• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.193-196
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• 2001

Single phase $CuInS_2$ thin film with the highest diffraction peak (112) at diffraction angle $(2\theta)$ of $27.7^{\circ}$ and the second highest diffraction peak (220) at diffraction angle $(2\theta)$ of $46.25^{\circ}$ was well made with chalcopyrite structure at substrate temperature of $70^{\circ}C$, annealing temperature of $250^{\circ}C$, annealing time of 60 min. The $CuInS_2$ thin film had the greatest grain size of $1.2{\mu}m$ and Cu/In composition ratio of 1.03. Lattice constant of a and c of that $CuInS_2$ thin film was 5.60 A and 11.12 A respectively. Single phase $CuInS_2$ thin films were accepted from Cu/In composition ratio of 0.84 to 1.3. P-type $CuInS_2$ thin films were appeared at over Cu/In composition ratio of 0.99. Under Cu/In composition ratio of 0.96, conduction types of $CuInS_2$ thin films were n-type. Also, fundamental absorption wavelength, the absorption coefficient and optical energy band gap of p-type $CuInS_2$ thin film with Cu/In composition ratio of 1.3 was 837 nm, $3.0{\times}104cm^{-1}$ and 1.48 eV respectively. When Cu/In composition ratio was 0.84, fundamental absorption wavelength, the absorption coefficient and optical energy band gap of n-type $CuInS_2$ thin film was 821 nm, $6.0{\times}10^4cm^{-1}$ and 1.51 eV respectively.

• Archives of Pharmacal Research
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• 제27권1호
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• pp.31-34
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• 2004

The electrochemical behavior of doxorubicin hydrochloride was investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV). From CV and SWV studies of doxorubicin hydrochloride in the acetate buffers of various pH values, it was found that protons were involved in the reduction of the antibiotic at the $H^+/e^$- ratio at one ( $\DeltaEp/pH =-53 ∼ -61 mV at 23^{\circ}C$), proposing the electrochemical reduction of the quinone moiety in its anthraquinone aglycone. Its electrochemical behavior was pseudo-reversible in the acetate buffer of pH 3.5 by exhibiting the well-defined single cathodic and anodic waves and the ratio of $lp^a/lp^c$ at approximately one over the scan rates of 10∼100 mV/s. Fast and sensitive SWV showing a single peak of doxorubicin has been applied for its quantitative analysis using an acetate buffer of pH 3.5. A linearity was obtained when the peak currents (lp) were plotted against concentrations of doxorubicin in the range of $5.0\times10^{-7} M∼1.0\times10^{-5}$M with a detection limit of $1.0\times10^{-7}$ M.

• 한국방사선학회논문지
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• 제12권5호
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• pp.557-563
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• 2018

동시 합성 보정 효과는 검출기의 효율이 향상할 때 그리고 선원과 검출기 사이의 거리가 가까울수록 크게 나타나는 것으로 알려져 있다. 점 선원($^{60}Co$)을 사용하여 검출기 중심축 방향 및 방사상 방향에서 거리에 따른 변화를 주어 P/T 비를 구하여 동시합성 보정을 하였다. 따라서 본 연구에서는 중심축 및 방사상 방향에서 동시합성 보정한 값들을 혼합부피선원(450 mL CRM source)에 적용하여 P/T에 따른 전체 피크효율 변화를 Geant4과 비교하였다. 또한 검출기와 시료가 아주 밀착된 상태에서 맵핑법에서 구한 효율을 환경시료 중에서 해양 시료인 미역에 적용하여 P/T 비의 적합성을 평가하고자 한다. 500 keV 이상의 효율의 영향을 받는 에너지 영역에 1,836 keV로 보정한 효율을 적용한 결과 측정값과 보정값의 상대오차는 3.2 % peak 효율이 보정되어 잘 일치하였다. 450 mL CRM source처럼 부피가 커질수록 P/T 비는 ${\pm}5%$까지 감소하였다. 이것은 검출기로부터 선원이 멀어짐에 따라 방출된 감마선의 산란이 많아지기 때문이며, 이처럼 P/T 변화는 동시합성 보정 피크 효율에 영향을 줌을 확인하였다.

