• 제목/요약/키워드: Photoirradiation

검색결과 19건 처리시간 0.024초

광학이성 유기단분자막 전류특성 (Current Properties Of Photoisomerization Organic Monolayer)

  • 김동관;강용철;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.487-490
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    • 1999
  • The Maxwell displacement current was generated from 4-octyl-4'-(5-carboxyl-pentamethyleneoxy)- azobenzene (denoted as 8A5H) monolayer Langmuir-Blodgett films prepared on Cr/Au-coated glass substrates due to trans-cis photoisomerization of 8A5H by application of alternate irradiation with UV light and Visible light. The displacement current was generated due to the trans-to-CIS photoisomerization by irradiation with ultraviolet light($\lambda_1$=360nm). Whereas the displacement current was generated in the opposite direction due to the cis-to-trans photoisomerization by photoirradiation with visible light($\lambda_2$=450nm). Finally, We concluded that Displacement current change according to power capacity photoirradiation, the more higher generate the more higher power capacity magnitude.

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아조벤젠 유기단분자의 광제어에 관한 연구 (A Study on the Light Control of Azobenzene Organic Monolayers)

  • 김성진;정헌상;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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    • pp.139-142
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    • 2000
  • Displacement current was generated in the light stimulus. Solution of azobenzene molecules (8A5H) have to character trans-to-cis. The Maxwell displacement current measuring technique has been applied for the investigation of azobenzene organic thin films under alternating photoirradiation with ultraviolet($\lambda_1$) and visible($\lambda_2$) light. also, As laser beam(630~670nm) investigate light response. As result, ultraviolet($\lambda_1$) and visible($\lambda_2$) light see photoisomerization response, but laser beam not appear photoisomerization in current that differ wave range reagent.

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Time-Resolved Photoexcitation Dynamics of Electrical Conductivity of Magnetic Organic Superconductor λ-(BETS)2Fe0.45Ga0.55Cl4

  • Sabeth, Farzana;Islam, Md. Serajul;Endo, Tadashi;Ohta, Nobuhiro
    • Rapid Communication in Photoscience
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    • 제4권1호
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    • pp.25-28
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    • 2015
  • The time-resolved photoexcitation dynamics of electrical conductivity of the magnetic organic superconductor ${\lambda}-(BETS)_2Fe_{0.45}Ga_{0.55}Cl_4$ has been studied with a nanosecond visible laser pulse at its three different phases, i. e., metallic phase, superconducting phase and insulating phase. A transient increase of the resistance is induced by photoirradiation at all the temperatures measured for all three phases, but the decay profile shows a significant temperature dependence. The relaxation rate in the metallic and insulating phase are different from each other, and the decay time is relatively faster and almost constant in the metallic phase. However, a prolongation of the relaxation time is observed at temperature just around the narrow superconducting phase. Nonbolometric (nonthermal) origin of the observed photoresponse of the electrical conductivity is confirmed in the superconducting phase.

아조벤젠 유기박막의 광자격 특성에 관한 연구 (A Study on the Light Stimulus Properties by Azobenzene Organic Thin Films)

  • 조수영;김성진;송진원;이순형;정헌상;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.41-44
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    • 1999
  • Displacement current was generated in the pressure stimulus and light stimulus. Solution of azobenzene molecules (8A5H) have to character trans-to-cis. Pressure stimulus generate in the pressure and current. light stimulus generate in the displasement current. The Maxwell displacement current measuring technique has been applied for the investigation of azobenzene organic thin films under alternating photoirradiation with ultraviolet(360nm) and visible (450nm) light. The displacement current was generated due to the trans-to-cis photoisomerization by irradiation with ultraviolet light(λ$_1$=360 nm) Whereas the displacement current was generated in the opposite direction due to the cis-to-trans photoisomerization by irradiation with visible light(λ$_2$=450nm). As result, To show twice reaction certainly phase transition in pressure. A first range generated from 24$\AA$$^2$ to 29$\AA$$^2$and second range generated from 20$\AA$$^2$to 24$\AA$$^2$. Also, cetainfy stimulus apper low pressure and high pressure in photoirradiation. To see different every moment phase transition.

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GROWTH INHIBITION OF Acanthamoeba BY HYDROPEROXYNAPHTALIMIDES UPON PHOTOIRRADIATION

  • Matsugo, Seiichi;Takeuchi, Rie;Takehara, Yoshimi;Tsuruhara, Takashi
    • Journal of Photoscience
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    • 제4권3호
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    • pp.127-132
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    • 1997
  • Acanthamoeba strains were photoirradiated in the presence of light-sensitive organic peroxides (hydroperoxynaphthalimide derivatives) including a Photo-Fenton reagent at 366 nm. The survival rates of Acantharnoeba strains determined after 20 h culture showed a significant decrease only upon photoirradiated conditions. The most effective hydroperoxynaphthalimides among these compounds was the bromohydroperoxynaphthalimide (Br-HPO II). The minimum inhibitory concentration (MIC) of Br-HPO II is 100 times lower than that of hydrogen peroxide.

