• Title/Summary/Keyword: Bipyridine

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Dynamics of RNA Bacteriophage MS2 Observed with a Long-Lifetime Metal-Ligand Complex

  • Kang, Jung Sook;Yoon, Ji Hye
    • Journal of Photoscience
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    • v.11 no.1
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    • pp.35-40
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    • 2004
  • [Ru(2,2'-bipyridine)$_2$(4,4'-dicarboxy-2,2'-bipyridine)]$^{2+}$(RuBDc) is a very photostable probe that possesses favorable photophysical properties including long lifetime, high quantum yield, large Stokes' shift, and highly polarized emission. To evaluate the usefulness of this luminophore (RuBDc) for studying macromolecular dynamics, its intensity and anisotropy decays when conjugated to RNA bacteriophage MS2 were examined using frequency-domain fluorometry with a high-intensity, blue light-emitting diode (LED) as the modulated light source. The intensity decays were best fit by a sum of two exponentials, and the mean intensity decay time was 442.2 ns. The anisotropy decay data showed a single rotational correlation time (2334.9 ns), which is typical for a spherical molecule. The use of RuBDc enabled us to measure the rotational correlation time up to several microseconds. These results indicate that RuBDc can be useful for studying rotational diffusion of biological macromolecules.s.

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Propagating Spiral Waves Obtained in a Catalyst-Immobilized Gel Membrane by the Belousov-Zhabotinsky Reaction System

  • Kim, Bong-Seong;Jo, Eun-Ae;Basavaraja, C.;Huh, Do-Sung
    • Bulletin of the Korean Chemical Society
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    • v.31 no.7
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    • pp.1956-1962
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    • 2010
  • The formation of diverse spiral waves was studied in a polyacrylamide gel membrane with ruthenium(4-vinyl-4'-methyl-2,2'-bipyridine)bis(2,2'-bipyridine)bis(hexafluorophosphate) by a gas-free Belousov-Zhabotinisky (BZ) reaction system containing 1,4-cyclohexanedione (1,4-CHD). The gel membrane was found to be receptive for observing propagating waves since a clearer wave-train is obtained during a long reaction time without any disturbance from the immobilized metal catalyst which can be dissolved into the highly acidic solution of the BZ system. The distinctive waves in the system basically depend on both $BrO_3$ and 1,4-CHD in the initial phase, and are influenced by the intensity of illumination of visible light.

산소흡탈착능을 가지는 산소부화막의 개발

  • ;;荒木 孝二
    • Proceedings of the Membrane Society of Korea Conference
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    • 1997.10a
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    • pp.21-24
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    • 1997
  • 1.서론 : 산소선택성이 좋은 투과막은 산소부화에 의한 연소효율의 향상, 간이 산소발생장치에의 응용 등 여러가지의 용도가 예상된다. 이를 위한 준비단계로 막소재 및 막형상에 대한 검토가 \ulcorner발하게 진행되고 있다. 그 중에서 높은 산소선택성을 발현하는 방법이 주목되어지고 있는데 이는 가역적 산소흡탈착능을 갖는 carrier분자를 이용한 촉지운송계(facilitated transport system)를 구축하는 방법이 있다. 본 연구에서는 [Co(salen)]과 같은 $N_2O_2$형 평면정방착제(Square planar complex)이며, salen의 shift염기부분을 bipyridine cycle, phenoxide부분을 해리한 amide로 골격변환한 구조를 갖고 있는 6,6'-bis(benzoylamino)-2,2'-bipyridine(babpH$_2$)의 covalt착체([Co(babp)]를 배위결합에 의해 고분자막중에 고정하고, 산소흡탈착능, 산소투과성, 안정성 등을 검토하는 것을 바탕으로 우수한 선택성 산소투과막을 개발하는 것을 목적으로 한다.

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Synthesis and Crystal Structures of Di-nuclear Zinc(II) Diphenate Complexes with 1,10-Phenanthroline and 2,2'-Bipyridine

  • Koo, Bon-Kweon
    • Bulletin of the Korean Chemical Society
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    • v.32 no.8
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    • pp.2617-2622
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    • 2011
  • Two new Zn(II) complexes, $[Zn_2(dpa)_2(phen)_2(H_2O)_2]{\cdot}H_2O$ (1) (dpa = dephenate, phen = 1,10-phenanthroline) and [$Zn_2(dpa)_2(bpy)_2(H_2O)_2$] (2) (bpy = 2,2'-bipyridine) have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. The X-ray analysis reveals that the structures of 1 and 2 are dinuclear zinc(II) complexes bridged by dpa dianions, respectively. The zinc ions in 1 exhibit a distorted square pyramidal environments, while the zinc ions in 2 exhibit a trigonal bipyramid geometry. In each complex, the dpa ligand is coordinated to zinc ions as a bis-monodentate.

Synthesis and Characterization of properties for Iridium Complexes (Ir 착체의 합성과 특성에 관한 연구)

  • Kim, Dong-Hwan;Kim, Hwa-Seon;Kwak, Ji-Hoon;Lee, Ji-Hoon;An, Ho-Guen;Chung, Min-Chul
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.437-438
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    • 2007
  • A Iridium complexes has been synthesised from the reaction of [$lr(ppy)_2Cl_2$] with 5-bromo-2.2'-bipyridine, 5-Ethynyl-2.2'-bipyridine Characterization of the complexes were by FT-IR, $^1H(^{13}C)$-NMR and photo-, electro-chemistry properties were showed by UV-vis, Cyclicvoltammetry, Photoluminescence.

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Photoinduced Electron Tansfer of Microperoxidase-8

  • Su, Chien-Hua;Lin, Ren-Jay;Chang, I-Jy
    • Journal of Photoscience
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    • v.6 no.3
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    • pp.129-133
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    • 1999
  • Microperoxidase 8 (MP8) has been prepared by sequential hydrolysis of cytochrome C by pepsin and trypsin. This five-coordinated heme-octapetide fragment provides a uniques structure to evaluate the electronic coupling efficiency to the iron through axial position and porphyrin edge. At alkali pH, Ru(bpy)2(im)22+ is completely quenched in AcMP8Ru complex . Transient kinetics measurement showed the decay rate to be ~1 $\times$1012S-1. Ruthenium bipyridine complex with a carboxyl group substituted bipyridine has been prepared adn reacted with MR 8 to yield N-terminus bound RuMP8 complex. The luminescence decay rate has been measured as 1 $\times$109S-1. By using semiclassical electron transfer theory, we found the electron transfer efficiency through axial positioin of iron prophyrin is as good through prophyrin edge.

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A Study on CO Substitution of Group 6 Metal Carbonyls by Using Phase Transfer Catalyst(2) (상이동촉매에 의한 GROUP 6 금속카르보닐의 CO 치환에 관한 연구(2) : 반응시간과 촉매량에 의한 영향)

  • Yang, Hyun-Soo;Park, Ha-Seon
    • Applied Chemistry for Engineering
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    • v.3 no.3
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    • pp.407-411
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    • 1992
  • The effects of phase transfer catalyst was studied on the substitution of CO ligand of $Mo(CO)_6$ [M=Cr, Mo, W] with two electron-pairs donating ligands, 2, 2'-bipyridine and 2, 2'-biquinoline. The change of product yield, $M(CO)_4(L)_2$, was discussed according to reaction time, mole composition of $M(CO)_6$, and type of ligand.

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