• Textile Coloration and Finishing
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• v.12 no.4
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• pp.264-268
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• 2000

Molecular-based materials with such functions as catalysis, magnetism and coordinate clathrations of one-, two-, and three-dimensional infinite frameworks have been extensively studied. Although rigid bridged ligands were frequently employed to construct these materials, flexible ligands were exploited less for this purpose. A one-dimensional polymer ${[Cd_2(=mu-bpe)_2](\mu-bpe)}(NO_3)_4}_n$ is prepared ; its structure is strikingly characterized by heptacoordinate Cd ions as well as by a unique main framework.

• Journal of the Korean Chemical Society
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• v.52 no.6
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• pp.727-733
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• 2008

• Journal of the Korean Chemical Society
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• v.46 no.3
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• pp.213-218
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• 2002

(${\eta}$5-Cyclopentadienyl)(${\eta}$6-1,2,3,4-tetramethyl-1,4-dibora-2,5-cyclohexadiene)Ni (5) was synthe-sizedas a main product by the reaction of cyclopentadienyl(carbonyl)nickel dimer and 1,2,3,4-tetramethyl-1,4-di-bora-2-cyclohexene (1). Di-allyl nickel reacted with 2,3-diethyl-1,4-di-methyl-1,4-dibora-2-cyclohexene (2) at -20$^{\circ}C$ to give bis(${\eta}$6-2,3-diethyl- 1,4-dimethyl-1,4-dibora-2,5-cyclohexadiene)nickel (6) in the yield of 15%. By the reaction of di-allyl nickel and 2,3-dimethyl-1,4-diethoxy-1,4-di- bora-2-cyclohexene (3) at -20$^{\circ}C$ bis[${\eta}$6-2,3-dim-ethyl-1,4-diethoxy-1,4-di- bora-2,5-cyclohexadiene]nickel (7) was obtained in 22% yield. These double-decker complexes were difficult to separate because of their unstabilities and were identified by ESR, NMR, MS and ele-mental analysis, etc.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.633-638
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• 2008

The bunsen reaction, part of IS(Iodine-sulfur) cycle that one of the hydrogen production by the thermochemical water splitting, was investigated. It was observed that $H_2SO_4$ was uniformly generated and generation of $H_2SO_4$ was independent of iodine input. However, generation of HI was decreased with increasing iodine input. It was thought that HI and unreacted iodine were formed complex compound such as $HI_3$ $HI_5$ or $HI_7$. The complex compound accelerated liquid-liquid separation properties in the product. It was also revealed that reaction kinetics was increased with increasing iodine input. Liquid-liquid separation properties were improved with increasing iodine input and reaction temperature. Moreover, no side reaction was occurred at all reaction conditions.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.629-635
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• 2012

This study was conducted to evaluate the removal behaviors of DOM(dissolved organic matter) and phosphorus in eutrophic lake water by coagulation process with PAC(powdered activated carbon). It was observed that the removal characteristic of soluble matter was different from that of dissolved one, and the removal of DOM was effected by both pH and coagulant dosage. It was founded that PAC could increase the removal efficiency by an adsorption of DOM in coagulation process. A formation of soluble and colloidal matters resulted in the degradation of phosphorus removal efficiency in a chemical precipitation process. The phosphorus removal efficiency could be enhanced by an absorption of colloidal matter and dissolved complex with PAC addition. In addition, the PAC addition caused the increase of floc density in coagulation process, that led to the rise of sedimentation rate, and resulted in a significant improvement of solid-liquid separation efficiency.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.569-574
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• 1991

Six free base porphyrins were synthesized by reacting pyrrole with benzaldehyde or its derivatives and then reacted with metal chlorides to prepare corresponding metal complexes. In addition, polymer-bonded porphyrins were synthesized by treating chloromethylated styrene-divinyl benzene (1%) copolymer beads with meso-tetra (p-aminophenyl)porphyrin (TNPP) solution and then treated with cupric chloride to obtain Cu(Res-NH-TPP-$NH_2$). The porphyrin compounds were characterized by visible, inffrared and electron spin resonance spectral analyses. The metal contents of metalloporphyrins were determined by atomic adsorption spectrophotometry. The synthesized porphyrin compounds were subsequently examined for their catalytic strength and found the activity to increase in the following order: free base porphyrins; metalloporphyrins; polymer-bonded metalloporphyrin. Among metalloporphyrins, Cu-TNPP showed the greatest catalytic power.

• Journal of the Korean Chemical Society
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• v.30 no.1
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• pp.76-83
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• 1986

Four oxovandium(IV) complexes with carboxylate ligands, $VO(picn)_2$, $VO(htmq)_2$, $VO(quin)_2$ and $VO(pyra)_2{\cdot}2H_2O)$ have been prepared and studied. Infrared spectral data coupled with the results of magnetic susceptibility study strongly suggest that there are relatively strong intermolecular interactions in $VO(picn)_2$ and $VO(htmq)_2$. In all oxovanadium(IV) complexes studied in this work, the carboxylate ligand coordinates to the metal ion in the unidentated fashion. Some fundamental vibration modes of oxovanadium(IV) complexes were empirically assigned from the difference in the spectrum of metal complex with free ligand.

• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.257-265
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• 2009

The structures and metal affinities of the binding configurations of $Cu^{+}$ and $Cu^{2+}$ to proline have been investigated using the hybrid three-parameter Density Functional Theory(DFT/B3LYP). We found that the metal-proline bonding and the energy ordering of several conformers were very different in $Cu^{+}$-proline and $Cu^{2+}$-proline. For $Cu^{+}$-proline, the ground state structure was found to have a bidentated coordination in which $Cu^{+}$ was coordinated to the carbonyl oxygen and imino group nitrogen of neutral proline. On the contrary, the ground state structure of $Cu^{2+}$-proline involves chelation between the two oxygens of the carboxylate group in a zwitterionic proline. The metal ion affinity of proline of the most stable $Cu^{+}$-proline complex was calculated as 76.0 kcal/mol at 6-311++G(d,p) level, whereas the $Cu^{2+}$ ion affinity of proline was calculated as 258.5 kcal/mol.

• Journal of the Korean Chemical Society
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• v.38 no.12
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• pp.857-863
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• 1994

The absorption and fluorescence spectroscopic studies on the interaction between thionine (TH) and sodium dodecyl sulfate (SDS) have been carried out. The absorption and fluorescence spectral changes of TH with the changes of concentration of SDS are interpreted in terms of i) the aggregation of TH-SDS complex, ii) the stacking process of dye molecules by the association of the TH-SDS complex, iii) breakdown of the stacking due to the formation of dye-rich induced micelles, iv) redistribution of dye molecules in the surface of SDS micelles.

• Journal of Environmental Science International
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• v.12 no.4
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• pp.497-501
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• 2003

The new tridentate ligands of nitrogen donor atoms N,N-Bis(2-amino-ethyI)-benzyl-amine 2HCI(BABEA. 2HCI) and 2,6-Bis(amino-methyl)-pyridien. 2HCI(BAMP. 2HCI) were synthesized as their dihydrochloride salts and characterized by TA, IR. Mass and NMR spectroscopy. The protonation constants of the ligands and stability constants for Cd$^{2+}$, Pb$^{2+}$, Zn$^{2+}$and Cu$^{2+}$ ions were determined by potentiometric titration in aqueous solutions and compared with those of analogous ligands. The effect stability constants of ligands and metal ions for removal of heavy metals in aqueous solution were described.