• 제목/요약/키워드: hybrid materials

검색결과 1,841건 처리시간 0.036초

알루미늄-복합재료 혼성 사각관 보의 굽힘 성능평가 (Bending Performance Evaluation of Aluminum-Composite Hybrid Square Tube Beams)

  • 이성혁;최낙삼
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2005년도 춘계학술발표대회 논문집
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    • pp.76-79
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    • 2005
  • Bending deformation and energy absorption characteristics of aluminum-composite hybrid tube beams have been analyzed for improvement in the bending performance of aluminum space frame by using experimental tests combined with theoretical and finite element analyses. Hybrid tube beams composed of glass fabric/epoxy layer wrapped around on aluminum tube were made in autoclave with the recommended curing cycle. Basic properties of aluminum material used for initial input data of the finite element simulation and theoretical analysis were obtained from the true stress-true strain curve of specimen which had bean extracted from the Al tube beam. A modified theoretical model was developed to predict the resistance to the collapse of hybrid tube beams subjected to a bending load. Theoretical moment-rotation angle curves of hybrid tube beams were in good agreement with experimental ones, which was comparable to the results obtained from finite element simulation. Hybrid tube beams strengthened by composite layer on the whole web and flange showed an excellent bending strength and energy absorption capability.

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Fabrication of Organic-Inorganic Hybrid Thin Film by Molecular Layer Deposition

  • 한규석;김수환;한기복;성명모
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
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    • pp.251-251
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    • 2010
  • Organic-inorganic hybrid materials have attracted because of its combined properties, such as flexibility and high electrical performance. In addition, the hybrid materials are expected to have synergic effect which are not shown in just one component. Here, we fabricated organic-inorganic hybrid thin film. Organic-inorganic hybrid thin film have been deposited from diethyl zinc and 1, 2, 4-trihydroxybenzene (THB) by molecular layer deposition (MLD). UV-VIS, Using Infrared spectrum and X-ray photoelectron spectroscopy confirm that Zinc and THB hybrid film (ZnTHB) consist of Zn-O and THB - oxide units and the micro structure and composition of hybrid film. hat the sequential surface reactions of diethyl zinc and ethylene glycol are sufficiently self-limiting and saturating to enable well-controlled MLD growth. Transmission electron microscopy image shows lamination growth of ZnTHB film according to cycle.

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VARTM 법으로 제작한 탄소-유리/에폭시 하이브리드 적층재의 인장 특성 (Tensile Properties of Carbon-Glass/Epoxy Hybrid Laminates Produced by VARTM)

  • 김연직
    • 대한금속재료학회지
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    • 제49권10호
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    • pp.760-765
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    • 2011
  • This paper presents a study of the tensile behavior of carbon and glass fiber reinforced epoxy hybrid laminates manufactured by vacuum assisted resin transfer molding (VARTM). The objective of this study was to develop and characterize carbon fiber reinforced plastic hybrid composite material that is low cost and light-weight and that possesses adequate strength and stiffness. The effect of position and content of the glass fabric layer on the tensile properties of the hybrid laminates was examined. The strength and stiffness of the hybrid laminates showed a steady decrease with an increase of the glass fabric content this decrease was almost linear. Fracture strain of these laminates showed a slight increasing trend when glass fabric content was increased up to 3 layers, but at a glass fabric content > 3 layers the strain was almost constant. When glass fabric layers were at both outer surfaces, the hybrid laminate exhibited a slightly higher tensile strength and elastic modulus due to the small amount of glass yarn pull-out.

태양열/공기열 복합 집열기를 가지는 하이브리드 히트펌프 시스템의 열성능에 관한 연구 (Study on the Thermal Performance of a Solar Assisted Heat Pump System with a Hybrid Collector)

  • 도규형;최병일;한용식;김명배;김태훈
    • 한국수소및신에너지학회논문집
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    • 제27권2호
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    • pp.182-191
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    • 2016
  • In the present work, a solar assisted heat pump (SAHP) system with a hybrid collector was analyzed. For this, a simplified thermodynamic model was developed. Based on the proposed model, the heat transfer rate, COP, and the annual operating hour of the SAHP system were estimated. The effect of the variation of system design parameters on the performance of the system was also examined. From the results, the performance was improved with increasing the effectiveness of heat exchangers and decreasing the difference between the evaporation temperature and the outlet brine temperature of the hybrid collector loop. Finally, the performance of SAHP system with a hybrid collector was compared with that of conventional serial and parallel SAHP systems. The SAHP system with a hybrid collector was substantially better than a series system and slightly worse than a parallel system for both the yearly averaged heat transfer rate and COP. However, the annual operating hour of the SAHP system with a hybrid collector was much better than that of a parallel system.

수분수집을 위한 초발수/초친수 복합 표면 제작: 그라비아 옵셋 프린팅과 콜로이달 리소그래피 공정 (Fabrication of a Hybrid Superhydrophobic/superhydrophilic Surface for Water Collection: Gravure Offset Printing & Colloidal Lithography)

  • 지승묵;김인영;김은희;정지은;김완두;임현의
    • 한국정밀공학회지
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    • 제29권1호
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    • pp.19-24
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    • 2012
  • We demonstrate the desert beetle back mimicking hybrid superhydrophilic/superhydrophobic patterned surface by using the combination method of colloidal lithography and gravure offset printing for nano and micro patterning, respectively. The two methods are cost-effective and industrially available techniques compared to the other nano/micro patterning methods. To verify the water collecting function of the hybrid surface, the water condensation behavior is investigated on the chilled surface in ambient temperature and high humidity. Due to the synergetic effect of drop and film wise condensation, the hybrid superhydrophobic/superhydrophilic surface shows the higher efficiency than one of single wettability surfaces. The work is underway to get the good patterns of hybrid surfaces for water collecting from the dew or fog.

