• 제목/요약/키워드: novel materials

검색결과 1,879건 처리시간 0.028초

Novel Maskless Bumping for 3D Integration

  • Choi, Kwang-Seong;Sung, Ki-Jun;Lim, Byeong-Ok;Bae, Hyun-Cheol;Jung, Sung-Hae;Moon, Jong-Tae;Eom, Yong-Sung
    • ETRI Journal
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    • 제32권2호
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    • pp.342-344
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    • 2010
  • A novel, maskless, low-volume bumping material, called solder bump maker, which is composed of a resin and low-melting-point solder powder, has been developed. The resin features no distinct chemical reactions preventing the rheological coalescence of the solder, a deoxidation of the oxide layer on the solder powder for wetting on the pad at the solder melting point, and no major weight loss caused by out-gassing. With these characteristics, the solder was successfully wetted onto a metal pad and formed a uniform solder bump array with pitches of 120 ${\mu}m$ and 150 ${\mu}m$.

Recent Trends in Ferrous PM Materials in Japan

  • Takajo, Shigeaki
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 1993년도 추계학술강연 및 발표대회강연 및 발표논문 초록집
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    • pp.4-4
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    • 1993
  • Ferrous powder metallurgy in Japan has developed in the last four decades, where every decade is featured by certain breakthroughs in materials. The progress in PM materials is closely related to newly developed powders. Low alloy steel powders for high strength PM components are grouped into three types: Ni and/or Mo containing completely alloyed powders, Ni containing partially alloyed powders, and Cr containing completely alloyed powders. Every type has its special characteristics. The tensile strength of PM materials is improved up to 2 GPa. The hardness is also increased to exceed 500 HV with normal hardening methods, and 700 HV with novel surface treatment techniques. The present maximum of fatigue strength is 550 MPa, and that of impact energy is 100 J. Novel PM materials with improved properties are applied to a variety of automobile and other components: power steering pumps, rocker anns, valve guides and inserts, bearings, torque sensors, etc. The future outlook for the ferrous PM is Quite positive, and the industry is expected to show renewed growth by applying many types of alloy steel powders and new ferrous PM materials.

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Shear behavior of a demountable bolted connector in steel-UHPC lightweight composite structures

  • Gu, Jin-Ben;Wang, Jun-Yan
    • Structural Engineering and Mechanics
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    • 제81권5호
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    • pp.551-563
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    • 2022
  • Bolted connector could be an alternative to replace the conventional welded headed stud in steel-ultra high performance concrete (UHPC) lightweight composite structures. In this paper, a novel demountable bolted shear connector, consisting of a high-strength bolt (HSB) and a specially-designed nut which is pre-embedded in a thin UHPC slab, is proposed, which may result in the quick installation and disassembly, due to the mountable, demountable and reusable features. In order to study the shear behavior of the new type of bolted shear connector, static push-out tests were conducted on five groups of the novel demountable bolted shear connector specimens and one group of conventional welded headed stud specimen for comparison. The effect of the bolt shank diameter and aspect ratio of bolt on failure mode, shear stiffness, peak slip at the steel-UHPC interface, shear strength and ductility of novel bolted connectors is investigated. Additionally, design formula for the shear strength is proposed to check the suitability for assessment of the novel demountable bolted shear connectors.

2단 실린더형 싸이클론의 물 및 오일 액적 제거 성능 분석 연구 (Evaluation of removal performance of a novel two-stage cylinder type cyclone against water and oil droplets)

  • 김수민;김학준;김명준;한방우;우창규;김용진
    • 한국입자에어로졸학회지
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    • 제13권3호
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    • pp.119-125
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    • 2017
  • A novel two stage cylindrical cyclone was developed for a 3 phase separator in shale oil production industry. The cyclone performance was compared with a cone type cyclone and multi cyclone at the same experimental condition using water and oil mists generated by a humidifier and atomizer at the flow rate 1 to $2m^3/min$. The removal efficiency of total suspended water droplets by the novel cyclone, calculated using inlet and outlet concentrations measured by an optical particle counter, was 99% which is higher than 90% of oil droplet removal efficiency at $2m^3/min$. It might be due to the evaporation of small water droplets during the tests. The water and oil droplet removal performance of the novel cyclone based on the quality factor which is a function of pressure drop and removal efficiency was the highest among three cyclones. The results indicate that the cyclone could be an economical device to remove water and oil mists from shale gas generation processes where a huge three phase separator is commonly used.

