• Title/Summary/Keyword: spacers

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White organic light-emitting diodes with various spacers inserted between blue and red emissive layers (Spacer에 따른 백색 유기 전기 발광 소자의 전기적 특성에 관한 연구)

  • Park, Jung-Hyun;Lee, Seok-Jae;Kim, Gu-Young;Seo, Ji-Hyun;Seo, Ji-Hoon;Yoon, Seung-Soo;Lee, Seung-Hee;Kim, Young-Kwan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.402-403
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    • 2007
  • High-efficiency white organic light-emitting diodes (WOLEDs) were fabricated with two emissive layers and a spacer was sandwiched between two phosphorescent dyes which were, bis(3,5-Difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl) iridium III (FIrpic) as the blue emission and bis(5-acetyl-2-phenylpyridinato-N,C2') acetylacetonate $((acppy)_2Ir(acac))$ as the red emission. This spacer effectively prevented a triple-triple energy transfer between the two phosphorescent emissive layers with blue and red emission that was showed a improved lifetime. The white device showed Commission Internationale De L'Eclairage $(CIE_{x,y})$ coordinates of (0.33, 0.42) at $22400\;cd/m^2$, a maximum luminance of $27300\;cd/m^2\;at\;0.388\;mA/cm^2$, and a maximum luminous efficiency of 26.9 cd/A.

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A Study on the Characteristics of Anion Exchange Membrane According to Aliphatic Alkyl Chain Spacer Length Introduced into Branched Poly (Arylene Ether Sulfone) (수지상 폴리(알릴렌 이써 설폰)에 도입된 지방족 알킬사슬 연결자길이에 따른 음이온교환막의 특성 연구)

  • KIM, HYUN JIN;YOO, DONG JIN
    • Journal of Hydrogen and New Energy
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    • v.33 no.3
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    • pp.209-218
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    • 2022
  • Recently, research on the development of anion exchange membranes (AEMs) has received considerable attention from the scientific community around the world. Here, we fabricated a series of AEMs with branched structures with different alkyl spacers and conducted comparative evaluations. The introduction of these branched structures is an attempt to overcome the low ionic conductivity and stability problems that AEMs are currently facing. To this end, branched polymers with different spacer lengths were synthesized and properties of each membrane prepared according to the branched structure were compared. The chemical structure of the polymer was investigated by proton nuclear magnetic resonance, Fourier transform infrared, and gel permeation chromatography, and the thermal properties were investigated using thermogravimetric analysis. The branched anion exchange membrane with (CH2)3 and (CH2)6 spacers exhibited ionic conductivities of 8.9 mS cm-1 and 22 mS cm-1 at 90℃, respectively. This means that the length of the spacer affects the ionic conductivity. Therefore, this study showing the effect of the spacer length on the ionic conductivity of the membrane in the polymer structure constituting the ion exchange membrane is judged to be very useful for future application studies of AEM fuel cells.

An integrated elastomer substrate with a lens array and pixel elements for three-dimensional liquid crystal displays

  • Hong, Jong-Ho;Kim, Yeun-Tae;Kim, Yun-Hee;Lee, Byoung-Ho;Lee, Sin-Doo
    • Journal of Information Display
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    • v.13 no.2
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    • pp.55-59
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    • 2012
  • In this paper, a concept of an integrated elastomer substrate for a three-dimensional (3D) liquid crystal display based on the integral-imaging method is presented. The elemental lens array and columnar spacers were integrated into one of the two substrates, an elastomer substrate, through an imprinting process. The integrated elastomer substrate was capable of maintaining the uniform liquid crystal (LC) cell gap and promoting homeotropic LC alignment without any surface treatment. The monolithic approach reported herein will provide a key component for 3D displays with enhanced portability through a more than 40% weight reduction compared with the conventional integral-imaging method.

Study on Bubble Behavior with the Simulated Electrode System of High Temperature Superconducting Coils for Electric Power System (전력용 고온초전도 코일 모의전극계에서의 기포거동에 관한 연구)

  • 석복렬;김종구
    • Progress in Superconductivity and Cryogenics
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    • v.3 no.1
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    • pp.16-21
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    • 2001
  • Bubble behavior is studied with an electrode system which consists of coaxial spiral coil-to-cylindrical electrode with an insulation barrier and spacers and is immersed in liquid nitrogen for simulation of insulation environments in high temperature superconducting(HTS) coils The results show that the bubble behavior Is affected severely by electric field: (1) under low applied voltage bubbles rise by buoyancy, but at higher applied voltage they are trapped in a lower electric field region below the coil electrode, and (2) the trapped bubble flows along the downside of coil electrode if no obstruction is in a groove between coil turns. but it splashes out of the groove after its growing if the obstruction such as spacer-exists.

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Quantum Chemical Designing of Novel Organic Non-Linear Optical Compounds

  • Mahmood, Asif;Abdullah, Muhammad Imran;Nazar, Muhammad Faizan
    • Bulletin of the Korean Chemical Society
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    • v.35 no.5
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    • pp.1391-1396
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    • 2014
  • In the present study, ten metal free non-linear optical (NLO) compounds have been designed. These compounds have designed by structural modification of (2-cyano-5-(4-(phenyl(4-vinylphenyl)amino)phenyl) penta-2,4-dienoic acid (TC4). Density functional theory was used for structure optimization and determination of photo-physical properties. These compounds contain triphenylamine as electron-donor and cyanoacrylic acid as acceptor. Five ${\pi}$-spacers are used to connect the donor and acceptor. Two auxiliary donors are also used to assist the donor. Results of this study indicate that stronger electron-donating auxiliary groups and longer ${\pi}$-conjugation enhance NLO response. Major absorption peaks of all systems were in the visible region. These absorption peaks are associated with the ${\pi}-{\pi}^*$ transitions of the entire molecule. From calculations it is clear that all system will be good NLO material. The present calculations will provide new ways for experimentalists to synthesize high-performance NLO material.

