• Journal of Environmental Science International
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• v.27 no.1
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• pp.1-10
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• 2018

A continuous process of persulfate oxidation and citric acid washing was investigated for ex-situ remediation of complex contaminated soil containing total recoverable petroleum hydrocarbons (TRPHs) and heavy metals (Cu, Pb, and Zn). The batch experiment results showed that TRPHs could be degraded by $Fe^{2+}$ activated persulfate oxidation and that heavy metals could be removed by washing with citric acid. For efficient remediation of the complex contaminated soil, two-stage and three-stage processes were evaluated. Removal efficiency of the two-stage process (persulfate oxidation - citric acid washing) was 83% for TRPHs and 49%, 53%, 24% for Cu, Zn, and Pb, respectively. To improve the removal efficiency, a three-stage process was also tested; case A) water washing - persulfate oxidation - citirc acid washing and case B) persulfate oxidation - citric acid washing (1) - citric acid washing (2). In case A, 63% of TRPHs, 73% of Cu, 60% of Zn, and 55% of Pb were removed, while the removal efficiencies of TRPHs, Cu, Pb, and Zn were 24%, 68%, 62%, and 59% in case B, respectively. The results indicated that case A was better than case B. The three-stage process was more effective than the two-stage process for the remediation of complex-contaminated soil in therms of overall removal efficiency.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.6-10
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• 1998

The complex[Cu(L)](ClO4)2 (1) (L:3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized and structurally characterized. The complex 1 crystallizes in the monoclinic system, space group P21/n with cell parameters a=8.208(2)Å, b=13.339(6) Å, c=10.752(5) Å, β=111.02(4)˚ Z=2. Least-squares refinement of 1 led to a R(RW)factor of 0.073 (0.142) for 617 observed reflections of F0>40(F0). The crystal structure of 1 has a square-planar geometry and adopts the trans-III conformation.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.49-52
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• 2011

A dinuclear copper(II) complex of [$Cu_2(aceace)_4$(dipyph)] [aceace = acetylacetone, dipyph = 1,4-di(4-pyridylethene-2-yl-)benzene] has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. It crystallizes in the monoclinic system, space group P21/c, with lattice parameters a = 7.9584(16) $\AA$, b = 18.594(4) $\AA$, c = 15.063(4) $\AA$ $\beta=120.97(2)^o$ and $M_r$ = 807.85 ($C_{40}H_{44}Cu_2N_2O_8$), Z = 2. Each of the $Cu^{2+}$ ion adopts a square pyramid geometry and coordinates with four oxygen atoms from two aceace ligands and one nitrogen atom from dipyph bidentate ligand. Magnetic measurement shows that the Weiss constant and Curie constant for the title compound are -0.22 K and 0.1154 emu K/mol, respectively. Thermal stability data indicate that the title complex undergoes two steps decomposition and the residue is $Cu_2O_4$. In the potential range of -1.5 ~ 0.8 V, the title complex represents an irreversible electrochemical process.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.68-68
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• 2011

A new chemosensor based on rhodamine B (1) for $Hg^{2+}$ and $Cu^{2+}$ was synthesized by one-step condensation reaction of rhodamine B hydrazide and Azo dye. Studying for its fluorogenic and colorimetric behaviors towards various metal ions, extreme sensitivity and selectivity were achieved by the detection of $Hg^{2+}$ and $Cu^{2+}$ over other commonly coexistent metal ions, which were accompanied by ring opening of a rhodamine spirocycle framework. In acetonitrile, the presence of $Hg^{2+}$ and $Cu^{2+}$ induces the formation of a Dye 1-ion complex, which was deduced by spectroscopy.

• Korean Journal of Crystallography
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• v.17 no.2
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• pp.46-50
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• 2006

The dinuclear copper(II) complex {[Cu(pmea)Cl][Cu$(H_2O)_3]}Cl_2{\cdot} H_2O$ (1) (Hpmea=bis(2-pyridvlmethyl)amino-2-ethanoic acid) has been synthesized and characterized. It crystallizes in the monoclinic system $P2_1/c$, a=9.0008(6) ${\AA}$, b=28.0171(19) ${\AA}$, c=8.5590(6) ${\AA}$, $\beta$=104.2280(10)$^{\circ}$, V=2092.2(2) ${\AA}^3$, Z=4. Crystal structure of 1 reveals a syn-anti carboxylate-bridged dinuclear complex, in which the coordination environment around each copper atom exhibits a distorted square-pyramid and a distorted square plane, respectively.

• Bulletin of the Korean Chemical Society
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• v.26 no.4
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• pp.594-598
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• 2005

Treatment of a solution of $CuCl_2$ in dimethyl phosphate (DMP) with DMSO under nitrogen atmosphere afforded to a light blue fluorescence powder. Slow evaporation of $H_2O$-DMSO solution of this powder resulted in blue-sky crystals of a new polymeric Cu(II) complex, with a unit cell composed of $Cu_2(DMP)_4$(DMSO), (1). The crystal and molecular structure of the complex acquired crystallographically. Compound (1) crystallizes in the monoclinic space group $P2_1$/n with a = 12.8920(11) $\AA$, b = 13.1966(11) $\AA$, c = 14.7926(13) $\AA$, $\alpha$ = 90$^{\circ}$, $\beta$ = 98.943(2)$^{\circ}$, $\gamma$ = 90$^{\circ}$, V= 2486.1(4) ${\AA}^3$, and Z = 4. A square pyramidal environment for the metal center was established by coordination of oxygen atoms of four bridging DMP ligands in the basal positions and binding a tri-centered oxygen atom of DMSO in the apical disposition of Cu(II). The sixth position was also affected by a weak interaction with the sulfur atom of another DMSO. The phosphorous atom in the bridging DMP was arranged in a deformed tetrahedron with (gg) conformation for methyl esters with $C_{2v}$ symmetry.

