• 제목/요약/키워드: Nano solution

검색결과 1,211건 처리시간 0.037초

미세 hydorxyapatite 분말을 이용한 개선된 치아표면의 미세구조 (Microstructure of Improved Tooth Surface Using Fine Hydroxyapatite Powder)

  • 류수착;임병기;김홍성;박영민
    • 한국재료학회지
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    • 제17권10호
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    • pp.544-547
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    • 2007
  • Human teeth were scratched by the abrasive paper, dropping in hydroxyapatite solution during 1, 2, 3, 4 months. We studied teeth surface change with SEM each months. After 1 months treatment the surface appeared the change. Because of the hydroxyapatite ion exchange mechanism. The scratched surface was recovered by the hydroxyapatite. The results of EDS showed that $Ca^{2+}$ ion and $PO_4^{3-}$ ion were removed from hydroxyapatite solution to scratched teeth surface.

Anodic oxidation behavior of AZ31 Mg alloy in aqueous solution containing various NaF concentrations

  • Moon, Sungmo;Kwon, Duyoung
    • 한국표면공학회지
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    • 제55권4호
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    • pp.196-201
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    • 2022
  • This paper deals with anodic oxidation behavior of AZ31 Mg alloy in aqueous solutions containing various NaF concentrations from 0.01 M to 1 M. Three different voltage-time curves and anodic oxide formation behaviors appeared with concentration of NaF in deionized water. When NaF concentration is lower than 0.02 M, the voltage of AZ31 Mg alloy increased linearly and then reached a steady-state value more than 200 V, and large size pits and thin oxide layer were formed. When NaF concentration is between 0.05 M and 0.1 M, the voltage of AZ31 Mg alloy showed large periodic fluctuations of about 30 ~ 50 V around more than 200 V and large number of small particles were observed. If NaF concentration is higher than 0.2 M, PEO films can be formed without visible arcs under solution pH 6.5 ~ 7.5 by F- ions without help of OH- ions.

Indium-tin oxide (ITO) 나노 입자 용액을 이용한 직접 ITO 나노 패턴 제작 기술 (Direct indium-tin oxide (ITO) nano-patterning using ITO nano particle solution)

  • 양기연;윤경민;이헌
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2009년도 추계학술대회 초록집
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    • pp.247-247
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    • 2009
  • 본 연구에서는 indium-tin oxide (ITO) 나노 입자 용액을 이용하여 간단한 공정을 통해 ITO 나노 패턴을 직접적으로 제작하는 기술에 대한 연구를 진행하였다. 이를 이용하여 300nm급 ITO 나노 dot 패턴을 제작하는데 성공하였으며 이를 glass 표면에 구현하는데 성공하였다.

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초음파분무 연소법에 의한 나노결정 ZnO 초미분체 제조 (Preparation of Nanocrystalline ZnO Ultrafine Powder Using Ultrasonic Spraying Combustion Method)

  • 김광수;황두선;구숙경;이강;전치중;이은구;김선재
    • 한국재료학회지
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    • 제12권10호
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    • pp.784-790
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    • 2002
  • For mass product of nanocrystalline ZnO ultrafine powders, self-sustaining combustion process(SCP) and ultrasonic spray combustion method(USCM) were applied at the same time. Ultrasonic spray gun was attached on top of the vertical type furnace. The droplet was sprayed into reaction zone of the furnace to form SCP which produces spherical shape with soft agglomerate crystalline ZnO particles. To characterize formed particles, fuel and oxidizing agent for SCP were used glycine and zinc nitrate or zinc hydroxide. Respectively, with changing combustion temperature and mixture ratio of oxidizing agent and fuel, the best ultrasonic spray conditions were obtained. To observe ultrasonic spray effect, two types of powder synthesis processes were compared. One was directly sprayed into furnace from the precursor solution (Type A), the other directly was heated on the hot plate without using spray gun (Type B). Powder obtained by type A was porous sponge shape with heavy agglomeration, but powder obtained using type B was finer primary particle size, spherical shape with weak agglomeration and bigger value of specific surface area. 9/ This can be due to much lower reaction temperature of type B at ignition time than type A. Synthesized nanocrystalline ZnO powders at the best ultrasonic spray conditions have primary particle size in range 20~30nm and specific surface area is about 20m$^2$/g.