer It has a simple drive circuit controlled by the gate voltage of the MOSFET and the low on-state resistance of the bipolar junction transistor. In this paper, the transient characteristics with temperature of the PT-IGBT has been analyzed analytically. PT-IGBT is made to reduce switching power loss. Excess Minority carrier distribution inactive base region and base charge, the rate of voltage with time is expressed analytically to include buffer layer.

• Bulletin of the Korean Chemical Society
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• 제15권11호
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• pp.945-949
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• 1994

Mixtures of cyano complexes of palladium(II) and platinum(II) were separated by capillary electrophoresis using a fused silica capillary as a separation column and 30 mM phosphate buffer (pH 7) containing 15 wt. % acetonitrile as a running buffer. By virtue of the high ionic mobilities of the negatively charged cyano complexes of Pd(II) and Pt(II), they were separated using a cathodic injection and anodic detection scheme. The metal complexes eluted through the capillary were detected by direct UV absorption at 214 nm. A linear relationship between peak area and concentration was obtained for both ions and the detection limit was lower than $10^{-14}$ mole. The proposed method was applied to real sample, e.g., anode slime obtained from an electrolytic copper refinary, as a method for the simultaneous determination of palladium and platinum.

• 전자공학회논문지B
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• 제30B권1호
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• pp.38-44
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• 1993

A model for BICMOS buffer switching operation is presented, including the influence of bipolar base transit time and collector-base capacitances. A closed-form solution for the propagation delay-time is obtained assuming low level injection and channel velocity limitation. For the high level injection case, the delay-times are numerically obtained using effective current gain. These results are compared with those by HSPICE simulation, which shows good agreement. It is noted that the collector-base capacitance strongly affects the delay-time. The effects of voltage scaling are also investigated, which shows the model can be applied for the reduced supply voltages.

• Journal of electromagnetic engineering and science
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• 제10권1호
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• pp.35-38
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• 2010

A fully integrated parallel-coupled 6-GHz quadrature voltage-controlled oscillator (QVCO) has been designed. The symmetrical parallel-coupled quadrature VCO is implemented using 0.13-${\mu}m$ CMOS process. The measured phase noise is -101.05 dBc/Hz at an offset frequency of 1 MHz. The tuning range of 710 MHz is achieved with a control voltage ranging from 0.3 to 1.4 V. The average output phase error is about $1.26^{\circ}$ including cables and connectors. The QVCO dissipates 10 mA including buffer from the 1.5 V supply voltage. The output characteristic of the differential injection-locked frequency divider (DILFD), which has similar topology to the QVCO, is presented.

• 한국항행학회논문지
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• 제3권1호
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• pp.1-12
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• 1999

레이다에서 위상측정을 위해서는 송신신호의 위상에 동기된 안정된 신호를 발생하는 코히어런트 발진기(Coherent Oscillator, COHO)가 필요하다. 본 논문에서는 마그네트론에서 발생하는 송신 펄스 신호에 위상동기된 60 MHz의 안정된 신호를 발생하는 COHO Unit를 개발하였다. 송신 펄스의 일부분을 이용하여 ILO(Injection Locking Oscillator)에서 송신펄스에 위상동기된 신호를 발생한다. 게이트 회로, ILO, 완충증폭기, 펄스발생기 등으로 구성된 레이다 COHO를 설계, 제작하여 성능을 검증하였다.