• 제목/요약/키워드: Nano-bio technology

검색결과 533건 처리시간 0.031초

UV 임프린팅 공정을 이용한 금속막 필터제작 (Fabrication of Metallic Nano-Filter Using UV-Imprinting Process)

  • 노철용;이남석;임지석;김석민;강신일
    • 소성∙가공
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    • 제14권5호
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    • pp.473-476
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    • 2005
  • The demand of on-chip total analyzing system with MEMS (micro electro mechanical system) bio/chemical sensor is rapidly increasing. In on-chip total analyzing system, to detect the bio/chemical products with submicron feature size, a filtration system with nano-filter is required. One of the conventional methods to fabricate nano-filter is to use direct patterning or RIE (reactive ion etching). However, those procedures are very costly and are not suitable fur mass production. In this study, we suggested new fabrication method for a nano-filter based on replication process, which is simple and low cost process. After the Si master was fabricated by laser interference lithography and reactive ion etching process, the polymeric mold was replicated by UV-imprint process. Metallic nano-filter was fabricated after removing the polymeric part of metal deposited polymeric mold. Finally, our fabrication method was applied to metallic nano-filter with $1{\mu}m$ pitch size and $0.4{\mu}m$ hole size for bacteria sensor application.

디젤연소가능 청정연료(ULSD, Bio-Diesel, DME)엔진의 극미세입자 정량화 및 촉매 영향 (Characteristics of Nano-particle Emitted by Auto-ignited Engine with ULSD, Bio-diesel and DME Fuel and Effects of Oxidation Catalyst on Its Reduction)

  • 이진욱;배충식
    • 한국자동차공학회논문집
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    • 제17권3호
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    • pp.81-89
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    • 2009
  • In this experimental study, the effects of clean alternative fuels compatible with diesel combustion on nano-sized particle emission characteristics were investigated in a 0.5L auto-ignited single-cylinder engine with a compression ratio of 15. Because the number concentration of nano-sized particles emitted by automotive engine, that are suspected of being hazardous to human health and environment, might increase with engine fuel considerably and recently attracted attention. So a ultra-low sulfur diesel(ULSD), BD100(100% bio-diesel) and Di-Methyl Ether(DME) fuels used for this study. And, as a particle measuring instrument, a fast-response particle spectrometer (DMS 500) with heated sample line was used for continuous measurement of the particle size and number distribution in the size range of 5 to 1000nm (aerodynamic diameter). As this research results, we found that this measurements involving the large proportion of particles under size order of 300nm and number concentration of $4{\times}10^9$ allowed a single or bi-modal distribution to be found at different engine load conditions. Also the influence of oxygen content in fuel and the catalyst could be a dominant factor in controlling the nano-sized particle emissions in auto-ignited engine.

$H_2/CO_2$ 혼합기체의 분리를 위한 PEI-PDMS 중공사 복합막 모듈의 다단 공정 연구 (Multi-stage Process Study of PEI-PDMS Hollow Fiber Composite Membrane Modules for $H_2/CO_2$ Mixed Gas Separation)

  • 이충섭;조은혜;하성용;정종태;임지원
    • 멤브레인
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    • 제23권1호
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    • pp.1-11
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    • 2013
  • 혼합가스에서 $CO_2$를 선택적으로 분리할 수 있는 poly (etherimide) (PEI)-poly (dimethylsioxane) (PDMS) 재질의 복합막 및 모듈을 제조하여 $CO_2/H_2$ 분리특성을 확인하였다. 제조된 중공사 복합막 모듈은 모듈의 단수에 따라 $25^{\circ}C$, 일정 압력에서 stage-cut별로 분리된 가스의 유량, 농도, $H_2$ 회수율, $CO_2$ 제거율 등의 성능을 측정하였으며, $H_2$ 회수율을 높이기 위해 1단 시험에서 2단 직렬시험과 3단 직렬 + 병렬 시험으로 단수를 증가시켜 시험하였다. 각각의 운전조건에 대한 결과들을 확인한 결과 3단 운전조건에서 stage-cut을 0.32로 하였을 때 Product가스의 $H_2$ 농도는 97%이었으며 그때의 $H_2$ 회수율은 85%이었다. 또한, $CO_2$ 제거율은 약 90%의 결과를 얻을 수 있었으며 재순환 가스의 농도는 공급 가스와 유사하게 얻을 수 있었다.

