• 제목/요약/키워드: photochromic

검색결과 91건 처리시간 0.027초

광색변성 Spiroxazine계 색소의 합성과 응용 (Synthesis and Application of Photochromic Spiroxazine Dyes)

  • 손세모
    • 한국인쇄학회지
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    • 제10권1호
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    • pp.23-33
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    • 1992
  • The negative pressure distribution curves of the exit of printing nip were obtained by the transducer type tackometer. As the results, found that the elasticity of rubber rollers and pastic viscosity affect to the maximum negative and positive pressure but, the gap of the printing nip didn`t affects to the tack values of ink and ink film thickness. Ink spritting is accured by negative pressure and inks viscoelasticity. And the tack value is affect by properties of the vehicle component in the inks.

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Chiral liquid crystals in photonic device applications

  • Gleeson, Helen F.;Yoon, Hyung-Guen;Roberts, Nicholas W.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.105-108
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    • 2007
  • Chiral liquid crystals exhibit band-gap structures responsive to electrical and optical fields, providing wide-ranging opportunities for photonics applications. We discuss three aspects of this technology: optics of chiral nematic devices and removal of pitch jumps; optical switching of chiral nematic materials; and using novel phases in photonic devices.

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측면연마 광섬유형 자외선센서의 광강도 변화에 따른 감도특성 (Sensitivity Characteristics of Side-Polished Fiber Optic UV Sensor with Optical Intensity Variation)

  • 이동록;서규원;윤종국;조강민;강신원
    • 대한전자공학회논문지SD
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    • 제41권6호
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    • pp.53-58
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    • 2004
  • 광기능성 색소가 분산된 평면도파로 결합기와 측면연마된 광섬유를 이용한 자외선 센서를 제작하여 광강도 변화에 따른 감도특성을 측정하였다. 광변색성 색소인 스파이록사진이 분간된 폴리머를 평면도파로로 사용하였다. 조사되는 자외선의 강도와 시간에 의해 유효굴절률이 변화하는 성질을 이용하였다. 자외선 조사시간을 3 초와 5 초로 고정한 상태에서 자외선 조사강도를 점차 증가시켰을 때 센서감도가 자각 $1.21{\mu}W/mw$$2.75{\mu}W/mw$로 나타났다. 자외선 조사 강도에 따른 출력 광강도의 변화를 측정한 결과 자외선 강도가 클수록 출력 광강도도 증가하고 포화시간은 단축됨을 알 수 있었다.

Holographic Grating by Means of Polymer Liquid Crystals

  • Ikeda, Tomiki;Yoneyama, Satoshi;Yamamoto, Takahiro;Hasegawa, Makoto
    • Journal of Information Display
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    • 제2권3호
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    • pp.6-12
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    • 2001
  • Formation of intensity gratings was studied with two s-polarized (s+s) configuration in polymer liquid crystals (PLCs) containing a photochromic moiety (azobenzene) and a mesogenic unit (tolane, T-AB; cyanobiphenyl, CB-AB) by photoinduced alignment of PLCs. Remarkable differences were observed between the two PLCs. T-AB showed a faster response to the change in the diffraction intensity than CB-AB. In T-AB, alignment change took place faster than that of CB-AB. By introducing the tolane unit at the side chain, we obtained a diffraction efficiency of 30 % in the Raman-Nath regime

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폴리비닐알코올 $H_6P_2W_{18}O_{62}$ hybrid membranes의 광색 및 열적 특성 (Photochromic and thermal properties of poly (Vinyl alcohol)/ $H_6P_2W_{18}O_{62}$ hybrid membranes)

  • Jian Gong;Kim, Hak-Yong;Lee, Duck-Rae;Bin Ding;Xiangdan Li
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 2002년도 봄 학술발표회 논문집
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    • pp.459-461
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    • 2002
  • A new class of materials based on organic and inorganic species combined at a molecule level has obtained more attention recently[1]. HPA(heteropolyacid) shows unmatched applied perspective in terms of synthesis chemistry, analysis chemistry, biology, medicine and materials science[2]. As a potential photochemical material, the hybrid system of HPA and polymer has been investigated. However, the design and synthesis of heteropolyacid-based hybrids, which are at the forefront of the materials chemistry research, is still in its infancy. (omitted)

