• Korean Chemical Engineering Research
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• 제54권4호
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• pp.555-559
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• 2016

본 연구에서는 2,2'-bispyrimidine (bpim), 2,2'-bipyridine (bpy), 5,5'-dimethyl-2,2'-bipyridine (5,5-mebpy), 5'-bromo-2,2'-bipyridine (5-brbpy), 5,5'-dibromo-2,2'-bipyridine (5,5-brbpy), 4,4'-dimethyl-2,2'-bipyridine (4,4-mebpy), 4,4'-dihexyl-2,2'-Bipyridine (4,4-hebpy), 1,10'-Phenanthroline (phen), 3,4,7,8'-tetramethyl-1,10'-Phenanthroline (3,4,7,8-phen)을 사용하여 단핵 Platinum착체를 합성하였다. 합성되어진 Platinum착체의 화학적 구조를 결정하기 위해서 $^1H(^{13}C)$-NMR, FT-IR을 사용하였으며, 광 물리학적 특성에 대한 측정은 UV-vis, PL을 통하여 측정하였다. 합성한 Platinum착체는 356 nm~421 nm영역에서 발광파장이 확인되었으며, DMSO용액에서 내부양자효율이 0.05~0.46으로 나타났다.

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3891-3894
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• 2012

• 대한화학회지
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• 제41권8호
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• pp.385-391
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• 1997

Co$(dimethyl bipyridine)_3(ClO_4)_2$의 확산계수$(D_0)$와 전극반응속도상수$(K_0)$를 순환전압전류법과 대시간전류법으로 구하였다. 확산계수에 대한 용매, 농도, 주사속도 등의 영향과 반응속도상수에 대한 온도변화의 영향을 조사하였다. 25$^{\circ}C$에서 확산계수는 $5.54{\times}10^{-6 }cm^2/sec$이었고, 반응속도상수는 $2.39{\times}10^{-3 }/s$ 이었으며, 용매의 점도가 커질수록 봉우리전류값과 확산계수는 감소하였다. 반응속도상수에 대한 온도의 영향으로부터, ${\Delta}G^{\neq},\;{\Delta}H^{\neq},\;{\Delta}S$ 등의 열역학적 파라미터를 구하였다. 이 화합물은 $O_2$분자의 환원에서 봉우리전류를 크게 증가시키고, 환원전위를 양(+)전위방향으로 이동시키는 열역학적 전극촉매현상을 보였다.

• Bulletin of the Korean Chemical Society
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• 제14권6호
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• pp.682-686
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• 1993

The syntheses and reactivities with olefins of $[Ru^{II}(L_3)(L_2)OH_2]^{2+}$ $[L_3$= 2,6-bis(N-pyrazolyl)pyridine(bpp), 2,6-bis(3,5-dimethyl-N-pyrazolyl)pyridine $(Me_4bpp);\;L_2$= 2,2'-bipyridine(bpy), 4,4'-dimethyl-2,2'-bipyridine $(Me_2bpy)$] are described. Their spectral and redox properties in aqueous solution were investigated. Evidence for each one electron redox process for the $Ru^{IV}-Ru^{III}$ and $Ru^{III}-Ru^{II}$ couples has been obtained. Oxidation of $[Ru^{II}(bpp)(bpy)OH_2]^{2+}$ with $Ce^{IV}$ gave $[Ru^{IV}(bpp)(bpy)O]^{2+}$. The $[Ru^{IV}$= 0 complex is paramagnetic $({\mu}_{eff}=2.82)$ and the complexes $[Ru(L_3)(L_2)OH_2]^{2+}$ are robust catalysts for the oxidation of styrene, cyclohexene, and cyclooctene with cooxidant such as NaOCl. Product distributions and selectivities are discussed by varying the number of the substituted-methyl group in the ring.

• Bulletin of the Korean Chemical Society
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• 제12권6호
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• pp.686-691
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• 1991

