• 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.

• 대한기계학회논문집B
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• 제36권5호
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• pp.533-538
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• 2012

본 논문에서는 산소 민감 발광 염료를 이용하여 마이크로 채널 내에서 세포가 배양되고 있을 때 산소농도를 측정하였다. 현재까지 알려진 여러 산소 민감 발광 염료 중 본 논문에서는 물에 잘 녹으며 장 시간 동안 사용하여도 독성이 없는 것으로 알려진 $[Ru(bpy)_3]^{2+}$를 사용하였으며 이와 더불어 산소 민감 염료 측정법의 단점을 보완하기 위하여 칼세인 염료를 이용하여 두 염료의 밝기 비율을 구하여 농도를 측정하였다. SCOMS 카메라와 마이크로 채널을 이용하여 캘리브레이션을 실시하고 농도와 밝기와의 관계를 구하였으며 이 관계를 이용하여 세포가 배양되는 조건에서의 배양액의 산소농도를 측정하였다. 실험 결과 채널입구에서 점점 멀어질수록 마이크로 채널 내에서 산소농도는 점점 낮아진다는 것을 관찰 할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2253-2259
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• 2011

The self-assembly of one novel organic complex based on chlorogenic acid (HCA) and 2,2'-bipyridine (2,2'-bipy) has been synthesized and characterized. The complex achieved by hydrogen-bonding interactions, adopted a 1:1 stoichiometry in a solid state. The proton transfer occurred from the carboxyl oxygen to the aromatic nitrogen atom to form salts CA${\cdot}$(2,2'-Hbipy), the 2,2'-Hbipy molecule individually occupies the pseudo-tetragonum that is formed with CA. In this paper, the interactions of CA${\cdot}$(2,2'-Hbipy) with bovine serum albumin (BSA) were studied by fluorescence spectrometry. For CA${\cdot}$(2,2'-Hbipy), HCA and 2,2'-bipy, the average quenching constants for BSA were $2.4384{\times}10^4$, $4.653{\times}10^3$, and $3.059{\times}10^3\;L{\cdot}mol^{-1}$, respectively. The mechanism for protein fluorescence quenching is apparently governed by a static quenching process. The Stern-Volmer quenching constants and corresponding thermodynamic parameters ${\Delta}$H, ${\Delta}$G and ${\Delta}$S were calculated. The binding constants and the number of binding sites were also investigated. The conformational changes of BSA were observed from synchronous fluorescence spectra.

• 공업화학
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• 제27권5호
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• pp.512-515
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• 2016

새로운 viologen 유도체인 1,1'-bis(3,4-dihydroxybutyl)-[4,4'-bipyridine]-1,1'-diium bromide (V-Pr-2OH)을 합성하여 PTB7 : $PC_{71}BM$ Blend를 기반으로 하는 inverted polymer solar cells (iPSCs)에 cathode buffer layer로 적용하였다. V-Pr-2OH이 cathode buffer layer로 적용된 PSCs (ITO/V-Pr-2OH/PTB7 : $PC_{71}BM/MoO_3/Ag$)의 power conversion efficiency (PCE)는 7.28%이었다. V-Pr-2OH이 없는 iPSCs (ITO/ZnO/PTB7 : $PC_{71}BM/MoO_3/Ag$)의 PCE (7.41%)에 상응하는 값이다. 그러므로 본 연구에서는 높은 열처리 공정이 필요한 ZnO가 배제된, 즉 높은 온도의 열처리 없이도 제작 가능한 PSC에 대한 가능성을 보여주고 있다.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2329-2337
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• 2009

Three heteroleptic ruthenium sensitizers, Ru(L)($L^1)(NCS)_2$ [L = 4,4'-dicarboxylic acid-2,2'-bipyridine, Ru-T1: $L^1$ = (E)-2-(4'-methyl-2,2'-bipyridin-4-yl)-3-(thiophen-2-yl)acrylonitrile, Ru-T2: $L^2$ = (E)-3-(5'-hexyl-2,2'-bithiophen-5- yl)-2-(4'-methyl-2,2'-bipyridin-4-yl)acrylonitrile, and Ru-T3: $L^3$ = (E)-3-(5"-hexyl-2,2':5',2"-terthiophen-5-yl)-2- (4'-methyl-2,2'-bipyridin-4-yl)acrylonitrile)], were synthesized and used as photosensitizers in nanocrystalline dyesensitized solar cells (DSSCs). The introduction of the 3-(5-hexyloligothiophen-5-yl)acrylonitrile group increased the conjugation length of the bipyridine donor ligand and thus improved their molar absorption coefficient and light harvesting efficiency. DSSCs with the configuration of Sn$O_2$: F/Ti$O_2$/ruthenium dye/liquid electrolyte/Pt devices were fabricated using these Ru-$T1{\sim}T3$ as a photosensitizers. Among the devices, the DSSCs composed of Ru-T2 exhibited highest power conversion efficiency (PCE) of 2.84% under AM 1.5 G illumination (100 mW/$cm^2$).

