• Title/Summary/Keyword: 금속 입자

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이달의 과학자 - 한양대 공학대 금속재료공학과 '이재성 교수'

  • Korean Federation of Science and Technology Societies
    • The Science & Technology
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    • v.32 no.6 s.361
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    • pp.22-23
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    • 1999
  • 21세기 첨단기술로 다기능성 금속과 세라믹 나노입자 재료기술이 부상하고 있다. 한양대 금속재료공학과 이재성교수는 활발한 국제적 협력을 바탕으로 나누구조재료에 관한 연구를 계속하고 있다. 현재 국제 나노구조재료학회 국제상임위원으로 한국을 대표하고 있는 이교수는 '나노입자분말 합성기술 및 치밀화 기술개발과 다기능성 나노벌크재료기술을 핵심기술로 발전시켜 나갈 계획"이라고 강조했다.

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Study on the Thermal Behavior and Adhesion Properties of Polyurethane Hot Melt Adhesive via Induction Heating (유도가열에 의한 폴리우레탄 핫멜트 접착제의 열적 거동 및 접착특성 연구)

  • Jeon, Ho Kyyon;Park, Hyun Ju;Lee, Ji Eun;Lee, Jonh Hwan;Oh, Sang Taek
    • Journal of Adhesion and Interface
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    • v.19 no.4
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    • pp.167-172
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    • 2018
  • In this study, a polyurethane hot melt adhesive was synthesized and metal particles sensitive to induction heating were added to produce an induction heating melt adhesive. The thermal behavior and adhesion characteristics of metal particles were investigated according to the kind, size and induction heating conditions. Among the various metal particles, induction heating efficiency was the best when nickel and iron were applied. Induction heating efficiency increased with decreasing metal particle size. In addition, the strength of the induction heating power of the adhesive was high and the adhesive strength was improved as the adhesive thickness was thinner.

Manufacturing and Characterization of SiC/AI Metal Matrix Composite by Modified Gas Metal Arc Welding Process ; Manufacturing and Microstructure (개조된 GMA용접공정을 이용한 SiC/AI 복합재료의 제조 및 특성)

  • Kim, Gwang-Su
    • Korean Journal of Materials Research
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    • v.6 no.11
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    • pp.1090-1098
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    • 1996
  • 개조한 가스 금속 아아크 용접공정을 이용하여 SiC/AI 금속기 복합재료를 제조하고 그 특성을 조사하였다. AI 모재위에 강화입자의 크기와 부피분율을 변화하여 다양한 SiC/AI 복합재료층을 제조하였고, 만들어진 복합재료층의 특성은 미세조직관찰과 미소경도시험을 통하여 이루어졌다. 복합재료층의 두께는 약 7-8mm로 측정되었고 균일한 강화입자의 분포도를 얻을 수 있었다. 분산입자의 부피분률은 Ar가스의 유량에 의하여 조절하였고 분산입자의 부피분률이 증가하고 크기가 작아짐에 따라 기지의 수지상 응고조직은 더욱 미세화되었다. 복합재료의 부피경도는 분산입자의 부피분률이 감소함에 따라 낮아졌으나 입자 크기에는 크게 변화가 없는 것으로 나타났다.

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Mass Production of Carbon Nanotubes Using Magnetic Fluids (자성유체를 이용한 탄소나노튜브의 대량 합성)

  • 조유석;최규석;김도진
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2003.10a
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    • pp.37-41
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    • 2003
  • 열화학 기상합성법을 이용한 탄소나노튜브의 성장에서 촉매 금속 층의 형성 공정은 탄소나노튜브의 직경 및 길이를 제어해주는 가장 중요한 요소이다. 탄소나노튜브의 대량합성을 위해 자성유체를 이용한 촉매 금속 층의 손쉬운 형성공정을 개발하였다. 수용성 폴리비닐알코올과 마그네타이트 나노 입자들이 혼합된 자성유체를 다양한 기판에 스핀 코팅하여 촉매 금속 층을 간편하게 형성할 수 있었다. 자성유체 제조 시 혼합된 수용성 폴리비닐알코올은 자성유체용액의 점성을 증가 시켜 주었으며, 이러한 점성의 증가는 스핀 코팅 시 용액과 기판간의 접착력을 증대시켜 주었다. 또한 건조 과정 이후에도 잔류되어 탄소나노튜브 합성 공정 중에 촉매금속이 응집되는 현상을 방지 차여 균일한 입자 크기를 유지하도록 하였다. 이는 고밀도의 수직 배열된 탄소나노튜브의 성장의 직접적인 원인으로 생각된다. 또한 탄소나노 튜브의 대량 합성을 위해서 Si 기판 치에 알루미나와 금속 기판에서도 탄소나노튜브의 성장을 시도하였다.

