• Korean Journal of Environmental Agriculture
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• v.34 no.1
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• pp.21-29
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• 2015

BACKGROUND: Heavy metal adsorptionnot only depends on biochar characteristics but also on the nature of the metals involved and on their competitive behavior for biochar adsorption sites. The goal of this study was to investigate the competitive absorption characteristics of Cu and Cd in mono-metal and binary-metal forms by biochar derived from Phragmites communis. METHODS AND RESULTS: Batch and column experiments were conducted to evaluate the competitive adsorption characteristics of the biocharfor Cu and Cd. In the batch experiments, the maximum adsorption capacity of Cd(63 mg/g) by biochar was higher than that for Cu (55 mg/g) in the mono-metal adsorption isotherm. On the other hand, the maximum Cu adsorption capacity (40 mg/g) by biochar was higher than that for Cd(25 mg/g) in the binary-metal adsorption isotherm. Cu was the most retained cations. Cd could be easily exchanged and substituted by Cu. The amounts of adsorbed metals in the column experiments were in the order of Cd (121 mg/g) > Cu (96 mg/g) in mono-metal conditions, and Cu (72 mg/g) > Cd (29 mg/g) in binary-metal conditions. CONCLUSION: Overall, the results demonstrated that competitive adsorption among metals increased the mobility of these metals. Particularly, Cd in binary-metal conditions lost its adsorption capacity most significantly.

• YAKHAK HOEJI
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• v.58 no.3
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• pp.151-157
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• 2014

Water extracts of rice grasshopper (Oxya japonica japonica Thurnberg) were prepared and their antitumor and immunostimulatory activities were investigated using a flow cytometer. When LCT-CT was ip injected into ICR mice at the dose of 33.3 mg/kg before and after the implantation of $4{\times}10^5$ cells/mouse of sarcoma 180 tumor cells, it inhibited the growth of the tumor cells by 96.6%, showed lymphoblstogenic activities on the splenic lymphocytes and increased the expression of CD25 molecules on the splenic T lymphocytes. When co-cultured with the splenic lymphocytes of a BALB/c mouse, LCT-CT showed strong immunostimulatory activities at the concentration of $25{\sim}100{\mu}g/ml$ by significantly increasing lymphoblasts ratio and CD25 expression.

• Journal of the Korean Society of Food Culture
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• v.17 no.4
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• pp.456-464
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• 2002

This study was designed to investigates the effects of Korean pueraris radix water extract in Cd(cadmium) administered rats. Forty male Sprague-Dawley rats weighing $100{\pm}10g$ were used for this experiment and divided into following 4 groups; control group, 3% pueraria radix in water extract group, 50 ppm Cd group, 50ppm Cd group with 3% pueraria radix in water extract group. The Cd administered rats were given 50 ppm of $CdCl_2\;{\cdot}\;2H_2O$ disolved in the distilled water. The Cd content in the rats tissue of Cd administered group was lower than in the rats tissue of Cd group with 3% pueraria radix in water extract group. Plasma levels of renin activity was increased by Cd administration group, compared with 3% pueraria radix in water extract group and Cd administred group. Glutamate oxaloacetate transaminase(GOT) and Glutamate pyruvate transaminase(GPT) were increased in Cd-administered group and lower in the 3% extracts of pueraria radix in water extract group. Lactate dehydrogenase(LDHase) was lower in the 3% extracts of pueraria radix-Cd group than in the Cd group. This results suggested that pueraria radix in water extract group, has a lowering effects on the accumulation of Cd and it is belived that the pueraria radix in water extract group has some protective effects to Cd administered in rats, but the mechanism of these effects was obscure.

• Korean Journal of Environmental Biology
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• v.32 no.3
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• pp.243-249
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• 2014

