• Korean Journal of Soil Science and Fertilizer
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• v.19 no.4
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• pp.307-314
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• 1986

Cu(II) binding mechanisms with water soluble organic fractions (WSOF) extracted from an agricultural soil (W), a soil treated with sludge for 6 years ($WS_6$), a sludge-soil mixture incubated for one week ($WS_1$), and sewage sludge (SS) were studied by electron spin resonance (ESR) spectroscopy and potentiometric titrations. Cu(II)-WSOF complexes produced $g_{11}$ values which were larger than $g_{\perp}$ values, indicating that the coordination of Cu(II) complex was an elongated octahedron. At liquid $N_2$ temperature (77K), the Cu(II)-W complex showed an anisotropic ESR spectrum while the Cu(II)-SS complex showed an isotropic spectrum. These spectral results suggest that the oxygen donor ligands of W may form relatively strong bonds with $Cu^{2+}$ due to extensive chelation while ligands of SS may form little or no chelate bonds with $Cu^{2+}$. The ESR spectra of Cu(II)-SS complex also suggest that each of four in-plane ligands (e.g., $COO^-$, $H_2O$, $Cl^-$, etc.) may act independently as monodentate ligands. Oxygen donor ligands such as aromatic carboxyl groups were probably the major Cu(II) binding sites in W. Sulfonate, aliphatic carboxyl group, and N-containing ligands were probably the major binding sites in SS at pH 5. The Cu(II) complexation with N-containing groups increased as sludge was added to the soil. Much higher (6x) pyridine concentrations were required to displace W from Cu(II)-W complex as compared to the Cu(II)-SS complex.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.246-253
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• 1998

Heavy metal-tolerant microorganisms, such as Pseudomonas putida, P. aeruginosa, P. chlororaphis and P. stutzeri which possessed the ability to accumulate cadmium, lead, zinc and copper, respectively, were isolated from industrial wastewaters and mine wastewaters polluted with various heavy metals. The binding sites of heavy metal in the cells were investigated by chemical modification of functional groups the cell walls. To determine the binding sites of heavy metal in the cells, electrochemical charge of amine and carboxyl groups in the cell walls of heavy metal-tolerant microorganisms were chemically modified. Chemical modifications of amine groups did not affect the heavy metal uptake as compared to native cell walls. In contrast, modifications of carboxyl groups drastically decreased heavy metal uptake as compared to native cell walls, and electron microscopy confirmed that the form and structure of the heavy metal uptake were different from those of native cell walls. The results suggested that the carboxyl groups were the major sites of heavy metal uptake in the heavy metal-tolerant microorganism cell.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.2 no.2
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• pp.149-158
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• 1998

Biomass of non-living brown seaweed Sargassun fluitans pretreated with NaOH is capable of taking up more than $10\%$ $(q_{max}$ : 3.85 mmol/g for Al and 1.48 mmol/g for Cu) of its dry weight in the Al and Cu at pH of 4.5. However, the maximum Al and Cu uptakes calculated from Langmuir isotherm were 1.58 mmol/g for Al and 1.35 mmol/g for Cu at pH 3.5. Equilibrium batch sorption study was performed using two-metal system containing Al and Cu. The mathematical model of the two-metal sorption system enabled quantitative estimation of one-metal biosorption inhibition due to the influence of a second metal. NaOH-treated S. fluitans contained 2.19 mmol $(43\;wt.\%)$ carboxyl groups per gram of biomass. A modified form of Langmuir, which assumes binding of Cu as $Cu^{2+}$ and Al as $Al(OH)_2^+,$ was used to model the experimental data. This result agrees with the one of mono-valent sorption for Al in single-metal system. The modified Langmuir model gives the following affinity correlated coefficients: 0.196 for Cu and 6.820 for Ah at pH 4.5, and 2.904 for Cu and 3.131 for Al at pH 3.5. The interference of Al in Cu biosorptive uptake was assessed by `cutting' the three dimensional uptake isotherm surfaces at constant second-metal final concentrations. Equimolar final equilibrium concentrations of Cu and Al of 1 mM at pH 4.5 give Cu and hi uptakes reduced by $82.5\%\;and\;5.4\%,$ respectively. However, these values at pH 3.5 were $55\%\;(Cu)\;and\;31\%$ (Al).

• Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.43-54
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• 2011

Gene structure of copper/zinc-superoxide dismutase (Cu/Zn-SOD; sod1) was characterized in Hemibarbus mylodon (Teleostei; Cypriniformes), an endangered freshwater fish species in Korean peninsula. Full-length cDNA of H. mylodon SOD1 consisted of a 796-bp open reading frame sequence encoding 154 amino acids, and the deduced polypeptide sequence shared high sequence homology with other orthologs, particularly with regard to metal-coordinating ligands. Genomic structure of the H. mylodon sod1 gene (hmsod1; 1,911 bp from the ATG start codon to the stop codon) was typical quinquepartite (i.e., five exons interrupted by four introns); the lengths of the exons were similar among species belonging to various taxonomic positions. The molecular phylogeny inferred from sod1 genes in the teleost lineage was in accordance with the conventional taxonomic assumptions. 5'-flanking upstream region of hmsod1, obtained using the genome walking method, contained typical TATA and CAAT boxes. It also showed various transcription factor binding motifs that may be potentially involved in stress/immune response (e.g., sites for activating proteins or nuclear factor kappa B) or metabolism of xenobiotic compounds (e.g., xenobiotic response element; XRE). The hmsod1 transcripts were ubiquitously detected among tissues, with the liver and spleen showing the highest and lowest expression, respectively. An experimental challenge with Edwardsiella tarda revealed significant upregulation of the hmsod1 in kidney (4.3-fold) and spleen (3.1-fold), based on a real-time RT-PCR assay. Information on the molecular characteristics of this key antioxidant enzyme gene could be a useful basis for a biomarker-based assay to understand cellular stresses in this endangered fish species.

• Polymer(Korea)
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• v.38 no.6
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• pp.801-808
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• 2014

Ion diffusion and chemical binding to acrylic polymer were investigated in a solid film. The composition of acrylic monomers containing amino group and carboxylic acid was adjusted for rapid ion migration in the film. p-Methylred (PMR) and phenolphthalein derivatives were optically sensitive to the concentration of proton and hydroxyl anion, respectively and verified the ion migration through the film layers. A rapid proton migration was observed in the film of a high amino content. On the other hand, $OH^-$ migration occurred rapidly in a high content of carboxylic acid group. The proton migration occurred through the internal layer as well as surface layer of a film and was reversible during 50 repetition examination. Copper(II) ion migration was examined with a Rhodamine-containing polymer film. The light absorption and emission spectra of a Rhodamine-Cu complex showed the key contribution of carboxylic acid group to the Cu(II) migration in a film.

• Korean Journal of Metals and Materials
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• v.49 no.8
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• pp.657-663
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• 2011

This study represents the results of the peel strength and surface morphology according to the preprocessing times of polyimide (PI) in a Cu/Ni/PI structure flexible copper clad laminate production process based on the polyimide. Field emission scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used to analyze the surface morphology, crystal structure, and interface binding structure of sputtered Ni, Cu, and electrodeposited copper foil layers. The surface roughness of Ni, Cu deposition layers and the crystal structure of electrodeposited Cu layers were varied according to the preprocessing times. In the RF plasma times that were varied by 100-600 seconds in a preprocessing process, the preprocessing applied by about 300-400 seconds showed a homogeneous surface morphology in the metal layers and that also represented high peel strength for the polyimide. Considering the effect of peel strength on plastic deformation, preprocessing times can reasonably be at about 400 seconds.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.4
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• pp.655-666
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• 1996

