• 한국자기학회:학술대회 개요집
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• 한국자기학회 2008년도 Asian Magnetics Conference
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• pp.110.2-110.2
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• 2008

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.57-58
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• 2000

we have grown vertically aligned carbon nanotubes on a large area of Co-Ni codeposited Si substrates by thermal chemical vapor deposition using $C_2H_2$ gas. The carbon nanotubes grown by the thermal chemical vapor deposition are multi-wall structure, and the wall suface of nanotubes is covered with defective carbons or carbonaceous particles. The carbon nanotubes range from 50 to 120 nm in diameter and about 130 ${\mu}m$ in length at $950\;^{\circ}C$. Steric hindrance between nanotubes at an initial stage of the growth forces nanotubes to align vertically. The turn-on voltage was about 0.8 $V/{\mu}m$ with a current density of 0.1 ${\mu}A/cm^2$ and emission current reveals the Fowler-Nordheim mode.

• 한국응용과학기술학회지
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• 제21권4호
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• pp.289-299
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• 2004

Multi-walled carbon nanotubes (CNTs) were prepared by microwave plasma chemical vapor deposition (MPCVD) using various combination of binary catalysts and methane precursor. The maximum yield (10.3 %) of CNTs was obtained using a methane-hydrogen-nitrogen mixture with volume ratio of 1:1:2 at 1000 W of microwave power. As the microwave power increased up to 1000 W, the deposition yield of CNTs raised from 4.1 % to 10. 3 %. However, the prepared CNTs at 800 W showed the more crystalline structure than those prepared at 1000 W. The prepared CNTs over different binary catalysts had various structural conformations such as aligned cylinder, bamboo, and nanofibers. The Id/Ig value of CNTs over$Fe-Fe/Al_2O_3, $Co-Co/Al_2O_3, and $Co-Cu/Al_2O_3 were in the range of 0.89${\sim}$0.93. Among the various binary catalysts used, $Fe-Co./Al_2O_3 showed the highest yield.

• 한국표면공학회지
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• 제47권2호
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• pp.81-85
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• 2014

Ga doped ZnO (GZO)/Al bi-layered films were deposited on the glass substrate by RF and DC magnetron sputtering and then vacuum annealed at different temperatures of 100, 200 and $300^{\circ}C$ for 30 minutes to consider the effects of annealing temperature on the structural, electrical and optical properties of the films. For all depositions, the thicknesses of the GZO and Al films were kept constant at 95 and 5 nm, respectively, by controlling the deposition time. As-deposited GZO/Al bi-layered films showed a relatively low optical transmittance of 62%, while the films annealed at $300^{\circ}C$ showed a higher transmittance of 81%, compared to the other films. In addition, the electrical resistivity of the films was influenced by annealing temperature and the lowest resistivity of $9.8{\times}10^{-4}{\Omega}cm$ was observed in the films annealed at $300^{\circ}C$. Due to the increased carrier mobility, 2.35 $cm^2V^{-1}S^{-1}$ of the films. From the experimental results, it can be concluded that increasing the annealing temperature enhanced the optical and electrical properties of the GZO/Al films.

• 한국항해항만학회지
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• 제37권6호
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• pp.663-671
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• 2013

해운대 해수욕장은 육지로부터 유입되는 모래 공급원의 감소와 고파랑 및 반사파 등의 영향으로 백사장의 폭이 매년 감소하는 것으로 나타났다. 표사이동에 따른 해빈변형 문제를 해결하기 위해서는 해빈류의 특성을 예측할 필요가 있다. 본 연구에서는 해운대 해수욕장에 대한 장기적이고 종합적인 관측자료를 바탕으로, 계절별 대표파랑과 이상파에 대한 해빈류 및 표사이동 수치실험을 실시하였다. 여름에는 평상파 및 S계열 파랑에 의해서 해빈류는 연안을 따라 동쪽으로 흘러 미포측에서 퇴적되는 양상을 보이고, 겨울에는 평상파 및 E 계열의 파랑에 의해 해빈류는 서향하여 동백섬 인근에서 퇴적양상을 보이고 있다. 50년빈도 고파랑 내습시 SSW 파랑은 해운대 중앙에서 이안류가 발생하고, ESE 파랑은 미포측에서 연안을 따라 서측으로 흐름을 발생시키는 것으로 나타났다.

• 한국재료학회지
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• 제18권2호
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• pp.69-72
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• 2008

A sensor element array for combinatorial solution deposition research was fabricated using LTCC (Low-temperature Co-fired Ceramics). The designed LTCC was co-fired at $800^{\circ}C$ for 1 hour after lamination at $70^{\circ}C$ under 3000 psi for 30 minutes. $SnO_2$ sol was prepared by a hydrothermal method at $200^{\circ}C$ for 3 hours. Tin chloride and ammonium carbonate were used as raw materials and the ammonia solution was added to a Teflon jar. 20 droplets of $SnO_2$ sol were deposited onto a LTCC sensor element and this was heat treated at $600^{\circ}C$ for 5 hours. The gas sensitivity ($S\;=\;R_a/R_g$) values of the $SnO_2$ sensor and 0.04 wt% Pd-added $SnO_2$ sensor were measured. The 0.04 wt% Pd-added $SnO_2$ sensor showed higher sensitivity (S = 8.1) compared to the $SnO_2$ sensor (S = 5.95) to 200 ppm $CH_3COCH_3$ at $400^{\circ}C$.