• 전자공학회논문지D
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• 제34D권4호
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• pp.27-32
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• 1997

In resonant tunneling diodes with the quantum well structure showing the negative differential resistance (NDR), it is essential to increase both the peak-to-valley current ratio (PVCR) and the peak current desnity ( $J_{p}$) for the accurate digital switching operation and the high output of the device. In this work, a resonant interband tunneling diode (RITD) with single quantum well structure, which is composed of I $n_{0.47}$As/I $n_{0.52}$A $l_{0.48}$As heterojunction on the InP substrate, is fabricated ot improve PVCR and JP, and then the dependence of I-V charcteristics on the width of the quantum well was investigated.d.ted.d.

• JSTS:Journal of Semiconductor Technology and Science
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• 제16권1호
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• pp.143-146
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• 2016

A new area-efficient multi-phase clock frequency multiplier is presented. The proposed fractional-ratio frequency multiplying DLL (FFMDLL) is implemented in a 65 nm CMOS process and occupies an active area of just $0.01mm^2$. The proposed FFMDLL provides 8-phase output clocks and achieves a frequency range of 0.6-1.0 GHz with programmable multiplication ratios of N/M, where N = 4, 5, 8, 10 and M = 1, 2, 3. It achieves an effective peak-to-peak jitter of 5 ps and dissipates 3.4 mW from a 1.0 V supply at 1 GHz.

• 한국식품조리과학회지
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• 제10권1호
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• pp.45-50
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• 1994

본 연구에서는 재래식 된장, Asp. oryzae를 이용한 고지와 소금의 배합을 달리한 개량식 된장 세가지(A; 쌀고지 :콩 :소금:53 : 100 : 33, B: 쌀고지 .콩 :소금=100 : 100 : 40, C: 쌀고지 :콩 :소금=200 : 100 : 40)를 만들어 일반 성분의 변화와 쓴맛 펩타이드의 특성을 살펴보고 쓴맛 펩타이드가 된장의 수응도에 어떠한 영향을 미치는지를 알아보았다. 1. 4가지 된장 모두 총질소는 발효기간 중 약간씩 증가하였으며 아미노산태 질소는 크게 증가하였다. 특히 재래식 된장의 아미노산태 질소는 다른 시료에 비해 큰폭의 증가를 보였다. 환원당은 쌀고지를 첨가한 된장의 경우 함량이 월등힌 많았으며 숙성됨에 따라 모든 된장이 증가 추세를 보였다. pH는 된장이 숙성됨에 따라 점차로 저하하였으며 고지가 첨가된 된장의 경우 더욱 산성을 띠었다. 2. 숙성시킨 된장에서 쓴맛 펩타이드의 특성을 알아보기 위해 소수성 펩타이드를 2 : 1(v/v) Chloroform-me-thanol로 추출하였다. 추출된 추출물을 겔 크로마토그래피를 사용하여 분자량별로 분리하고 다시 TLC로 정제하였다. 정제된 펩타이드는 쓴맛 검사를 하여서 쓴맛을 나타내는 펩타이드를 얻었다. 쓴맛 펩타이드의 아미노산 조성은 다음과 같다. 재래식 된장 peak 1-1. Trp-(Asp, Arg, Thr, Ser, Glu, Pro)-Phe 개량식 된장 B peak 1 Trp-(lie, Pro, Asp, Lys, Val, Glu)-Trp 개량식 된장 B peak 1 Trp-(lie, Pro, Asp, Lys, Val, Glu)-Trp 개량식 된장 C peak 1-2 Trp-(tyr, Thr, Glu, Pro, Gly)-Phe. 3. 관능검사의 결과를 Pearson 상관관계를 알아본 결과 쓴맛과 전체적인 수응도와의 상관관계는 높지 않았다.