The effect of protease (subtilisin Carlsberg) on the removal of hemoglobin as protein soil was studied. The relation between the renloval and the hydrolysis of hemoglobin by subtilisin Carlsberg was discussed. The soiled babric was prepared by spotting of hemoglobin solution evenly on the cotton fabric and was denatured by steaming. The soiled fabric was washed by using Terg-0-Tometer at various conditions. The removal efficiency was evaluated by analysis of protein on the fabrics before and after washing by means of copper-Folin method. 1. The removal of hemoglobin was increased in proportion to increasing of the enzyme concentration up to a certain point, but it began to decrease above the point. 2. The hemoglobin was removed effectively by adding of subtilisin Carlsberg, and more effectively removed by adding of AOS in the enzyme solution. 3. The removal of hemoglobin deviated from the first order reaction in detergency. 4. The renloval of hemoglobin was highest at $50^{\circ}C$ in detergency, Even at low temperature the removal efficiency of enzyme was relatively higher compared with the hydrolysis of hemoglobin by the enzyme. However the removal of hemoglobin was apparently decreased with the increase of temperature over $60^{\circ}C$. 5. The removal of hemoglobin was relatively high at pH 7.0~8.0 and increased continuously with the increase of pH in detergency 6. In detergency, the removal mechanism of hemoglobin by subtilisin Carlsberg could be explained as follows: Fisrt of all, the enzyme hydrolyzed hemoglobin substrates partially by forming E-S complex at the surface of hemoglobin on the cotton fiber, and decomposed cooperative binding of hemoglobin. Subsequently, the fragments of hemoglobin were easily removed by washing. According as the enzyme penetrated to inner part of hemoglobin gradually, the hemoglobin on the cotton fiber was effectively removed by the repetition of these process. The removal of hemoglobin was more effectively increased by adding both the enzyme and AOS in the washing solution. Therefore, it was regarded that AOS molecules were adsorbed at the hydrophobic surface of denatured hemoglobin, subsequently, decomposed more effectively cooperative binding of hemoglobin, and the fragments of hemoglobin were removed more efficiently by means of the interfacial reaction of AOS.

• Analytical Science and Technology
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• v.20 no.5
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• pp.406-412
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• 2007

The formation of inclusion complexes between ${\beta}$-cyclodextrin and diethylenetriamine substituted-pyridine copper(II) perchlorate; [Cu(dien)(sub-py)] $(ClO_4)_2$, were studied by spectrophotometric methods. On account of charge-transfer band(MLCT) and $^2T_2{\rightarrow}^2E$, the two high peaks were observed as an inclusion complex for the [${\beta}$-CD]$[Cu(dien)(p-Cl-py)]^{2+}$ in the ultraviolet region of the spectrum. The ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion formed a 1:1 complex, and the formation constants were decreased with the increasing temperatures, due to weak binding energy between ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion. This reaction was controlled by enthalpy. In a correlation of the Hammett substituent constants and formation constants for the reaction, formation constants were increased by strong binding energy in the inclusion complexes when electron donating groups were substituted in pyridine ring.

• Journal of the Korean Society of Safety
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• v.30 no.1
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• pp.34-39
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• 2015

The feasibility of recycling wasted printed circuit board (PCB) is investigated by preparing PCB added flame retardant composites filled with either unsaturated polyester or polyurethane. In order to improve electroconductive properties, copper powder was added into the composites, which results also in improving their antistatic properties. The prepared composite samples showed a binding between the polymer fillers observed by a scanning microscope. The sample group using unsaturated polyester is elastomeric that led to appreciable elongation and elasticity. In case of polyurethane, the tensile strength increased proportionally as increase of the amount of PCB powder. The composite materials can be utilized as antistatic composite materials, since the surface resistivity result showed increase of the electroconductive properties by adding Cu. The flammability of the samples is not satisfactory according to UL-94 vertical test. However, the flame retardant properties were improved by adding PCB power. This study, therefore, showed that it is feasible to fabricate polymer composite materials and improve the material characteristics by adding PCB powder, which can replace existing additives used for the preparation of polymer composite materials and can reduce the environment contamination by recycling the wasted PCB.

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.4
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• pp.107-114
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• 2007

A study on the removal of heavy metals using alginic acid, a kind of polysaccharides, was performed. Alginic acid adsorbed 480 mg Pb/g dry mass at pH 4, which was about twice as high as uptake capacity of other biosorbents. Isothermal adsorption curve for lead ions was described by the Langmuir model equation and the experimental data well fitted to model equation. The adsorption of lead ions was an endothermic process since binding strength increased with temperature. The effect of alkali metal ions ($Ca^{2+}$ and $Mg^{2+}$) on lead sorption capacity was negligible and most adsorption process was completed in 30min. The uptake capacity of other metals such as, copper, mercury, strontium, and cesium ions using alginic acid was also investigated.