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A Large Trans/cis Conversion Ratio In Redox-Conjugated Single-Light Reversible Isomerization of a Cobalt Complex with meta-Bipyridylazobenzene Ligands

  • Kume, Shoko;Kurihara, Masato;Nishihara, Hiroshi
    • 전기화학회지
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    • 제5권4호
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    • pp.189-191
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    • 2002
  • Reversible trans-cis isomerization of meta-bipyridylazobenzene coordinated to cobalt was achieved by a combination of photoirradiation with a single UV light source and a Co(II)/Co(III) redox reaction. The trans/cis conversion performance was significantly improved in the meta-form compared with the meta-form ligated to cobalt.

Artificial Radical Generating and Scavenging Systems: Synthesis and Utilization of Photo-Fenton Regent in Biological Systems

  • Matsugo, Seiichi
    • Journal of Photoscience
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    • 제9권2호
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    • pp.138-141
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    • 2002
  • A photo-labile compound which is bioinactive but, upon irradiation with light, yields bioactive species is called as "caged compound". Photolysis of caged compounds generating bioactive species, has become a general method to produce a desired amounts of bioactive species in the specific time interval at the desired place or area of the target biological systems. For this purpose, we designed and synthesized caged hydroxyl radical., "Photo-Fenton Reagent" NP-IIl. NP-IIl has a strong absorption maximum at 377 nm and yields hydroxyl radicals upon UV light irradiation. The antioxidant activity of the ${\alpha}$ -lipoic acid and other naturally occurring compounds has been examined by using NP-IIl as a molecular probe. For example, upon photoirradiation of NP-lII with BSA or apolipoprotein of human low density (LDL), the significant oxidative modifications were observed in both cases. The oxidation was completely suppressed in the presence of ${\alpha}$-lipoic acid, which clearly demonstrates the strong hydroxyl radical scavenging activity of ${\alpha}$-lipoic acid. Other applications of NP-lII will also be described

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광자극에 의한 수면상 단분자막의 특성변화 (Characteristics of monolayer in water by photoirradiation)

  • 구창권;송경호;박태곤;박근호;권영수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 C
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    • pp.1424-1427
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    • 1996
  • The pressure-area isotherm(${\pi}$-A isotherm) of 8A5H(4-octyl-4'-(5-Carboxyl-pentamethyleneoxy)-azobenzene) at the air/water interface were obtained. Using the Xe/Hg Xe 500w(93' model 68811), an activities of molecule at the air/water interface were certified. In addition, using a current-measuring technique, we investigated the abrupt changes of a current observed at the liquid-to-solid phase transition in a current-area (I-A) isotherm of a fatty acid monolayer at the air/water interface

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Ag-modified BiOX (X=Cl, Br and I) Plates for Photocatalytic Dye Removal

  • 이승원;최영인;이주헌;박요한;손영구
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.424.2-424.2
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    • 2014
  • Ag-modified BiOX (X=Cl, Br and I) nanoplates were synthesized by an ion-exchange reaction. We examined the fundamental properties by scanning electron microscopy (SEM), electron transmission microscopy (TEM), X-ray diffraction, UV-visible absorption, Fourier-transform infrared and photoluminescence spectroscopy. The adsorption and photocatalytic performances of the catalysts were tested with dyes under UV and visible light. A chemical scavenger method was employed to test the roles of active species (${\cdot}OH$, ${\cdot}O2-$ and h+) and understand photodegradation mechanism. Photoluminescence spectroscopy was used to examine ${\cdot}OH$ radical formation using terephthalic acid during photoirradiation.

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Photoinduced Charge-Transfer Association of Tetracyanoquinodimethane with Aminobiphenyls

  • Kim, Yong-Hee;Jung, Sang-Don;Chung, Myung-Ae;Song, Ki-Dong;Cho, Dae-Won
    • Bulletin of the Korean Chemical Society
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    • 제29권5호
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    • pp.948-952
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    • 2008
  • The molecular association of acceptors with electron donors is studied in the highly-polar solvent $CH_3CN$. Tetracyanoquinodimethane (TCNQ) forms a stable charge-transfer complex with donor molecules such as 4- aminobiphenyl (4-AB), benzidine (BD) and 2-aminobiphenyl (2-AB) with high association constants. The complexes of TCNQ with 4-AB or BD show new absorption bands at around 800 and 500 nm, which can be identified as reduced $TCNQ^{{\bullet}-}$ and $TCNQ^{2-}$ species, respectively. These bands grow quickly upon photoirradiation, implying that the charge-transfer complexes are easily formed in an excited state. Conversely, a small spectral manifestation of the charge transfer was observed in the case of 2-AB complex. It is demonstrated that the structural orientation between the geminate ion pairs could play an important role in building a stable complex.