• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2003년도 춘계학술발표논문집
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• pp.334-336
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• 2003

Polyaniline(PANi) composite panicles were synthesized by chemical oxidation polymerization of aniline in presence of Poly-N-Isopropyl acryl amide(PNIPAM). The PANi panicles are formed in the reaction medium deposited onto non-conducting PNIPAM template to produce PANi-coated composite panicles. The formation of composite was confirmed by FT-IR spectroscopy, and UV-VIS spectroscopy, and their morphological structures were examined by scanning electron microscopy(SEM). From the experimental results, it was determined that PANi was successfully coated onto non-conducting PANIPAM.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.87-88
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• 2011

High absorptance of lightweight aggregate make a hard product, work, quality management ect. for making low absorptance property, lightweight aggregate is coated by an organic matter and that way remarkably showed to decrease the absorptance by pre-study. but first, we would need a check to fit into the concrete which both fresh concrete and hardened concrete. In this study, mechanical property change of coated lightweight aggregate concrete was analysed by compared experiment with coated lightweight aggregate concrete and non-coated aggregate concrete.

• 한국표면공학회지
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• 제41권2호
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• pp.57-62
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• 2008

Electrochemical properties of Ti-30Ta-$(3{\sim}15)$Nb alloys coated by HA/Ti compound layer have been studied by various electrochemical method. Ti-30Ta binary alloys contained 3, 7, 10, and 15 wt% Nb contents were manufactured by the vacuum furnace system. The specimens were homogenized for 24 hrs at $1000^{\circ}C$. The samples were cut and polished for corrosion test and coating. It was coated with HA/Ti compound layer by magnetron sputter. The HA/Ti non-coated and coated morphology of Ti alloy were analyzed by x-ray diffractometer(XRD) and filed emission scanning electron microscope(FE-SEM). The corrosion behaviors were investigated using potentiodynamic method in 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. The homoginazed Ti-30Ta-$(3{\sim}15wt%$)Nb alloys showed the ${\alpha}+{\beta}$ phase, and ${\beta}$ phase peak was predominantly appeared with increasing Nb content. The microstructure of Ti alloy was transformed from needle-like structure to equiaxed structure as Nb content increased. HA/Ti composite surface showed uniform coating layer with 750 nm thickness. The corrosion resistance of HA/Ti composite coated Ti-alloys were higher than those of the non-coated samples in 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. Especially, corrosion resistance of Ti-Ta-Nb system increased as Nb content increased.

• 한국작물학회지
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• 제39권5호
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• pp.473-479
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• 1994

종자가 수분을 흡수할 경우 종자의 내용물이 밖으로 누출되는데 일반적으로 퇴화종자에서 건전종자보다 월등하게 많이 누출되는 특성이 있다. 십자화과 식물의 종자는 형광물질인 sinapine을 함유하고 있어서 수분을 흡수할 경우 퇴화종자에서 다량의 형광물질을 밖으로 배출한다. 이러한 특성을 이용하여 종자를 cellulose로 코팅하여 sinapine을 Cellulose층에 흡착토록 함으로써 퇴화종자를 쉽게 종자 개개의 단위로 선별하는 방법을 개발하였다. 따라서 본 시험에서 국내에 재배되는 십자화과 채소종자에 대해서 이러한 새로운 종자선별법을 이용하여 종자를 선별한 결과 다음과 같은 결과를 얻었다. 1. 십자화과 채소종자의 퇴화종자에서 건전종자 보다 많은 양의 형광물질이 누출되었다. 2. 종자코팅을 통하여 형광종자와 무형광종자를 쉽게 구별할 수 있었다. 3. 형광종자의 비율은 퇴화종자가 많은 품종일수록 높았다. 4. 형광종자를 분리하여 제거하므로써 발아율이 약 5∼35%까지 향상되었다. 5. 무형광종자는 건전한 종자로써 발아율 및 종자세가 무처리종자보다 월등하였고, 형광종자는 대부분 발아하지 않았으며 발아한 묘는 거의가 비정상묘 였다.

• 대한치과보철학회지
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• 제44권2호
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• pp.229-242
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• 2006

Statement of problem: In order to increase preload with reducing the friction coefficient, abutment screws coated with pure gold and Teflon as dry lubricant coatings have been introduced. But the reported data indicate that if screw repeated tightening and loosening cycle, an efficiency of increasing preload was decreased by screw surface wearing off. Purpose: This study was to evaluate the influence of tungsten carbide/carbon coating, which has superior hardness and frictional wear resistance, on the preload of abutment screws and the stability of coating surface after repeated closures. Material and method: The rotational values of abutment screws and the compressive forces between abutment and fixture were measured in implant systems with three different joint connections, one external butt joint and two internal cones. Moreover the stability and the alteration of coating surface were examined by comparison of the compressive force and the removable torque values during 10 consecutive trials, observation with scanning electron microscope and analyzed the elemental composition with energy dispersive x-ray spectroscopy Results and conclusion: 1. Application of coating resulted in significant increase of compressive force in all implant systems(P<.05). The increasing rate of compressive force by coating in external butt joint was gloater than those in internal cones (P<.05). 2. Coated screw showed the significant additional rotation compared to non-coated screw in all implant systems (P<.05). There were no significant differences in the increasing rate of rotation among implant systems (P>.05). 3. Removable torque values were greater with non-coated screw than that with coated screw (P<.05). 4. Coated screw showed insignificant variations in the compressive forces during 10 consecutive trials(P>.05) 5. After repeated trials, the surface layer of coated screw was maintained relatively well. However surface wearing and irregular titanium fragments were found in non-coated screw.

