• 제목/요약/키워드: planar cell

검색결과 213건 처리시간 0.027초

A new derivative of phorbaketals isolated from a Marine Sponge Phorbas species

  • Hwang, Buyng-Su;Yang, Cao;Rho, Jung-Rae
    • 한국자기공명학회논문지
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    • 제15권2호
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    • pp.128-136
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    • 2011
  • A new sesterterpenoid, phorbaketal derivative, was isolated from the marine sponge Phorbas species. Its planar structures was completely determined from a combination of extensive 1D and 2D NMR experiments and MS data, and also the stereochemistry on the chiral centers were established by the ROESY experiment and the comparison with the $^1H$ and $^{13}C$ chemical shifts of the known phorbaketal compounds. This compound 1 moderately showed cytotoxicity effect against hepatoma cancer HepG2 cell.

트렌치 케이트 하단의 게이트 산화막 확장을 통한 트렌치 IGBT의 항복전압 향상에 대한 연구 (A Study on Breakdown Voltage Improvement of the Trench IGBT by Extending a Gate Oxide Region beneath the Trench Gate)

  • 이재인;경신수;최종찬;성만영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.74-75
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    • 2008
  • TIGBT has some merits which are lower on-state voltage drop and smaller cell pitch, but also has a defect which is relatively lower breakdown voltage in comparison with planar IGBT. This lower breakdown voltage is due to the electric field which is concentrated on beneath the vertical gate. Therefore in this paper, new trench IGBT structure is proposed to improve breakdown voltage In the new proposed structure, a narrow oxide beneath the trench gate edge where the electric field is concentrated is extended into rectangular shape to decrease the electric field. As a result, breakdown voltage is improved to 23%.

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Surface Encoder Based on the Half-shaded Square Patterns (HSSP)

  • Lee, Sang-Heon;Jung, Kwang-Suk;Park, Eui-Sang;Shim, Ki-Bon
    • International Journal of Precision Engineering and Manufacturing
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    • 제9권3호
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    • pp.82-84
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    • 2008
  • A surface encoder based on the Half-shaded square pattern (HSSP) is presented. The HSSP working as reference grid is composed of the straight lines which are easy to be fabricated and make measuring time short. Since the periodic cell is separated in ON/OFF by the $45^{\circ}$ straight line, the duration from the starting point of scanning to the first rising edge and the duty cycle of the pulse train vary with respect to the position of the starting point. And the relationship between X and Y position and the duration, and duty cycle is described in the simple linear equation. Therefore, it is possible to measure X and Y position with the measured duration and duty cycle without calculating load. Through the test set-up, the feasibility of the proposed surface encoder was verified. Also the future works for improvement of performance were suggested.

Crystal Structure Analysis of N,N'-bis(3-chloro-2-methylsalicylidene)-1,4-butanediamine

  • Sharmila, P.;Rajesh, R.;Venkatesan, R.;Ganapathy, Jagadeesan;Aravindhan, S.
    • 통합자연과학논문집
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    • 제9권4호
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    • pp.255-260
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    • 2016
  • The crystal structure of the saliciline derivatives N,N'-bis(3-chloro-2-methylsalicylidene)-1,4-butanediamine ($C_{20}H_{22}Cl_2N_2O_2$) has been determined from single crystal X-ray diffraction data. In the title compound crystallizes in the triclinic space group $P{\bar{i}}$ with unit cell dimension $a=4.6085(3){\AA}$, $b=5.9747(3){\AA}$ and $c=5.9747(3){\AA}$ [${\alpha}=83.889(4)^{\circ}$, ${\beta}=86.744(5)^{\circ}$ and ${\gamma}=82.085(5)^{\circ}$]. The title compound is essentially planar conformation. The compound lies across a crystallographic inversion centre and adopts E configurations with respect to the C-N bonds. The crystal packing of the molecules of compound is stabilized through weak O-H...N intra molecular interactions

Crystal Structure Analysis of 4-Chloro-2{[(2-hydroxy-5-methylphenyl)amino]methyl}5-methylphenol

  • Sharmila, P.;Rajesh, R.;Venkatesan, R.;Ganapathy, Jagadeesan;Aravindhan, S.
    • 통합자연과학논문집
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    • 제9권4호
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    • pp.261-267
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    • 2016
  • The crystal structure of the saliciline derivatives 4-chloro-2{[(2-hydroxy-5-methylphenyl)amino]methyl}5-methylphenol ($C_{15}H_{15}ClNO_2$) has been determined from single crystal X-ray diffraction data. In the title compound crystallizes in the monoclinic space group P21/c with unit cell dimension $a=11.5241(2){\AA}$, $b=8.733(2){\AA}$ and $c=13.649(2){\AA}$ [${\alpha}=90^{\circ}$, ${\beta}=130.876(2)^{\circ}$ and ${\gamma}=90^{\circ}$]. the title compound are essentially planar conformation. The compound lies across a crystallographic inversion centre and adopts E configurations with respect to the C-N bonds. The crystal packing of the molecules of compound is stabilized through weak O-H...O inter molecular interactions.