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Ag-functionalized SnO2 Nanowires Based Sensor for NO2 Detection at Low Operating Temperature (NO2 감응을 위한 Ag 금속입자가 기능화된 SnO2 나노선 기반 저온동작 센서)

  • Choi, Myung Sik;Kim, Min Young;Ahn, Jihye;Choi, Seung Joon;Lee, Kyu Hyoung
    • Journal of the Microelectronics and Packaging Society
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    • v.27 no.2
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    • pp.11-17
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    • 2020
  • In this study, Ag-functionalized SnO2 nanowires are presented for NO2 gas sensitive sensors at low temperatures (50℃). SnO2 nanowires were synthesized using vapor-liquid-solid method, and Ag metal particles were functionalized on the surface of SnO2 nanowires using flame chemical vapor deposition method. As a result of the sensing test about Ag-functionalized SnO2 nanowires based sensor, the response (Rg/Ra) to 10 ppm NO2 was 1.252 at 50℃. We believe that metal-functionalizing is a one of good way to increase the feasibility about semiconductor gas sensor.

금속나노물질의 합성과 유연전기소자 응용

  • Go, Seung-Hwan
    • Journal of the KSME
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    • v.55 no.12
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    • pp.45-48
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    • 2015
  • 이 글에서는 금속나노물질(나노와이어, 나노입자)의 액상합성법(wet chemistry)과 합성된 금속나노물질을 이용한 유연전기소자 개발의 응용에 대해 소개하고자 한다.

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Preparation and Characterization of Microfiltration Membrane by Metal Particles (금속입자를 이용한 정밀여과막 제조와 특성평가)

  • Kim, In-Chul;Lee, Kew-Ho;Park, Joo-Young;Jeong, Bo-Reum;Kwon, Ja-Young
    • Membrane Journal
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    • v.17 no.4
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    • pp.381-386
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    • 2007
  • Hollow fibers were made using the nickel slurry containing nickel particles and polymers by phase inversion method. And then, metallic filters were fabricated by sintering method at $1,150^{\circ}C$ under reduction condition. Metallic microfiltration membranes were prepared by coating nickel particles on the metallic filter. The properties of the metallic hollow fiber filters and microfiltration membranes such as pore size and strength were investigated. The metallic membrane showed good resistance against acid, base and chlorine. It was observed that the membrane exhibited good recovery rate by back washing.

Synthesis, Characterizations, and Applications of Metal-Ions Incorporated High Quality MCM-41 Catalysts (고품질 금속 이온 첨가 MCM-41 분자체 촉매의 제법, 특성화 및 응용 반응)

  • Lim, Steven S.;Haller, Gary L.
    • Korean Chemical Engineering Research
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    • v.51 no.4
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    • pp.443-454
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    • 2013
  • Various metal ions (transition and base metals) incorporated MCM-41 catalysts can be synthesized using colloidal and soluble silica with non-sodium involved process. Transition metal ion-typically $V^{5+}$, $Co^{2+}$, and $Ni^{2+}$-incorporated MCM-41 catalysts were synthesized by isomorphous substitution of Si ions in the framework. Each incorporated metal ion created a single species in the silica framework, single-site solid catalyst, showing a substantial stability in reduction and catalytic activity. Radius of pore curvature effect was investigated with Co-MCM-41 by temperature programmed reduction (TPR). The size of metallic Co clusters, sub-nanometer, could be controlled by a proper reduction treatment of Co-MCM-41 having different pore size and the initial pH adjustment of the Co-MCM-41 synthesis solution. These small metallic clusters showed a high stability under a harsh reaction condition without serious migration, resulting from a direct anchoring of small metallic clusters to the partially or unreduced metal ions on the surface. After a complete reduction, partial occlusion of the metallic cluster surface by amorphous silica stabilized the particles against aggregations. As a probe reaction of particle size sensitivity, carbon single wall nanotubes (SWNT) were synthesized using Co-MCM-41. A metallic cluster stability test was performed by CO methanation using Co- and Ni-MCM-41. Methanol and methane partial oxidations were carried out with V-MCM-41, and the radius of pore curvature effect on the catalytic activity was investigated.

Dust Removal Efficiency and Operation Characteristics of Metal Filters for Coal Gasification Fines and Standard Dust Sample (금속필터를 사용한 석탄가스화 분진 및 표준 분진의 집진 효율과 운전특성)

  • Yun, Yongseung;Chung, Seok Woo;Lee, Seung Jong
    • Korean Chemical Engineering Research
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    • v.57 no.4
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    • pp.461-468
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    • 2019
  • Demand for improving dust removal efficiency in coal power plants and the dust removal requirement to the level of capturing fine particulate matter and ultrafine particles have been increasing. While bag filter and electrostatic precipitator (ESP) are typically used for dust removal in the processes operating at atmospheric pressure, metal filters or ceramic filters are employed for dust which is produced at high temperature/pressure system as in coal gasification. For dust removal at the high temperature/pressure conditions, two metal filters of five compressed/sintered layers were manufactured and applied to analyze the dust removal characteristics. Manufactured metal filters exhibited more than 99% dust removal efficiency on coal gasification fine particulates in mass basis. To evaluate the fine particulate removal efficiency of less than $2.5{\mu}m$, JIS standard fine sample was used and confirmed the removal efficiencies of 97% and 70~82% on the fine particulates of $1{\sim}2.5{\mu}m$ size range. For the size range of less than $1{\mu}m$, dust removal efficiency of manufactured metal filters significantly degraded with smaller particle size. Improving methods are proposed to overcome the limitations in applying to fine dust of less than $1{\mu}m$.