• 대한화학회지
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• 제11권4호
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• pp.121-125
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• 1967

各種 아민과 할로겐化合物間의 Charge Transfer Complex 形成與否를 檢討하여 보았다. Pyridine Tridthylamine, Piperidine Ethanolamine Triethanolamine, Aniline, Diethylamine 等의 아민類와 四鹽化炭素 또는 클로로폼의 混合溶液을 n-Hexane 溶媒存在下에서 紫外線吸收 스펙트라를 檢査한 結果 장파장쪽의 Shift가 있었으며 特히 Diethylamine과 Triethylamine은 클로로폼 또는 四鹽化炭素와 1:1 Charge Transfer Complex를 形成하였고, Piperidine은 接觸的 Complex를 形成하는 것이 確認되었다. Complex의 形成경향과 아민의 Nucleophilicity와의 關係를 論議하였다.

• KSBB Journal
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• 제10권2호
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• pp.149-158
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• 1995

각종 CD와 여러 종류의 화합물, pH indicator, biostain, 아미노산, 천연배당체, 그리고 fatty acid 간의 inclusion complex 형성능을 비교하였다. Fatty acid가 각종 CD에 대한 포접형성능과 선택성 이 높아 CD 분리용 ligand로 적합함을 알았다. Fatty acid의 포접능과 선택성은 탄소쇄의 길이와 밀접한 상관관계를 나타내어 capric acid는 ${\alpha}$- CD와 palmitic acid는 ${\beta}$-CD와 높은 선택성을 보였다. Complex형성에 미치는 반융조건인 흔합 농도비, pH, ionic strength, 그리고 온도의 영향을 검토하였다. 적정 혼합 농도비는 CD가 50mM 그리고 lig and 인 fatty acid가 50mM 일 때 였으며 , 온도가 중 요한 형성조건으로 작용하였다. 포접되지 않은 CD 와 fatty acid가 포접 된 CD의 분자구조를 X-ray diffraction과 IR spectrum을 사용하여 비교 검토하였으며, DSC로 inclusion complex 형성반응의 en­t thalpy의 변화값(${\gamma}H$)을 측정하여 발열반응임을 확인하였다.

• 약학회지
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• 제7권1호
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• pp.1-7
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• 1963

This investigation is the studies on the solubility analysis for several pharmaceuticals. The equilibrium reactions leading to complex formation of Caffeine and Nicotinamide with Lidocaine and Saccharin have been studied. The equilibrium constant of each complexes have also been calculated. It is shown that complex formation may lead to an increase in the solubilities of the reactants, and that Nicotinamide has more complexing activity than Caffeine. The influence of chemical structure of each components on interaction is also discussed.

• BMB Reports
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• 제52권10호
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• pp.607-612
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• 2019

During meiosis, programmed double-strand breaks (DSBs) are repaired via recombination pathways that are required for faithful chromosomal segregation and genetic diversity. In meiotic progression, the non-homologous end joining (NHEJ) pathway is suppressed and instead meiotic recombination initiated by nucleolytic resection of DSB ends is the major pathway employed. This requires diverse recombinase proteins and regulatory factors involved in the formation of crossovers (COs) and non-crossovers (NCOs). In mitosis, spontaneous DSBs occurring at the G1 phase are predominantly repaired via NHEJ, mediating the joining of DNA ends. The Ku complex binds to these DSB ends, inhibiting additional DSB resection and mediating end joining with Dnl4, Lif1, and Nej1, which join the Ku complex and DSB ends. Here, we report the role of the Ku complex in DSB repair using a physical analysis of recombination in Saccharomyces cerevisiae during meiosis. We found that the Ku complex is not essential for meiotic progression, DSB formation, joint molecule formation, or CO/NCO formation during normal meiosis. Surprisingly, in the absence of the Ku complex and functional Mre11-Rad50-Xrs2 (MRX) complex, a large portion of meiotic DSBs was repaired via the recombination pathway to form COs and NCOs. Our data suggested that Ku complex prevents meiotic recombination in the elimination of MRX activity.

• 한국막학회:학술대회논문집
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• 한국막학회 1994년도 춘계 총회 및 학술발표회
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• pp.61-62
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• 1994

In order to prepare polyion complex membranes useful for the separation of water-alcohol by pervaporation, k-carrageenan containing artionic sulfate groups in the backbone and good hydrophilicity was selected for the polyanion membrane material and poly{1,3-bis[4-butyl pyridinium] propane. bromide}, one of the polycations synthesized in our lab and containing cationic pyridinium groups., was used. The polyion complex membranes were prepared by the ion complex formation between kcarrageenan films and poly{1,3-bis[4-butyl pyridinium] propane. bromide}. On the formation process of polyion complex membranes, the way of potyion complex formation was carefully studied. In order to study the effect of the morphology on the permeation properties of the polyion complex membranes, which is one of the important factors affecting on the permeation properties of membranes but rarely studied, the microstructure behaviors of the polyion complex mem6ranes in methanol-water mixtures with different compositions Were also studied with x-ray diffractometry and polarizing microscopy.