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.3003-3008
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• 2011

Reactions of benzyl alcohol and its derivatives by [Ru$^{IV}$(tpy)(dcbpy)(O)]$^{2+}$ (tpy = 2,2':6',2"-terpyridine; dcbpy = 4,4'-dicarboxy-2,2'-bipyridine) leading to the corresponding benzaldehydes in acetonitrile and water have been studied. Kinetic studies show that the reaction is first-order in both alcohol and oxidant, with k = 1.65 (${\pm}$ 0.1) $M^{-1}s^{-1}$ at $20^{\circ}C$, ${\Delta}H^{\ddag}$ = 4.3 (${\pm}$ 0.1) kcal/mol, ${\Delta}S^{\ddag}$ = -22 (${\pm}$ 1) eu, and $E_a$ = 4.9 (${\pm}$ 0.1) kcal/mol. High ${\alpha}$ C-H kinetic isotope effects are observed, but O-H solvent isotope effects are negligible. Spectral evidences with the isotope effects suggest that oxidation of benzyl alcohols occurs by a two-electron, hydride transfer. The catalytic cycles of aerobic benzyl alcohol oxidation are employed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.240-243
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• 1995

The basic electrochemical and photochemical behavior of ultrathin mono- and hetero-type LB film of amphiphilic Ru bipyridine complex adsorbed on ITO electrode by the Langmuir- Blodgett(LB) method as monolayer and alternating multilayer state. With theoretical equation of cyclic voltammetry for redox species, the cyclic voltammogram were simulated successfully taking account the interaction parameters. We could fit almost all measured voltammograms with k$^{\circ}$=72s$\^$-1/, ${\alpha}$$\sub$a/=0.44, ${\alpha}$$\sub$c/=0.54, $\Gamma$$\sub$T/=1.4${\times}$10$\^$-10/, k=0.015s$\^$-1/ values. The AFM images of mono and hetero type LB film surfaces on ITO were also studied.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.585-588
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• 2005

Bipyridine and its derivatives have been widely used as the ligands in transition metal complexes. The proton affinities of pyridine derivatives were calculated using an ab initio quantum mechanical method (B3LYP with various double zeta and triple zeta basis sets) in combination with the Poisson-Boltzmann continuum solvation model. Van der Waals radii of the atoms in the heterocyclic rings for the solvation energy calculation were set to values determined to reproduce the $pK_a$ values of guanine and oxoguanine derivatives and that of chlorine was optimized to reproduce the experimental values of relating compounds. The $pK_a$ values for the heterocyclic ring compounds were in agreement with the experimental values with a mean unsigned error of 0.45 $pK_a$ units.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.152-152
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• 2010

본 연구에서는 인광 효과가 큰 heavy metal 인 이핵 Iridium 착체가 합성된 구조적, 광학적 및 전기적 특성을 배경으로 하였다. 가교제로는 카본 conjugated 된 리간드 bipyridine계 배위자를 사용하여 단핵 및 이핵 Platinum 착물 화합물을 합성 하였다. 합성 되어진 이핵 Platinum 착물 화합물의 화학적 구조를 결정하기 위해 $^1H(^{13}C)$-NMR, UV-vis, Spectro Photometer, MALDI TOF-MS 등을 사용하였으며, 광 물리적, 전기화학적 측정을 Spectrofluoromete, Cyclic Voltammetry를 통해 관찰 하였다.

• Bulletin of the Korean Chemical Society
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• 제24권10호
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• pp.1490-1494
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• 2003

Noncovalently linked electron donor-acceptor dyad consisting of zinc tetratolylporphyrin and pyridine appended ruthenium trisbipyridine comlex was prepared, via axial coordination of pyridine moiety in ruthenium trisbipyridine complex on zinc tetratolylporphyrin. For the purpose of comparison, axial coordination of pyridine-appended 2,2'-bipyridine on zinc tetratolylporphyrin was also investigated. The Kvalues were detemined based on absorption of fluorescence studies. The fluorescence of zinc teratolylporphrin was efficiently quenched upon axial coordination of pyridine moiety, prbably due to the photoinduced electron transfer from zinc tetrtolylporphyrin to ruthenium trisbipyridine, supported by free enegy estimation.