• Title/Summary/Keyword: ion complex

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Complex of zinc(II) with tetraaza macrocyclic ligands in solution (용액에서 Zn(II)이온과 tetraaza 거대고리 리간드의 착물)

  • Koh Kwang-Oh
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.4
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    • pp.733-737
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    • 2006
  • In this paper, we report the coordination state and structure of $Zn(cyclam)Cl_{2})$ complex that was studied by the Raman spectrum and conductivity method. The complex of zinc(II) ion with 1,4,8,11-tetraazacyclotetradecane(cyclam) ligand is formed in aqueous solution. According to the Raman spectrum of $Zn(cyclam)Cl_{2})$ complex, $H_{2}O$ molecule and $Cl^{-}$ ion compete for the trans coordination site of zinc(II) ion. We also have investigated the competition effect of $H_{2}O$ molecule and $Cl^{-}$ ion by the conductivity method. On addition of 1,4,8,11-tetraazacyclotetradecane(cyclam) ligand to the aqueous $ZnCl_{2}$ solution, 2: 1 electrolyte is changed to 1:1 electrolyte. We suggest the possibility of elimination of heavy metal because of the affinity effect of macrocyclic polyamine(1,4,8.11-tetraazacyclotetradecane) for the heavy metal,.

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Selective Synthesis of a New Macropolycycle Containing One N-CH2-N Linkage and Its Reaction with Cu2+ and Ni2+ Ions in Methanol

  • Kang, Shin-Geol;Kweon, Jae-Keun;Jeong, Gyeong-Rok;Lee, Uk
    • Bulletin of the Korean Chemical Society
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    • v.29 no.10
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    • pp.1905-1910
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    • 2008
  • The reaction of 3,14-dimethyl-2,6,13,17-tetraazatetracyclo[16.4.0$0^{1.18}.0^{7.12}$]docosane ($L^1$) with formaldehyde in warm methanol yielded 3,14-dimethyl-2,6,13,17-tetraazatetracyclo[16.4.$1^{2.6}.0^{1.18}.0^{7.12}$]tricosane ($L^7$) containing one 1,3-diazacyclohexane subunit. In methanol, $L^7$ readily reacts with $Cu^{2+}$ ion to form [$CuL^7(H_2O)$]$^{2+}$ which is extremely inert against methanolysis. In the solution containing $Ni^{2+}$ ion, however, $L^7$ reacts with methanol to yield [$NiL^3$]$^{2+}$ ($L^3$ = 2-(methoxymethyl)-5,16-dimethyl-2,6,13,17-tetraazatricyclo[16.4.$0^{1.18}.0^{7.12}$]- docosane), in which one N-$CH_2OCH_3$ pendant arm is appended. The copper(II) complex [$CuL^7(H_2O)$]- $(ClO_4)_2{\cdot}3H_2O\;(I{\cdot}3H_2O)$ has a severely distorted trigonal bipyramidal coordination geometry with a 4-5- 6-5 chelate ring sequence. The crystal structure of [$NiL^3$]$(PF_6)_2{\cdot}2H_2O$ (IIb) shows that the N-$CH_2OCH_3$ pendant arm is not coordinated to the metal ion in the solid state. In various solvents (S), however, the nickel(II) complex exists as a mixture of [$NiL^3$(S)]$^{2+}$, in which the N-$CH_2OCH_3$ group as well as S is coordinated to the metal ion, and [$NiL^3$]^{2+}.

Complex Formation between 3CaO.$Al_2O_3$ and Sodium Gluconate (3CaO.$Al_2O_3$와 글루콘산 나트륨간의 착체형성)

  • 김창은;이승헌;이승규
    • Journal of the Korean Ceramic Society
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    • v.27 no.7
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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.