• Corrosion Science and Technology
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• 제10권6호
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• pp.212-217
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• 2011

In this study, corrosion characteristics of TiN and ZrN film on the abutment screw by arc-ion plating were investigated using a potentiodynamic anodic polarization test in deaerated 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. The surface morphologies of the coating layers before and after corrosion test were investigated by a field-emission scanning electron microscope (FE-SEM) and a energy dispersive x-ray spectroscopy (EDS). The surfaces of the TiN and ZrN coated abutment screws showed the smooth surfaces without mechanical defects like scratches which can be formed during the manufacturing process, compared with those of the non-coated abutment screw. The corrosion and passive current densities of TiN and ZrN coated abutment screws were lower than those of the non-coated abutment screw.

• 한국표면공학회지
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• 제55권6호
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• pp.441-447
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• 2022

Silicon-based materials are one of the most promising anode active materials in lithium-ion battery. A carbon layer decorated on the surface of silicon particles efficiently suppresses the large volume expansion of silicon and improves electrical conductivity. Carbon coating through chemical vapor deposition (CVD) is one of the most effective strategies to synthesize carbon- coated silicon materials suitable for mass production. Herein, we synthesized carbon coated SiOx via pilot scale CVD reactor (P-SiO_x@C) and carbon coated SiO_x via industrial scale CVD reactor (I-SiO_x@C) to identify physical characteristic changes according to the CVD capacity. Reduced size silicon domains and local non-uniform carbon coating layer were detected in I-SiO_x@C due to non-uniform temperature distribution in the industrial scale CVD reactor with large capacity, resulting in increased surface area due to severe electrolyte consumption.

• 한국산학기술학회논문지
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• 제4권1호
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• pp.42-46
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• 2003

섬유 코팅제로 널리 쓰이고 있는 액상 PVC는 여러 가지 특성 중 무광택 효과가 뛰어나지만 코팅된 섬유 표면의 유연성이 감소된다. 이런 결함을 대체할 수 코팅 물질로 Elastomer계열의 액상 실리콘 고무를 사용했다. 기존 액상 PVC공정과 동일하게 진행했으며, 로울러의 압축력과 공정상의 예비경화를 이용했다. 실험 결과 액상 PVC로 코팅된 직물의 경도는 70E, 인장강도는 10.3 MPa, 신율은 200%로 측정되었다. 액상 실리콘 고무로 코팅된 직물의 경도는 40도, 인장강도는 5.1 MPa, 신율은 460%,였다. 따라서 액상 실리콘 고무 코팅은 3차 가공 없이 액상 PVC 코팅보다 플라스틱 직물 표면의 무광택성과 유연성을 증가시켰다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.157.2-157.2
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• 2016

Water repellent surfaces may enhance the condensation by efficiently removing the condensed droplets. However, such surfaces may lose their original performance as they are exposed to external mechanical stresses. In this work, we fabricated spray-coated mechanically robust superhydrophobic surfaces using treated titanium dioxide (Type 1) or silica particles (Type 2). Then we compared the mechanical robustness of such surfaces with the silane-coated superhydrophobic surface and PEEK coated surface using a controlled-sand blasting method. The results show that the spray-coated samples can maintain the same level of the contact angle hysteresis than silane-coated superhydorphobic surface after sand blasting at 2 bar. The spray-coating method was applied to the tube type condenser and the condensation behaviors were observed within the environmental chamber with controlled pressure, humidity and non-condensable gas. Previously-reported droplet jumping was observed in the early stage of the condensation event, but soon the droplet jumping stopped and only dropwise condensation was observed since the condensed droplets were pinned on the cracks at spray-coated surfaces. The static contact angle decreases from $158.0^{\circ}$ to $133.2^{\circ}$, and hysteresis increases from $3.0^{\circ}$ to $23.5^{\circ}$ when active condensation occurs on such surfaces. This work suggests the benefits and limitation of spray-coated superhydrophobic condensers and help develop advanced condensers for practical use.

• 미생물학회지
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• 제49권3호
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• pp.275-281
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• 2013

프로바이오틱 박테리아는 면역력 활성 조절, 콜레스테롤 수치 억제, 유당내성 강화, 항종양 활성 등의 다양한 생리활성 기능으로 건강 증진 효과가 있는 것으로 보고되고 있다. 프로바이오틱 박테리아는 일단 섭취하게 되면 위장관을 통과하는 동안 산도가 낮거나 단백질분해 효소가 많은 열악한 환경에서 생존해야 하며 프로바이오틱 효과를 발휘하기 위해 증식해야 한다. 이중 코팅 기술은 펩타이드와 다당류의 이중코팅으로 섭취된 프로바이오틱 박테리아를 열악한 조건으로부터 보호하기 위해 개발되었다. 본 연구에서는 이중코팅 된 4종의 비피도박테리움 혼합물의 생존 안정성을 평가하기 위해 코팅이 되지 않은 비피도박테리움 혼합물과 담즙, 산 저항성 및 열 안정성을 비교 평가하였다. 이중 코팅 된 균주와 코팅이 되지 않은 균주를 산과 담즙 조건 및 $40^{\circ}C$에 노출 시킨 후 한천배지에 배양하여 생존생육 세포수를 측정하였으며, BacLigtht 키트를 이용하여 염색 한 후 유세포 분석기를 이용하여 생균과 사균의 세포수를 평가하였다. 이중코팅 된 균주 혼합물의 경우 코팅이 되지 않은 균주 혼합물 보다 산, 담즙 내성이 더 높았으며, 열 안전성 또한 코팅 되지 않은 균주 혼합물보다 높은 것으로 나타났다. 이 같은 결과들로 이중코팅 기술은 프로바이오틱 박테리아의 안정성 및 섭취 후 위장관 트랙을 통과하는 동안 균주의 생존률을 향상시킬 수 있음을 확인하였다.