Isolation and Identification of Fungi for Decolorization of Synthetic Dyes

  • Lee, Jang-Hoon;Nam, Youn-Ku;Kwon, Hyuk-Ku
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2005.12a
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    • pp.95-102
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    • 2005
  • For decolorization of synthetic dyes, Isolate fungi were investigated for the decolorization of 8 industrial dyes. One fungus isolated from textile wastewater collected from Banweol industrial complex, Korea showed excellent ability for removing synthetic dyes. Internal Transcribed Spacers (ITS) sequencing result was confirmed as the new Basidomycetes species. HUE05-1 The optimal decolorizaton conditions were pH5, 30$^{\circ}C$ and aerobic condition. HUE05-1 was completely decolorized all dyes in both solid and liquid condition. The result is decolorization effect at Reactive Orange 16; 97.12%, Reactive Blue 19; 92.09%, Reactive Blue 49; 97.04%, Reactive Yellow 145; 95.53%, Acid Orange 10; 99.18%, Acid Violet 43; 98.73%, Acid Blue 350; 94.71%, Disperse Blue 106; 90.07%.

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Scytalidium parasiticum sp. nov., a New Species Parasitizing on Ganoderma boninense Isolated from Oil Palm in Peninsular Malaysia

  • Goh, Yit Kheng;Goh, Teik Khiang;Marzuki, Nurul Fadhilah;Tung, Hun Jiat;Goh, You Keng;Goh, Kah Joo
    • Mycobiology
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    • v.43 no.2
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    • pp.107-117
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    • 2015
  • A mycoparasite, Scytalidium parasiticum sp. nov., isolated from the basidiomata of Ganoderma boninense causing basal stem rot of oil palm in Johor, Malaysia, is described and illustrated. It is distinct from other Scytalidium species in having smaller asci and ascospores (teleomorphic stage), longer arthroconidia (anamorphic stage), hyaline to yellowish chlamydospores, and producing a fluorescent pigment. The phylogenetic position of S. parasiticum was determined by sequence analyses of the internal transcribed spacers and the small-subunit ribosomal RNA gene regions. A key to identify Scytalidium species with teleomorphic stage is provided.

An Analysis on the Charge Distribution on the Spacer Using Dust Figure (Dust Figure를 이용한 스페이서상의 대전전하 분포해석)

  • Choi, Jae-Gu;Seo, Kil-Soo;Kim, Young-Bae;Kim, Ik-Soo
    • Proceedings of the KIEE Conference
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    • 1998.07e
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    • pp.1681-1683
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    • 1998
  • Unlike AC, DC dielectric characteristics of the spacer are very influenced by the quantity and the distribution of surface charges. A general impression of the distribution of surface charges is obtained if electrostatic powders are sprinkled over the surface. The distribution of surface charge was investigated with dust figures. Mechanism of charge accumulation on the spacer of $SF_6$ GIS has been studied using various types of model spacers which have different depths. As a result, it was found that charge accumulation was dominantly influenced by the normal component of the electric field and the usage of embedded electrodes was an adequate method to lessen field concentration around the triple junction. The guide of the optimum depth of the spacer was proposed.

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Design and analysis of a newly devised linear flexure bearing(KIMM-LFB) for small precision reciprocating machines (소형 정밀 왕복동기기용 선형 탄성 베어링 모델(KIMM-LFB)의 설계 및 해석)

  • Choi, S.K.;Park, S.J.;Hong, Y.J.;Kim, H.B.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.404-409
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    • 2002
  • A newly devised linear flexure bearing (KIMM-LFB) for reciprocating machines is disclosed having improved tight gas clearance maintaining capability for better system performance. KIMM-LFB is an integrated device comprising an axially moving diaphragm with circumferentially arranged arc-shaped flexure blades secured between rim and hub spacers, which turn out to have higher radial stiffness than the one with circumferential tangent cantilever flexure blades. It is expected for KIMM-LFB to play a key role in designing long life, special purpose reciprocating machines such as spacecraft borne cryogenic refrigerators (cryocoolers) by providing frictionless, non-wearing, linear movement and radial support for the machines as well as a gas clearance seal by maintaining extremely tight clearances between piston and cylinder.

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Sequence Analysis of Cochlodinium polykrikoides Isolated from Korean Coastal Waters Using Sequences of Internal Transcribed Spacers and 5.8S rDNA

  • Kim, Hak-Gyoon;Cho, Yong-Chul;Cho, Eun-Seob
    • Journal of the korean society of oceanography
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    • v.35 no.3
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    • pp.158-160
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    • 2000
  • The relativity of four isolates of C. polykrikoides was determined by comparative sequence analysis based on direct sequencing of PCR amplified ribosomal DNA (the internal transcribed spacer region and the 5.8S rDNA). Sequence comparisons indicated that four isolates had the same nucleotide sites in the ITS regions, as well as a total of 585 nucleotide length and 100% homology. The molecular data revealed that C. polykrikoides in Korean coastal waters show no genetical difference.

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