• 한국식품영양학회지
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• 제20권3호
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• pp.245-252
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• 2007

This study investigated the effects of conjugated linoleic acid(CLA) on the fat deposition, triglyceride levels and the expression of stearoyl-CoA desaturase 1(SCD1) in the livers of male ICR mice that were fed with either soybean oil or beef tallow supplemented with CLA. Mice weighing $25{\sim}30$ g were divided into four groups; soybean oil(SBO), and SBO supplemented with 1% CLA(SBOC), beef tallow(BT) and BT supplemented with 1% CLA(BTC). Each group consisted of 10 mice that were fed the experimental diets for 4 weeks. The experimental diets consisted of 64% carbohydrate, 20% protein, and 16% fat in terms of their contributions to total calories. All other nutrients were identical in the diets. Triglyceride measurements were completed using a kit. Fatty acid compositions were analyzed in the liver using gas chromatography. The levels of SCD1 expression were analyzed by RT-PCR in the liver. No significant differences were found for food intake level, body weight and food efficiency among the experimental groups. However, the weights of epididymal fat pads and plasma triglyceride levels were significantly lower in SBOC and BTC(p<0.05) compared to the SBO and BT groups. These effects were similar in the CLA supplemented groups. The expression level of SCD1 gene and ${\Delta}9$ desaturase index were not significantly different, regardless of the fat used for CLA supplementation. Based on these results, addition of CLA showed decreasing effects on the fat depots weight and the concentration of triglyceride regardless of the fat sources. The SCD1 gene expression and ${\Delta}9$ desaturase index were not influenced by the types of fats with respect to the CLA effects.

• 한국초전도ㆍ저온공학회논문지
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• 제10권2호
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• pp.16-19
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• 2008

Angular dependence of critical current density of SmBCO coated conductor fabricated by co-evaporation method was investigated. For comparison, three samples were fabricated by a co-evaporation method and one sample was fabricated by a pulsed laser deposition process. The deposition system, named EDDC (Evaporation using Drum in Dual Chambers), is a batch type co-evaporation system, which is composed of reaction chamber and evaporation chamber. The normalized critical current density ratio ($I_c/I_c$(H//ab-plane)) of EDDC-SmBCO samples was found to be higher than that of PLD-YBCO sample in the whole range of angle. While the EDDC-SmBCO samples evidently had a peak at the angle of H//c-axis in the plot of the angular dependence of critical current, the normalized critical current of PLD-YBCO sample decreased monotonically without any peak as angle increased. The field dependence of critical current under the magnetic field parallel to the normal direction of those samples showed similar aspect in the range of $0\;G{\sim}5000\;G$.

• 반도체디스플레이기술학회지
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• 제23권1호
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• pp.92-96
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• 2024

The application of the technology for forming Al₂O₃ thin films using ALD(atomic layer deposition) method is rapidly increasing in the semiconductor and display fields. In order to increase the efficiency of the ALD process in a mass production line, metallic by-products generated from the ALD process chamber must be effectively collected. By collecting by-products flowing out of the chamber with a cold trap device before they go to the vacuum pump, damage to the vacuum pump can be prevented and the work room can be maintained stably, resulting in increased process flow rate. In this study, a cold trap was installed between the ALD process chamber and the dry pump to measure and analyze by-products generated during the Al₂O₃ thin film deposition process. As a result, it was confirmed that Al and O elements were discharged, and the collection forms were two types: bulk and powder. And the binding energy peaked at 73.7 ~ 74.3 eV, the binding energy of Al 2p, and 530.7 eV, the binding energy of O 1s, indicating that the binding structure was Al-O.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2004년도 제28회 KOSCO SYMPOSIUM 논문집
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• pp.227-234
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• 2004

For gaseous fuel combustion with inherent $CO_2$ capture and low NOx emission, chemical-looping combustion(CLC) may yield great advantages of savings of energy to $CO_2$ separation and suppressing the effect on environment. In chemical-looping combustor, fuel is oxidized by metal oxide medium (oxygen carrier particle) in a reduction reactor. Reduced particles are transported to oxidation reactor and oxidized by air and recycled to reduction reactor. The fuel and the air are never mixed, and the gases from reduction reactor, $CO_2$ and $H_2O$, leave the system as separate stream. The $H_2O$ can be easily separated by condensation and pure $CO_2$ is obtained without any loss of energy for separation. The purpose of this study is to demonstrate inherent $CO_2$ separation and no NOx emission and to confirm high $CO_2$ selectivity, no side reaction (i.e., carbon deposition, hydrogen generation) by continuous reduction and oxidation experiment in a 50kWtb chemical-looping combustor. NiO/bentonite particle was used as a bed material and $CH_4$ and air were used as reacting gases for reduction and oxidation respectively.