• YAKHAK HOEJI
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• v.11 no.3_4
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• pp.33-35
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• 1967

The internal structures of "Chunho", "Kangwhal" and "Dangui" and their original plants had been compared with each other in the prior report. Coumarin derivatives, khellactone from the roots of Angelica purpuraefolia $C_{HUNG}$ and decursin and decursinol from A. gigas $N_{AKAI}$ were also isolated. In this report, we made a simple and convenient identification method for the powdered drugs of several Angelica genus by using a thin layer chromatogrophic technique. The ehter extract of the powdered drugs were applied to a silica gel plate, and was developed with n-hexane and ethyl acetate (1:1) mixture. The characteristic U.V. absorption patterns of each drug were shown.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.2
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• pp.112-115
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• 2011

To stabilize the electric characteristic of Silicon Thin Film Transistor, reducing the current leakage is most important issue. To reduce the current leakage, many ideas were suggested. But the increase of mask layer also increased the cost. On this research Bird's Beak process was use to present element. Using Silvaco simulator, it was proven that it was able to reduce current leakage without mask layer. As a result, it was possible to suggest the structure that can reduce the current leakage to 1.39nA without having mask layer increase. Also, I was able to lead the result that electric characteristic (on/off current ratio) was improved compare from conventional structure.

• Journal of the Korean Applied Science and Technology
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• v.16 no.1
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• pp.41-44
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• 1999

Recently, high luminance and efficiency were realize in organic thin film electroluminescence (EL) cells with multilayer structures including an emitting layer (EML), hole transporting layer (HTL), and an electron transporting layer (ETL). In this study, Bis(10-hydroxybenzo[h]quinolinato)beryllium (Bebq2) was synthesized. PL and EL characteristics of their thin film were investigated by fabricating the devices having a structure of ITO/PVK/Bebq2/Al, ITO/PVK dispersed with TPD/Bebq2/Al. The EL color of these device was greenish and the wavelength of their EL peaks was located, respectly, at 495nm, and 492.5nm.

• International Journal of Advanced Culture Technology
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• v.3 no.2
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• pp.138-143
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• 2015

This paper was aimed to study the drying kinetics of coffee and to investigate the thin-layer drying kinetics of coffee by using a convective air dryer. The coffee was dried for the temperatures of 40, 50 and $60^{\circ}C$ with relative humidity in the range of 14-25% the airflow rate fixed at 1 m/s. According to the experiment result, the drying rate curve showed that drying process took place only in the falling rate period. Seven thin layer drying models (Newton, Page, Henderson and Pabis, Logarithmic, Wang and Singh, Two terms, Modified Henderson and Pabis) were fitted to the experimental moisture content data. The Two-trem model was found to be a better model for describing the characteristics of coffee for the temperatures of 40, 50 and $60^{\circ}C$. The effective moisture diffusivity of coffee increased when the drying temperature increased. The value was in the range of $4.5028{\times}10^{-11}$ to $6.4803{\times}10^{-11}m^2/s$.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.849-852
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• 2007

We studied ZnO thin films deposited with DC magnetron sputtering for channel layer of TFTs. After analyzing of the basic physical and chemical properties of ZnO thin films, we fabricated a TFTunit test cell. The field effect mobility of $1.8\;cm^2/Vs$ and threshold voltage of -0.7 V were obtained.

• Journal of Environmental Health Sciences
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• v.6 no.1
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• pp.23-26
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• 1979