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A photoswitch from conjugative aromatic polymers

  • Kwon, Tae-Chang;Kim, Yong-Jung;Kim, Yu-Na;Lee, Hyo-Jin;Rameshbabu Krishnamurthy;Sarwade Bhimrao D.;Kim, Eun-Kyoung
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.174-174
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    • 2006
  • By condensing two different functional monomers, highly fluorescent aromatic polymers were prepared to produce a conjugated- conjugated spacer-type copolymer or conjugated-non-conjugated spacer-type copolymer. As synthesized polymers were soluble in an organic solvent and showed significantly enhanced optical properties compared to its monomer. Variation in the monomer composition afforded polymers having multifunctionaility such as photochromic-fluorescent polymers. Transparent thin films of the polymer as a solid medium were prepared using spin coating method and fabricated as a photoswitch, which showed photo-induced conductivity switching properties depending on the core monomeric unit in the polymers.

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고주파 삼각파 여자법을 사용한 실시간 슬러그 유동 측정용 전자기유량계 (A Real-Time Measurement of Slug Flow Using Electromagnetic Flowmeter with High frequency Triangular Excitation)

  • 안예찬;차재은;김무환
    • 대한기계학회논문집B
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    • 제26권11호
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    • pp.1570-1577
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    • 2002
  • In order to investigate the characteristics of two-phase slug flow, an electromagnetic flowmeter with 240Hz triangular AC excitation was designed and manufactured. The signals and noise from the flowmeter were obtained, and analyzed in comparison with the observations with a high speed CCD camera. The uncertainty of the flowmeter under single-phase flow was $\pm$ 2.24% in real-time. For two-phase slug flow, electromagnetic flowmeter provided real-time simultaneous measurements of the mean film velocity around Taylor bubble and the relative location and the length of the bubble. Besides, it is an easier and cheaper method for measuring mean film velocity than others such as photochromic dye activation method or particle image velocimetry.

Simple Near-Field Optical Recording Using Bent Cantilever Probes

  • Kim, Jeong-Yong;Song, Ki-Bong;Park, Kang-Ho;Lee, Hyo-Won;Kim, Eun-Kyoung
    • ETRI Journal
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    • 제24권3호
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    • pp.205-210
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    • 2002
  • This paper describes our high-density near-field optical recording using bent cantilever fiber probes installed in an atomic force microscope. We conducted a near-field reading of nano-scale hole patterns with a 100 nm spatial resolution and a 25 ${\mu}m$/s scan speed; this implies a capability of a data reading density of 60 Gb/$in^2$ with a 0.25 kbps data transfer rate. In addition, we investigated re-writable near-field recording on photochromic diarylethene films. We successfully recorded erasable memory bits having a minimum width of 600 nm in a writing time as short as 30ms. We found that using a cantilever probe simplifies the setup and operation of the near-field optical recording system and may offer multifunctional recording capabilities.

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Synthesis and Characterizations of Bis-Spiropyran Derivatives

  • Lee, Sungmin;Ji, Seungwook;Kang, Youngjong
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3740-3744
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    • 2012
  • We synthesized three different derivatives of bis-spiropyran using simple organic reactions with high yields. BSP1, a derivative of bis-spiropyran having a connection at the position 6' and BSP2, a derivative of bis-spiropyran having a connection at the position 5 and BSP3, a derivative of bis-spiropyran containing a dithienylethene group between two spiropyran moieties were synthesized. The optical properties of BSPs were characterized. UV-Vis spectra showed that BSPs exhibit reversible photo-isomerization and the efficiency of photo-isomerization is highly dependent on the position of nitro group. BSPs having nitro group at para position of hydroxy group showed the higher efficiency of photo-isomerization that the one having nitro group at ortho position. The optical microscope images obtained under ultraviolet or visible light exposure demonstrated that the formation of nanorods can be reversibly controlled by optical signal.