• Environmental Engineering Research
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• 제23권3호
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• pp.309-315
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• 2018

Chlortetracycline (CTC) is one of the most important compounds in antibiotic production, and its distribution has been widely investigated due to health and ecological concerns. This study presents systematic approach to optimize the high-performance liquid chromatography-tandem mass spectrometry for analyzing CTC in a multiple reaction monitoring mode ($479{\rightarrow}462m/z$). One-factor-at-a-time (OFAT) test with response surface analysis (RSA) was used as optimization strategy. In OFAT tests, the fragmentor voltage, collision energy, and ratio of acetonitrile in the mobile phase were selected as major factors for RSA. The experimental conditions were determined using a composite in cube design (CCD) to maximize the peak area. As a result, the partial cubic model precisely predicted the peak area response with high statistical significance. In the model, the (solvent composition) and (collision $energy^2$) terms were statistically significant at the 0.1 ${\alpha}$-level, while the two-way interactions of the independent variables were negligible. By analyzing the model equation, the optimum conditions were derived as 114.9 V, 15.7 eV, and 70.9% for the fragmentor voltage, collision energy, and solvent composition, respectively. The RSA, coupled with the CCD, offered a comprehensive understanding of the peak area that responds to changes in experimental conditions.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2003년도 제21회 추계학술대회 논문집
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• pp.6-10
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• 2003

Accurate description of starting transient history allows and justifies the use of small margin of safety for the engine parts, resulting in high motor mass ratio in addition to satisfying the control and guidance requirements of the vehicle. Studies have been carried out for the prediction and reduction of ignition peak and pressure-rise rate during the starting transient of solid rocket motors. Numerical studies have been carried out using a two dimensional Navier-Stokes solver. It has been inferred through the parametric studies that, in the case of solid rocket motors with uniform port, high ignition peak is observed at high spread rate and low pressure-rise rate. In the case of the port with sudden expansion configuration, high ignition peak is observed at relatively high average spread rate and high-pressure rise rate. These studies are expected to aid the designer in reducing the ignition peak by altering the propellant properties or igniter characteristics without sacrificing the motor performance.

• 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 2001년도 추계학술대회 논문집
• /
• pp.193-196
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• 2001

Single phase CuInS$_2$ thin film with the highest diffraction peak (112) at diffraction angle (2$\theta$) of 27.7$^{\circ}$ and the second highest diffraction peak (220) at diffraction angle (2$\theta$) of 46.25$^{\circ}$ was well made with chalcopyrite structure at substrate temperature of 70 $^{\circ}C$, annealing temperature of 25$0^{\circ}C$, annealing time of 60 min. The CuInS$_2$ thin film had the greatest grain size of 1.2 ${\mu}{\textrm}{m}$ and Cu/In composition ratio of 1.03. Lattice constant of a and c of that CuInS$_2$ thin film was 5.60 $\AA$ and 11.12 $\AA$ respectively. Single phase CuInS$_2$ thin films were accepted from Cu/In composition ratio of 0.84 to 1.3. P-type CuInS$_2$ thin films were appeared at over Cu/In composition ratio of 0.99. Under Cu/In composition ratio of 0.96, conduction types of CuInS$_2$ thin films were n-type. Also, fundamental absorption wavelength, the absorption coefficient and optical energy band gap of p-type CuInS$_2$ thin film with Cu/In composition ratio of 1.3 was 837 nm, 3.0x10 $^4$ $cm^{-1}$ / and 1.48 eV respectively. When CuAn composition ratio was 0.84, fundamental absorption wavelength, the absorption coefficient and optical energy band gap of n-type CuInS$_2$ thin film was 821 nm, 6.0x10$^4$ $cm^{-1}$ / and 1.51 eV respectively.