• Applied Chemistry for Engineering
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• v.30 no.1
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• pp.54-61
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• 2019

In this study, a magnetic adsorbent was synthesized by growing ferrite nanoparticles substituted with metals (Me = Co, Mn, Ni) on zeolite 4A for the efficient separation of waste adsorbents present in the solution after the adsorption of Cu(II). The metal ferrite grown on the surface of zeolite was prepared by solvothermal synthesis. Characteristics of the magnetic adsorbent were analyzed by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and physical property measurement system (PPMS). The saturation magnetization of the A type zeolite coated with Co-ferrite (CFZC) was the highest at 5 emu/g and the Cu(II) adsorption performance was also excellent. The adsorption results of Cu(II) on CFZC were well fitted by the Langmuir model at 298 K. Also, the adsorption of Cu(II) on CFZC follows a pseudo-second order kinetic. The Gibbs free energy values (${\Delta}G^0$) ranging from -4.63 to -5.21 kJ/mol indicates that the Cu(II) adsorption is spontaneous in the temeprature range between 298 and 313 K.

• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.1-8
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• 2000

In order to explore the potential of ascorbic acid supplementation for the prevention and treatment of herpes simplex viral diseases, plaque reduction assays were performed. Ascorbic acid as well as copper chloride/ferric chloride were added to wells containing Vero cells infected with herpes simplex virus type 1 (HSV-1), and the infectivity of HSV-1 was determined. Since copper and iron are major transition metals in human plasma, near the normal human plasma concentrations of them were used for experiments. When Cu(II) and Fe(III) were applied, there were no significant differences between virus control and Cu(II)/Fe(III)-treated groups. But, when appropriate concentrations of ascorbic acid were added to wells, meaningful differences between control and ascorbate-treated groups were found. In the presence of Cu(II)/Fe(III) at $5.8/3.7\;{\mu}M$, 72-h treatment with ascorbate at $50\;{\mu}M$ reduced HSV-1 infections to $10.77%{\pm}4.25%$ (P < 0.001) and $500\;{\mu}M$ did to $3.06%{\pm}1.62%$ (P < 0.001). Moreover, the cytotoxicities for Vero cells at those concentrations were insignificant (P > 0.05). Current recommended dietary allowance (RDA) of ascorbic acid is 60 mg/day, and the oral intake of 60 mg/day of ascorbic acid yields plasma ascorbic acid at 45 to $58\;{\mu}M$ in a healthy adult man. Therefore, the results of this study suggest that the maintenance of appropriate level (more than $50\;{\mu}M$) of ascorbic acid in human plasma by appropriate amount (more than the RDA) of ascorbic acid supplementation may be helpful for the prevention and treatment of diseases caused by HSV -1 in an adult man. In addition, this study also suggests that ascorbic acid may be useful for the prophylaxis of fatal HSV-1 infections in neonates and the prevention of HSV-1 reactivation in immunocompromised hosts.

• Journal of the Korean Chemical Society
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• v.39 no.4
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• pp.281-287
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• 1995

Copper(Ⅱ) complexes with N,N'-oxalylbis(salicylaldehydehydrazone), N,N'-malonylbis(salicylaldehydehydrazone) and N,N'-succinylbis(salicylaldehydehydrazone) have been prepared in 95% DMF. Their protonation and stability constants were investigated by potentiometric titration. We observed that MBSH ligand showed the largest protonation constant. The values of the protonation constants among three different ligands were increased as following order SBSH < OBSH < MBSH. However, the increasing order of stability constants was somewhat different such as Cu(Ⅱ)-SBSH < Cu(Ⅱ)-MBSH < Cu(Ⅱ)-OBSH. In addition, thermodynamic parameters, ΔH and ΔS of Cu(Ⅱ) complexes have been studied. As a result, we found the SBSH ligand produced the best stable copper (Ⅱ) complex.

• Journal of Environmental Science International
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• v.24 no.1
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• pp.1-7
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• 2015

The solid-phase extractant PS-D2EHPA/TBP was prepared by immobilizing two extractants D2EHPA and TBP in polysulfone (PS). The prepared PS-D2EHPA/TBP was characterized by using fourier transform infrared spectrometer (FTIR) and scanning electron microscopy (SEM). The removal of Cu(II) from aqueous solution was investigated in batch system. The experiment data were obeyed the pseudo-second-order kinetic model. Equilibrium data were well fitted by Langmuir model and the removal capacity of Cu(II) by solid extractant PS-D2EHPA/TBP obtained from Langmuir model was 3.11 mg/g at 288 K. The removal capacity of Cu(II) was increased according to increasing pH from 2 to 6, but the removal capacity was decreased below pH 3 remarkably.

• Journal of Environmental Science International
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• v.24 no.7
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• pp.841-849
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• 2015

The solid phase extractant SAN-D2EHPA/TBP containing two extractants of Di-(2-ethylhexyl)phosphoric acid (D2EHPA) and Tri-butyl-phosphate (TBP) was prepared by immobilizing two exractants D2EHPA and TBP in styrene acrylonitrile copolymer (SAN). The prepared SAN-D2EHPA/TBP was characterized by using fourier transform infrared spectrometer (FTIR) and scanning electron microscopy (SEM). The solid phase extractant SAN-D2EHPA/TBP was tested for the removal of Cu(II) from aqueous solution. Experiments were carried out as a function of the pH and Cu(II) concentration in the aqueous phase. The equilibrium time was 180 min and equilibrium experiment data obeyed the pseudo-second-order kinetic model. The Langmuir isotherm model represented the experiment data as well. The maximum removal capacity of Cu(II) calculated from Langmuir isotherm model was 3.1 mg/g.

