• Journal of the Korean GEO-environmental Society
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• v.10 no.6
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• pp.61-68
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• 2009

The main objective of this study was to examine the removal of heavy metals from water by inflated vermiculites. The component of vermiculites was analyzed by XRF, and the concentration of metal ion was measured by ICP-AES. Serial batch kinetic tests and batch sorption tests were conducted to determine the removal characteristics for heavy metals in aqueous solutions. As a result, solution pH values of tests with the inflated vermiculites generally increased and then stabilized. Equilibrium pHs were generally established within 5 hrs. In addition, removal rates of inflated vermiculites were tested at the initial concentration of 3 mg/L. As a result, at equilibrium concentration, except for chromium (36.23%), Most of the heavy metals were effectively removed (96.08~98.54%). Finally, sorption data were correlated with both Langmuir and Freundlich isotherms. The Qmax obtained from Langmuir isotherm were determined to Pb $725.4mg\;kg^{-1}$, Cd $568.8mg\;kg^{-1}$, Zn $540.2mg\;kg^{-1}$, Cu $457.2mg\;kg^{-1}$ Cr $0.9mg\;kg^{-1}$ respectively. The results of the study indicate that inflated vermiculites can be properly used as an adsorbent for various heavy metals because of its outstanding removal rate.

• Economic and Environmental Geology
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• v.42 no.5
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• pp.435-444
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• 2009

In situ stabilization of heavy metals through adsorption onto indigenous bacterial biofilm developed on soil particles was investigated. Biofilms were developed in soil columns by supply of various carbon sources such as acetate, lactate and glucose. During development of biofilms, acetate, lactate, and glucose solutions were flew out from the soil columns with volume ratios of 98.5%, 97.3%, and 94.7%, respectively, when compared with soil column supplied with deionized water. Decrease in effluent amounts through the soil columns amended with carbon sources over time indicated the formation of biofilms resulting in decrease of soil porosity. Solutions of Cd, Cr(VI), Cu, Pb, and Zn were injected into the biofilms supported on soil particles in the columns, and the dissolved heavy metals in effluents were determined. Concentrations of dissolved Cd, Cr(VI), Cu, and Zn in the effluents through biofilm columns were lower than those of control column supplied with deionized water. The result was likely due to enhanced adsorption of the metals onto biofilms. Efficiency of metal removal by biofilms depended on the type of carbon sources supplied. The enhanced removal of dissolved heavy metals by bacterial biofilms in this study may be effectively applied to technical development of in situ stabilization of heavy metals in natural soil formation contaminated with heavy metals.

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.215.3-216
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• 2001

No Abstract, See Full Text

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1001-1004
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• 2008

An advanced backplane circuit technology for AMOLED using amorphous silicon TFTs with commercial level reliability, uniformity and lifetime was recently integrated into a prototype device. Differential aging of T98>100 hrs at 200 cd/m2 brightness and >10,000hrs lifetime is demonstrated. A 2.2" QVGA ($240{\times}320$) prototype has been developed and shown having the above-mentioned high performance.

• Journal of environmental and Sanitary engineering
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• v.3 no.2 s.5
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• pp.91-98
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• 1988

This study was carried out to investigate the Pollution of heavy metals in Soil, collected from the 50 sampling sites in 1986. The results were as follows; 1. In the average contents of Cd, the highest value was 0.33mg/kg in the Industrial area, the lowest value was 0.06 mg/kg in the Greenbelt and 0.10-0.22mg/kg in the other areas. 2. In the average contents of Cu, the highest value was 33.46mg/kg in the Industrial area, the lawest value was 3.79mg/kg in the Greenbelt and 4.69-12.21mg/kg in the other areas. 3. In the average contents of As, the highest value was 1.80mg kg in the Residential area, the lowest value was 0.43mg/kg in the Greenbelt and 0.64-1.65mg/kg in the other areas. 4. In the average contents of Zn, the highest value was 29.84mg/kg in the out wall of Seoul, the lowest value was 17.32mg/kg in the Greenbelt and 19.62-26.71mg/kg in the other areas. 5. In the average contents of Pb, the highest value was 17.09mg/kg in the Industrial area, the lowest value was 5.21mg/kg in the Reclamated waste and 5.67 -14.10mg/kg in the other areas. 6. Distribution of Heavy metals was Zn>Cu>Pb>As>Cd and the relations of Zn-Cd, Pb-Cd, Pb-Cu, Pb-Zn were shown the correlation significantly (P< 0.01).