• 한국세라믹학회지
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• 제27권7호
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• pp.883-890
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• 1990

Although various theories have been presented on the mechanism of setting retardation of 3CaO·Al2O3, this phenomenon has not yet been defined. The present investigation was initiated in order to solve the mechanism from the view point of coordination chemistry. The solubility of Ca(OH)2 in aquous solution of soldium gluconate was abnormally high, and was proportional to the concentration of sodium gluconate. These phenomena were attributed to the soluble complex formation, that is, (1 : 1)Ca complex formation between calcium ion and gluconate ion. The author's proposal was further confirmed by the results of electrical conductivity measurement. The formation of calcium complex was also supported by IR spectra and DTA. When sodium gluconate was dissolved in 3CaO·Al2O3 suspension, calcium complex and aluminum complex were formed. As an experimental evidence, the asymmetric stretching vibration of carboxyl group in sodium gluconate was observed to be shifted to lower frequency from 1625cm-1 to 1585cm-1 characteristically. The characteristic exothermic peaks of the complexs at 430℃ and 700℃ observed in DTA curve also suggest the formation of the complexs between sodium gluconate and 3CaO·Al2O3.

• Food Science and Biotechnology
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• 제18권3호
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• pp.782-787
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• 2009

In prion disease, spongiform neurodegeneration is preceded by earlier synaptic dysfunction. There is evidence that soluble N-ethylmaleimide sensitive factor attachment receptor (SNARE) complex formation is reduced in scrapie-infected in vivo models, which might explain this synaptic dysfunction because SNARE complex plays a crucial role in neuroexocytosis. In the present study, however, it is shown that prion protein (PrP) does not interfere with SNARE complex formation of 3 SNARE proteins: syntaxin 1a, SNAP-25, and synaptobrevin. Sodium dodecyl sulfate-resistant complex formation, SNAREdriven membrane fusion, and neuroexocytosis of PC12 cells were not altered by PrP. Thus, PrP does not alter synaptic function by directly interfering with SNARE complex formation.

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.795-798
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• 2008

The formation of complex $XeHCl^+$ in the collision-induced reaction of $Xe^+$ with HCl has been studied by use of classical dynamics procedures using the London-Eyring-Polanyi-Sato empirical potential energy surfaces. A small fraction of trajectories on the $Xe^+$ + HCl and Xe + $HCl^+$ surfaces lead to the formation of complex $XeHCl^+$ with life-times of 1-2 ps which is long enough to survive many rotations before redissociating back to the reactant state. The formation of complex $XeHCl^+$ occurs mainly from collision angle of $\Theta$ = ${45^{\circ}}$.

• Bulletin of the Korean Chemical Society
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• 제5권3호
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• pp.121-126
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• 1984

The charge transfer complex formations between indole derivatives and methylviologen were investigated spectroscopically. In aqueous solutions near room temperature, the order of complex stability was tryptamine < tryptophan < indole < indole acetate, which is the reverse order of the magnitude of molar absorptivities. This was interpreted as involvement of contact charge transfer. The decrease of enthalpy of complex formation (-${\Delta}$H) was highest in tryptamine, and lowest in indole acetate. ${\Delta}$H and entropy of complex formation (${Delta}$S) varied nearly in a linear fashion with isokinetic temperature $242^{\circ}$K. These results were attributed to the hydration-dehydration properties of the side chains in indole derivatives. Except indole acetate, the complex formations were greatly enhanced by the addition of sodium dodecyl sulfate(SDS). However, the direct relationship between the enhanced complex formation and SDS micelle formation was not found. The enhanced charge transfer interaction inSDS solutions was attributed to the increased ${\Delta}$S by interaction between methylviologen and SDS in premicellar level. The order of complex stability in SDS solutions was indole acetate < tryptophan < trypamine < indole, which reflects the hydrophobicity of indole derivatives as well as electrostatic interaction between indole derivatives and methylviologen associated with SDS.

• Journal of Photoscience
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• 제3권3호
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• pp.153-158
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• 1996

The effects of $\alpha$- and $\beta$-cyclodextrins (CD) on the twisted intramolecular charge transfer (TICT) behavior of p-N,N'-dimethylaminobenzoic acid (DMABA) in buffered aqueous solution have been investigated by examining formation and decay behaviors of the TICT-typical dual fluorescence. The ratio of the TICT emission to the normal emission (I$_a$/I$_b$) increases linearly $\alpha$-CD concentration increases, while in the presence of $\beta$-CD it shows nonlinear dependences on the CD concentration. The analysis of the CD-dependent changes of the I$_a$/I$_b$ and absorption spectra demonstrates formation of 1:1 inclusion complexes between DMABA and CDs. The decay time of the normal emission (ca. 700 ps) is little affected by the formation of $\alpha$-CD inclusion complex, whereas it increases upto ca. 1.6 ns upon formation of $\beta$-CD inclusion complex. The TICT emission for the $\beta$-CD inclusion complex exhibits two decay components while it shows a single component for the $\alpha$-CD inclusion complex, indicating formation of one or two types of inclusion complex in the presence of $\alpha$-CD or $\beta$-CD, respectively. These results are attributed to the CD cavity size dependence on patterns of complexation between CDs and DMABA. The CD size dependences of the TICT fluorescence properties with the orientation of the guest molecule demonstrate that the specific hydrogen bonding between the carboxylic acid group and water plays an important role in the excited-state TICT.