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.281-286
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• 1990

The kinetics and mechanism of reduction of Cu(II) with an excess D-penicillamine have been examined at pH = 6.2 and 0.60M in ionic strength. The reaction at the initial stage is biphasic with a rapid complexation process to give "red" transient complex of $[Cu(II)(pen)_2]^2$- that is partially reduced to another transient "brown" intermediate. The "brown" intermediate is finally reduced to diamagnetic "yellow" complex, $[Cu(I)(Hpen)]_n$. The final reduction process is pseudo-first order in ["brown" transient] disappearance $with {\kappa} = {{\kappa}_{3a} + {\kappa}_{3b}[pen]^{2-}},$ where ${\kappa}_{3a} = (5.0{\pm}0.8){\times}10^{-3}sec^{-1}$ and ${\kappa} = (0.14{\pm}0.02) M^{-1}sec^{-1}$ at $25^{\circ}C$. The activation parameters for the $[H_2pen]$-independent and $[H_2pen]$-dependent paths are ${\Delta}H^{\neq} = (52{\pm}5)kJmol^{-1},$ and ${\Delta}S^{\neq} = ( - 27{\pm}3)JK^{-1}mo^{l-1},$ and ${\Delta}H^{\neq} = (56{\pm}2)kJmol^{-1}$ and ${\Delta} S^{\neq} = ( - 18{\pm}0.7)JK^{-1}mol^{-1}$ respectively. The nature of "brown" intermediate is not clearly identified, but this intermediate seems to be in the mixed-valence state, judging from the kinetic and spectroscopic informations.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2900-2904
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• 2013

We present the synthesis and characterization of DTPA-bis(histidylamide) (1a), DTPA-bis(aspartamide) (1b), and their gadolinium complexes of the type $[Gd(L)(H_2O)]$ (2a:L = 1a; 2b:L = 1b). Thermodynamic stabilities and $R_1$ relaxivities of 2a-b compare well with Omniscan$^{(R)}$, a well-known commercial, extracellular (ECF) MRI CA which adopts the DTPA-bis(amide) framework for the chelate: $R_1$ = 5.5 and 5.1 $mM^{-1}$ for 2a and 2b, respectively. Addition of the Cu(II) ion to a solution containing 2b triggers relaxivity enhancement to raise $R_1$ as high as 15.3 $mM^{-1}$, which corresponds to a 300% enhancement. Such an increase levels off at the concentration beyond two equiv. of Cu(II), suggesting the formation of a trimetallic ($Gd/Cu_2$) complex in situ. Such a relaxivity increase is almost negligible with Zn(II) and other endogenous ions such as Na(I), K(I), Mg(II), and Ca(II). In vivo MR images and the signal-to-noise ratio (SNR) obtained with an aqueous mixture of 2b and Cu(II) ion in an 1:2 ratio demonstrate the potentiality of 2 as a copper responsive MRI CA.

• Analytical Science and Technology
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• v.13 no.2
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• pp.173-178
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• 2000

A new open-chain ligand containing two phenol groups, 1, 14-Bis (2-hydroxybenzyl)-2, 6, 9, 12-tetraazatetradecane(bsated) was synthesized as its tetrahydrochloride salt and characterized by elemental analysis, mass, infrared and NMR. Its proton dissociation constants ($logK^n{_H}$) and stability constants ($logK_{ML}$) toward $Co^{2+}$, $Ni^{2+}$, $Cu^{2+}$ and $Zn^{2+}$ were determined at $25^{\circ}C$ and 0.10M($KNO_3$) ionic strength in aqueous solution by potentiometry. The X-ray structure of its copper (II) complex [Cu(bsated)]$(ClO_4)_2$ was reported: Monoclinic space group $P2_1/n$, $a=17.856(4){\AA}$, $b=17.709(1){\AA}$, $c=8.539(2){\AA}$, $V=2700(2){\AA}$ with Z=4. Electrochemical studies of [Cu(bsated)]$(ClO_4)_2$ complex in dimethyl sulfoxide (DMSO) solution containing tetrabutylammonium perchlorate (supporting electrolyte) were carried out by cyclic voltammograms (CV) and normal pulse voltammetry (NPV).

• Bulletin of the Korean Chemical Society
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• v.22 no.4
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• pp.379-382
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• 2001

A new ligand containing the long aliphatic hydrocarbon chain, dipyridylstearylamine (dps) and its copper(Ⅱ) complex, Cu(dps)(NO3)2 have been prepared. The copper complex was characterized structurally and spectroscopically. The XRD crystal structure of the copper complex reveals that copper is octahedrally coordinated by dps and two nitrato ligands. The nitrato groups ligate asymmetrically to the copper. Crystal data are P1bar, a=8.249(2), b=10.416(3), $c=20.915(4)\AA$, $\alpha=86.54(2)$, $\beta=84.026(2)$, $\gamma=72.32(2)^{\circ}$, V=1702.7(7) $\AA3$ , Z=2, ${\lambda}$(Mo $K\alpha)=0.71073\AA$, $\mu=0.689$ mm-1 , T=293(2) K, R=0.0560 for 3529 reflections. The dps and the copper complex are stable in the air and the copper complex exhibits features of typical of other copper(Ⅱ) complexes containing dipyridylamine-based ligand.