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1752-1760
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• 2005

In this experiment, the effects of cage density (CD) and probiotic supplementation (PS) on laying performance, metabolic profile, and egg quality in peak-producing hens were evaluated. After blocking according to the cage location, Lohman layers (n = 180, 46 wks of age) were allocated randomly to two levels of CD (540 vs. 360 $cm^2$/hen) and three levels of PS (0, 0.15, and 0.30%). Probiotic contained Enterococcus faecium culture (10${\times}$10$^9$ cfu/g). Egg production (EP) and feed consumption (FC) were measured daily; egg weight (EW) was measured bi-weekly; BW was measured before and after the experiment; and blood samples were obtained at the end of the experiment. The data were analyzed using two-way ANOVA. Increasing CD decreased FC (125.0 vs. 120.8 g/d, p<0.0001) and FCR (1.93 vs. 1.87, p<0.0001) and did not alter EP, EW, and BW. Increasing level of PS linearly decreased FC (p<0.02) and FCR (p<0.006). Averages were 123.9, 123.2, and 121.6 g/d for FC and 1.91, 1.92, and 1.86 for FCR in hens supplemented with 0, 0.15, and 0.30% probiotic, respectively. Hens placed in high-density cages had greater serum corticosterone concentration than hens placed in normal-density cages (12.8 vs. 11.3 $\mu$g/dL, p<0.04); CD did not affect concentrations of other metabolites. Increasing level of PS linearly increased serum glucose, albumin, and creatine concentrations and quadratically increased total protein, globulin, Ca, and P concentrations. Average concentrations (mg/dL) were 260, 297, and 305 for glucose; 6.28, 8.09, and 7.58 for total protein; 1.98, 2.48, and 2.38 for albumin; 4.30, 5.62, and 5.19 for globulin; 0.40, 0.52, and 0.54 for creatine; 16.0, 16.5, and 16.3 for Ca; and 6.27, 8.14, and 7.17 for P in hens supplemented with 0, 0.15, and 0.30% probiotic, respectively. There was no effect of CD on egg quality. Increasing level of PS linearly improved yolk color (YC) and quadratically increased albumen index (AI) and Haugh unit (HU). The mean values were 9.67, 9.75, and 10.58 for YC; 8.94, 6.93, and 8.72% for AI; and 85.6, 74.9, and 82.9 for HU for hens supplemented with 0, 0.15, and 0.30% probiotic, respectively. There was also CD by PS effect on FC, EP, and serum glucose, total protein, albumin, globulin, creatine, Ca and P concentrations. In conclusion, increased CD partially depressed laying performance and caused stress. Probiotic supplementation improved laying performance and metabolic profile. It also partially alleviated the adverse effects of stress resulting from increased caging density.

• Journal of Korean Society of Forest Science
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• v.81 no.2
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• pp.117-123
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• 1992

In this study, the water soluble sulfur, lead and cadmium contents of Prunus yedoerais leaves were analysed. The water soluble sulfur content considered as a main pollution indicator was extracted by the conventional barium sulfate method and the concentrations were calculated. The results obtained are as follows ; 1. The water soluble sulfur contents of the leaves collected from the heavy traffic roadside trees were two time higher than that of control materials on average. It was presumed those trees has been under meaningful pollutants impact. The water soluble sulfur contents of leaves between Cheonju and Iri was higher than that between Iri and Kunsan. 2. The range of Pb contents from roadside trees was 11.9-34.5 ppm for exceeding the control. The trees grown on the right roadside were more heavliy Pb-contaminated. 3. The range of Cd contents from roadside trees grown between Iri and Kunsan, the site-to-site variations of Cd concentration was not significant.