한국에서 사용하고 있는 carbamate계 살충제의 사용율(%)은 1968년경에는 2.1%인데 비해서 현재는 급증되고 있는 실정에 있다. 따라서 이로 인한 자타살 사건, 환경오염, 살포시 급만성 중독 등의 사고가 빈번히 발생하고 있는 동시에 법화학적 분석에도 많은 문제점이 되두되고 있으므로 1차적으로 시판되고 있는 carbamate계 살충제를 thin layer chromatography에 의해서 성분의 분리 확인 시험을 실시한 결과 1) Silica Gel G-60 및 Silica Gel F-254에서 적합하였고 2) 전개용매는 chloroform: benzeneP: carbontetra chloride (60:30:25), cyclohexane: acetone (80:20), cyclohexane:acetone(70:30), ether:hexane(80:20)에서 9종의 살충제가 잘 분리되었으며 3) UV light (2537 ${\AA}$) 및 2.6-dibromoquinone-4-chlorimide는 전개는 Rf치를 육안으로 구분하는데 가장 양호하였고 4) Carbamate계 살충제 중 Bux-2와 Sevin은 Silica Gel G-60에서 UV light (2537 ${\AA}$)에서 특이한 청보라 및 청색형광을 관찰할 수 있었다. 5) 이상의 결과를 보아 법화학적 시료중에 함유된 카바메이트계 농약의 분석은 가능할 것이며 또한 이 방법의 적용이 현재의 실정으로서는 적합한 것으로 사료되는 바이다.

• Journal of the Korean Ceramic Society
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• v.54 no.3
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• pp.249-256
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• 2017

We design Ge-Al multilayer assemblies as anode materials for Li-ion batteries, in which Ge and Al thin films are alternately deposited by a radio sputtering method. By sandwiching Ge layers between Al layer, the cyclability, rate capability, and capacity of Ge are improved significantly. The success of the Ge-Al multilayer is attributed to the Al films. To maintain the integrity of electrical contact, Al acts as an elastic layer, which can expand or shrink with the Ge film upon lithiation or delithiation. In addition, the presence of the Al film on the surface can prevent direct contact of Ge and electrolyte, thereby reducing the growth of a SEI layer. Importantly, with high electrical and ionic conductivities, the Al film provides efficient electrical and ionic routes for electrons and Li-ions to access the Ge film, promoting a high specific capacity and high rate capability for Ge.

• Journal of the Korean Wood Science and Technology
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• v.21 no.2
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• pp.67-72
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• 1993

Hot water extractives of sawdust/particle from domestic and foreign wood species, which were composed of pitch pine, Korean pine, larch, Italy poplar, acacia and oak as Korean wood species, Malaysian oil palm and German spruce were quantitatively analyzed with thin layer chromatography. Sugar components of saccharose, galactose, glucose, fructose and arabinose were contained in these wood species. It was assumed that arabinose and glucose are major inhibitory components against cement hardening in larch and oil palm, respectively, since both species contain a large amount of each sugar. In contrast, fructose might not influence so badly on a cement hardening, when considering that fructose was contained much in Italy poplar with a good cement hardening character. Galactose was a minor component.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.04a
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• pp.128-129
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• 2007

$ZnS/Na_3AlF_6$ multi-layer thin film were produced by evaporation system. ZnS were selected as a high refractive index material and $Na_3AlF_6$ were selected as low refractive index material. Optical properties including color effect were systematically studied in terms of different optical thickness by spectrophotometer. In oder to compare with experimental data, the Essential Macleod Program(EMP) was adopted that simulation program. The thin film consisting of $ZnS/Na_3AlF_6$ multi-layer show the wave length of $530{\sim}600nm$, typically color range between purple, blue, green. It was confirmed that this experimental result was well matched with simulation data.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.5
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• pp.340-346
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• 2021

The initial electrochemical performance of ceramic fuel cell with thin-film electrolyte fabricated by plasma-enhanced atomic layer deposition method was evaluated in terms of peak power density ratio, open circuit voltage ratio, and activation/ohmic resistance ratios at 500℃. Hydrogen and air were used as anode fuel and cathode fuel, respectively. The peak power density ratio reduced as ~52% for 30 min, which continually decreased as time increased but degradation rate gradually decreased. The open circuit voltage ratio decreased with respect time; however, its behavior was evidently different from the reduction behavior of the peak power density. The activation resistance ratio increased as ~127% for 30 min, which was almost similar with the reduction behavior of the peak power density ratio.