In this study, we evaluated the toxic effects of heavy metals (Cd, Cu, Zn) on the population growth rate (r) of the marine diatom, Skeletonema costatum. S. costatum. The population growth rate (r) of the species was determined after 96 hrs. of exposure to Cd (0, 0.63, 1.25, 2.50, 5.00, 10.00 ppm), Cu (0, 0.25, 0.50, 0.75, 1.00, 1.25, 1.50 ppm) and Zn (0, 0.31, 0.63, 1.25, 2.00, 2.50, 5.00 ppm). It was observed that 'r' in the control (absence of Cd, Cu and Zn) were greater than 0.05, however suddenly decreased with increased heavy metal concentrations. Cd, Cu and Zn reduced 'r' in a dose-dependent manner and a significant reduction were occurred at concentration of greater than 1.25, 1.25 and 2.50 ppm, respectively. Based on the toxicity, the heavy metal were ranked as Cu>Zn>Cd, with EC50 values of 1.11, 2.13 and 6.84 ppm, respectively. The lowest-observed-effective-concentration (LOEC) of 'r' in exposed to Cd, Cu and Zn were 1.25, 1.00, 2.00 ppm, respectively. Precisely, a concentration of greater than 1.25 ppm of Cd, 1.00 ppm of Cu and 2.00 ppm of Zn in marine ecosystems induced toxic effect on the 'r' of S. costatum. Based on our results, we suggested that the 'r' of S. costatum might be a useful bio indicator for the toxicity assessment of heavy metals in marine ecosystems.

• Environmental Analysis Health and Toxicology
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• v.19 no.2
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• pp.141-151
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• 2004

We exposed juvenile puffer fish, Takifugu obscurus(30 days after hatching) to various aqueous pollutants including 4 kinds of inorganic metals (Ag, Cd, Cu and Hg), 2 organotin compound.; (tributyltin ［TBT］ and triphenyltin［TPhT］) and 5 polycyclic aromatic hydrocarbon (PAH) compounds (chrysene, fluoranthene, naphthalene, phenanthrene and pyrene) to estimate median lethal concentrations (LC50s) of each pollutant after the 96-hour acute exposure. Among the inorganic metals, Hg (52 $\mu\textrm{g}$/L; 96-h LC50) was most toxic to test animals and followed by Ag (164 $\mu\textrm{g}$/L), Cu (440 $\mu\textrm{g}$/L) and Cd (1180 $\mu\textrm{g}$/L). Aqueous TBT was more toxic between the two organotins; the 96-h LC50 for TBT (5.1 $\mu\textrm{g}$/L) was 3 times lower than that of TPhT (17.3 $\mu\textrm{g}$/L). The acute toxicity of PAH compounds was highest for chrysene (1.5 $\mu\textrm{g}$/L; 96-h LC50) and decreased in the order of pyrene (65 $\mu\textrm{g}$/L) > fluoranthene (158 $\mu\textrm{g}$/L) > phenanthrene (432 $\mu\textrm{g}$/L) > naphthalene (8690 $\mu\textrm{g}$/L). The toxicity of PAH compounds wat closely related to their physico-chemical characteristics such as $K_{ow}$ and water solubility, and well explained by simple QSAR relationship. The sensitivity of puffer fish to various inorganic and organic pollutants was generally comparable to various fish species widely used as standard test species in previous studies and further evaluation should be conducted to develop adequate testing procedure for T. obscurus when used in various toxicity tests.

• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.105-111
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• 1993

This study was carried out to find heavy metal contents in soil and in native plant in the regions near by zinc-mines, located at the Chilgok and Uljin Gun in Kyeongpook area. In the heavy metal contents during the to growth of native plants, Cd was contained in the order perennial > biennial > annual plant, but Cu was annual > perennial > biennial plant, and there was no difference in Zn contents. The native plants contained heavy metal highest were Osmunda japonica in Cd, Persicaria thunbergii H.G in Cu and Equisetum arvense L. in Zn. Cd was contained highest in Pteridaceae, Cu in Equisetaceae and Zn in Polygonaceae. In the heavy metal contents by the part of plant of Equisetum arvense L. and Erigeron canadensis, Cd and Zn were much contained in the order leaf > stem > root, but Cu was in the order root > leaf > stem. The average contents of Cd, Cu, Zn in soil were 1.27ppm. 12.04ppm. 64.28ppm in Chilgok, and 3.30ppm. 72.93ppm. 194.04ppm in Uljin respectively. There were positive correlations between Cd contents of heavy metals(Cd, Cu, Zn) in soil and in native plant, but not significant. It was estimated that Osmunda japonica, Pteridium aquilinum (KUHN) var and Equisetum arvense L. which most absorbed heavy metal have effect of exclusion of heavy metals near by zine-mines region.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.2
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• pp.267-275
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• 2015

