• Korean Journal of Soil Science and Fertilizer
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• v.36 no.4
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• pp.210-217
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• 2003

An alternative method to the empirical approach such as Langmuir and Freundlich model, surface complexation model using thermodynamic database is used to simulate adsorption behavior of cadmium for oxide minerals. Sorption of cadmium onto amorphous silica ($SiO_2$) and synthetic goethite (${\alpha}$-FeOOH) at various conditions of pH, initial cadmium loading, oxide concentration, and ionic strength, were investigated. For both oxide minerals, increasing cadmium concentration resulted in right shifting of the sorption curve of cadmium as the function of pH. The $pH_{50}$, where 50% of cadmium sorbed, of goethite (pH 5.25) was much smaller than that of the silica (pH 7.83). The sorption of cadmium onto both minerals were not affected by the background ion strength from $10^{-1}$ to $10^{-2}$ M of $KNO_3$. It indicated that the binding affinity of goethite surface for cadmium is much stronger than that of silica. The strong affinity of oxide mineral for cadmium can be explained by the existence of coordination or covalent bond between cadmium and surface of it.

• Membrane Journal
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• v.13 no.4
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• pp.211-218
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• 2003

The removal characteristics of cadmium in micellar enhanced ultrafiltration (MEUF) were investigated by using an anionic biosurfactant, deoxycholic acid (DCA). The ultrafiltration experiments were performed in a batch-type stirred cell. The ultrafiltration membranes used were Millipore YM1, YM3, YM10, and YM30 which had a difference in molecular weight cut-off. The presence of cadmium ion in DCA solution tends to reduce the critical micell concentration considerably and increase the micell size. The molecular weight cut-off of ultrafiltration membrane had a minimal effect on cadmium removal whereas DCA/Cd ratio had a substantial influence. When DCA/Cd ratio was 3, the removal efficiency of cadmium was more than 99.6%. A relative flux, which is defined as ratio of the flux for a separation trial to that of deionized water run using the same piece of membrane, decreased in the order of YM3 > YM1 > YM10 > YM30.

• Journal of the Korean Chemical Society
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• v.29 no.6
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• pp.637-645
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• 1985

To predict speciation of copper and cadmium in natural waters, the stability constant of complexes formed between copper or cadmium and natural organic ligands have been determined by the ion selective electrodes at pH 6. The stability constants for copper and cadmium, log $K'_{CuL} = 5.80\;and\;log K'_{CdL}=3.82$, were incorporated inot MINEQL computer program and prediction of chemical species of copper and cadmium in a model fresh water system was made by using this computer program. The natural organic ligands form complex with cupric ions at the concentration of $10^{-6}$ moles/l and with cadmium ions at the concentration of $10^{-5}$ moles/l. This result showed that prediction of chemical species of heavy metals in natural waters was not possible without taking into account the presence of the natural organic ligands.

• The Korean Journal of Mycology
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• v.19 no.4
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• pp.282-284
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• 1991

The yeast, Hansenula anomala B-7, isolated from the $Cd^{2+}$ rich soils and determined to be tolerant in the high concentration of $Cd^{2+}$ were employed in this work. Its intact cells grown in high concentration of $Cd^{2+}$ were observed to be Iysed at the early stage when transferred to a cadmium deficient broth. Its intact cells found to be not Iysed and grow well under the high concentration of $Cd^{2+}$. The Iysis of the intact cells grown at the high concentration of $Cd^{2+}$ ion was not found when the metal ions were replaced with $Cd^{2+}$ ion in the same concentration. This result indicated that Iysis of yeast cells, at least in this isolate, would be related to cell osmosis with the mineral ions added.

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.498-503
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• 2006

Adsorption features of $Cd^{2+}$ on waste tire particles have been investigated for the purpose of enhanced wastes recycling along with the development of an economic process for wastewater treatment. The isoelectric point of waste tire particles was found to be ca. pH 7 and the adsorbed amount of $Cd^{2+}$ was increased with pH under experimental conditions. The variation of the adsorption behavior of $Cd^{2+}$ with pH was well explained by the change of the electrokinetic potential of waste tire particles according to the pH. Adsorption of $Cd^{2+}$ was observed to reach its equilibrium within 45 minutes after the adsorption started under experimental conditions and followed the Freundlich model well. Kinetic analysis showed that the adsorption reaction of $Cd^{2+}$ was second order and thermodynamic estimation substantiated the endothermic behavior of $Cd^{2+}$ adsorption. As the amount of adsorbent increased, more adsorption of $Cd^{2+}$ was accomplished and the adsorption capacity of adsorbent was found to be enhanced by its pre-treatment with NaOH. Also, the adsorption of adsorbate was promoted as the ionic strength of wastewater was increased.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.101-109
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• 2008

The adsorption characteristics of cationic metals such as copper, cadmium, and lead onto the amorphous aluminum oxide, AMA-L, which was mineralized from raw sanding powder at $550^{\circ}C$ were investigated. Additionally, surface complexation reaction of cationic heavy metals onto AMA-L was simulated with MINEQL + software employing a diffuse layer model. From the batch adsorption tests in a single element system, the adsorption affinity of each metal ion onto AMA-L was following order: lead > copper > cadmium. In a binary system composed with copper and cadmium, quite a similar adsorption affinity was observed in each metal ion compared to the single element system. When the surface complexation constants obtained in the single system were used in the prediction of experimental adsorption results, model predictions were well fitted with experimental results of both single and binary systems.