• Toxicological Research
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• v.28 no.2
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• pp.93-98
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• 2012

This study has attempted to establish an analysis method through validation against heavy metals in the body (Pb, Cd and Hg) using ICP-MS and Gold amalgamation and find out the relevance between heavy metal and Alzheimer's disease after analyzing the distribution of heavy metal concentration (Pb, Cd and Hg) and correlations between a control group and Alzheimer's disease group. In this study, Pb and Cd levels in the blood and serum were validation using ICP-MS. For analysis of Hg levels in the blood and serum, the gold amalgamation-based 'Direct Mercury Analyzer' has been used. According to an analysis on the heavy metal concentration (Pb, Cd and Hg concentration) in the blood, Cd concentration was high in the Alzheimer's disease group. In the serum, on the contrary, Pb and Hg were high in the Alzheimer's disease group. For analysis of correlations between heavy metal levels in the blood and serum and Alzheimer's disease, t-test has been performed. Even though correlations were observed between the blood lead levels and Alzheimer's disease, they were statistically insignificant because the concentration was higher in a control group. No significance was found in Cd and Hg. In the serum, on the other hand, no statistical significance was found between the heavy metal (Pb, Cd and Hg) and Alzheimer's disease. In this study, no statistical significance was observed between heavy metal and decrease in cognitive intelligence. However, it appears that a further study needs to be performed because the results of the conventional studies were inconsistent.

• Korean Journal of Environmental Agriculture
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• v.34 no.4
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• pp.303-308
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• 2015

BACKGROUND: Recently, various rice by milling degree is sold for health and taste. To provide safe food to consumers, it is need to know the change of heavy metal contents according to milling degree of rice.METHODS AND RESULTS: This study was to investigate residual the levels of cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) as stated in the milling degree of the rice contaminated Cd and Pb from 2011 to 2012 in Chungcheongnam-do. Rice samples exceeded the maximum residue limits (MRL) of Cd and Pb were milled by five degrees (0.0, 2.45, 8.02, 10.48, 15.09%). Milled rice was digested by microwave method, and analyzed heavy metal contents using ICP-OES. Recovery ratios of 4 heavy metals such as Cd, Pb, Cu and Zn were ranged for 79.7-98.9%, and limits of detection (LOD) and limits of quantitation (LOQ) were fulfilled with the normal analytical standards. Concentrations of Cd, Pb, Cu and Zn were ranged 0.416-0.433 mg/kg, 0.183-0.26 mg/kg, 3.639- 3.882 mg/kg and 16.868-19.801 mg/kg, respectively.CONCLUSION: From these results, conforming with increase of milling degree of rice, Cd, Pb, Cu, and Zn contents tended to decrease. The contents of heavy metals were decreased 3.1% in Cd, 29.3% in Pb, 6.4% in Cu and 15.1% in Zn, in according to the highest milling degree of 15.09%.

• Journal of the Korean institute of surface engineering
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• v.49 no.3
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• pp.316-321
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• 2016

To study emission characteristics for dual-emission tandem organic light emitting display (OLED), we fabricated blue fluorescent OLED according to thickness variation of $MoO_x$ as charge generation layer and Al as cathode. The bottom emission characteristics of OLED with $MoO_x$ 2, 3, 5 nm thickness showed threshold voltage of 9, 7, 9 V, maximum current emission efficiency of 19.32, 23.18, 15.44 cd/A and luminance of $1,000cd/m^2$ at applied voltage of 17.6, 13.2, 16.5 V, respectively. The top emission characteristics of OLED with $MoO_x$ 2, 3, 5 nm thickness indicated threshold voltage of 13, 10, 13 V, maximum current emission efficiency of 0.17, 0.23, 0.16 cd/A and luminance of $50cd/m^2$ at applied voltage of 22.6, 16.5, 20.1 V, respectively. In case of thicker or thinner than $MoO_x$ of 3 nm, the emission characteristics were decreased because of mismatching of electron and hole in emission layer. The bottom emission characteristics of OLED with Al 15, 20, 25 nm thickness showed threshold voltage of 8, 8, 7 V, maximum current emission efficiency of 18.42, 22.98, 23.18 cd/A and luminance of $1000cd/m^2$ at applied voltage of 16.2, 13.9, 13.2 V, respectively. The reduction of threshold voltage and increase of maximum current emission efficiency are caused by the increase of current injection according to increase of Al cathode thickness. The top emission characteristics of OLED with Al 15, 20, 25 nm thickness indicated threshold voltage of 7, 7, 8 V, maximum emission luminance of 371, 211, $170cd/m^2$, respectively. The top emission OLED of Al cathode with 15 nm thickness showed maximum luminance and it decreased at thickness of 20 nm. These phenomena are caused by the decrease of intensity of emitted light by reduction of optical transmittance according to increase of Al cathode thickness.