In this paper, ZnO films were prepared by atomic layer deposition (ALD) and CdS films were deposited using chemical bath deposition (CBD) to form ZnO/CdS heterojunction. More accurate mapping of band arrangement of the ZnO/CdS heterojunction has been performed by analyzing its electrical and optical characteristics in depth by various methods including transmittance, x-ray photoemission spectroscopy (XPS), and ultraviolet photoemission spectroscopy (UPS). The optical bandgap energies ($E_g$) of ZnO and CdS were 3.27 eV and 2.34 eV, respectively. UPS was capable of extracting the ionization potential energies (IPEs) of the materials, which turned out to be 8.69 eV and 7.30 eV, respectively. The electron affinity (EA) values of ZnO and CdS calculated from IPE and $E_g$ were 5.42 eV and 4.96 eV, respectively. Energy-band structures of the heterojunction could be accurately drawn from these parameters taking the conduction band offset (CBO) into account, which will substantially help acquisition of the full band structures of the thin films in the CIGS solar-cell device and contribute to the optimal device designs.

• Proceedings of the Optical Society of Korea Conference
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• 2006.02a
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• pp.95-96
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• 2006

• Archives of Plastic Surgery
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• v.34 no.1
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• pp.1-7
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• 2007

Purpose: Human adipose tissue-derived stromal cells(hADSCs) can be expanded in vitro and induced to differentiate into multiple mesenchymal cell types. In this study we have examined various neuronal phenotypes and gene expression profiles of the hADSCs in the neuronal induction. Methods: The hADSCs were isolated from human adipose tissue and they were characterized by the flow cytometry analysis using CD13, CD29, CD34, CD45, CD49d, CD90, CD105 and HLA-DR cell surface markers. We differentiated the hADSCs into the neuronal lineage by using chemical induction medium and observed the cells with contrast microscopy. The immunocytochemistry and western blotting were performed using the NSE, NeuN, Trk-A, Vimentin, N-CAM, S-100 and ${\beta}$-Tubulin III antibodies. Results: The hADSCs were positive for CD13($90.3{\pm}4%$), CD29($98.9{\pm}0.7%$), CD49d($13.6{\pm}6%$), CD90 ($99.4{\pm}0.1%$), CD105($96%{\pm}2.8%$) but negative for CD34, CD45 and HLA-DR. The untreated cultures of hADSCs predominately consisted of spindle shaped cells and a few large, flat cells. Three hours after the addition of induction medium, the hADSCs had changed morphology and adopted neuronal-like phenotypes. The result of immunocytochemistry and western blotting showed that NSE, NeuN, Trk-A, Vimentin, N-CAM, S-100 and ${\beta}$-Tubulin III were expressed. However, NSE, NeuN, Vimentin were weakly expressed in the control. Conclusion: Theses results indicate that hADSCs have the capabillity of differentiating into neuronal lineage in a specialized culture medium. hADSCs may be useful in the treatment of a wide variety of neurological disorders.

• Journal of the Mineralogical Society of Korea
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• v.28 no.2
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• pp.173-185
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• 2015

Janggun mine (longitude $129^{\circ}$ 03'38.91" Latitude $36^{\circ}$ 51'31.59") had been operated as an underground mine for last few decades. As the part of the remediation process, the surface of tailing dump was covered with uncontaminated soil about 20 cm in depth and acacia trees were planted. Heavy metal uptake of acacia from tailing soil has continued for the past 15 years. Heavy metal concentration ranges of tailing soil that contaminated with As (66.43-9325.34 mg/kg), Cd (0.96-1.09 mg/kg), Cu (16.90-57.60 mg/kg), Pb (57.33-945.67 mg/kg), and Zn (154.48-278.61 mg/kg) have higher than those of control soil As (38.98 mg/kg), Cd (0.42 mg/kg), Cu (10.26 mg/kg), Pb (8.21 mg/kg), Zn (46.74 mg/kg). The As, Cd, Cu, Pb and Zn concentrations of leaf of acacia in highly contaminated tailing dump were 165.95, 0.04, 10.68, 3.18, 48.11 mg/kg, respectively. The metal contents of leaf of acacia tree that obtained from uncontaminated control soil are 1.31 of As, 3.90 of Cu, 0.22 of Pb and 11.01 mg/kg of Zn. It was investigated that in the acacia tree, heavy metals such as As, Cu, Pb and Zn tend to be more highly concentrated in bark and leaf, compared with sapwood and heartwood.