• Journal of fish pathology
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• v.24 no.2
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• pp.141-152
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• 2011

Growth, oxidative stress and antioxidant capacity of Fucus serratus exposed to high doses of Cd were examined. Two sites in Southwest England (Restronguet Point and Bantham Quay) were selected since they had different histories of metal contamination. 1~10 mg Cd $L^{-1}$ were treated to Aquil medium for up to 14 days. Similar levels of lipid peroxidation but different values of relative growth rates, cupric ion reducing antioxidant capacity (CUPRAC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging capacity indicated that F. serratus has population-dependent antioxidant strategies. F. serratus demonstrated cadmium resistance with no visual symptoms for 14 days and the population from the polluted area seemed to have more powerful antioxidant strategies. However Fucus from the conserved area also showed protective anti oxidative mechanism.

• YAKHAK HOEJI
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• v.54 no.1
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• pp.13-21
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• 2010

The interaction of cadmium (II) ion with quercetin, qurecitrin and (+)-catechin was investigated in aqueous solution at various pH. The flavonoid/cadmium stochiometries for cadmium (II) binding to flavonoid have been determined by UV-visible spectroscopy. 1:1 Cd(II)-Flavonoid complex had a maximum absorbance and showed the bathochromic shift of the long-wavelength band of the UV-vis spectra in the alkaline pH, that occurs upon complexation, is due to a ligand-tometal charge transfer. The optimal concentration of Cd(II)-flavonoid complexes showed that complexation reaction could be classified in the following way: 55.27 ${\mu}M$ catechin > 54.72 ${\mu}M$ quercetin > 53.52 ${\mu}M$ quercitrin at the chelating site level. These results suggest that Cd(II)-flavonoid complex has the optimal condition of chelation in 0.2 M $NH_3$ - 0.2 M $NH_4Cl$ (pH 8.0) solution.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.72-75
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• 2009

In this paper, lithium-ion-polymer battery based standalone photovoltaic energy storage is presented. conventional system was difficult to choose hi-directional DC-DC converter because of unbalanced voltage of batteries. The other side, lithium-ion-polymer battery hardly contains unbalanced voltage between each batteries. And Lithium Polymer Battery is clean battery because is doesn't contain heavy metals such as Nickel, Cadmium. We analyzed validity of algorithms according to load pattern for the system through the simulation and experimental results.

• The Korean Journal of Mycology
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• v.21 no.1
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• pp.23-27
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• 1993

Ion effects on $11{\alpha}-hydroxylation$ of progesterone and $5{\alpha}-reduction\;of\;11{\alpha}-hydroxyprogesterone$ by Rhizopus nigricans were investigated. Metal ions such as $Cu^{2+},\;Cd^{2+},\;Co^{2+},\;Mn^{2+},\;Zn^{2+},\;Fe^{2+},\;Mg^{2+},\;Fe^{3+}\;and\;Na^+$ reduced the $11{\alpha}-hydroxylation$ activity, while $K^+$ stimulated the same reaction. Enzyme activity for the $5{\alpha}-reduction$ of $11{\alpha}-hydroxyprogesterone$ was increased in the presence of $Fe^{2+},\;Mn^{2+},\;Mg^{2+},\;Co^{2+},\;Zn^{2+},\;Fe^{3+},\;K^+\;and\;Na^+$, whereas it was decreased in the presence of $Cd^{2+}\;and\;Cu^{2+}$. Potassium ion of $10^{-3}\;M\;$ of concentration was found to be effective for the promotion of $11{\alpha}-hydroxylation$. On the other hand, cadmium ion of $10^{-4}\;M$ was proved to suppress the $5{\alpha}-reduction$ reaction. Progesterone is reported to be transformed into $11{\alpha}-hydroxyprogesterone$ which, in turn, is converted further into $11{\alpha}-hydroxy-allopregnane-3$, 20-dione by R. nigricans. From this point of view, the highest yield of $11{\alpha}-hydroxyprogesterone$ could be obtained when potassium ion of $10^{-3}\;M$ was given initially followed by addition of cadmium ion of $10^{-4}\;M$ to limit conversion of 11{\alpha}-hydroxyprogesterone into $11{\alpha}-hydroxy-allopregnane-\;3$, 20-dione.