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Stability and Environmental Safety of a Nanosized Agroformulation by Using Gamma-irradiation Technique (감마선을 이용하여 제조한 농업용 나노제제의 보존성 및 환경안전성)

  • Park, Hae-Jun;Kim, Hwa-Jung;Choi, Jin-Su
    • Journal of Radiation Industry
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    • v.7 no.2_3
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    • pp.171-176
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    • 2013
  • In previous study, the novel nanosized curdlan-silica complex for a sustain-releasing effect was developed by using gamma-irradiation. It can be applicable to use in various sustainr-eleasing formulation in agriculture industry. This study was conducted to investigate its storage stability and environmental toxicity in an accelerated condition. The complex samples were treated with high temperature condition ($65^{\circ}C$) during 3 weeks, and then sustain-releasing property of complex was verified thereby using Ion Chromatography on a weekly basis. The morphology of the complex was characterized using scanning electron microscopy (SEM). Results of Ion Chromatography analysis showed that sample treated for 3 weeks was similar to sustain-releasing pattern of non-treatment sample. We verify concluded that the complex is able to keep its sustain-releasing property and sustained-releasing in 3 years. Also the formulation has no environmental toxicity.

Drug Release Characteristics of Famotidine-Cationic Exchange Resin Complexes and Their Pharmacokinetics in Rats (파모티딘-양이온 교환수지 복합체의 약물방출 특성 및 흰쥐에서의 체내동태)

  • Shin, Dong-Sun;Song, Woo-Heon;Choi, Young-Wook
    • Journal of Pharmaceutical Investigation
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    • v.27 no.4
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    • pp.313-321
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    • 1997
  • Ion exchange resin complexes of famotidine have been prepared by the reaction of famotidine solution with activated ion exchange resins. Complex formation efficiency between famotidine and ion exchange resin was about $80{\sim}90%$ in average, calculated by HPLC determination. Drug release characteristics from the resin complexes were evaluated by the modified percolation method. Famotidine release was dependent on the type of ion exchange resins. In the case of weakly acidic resin complexes, the cumulative released amount of famotidine was more than 90% for 1hr in pH 1.2 buffer solution. However, in the case of strongly acidic resin complexes, it was less than 5% for 3hr in the same medium. Strongly acidic resins revealed some advantages over weakly, acidic resins for overcoming instability of famotidine in gastric juice. In addition, strongly acidic resin complexes showed controlled release of famotidine in pH 6.8 buffer solution, showing the result of about 60 to 70% of drug release for 5hr. After oral administrations of famotidine-resin complexes to rats as dose of 40 mg equivalent/kg, the pharmacokinetic parameters of famotidine were obtained by model independent analysis and compared with those of famotidine solution or suspension. $C_{max}$ of famotidine-resin complex was lower than that of famotidine solution or suspension. MRT, MAT, and MDT of the complexes were greater than those of famotidine solution or suspension. From these results, it was expected that famotidine was released slowly from the complexes and absorbed continuously into systemic circulation. It was recognized that drug release from the complexes was the rate-limiting step in drug absorption, since there were close correlations between in vitro drug release and in vivo pharmacokinetic parameters.

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Adsorption Characteristics by Synthesized Goethite in the Mixed Solution Systems of Phosphate, Sulfate, and Copper Ions (합성 Goethite에 의한 인산이온, 황산이온 및 구리이온의 혼합용액에서의 흡착특성)

  • 감상규;이동환;이민규
    • Journal of Environmental Science International
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    • v.12 no.10
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    • pp.1055-1060
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    • 2003
  • Adsorption on goethite of individual component from a solution containing phosphate, sulfate, or copper ion was investigated. Competitive adsorption in the binary and ternary solution systems composed of phosphate, sulfate, and copper ions was also investigated. In competitive adsorption systems with phosphate and sulfate ions, the presence of phosphate ion reduced the adsorption of sulfate ion largely. On the other hand, the presence of sulfate ion caused only a small decrease in phosphate adsorption. This result suggests that phosphate ion is a stronger competitor for adsorption on goethite than sulfate ion, which is consistent with the higher affinity of phosphate for the surface compared to sulfate ion. Compared to the results from single-sorbate systems, adsorption of copper ion in the binary system of sulfate ion and copper ion was found to be enhanced in the presence of sulfate ion. Addition of sulfate ion to the binary system of copper ion and phosphate ion resulted in a small enhancement in copper sorption. This result implies that the presence of sulfate ion promotes adsorption of the ternary complex FeOHCuSO$_4$. The adsorption isotherms could be well described by the Langmuir adsorption equation.