GZO/Metal/GZO 하이브리드 구조 투명 전도막의 전기적, 광학적 특성; Ag, Cu, Al, Zn 금속 삽입층의 효과 (Electrical and Optical Properties of Transparent Conducting Films having GZO/Metal/GZO Hybrid-structure; Effects of Metal Layer(Ag, Cu, Al, Zn))

  • 김현범;김동호;이건환;김광호
    • 한국표면공학회지
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    • 제43권3호
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    • pp.148-153
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    • 2010
  • Transparent conducting films having a hybrid structure of GZO/Metal/GZO were prepared on glass substrates by sequential deposition using DC magnetron sputtering. Silver, copper, aluminum and zinc thin films were used as the intermediate metal layers in the hybrid structure. The electrical and optical properties of hybrid transparent conducting films were investigated with varying the thickness of metal layer or GZO layers. With increasing the metal thickness, hybrid films showed a noticeable improvement of the electrical conductivity, which is mainly dependent on the electrical property of the metal layer. GZO(40 nm)/Ag(10 nm)/GZO(40 nm) film exhibits a resistivity of $5.2{\times}10^{-5}{\Omega}{\cdot}cm$ with an optical transmittance of 82.8%. For the films with Zn interlayer, only marginal reduction in the resistivity was observed. Furthermore, unlike other metals, hybrid films with Zn interlayer showed a decrease in the resistivity with increasing the GZO thickness. The optimal thickness of GZO layer for anti-reflection effect at a given thickness of metal (10 nm) was found to be critically dependent on the refractive index of the metal. In addition, x-ray diffraction analysis showed that the insertion of Ag layer resulted in the improvement of crystallinity of GZO films, which is beneficial for the electrical and optical properties of hybrid-type transparent conducting films.

시베리아 철갑상어(Acipenser baerii) 암컷과 러시아 철갑상어(Acipenser gueldenstaedtii) 수컷간 유도된 잡종 자어의 행동 발달 및 주광성 특징 (Ontogenetic Behavior and Phototactic Properties of Interspecific Hybrid Prolarvae Produced by Crossing Female Siberian Sturgeon Acipenser baerii and Male Russian Sturgeon Acipenser gueldenstaedtii)

  • 남윤권;김은정
    • 한국수산과학회지
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    • 제52권3호
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    • pp.274-282
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    • 2019
  • Female Siberian sturgeon Acipenser baerii were crossed with male Russian sturgeon A. gueldenstaedtii and the development, ontogenetic behavior, and phototactic characteristics of the resultant hybrid prolarvae were examined. The fertilization rate of the hybrid group was similar to that of Siberian sturgeon (the maternal species), and the overall developmental characteristics of hybrid embryos were not significantly different from those of either parental species. The time window from first hatch to the completion of hatching was wider in Russian sturgeon than in Siberian and hybrid sturgeon groups. The prolarval viability of the hybrid group was similar to that of the maternal species, and significantly higher than that of the paternal species. Hybrid prolarvae displayed ontogenetic behavioral patterns that were quite similar to those of Siberian sturgeon. In an illumination preference test, hybrid prolarvae displayed significant positive phototaxis, similar to the maternal species, and clearly distinct from the negative phototactic character of the paternal species. Taken together, our data indicate that the prolarval traits of hybrid sturgeon from this cross more closely resemble those of the maternal than the paternal species.

자기치유 공학재료: I. 유기 재료 (Self-healing Engineering Materials: I. Organic Materials)

  • 최은지;왕징;윤지환;심상은;윤주호;김일
    • 청정기술
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    • 제17권1호
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    • pp.1-12
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    • 2011
  • 과학자와 공학자들은 끊임없이 금속, 합금, 고분자, 세라믹 등의 공학재료의 성질을 계속해서 변화하는 사회의 요구에 부응하는 방향으로 개선하여 왔다. 인조 공학재료는 일반적으로 기계적 성질이 우수하여, 자연 재료의 기계적 성질보다 우수한 경우가 많다. 그러나, 이와 같은 공학 재료는 자연계에서 흔히 볼 수 있는 자기 치유능력, 즉 고의적인 인간의 접촉을 거치지 않고도 미세균열을 제거하는 능력이 부족하다. 자연에서 관측할 수 있는 손상관리 패러다임은 여러 가지 종류의 공학재료의 고유성질을 잘 고려하면 인조공학 재료에서도 성공적으로 재현할 수 있다. 특히 적절한 화학반응과 분자간력을 응용하면 고분자, 아이오노머, 복합체와 같은 유기재료에 적용할 수 있는 다양한 자기치유 방법을 개발할 수 있다.

High performance Organic-Inorganic Hybrid Materials for Application in OLED Barrier Coating

  • Jung, Kyung-Ho;Yun, Chang-Hun;Bae, Jun-Young;Yoo, Seung-Hyup;Bae, Byeong-Soo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.806-809
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    • 2009
  • Epoxy functionalized organic-inorganic hybrid materials (hybrimers) were synthesized by sol-gel reaction for application in OLED barrier coating. By using the calcium degradation method, the oxygen transition rate (OTR) and water vapor transition rate (WVTR) measured so far is $10^{-2}cc/m^2$-day for oxygen and $10^{-1}g/m^2$-day for water molecules with single hybrimer coating film, respectively. Encapsulated OLED devices have life time of 14hrs of a single hybrimer barrier coating and 29hrs of hybrimer/inorganic double barrier coatings at $25^{\circ}C$ and 60% relative humidity.

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