• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 추계 수산관련학회 공동학술대회발표요지집
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• pp.149-150
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• 2001

A fish feed being used most widely in aquacultural farm is a moist pellet (MP) feed which has been being prepared by mixing of commercial dry feed and nutritional oil to raw fish ky. The two major problems in the use of MP feed is to be readily dispersed in water of an aquacultural farm, and to cause lipid oxidation and bacteria infection during storage. The former induce an environmental pollution of the farm and the latter lower nutritional values and develop fish diseasees. (omitted)

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권7호
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• pp.359-363
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• 2006

Single-walled carbon nanotubes (SWCNTs) with few defects and very small amount of amorphous carbon coating have been synthesized by catalytic decomposition of methane in $H_2$ over well-dispersed metal particles supported on MgO. The yield of SWCNTs was estimated to be 88.5% and the purities of SWCNTs thus obtained were more than 90%. Peak of the radial breathing mode in the Raman spectrum demonstrated that the diameters of synthesized CNTs are in the range 0.4-2.0 nm. Our results also indicated that MgO support materials are useful to a large-scale synthesis of high-quality SWCNTs. Increasing temperature could remarkably increase the yield and also improve the quality of SWCNTs from catalytic decomposition of methane. The morphologies and microstructures of the synthesized carbon materials were characterized by scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), Raman spectroscopy, and X-ray diffraction (XRD).

• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.231-236
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• 2013

Some cytotoxicity studies for the interpretation of the interaction between nanoparticles and cells are non-mechanistic and time-consuming. Therefore, non-biological screening methods, which are faster and simpler than in-vivo and in-vitro methods, are required as alternatives to current cytotoxicity tests. Here, we proposed a simple screening method for the analysis of the interaction between several AgNPs (bare-, citrate-, and polyvinylpyrrolidone-coating) and dye-containing vesicles acting as a biomimetic cell-membrane. The interaction between AgNPs and vesicles could be evaluated readily by UV-vis spectra. Absorbance deviation in UV-vis spectra revealed a large attraction between neighboring particles and vesicles. This was confirmed by (Derjagin, Landau, Verwey, and Overbeek) theory and DMF (dark-field microscopy) analysis. This proposed method might be useful for analyzing the cytotoxicity of nanoparticles with cell-membranes instead of in vitro or in vivo cytotoxicity tests.

• 한국산학기술학회논문지
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• 제8권6호
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• pp.1579-1582
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• 2007

본 연구는 광촉매를 이용, 수용액내 유기오염물질 분해 성능을 비교하여 난분해성 오염물질을 분해하는 최적의 조건을 찾는 것으로 반응기 내부의 광원의 파장에 따른 세기와 광촉매 물질의 상태에 따라 고찰하였다. 그 결과, $500^{\circ}C$에서 30동안 소성한 실리카 비드가 가장 뛰어난 반응성을 나타냄을 알 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1378-1379
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• 2006

Carbon nanotubes (CNTs) with few defects and very small amount of amorphous carbon coating have been synthesized by catalytic decomposition of acetylene in $H_2$ over well-dispersed metal particles supported on MgO. The yield, quality and diameters of CNTs were obtained by control of catalyst metal compositions to be used. The optimization condition of carbon nanotubes with high yield is when Co and Mo are in a 1:1 ratio and Fe metal contents to Co is increased on magnesium oxide support. It is also found that the diameter of the as-prepared CNTs can be controlled mainly by adjusting the molar ratio of Fe-Mo, Co-Fe, and Co-Mo versus the MgO support. Our results indicated that desired diameter distribution of CNTs is obtained by choosing or combining the catalyst to be employed.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2015년도 춘계학술대회 논문집
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• pp.108-108
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• 2015

In order to investigate on hydroxyapatite precipitation phenomena on nanotubular Ti-29Nb-xHf ternary alloys, Ti-29Nb-xHf alloys contained (0% to 15%) Hf were manufactured using arc melting furnace. Formation of nanotubular structure was achieved by an electrochemical method in 1M $H_3PO_4$ electrolytes containing 0.8%wt. % NaF. Electrochemical deposition was carried out using cyclic and voltammetry(CV) method at $85^{\circ}C$ in $5mM\;Ca(NO_3)_2+3mM\;NH_4H_2PO_4$. HA coating on nanotube formed Ti-29Nb-xHf ternary alloys showed a good wettability.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2004년도 춘계학술대회
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• pp.291-293
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• 2004

본 연구에서는 대전방지 효과를 나타낼 수 있는 열경화형 반응성 대전방지제를 합성하여 그 응용성을 고찰하였다. 열경화성 대전방지제는 수용성 수지에 무게비로 $5\~20wt\%$범위로 첨가하여 사용하였으며 코팅 도막 형성을 위하여 PVC인테리어필름에 코팅 후, $80\~150^{\circ}C$에서 2$\~$20분 경화시켰다. 코팅된 PVC 인테리어필름의 대전방지성을 고찰한 결과, 부착력, 대전방지성, 내오염성 둥이 우수하였으며 코팅막의 두께와 첨가량에 따라 대전성과 부착력에 차이가 있음을 알 수 있었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.321-321
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• 2010

The PEDOT:PSS layer is usually used as hole transporting layer for the polymer bulk heterojunction solar cells. However, the interface between ITO and PEDOT:PSS is not stable and the chemical reaction between ITO and PEDOT can result in degraded device performance. We used the tungsten oxides as a hole transport layer by spin-coating. The $WO_3$ nanoparticles were well dispersed in ammonium hydroxide and deionized water and formed thin layer on the ITO anode. We found that $WO_3$ surface is more hydrophobic than the bare ITO or PEDOT:PSS-coated surfaces. The hydrophobic surfaces promote an ordered growth of P3HT films. A higher degree of P3HT ordering is expected to improve the hole mobility and the lifetime of the device using the tungsten oxide showed better stability compared to the device using the PEDOT:PSS.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.427-431
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• 2005

In this study, 6' GaAs wafer bonding system is designed and optimized to bond 6 inches device wafer and material wafer. Bonding process is performed in vacuum environment and resin is used to bond two wafers. Vacuum module and double heating mechanisms are adopted to minimize wafer warpage and void. Structure and heat transfer analysis, et al of the core modules review the designed mechanisms are very effective in performance improvement. As a result, high productivity (tack time cut-down) and stabilized process can be obtained by reducing breakage failure of wafer.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제16권3호
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• pp.193-204
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• 2012

This paper is comparing numerical schemes for a differential equation with convection and fourth-order diffusion. Our model equation is $h_t+(h^2-h^3)_x=-(h^3h_{xxx})_x$, which arises in the context of thin film flow driven the competing effects of an induced surface tension gradient and gravity. These films arise in thin coating flows and are of great technical and scientific interest. Here we focus on the several numerical methods to apply the model equation and the comparison and analysis of the numerical results. The convection terms are treated with well known WENO methods and the diffusion term is treated implicitly. The diffusion and convection schemes are combined using a fractional step-splitting method.