Organic-Inorganic Hybrid Nanoflowers as Potent Materials for Biosensing and Biocatalytic Applications

  • Tran, Tai Duc;Kim, Moon Il
    • BioChip Journal
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    • 제12권4호
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    • pp.268-279
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    • 2018
  • Flower-shaped organic-inorganic hybrid nanostructures, termed nanoflowers, have received considerable recent attention as they possess greatly enhanced activity, stability, durability, and even selectivity of entrapped organic biomolecules, which are much better than those from the conventional methods. They can be synthesized simply via co-incubation of organic and inorganic components in aqueous buffer at room temperature and yield hierarchical nanostructures with large surface-to-volume ratios, allowing for low-cost production by easy scale-up, as well as the high loading capacity of biomolecules without severe mass transfer limitations. Since a pioneering study reported on hybrid nanoflowers prepared with protein and copper sulfate, many other organic and inorganic components, which endow nanoflowers with diverse functionalities, have been employed. Thanks to these features, they have been applied in a diverse range of areas, including biosensors and biocatalysis. To highlight the progress of research on organic-inorganic hybrid nanoflowers, this review discusses their synthetic methods and mechanisms, structural and biological characteristics, as well as recent representative applications. Current challenges and future directions toward the design and development of multi-functional nanoflowers for their widespread utilization in biotechnology are also discussed.

Effect of MnO2 Addition on Microstructure and Piezoelectric Properties of 0.95(Na0.5K0.5)NbO3-0.05CaTiO3 Piezoelectric Ceramics

  • Kim, Jong-Hyun;Seo, In-Tae;Hur, Joon;Kim, Dae-Hyeon;Nahm, Sahn
    • 한국세라믹학회지
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    • 제53권2호
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    • pp.129-133
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    • 2016
  • $MnO_2$ was added to the $0.95(Na_{0.5}K_{0.5})NbO_3-0.05CaTiO_3$ (NKN-CT) ceramics in order to promote the densification and improve the poling efficiency by increasing the resistance of the specimens. Densification and abnormal grain growth occurred in the $MnO_2$-added NKN-CT ceramics sintered at $1020^{\circ}C$, indicating that $MnO_2$ assisted the liquid-phase sintering of these materials. $Mn^{3+}$ ions were considered to enter the A-site of the matrix, thereby producing the free electrons, which interacted with the holes resulting from the evaporation of alkali ions. This interaction results in an increase in the resistance of the specimens. The increased resistance improved the poling efficiency and, hence, the dielectric and piezoelectric properties of the NKN-CT ceramics. A few of the $Mn^{3+}$ ions that entered the B-site of the NKN-CT matrix led to a slight increase in the mechanical quality factor.

Info-Convergence Ceramic Nanosystems

  • Jin, Wenji;Park, Dae-Hwan
    • 한국세라믹학회지
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    • 제56권5호
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    • pp.421-434
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    • 2019
  • We face many fascinating and diverse challenges, the most important among which is to determine how to store a large amount of information with novel approaches. Info-convergence ceramic nanosystems, which combine ceramic materials science and information technology, may provide an attractive alternative. This review considers recent multidisciplinary advances in the development of info-convergence nanosystems based on ceramic materials and discusses various strategies under ceramic-based information systems with a special focus on materials and nanohybridization technologies. Ceramic materials have played diverse roles not only as the generic coding support, but also as the central coding substance. The review highlights the ceramic nanohybrid bio code and ceramic nanoparticle optical code for applications in tracking-and-traceability management, nano-forensics, anti-counterfeiting, and even communication, as well as the four steps of encoding, encrypting, decrypting, and decoding for the desired applications. Additionally, associated challenges, potential solutions, and perspectives for future developments in the field are discussed.