Nanodome-patterned Transparent Conductor for Highly Responsive Photoelectric Device

  • 홍승혁;윤주형;박형호;강길모;서철원;김준동
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.458.1-458.1
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    • 2014
  • An effective light-managing structure has been achieved by using a nano-imprint method. A transparent conductor of indium-tin-oxide (ITO) was periodically nanodome-shaped to have a height of 200 nm with a diameter of 340 nm on a p-type Si substrate. This spontaneously formed a heterojunction between the ITO layer and Si substrate and effectively reduced the light-reflection. The ITO nanodome device response was significantly enhanced to 6010 from the value of 72.9 of a planar ITO film. The transparent conducting ITO nanodome structure efficiently manipulates the incident light driving into the light-absorber and can be applied in various photoelectric applications.

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Salternamide E from a Saltern-derived Marine Actinomycete Streptomyces sp.

  • Kim, Seong-Hwan;Shin, Yoonho;Lee, Sang Kook;Shin, Jongheon;Oh, Dong-Chan
    • Natural Product Sciences
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    • 제21권4호
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    • pp.273-277
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    • 2015
  • Comprehensive chemical analysis of extracts and fractions of marine actinomycete strains led to the discovery of a new minor secondary metabolite, salternamide E (1), from a saltern-derived halophilic Streptomyces strain. The planar structure of salternamide E (1) was elucidated by a combinational analysis of spectroscopic data including NMR, MS, UV, and IR. The absolute configuration of salternamide E (1) was determined by circular dichroism spectroscopic analysis. Salternamide E displayed weak cytotoxicity against various human carcinoma cell lines.

A Single Low Twisted Nematic Mode for a Transflective LCD with a Self-Integrated Retardation Layer

  • Kim, Jin-Yool;Na, Jun-Hee;Lee, Sin-Doo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.411-414
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    • 2005
  • We have developed a transflective liquid crystal display (LCD) with a single cell gap and a low twisted nematic (LTN) mode in combination with a self-integrated retardation layer. The retardation layer was made of UV curable liquid crystalline material in one step of photo masking process and has both the homeotropic and the planar parts. The proposed transflective configuration has advantages in a simple fabrication process, and the possibility for a single driving scheme due to the similarity between the transmittance and the reflectance.

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Multi-cube UV source 이용한 PDP에서 광학시뮬레이션의 정확성 개선에 관한 연구 (Improvement of the Accuracy of Optical Simulation Using by the Multi-cube UV Source in PDP Cells)

  • 강정원;엄철환
    • 반도체디스플레이기술학회지
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    • 제6권2호
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    • pp.41-44
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    • 2007
  • Optical simulation of the rear and front panel geometries were needed to improve the luminance and efficiency in PDP cells. The 3-dimensional optical code can be used to analyze the variation of geometries and changing of optical properties. In order to improve the accuracy of simulated results, a new UV source, called a multi-cubes UV source, was designed. To design the source, at first UV distribution was calculated with the plasma fluid code and then the UV distribution was transformed to the multi-cube structures in the optical code. Compared to the results from existing UV source, called a planar UV source, could be improved the accuracy of visible light distribution. Simulated results were also compared to the visible distribution measured with the ICCD in a real PDP cell.

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Photo polymerization-induced Hybrid Alignment of Nematic Liquid Crystal for Roll to Roll Fabrication

  • Kim, Kyoung-Sun;Kwon, Soon-Bum;Lee, Ji-Hoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.623-624
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    • 2009
  • Here we report a photo polymerization-induced hybrid alignment of a nematic liquid crystal cell which can be applied for a roll to roll fabrication process. Predominant polymerization in the vicinity of UV incident front induced a diffusion of monomers toward front slide and anisotropic polymer network was formed parallel to the polarization direction of the UV light. This induced planar alignment of liquid crystals at the front slide. Simultaneously, homeotropic alignment was induced at the bottom slide as the polymers are phase-separated from a bottom slide.

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