Recent Progress in Luminescent Lanthanide Complexes for Advanced Photonics Applications

  • Kim, Hwan-Kyu;Oh, Jae-Buem;Baek, Nam-Seob;Roh, Soo-Gyun;Nah, Min-Kook;Kim, Yong-Hee
    • Bulletin of the Korean Chemical Society
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    • 제26권2호
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    • pp.201-214
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    • 2005
  • We have designed and developed novel luminescent lanthanide complexes for advanced photonics applications. Lanthanide(III) ions (Ln$^{3+}$) were encapsulated by the luminescent ligands such as metalloporphyrins and naphthalenes. The energy levels of the luminescent ligands were tailored to maintain the effective energy transfer process from luminescent ligands to Ln$^{3+}$ ions for getting a higher optical amplification gain. Also, key parameters for emission enhancement and efficient energy transfer pathways for the sensitization of Ln$^{3+}$ ions by luminescent ligands were investigated. Furthermore, to enhance the optophysical properties of novel luminescent Ln$^{3+}$ complexes, aryl ether-functionalized dendrons as photon antennas have been incorporated into luminescent Ln$^{3+}$ complexes, yielding novel Ln(III)-cored dendrimer complex. The novel Ln(III)-cored dendrimer complex has much higher PL intensity than the corresponding simple complex, due to the efficient site-isolation effect. In this article, we will deal with recent progress in the synthesis and photophysical studies of inert and stable luminescent Ln$^{3+}$ complexes for advanced photonics applications. Also, our review will include the exploratory investigation of the key parameters for emission enhancement and the effective energy transfer pathways from luminescent ligands to Ln$^{3+}$ ions with Ln(III)-chelated prototype complexes.

Development of a Novel Short Synthetic Antibacterial Peptide Derived from the Swallowtail Butterfly Papilio xuthus Larvae

  • Kim, Seong Ryul;Choi, Kwang-Ho;Kim, Kee-Young;Kwon, Hye-Yong;Park, Seung-Won
    • Journal of Microbiology and Biotechnology
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    • 제30권9호
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    • pp.1305-1309
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    • 2020
  • Insects possess biological defense systems that can effectively combat the invasion of external microorganisms and viruses, thereby supporting their survival in diverse environments. Antimicrobial peptides (AMPs) represent a fast-acting weapon against invading pathogens, including various bacterial or fungal strains. A 37-residue antimicrobial peptide, papiliocin, derived from the swallowtail butterfly Papilio xuthus larvae, showed significant antimicrobial activities against several human pathogenic bacterial and fungal strains. Jelleines, isolated as novel antibacterial peptides from the Royal Jelly (RJ) of bees, exhibit broad-spectrum protection against microbial infections. In this study, we developed a novel antimicrobial peptide, PAJE (RWKIFKKPFKISIHL-NH2), which is a hybrid peptide prepared by combining 1-7 amino acid residues (RWKIFKK-NH2) of papiliocin and 1-8 amino acid residues (PFKISIHL-NH2) of Jelleine-1 to alter length, charge distribution, net charge, volume, amphipaticity, and improve bacterial membrane interactions. This novel peptide exhibited increased hydrophobicity and net positive charge for binding effectively to the negatively charged membrane. PAJE demonstrated antimicrobial activity against both gram-negative and gram-positive bacteria, with very low toxicity to eukaryotic cells and an inexpensive process of synthesis. Collectively, these findings suggest that this novel peptide possesses great potential as an antimicrobial agent.

Novel host and electron blocking materials for efficient and long lifetime phosphorescent OLEDs

  • Vestweber, Horst;Gerhard, Anja;Kaiser, Joachim;Heil, Holger;Kroeber, Jonas;Pflumm, Christof;Stoessel, Philipp;Joosten, Dominik;Buesing, Arne;Fortte, Rocco;Parham, Amir;Boehm, Edgar
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.925-927
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    • 2008
  • In order to improve the performance in green phosphorescent OLED devices, Merck has developed novel host and electron blocking materials. The newly developed host materials improve the device lifetime by a factor of 3. The newly developed electron blocking materials having not only electron but also exciton barrier properties increase the efficiency of the device by a factor of 1.4. Comparable results were achieved in phosphorescent red systems with further host materials.

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Synthesis and Characterization of Novel Blue Materials based on Anthracene Derivatives for High Efficient OLED

  • Zhao, QingHua;Jung, Sung-Ouk;Kang, Dong-Min;Kim, Yun-Hi;Kwon, Soon-Ki
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.439-442
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    • 2007
  • Novel blue materials based on anthracene derivatives were synthesized by Grignard reaction, the Suziki coupling reaction, etc. They showed excellent thermal stability and emitted bright blue light, which will been used for OLED and expected to obtain high efficiency and good color purity.

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Post-processing of Direct Teaching Trajectory in Industrial Robots

  • Choi, Tae-Yong;Park, Chan-Hun;Do, Hyun-Min;Chung, Kwang-Cho;Park, Dong-Il;Kyung, Jin-Ho
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제12권3호
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    • pp.256-262
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    • 2012
  • Direct teaching of the industrial robot is a novel technique to easily teach manipulators. However, teaching data by human hand cannot help having large noise errors ranging from low to high frequency. To use teaching data, post-processing to correct the teaching trajectory is required. Here, a novel shape-based trajectory correction method to rebuild teaching data with the feature information of curvature and velocity is proposed. The proposed method is tested on square and circular objects.