• Journal of Environmental Science International
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• v.23 no.6
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• pp.1157-1163
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• 2014

The solid phase extractant (PVC-D2EHPA bead) was prepared by immobilizing di-2-ethylhexyl-phosphoric acid (D2EHPA) with polyvinyl chloride (PVC). The prepared PVC-D2EHPA beads were characterized by using fourier transform infrared spectrometer (FTIR) and scanning electron microscopy (SEM). The removal experiments of Cu(II) by PVC-D2EHPA beads conducted batchwise. The removal kinetics of Cu(II) was found to follow the pseudo-second-order model. The equilibrium data fitted well with Langmuir isotherm model and the maximum removal capacity was 2.6 mg/g at $20^{\circ}C$. The optimum pH region was in the range of 3.5 to 6. and the standard free energy (${\Delta}G^{\circ}$) was between -4.67~-4.98 kJ/mol, indicating the spontaneous nature of Cu(II) removal by PVC-D2EHPA beads.

• Carbon letters
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• v.7 no.1
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• pp.1-8
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• 2006

The activated carbon "C" was obtained by carbonization followed by activation with steam at 40% of burn-off. Oxidized carbons C-N, C-P and C-H were obtained by oxidizing the activated carbon C with concentrated nitric acid, ammonium peroxysulfate and hydrogen peroxide, respectively. The textural properties of the carbons were determined from nitrogen adsorption at 77 K. The acidic surface functional groups were determined by pH titration, base neutralization capacity and electrophoretic mobility measurements. The cation exchange capacities of un-oxidized and oxidized carbons were determined by the removal of Cu(II) and Ni(II) from their aqueous solutions. The surface area and the total pore volume decreased but the pore radius increased by the treatment of activated carbon with oxidizing agents. These changes were more pronounced in case of oxidation with $HNO_3$. The surface pH of un-oxidized carbon was basic whereas those of the oxidized derivative were acidic. The removal of Cu(II) and Ni(II) was pH dependent and the maximum removal of the both ions was obtained at pH of 5-6. Cu(II) was more adsorbed, a phenomenon which was ascribed to its particular electronic configuration.

• Analytical Science and Technology
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• v.19 no.4
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• pp.309-315
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• 2006

Two piperazine-templated metal sulfate complexes, $(C_4N_2H_{12})[Ni(H_2O)_6](SO_4)_2$, I and ($C_4N_2H_{12}$) $[Co(H_2O)_6](SO_4)_2$, II, have been synthesized by hydro/solvothermal reactions and their crystal structures analyzed by single crystal X-ray diffraction methods. Complex I crystallizes in the monoclinic system, $P2_1/n$ space group, a=12.920(3), b=10.616(2), $c=13.303(2){\AA}$, ${\beta}=114.09(1)^{\circ}$, Z=4, $R_1=0.030$ for 3683 reflections; II: monoclinic $P2_1/n$, a=12.906(3), b=10.711(2), $c=13.303(2){\AA}$, ${\beta}=114.10(2)^{\circ}$, Z=4, $R_1=0.032$ for 4010 reflections. The crystal structures of the piperazine-templated metal(II) sulfates demonstrate zero-dimensional compound constituted by diprotonated piperazine cations, metal(II) cations and sulfate anions. The structures of complex I and II are substantially isostructural to that of the previously reported our piperazine-templated copper(II) sulfate complex $(C_4N_2H_{12})[Cu(H_2O)_6](SO_4)_2$. The central metal(II) atoms are coordinated by six water molecules in the octahedral geometry. The crystal structures are stabilized by three-dimensional networks of the $O_{water}-H{\cdots}O_{sulfate}$ and $N_{pip}-H{\cdots}O_{sulfate}$ hydrogen bonds between the water molecules and sulfate anions and protonated piperazine cations. Based on the results of thermal analysis, the thermal decomposition reactions of the complex I was analyzed to have three distinctive stages whereas the complex II proceed through several stages.

• Analytical Science and Technology
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• v.8 no.4
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• pp.457-460
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• 1995

A new hollow fiber filled with the lower refractive index liquid as core constructs a liquid core optical fiber(LCOF). The LCOF have been used as colorimetric cell to determine elements Cr and Cu in the presence of 70%- 50% ethanol or 50% dioxane aqueous solution, based on colored complex of Chromium(VI) with Diphenycarbazid(DPC) and copper with Chromaurd S(CAS) respectively. The sensitivity (1/ng/ml) of calibration curve of Cr and Cu are 0.052, 0.017 over the range 0 - 25, 0 - 24(ng/ml) respectively. The Cr in the animal gum and Nation Standard of China are determined with recoveries of 94 - 102%.

• Bulletin of the Korean Chemical Society
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• v.17 no.8
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• pp.688-693
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• 1996

Tetradentate Schiff base ligands derived from 2-hydroxy-1-naphthaldehyde and aliphatic diamine have been synthesized. Cu(Ⅱ) complexes of Schiff base ligands have been synthesized from the free ligands and copper acetate. The mole ratio of ligand to copper was identified to be 1:1 by the result of elemental analysis and Cu(Ⅱ) complexes were in a four-coordinated configuration. The electrochemical redox process of Cu(Ⅱ) complexes in a DMF solution has been investigated by cyclic voltammetry, chronoamperometry, differential pulse voltammetry, and controlled potential coulometry. The redox process of Cu(Ⅱ) complexes is one electron transfer process in quasi-reversible and diffusion-controlled reaction. The electrochemical redox potentials and the kinetic parameters of Cu(Ⅱ) complexes are affected by the chelate ring of Schiff base ligands.