Current characteristics of Cu/NaCl electrolyte/Zn electrochemical cell (구리/NaCl 전해질/아연 전기화학전지의 전류특성)

  • Kim, Yong-Hyuk
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.9
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    • pp.1626-1631
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    • 2010
  • The characteristics of electric current for the voltaic cell are important for electric power applications. In this paper, an electrical equivalent model consist of three resisters and a capacitance for the Cu/NaCl solution/Zn electrochemical cell is proposed. The capacitance which exists in the Zn electrode/electrolytic interface increased according to Zn electrode area, but cannot affect almost in electric current. Complex impedance plot was used to analysis the interface effect for Zn/electrolyte. This result shows that the interface is similar with the electric transmission line. The short current measurements were conducted to investigate the effects of hydrogen peroxide, the watery sulfuric acid and NaCl aqueous solution. As the hydrogen peroxide increased, the electric current increased because the hydrogen gas being converted with the water. Also electric current increased significantly with increase of the hydrogen ion with the watery sulfuric acid and increased with increase of $Na^+$ ion and $Cl^-$ion in the NaCl electrolyte.

In Vitro Controlled Release of Piracetam with Coated Ion-Exchange Resin (이온교환수지를 이용한 피라세탐의 in vitro 방출조절)

  • Hwang, Young-Sook;Lee, Kyung-Tae;Seo, Seong-Hoon
    • Journal of Pharmaceutical Investigation
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    • v.29 no.2
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    • pp.105-109
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    • 1999
  • The sustained release of piracetam by complexation with ion exchange resin was prepared. The complex was coated with Eudragit RS100 and their releases in vitro were conducted with various different kinds of medium solution. Dissolution rate increased as ionic strength, acidity and drug concentrations increased and reached its maximal plateau concentration within 5 min. Based on these data, The controlled release of piracetam using ion-exchange piracetam complex coated with Eudragit RS100 could be available.

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A Study on Complex Formation of Cd (II) Ion with Hydrazide Schiff (Hydrazide Schiff Base 리간드와 Cd(II) 이온과의 착물 형성에 관한 연구)

  • Kyu-Seong Choi;Yong-Kyu Kim;Yong-Nam Kim
    • Journal of the Korean Chemical Society
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    • v.35 no.2
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    • pp.142-150
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    • 1991
  • The complexation of hydrazide schiff base ligands such as N,N'-oxalylbis(salicylaldehyde hydrazone), N,N'-malonylbis(salicylaldehyde hydrazone), and N,N'-succinylbis(salicylaldehyde hydrazone) with Cd(II) ion was studied by polarographic method in DMSO solution. The order of stability constants was OBSH < MBSH < SBSH, and these ligands formed stable complexes with Cd(II) ion. The stability constants of complexation were measured at various temperatures. As the results, ${\Delta}$H and ${\Delta}$S of the complexation were distributed on the complex stabilities.

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Determination of Acidic Drug with ISEs Using Ternary Complex of Metal-di-2-pyridyl Ketone Oxime-acidic Drug as Ion-Exchanger (이온교환체로서 금속-디-2-피리딜케톤옥심-산성의약품 3원 착물을 이용한 산성의약품의 정량)

  • 안문규;오원정;이언경;이순영;이재윤;정문모;허문회
    • YAKHAK HOEJI
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    • v.46 no.5
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    • pp.320-323
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    • 2002
  • A method for the determination of acidic drug, mefenamic acid and ibuprofen with ion-selective electrode(ISE) using Fe(II)-di-2-pyridyl ketone oxime complex as a counter ion were developed. Benzyl-2-nitrophenyl ether(BNPE) plasticized membrane was more selective and sensitive than the other tested membranes. The acidic drug selective electrode exhibits a linear response for 10$^{-2}$ M 510$^{-5}$ M of acidic drugs, mefenamic acid and ibuprofen with a slope of -55.9 and -56.3 mV/dec. in borate buffer solution (pH 8.9). Potentiometric selectivity measurements revealed negligible interferences from aromatic and aliphatic carboxylic acid salts. The electrodes were found to be useful for the direct determination of mefenamic acid and ibuprofen in pharmaceutical preparations.