Emission quenching of photoexcited tris(${\alpha},{\alpha} '$-diimine)-ruthenium(II) complex cations, $RuL_3^{2+}$ (L: 2,2'-bipyridine, 4,4'-dimethyl-2,2'-bipyridine; 4,4'-diphenyl-2,2'-bipyridine; 1,10-phenanthroline; 5-methyl-1,10-phenanthroline; 5,6-dimethyl-1,10-phenanthroline or 4,7-diphenyl-1,10-phenanthroline) by $Cu^{2+}$, dimethylviologen $(MV^{2+})$, nitrobenzene (NB), and oxygen was studied in aqueous homogeneous and sodium dodecyl sulfate (SDS) micellar solutions. The apparent bimolecular quenching rate constants $k_q$ were determined from the quenching data and life-times of $^{\ast}RuL_3^{2+}$. In homogeneous media, the quenching rate was considerably slower than that for the diffusion-controlled reaction. The decreasing order of quenching activity of quenchers was $NB>O_2>MV^{2+}>Cu^{2+}$. The rate with $Cu^{2+}$ was faster as the reducing power of $^{\ast}RuL_3^{2+}$ is greater. On the other hand, the rates with NB and $O_2$ were faster as the ligand is more hydrophobic. This was attributed to the stabilization of encounter pair by van der Waals force. The presence of SDS enhanced the rate of quenching reactions with $Cu^{2+}$ and $MV^{2+}$, whereas it attenuated the quenching activity of NB and $O_2$ toward $RuL_3^{2+}$. The binding affinity of quenchers to SDS micelle and binding sites of the quenchers and $RuL_3^{2+}$ in micelle appear to be important factors controlling the micellar effect on the quenching reactions.

• Bulletin of the Korean Chemical Society
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• 제11권6호
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• pp.552-557
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• 1990

Luminescence quenching reactions of photoexcited tris(2,2'-bipyridine)ruthenium (Ⅱ) complex cation, $Ru(bpy)_3\;^{2+}$, by dialkylviologens (dimethyl, dioctyl, dibenzyl, methyloctyl, methyldodecyl, and methylbenzyl) were studied in sodium dodecylsulfate (SDS), poly(styrenesulfonate) (PSS), and poly(vinylsulfonate) (PVS) solutions. The relative quenching rate varies widely with the microheterogeneous media employed: the highest quenching rate is observed for methyldodecylviologen in homogeneous aqueous medium, dibenzylviologen in SDS and PVS solutions, and dimethylviologen in PSS solution; the lowest rate is found for dimethylviologen in homogeneous medium and SDS solution, methyldodecylviologen in PSS and PVS solutions. These results were interpreted in terms of reduction potential of viologens, affinity of $Ru(bpy)_3\;^{2+}$ and viologens to the microparticles, and the structures of the viologen-colloid complexes.

• 전기화학회지
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• 제19권2호
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• pp.29-38
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• 2016

전기화학적 방법을 통한 요산 (Uric acid) 정량분석을 위해 수용성 고분자 (hydrogel polymer)를 배위시킨 오스뮴 고분자 화합물과 요산 산화효소 (Uricase), 가교를 위한 PEGDGE (poly(ethylene glycol) diglycidyl ether)가 혼합된 용액을 스크린 프린팅된 탄소 전극 (SPCEs) 위에 흡착하여 측정하였다. 수용성 오스뮴 고분자의 전위를 조절하기 위해 리간드인 피리딘링의 4번 위치에 다른 전기음성도의 작용기를 갖는 오스뮴 고분자 화합물을 합성하였다. 합성된 오스뮴 고분자 화합물은 PAA-PVI (Poly(acrylic acid)-poly(vinyl imidazole)-$[osmium(4,4^{\prime}-dichloro-2,2^{\prime}-bipyridine)_2Cl]^{+/2+}$), PAA-PVI-$[osmium(4,4^{\prime}-dimethyl-2,2^{\prime}-bipyridine)_2Cl]^{+/2+}$, PAA-PVI-$[osmium(4,4^{\prime}-dimethoxy-2,2^{\prime}-bipyridine)_2Cl]^{+/2+}$이다. 제작된 효소전극은 순환전압전류법 (cyclic voltammetry)을 통해 uric acid에 의한 오스뮴 고분자 화합물들의 산화 촉매 전류(oxidation catalytic current)를 측정하여 uric acid의 농도를 정량적으로 분석할 수 있었다. 오스뮴 고분자 화합물들 중 0.215 V의 산화환원 전위를 갖는 $PAA-PVI-[Os(dme-bpy)_2Cl]^{+/2+}$ (PAA-PVI-osmium$(4,4^{\prime}-dimethyl-2,2^{\prime}-bipyridine)_2Cl$]$^{+/2+}$) 화합물을 이용하여 대표적인 간섭물질인 아스코르브산 (AA)과 포도당 (glucose)의 산화 신호의 간섭효과를 피할 수 있었다. 이를 이용하여 제작된 전극은 0.33 V 전위에서 다양한 농도의 uric acid (1.0, 1.5, 2.0, and 5.0 mM)의 전류를 측정한 결과 $r^2=0.9986$의 좋은 선형성을 갖는 것을 확인하였다. 이는 복잡하지 않은 간단한 방법과 일회용의 전극을 사용하기 때문에 현장현시 검사 (point of care; POC)에 적합한 요산측정용 바이오센서로서의 가능성을 확인 할 수 있었다.